Lifetime control in silicon devices by voids induced by He ion implantation
碳化硅同质外延质量影响因素的分析与综述
第53卷第2期2024年2月人㊀工㊀晶㊀体㊀学㊀报JOURNAL OF SYNTHETIC CRYSTALSVol.53㊀No.2February,2024碳化硅同质外延质量影响因素的分析与综述郭㊀钰1,2,刘春俊1,张新河2,沈鹏远1,张㊀博1,娄艳芳1,彭同华1,杨㊀建1(1.北京天科合达半导体股份有限公司,北京㊀102600;2.深圳市重投天科半导体有限公司,深圳㊀518108)摘要:碳化硅(SiC)外延质量会直接影响器件的性能和使用寿命,在SiC器件应用中起到关键作用㊂SiC外延质量一方面受衬底质量的影响,例如衬底的堆垛层错(SF)会贯穿到外延层中形成条状层错(BSF),螺位错(TSD)会贯穿到外延层中形成坑点或Frank型层错(Frank SF)等㊂另一方面受到外延工艺的影响,如在外延过程中衬底的基平面位错(BPD)受应力等条件作用会滑移形成Σ形基平面位错(Σ-BPD),衬底的TSD或刃位错(TED)会衍生为腐蚀坑(Pits),以及新产生SF和硅滴等㊂因此,获得高质量的SiC外延晶片需要从优选SiC衬底和优化外延工艺两方面入手㊂本文对外延生长过程中晶体缺陷如何转化并影响器件性能进行了系统分析和综述,并基于北京天科合达半导体股份有限公司量产的高质量6英寸SiC衬底,探讨了常见缺陷,如BPD㊁层错㊁硅滴和Pits等的形成机理及其控制技术,并对Σ-BPD的产生机理和消除方法进行研究,最终获得了片内厚度和浓度均匀性良好㊁缺陷密度低的外延产品,完成了650和1200V外延片产品的开发和产业化工作㊂关键词:碳化硅;同质外延;外延生长;缺陷;位错;小坑中图分类号:O78;O484;O47㊀㊀文献标志码:A㊀㊀文章编号:1000-985X(2024)02-0210-08 Analysis and Review of Influencing Factors of SiCHomo-Epitaxial Wafers QualityGUO Yu1,2,LIU Chunjun1,ZHANG Xinhe2,SHEN Pengyuan1,ZHANG Bo1,LOU Yanfang1,PENG Tonghua1,YANG Jian1(1.Beijing TankeBlue Semiconductor Co.,Ltd.,Beijing102600,China;2.Shenzhen MITK Semiconductor Co.,Ltd.,Shenzhen518108,China)Abstract:The performance and lifetime of silicon carbide(SiC)devices are directly affected by the quality of SiC epitaxial films.On the one hand,the quality of SiC epitaxial films is affected by the quality of substrates.For examples,the stacking faults(SF)in substrates penetrate into the epitaxial layer,forming bar-shaped stacking faults(BSF),and the threading screw dislocation(TSD)penetrate into the epitaxial layer to form pits or Frank-type stacking faults(Frank SF).On the other hand, the quality of SiC epitaxial films is also influenced by the epitaxial growing process.For examples,basal plane dislocation (BPD)in the substrate formΣ-basal plane dislocation(Σ-BPD)in the epitaxial layer under thermal stress or other unstable conditions,the TSD and threading edge dislocation(TED)in the substrate may be etched and derived into pits,and SF and silicon droplets may also be produced.Therefore,high quality SiC substrates and optimized epitaxial growing process are both crucial for obtaining high-quality silicon carbide epitaxial wafers.In this article,based on the SiC epitaxial films grown on 6inch SiC substrates batch-produced by TankeBlue Company,the defects reproducing process in substrates during epitaxial growing were analyzed,and the formation mechanism and controlling technology of common defects such as BPD,SF,silicon droplets and pits were overviewed.The generation mechanism ofΣ-BPD and its eliminating methods were also explored. Finally,we obtained the mass-production technologies of SiC epitaxial films with good thickness and concentration uniformity, and low defect density,which are qualified for making650and1200V SiC-based MOSFETs.Key words:SiC;homo-epitaxial;epitaxial growth;defect;dislocation;pit㊀㊀收稿日期:2023-05-29㊀㊀基金项目:北京市科协卓越工程师培养计划㊀㊀作者简介:郭㊀钰(1983 ),女,辽宁省人,博士,教授级高工㊂E-mail:guoyu03201@㊀㊀通信作者:刘春俊,博士,研究员㊂E-mail:liuchunjun@㊀第2期郭㊀钰等:碳化硅同质外延质量影响因素的分析与综述211㊀0㊀引㊀㊀言SiC作为目前被广泛关注的第三代半导体材料,具有高击穿电压㊁高电子迁移率㊁高热导率等特性,由其制备的半导体器件相比传统的硅(Si)基半导体器件拥有体积小㊁开关损耗低㊁功率密度更高等优势㊂随着绿色能源革命对电力电子器件耐高压㊁低功耗需求的日益迫切,以及电动汽车㊁充电桩等新兴应用的蓬勃发展, SiC器件在智能电网㊁电动汽车㊁轨道交通㊁新能源并网㊁开关电源㊁工业电机和白色家电等领域展现出良好的发展前景和巨大的市场潜力㊂与传统硅功率器件制作工艺不同,SiC功率器件不能直接制作在SiC单晶材料上,必须在导通型SiC单晶衬底上使用外延技术生长出高质量的外延材料,然后在外延层上制作各类器件㊂之所以不直接在SiC衬底上制作SiC器件,一方面是由于衬底的杂质含量较高,且电学性能不够好㊂另一方面是掺杂难度大,即使采用离子注入的方式,也需要后续的高温退火,远不如在外延层上的掺杂效果好㊂因此,制造出外延层的掺杂浓度和厚度符合设计要求的SiC器件至关重要㊂常见的SiC外延技术有化学气相沉积(chemical vapor deposition,CVD)㊁液相外延生长(liquid phase epitaxy,LPE)㊁分子束外延生长(molecular beam epitaxy,MBE)等,目前CVD是主流技术,具备较高生长速率㊁能够实现可控掺杂调控等优点㊂CVD外延生长通常使用硅烷和碳氢化合物作为反应气体,氢气作为载气,氯化氢作为辅助气体,或使用三氯氢硅(TCS)作为硅源代替硅烷和氯化氢,在约1600ħ的温度条件下,反应气体分解并在SiC衬底表面外延生长SiC薄膜㊂目前国内外SiC外延技术已经取得较大进展,产业界也已成功实现6英寸(1英寸=2.54cm)SiC外延批量生产㊂国外产业化公司主要有美国Wolfspeed公司㊁II-VI公司,日本的Showa Ddenko公司等,国内有厦门瀚天天成电子科技有限公司㊁东莞天域半导体有限公司㊁河北普兴电子科技股份有限公司㊁三安集成等㊂2022年美国Wolfspeed公司已成功实现8英寸SiC外延产品的量产㊂市场上主流的量产产品主要是650㊁1200㊁1700V金氧半场效晶体管(metal-oxide-semiconductor field-effect transistor,MOSFET)器件用6英寸外延产品㊂本研究团队基于十多年在SiC衬底材料制备技术研究和产业推广经验的积累,2022年开始启动SiC外延技术研发,重点针对1200V车规级MOSFET器件用SiC外延材料进行研发和产业化工作㊂本文首先介绍了SiC外延的研究历史,然后结合本团队SiC外延产品相关研发工作综述了SiC外延掺杂浓度控制和缺陷控制方面的研究进展,最后对国产SiC外延的发展进行了总结和展望㊂1㊀研发历史SiC同质外延技术研究需要基于SiC衬底开展,因此研发时间晚于SiC衬底,最早开始于20世纪60年代㊂研究人员主要采用了液相外延法[1-3]和CVD法进行SiC同质外延[4-9]㊂但由于SiC存在200多种晶体结构,外延生长时存在严重的多型夹杂问题,因此早期获得的外延材料质量都很差,这也制约了SiC器件的发展㊂第一个突破性的里程碑是在1987年,Kuroda等[10]和美国Kong等[11]各自相继提出了台阶流外延生长模型,在6H-SiC衬底上进行完美多型体复制,并给出了最优偏离晶向和偏角㊂具体来说,代表SiC晶型的堆垛顺序信息主要在SiC衬底表面台阶的侧向,通过SiC衬底表面偏角度的控制,使得同质外延在衬底表面原子台阶处侧向生长,从而继承衬底的堆垛次序,通过台阶流生长实现晶型的完美复制㊂这项技术同样适用其他晶型,如4H-SiC㊁15R-SiC的同质外延生长㊂4H-SiC同质外延的成功促进了SiC基肖特基二极管的研发,带动了4H-SiC在功率器件应用领域独特的发展㊂第二个标志性里程碑是热壁(温壁)CVD反应室设计,传统冷壁CVD反应腔室[12-13]结构较为简单,但存在一些缺点,如晶片表面法线方向的温度梯度非常大,导致SiC晶片翘曲比较严重[14];另外冷壁CVD加热效率比较低,热辐射损耗严重㊂通过热壁CVD反应室设计,腔室内温度梯度得到显著降低,容易实现良好的温度均匀性,这对于产业化生产至关重要㊂第三个里程碑是氯基快速外延生长技术,传统SiC的CVD生长技术通常使用硅烷和碳氢化合物作为反应气体,氢气作为载气,气相中Si团簇容易形成Si滴,导致外延生长工艺窗口相对较窄,同时也限制了外延生长的速率㊂通过引入氯基化学成分(通常有TCS,或者HCl)可以极大地抑制Si团簇,目前已成功应用于212㊀综合评述人工晶体学报㊀㊀㊀㊀㊀㊀第53卷SiC 快速外延生长中[15]㊂近年来,SiC 外延技术逐渐成熟,产业研究重点关注外延材料掺杂浓度控制和缺陷控制两个方面㊂2㊀SiC 外延层的掺杂浓度控制SiC 是优秀的宽禁带半导体材料,其优点是可以相对容易地在一个宽的范围内控制n 型和p 型掺杂㊂氮(N)或磷(P)用于n 型掺杂,而铝(Al)常用于p 型掺杂㊂硼(B)也曾用作p 型掺杂,但其电离能较大(约350MeV)[16],现在已经不是p 型掺杂的首选㊂Larkin 等[17-19]发现的竞位效应是实现SiC 掺杂控制的关键㊂N 原子替位C 原子位置,而P㊁Al 和B 替位Si 原子位置㊂因此,低C /Si 比有利于提高N 掺杂效率,高C /Si 比不利于N 的掺入;对于Al 和B 则刚好相反㊂目前大部分SiC 器件是基于n 型外延材料制作,氮气也是普遍采用的掺杂气体,N 掺杂与氮气流量㊁生长温度和压力㊁C /Si 比㊁生长速率等参数的依赖关系已有详细的研究[20-22],可以实现N 掺杂浓度大范围的调控(1ˑ1014~2ˑ1019cm -3)㊂对于大尺寸SiC 外延材料,SiC 外延层掺杂浓度的均匀性(δ/mean)是研究及产业界目前关注的另一重点㊂2011年Burk 等采用热壁气相外延(vapour phase epitaxy,VPE)炉制作出了厚度均匀性和浓度均匀性分别低于1.6%和12%的6英寸SiC 外延片[23],2014年Thomas 等在2800W 设备上获得了厚度和浓度均匀性分别低于1.5%和8%㊁良品率97.5%的外延片[24-25]㊂8英寸外延片方面,Mattia 和Danilo 等各自在PE1O8设备上获得厚度和浓度均匀性均低于2%的外延片[26]㊂在水平式外延生长中,气体高速流入生长腔室,中心流速高,两侧接近生长腔室边界的地方流速降低;同时在气体流动的方向上,随着反应气体的消耗,反应气体的浓度降低,这些现象会引起SiC 外延层厚度和浓度的不均匀,进而影响器件的性能㊂解决上述问题的方法是设计适当的反应腔室结构,从进气端到尾气端的反应腔室逐步变窄,使得气体的速度沿着流动方向增加,同时反应气体向衬底的扩散距离减小,抵消气体消耗和边界流速降低带来的影响㊂另外,通过调整SiC 衬底的旋转速度,使用适当比例的氩气和氢气的混合气体作为旋转气体源,调整反应气体中的C /Si 比例,调整中路和旁路的反应气体和掺杂气体的流量,都可以获得更加均匀的载流子浓度和厚度分布[27]㊂图1㊀量产外延片的载流子浓度均匀性(a)和厚度均匀性(b)分布统计Fig.1㊀Uniformity of doping (a)and thickness (b)of epi-wafers 本团队采用水平式外延生长方法,三氯氢硅和乙烯作为反应气源,氮气作为掺杂气体,氢气作为载气,氢气和氩气作为驱动托盘旋转的气源,生长厚度适用于1200V 的SiC 基MOSFET 用SiC 外延层㊂通过调整掺杂氮气在中心和边缘分布比例㊁托盘旋转的速度以及旋转气体中氩气与氢气的比例,优化外延工艺的C /Si 比等生长参数,实现SiC 外延层掺杂浓度及均匀性的有效控制,图1是量产1000片的厚度和浓度均匀性统计数据,C /Si 比在1.0~1.2㊁温度在1600~1650ħ和压力在100mbar 的工艺条件下,统计的外延产品100%达到厚度均匀性小于3%㊁浓度均匀性小于6%㊂3㊀SiC 外延层的缺陷控制研究根据晶体缺陷理论,SiC 外延材料的主要缺陷可归纳为4大类:点缺陷㊁位错(属于线缺陷)㊁层错(属于面缺陷)和表面缺陷(属于体缺陷)㊂3.1㊀点缺陷SiC 外延材料的点缺陷主要有硅空位㊁碳空位㊁硅碳双空位等缺陷[28-30],它们在禁带中产生深能级中心,影响材料的载流子寿命㊂在轻掺杂的SiC 外延层中,点缺陷产生的深能级中心浓度通常在5ˑ1012~2ˑ1013cm -3,与外延生长条件特别是C /Si 比和生长温度相关㊂3.2㊀位㊀错SiC 材料的位错包括螺位错(threading screw dislocation,TSD)㊁刃位错(threading edge dislocation,TED)㊀第2期郭㊀钰等:碳化硅同质外延质量影响因素的分析与综述213㊀和基平面位错(basal plane dislocation,BPD)㊂微管是伯氏矢量较大的螺位错形成的中空管道,可认为是一种超螺位错㊂SiC外延层的位错缺陷基本都和衬底相关,图2是SiC外延层中观察到的典型位错演变图[31-32]㊂大部分微管和螺位错会复制到外延层中,在合适的工艺条件下,部分微管分解为单独的螺位错,形成微管闭合[33],只有一小部分TSD(<2%)转为Frank型层错[34-35]㊂衬底TED基本都会复制到外延层中㊂图2㊀4H-SiC外延层中位错演变图Fig.2㊀Schematic illustration of dislocation evolution process in4H-SiC epitaxial layerBPD位错主要源于衬底中BPD向外延层的贯穿,通常偏4ʎ4H-SiC衬底中大部分BPD位错(>99%)在外延过程中会转化为TED位错,只有少于1%左右的BPD会贯穿到外延层中并达到外延层表面㊂在后续器件制造中,BPD主要影响双极型器件的稳定性,如出现双极型退化现象[36-40]㊂在正向导通电流的作用下, BPD可能会延伸至外延层演变成堆垒层错(SF),造成器件正向导通电压漂移㊂由于刃位错对器件性能的影响要小得多,所以提高SiC外延生长过程中BPD转化为TED的比例,阻止衬底中的BPD向外延层中延伸对提高器件的性能十分重要㊂对于BPD向TED的转化技术已经有比较多的研究报道,例如,外延生长前的KOH刻蚀或氢气刻蚀优化表面[41]㊁外延生长间断[42],或者提高生长速率,结合这些技术,转化率已经提升到99.8%,甚至达到100%[43]㊂此外生长过程中,在应力等条件作用下,BPD很容易在衬底和外延层界面上沿着台阶流法线方向发生滑移,形成界面位错(interfacial dislocations)[44-45],滑移方向取决于BPD的伯氏矢量及应力方向㊂特定条件下,成对BPD同时发生滑移,会形成Σ-BPD㊂在本团队研发过程中也观察到过该缺陷,其典型形貌如图3所示,光致发光检测BPD形貌如图3(a)所示,对外延片进行KOH腐蚀后形貌如图3(b)所示,可以看到一个Σ-BPD包含两条界面位错,其长度可以达到毫米级,在其尾部存在两个BPD㊂Σ-BPD形成机理示意图如图3(c)所示[46-47],其起源于衬底的BPD对,其伯氏矢量方向刚好相反,滑移过程中形成两条界面位错和2个半环位错(half-loop arrays,HLAs)㊂半环位错的长度不一,决定于其驱动力大小,影响滑移的驱动力主要是温场的不均匀性㊂图3㊀Σ-BPD的形貌图(a)㊁氢氧化钾腐蚀坑图(b)和形成机理示意图(c)Fig.3㊀Morphology(a),etched image by KOH(b)and schematic illustration of formation mechanism(c)ofΣ-BPD针对外延BPD,本文在快速外延生长的基础上优化外延层缓冲层工艺窗口,目前可以实现BPD密度小于0.1cm-3的外延层批量制备,如图4所示㊂3.3㊀层错缺陷SiC外延层中的层错包括两大类:一类来源于衬底的层错和位错缺陷,衬底的层错会导致外延层形成214㊀综合评述人工晶体学报㊀㊀㊀㊀㊀㊀第53卷图4㊀外延片的BPD 分布(a)及其统计(b)Fig.4㊀Distribution of BPD (a)and its statistics (b)of epi-wafers Bar-shaped SFs [48-49],衬底的部分TSD 如3.2所述会形成Frank SFs;另一类层错为生长层错(in-grown SFs),是外延生长过程中产生的,与衬底质量没有关系㊂目前,大多数外延层错属于第二类,这些层错中绝大部分为Shockley SFs,是通过在基平面中的滑移产生的[50-51]㊂这些层错缺陷都会对器件性能产生不利影响,例如漏电流的增加㊂降低外延生长速率㊁原位氢气刻蚀优化㊁增加生长温度㊁改善衬底质量都可以有效降低层错数量,本研究团队已经可以提供Shockley SFs 密度小于0.15cm -2的6英寸SiC 衬底㊂3.4㊀表面缺陷SiC 外延层表面缺陷尺度比较大,一般通过光学显微镜可以直接观察到,包括掉落物[52]㊁三角形缺陷[53-54]㊁ 胡萝卜 缺陷[55-56]㊁彗星缺陷[57]㊁硅滴[58]和浅坑[59-60]㊂掉落物主要由反应室的部件上形成的SiC 颗粒脱落形成,通过定期清理或更换反应室部件能够有效控制㊂其他几种表面缺陷的形成机制目前已经有了较多研究,虽然不能形成统一的模型,但是大部分与衬底表面状态(包括划痕/损伤层㊁颗粒沾污㊁凹坑)㊁衬底位错(特别是TSD)等缺陷存在一定的关联性㊂由于台阶流生长模式的放大作用和位错转化的综合效应,导致缺陷形成各种宏观表面形貌特征㊂表面缺陷与器件性能的影响目前也已经有了较多的研究报道,除浅坑缺陷外,其他表面缺陷基本都会对器件的性能产生一定的不利影响,导致器件击穿电压降低或者反向漏流增加[61]㊂浅坑(Pits)是4H-SiC 外延层表面出现在TSD 位错顶端的小凹陷或小坑状的形貌缺陷,其宽度尺度小于10μm㊂TED 在外延层表面引起的小坑尺寸远小于TSD 诱发的小坑尺寸,很难被观察到㊂图5是本团队在外延生长中观察到的典型浅坑AFM 形貌,在台阶流动方向的上游端,小坑缺陷有陡峭的倾斜侧面,在下游端,侧面相对平缓,通过AFM 可以看到Pits 宽度为2μm,深度为4nm,深宽比约为0.002㊂Ohtani㊁Noboru 等则利用TUNA 技术研究了Pits 和Large Pits 的产生机理,认为宽度在几微米㊁深度在14nm 左右的Large pits 是由TSD 产生,而宽度在1μm㊁深度在3~4nm 的Pits 由TED 产生[62-63]㊂近年来,有研究表明:当存在浅坑时,由于几何效应会导致局部电场集中,对于二极管特性基本不存在负面影响㊂Kudou 等[64]研究了Pits 缺陷对SiC 器件的影响,认为Pits 密度不会影响SBD 的漏电流和MOSFET 的TDDB 栅氧可靠性㊂同时指出深宽比较小(小于0.02)的Pits对SBD 和MOSFET 的影响较小㊂图5㊀外延表面宽度和深度分别为2μm 和4nm 的浅坑的AFM 照片Fig.5㊀AFM image of a pit with 2μm width and 4nm depth降低Pits 的主要途径包括:优选TSD 数量较少的优质衬底㊁降低碳硅比和降低外延生长速率㊂目前市场上主要的商业化衬底中TSD 的密度小于1000cm -2㊂本研究团队已经可以提供TSD 密度小于300cm -2的6英寸SiC 衬底㊂通过采用优质衬底,调整外延工艺,可以将Pits 数量从103降低到50以内㊂综合来看,SiC 外延层缺陷一方面取决于衬底结晶质量以及表面加工质量,另一方面受制于外延生长工艺窗口的优化,需要综合考虑各种缺陷的调整方案,例如提高外延生长速率会导致BPD 向TED 转化率的提㊀第2期郭㊀钰等:碳化硅同质外延质量影响因素的分析与综述215㊀高,但会导致层错密度的增加㊂基于本研究团队量产的高质量6英寸SiC衬底,本团队通过大量的实验研究,可以有效控制住SiC外延的各种缺陷,完成650和1200V外延片产品开发和产业化工作㊂图6是典型的650和1200V外延片产品缺陷mapping图,3mmˑ3mm良品率分别为98.9%和97.3%㊂图6㊀650和1200V外延片产品缺陷mapping图Fig.6㊀Mapping diagram of defects in650and1200V epi-wafers4㊀结语与展望SiC外延在产业链中起着承上启下的重要作用,通过不断积累对SiC材料的性能认知和改良,以及器件的不断迭代验证,最终提升外延品质,推动SiC器件的应用㊂本文采用天科合达自有的商业化6英寸衬底,在4H-SiC同质外延过程中,研究了外延层中BPD㊁层错㊁硅滴和Pits缺陷的控制,并对Σ-BPD的产生机理和消除进行研究,最终获得厚度均匀性小于3%㊁浓度均匀性小于6%㊁表面粗糙度小于0.2nm㊁良品率大于96%㊁BPD密度小于0.1cm-2的外延产品㊂目前从本团队的研发进度来看,通过对工艺温度㊁C/Si比和生长速率等参数优化使得浓度和厚度均匀性分别控制在3%和2%以内,BPD的密度可以控制在0.075cm-2以内,但仍需要大量的外延数据进行工艺稳定性验证㊂参考文献[1]㊀BRANDER R W,SUTTON R P.Solution grown SiC p-n junctions[J].Journal of Physics D:Applied Physics,1969,2(3):309-318.[2]㊀IKEDA M,HAYAKAWA T,YAMAGIWA S,et al.Fabrication of6H-SiC light-emitting diodes by a rotation dipping technique:electroluminescence mechanisms[J].Journal of Applied Physics,1979,50(12):8215-8225.[3]㊀ZIEGLER G,LANIG P,THEIS D,et al.Single crystal growth of SiC substrate material for blue light emitting diodes[J].IEEE Transactions onElectron Devices,1983,30(4):277-281.[4]㊀MATSUNAMI H,NISHINO S,ONO H.IVA-8heteroepitaxial growth of cubic silicon carbide on foreign substrates[J].IEEE Transactions onElectron Devices,1981,28(10):1235-1236.[5]㊀JENNINGS V J,SOMMER A,CHANG H C.The epitaxial growth of silicon carbide[J].Journal of the Electrochemical Society,1966,113(7):728.[6]㊀CAMPBELL R B,CHU T L.Epitaxial growth of silicon carbide by the thermal reduction technique[J].Journal of the Electrochemical Society,1966,113(8):825.[7]㊀MUENCH W V,PFAFFENEDER I.Epitaxial deposition of silicon carbide from silicon tetrachloride and hexane[J].Thin Solid Films,1976,31(1/2):39-51.[8]㊀YOSHIDA S,SAKUMA E,OKUMURA H,et al.Heteroepitaxial growth of SiC polytypes[J].Journal of Applied Physics,1987,62(1):303-305.[9]㊀NISHINO S,POWELL J A,WILL H A.Production of large-area single-crystal wafers of cubic SiC for semiconductor devices[J].AppliedPhysics Letters,1983,42(5):460-462.[10]㊀KURODA N,SHIBAHARA K,YOO W,et al.Step-controlled VPE growth of SiC single crystals at low temperatures[C]//Extended Abstracts ofthe1987Conference on Solid State Devices and Materials.August25-27,1987.Nippon Toshi Center,Tokyo,Japan.The Japan Society of Applied Physics,1987:032156.[11]㊀KONG H,KIM H J,EDMOND J A,et al.Growth,doping,device development and characterization of CVD beta-SiC epilayers on Si(100)andalpha-SiC(0001)[J].MRS Proceedings,1987,97:233.216㊀综合评述人工晶体学报㊀㊀㊀㊀㊀㊀第53卷[12]㊀JR A B A,ROWLAND L B.Homoepitaxial vpe growth of SiC active layers[J].Physica Status Solidi(b),1997,202(1):263-279.[13]㊀RUPP R,MAKAROV N Y,BEHNER H,et al.Silicon carbide epitaxy in a vertical CVD reactor:experimental results and numerical processsimulation[J].Physica Status Solidi(b),1997,202(1):281-304.[14]㊀KIMOTO T,ITOH A,MATSUNAMI H.Step-controlled epitaxial growth of high-quality SiC layers[J].Physica Status Solidi(b),1997,202(2):247-262.[15]㊀THOMAS B,BARTSCH W,STEIN R A,et al.Properties and suitability of4H-SiC epitaxial layers grown at different CVD systems for highvoltage applications[J].Materials Science Forum,2004,493(457-460):181-184.[16]㊀LA VIA F,CAMARDA M,CANINO A,et al.Fast growth rate epitaxy by chloride precursors[J].Materials Science Forum,2013,740/741/742:167-172.[17]㊀LARKIN D J,SRIDHARA S G,DEVATY R P,et al.Hydrogen incorporation in boron-doped6H-SiC CVD epilayers produced using site-competition epitaxy[J].Journal of Electronic Materials,1995,24(4):289-294.[18]㊀LARKIN D J,NEUDECK P G,POWELL J A,et al.Site-competition epitaxy for superior silicon carbide electronics[J].Applied PhysicsLetters,1994,65(13):1659-1661.[19]㊀LARKIN D J.SiC dopant incorporation control using site-competition CVD[J].Physica Status Solidi(b),1997,202(1):305-320.[20]㊀WANG R J,BHAT I B,CHOW T P.Epitaxial growth of n-type SiC using phosphine and nitrogen as the precursors[J].Journal of AppliedPhysics,2002,92(12):7587-7592.[21]㊀KIMOTO T,NAKAZAWA S,HASHIMOTO K,et al.Reduction of doping and trap concentrations in4H-SiC epitaxial layers grown by chemicalvapor deposition[J].Applied Physics Letters,2001,79(17):2761-2763.[22]㊀TSUCHIDA H,KAMATA I,JIKIMOTO T,et al.Epitaxial growth of thick4H-SiC layers in a vertical radiant-heating reactor[J].Journal ofCrystal Growth,2002,237/238/239:1206-1212.[23]㊀BURK A A,TSVETKOV D,BARNHARDT D,et al.SiC epitaxial layer growth in a6ˑ150mm warm-wall planetary reactor[J].MaterialsScience Forum,2012,717/718/719/720:75-80.[24]㊀KOJIMA K,SUZUKI T,KURODA S,et al.Epitaxial growth of high-quality4H-SiC carbon-face by low-pressure hot-wall chemical vapordeposition[J].Japanese Journal of Applied Physics,2003,42(Part2,No.6B):L637-L639.[25]㊀THOMAS B,ZHANG J E,MOEGGENBORG K,et al.Progress of SiC epitaxy on150mm substrates[J].Materials Science Forum,2015,821/822/823:161-164.[26]㊀MATTIA M,EGIDIO C,DANILO C,et al.Development of n-type epitaxial growth on200mm4H-SiC wafers for the next generation of powerdevices[J].Microelectronic Engineering,2023,274(1):111976.[27]㊀THOMAS B,ZHANG J E,CHUNG G Y,et al.Homoepitaxial chemical vapor deposition of up to150μm thick4H-SiC epilayers in a10ˑ100mmbatch reactor[J].Materials Science Forum,2016,858:129-132.[28]㊀KENNETH G I.Growth of very uniform silicon carbide epitaxial layers,US6063186A[P].1999-06-24.[29]㊀AYEDH H M,HALLÉN A,SVENSSON B G.Elimination of carbon vacancies in4H-SiC epi-layers by near-surface ion implantation:influenceof the ion species[J].Journal of Applied Physics,2015,118(17):175701.[30]㊀AYEDH H M,KVAMSDAL K E,BOBAL V,et al.Carbon vacancy control in p+-n silicon carbide diodes for high voltage bipolar applications[J].Journal of Physics D:Applied Physics,2021,54(45):455106.[31]㊀MIYAZAWA T,TSUCHIDA H.Point defect reduction and carrier lifetime improvement of Si-and C-face4H-SiC epilayers[J].Journal ofApplied Physics,2013,113(8):083714.[32]㊀RANA T,CHUNG G,SOUKHOJAK A,et al.Interfacial dislocation reduction by optimizing process condition in SiC epitaxy[J].MaterialsScience Forum,2022,63(9):99-103.[33]㊀ZHANG X A,NAGANO M,TSUCHIDA H.Basal plane dislocations in4H-SiC epilayers with different dopings[J].Materials Science Forum,2012,725:27-30.[34]㊀KAMATA I,TSUCHIDA H,JIKIMOTO T,et al.Structural transformation of screw dislocations via thick4H-SiC epitaxial growth[J].JapaneseJournal of Applied Physics,2000,39(12R):6496.[35]㊀DANIELSSONÖ,FORSBERG U,JANZÉN E.Predicted nitrogen doping concentrations in silicon carbide epitaxial layers grown by hot-wallchemical vapor deposition[J].Journal of Crystal Growth,2003,250(3/4):471-478.[36]㊀TSVETKOV V F,ALLEN S T,KONG H S,et al.Recent progress in SiC crystal growth[C]//International Conference on Silicon Carbide andRelated Materials,1995,142:317.[37]㊀LENDENMANN H,DAHLQUIST F,JOHANSSON N,et al.Long term operation of4.5kV PiN and2.5kV JBS diodes[J].Materials ScienceForum,2001,353/354/355/356:727-730.[38]㊀BERGMAN P,LENDENMANN H,NILSSON PÅ,et al.Crystal defects as source of anomalous forward voltage increase of4H-SiC diodes[J].Materials Science Forum,2001,353/354/355/356:299-302.[39]㊀LENDENMANN H,BERGMAN P,DAHLQUIST F,et al.Degradation in SiC bipolar devices:sources and consequences of electrically active㊀第2期郭㊀钰等:碳化硅同质外延质量影响因素的分析与综述217㊀dislocations in SiC[J].Materials Science Forum,2003,433/434/435/436:901-906.[40]㊀MUZYKOV P G,KENNEDY R M,ZHANG Q,et al.Physical phenomena affecting performance and reliability of4H-SiC bipolar junctiontransistors[J].Microelectronics Reliability,2009,49(1):32-37.[41]㊀SKOWRONSKI M,HA S.Degradation of hexagonal silicon-carbide-based bipolar devices[J].Journal of Applied Physics,2006,99(1):011101.[42]㊀YANG L,ZHAO L X,WU H W,et al.Characterization and reduction of defects in4H-SiC substrate and homo-epitaxial wafer[J].MaterialsScience Forum,2020,1004:387-392.[43]㊀STAHLBUSH R E,VANMIL B L,MYERS-WARD R L,et al.Basal plane dislocation reduction in4H-SiC epitaxy by growth interruptions[J].Applied Physics Letters,2009,94(4):041916.[44]㊀CAPAN I,BORJANOVIC'V,PIVAC B.Dislocation-related deep levels in carbon rich p-type polycrystalline silicon[J].Solar Energy Materialsand Solar Cells,2007,91(10):931-937.[45]㊀NA M,BAHNG W,JANG H,et al.Effects of stress on the evolution ofΣ-shaped dislocation arrays in a4H-SiC epitaxial layer[J].Journal ofApplied Physics,2021,129(24):245101.[46]㊀LI Z,ZHANG X A,ZHANG Z H,et al.Microstructure of interfacial basal plane dislocations in4H-SiC epilayers[J].Materials Science Forum,2019,954:77-81.[47]㊀NISHIO J,KUDOU C,TAMURA K,et al.C-face epitaxial growth of4H-SiC on quasi-150-mm diameter wafers with high throughput[J].Materials Science Forum,2014,778/779/780:109-112.[48]㊀AOKI M,KAWANOWA H,FENG G,et al.Characterization of bar-shaped stacking faults in4H-SiC epitaxial layers by high-resolutiontransmission electron microscopy[J].Japanese Journal of Applied Physics,2013,52(6R):061301.[49]㊀CAMARDA M,CANINO A,LA MAGNA A,et al.Structural and electronic characterization of(2,33)bar-shaped stacking fault in4H-SiCepitaxial layers[J].Applied Physics Letters,2011,98(5):051915.[50]㊀SUO H,YAMASHITA T,ETO K,et al.Observation of multilayer Shockley-type stacking fault formation during process of epitaxial growth onhighly nitrogen-doped4H-SiC substrate[J].Japanese Journal of Applied Physics,2019,58(2):021001.[51]㊀ASAFUJI R,HIJIKATA Y.Generation of stacking faults in4H-SiC epilayer induced by oxidation[J].Materials Research Express,2018,5(1):015903.[52]㊀DONG L,SUN G S,YU J,et al.Mapping of micropipes and downfalls on4H-SiC epilayers by Candela optical surface analyzer[C]//2012IEEE11th International Conference on Solid-State and Integrated Circuit Technology.October29-November1,2012,Xi'a n,China.IEEE,2013:1-3.[53]㊀KONSTANTINOV A O,HALLIN C,PÉCZ B,et al.The mechanism for cubic SiC formation on off-oriented substrates[J].Journal of CrystalGrowth,1997,178(4):495-504.[54]㊀OKADA T,KIMOTO T,YAMAI K,et al.Crystallographic defects under device-killing surface faults in a homoepitaxially grown film of SiC[J].Materials Science and Engineering:A,2003,361(1/2):67-74.[55]㊀BENAMARA M,ZHANG X,SKOWRONSKI M,et al.Structure of the carrot defect in4H-SiC epitaxial layers[J].Applied Physics Letters,2005,86(2):021905.[56]㊀OKADA T,KIMOTO T,NODA H,et al.Correspondence between surface morphological faults and crystallographic defects in4H-SiChomoepitaxial film[J].Japanese Journal of Applied Physics,2002,41:6320-6326.[57]㊀TSUCHIDA H,KAMATA I,NAGANO M.Investigation of defect formation in4H-SiC epitaxial growth by X-ray topography and defect selectiveetching[J].Journal of Crystal Growth,2007,306(2):254-261.[58]㊀孙国胜,杨㊀霏,柏㊀松,等.4H-碳化硅衬底及外延层缺陷术语[S].T/CASA004.1-2018,北京,2018.SUN G S,YANF F,BO S,et al.4H-Silicon carbide substrate and epitaxial layer defect terms[S].T/CASA004.1-2018,Beijing,2018(in Chinese).[59]㊀POWELL J A,LARKIN D J.Process-induced morphological defects in epitaxial CVD silicon carbide[J].Physica Status Solidi(b),1997,202(1):529-548.[60]㊀KIMOTO T,CHEN Z Y,TAMURA S,et al.Surface morphological structures of4H-,6H-and15R-SiC(0001)epitaxial layers grown bychemical vapor deposition[J].Japanese Journal of Applied Physics,2001,40(5R):3315.[61]㊀KIMOTO T,MIYAMOTO N,MATSUNAMI H.Performance limiting surface defects in SiC epitaxial p-n junction diodes[J].IEEE Transactionson Electron Devices,1999,46(3):471-477.[62]㊀OHTANI N,USHIO S,KANEKO T,et al.Tunneling atomic force microscopy studies on surface growth pits due to dislocations in4H-SiCepitaxial layers[J].Journal of Electronic Materials,2012,41(8):2193-2196.[63]㊀孙国胜,杨㊀霏,柏㊀松,等.4H-SiC衬底及外延层缺陷图谱[S].T/CASA004.2-2018,北京,2018.SUN G S,YANF F,BO S,et al.Defect map of4H-SiC substrate and epitaxial layer[S].T/CASA004.2-2018,Beijing,2018(in Chinese).[64]㊀KUDOU C,ASAMIZU H,TAMURA K,et al.Influence of epi-layer growth pits on SiC device characteristics[J].Materials Science Forum,2015,821/822/823:177-180.。
使用太赫兹快速探测器测量硅少数载流子寿命
第48卷第9期红外与激光工程2019年9月Vol.48No.9Infrared and Laser Engineering Sep.2019使用太赫兹快速探测器测量硅少数载流子寿命张钊，陈勰宇，田震(天津大学精密仪器与光电子工程学院光电信息技术教育部重点实验室太赫兹波研究中心，天津300072)摘要：利用脉冲触发信号在半导体中产生非平衡态载流子的方式，提出一种使用太赫兹连续源和超快速响应探头测量半导体少数载流子寿命的方法，用于表征半导体的瞬态载流子动力学过程。
根据上述设计原理及思路，以泵浦光作为周期性激励信号，搭建出一套工作时间窗口为纳秒到秒量级，时间精度在纳秒量级的非接触式半导体少数载流子寿命测量系统，具有装置简单、操作方便、成本低廉等优点。
使用搭建的系统对不同掺杂类型、不同掺杂浓度、不同厚度单晶硅的非平衡态少数载流子寿命进行测量。
最后，通过改变泵浦光单脉冲能量，对单晶硅光生载流子寿命进行测量，结果表明单晶硅少数载流子寿命随着泵光能量的增大而变长。
该系统所实现的宽工作窗口、高时间精度太赫兹快速过程的探测，可应用于太赫兹领域的快速成像和快速生物响应探测。
关键词：太赫兹；光泵；单晶硅；少数载流子寿命中图分类号：O473文献标志码：A DOI：10.3788/IRLA201948.0919003Measurement of minority carrier lifetime in siliconby high speed terahertz detectorZhang Zhao,Chen Xieyu,Tian Zhen(Center for Terahertz Waves,College of Precision Instrument and Optoelectronics Engineering,and the Key Laboratory of Opto-electronics Information and Technology(Ministry of Education),Tianjin University,Tianjin300072)Abstract:Using pulse trigger signal to generate non-equilibrium carriers in semiconductor,a method for minority carrier lifetime mapping of semiconductor was proposed,with the aid of a terahertz continuous wave source and an ultrafast-response probe,which can apply for characterizing transient carrier dynamics in semiconductor.Based on the above-mentioned design principles,a non-contact minority carrier lifetime measuring system was set up by using the optical pump as the periodic excitation,whose time window was from nanosecond to second and temporal resolution was the order of nanosecond.The system owned various advantages,such as simple device,convenient operation and low cost.The non-equilibrium minority carrier lifetime of monocrystalline silicon with different doping types,different doping concentration,and different thickness were measured by using our system.Finally,the photo-generated carrier lifetime of the monocrystalline silicon was measured through changing the optical pump power.Result shows that the收稿日期：2019-05-05；修订日期：2019-06-03基金项目：国家重点研发计划(2017YFA0701004)；国家自然科学基金(61722509，61675145，61735012)作者简介：张钊(1994-)，女，硕士生，主要从事太赫兹器件及系统方面的研究。
控制万物的芯片作文
控制万物的芯片作文英文回答：Controlling everything with a chip is a concept that has fascinated scientists and technologists for decades. The idea of having a tiny, powerful chip that can control and monitor every aspect of our lives is both exciting and terrifying. On one hand, it promises convenience and efficiency, but on the other hand, it raises concerns about privacy and autonomy.Imagine a world where every device, every appliance, and even every individual is connected to a central chip. This chip would have the ability to collect and analyze data, make decisions, and communicate with other chips. It would be the ultimate control center, dictating how our homes, our cities, and even our bodies function.With such a chip, our lives would become incredibly convenient. Imagine waking up in the morning and havingyour chip automatically brew your favorite coffee, adjust the temperature in your house, and even select the perfect outfit for the day based on the weather forecast. Throughout the day, the chip would monitor your health, reminding you to exercise, eat healthy, and take breaks when needed. It would also handle mundane tasks like paying bills, scheduling appointments, and even driving your car.However, this level of control also raises concerns about privacy and autonomy. With a chip that knows everything about us, there is a risk of our personal information being accessed and misused. Moreover, if everything is controlled by a central chip, we may lose the ability to make decisions for ourselves. Our lives would become dictated by algorithms and data analysis, leaving little room for spontaneity and personal choice.Furthermore, the idea of a chip controlling everything also raises ethical questions. Who would have access tothis technology? Would it be available to everyone or only to those who can afford it? And what would happen if the chip malfunctions or falls into the wrong hands? Thepotential for abuse and manipulation is significant.In conclusion, the concept of controlling everything with a chip is both exciting and concerning. While it promises convenience and efficiency, it also raises concerns about privacy, autonomy, and ethical implications. As technology continues to advance, it is crucial to carefully consider the potential consequences and ensure that any implementation of such a chip is done in a waythat respects individual rights and values.中文回答：控制万物的芯片是一个让科学家和技术专家们着迷的概念，数十年来一直如此。
触摸芯片介绍英文作文
触摸芯片介绍英文作文下载温馨提示:该文档是我店铺精心编制而成，希望大家下载以后，能够帮助大家解决实际的问题。
文档下载后可定制随意修改，请根据实际需要进行相应的调整和使用，谢谢!并且，本店铺为大家提供各种各样类型的实用资料，如教育随笔、日记赏析、句子摘抄、古诗大全、经典美文、话题作文、工作总结、词语解析、文案摘录、其他资料等等，如想了解不同资料格式和写法，敬请关注!Download tips: This document is carefully compiled by theeditor. I hope that after you download them,they can help yousolve practical problems. The document can be customized andmodified after downloading,please adjust and use it according toactual needs, thank you!In addition, our shop provides you with various types ofpractical materials,such as educational essays, diaryappreciation,sentence excerpts,ancient poems,classic articles,topic composition,work summary,word parsing,copyexcerpts,other materials and so on,want to know different data formats andwriting methods,please pay attention!Touch chips are really cool. They can make our devices more sensitive and responsive. You just touch the screen or a specific area, and things happen. It's like magic!These chips are very important in today's technology. They are used in phones, tablets, and other electronic gadgets. They make it easy for us to interact with our devices.The technology behind touch chips is amazing. It allows for precise control and quick reactions. You don't even have to think about it, it just works.And they keep getting better and better. Newer versions are more accurate and can do more things. It's exciting to think about what they will be able to do in the future.。
Minority Carrier Lifetime in As-Grown Germanium Doped Czochralski Silicon
CHIN.PHYS.LETT.Vol.25,No.2(2008)651 Minority Carrier Lifetime in As-Grown Germanium Doped Czochralski Silicon∗ZHU Xin(朱鑫),YANG De-Ren(杨德仁)∗∗,LI Ming(李明),CHEN Tao(陈涛),WANG Lei(汪雷),QUE Duan-Lin(阙端麟)State Key Laboratory of Silicon Materials and Department of Material Science and Engineering,Zhejiang University,Hangzhou310027(Received11October2007)The minority carrier lifetime of as-grown germanium-doped Czochralski(GCZ)silicon wafers doped with germa-nium concentrations[Ge]=1016–1018cm−3is investigated in comparison with conventional CZ silicon samples.It is found that the lifetime distribution along the ingot changes with the variation of[Ge].There is a critical value of[Ge]=1016cm−3beyond which Ge can obviously influence the lifetime of as-grown ingots.This phenomenon is considered to be associated with the competition or combination between the oxygen related thermal donors (TDs)and electrically active Ge-related complexes.The related formation mechanisms and distributions are also discussed.PACS:,61.72.Yx,Germanium doping in silicon can suppress crystal-oriented particles,[1]enhance oxygen precipitations (OPs),[2,3]and improve the mechanical strength of wafers.[4]Various complexes have been proposed to ex-plain the phenomena related.However,the complexes existing in germanium-doped Czochralski(GCZ)sil-icon at high temperatures have not yet been verified due to their inactive properties or tiny density.Mean-while,minority carrier lifetime has been widely uti-lized to monitor the processes of semiconductor due to its sensitivity to trace impurities and defects with a detective limit even down to109cm−3levels.[5]Up to now,there are few reports on the lifetime in GCZ silicon.In this Letter,we investigate the effects of Ge on the lifetime in the as-grown CZ silicon ingot with the microwave photo-conductance decay(MW-PCD) and low temperature infrared(LT-IR)spectra tech-niques.Four 100 oriented P-type silicon ingots with5-inch diameter doped with and without Ge were grown under the same conditions by the Czochralski method. The densities[Ge]in Ge-doped silicon are calculated to be,respectively,1016cm−3(GCZ1),1017cm−3 (GCZ2),and1018cm−3(GCZ3)at the head end us-ing the effective segregation coefficient k=0.33.[Ge] at80%axial position is roughly3times of that at 20%axial position.For simplification,[Ge]in the fol-lowing descriptions is just assigned to the density at the head end of the ingots.Wafers with the same thickness of800µm were picked out from the position 20%,50%and80%lengths of ingot.The resistiv-ity was between8Ω·cm and10Ω·cm.The concen-tration of interstitial oxygen was between0.8×1018–01×1018cm−3,and the density of carbon was lower than5×1015cm−3.Wafers were chemical polished and immediately processed to grow80nm SiN x layers on both sides of a plasma-enhanced chemical vapour deposition(PECVD)system with a substrate temper-ature of300◦C.Then the effective minority carrier life-time of the samples was tested by a Semilab WT2000 MW-PCD system.The average lifetime of the central 1×1cm2area in the map was used.Figure1shows the dependence of lifetime on the axial position of ingot.It can be seen that the lifetime of the GCZ ingots are in the range of100–900µs.Fur-thermore,the lifetime in the GCZ1silicon increases along the ingot,which is similar to the ingot without Ge doping.However,the lifetimes in the GCZ2and GCZ3silicon appear a V-shaped distribution and a decreasing tendency,respectively.With the excellent passivation of SiN x layers,[6] the lifetime tested is the bulk SRH lifetime,[7]which mainly reflects the recombination behaviour of defects. Because absolute capture cross sections of the defects are unknown,the relation between defect density and lifetime is expressed by an effective defect density N∗t, i.e.N∗t=1τ=ii=1v thσn,i N t,i,(1)whereτis the lifetime from tests.In a p-type silicon, it is related to the electron capture cross sectionsσn,i of the combination centres,their density N t,i,and the carrier thermal velocities v th.N∗t can be used for com-parisons among the samples even through the values should be taken care of.Figure2shows the relationship between N∗t and the Ge content,respectively,at the head,the middle∗Supported by the National Natural Science Foundation of China under Grant No50572094,the Programme for Cheung Kong Scholars and Innovative Research Team in University(PCSIRT),and Key Project of Science and Technology Department of Zhejiang Province under Grant No2006C11275.∗∗Email:mseyang@c 2008Chinese Physical Society and IOP Publishing Ltd652ZHU Xin et al.Vol.25and the tail of the silicon ingots.It illustrates that N ∗t decreases with [Ge]in the head end of ingot,while it increases slowly in the middle and fast in the tail end of the ingots.It obviously shows an inhibition of Ge on the defects at the head end of the ingot,but a promotion in tail end of the ingot.Fig.1.Lifetime distributions along the growth direction of the silicon ingots doped with and without germanium.The Ge densities at the head end of the GCZ1,GCZ2and GCZ3silicon ingots are about 1016,1017and 1018cm −3,respectively.Fig.2.Effective density N ∗tof the trap levels versus [Ge]of the samples.N ∗tis calculated as the inverse of lifetime data from Fig.1.The tendency of N ∗t in the head end is consistent with the dependence of the TDs on [Ge],as shown in Fig.3,suggesting strongly a TDs dominating be-haviour.The relationship between the concentration of TDs ([TD])and [Ge]is in agreement with the re-ported results.[8,9]Figure 3shows the LT-IR spectra of the samples with [Ge]=1016,1017and 1018cm −3,respectively.The peaks are assigned to the thermal double donors (TDDs)by Wagner and Hage.[10]The samples were annealed at 450◦C to simulate a pro-longed process of cooling,and a 650◦C/30min pre-treatment was used to remove the grow-in TDs.The total concentration of TDs was calculated according to ASTM F723-88with the resistivity before and af-ter the annealing at 450◦C.Fig.3.LT-IR spectra of the samples GCZ1,GCZ2and GCZ3,respectively.All the samples are treated at 650◦C/30min +450◦C/6h annealing.Inset:the total donor concentration [TD]versus [Ge].Meanwhile,the complexes formed at high temper-ature during the cooling of the ingot are responsible for the lifetime in the tail end.When [Ge]gets up to 1018cm −3,the lifetime of ingot is totally dominated by the Ge-related complexes,which is attributed to the most elementary and electrically active Ge-vacancyNo.2ZHU Xin et al.653(GeV)[11,12]and GeVO (GeV with an additional oxy-gen atom).[13]In fact,Ge-related complexes are always changing during the cooling of ingot.Yang et al .[14]have,based on their experiments,pointed out that the Ge atom can firstly capture a mono-vacancy forming GeV com-plex typically beyond 1100◦C,and then the interstitial oxygen atoms to form GeVO or even larger complexes GeVO n (n ≥2),which can act as the nuclei of the OPs [15]and are supposed to be electrically inactive.Even at lower temperature for the formation of TDs,GeV is supposed to capture oxygen dimer,the precur-sor of the TDs,[16]to form GeVO 2and thus to inhibit the formation of TDs.[17]Consequently,electrically ac-tive complexes increase along the axis of GCZ3ingot doped with [Ge]=1018cm −3,which results in the decreasing lifetime distribution.Unfortunately,the grown-in Ge-related complexes are failed to be de-tected by DLTS in the as-grown silicon wafers mostlydue to their tiny absolute density.It should be noted that the grow-in tiny oxy-gen precipitates (OPs)[18]are not enough to induce extended defects,so they have little gettering abil-ity.As a result,they trend to perform electrical neutrality.[19]Furthermore,they have a positive de-pendence on [Ge],[8]which is opposite to the tendency of N ∗t .Thus the grow-in OPs are excluded from the dominating factors.Based on the above discussions,the effects of TDs and Ge-related complexes on the distribution of N ∗t is schematically shown in Fig.4.It can be seen that in all Ge-doped ingots,the TD-related levels decrease by the axial position of ingot,while the Ge-related levels increase.Their relative densities could be con-trolled by the level of Ge-doping,and the competing results between them would determine the tendency of lifetime along the ingot.Fig.4.Schematic diagram on the distribution of effective traps (line with symbol)with the contributions of both TDs (dashed)and the Ge-related complexes (dot-dashed).In summary,Ge doping could have strong effects on the lifetime of as-grown silicon ingot.Apparently 1016cm −3is a critical value of [Ge]beyond which Ge can obviously influence on the lifetime of as-grown in-got.The effects of Ge-doping on lifetime involve both oxygen atoms and vacancies.[TD]decreases by the axial position of ingot,which plays a major role in both Ge-clean and lightly Ge-doped as-grown CZ sil-icon ingot.Meanwhile,electrically active Ge-related complexes involving vacancies act as the recombina-tion levels with an increasing density by the axial po-sition of ingot.The effects on lifetime of such two kinds of levels are comparable to each other within the range of [Ge]=1016–1018cm −3.As a result,it is apparent that the lifetime of ingots distributes highly sensitive to the level of Ge-doping.References[1]Carbonaro C M,Fiorentini V and Bernardini F 2002Phys.Rev.B 66233201[2]Yu X et al 2003J.Cryst.Growth 250359[3]Yang D et al 2002J.Cryst.Growth 243371[4]Taishi T,Huang X,Yonenaga I and Hoshikawa K 2003Mater.Sci.Semicond.Proc.5409[5]Palais O,Yakimov E and Martinuzzi S 2002Mater.Sci.Engin.B 91/92216[6]Touˇs ka J et al 2006J.Appl.Phys .100113716[7]Schroder D K 1997IEEE Trans.Electron.Devices 44160[8]Li H et al 2004J Phys:Condens Matter 165745[9]Hild E,Gaworzewski P,Franz M and Pressel K 1998Appl.Phys.Lett.721362[10]Wagner P and Hage J 1989Appl.Phys.A:Solid.Surf .49123[11]Watkins G D 2000Mater.Sci.Semicond.Processing 3227[12]Budtz-Jorgensen C V,Kringhoj P and Nylandsted LarsenA 1998Phys.Rev.B 581110[13]Markevich V P et al 2004Phys.Rev .B 69125218[14]Yang D and Chen J 2005Defect and Diffusion Forum 242-244169[15]Chen J et al 2006J.Cryst.Growth 29166[16]Murin L I,Hallberg T,Markevich V P and Lindstr¨o J L1998Phys.Rev.Lett.8093[17]Zhu X et al 2008Solid State Phenomena 131-133393[18]Kobayashi S 1997J.Cryst.Growth 174163[19]Lee B Y,Hwang D H and Kwon O J 1998Jpn.J.Appl.Phys.37L902。
光伏工艺流程英语
IntroductionThe photovoltaic (PV) industry, an essential component of the global renewable energy landscape, is characterized by its continuous pursuit of high-quality and high-standard manufacturing processes. These processes are critical to ensuring the efficiency, reliability, and longevity of solar modules, which directly impact their overall performance and return on investment. This comprehensive analysis delves into the intricate steps involved in the PV manufacturing process, emphasizing the multi-faceted strategies employed to maintain and enhance product quality and adherence to stringent standards.1. Silicon Feedstock ProcessingThe PV manufacturing process begins with the procurement and refinement of silicon feedstock, the primary raw material for most solar cells. High-quality monocrystalline or multicrystalline silicon is obtained through processes such as the Czochralski (CZ) method or the directional solidification technique. These methods ensure the production of silicon ingots with low impurity levels and optimized crystal structures, vital for maximizing cell efficiency. Rigorous quality control measures, including in-line monitoring and post-processing inspections, are implemented to verify the purity, resistivity, and structural integrity of the silicon.2. Wafer FabricationSilicon ingots are sliced into thin wafers, typically 150-200 micrometers thick, using wire saws or diamond-coated blades. The wafer fabrication stage involves precise control over wafer thickness, flatness, and surface roughness to minimize optical losses and ensure uniformity across the production batch. Advanced texturing techniques, such as alkaline etching or laser doping, are applied to create microstructures on the wafer surface, enhancing light absorption and reducing reflectance. Quality control at this stage includes visual inspections, edge isolation, and electrical testing to identify and weed out defective wafers.3. Solar Cell ProcessingSolar cell processing transforms the silicon wafers into functional devices capable of converting sunlight into electricity. Key steps include:a) Surface Passivation: High-quality dielectric films, such as silicon nitride or aluminum oxide, are deposited on both sides of the wafer to reduce surface recombination and improve minority carrier lifetime, thereby enhancing cell efficiency.b) Diffusion: Phosphorus or boron dopants are introduced into the wafer to form the p-n junction, the heart of the solar cell where photogenerated electrons and holes separate and generate current. Precise control over diffusion temperature, time, and gas concentration is crucial to achieve the desired junction depth and sheet resistance.c) Metallization: Fine-line screen printing or advanced plating techniques are used to deposit metal contacts (usually silver or aluminum) on the front and back surfaces of the cell. The design and layout of these contacts significantly influence cell efficiency by minimizing shading losses and optimizing current collection.d) Anti-Reflection Coating (ARC): A thin layer of silicon nitride or other materials is applied to the front surface of the cell, further reducing surface reflection and enhancing light trapping.Throughout this stage, rigorous quality control measures are in place, including real-time process monitoring, in-line metrology, and periodic sampling for detailed characterization and analysis. These measures ensure compliance with industry standards like IEC 61215 and IEC 61730, which govern the performance, safety, and durability of PV modules.4. Module AssemblyHigh-quality PV modules are assembled from individual cells, encapsulated between ethylene-vinyl acetate (EVA) sheets and protected by a durable glass cover and a weather-resistant backsheet. Stringing the cells in series, soldering interconnects, and laminating the components under vacuum and elevated temperatures ensure electrical connectivity, mechanical stability, andenvironmental protection. Quality control during module assembly encompasses visual inspections, electroluminescence imaging, and flash testing to assess cell-to-cell variations, detect micro-cracks or hotspots, and verify power output and performance parameters.5. Reliability Testing and CertificationTo meet high-standard requirements, PV modules undergo a battery of rigorous reliability tests simulating various environmental and stress conditions they may encounter during their service life. These tests, as outlined in international standards like IEC 61215, IEC 61730, and UL 1703, include thermal cycling, humidity-freeze, damp heat, mechanical load, and potential-induced degradation (PID) tests. Successful completion of these tests earns modules certifications from recognized bodies like TÜV Rheinland, UL, or Intertek, providing assurance of their long-term performance and durability.6. Supply Chain Management and TraceabilityEnsuring high-quality, high-standard PV products also necessitates robust supply chain management and traceability systems. Manufacturers collaborate closely with suppliers to verify the quality and sustainability of raw materials, components, and auxiliary services. Advanced digital platforms enable end-to-end tracking of materials and processes, facilitating quick identification and resolution of quality issues, adherence to international regulations, and fulfillment of customer-specific requirements.ConclusionThe high-quality, high-standard PV manufacturing process is a testament to the industry's commitment to delivering efficient, reliable, and long-lasting solar energy solutions. From the meticulous processing of silicon feedstock to the rigorous testing and certification of finished modules, each stage is infused with a multi-dimensional approach to quality control, technological innovation, and adherence to international standards. As the global shift towards renewable energy accelerates, the ongoing refinement and optimization of this complex process will continue to drive advancements in solar technology, fostering amore sustainable and resilient energy future.。
惠普企业 OfficeConnect 1410 交换机系列说明书
Product overviewHPE OfficeConnect 1410 Switch Series comprises unmanaged Gigabit Ethernet and Fast Ethernet switches, designed for small businesses looking for entry-level low-cost networking solutions that come with a limited lifetime warranty. The series consists of nine models with flexible mounting options to meet different network switching needs. All models have quality of service (QoS) support and IEEE 802.3x flow control features that provide outstanding data efficiency.Simplified plug-and-play convenience is enabled by features such as auto-MDIX and auto-speed negotiation. Hewlett Packard Enterprise has innovated and combined the latest advances in silicon technology to bring you some of the most power-efficient switches—11410 24G R, 1410 16 and 1410 24 models. are advanced IEEE 802.3az-compliant unmanaged Gigabit and Fast Ethernet switches. The switches come with built-in green features and HPE Limited Lifetime Warranty, making the series the right choice for organizations seeking a networking solution that’s both economical and reliable.A summary of the highlights of the 1410 Switch Series:• Unmanaged Gigabit Ethernet and Fast Ethernet switches • Green features for low power consumption • Fan-less design for silent operation • QoS support• Limited Lifetime warrantyHPE OfficeConnect 1410 Switch SeriesData sheetFeatures and benefitsQoS• IEEE 802.1p prioritizationDelivers data to devices, based on the priority and type of traffic• DiffServ Code Point (DSCP) supportAllows real-time traffic prioritization, based on L3 TOS/DSCP parametersConnectivity• Auto-MDIXProvides automatic adjustments for straight-through or crossover cables on all 10/100 and 10/100/1000 portsPerformance• NEW Energy-efficient Ethernet supportSupports new IEEE 802.3az standard; and allows lower power consumption, when operated with IEEE-compliant client devices in 100 Mb/s mode only (JG708A, J9662A, and J9663A)• Half-/full-duplex auto-negotiating capability on every portDoubles the throughput of every port• NEW Jumbo frame supportAllows frames up to 9,216 bytes to be switched through the network (Gigabit Ethernet models)• Mini jumbo-frame supportAllows frames up to 2,048 bytes to be switched through the network, which supports large data transfers (J9662A and J9663A)Ease of use• UnmanagedProvides plug-and-play simplicity• Comprehensive LED display with per-port indicatorsProvides an at-a-glance view of the status, activity, speed, and full-duplex operation of the switches • Flow controlHelps ensure reliable communications during full-duplex operation• Auto-speed negotiationSelects individual port speed automatically, depending on client capabilities; removing the need for manual intervention enables simple plug-and-play operationFlexibility• Fan-less designEnables quiet operation for deployment in open spaces• NEW Internal power supplyDelivers operational convenience and an environment suitable for business operations (JG708A, J9561A, and JD986B)Warranty and support• Limited Lifetime Warranty• HPE OfficeConnect 1410 Switch Series includes a Limited Lifetime Warranty. This warranty provides advance hardware replacement with next business day shipment in most countries, limited 24x7 telephone support available from HPE for the first 90 days, and limited electronic and business hours telephone support is available from HPE for the entire warranty period. See /networking/warrantysummary for warranty and support information included with your product purchase.HPE OfficeConnect 1410 Switch SeriesSPECIFICATIONS HPE OfficeConnect 1410 8G Switch(J9559A)HPE OfficeConnect 1410 16G Switch(J9560A)HPE OfficeConnect 1410 24G R Switch(JG708A)Ports8 RJ-45 autosensing 10/100/1000ports (IEEE 802.3 Type 10BASE-T,IEEE 802.3u Type 100BASE-TX,IEEE 802.3ab Type 1000BASE-T);Media Type: Auto-MDIX; Duplex:10BASE-T/100BASE-TX: half or full;1000BASE-T: full onlySupports a maximum of 8 autosensing10/100/1000 ports16 RJ-45 autosensing 10/100/1000ports (IEEE 802.3 Type 10BASE-T,IEEE 802.3u Type 100BASE-TX,IEEE 802.3ab Type 1000BASE-T);Media Type: Auto-MDIX; Duplex:10BASE-T/100BASE-TX: half or full;1000BASE-T: full onlySupports a maximum of 16 autosensing10/100/1000 ports24 RJ-45 autosensing 10/100/1000ports (IEEE 802.3 Type 10BASE-T,IEEE 802.3u Type 100BASE-TX,IEEE 802.3ab Type 1000BASE-T);Media Type: Auto-MDIX; Duplex:10BASE-T/100BASE-TX: half or full;1000BASE-T: full onlySupports a maximum of 24 autosensing10/100/1000 portsPhysical characteristicsWeight6.14(w) x 3.8(d) x 0.96(h) in(15.6 x 9.65 x 2.45 cm)0.74 lb (0.34 kg)8.21(w) x 4.41(d) x 1.73(h) in(20.85 x 11.2 x 4.4 cm) (1U height)1.43 lb (0.65 kg)17.32(w) x 6.81(d) x 1.73(h) in(44 x 17.3 x 4.4 cm) (1U height)6.61 lb (3 kg)Memory and processor 4 Kb EEPROM capacity;packet buffer size: 192 KB512 Kb flash; packet buffer size: 512 KB 1 MB flash; packet buffer size: 512 KBMounting Wall, desktop and under-table mounting Mounts in an EIA standard 19-inch telcorack (hardware included); wall, desktopand under-table mountingMounts in an EIA standard 19-inch telco rack(hardware included); desktop mountingPerformance100 Mb Latency1000 Mb LatencyThroughputSwitching capacityMAC address table size< 3.6 µs (LIFO 64-byte packets)< 1.2 µs (LIFO 64-byte packets)up to 11.9 million pps (64-byte packets)16 Gb/s4096 entries< 8.0 µs (LIFO 64-byte packets)< 3.6 µs (LIFO 64-byte packets)up to 23.8 million pps (64-byte packets)32 Gb/s8192 entries< 8.0 µs (LIFO 64-byte packets)< 3.6 µs (LIFO 64-byte packets)35.7 million pps (64-byte packets)48 Gb/s8192 entriesEnvironmentOperating temperatureOperating relative humidityNon-operating/Storage temperatureNon-operating/Storage relative humidityAltitudeAcoustic32°F to 104°F (0°C to 40°C)15% to 95% @ 104°F (40°C), noncondensing-40°F to 158°F (-40°C to 70°C)15% to 90% @ 149°F (65°C), noncondensingup to 10,000 ft (3 km)Power: 0 dB No fan32°F to 104°F (0°C to 40°C)15% to 95% @ 104°F (40°C), noncondensing-40°F to 158°F (-40°C to 70°C)15% to 90% @ 149°F (65°C), noncondensingup to 10,000 ft (3 km)Power: 0 dB No fan32°F to 104°F (0°C to 40°C)5% to 95% @ 104°F (40°C), noncondensing-40°F to 158°F (-40°C to 70°C)15% to 90% @ 149°F (65°C), noncondensingup to 16,404 ft (5 km)Power: 0 dB No fanElectrical characteristicsFrequencyMaximum heat dissipationVoltageCurrentMaximum power rating50/60 Hz41 BTU/hr (43.26 kJ/hr)100-240 VAC1.0 A12 WNotes:Maximum power rating and maximumheat dissipation are the worst-casetheoretical maximum numbers providedfor planning the infrastructure withfully loaded PoE (if equipped), 100%traffic, all ports plugged in, and allmodules populated.The exact input voltage and frequencyrating are determined by the specificpower adaptor part number ordered.Please select the correct power adaptorcountry option.50/60 Hz44 BTU/hr (46.42 kJ/hr)100-240 VAC1.1 A13 WNotes:Maximum power rating and maximumheat dissipation are the worst-casetheoretical maximum numbers providedfor planning the infrastructure withfully loaded PoE (if equipped), 100%traffic, all ports plugged in, and allmodules populated.The exact input voltage and frequencyrating are determined by the specificpower adaptor part number ordered.Please select the correct power adaptorcountry option.50/60 Hz55 BTU/hr (58 kJ/hr)100-240 VAC0.3 A16 WNotes:Maximum power rating and maximumheat dissipation are the worst-casetheoretical maximum numbers providedfor planning the infrastructure withfully loaded PoE (if equipped), 100%traffic, all ports plugged in, and allmodules populated.This model provides internal powersupply. Please select the correct powercord country option.SPECIFICATIONS HPE OfficeConnect 1410 8G Switch(J9559A)HPE OfficeConnect 1410 16G Switch(J9560A)HPE OfficeConnect 1410 24G R Switch(JG708A)Safety CSA 22.2 No. 60950; EN 60950/IEC 60950; UL 60950-1 CSA 22.2 No. 60950; UL 60950-1;IEC 60950-1; EN 60950-1CSA 22.2 No. 60950; UL 60950-1;IEC 60950-1; EN 60950-1Emissions FCC Rules Part 15, Subpart B Class A FCC Rules Part 15, Subpart B Class A FCC Rules Part 15, Subpart B Class A ImmunityGenericENESDRadiatedEFT/BurstSurgeConductedPower frequency magnetic field Voltage dips and interruptions HarmonicsFlicker EN 55022 CISPR 22EN 55024, CISPR 24IEC 61000-4-2IEC 61000-4-3IEC 61000-4-4IEC 61000-4-5IEC 61000-4-6IEC 61000-4-8IEC 61000-4-11IEC 61000-3-2IEC 61000-3-3EN 55022 CISPR 22EN 55024, CISPR 24IEC 61000-4-2IEC 61000-4-3IEC 61000-4-4IEC 61000-4-5IEC 61000-4-6IEC 61000-4-8IEC 61000-4-11IEC 61000-3-2IEC 61000-3-3EN 55022 CISPR 22EN 55024, CISPR 24IEC 61000-4-2IEC 61000-4-3IEC 61000-4-4IEC 61000-4-5IEC 61000-4-6IEC 61000-4-8IEC 61000-4-11IEC 61000-3-2IEC 61000-3-3NotesIEEE 802.3az Energy Efficient Ethernet protocol is supported by the HPE 1410-24G-R (JG708A), HPE 1410-16 (J9662A) and HPE 1410-24 (J9663A) Switches.Services Refer to the Hewlett PackardEnterprise website at/networking/services fordetails on the service-level descriptionsand product numbers. For details aboutservices and response times in your area,please contact your local Hewlett PackardEnterprise sales office. Refer to the Hewlett PackardEnterprise website at/networking/services fordetails on the service-level descriptionsand product numbers. For details aboutservices and response times in your area,please contact your local Hewlett PackardEnterprise sales office.Refer to the Hewlett PackardEnterprise website at/networking/services fordetails on the service-level descriptionsand product numbers. For details aboutservices and response times in your area,please contact your local Hewlett PackardEnterprise sales office.(CONTINUED)HPE OfficeConnect 1410 Switch SeriesSPECIFICATIONSHPE OfficeConnect 1410 24G Switch (J9561A)HPE OfficeConnect 1410 8 Switch (J9661A)HPE OfficeConnect 1410 16 Switch (J9662A)Ports22 RJ-45 autosensing 10/100/1000 ports (IEEE 802.3 Type 10BASE-T, IEEE 802.3u Type 100BASE-TX, IEEE802.3ab Type 1000BASE-T); Media Type: Auto-MDIX; Duplex: 10BASE-T/100BASE-TX: half or full; 1000BASE-T: full only2 dual-personality ports; each port can be used as either an RJ-45 10/100/1000 port (IEEE 802.3 Type 10BASE-T, IEEE 802.3u Type 100BASE-TX, IEEE 802.3ab 1000BASE-T Gigabit Ethernet) or an open mini-GBIC slot (for use with mini-GBIC transceivers)Supports a maximum of 24 Gigabit Ethernet ports8 RJ-45 autosensing 10/100 ports(IEEE 802.3 Type 10BASE-T, IEEE 802.3u Type 100BASE-TX); Duplex: half or full Supports a maximum of 8 autosensing 10/100 ports16 RJ-45 autosensing 10/100 ports(IEEE 802.3 Type 10BASE-T, IEEE 802.3u Type 100BASE-TX); Duplex: half or full Supports a maximum of 16 autosensing 10/100 portsPhysical characteristics Weight13.23(w) x 6.65(d) x 1.73(h) in (33.6 x 16.9 x 4.4 cm) (1U height)2.98 lb (1.35 kg)6.14(w) x 3.74(d) x 0.97(h) in (15.6 x 9.5 x 2.46 cm) 0.74 lb (0.34 kg)8.21(w) x 4.21(d) x 1.73(h) in(20.85 x 10.69 x 4.39 cm) (1U height)1.43 lb (0.65 kg)Memory and processor 512 Kb flash; packet buffer size: 512 KB 16 Kb EEPROM; packet buffer size: 96 KB 16Kb EEPROM; packet buffer size: 2 Mb MountingMounts in an EIA standard 19-inch telco rack (hardware included); wall, desktop and under-table mountingWall, desktop and under-table mountingMounts in an EIA standard 19-inch telco rack (hardware included) wall, desktop and under-table mountingPerformance 100 Mb Latency 1000 Mb Latency ThroughputSwitching capacity MAC address table size< 8.0 µs (LIFO 64-byte packets) < 3.6 µs (LIFO 64-byte packets)up to 35.7 million pps (64-byte packets) 48 Gb/s 8192 entries< 3.7 µs (LIFO 64-byte packets) up to 1.1 million pps (64-byte packets) 1.6 Gb/s 1024 entries< 10.6 µs (LIFO 64-byte packets) up to 2.3 million pps (64-byte packets)3.2 Gb/s 8192 entriesEnvironmentOperating temperature Operating relative humidityNon-operating/Storage temperature Non-operating/Storage relative humidity Altitude Acoustic32°F to 104°F (0°C to 40°C)15% to 95% @ 104°F (40°C), noncondensing -40°F to 158°F (-40°C to 70°C)15% to 90% @ 149°F (65°C), noncondensing up to 10,000 ft (3 km) Power: 0 dB No fan 32°F to 104°F (0°C to 40°C)15% to 95% @ 104°F (40°C), noncondensing -40°F to 158°F (-40°C to 70°C)15% to 90% @ 149°F (65°C), noncondensing up to 10,000 ft (3 km) Power: 0 dB No fan 32°F to 104°F (0°C to 40°C)5% to 95% @ 104°F (40°C), noncondensing -40°F to 158°F (-40°C to 70°C)15% to 90% @ 149°F (65°C), noncondensing up to 16,404 ft (5 km)Power: 0 dB No fanSPECIFICATIONS HPE OfficeConnect 1410 24G Switch(J9561A)HPE OfficeConnect 1410 8 Switch(J9661A)HPE OfficeConnect 1410 16 Switch(J9662A)Electrical characteristicsFrequencyMaximum heat dissipation VoltageDC voltageCurrentMaximum power rating 50/60 Hz75 BTU/hr (79.13 kJ/hr)100-240 VAC0.3 A22 WNotes:Maximum power rating and maximumheat dissipation are the worst-casetheoretical maximum numbers providedfor planning the infrastructure withfully loaded PoE (if equipped), 100%traffic, all ports plugged in, and allmodules populated.This model provides internal powersupply. Please select the correct powercord country option.50/60 Hz13 BTU/hr (13.72 kJ/hr)100-240 VAC12 V0.3 A3.6 WNotes:Maximum power rating and maximumheat dissipation are the worst-casetheoretical maximum numbers providedfor planning the infrastructure withfully loaded PoE (if equipped), 100%traffic, all ports plugged in, and allmodules populated.The exact input voltage and frequencyrating are determined by the specificpower adaptor part number ordered.Please select the correct power adaptorcountry option.50/60 Hz13 BTU/hr (13.72 kJ/hr)100-240 VAC12 V0.3 A3.6 WNotes:Maximum power rating and maximumheat dissipation are the worst-casetheoretical maximum numbers providedfor planning the infrastructure withfully loaded PoE (if equipped), 100%traffic, all ports plugged in, and allmodules populated.The exact input voltage and frequencyrating are determined by the specificpower adaptor part number ordered.Please select the correct power adaptorcountry option.Safety CSA 22.2 No. 60950; UL 60950-1;IEC 60950-1; EN 60950-1UL 60950-1; CSA 22.2 60950-1;IEC 60950-1:2005;EN 60950-1:2006 + A11:2009UL 60950-1; CSA C22.2 60950-1;IEC 60950-1:2005;EN 60950-1:2006 + A11:2009Emissions FCC Rules Part 15, Subpart B Class A FCC Rules Part 15, Subpart B Class A FCC Rules Part 15, Subpart B Class A ImmunityGenericENESDRadiatedEFT/BurstSurgeConductedPower frequency magnetic field Voltage dips and interruptions HarmonicsFlicker EN 55022 CISPR 22EN 55024, CISPR 24IEC 61000-4-2IEC 61000-4-3IEC 61000-4-4IEC 61000-4-5IEC 61000-4-6IEC 61000-4-8IEC 61000-4-11IEC 61000-3-2IEC 61000-3-3EN 55022 CISPR 22EN 55024, CISPR 24IEC 61000-4-2IEC 61000-4-3IEC 61000-4-4IEC 61000-4-5IEC 61000-4-6IEC 61000-4-8IEC 61000-4-11IEC 61000-3-2IEC 61000-3-3EN 55022 CISPR 22EN 55024, CISPR 24IEC 61000-4-2IEC 61000-4-3IEC 61000-4-4IEC 61000-4-5IEC 61000-4-6IEC 61000-4-8IEC 61000-4-11IEC 61000-3-2IEC 61000-3-3Notes:Use only supported genuine Hewlett Packard Enterprise mini-GBICs with your switch.IEEE 802.3az Energy Efficient Ethernet protocol is supported by the HPE 1410-24G-R (JG708A), HPE 1410-16 (J9662A) and HPE 1410-24 (J9663A) Switches.(CONTINUED)SPECIFICATIONS HPE OfficeConnect 1410 24G Switch(J9561A)HPE OfficeConnect 1410 8 Switch(J9661A)HPE OfficeConnect 1410 16 Switch(J9662A)Services Refer to the Hewlett PackardEnterprise website at/networking/services fordetails on the service-level descriptionsand product numbers. For details aboutservices and response times in your area,please contact your local Hewlett PackardEnterprise sales office. Refer to the Hewlett PackardEnterprise website at/networking/services fordetails on the service-level descriptionsand product numbers. For details aboutservices and response times in your area,please contact your local Hewlett PackardEnterprise sales office.Refer to the Hewlett PackardEnterprise website at/networking/services fordetails on the service-level descriptionsand product numbers. For details aboutservices and response times in your area,please contact your local Hewlett PackardEnterprise sales office.(CONTINUED)HPE OfficeConnect 1410 Switch SeriesSPECIFICATIONS HPE OfficeConnect 1410-24 Switch(J9663A)HPE OfficeConnect 1410-24-R Switch(JD986B)HPE OfficeConnect 1410-24-2GSwitch (J9664A)Ports24 RJ-45 autosensing 10/100 ports(IEEE 802.3 Type 10BASE-T, IEEE 802.3uType 100BASE-TX, IEEE 802.3abType 1000BASE-T); Duplex:10BASE-T/100BASE-TX: half or full;1000BASE-T: full onlySupports a maximum of 24 autosensing10/100 ports24 RJ-45 autosensing 10/100 ports(IEEE 802.3 Type 10BASE-T, IEEE 802.3uType 100BASE-TX, IEEE 802.3abType 1000BASE-T); Duplex:10BASE-T/100BASE-TX: half or full;1000BASE-T: full onlySupports a maximum of 24 autosensing10/100 ports24 RJ-45 autosensing 10/100 ports(IEEE 802.3 Type 10BASE-T, IEEE 802.3uType 100BASE-TX); Duplex: half or full2 RJ-45 autosensing 10/100/1000 ports(IEEE 802.3 Type 10BASE-T, IEEE 802.3uType 100BASE-TX, IEEE 802.3abType 1000BASE-T); Duplex:10BASE-T/100BASE-TX: half or full;1000BASE-T: full onlySupports a maximum of 24 autosensing10/100 ports plus 2 autosensing10/100/1000 portsPhysical characteristicsWeight13.23(w) x 6.65(d) x 1.73(h) in(33.6 x 16.89 x 4.39 cm) (1U height)2.98 lb (1.35 kg)17.32(w) x 6.81(d) x 1.73(h) in(44 x 17.3 x 4.4 cm) (1U height)4.41 lb (2.0 kg)13.23(w) x 6.65(d) x 1.73(h) in(33.6 x 16.89 x 4.39 cm) (1U height)2.98 lb (1.35 kg)Memory and processor16 Kb EEPROM; packet buffer size: 2 Mb8kb EEPROM; packet buffer size: 2 Mb 2 Kb EEPROM; packet buffer size: 2.5 MbMounting Mounts in an EIA standard 19-inch telcorack (hardware included); wall, desktopand under-table mountingMounts in an EIA standard 19-inchtelco rack (hardware included); desktopmountingMounts in an EIA standard 19-inch telcorack (hardware included); wall, desktopand under-table mountingPerformance100 Mb Latency1000 Mb LatencyThroughputSwitching capacityMAC address table size< 11 µs (LIFO 64-byte packets)up to 3.5 million pps (64-byte packets)4.8 Gb/s8192 entries< 11 µs (LIFO 64-byte packets)3.5 million pps (64-byte packets)4.8 Gb/s8192 entries< 5.6 µs (LIFO 64-byte packets)< 2.2 µs (LIFO 64-byte packets)up to 6.5 million pps (64-byte packets)8.8 Gb/s8192 entriesEnvironmentOperating temperatureOperating relative humidityNon-operating/Storage temperatureNon-operating/Storage relative humidityAltitudeAcoustic32°F to 104°F (0°C to 40°C) )15% to 95% @ 104°F (40°C), noncondensing-40°F to 158°F (-40°C to 70°C)15% to 90% @ 149°F (65°C), noncondensingup to 10,000 ft (3 km)Power: 0 dB No fan32°F to 104°F (0°C to 40°C)15% to 95% @ 104°F (40°C), noncondensing-40°F to 158°F (-40°C to 70°C)15% to 90% @ 149°F (65°C), noncondensingup to 10,000 ft (3 km)Power: 0 dB No fan32°F to 104°F (0°C to 40°C5% to 95% @ 104°F (40°C), noncondensing-40°F to 158°F (-40°C to 70°C)15% to 90% @ 149°F (65°C), noncondensingup to 16,404 ft (5 km)Power: 0 dB No fanSPECIFICATIONS HPE OfficeConnect 1410-24 Switch(J9663A)HPE OfficeConnect 1410-24-R Switch(JD986B)HPE OfficeConnect 1410-24-2GSwitch (J9664A)Electrical characteristicsFrequencyMaximum heat dissipation VoltageDC voltageCurrentMaximum power rating 50/60 Hz17 BTU/hr (17.93 kJ/hr)100-240 VAC12 V0.4 A4.8 WNotes:Maximum power rating and maximumheat dissipation are the worst-casetheoretical maximum numbers providedfor planning the infrastructure withfully loaded PoE (if equipped), 100%traffic, all ports plugged in, and allmodules populated.The exact input voltage and frequencyrating are determined by the specificpower adaptor part number ordered.Please select the correct power adaptorcountry option.50/60 Hz21 BTU/hr (22 kJ/hr)100-240 VAC3.3 V1.1 A3.6 WNotes:Maximum power rating and maximumheat dissipation are the worst-casetheoretical maximum numbers providedfor planning the infrastructure withfully loaded PoE (if equipped), 100%traffic, all ports plugged in, and allmodules populated.This model provides an internal powersupply. Please select the correct powercord country option.50/60 Hz37 BTU/hr (39.03 kJ/hr)100-240 VAC12 V0.9 A10.8 WNotes:Maximum power rating and maximumheat dissipation are the worst-casetheoretical maximum numbers providedfor planning the infrastructure withfully loaded PoE (if equipped), 100%traffic, all ports plugged in, and allmodules populated.The exact input voltage and frequencyrating are determined by the specificpower adaptor part number ordered.Please select the correct power adaptorcountry option.Safety UL 60950-1; CSA 22.2 60950-1;IEC 60950-1:2005; EN 60950-1:2006 +A11:2009UL 60950-1; CSA 22.2 60950-1;IEC 60950-1:2005; EN 60950-1:2006 +A11:2009UL 60950-1; CSA 22.2 60950-1;IEC 60950-1:2005; EN 60950-1:2006 +A11:2009Emissions FCC Rules Part 15, Subpart B Class A FCC Rules Part 15, Subpart B Class A FCC Rules Part 15, Subpart B Class A ImmunityGenericENESDRadiatedEFT/BurstSurgeConductedPower frequency magnetic field Voltage dips and interruptions HarmonicsFlicker EN 55022 CISPR 22EN 55024, CISPR 24IEC 61000-4-2IEC 61000-4-3IEC 61000-4-4IEC 61000-4-5IEC 61000-4-6IEC 61000-4-8IEC 61000-4-11IEC 61000-3-2IEC 61000-3-3EN 55022 CISPR 22EN 55024, CISPR 24IEC 61000-4-2IEC 61000-4-3IEC 61000-4-4IEC 61000-4-5IEC 61000-4-6IEC 61000-4-8IEC 61000-4-11IEC 61000-3-2IEC 61000-3-3EN 55022 CISPR 22EN 55024, CISPR 24IEC 61000-4-2IEC 61000-4-3IEC 61000-4-4IEC 61000-4-5IEC 61000-4-6IEC 61000-4-8IEC 61000-4-11IEC 61000-3-2IEC 61000-3-3Notes:IEEE 802.3az Energy Efficient Ethernet protocol is supported by the HPE 1410-24G-R (JG708A), HPE 1410-16 (J9662A) and HPE 1410-24 (J9663A) Switches.(CONTINUED)Page 11 Data sheetSPECIFICATIONS HPE OfficeConnect 1410-24 Switch(J9663A)HPE OfficeConnect 1410-24-R Switch(JD986B)HPE OfficeConnect 1410-24-2GSwitch (J9664A)Services Refer to the Hewlett PackardEnterprise website at/networking/services fordetails on the service-level descriptionsand product numbers. For details aboutservices and response times in your area,please contact your local Hewlett PackardEnterprise sales office.Refer to the Hewlett PackardEnterprise website at/networking/services fordetails on the service-level descriptionsand product numbers. For details aboutservices and response times in your area,please contact your local Hewlett PackardEnterprise sales office.Refer to the Hewlett PackardEnterprise website at/networking/services fordetails on the service-level descriptionsand product numbers. For details aboutservices and response times in your area,please contact your local Hewlett PackardEnterprise sales office.Standards and Protocols (applies to all products in series)General protocols IEEE 802.1p Priority IEEE 802.3ab 1000BASE-T GigabitEthernet over twisted pair (10/100/1000models only)IEEE 802.3i 10BASE-T Ethernet overtwisted pair IEEE 802.3u 100BASE-TX Fast Ethernet, 100BASE-FX with auto negotiation IEEE 802.3x Flow Control(CONTINUED)Rate this documentSign up for updates Data sheetHPE 1410 Switch Series accessoriesCablesHPE 0.5 m Multimode OM3 LC/LC Optical Cable (AJ833A) HPE 1 m Multimode OM3 LC/LC Optical Cable (AJ834A) HPE 2 m Multimode OM3 LC/LC Optical Cable (AJ835A) HPE 5 m Multimode OM3 LC/LC Optical Cable (AJ836A) HPE 15 m Multimode OM3 LC/LC Optical Cable (AJ837A) HPE 30 m Multimode OM3 LC/LC Optical Cable (AJ838A) HPE 50 m Multimode OM3 LC/LC Optical Cable (AJ839A)HPE Premier Flex LC/LC Multi-mode OM4 2 fiber 1m Cable (QK732A) HPE Premier Flex LC/LC Multi-mode OM4 2 fiber 2m Cable (QK733A) HPE Premier Flex LC/LC Multi-mode OM4 2 fiber 5m Cable (QK734A) HPE Premier Flex LC/LC Multi-mode OM4 2 fiber 15m Cable (QK735A) HPE Premier Flex LC/LC Multi-mode OM4 2 fiber 30m Cable (QK736A)HPE Premier Flex LC/LC Multi-mode OM4 2 fiber 50m Cable (QK737A)HPE 1410-24G Switch (J9561A)HPE X121 1G SFP LC SX Transceiver (J4858C) HPE X121 1G SFP LC LX Transceiver (J4859C)HPE X111 100M SFP LC FX Transceiver (J9054C)Learn more at/networking© Copyright 2010-2011, 2013-2015, 2016 Hewlett Packard Enterprise Development LP. The information contained herein is subject to change without notice. The only warranties for Hewlett Packard Enterprise products and services are set forth in the express warranty statements accompanying such products and services. Nothing herein should be construed as constituting an additional warranty. Hewlett Packard Enterprise shall not be liable for technical or editorial errors or omissions contained herein.4AA1-1585ENW, April 2016, Rev. 7。
爱丁堡仪器FLS980光致发光光谱仪用户手册说明书
Photoluminescence Spectrometer (FLS980)Instrument Summary:The Edinburgh Instruments’ FLS980 photoluminescence spectrometer offers both steady state and time resolved (lifetime) fluorescence spectroscopy measurements of solid and liquid samples. The instrument is equipped with four tunable, pulsed repetition rate lasers (wavelengths including: 315, 375, 635, and 980 nm), a flashlamp, and a xenon arc lamp. The FLS980 incorporates two silicon detectors (200-1100 nm) and an InGaAs detector. By combining time correlated single photon counting (TCSPC) and multi-channel scaling (MCS) the FLS980 excels in fluorescence lifetime measurements which span 12 orders of magnitude, ranging from picoseconds to seconds.Figure 1. The Edinburgh Instruments FLS980, photoluminescence spectrometer.Safety and Precautions:∙Startup: If you are the first user of the day, turn on the FLS980 and let it run for 20 min.∙Shutdown:Turn off the lamp’s and instrument if you are the last user for the day.∙Warning: Avoid running a steady-state excitation or emission scan in which λEx= λEm.∙Warning: Check the compatibility of liquid samples with your cuvettes. Plastic cuvettes (Ex: Polystyrene) can absorb organic liquids (Ex: Toluene) and can leak in the instrument.∙Check:If you do not get signal, check the beam dump to ensure the instrument is configured properly. Additionally, check to make sure there are no optical filters.I. Experiment Planning:1.Determine the Approximate Fluorescence Profiles of your Sample –It is useful to havea basic understanding of the excitation and emission wavelengths of your sample beforestarting an experiment. If the sample has unknown fluorescence properties you can runa signal probing experiment to determine approximate values for excitation and emission.See the “Analysis of Unknown Samples” section below.2.Steady-State Measurement – After determining the approximate excitation and emissionvalues you will want to run a “Steady-State Excitation Scan” and a “Steady-State Emission Scan” to more accurately determine the fluorescence properties of your sample.3.Lifetime Measurement – After determining the steady-state properties of your sample,you are ready to measure the “Fluorescence Lifetime” using either a pulsed LED laser or the flash lamp.II. Start the FLS980:1.Turn on the Instrument –Flip the “PH1” toggle switch behind the computer monitor.2.Turn on the Fan –Flip the “CO1” toggle switch located behind the monitor.3.Turn on Xe Lamp – Flip the lower toggle switch located on the back of the Xe lamp.4.Instrument Stabilization– Allow the instrument to stabilize for 20 minutes.5.Ignite the Xe Lamp– Press and hold the silver button located on top of the instrument.6.Open the Software – Open the Desktop (Password:RandLab). Click the “F980” Icon. III. Insert a Sample:1.Open the Chamber– Lift the circular lid off the top of the FLS980.2.Check Instrument Configuration – Ensure that the beam dump is oriented in the correctposition and that no glass filters are inserted in the path of the beam.3.Insert the Sample in the Holder –The FLS980 can be configured to accommodatecuvettes and films. The mounts are kept in the sample chamber or in the drawers beneath the instrument.*Cuvette Note 1: For liquid samples it is best to utilize dilute concentrations. Samples with high concentrations can limit penetration of the beam through the cuvette. This “inner filter effect” will hurt accuracy of excitation scans. Check to make sure the beam fully penetrates through the liquid.*Cuvette Note 2: Check the compatibility of liquid samples with your cuvettes. Plastic cuvettes (Ex: Polystyrene) can absorb organic liquids and could leak in the instrument.4.Close the Chamber – Replace the lid on the FLS980, this compresses the interlock.5.Position the Sample to Maximize Signal– The sample can be oriented back and forth tomaximize signal by turning the black knob located on the front of the instrument. Check the counts detected in the “Signal Rate Window”.IV. Analysis of Unknown Samples:*Note: For unknown samples it is useful to do a manual excitation and emission scan using the signal rate window. This will provide approximate excitation and emission values prior to running more accurate steady-state excitation and emission scans.1.Open the Signal Rate Window –The “Signal Rate Window” lists live counts as recordedwithin the instrument and can be used to optimize signal parameters (See Figure 2).2.Set the Bandwidth (Δλ) to~0.1–The bandwidth governs the amount variation inwavelength. By setting a low value for unknown samples we prevent detector saturation.3.Set the Step Sizes to ~5 nm – The step size controls the step size taken when scanningthe spectrum. By setting a large step size we can quickly assess the sample.4.Set the Excitation and Emission Wavelengths –Set λEx to ~300 nm and λEm to ~400 nm.5.Manually Increase the Excitation λ–Press the arrow key to iteratively increase theexcitation λ by 5 nm. Monitor the emission signal; look for an increase in CPS. If no signal is detected in this range, increase λEx to ~400 nm and λEm to ~500 nm and continue.6.Scan the Emission λ Range –Once the excitation peak is determined, enter this value asthe excitation wavelength. Next iteratively step through the emission spectrum to find the maximum emission λ.7.Record Approximate Excitation and Emission Wavelengths –These values will helpdesign a steady-state fluorescence procedure.8.Adjust Sample Position – Use the translator knob to adjust sample position and maximizesignal.Figure 2. Screenshot of the signal rate window.*Note: During a steady-state emission scan, the excitation λ is held constant and the detector is used to incrementally scan the light emitted by the sample to determine the emission profile.1.Setup the Emission Scan Parameters– Open the signal rate window and set values.o Excitation Wavelength –Enter an excitation wavelength (λEx), this wavelength (constant) should be at a λ which excites the sample and at least 15 nm shorterthan the onset of the emission profile.o Emission Wavelength –Enter the emission wavelength (λEm), this wavelength should correspond approximately with the emission peak.o Enter Step Size and Band Width –A step size of 0.2 nm and a Δλ of 1.0 should work for most samples.o Select a Light Source and Detector– The Xe900 lamp and the PMT detector should work for most samples.2.Click the “Apply” B utton – This stores the settings in the software.3.Check the Signal – The sample should produce a detectable signal that is between 0 and2 million CPS. If the signal is >2 million CPS, reduce the Iris setting from 100% until thesignal drops below 2 million CPS.4.Open the Steady-State Window –Press the λ icon to open the steady-state scan options.o Check the General Tab– For emission scans select the: EmCorr Scan option.o Check the Excitation Tab–The excitation settings should reflect the settings selected in the signal rate window.5.Update the Emission Tab –Update the “Emission Scan Parameters” options at the bottomof the window.o Scan Range – The scan should begin at a wavelength that is at least 15 nm greater than the λEx value (i.e.λEm Start= λEx + 15 nm) and end at a final value that is ~200nm greater than the starting wavelength (i.e.λEm Stop= λEm Start + 200 nm).o Step – 1.00 nm is a standard step size.o Dwell Time – 0.2 Seconds.o Number of Scans – 5 Scans (this will average data collection over 5 runs).6.Insert a Filter –Add an appropriate high-pass filter that is betweenλEx and λEm Start.o Check for and remove any previous filters.7.Press Start to begin the Scan –The experiment can be aborted by hitting the stop sign.Figure 3. Emission Scan Setup Window.*Note: During a steady-state excitation scan, a constant emission wavelength is monitored to determine CPS produced as the excitation wavelength is varied (See Figure 4).1.Setup the Excitation Scan Parameters– Open the signal rate window and set values.o Excitation Wavelength –Enter an excitation wavelength (λEx), this wavelength should correspond approximately with the excitation peak.o Emission Wavelength –Enter the emission wavelength (λEm), this λshould correspond to a value that is longer than the upper limit of the excitation range.o Enter Step Size and Band Width –A step size of 0.2 nm and a Δλ of 1.0 should work for most samples.o Select a Light Source and Detector – The Xe900 lamp and the PMT detector should work for most samples.2.Click the “Apply” Button – This stores the settings in the software.3.Check the Signal – The sample should produce a detectable signal that is between 0 and2 million CPS. If the signal is >2 million CPS, reduce the Iris setting from 100% until thesignal drops below 2 million CPS.4.Open the Steady-State Window –Press the λ icon to open the steady-state scan options.o Check the General Tab– For excitation scans select: Recording Ref Data.o Check the Emission Tab–The emission settings should reflect the settings selected in the signal rate window.5.Update the Excitation Tab –Update the “E xcitation Scan Parameters” options at thebottom of the window.o Scan Range – The scan should end at a wavelength that is at least ~15 nm less than the emission wavelength value (i.e.λEx Stop= λEm - 15 nm) and start at a value thatis ~200 nm less than the emission wavelength (i.e.λEx Start= λEm - 200 nm).o Step – 1.00 nm is a standard step size.o Dwell Time – 0.2 Seconds.o Number of Scans – 5 Scans (this will average data collection over 5 runs).6.Insert a Filter –Add an appropriate high-pass filter that is betweenλEm and λEx Stop.o Check for and remove any previous filters.7.Press Start to begin the Scan –The experiment can be aborted by hitting the stop sign.Figure 4. Excitation Scan Setup Window.VII. Lifetime Scan:*Note: A lifetime scan can be performed after obtaining the steady-state excitation and emission profile of a sample.1.Configure the Instrument for Lifetime Measurements– Flip the beam dump over to blockthe Xe lamp. Rotate the sample holder 90 ° to face the LED laser source.2.Choose an Appropriate Light Source– Review the excitation and emission data, select alaser closest to the excitation peak of your sample. A range of pulsed LED lasers are available with wavelengths including: 315, 375, 635, and 980 nm. Additionally, a flashlamp is available for samples with long lifetimes.3.Mount the Light Source – Loosen the knob under the current LED source and slide theprevious LED off of the mount. Cap the LED using a red LED end cap. Unplug the red and black cords from the previous LED and connect with the appropriate LED laser. Slide the new LED on the mount and retighten the knob under the LED.4.Turn the LED On – Turn the key on the back of the LED. Wait for the blinking light to stopblinking and stay lit. Then press the red button.5.Select a Repetition Rate – Turn the dial on the LED to a desired repetition rate. This rateshould be long enough to capture the full lifetime of the sample, yet short enough to efficiently collect and bin the data.6.Open the Signal Rate Window – Change the source to the TCSPC Laser. Increase ΔλEm to~5.00 nm. Ensure that the Emission signal is < 2% of the TCSPC’s excitation value. Rotate the optical power knob on the LED to reduce the excitation signal if necessary.7.Open the Lifetime Window– Press the τ icon and select “New Lifetime”.8.Edit Lifetime Settings:o Time Range– This setting should roughly match value selected on the LED dial.o Channels– Set the number of channels (~2048) that you would like to bin data in.Higher values give better resolution but divides counts across more bins.o Stop Condition– Set the Peak counts to value ~2000 counts.9.Press Start – The experiment can take several minutes to hours.10.Check Data– The data should present a peak with a gradually sloping tail. If the data isbinned in such that a series of horizontal lines begin to form, then it is likely that the repetition rate is too high. If this is the case, adjust the knob on the LED and update the Time range setting in the software.*Note: For samples which have extremely fast lifetimes, it may be necessary to deconvolve the instrument’s response function (IRF) from the data. If this is the case, select the “IRF”setting and first run an IRF scan before analyzing your sample.VIII. Data Analysis:bining Spectra–Click the “Join Visible” button at the top of the software. This willcreate a new window that plots multiple spectra on the same graph for comparison.2.Normalizing Data – Data is often normalized for presentation. To normalize data, click“Data”, “Normalize”, select the desired file, and enter a normalized value (Ex: 1.0).3.Data Fitting–Select “Analysis” → “Ex. Tail Fit” → estimate a value for τ1 and select the“Time Resolved Emission Scan (TRES)” option. Alter the τ1 value if it fits the data poorly.4.Saving Data–Export data by selecting “File” and “Export Data to ASCII”.IX. Instrument Shutdown:1.Remove Samples from the Instrument–Remove samples and clean up the instrument.2.Remove Filters from the Instrument – This helps the next user.3.Turn off the Lamp– If you are the last user of the day, turn off the Xe lamp. Allow ~15minutes for the lamp to cool down before powering off the cooling unit.4.Turn off the Fan and Main Power Switch– After the lamp has cooled sufficiently, turn offthe remaining toggle switches in the reverse order as that used to turn on the instrument (turn off CO1 followed by PH1).5.Sign the Log Book.6.Log Off of the Instrument.Emergency Information:Medical Emergencies: Contact 911 and Public Safety (609) 258-1000Room / facility emergencies: Contact Public Safety (609) 258-1000Issues related to the instrument:1. Contact IAC Staff.2.If unsure, leave system as is.3. Try to power down the system.Audible/Siren Emergency Alerts:Follow previous steps 2 & 3 and leave the building.Emergency Contact Information:Nan Yao: Office (609) 258-6394; Cell (908) 922-2236 Email: ******************John Schreiber: Office (609) 258-0034; Cell (215) 431-4670 Email: ******************Paul Shao: Office (609) 258-3851; Cell (847) 721-086 Email: *******************Daniel Gregory: Office (609) 258-7956; Cell (302) 542-3182 Email: ****************************Yao-Wen Yeh: Office (609) 258-7956; Cell (848) 248-8058 Email: ******************。
电子辐照对IGBT关断和通态特性的影响
图 3 对应不同 Ic 的关断过程曲线 (a) Ic = 12A (b) Ic = 5. 7A ( X : t = 2μs/ 格 , Y: V ceo = 100V/ 格 ; V G = 2V/ 格 ; Ic = 2A/ 格)
© 1995-2006 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved.
照前的 30μs 降到 4μs 左右 。
图 5 pin 二极管载流子寿命随 φ的变化
图 6 电子辐照前后的 IGB T 关断波形 (辐照能量 :12MeV ,剂量 :6 ×10 - 12)
(a) 电子辐照前 ( X : t = 10μs/ 格 , Y: V ceo = 10V/ 格 ; Ic = 0. 5A/ 格)
(8)
图 6 示出电子辐照前后的 I GB T 关断波
形 。图 6 表明 ,辐照后的 I GB T 关断时间从辐
© 1995-2006 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved.
96
《电力电子技术》1997 年第 2 期 1997. 5
电子辐照对 IGB T 关断和通态特性的影响
95
分析研究认为[1 ] ,这是因为随着 I GB T 的 Ic 增大 ,关断时快速下降部分的电流亦增大 , 而指数衰减部分的关断电流并未增大的原因 。 为了证明这一观点 ,将分离 MOSFET 和双极 晶体管按图 1 所示连接起来 ,加不同的集电极 电压 V c ,观察下降过程的电流波形 ,如图 4 所 示 。由图 4 可见 ,双极晶体管发射极电流波形 中的快速下降部分与 MOSFET 的电流关断波 形相吻合 ,其中 MOSFET 的电流亦为双极晶 体管的基极电流 。从上述试验曲线可以肯定 I GB T 关断电流的快速下降部分对应于 I GB T 中 MOS 沟道电流在关断时的迅速消失 。
晶体硅硅片、规定以及工艺过程中lifetime测试技术
7
Carrier Recombination Lifetime: 0.1 to 10,000 μs
Bulk material Cells and Passivated wafers as-cut wafers
0.01 0.1 1 10 100 1000 10000 100000
Carrier Recombination Lifetime (μ s)
生活中不可或缺的科技产品英语作文
科技之光：生活中不可或缺的科技产品In today's world, technology is an integral part of our daily lives. It has become so pervasive that we often take it for granted, yet its absence would leave us feeling lost and disconnected. From the moment we wake up to the moment we fall asleep, we interact with various technological devices that make our lives easier, more convenient, and more entertaining.One of the most essential technology products in our lives is the smartphone. It has revolutionized the way we communicate, access information, and stay entertained. With a smartphone, we can make calls, send messages, browse the internet, take photos and videos, play games, and listen to music, all in the palm of our hands. The smartphone has also transformed the way we work, as it allows us to be productive even when we're not in the office.Another indispensable technology product is the computer. Whether it's a laptop, desktop, or tablet, the computer has become a vital tool for work, education, and entertainment. It enables us to perform complex tasks efficiently, such as data analysis, graphic design, andvideo editing. The computer also provides a platform for learning, as it gives us access to vast amounts of information and resources. In addition, it's a great toolfor relaxation, as we can watch movies, play games, or socialize with friends and family online.Moreover, the internet has become an indispensable part of our lives. It has connected us to the world, allowing us to stay up-to-date with news and events, and to communicate with people from all over the globe. The internet has also transformed the way we shop, as it gives us access to awide range of products and services from the convenience of our own homes.Technology has also made our homes smarter and more efficient. Smart home devices such as thermostats, lightbulbs, and security systems allow us to control our homes remotely, saving us time and energy. These devicescan be integrated into our smartphones or computers, making it easy to manage our homes even when we're not at home.In conclusion, technology products such as smartphones, computers, the internet, and smart home devices have become indispensable in our lives. They have made our lives easier,more convenient, and more entertaining. As technology continues to evolve and improve, we can expect thesedevices to become even more essential to our daily lives.**科技之光：生活中不可或缺的科技产品**在当今世界，科技已经成为我们日常生活中不可或缺的一部分。
生在一个高科技产品的时间英语作文
生在一个高科技产品的时间英语作文全文共3篇示例，供读者参考篇1Living in a time of high-tech productsIn today's society, we are fortunate to live in a time when technology is advancing at an unprecedented rate. High-tech products have become an integral part of our daily lives, making tasks easier, communication faster, and entertainment more convenient. From smartphones and smart home devices to artificial intelligence and virtual reality, the impact of high-tech products on our lives is undeniable.One of the most common high-tech products that we rely on every day is our smartphones. These devices have evolved from simple communication tools to powerful computers that can perform a myriad of functions. We use our smartphones to make calls, send messages, check emails, browse the internet, take photos, listen to music, and even pay for goods and services. The convenience and versatility of smartphones have made them indispensable in our lives.Another high-tech product that has revolutionized the way we live is artificial intelligence. AI technology is used in a wide range of applications, from virtual assistants like Siri and Alexa to self-driving cars and automated customer service systems. AI has the potential to enhance efficiency, improve productivity, and create new opportunities in various industries. As AI continues to advance, we can expect to see even greater innovation and integration into our daily lives.Virtual reality is another high-tech product that is quickly gaining popularity. VR headsets allow users to immerse themselves in virtual worlds and experiences, such as gaming, entertainment, education, and training. The realistic simulations and interactive environments provided by VR technology have the potential to revolutionize entertainment and communication in the future. As VR technology becomes more affordable and accessible, we can expect to see a wider range of applications and opportunities for users.As we embrace high-tech products in our daily lives, it is important to consider the implications and challenges that come with them. Privacy and security concerns are major issues with the increasing use of technology, as our personal information and data are vulnerable to hacking and misuse. Additionally, therapid pace of technological advancement can lead to job displacement and inequality, as certain industries become obsolete and others require specialized skills to operate.Despite these challenges, high-tech products have the potential to improve our lives in countless ways. They have revolutionized communication, entertainment, healthcare, education, transportation, and many other aspects of society. As we continue to innovate and develop new technologies, it is important to prioritize ethical considerations, regulations, and responsible use to ensure that high-tech products benefit humanity as a whole.In conclusion, living in a time of high-tech products presents us with endless opportunities and challenges. From smartphones and artificial intelligence to virtual reality and beyond, technology has the power to shape our future and transform the way we live, work, and interact with the world. By embracing innovation, balancing risks and rewards, and fostering a culture of responsible technology use, we can fully realize the potential of high-tech products in our lives.篇2Living in a time of advanced technology means that our daily lives are constantly influenced and shaped by the latest innovations. From smartphones and social media to self-driving cars and artificial intelligence, we are surrounded by high-tech products that have changed the way we communicate, work, and live. In this essay, I will explore the impact of being born in a time where technology plays a crucial role in our daily lives.One of the most obvious benefits of living in a time ofhigh-tech products is the convenience and efficiency they bring to our lives. For example, smartphones have revolutionized the way we communicate by allowing us to stay connected with others no matter where they are in the world. Social media platforms like Facebook and Instagram have made it easier for us to share our lives with others and stay in touch with friends and family. Additionally, online shopping has made it possible for us to buy almost anything we want with just a few clicks, saving us time and effort.Furthermore, high-tech products have also improved our work efficiency and productivity. With the help of computers and software programs, tasks that used to take hours can now be completed in minutes. Businesses can now reach a wider audience through digital marketing and online advertising,increasing their revenue and expanding their customer base. Additionally, the rise of telecommuting and remote work has allowed employees to work from anywhere in the world, contributing to a better work-life balance.On the other hand, there are also challenges that come with living in a time of high-tech products. For example, the constant bombardment of information and notifications from our devices can be overwhelming and distracting. Many people find it hard to disconnect from technology, leading to issues like digital addiction and decreased face-to-face interactions. Moreover, the rapid pace of technological advancements means that some people may struggle to keep up with the latest trends and developments, leading to a digital divide between those who have access to technology and those who do not.In conclusion, being born in a time of high-tech products has its pros and cons. While technology has undoubtedly improved our lives in many ways, it is important to be mindful of the impact it has on our mental health, relationships, and society as a whole. By striking a balance between embracing technology and disconnecting from it when needed, we can fully enjoy the benefits of living in a time of advanced technology.篇3Living in a time of high-tech productsIn today's fast-paced world, we are fortunate to be living in a time where high-tech products are becoming more and more prevalent. From smartphones and tablets to smart home devices and virtual reality headsets, technology has revolutionized the way we live, work, and interact with one another. In this essay, we will explore the impact of high-tech products on our daily lives and how they have changed the way we navigate the world.One of the most noticeable ways in which high-tech products have transformed our lives is through communication. With the advent of smartphones and social media platforms, we are now able to connect with people from all around the world instantly. No longer do we have to rely on traditional means of communication such as letters or phone calls – we can simply send a message or make a video call with the touch of a button. This has made our world feel smaller and more interconnected, allowing us to build relationships and stay in touch with friends and family regardless of distance.In addition to communication, high-tech products have also revolutionized the way we work. With the rise of remote work and digital nomadism, many people are now able to work from anywhere in the world as long as they have an internetconnection. This has opened up new opportunities for flexibility and autonomy in the workplace, allowing individuals to pursue their passions and maintain a healthy work-life balance. Furthermore, high-tech products such as productivity apps and project management tools have made it easier than ever to collaborate with colleagues and stay on top of tasks, boosting efficiency and productivity in the workplace.Moreover, high-tech products have also had a profound impact on entertainment and leisure. With streaming services like Netflix and Spotify, we have access to a vast array of movies, TV shows, music, and podcasts at our fingertips. Virtual reality headsets have taken gaming to new heights, immersing players in realistic and interactive worlds. Smart home devices such as smart speakers and smart thermostats have made our living spaces more convenient and efficient, allowing us to control our homes with simple voice commands. These innovations have transformed the way we relax and unwind, providing endless possibilities for entertainment and enjoyment.Despite the many benefits of high-tech products, there are also challenges and concerns that come with their widespread adoption. Privacy and security have become major issues in the digital age, as our personal information and data are vulnerableto hacking and misuse. The constant bombardment of notifications and information can also lead to information overload and distraction, affecting our ability to focus and be present in the moment. Furthermore, the rapid pace of technological advancements can make it difficult to keep up with the latest trends and updates, leaving some feeling overwhelmed and left behind.In conclusion, living in a time of high-tech products has both positive and negative implications for our daily lives. While these innovations have transformed the way we communicate, work, and entertain ourselves, they also come with challenges related to privacy, security, and information overload. As we navigate this ever-changing technological landscape, it is important to strike a balance between embracing innovation and mindful consumption, ensuring that we harness the power of high-tech products for the betterment of society. Only then can we fully realize the potential of technology to improve our lives and shape a brighter future for generations to come.。
电气连接润滑剂 - 埃克斯特罗利布 用于开关和连接器的专用润滑剂说明书
Electrolube have been the leading supplier of contact lubricants since their invention by the founder in the 1950s. They increase the reliability and lifetime of current carrying metal interfaces, including switches, connectors and busbars.Electrolube has earned an unsurpassed reputation for the manufacture and supply of specialist lubricantsto the automotive, military, aerospace, industrial and domestic switch manufacturing sectors. The range has been developed over the years to accommodate many advances in such rapidly advancing industries; combining excellent electrical properties and lubricity with plastics compatibility.Contact lubricants are specially formulated greases and oils that reduce friction and enhance the electrical performance of current carrying metal interfaces in switches and connectors. Electrolube products are electrically insulative in thick films, preventing tracking in ultra thin films, i.e. between closed metal contacts they allow the current to flow, owing to the ‘Quantum Tunnelling Effect’. They also exhibit a neutral pH thereby avoiding surface corrosion.The effectiveness of even perfectly designed switches can be improved by contact lubricants and, when considered at the design stage, significant production cost savings can be achieved by the use of less expensive plastics and contact metals.Tests have shown that contact lubrication can extend the lifetime of switches by more than 300%, producing excellent performance under all circumstances and preventing the need for expensive maintenance.• Extends the operating life of switches • Improves signal quality• Reduces operating temperature • Controls switch ‘feel’• Prevents contamination • Silicone freeContact Lubricants2Contact technology is constantly developing withnew alloys, plastics and customer demands. However, it is still impossible to solve the main cause of switch malfunction i.e. the inability to produce a perfectly smooth metal contact surface.As no metal interfaces are entirely even and smooth, when applied to such surfaces in thin films contact lubricants fill in all surface imperfections, in turn improving contact and electrical performance as well as prolonging the contact life by reducing hot spots, frettage and arcing.By filling in the air gaps between the contacts, contact lubricants dramatically increase the effective surface area, in turn preventing arcing and the related temperature rise and oxide formation. They also provide a barrier to airborne contamination and reduce the effects of friction by facilitating smooth movement.In addition, the use of contact lubricants are typically evaluated for their ‘feel’ characteristics, improving the quality of movement of a switch or in simple plastic/ plastic contacts, for example.Heat GenerationIf there is insufficient surface contact, the current is only carried by a fraction of the ‘designed surface area’ and the heat generated will be concentrated at the contact points. This, in turn, causes the formation of high resistance oxide layers and ‘hot spots’ are observed. The overall efficiency of the switch will be reduced and can eventually lead to complete failureas the two surfaces weld togetherArcing (mini-lightning strikes)This can also occur with un-lubricated contacts; ionisation of the air and the associated rise in temperature causes metal transfer between the contacts, resulting in new ‘peaks and troughs’on the surfaces.Mechanical WearMetal interfaces, whether static or moving, suffer from mechanical wear. In the case of static contacts, thisis called ‘frettage’; the small movements of contacts caused by vibration, temperature changes, etc. Asthe surfaces fret, friction causes metal particles tobe removed from the peaks, breaking through plated surfaces. This exposes surface and underlying metal to the effects of oxidation and wear. Additionally the detached metal particles can cause intermittent signal transmission and ultimately switch failure.Silicone ContaminationAs silicones can “creep” great distances, these products should not be used in switch assembly areas. When silicone is present between moving or vibrating contacts, they react under arcing conditions to form silicon carbide. These crystals abrade the contact surface and cause electrical breakdown. Electrolube contact lubricants also eliminate the problems associated with silicone contamination, providing they are applied prior to the introduction of silicone. Switch OperationThe way a switch ‘feels’ when operated has becomean indicator of quality, particularly within the automotive industry. Contact lubricants, in addition to their technical benefits, can also determine the ‘feel’ of a switch, whether it be strong and decisive for the dashboard of a commercial vehicle, or smooth and quiet for a luxury car.How Contact Lubricants Work3Electrolube’s automotive lubricant product range helps engineers meet the huge demands they face on a daily basis. Design engineers are under pressure to keep costs down by the correct selection of materials for complex, innovative designs.The development of Electrolube’s lubricants, together with leading automotive manufacturers, has led to materials with enhanced performance across widetemperature ranges, improved resistance to the external environment and overall development of the electrical and mechanical properties of these materials. Inaddition, Electrolube lubricants are compatible with the most sensitive of plastics and are continually reviewed to meet the latest regulatory requirements.The most important role of lubricating greases is to protect from wear and corrosion. Damping lubricants are materials which ergonomically control free motion and noise in mechanical components whilst giving a “quality feel” to hand operated mechanisms. For current carrying metal interfaces, the major advantage is that they increase the reliability and lifetime of these components by preventing corrosion and wear, which could include sensors, switches, potentiometers and connectors, for example.The following information covers each of theseapplications in more detail and provides some starting suggestions for choice of lubricants. Technical data sheets can be referred to for additional information on each product and in all applications the lubricant must be fully tested in representative end-use conditions to confirm correct selection.ConnectorsContact lubricants are used extensively for connectors. Connectors in early automotive applications were plagued with “fretting corrosion” problems. Although tin and silver plated contacts are more commonly used, gold plated contacts are also apparent in some connector designs. Gold is a soft material and can exaggerate fretting corrosion.A lubricated switch is subject to far less mechanical wear as the lubricant facilitates smooth movement. Friction and wear are therefore greatly reduced,extending switch lifetime, improving electrical efficiency and allowing the use of a wider selection of materials.Such improvements are extremely important in the challenge of meeting the energy efficiency requirements of today’s more fuel economical and hybrid/electric vehicles.Example ApplicationsG old Plated Contacts/Air-Bag Connectors CG60/SOK High Insertion Force Applications EGFS lip Ring Devices SOB/CO70Dual Purpose LubricationAutomotive Applications4Switches and ContactsHigh Current Arcing Switches or ContactsAs un-lubricated contacts open and close, arcing (mini lightning strikes) can often occur. Ionisation of the air and the associated rise in temperature causes metal transfer between the contacts, resulting in the formation of new ‘peaks and troughs’ – a common problem found in high power contacts. The problem of arcingis also compounded in ‘make and break’ switches, where every time the circuit is opened, the contacts may bounce several times before finally mating. This exacerbates the problems discussed previously and subjects the circuit to repeated surges of current giving a poor signal to noise ratio.This problem is not found in lubricated switches, asthe lubricant fills the air gap between the contacts, preventing arcing, related temperature rises and corrosive chemical formation; as air is excluded from the metal surfaces, airborne contamination cannot form insulative barriers on the metals. Finally, contact lubricants provide a cushion between the contactsto dampen the effects of bouncing.Example ApplicationsS tarters/Ignition CG53A H eating and Ventilation C G71/SOK Medium Current Switches or ContactsThese types of switches vary in design parameters and materials usually employed. Typically more sensitiveplastics and elastomers are used and therefore compatibility with all lubricant materials must be tested.In such applications lubricants are used to dramatically increase the effective surface area of the contact, thus eliminating hot spots, improving efficiency and ensuringthat contact resistance remains low and stable.Example ApplicationsW indscreen Wipers CG71C entral Locking Switches CG60/CG71P ower Seat Switches CG60/CTG/EGF Dashboard Control Mechanisms CG70P ower Window Switches CG70/CG53AM icro Switches EML/CO70/SONLow Current Carrying Switches and ContactsLow current carrying switches and contacts are typically made with the most sensitive plastic and elastomer rubbers, yet being low current carrying, demand thebest electrical performance from contact lubricants. Electrolube’s contact lubricants have been used extensively for high quality audio applications and ergonomic controls. The application of lubricantsprevents corrosion of the metal interfaces, whilstproviding the switch with low levels of electrical noiseand a very stable signal.Example ApplicationsSteering Wheel Switches CG71Light Switches LCGL ow Contact Pressure Switches SOA/CO70/SGNA udio Switches CG71/LCG5Sensors and Non-ElectricalSensors and PotentiometersPotentiometers have low contact forces and must stay in contact with the resistor; a high viscosity grease would not allow close contact with the resistor, therefore the most suitable materials are constructed from low viscosity base oils, coupled with an effective, non-carbonising thickener.As well as functioning at very high temperatures, fluorinated lubricants have exceptional plastics compatibility and solvent resistance and are therefore ideal for fuel level sensors, particularly in oil form where a thin, uniform application of a long lasting lubricant can be applied to the surface.Example ApplicationsFuel Level Sensors EOF/DOF Seat Position EGF/CG60 Electronic Throttle EGF/EOF Interior Components – Non ElectricalInterior components requiring lubrication come in many combinations:• M etal-metal contacts – seating tracks,sunroof tracks, etc.• P lastic-plastic contacts – windscreen wiper gears, window visor, cup holders, grip handles, etc.• P lastic-metal contacts – cables, glove compartment locking mechanisms, etc.Each application requires a certain grease characteristic to provide damping of free movement and noise as well as providing a quality feel. Electrolube’s damping lubricants offer engineers an economical route to quality. Example ApplicationsMedium-Heavy Viscosity:Dashboard Needle Gauge SPG/SCO Window Visor SPGA Window Tracks CTG/SGN Light Viscosity:Cup Holders, Ashtrays, Grip Handles SPG Ventilation Air Flaps SPG/SCO Sunroof Mechanisms SPG/SGN Mirror Adjustments SPG/SCO6It is important to discuss the options available at the design stage to ensure correct product selection and application. Many factors must be considered when choosing a contact lubricant, among the areas to be considered are; voltage, current, operating temperature range, environmental conditions, contact metals, number of cycles and associated plastics.Plastic test bars were coated in various Electrolube lubricants and placed on a test rig under strain. The samples were then conditioned for 7 days at 40ºC before inspectionKey1. Fail – snapped2. Severe stress cracking but not snapped3. Stress cracking seen4. Pass – some very slight stress cracking5. Pass – no incompatibility seenPlastics CompatibilityProduct SelectionABS = Acrylonitrile butadiene styrene PA = Polyamide PBT = Polybutylene terephthalate PC = Polycarbonate PET = Polyethylene terephthalate PP = Polypropylene7Electrolube have a custom built switch rig for the lifetime testing of contact lubricants. Every product is subjected to this test, using a standard automotive switch for comparison purposes.The results provide a measurement of mV drop over the cycling period and show how the use of contact lubricants can dramatically increase switch performance and lifetime.Electrical Testing10 10010 20010 30010 40010UN-LUBRICATED SWITCH CTG CG71 SGA14012010080604020NUMBER OF CyCLESm V D R O P8To establish the consistency and possible variations in performance at a range of temperatures, the cone penetration values were measured according to ASTM D217.The un-worked cone penetrations of various Electrolube contact lubricants were tested at -40ºC, 20ºC and 40ºC:Cone Penetrations-40 20 40SGA SGB CG53A CG60 CG70 CTG SPG SPGA350300250200150100500TEMPERATURE (ºC)U N -W O R K E D C O N E P E N E T R A T I O N9To establish the mechanical performance of the various contact lubricants, 4-ball wear testing was completed to ASTMD 2596/87. Included in this testing were some lubricants from the general maintenance range where the end application is more mechanical lubrication than electrical contact improvement.The test consists of loading the grease into equipment that has four balls under a defined rotation. A pressure load is introduced onto the balls and the load increased according to a logarithm function.The results are given as a pass value and a wearing value at the pass value. The wearing value is measured in mm and quantifies the amount of wear observed on the balls utilised in the test.The weld point is the end of the test where the wearing of the balls was more than 4mm (the maximumaccording to the methodology). This value is usually only used for indication, the pass and wearing values are the most important for selection purposes.Mechanical Testing0 0.5 1 1.5 2 2.5 3 3.5WEAR RESULT AT 100kgf PRESSURE LOAD (mm)MPG CMO ULL EGF SPGA SPG CG70CG60SGB10A test schedule was constructed in order to establish which products provide the highest level of protection in high humidity and corrosive environments.Steel and copper panels were coated in a variety of Electrolube contact and mechanical lubricant products and subjected to 90% humidity at 35ºC for 3 weeks, followed by 1 week in the salt spray chamber, utilising a 5% salt solution at 35ºC.The conditioned panels were visually inspected and the% corrosion/oxidation present was recorded.The results are comparisons, therefore 100% relates to the highest level of oxidation observed on all test substrates.The protection of gold and silver contacts is also very important. A range of gold and silver plated contacts were coated with various contact and mechanical lubricants and placed into the salt spray chamber for 7 days. The settings were 5% salt solution, 35ºC.The majority of the Electrolube products performed exceptionally well as the gold and silver plated contacts showed no signs of corrosion following the test.The following products provided a very high level of protection for the gold and silver plated contacts; EGF, E3C-CA, CG60, CG70, CG71, CG53A, CTG, SGB.The only product to show signs of corrosion on the gold and silver plated contacts was MPG. This product is therefore not advised for use on gold and silver surfaces, particularly where high levels of humidity or salt spray are present.Chlorine ResistanceThis test was devised to determine which contact lubricant products provide the best protectionagainst oxidative environments. Copper panels were coated in various contact and mechanical lubricants and subjected to 2 months at 35ºC in an oxidative atmosphere containing chlorine.The results showed that E3C-CA gave the bestprotection, followed by CG53A, CG60, CG70 and CTG.Protection in Humid / Corrosive EnvironmentsProtection of Gold and Silver Contacts11The Product RangeCG60 – Contact Grease• E xcellent high performance lubricant • R educes electrical background noise • E xcellent plastics compatibility• C ontains a UV trace to alloweasy inspectionCG70 – Contact Grease• E xceptional performance atlow temperatures• V ery good plastics compatibility • G ood electrical performance• O il version available (CO70)CG71 – Contact Grease• E nhanced electrical properties, gives a consistently low mV drop • H igh level of oxidation stability• L ow wear characteristics• G ood plastics compatibilityCG80 – Contact Grease• E xcellent performance at high temperatures• Good electrical properties• Low evaporation weight loss• C ontains a UV trace to alloweasy inspectionCG52B – Contact Grease• R educes contact resistance• S uitable for both moving and static contacts of all metal types• D eveloped initially for the automotive industry• S uccessful connector lubricantCG53A – Contact Grease• E xcellent electrical properties• G ood plastics compatibility• S uperior protection inharsh environments• W ide operating temperature range SGA – Special Contact Grease• E ffective treatment for all types of contacts • R educes contact resistance and arcing of contacts from small relays to high capacity contactors• W ill not migrate from vertical contactsor surfaces• O il version available (SOA)SGB – 2GX Contact Treatment Grease • H igh quality, non-melting contact grease • H ard consistency version (SGBH)and oil version (SOB) available• R educes contact wear and arcing• G ood plastics compatibilitySOK – 8X Contact Treatment Oil• C ontact oil for switch applications• N on-flammable and silicone free• E xcellent electrical properties• R educes arcing and hencecontact wearSON – 10X Contact Treatment Oil• E xtremely effective at lowoperating temperatures• L ow viscosity oil• G rease version (SGN) available• I deal for low contact pressure applications such as micro switchesCTG – Contact Treatment Grease• E xcellent protection incorrosive environments• W ide operating temperature range• G ood electrical performance• E xcellent plastics compatibility12EGF – Eltinert F Grease• E xcellent chemical resistance• E xceptionally wide operating temperature range• P revents and cures high contact resistance caused by silicone contamination• O il version (EOF) and dilute oilversion (DOF) availableE3C-CA – Electrolytic Cell Connection Compound• F or use on connections and switchesin electrolytic, electro-plating and anodising plants• R educes temperature at contact surfaces • I mproves plant productivity and reliability, thus reducing maintenance costs• S uperior corrosion protectionand oxidation stabilityEPC – Electro-Plating Compound• E specially developed for use on electro-plating and anodising plants• I nhibits against corrosion• I mproves electrical contact on anode and cathode bars, pick-up shoes,rack contacts, busbar joints etc.• F ormulated to assist in the removalof tarnish and corrosionC CS – Contact Cleaning Strips• E asy to use• I mpregnated, mildly abrasive card• C leans, refurbishes and lubricates metal contacts• H igh quality contact lubricant SPG – Special Plastic Grease• S ynthetic grease offering outstanding low temperature performance• E xcellent compatibility with thermoplastics, including ABS and Polycarbonate• E ffective lubrication of plastic-to-plastic and plastic-to-metal contact surfaces • M ore adhesive version available (SPGA)EML – Contact Cleaner Lubricant• C leans and lubricates switches, connectors and slip rings• R emoves dirt and protects fromfurther contamination• R educes contact resistance• C ommonly known as switch cleanerSWC – Non-Flammable SwitchCleaner Lubricant• P rovides protection against arcingand corrosion• N on-flammable, can be used onlive equipment• S afe to use on most plastics• C ontains high quality contact treatment oilULL – Ultralube• T enacious long lasting andnon-staining lubricant• I deal for use on printer mechanisms• C an be used as an edge connector lubricant, particularly for gold contacts • C an be used as a silicone inhibit for relays*Various sizes are available for most products, including bulk.1314within our spectrumUK Headquarters / Manufacturing Ashby Park Coalfield WayAshby de la Zouch Leicestershire LE65 1JRUnited Kingdom T +44 (0)1530 419600 F +44 (0)1530 416640 E info @ A division of H K Wentworth Limited Registered office as aboveRegistered in England No. 368850Certificate No. 32082China Headquarters / Manufacturing Building No2, Mauhwa Industrial Park, Caida 3rd Street, Caiyuan Industrial Zone, Nancai Township, Shunyi District Beijing, 101300Peoples Republic of China T +86 (10) 89475123 F +86 (10) 89475123 E info @ All information is given in good faith but without warranty. Properties are given as a guide only and should not be taken as a specification.ELCAT_CONLUBE_GB/0。
英语作文摆脱电子设备
英语作文摆脱电子设备【中英文实用版】Title: Escaping Electronic DevicesIn this digital era, it has become increasingly difficult to detach ourselves from the clutches of electronic devices.From the moment we wake up until we fall asleep, our lives are dominated by the constant ping of notifications and the allure of social media.However, it is crucial to find a balance and learn to break free from these technological chains.在数字化时代，摆脱电子设备的束缚变得越来越困难。
从早晨醒来直到入睡，我们的生活被不断的消息提醒和社交媒体的诱惑所主宰。
然而，找到平衡并学会摆脱这些技术锁链至关重要。
While electronic devices offer convenience and connectivity, they also rob us of valuable time that could be spent engaging in real-life interactions and pursuing hobbies that nourish our souls.It"s time to press the pause button, take a deep breath, and rediscover the joy of living without the dependency on screens.尽管电子设备带来了便利和联系，但它们也剥夺了我们本可以花在真实人际交往和滋养灵魂的爱好上的宝贵时间。
有关芯片英语作文初中
有关芯片英语作文初中As an AI language model, I am unable to browse the internet or access any specific content from it. However, I can provide you with a sample essay on the topic of "Chips" (芯片) for middle school students. Please find the essay below:Title: The Wonders of Chips。
Introduction:In today's technologically advanced world, chips play a crucial role in various aspects of our lives. From smartphones to computers, and even household appliances, chips have become an essential part of modern technology. In this essay, we will explore the significance of chips and their impact on our daily lives.Body:1. Definition and Types of Chips:Chips, also known as integrated circuits, are small electronic devices made of semiconductor materials.They are classified into two main types: microprocessors and memory chips.Microprocessors are responsible for executing instructions and managing tasks in electronic devices.Memory chips store and retrieve data, allowing devices to remember information.2. Importance of Chips:Chips have revolutionized the world of technology by enabling faster and more efficient processing.They have made electronic devices smaller, lighter, and more powerful, enhancing their portability and functionality.Chips have also contributed to advancements infields like medicine, transportation, and communication.3. Applications of Chips:Smartphones: Chips power the functioning of smartphones, enabling various features such as calling, messaging, internet browsing, and gaming.Computers: Microprocessors and memory chips are the backbone of computers, facilitating multitasking, data storage, and faster processing speeds.Internet of Things (IoT): Chips are embedded in everyday objects, connecting them to the internet and enabling communication and control through smartphones or computers.Medical Devices: Chips are used in medical equipment like pacemakers, MRI machines, and glucose monitors, aiding in diagnosis, treatment, and patient monitoring.Automotive Industry: Chips are essential for the functioning of modern cars, controlling engine performance, safety features, and entertainment systems.Renewable Energy: Chips play a crucial role in solar panels and wind turbines, optimizing energy conversion and storage.4. Advancements in Chip Technology:Moore's Law: Named after Gordon Moore, one of the founders of Intel, this law states that the number of transistors on a chip doubles approximately every two years.This exponential growth has led to the developmentof more powerful and energy-efficient chips.Advancements in chip technology have paved the wayfor artificial intelligence, virtual reality, and augmented reality.Conclusion:Chips have become an integral part of our lives,driving technological advancements and enhancing our daily experiences. From smartphones to computers, and even medical devices and renewable energy systems, the impact of chips is far-reaching. As technology continues to evolve, we can expect even more innovative uses for chips in the future.Note: The word count of this essay is approximately 300 words. To reach your desired word count of 1500 words, you can expand on each section by providing more examples, elaborating on the historical development of chips, discussing the challenges faced in chip manufacturing, or exploring the ethical implications of chip usage.。
为什么离不开电子设备英语作文
为什么离不开电子设备英语作文(中英文实用版)Title: Why We Can"t Live Without Electronic DevicesTitle: 我们为何离不开电子设备In today"s modern world, electronic devices have become an integral part of our lives.From the moment we wake up to the moment we go to bed, we are surrounded by a multitude of devices that have become indispensable.在当今现代社会，电子设备已经成为我们生活不可或缺的一部分。
从我们睁开眼睛到我们上床睡觉，我们周围有许多设备已经变得不可或缺。
The first reason why we can"t live without electronic devices is their ability to keep us connected.In today"s globalized world, staying connected with friends and family is more important than ever.Whether it"s through social media, messaging apps, or video calls, electronic devices allow us to communicate with anyone, anywhere in the world.我们离不开电子设备的首要原因是它们能够让我们保持联系。
在当今全球化的世界中，与朋友和家人保持联系比以往任何时候都更重要。
无论是通过社交媒体、即时通讯应用还是视频通话，电子设备允许我们与世界上任何地方的人进行沟通。
用开路电压法测硅太阳电池中少数载流子寿命
编号
效率/ %
少数载流子寿命/μs
脉冲信号发生器
纳秒激光器
1
9. 2
2
9. 5
19
17
21
12
3
10. 0
4
10. 4
46
43
53
52
5
5. 4
6
7. 0
12
10
14
12
7
10. 9
8
10. 6
43
42
41
39
对比以上的四类电池 ,发现无论是单晶电池还 是多晶电池 ,镀膜前后少数载流子寿命的变化都很 大 ,说明在 PECVD 镀膜过程中 Si H4 和 N H3 反应生 成的 H 原子对硅中的杂质和缺陷起着良好的钝化 作用 ,使电池的少子寿命得到较大的提高 ,从而转换 效率也增加 。其中对于镀膜后的单晶电池 ,少数载 流子寿命值与文献[ 6 ]中报道的结果相接近 。
本文利用两种光源通过 OCVD 方法测量了硅 太阳电池中的少子寿命 ,并分析了两种不同光源对 少子寿命测量结果的影响 。
1 理论
当一束脉冲光照到 n + p 半导体上时 ,在半导体 内将产生大量的光生载流子 ,从 n + 区注入到 p 区的 大量电子形成稳定的过剩少子Δn 。在脉冲光结束 后 ,积累在 p 区的过剩少子如同一个充电电容器 ,在 充电电源撤销后仍储存在电容器中的电荷将使样品 两端仍有电压存在[5 ] 。采用外加示波器 (探头电阻 不低于 10MΩ ,认为太阳电池处于开路状态) 探测太 阳电池上存在的电压 。由于开路状态下样品 p 区电 子只能通过复合来逐渐消失 ,因此 ,样品两端剩余电 压随时间下降的快慢 ,将反映过剩载流子在 p 区复 合的快慢 。通过示波器显示光电压的衰减速率 ,就 可推算出 p 区的少数载流子寿命 。
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Lifetime control in silicon devices by voids induced by He ion implantationV. Raineri, G. Fallica, and S. LibertinoCitation: Journal of Applied Physics 79, 9012 (1996); doi: 10.1063/1.362633View online: /10.1063/1.362633View Table of Contents: /content/aip/journal/jap/79/12?ver=pdfcovPublished by the AIP PublishingArticles you may be interested inGettering of Fe to below 1010 cm−3 in MeV self‐implanted Czochralski and float zone siliconAppl. Phys. Lett. 69, 4203 (1996); 10.1063/1.116986Carrier lifetime and x‐ray imaging correlations of an oxide‐induced stacking fault ring and its gettering behavior in Czochralski siliconAppl. Phys. Lett. 69, 3037 (1996); 10.1063/1.116831Secondary defect dissolution by voids in siliconAppl. Phys. Lett. 69, 1783 (1996); 10.1063/1.117485Effect of rapid thermal annealing on carrier lifetimes of arsenic‐ion‐implanted GaAsAppl. Phys. Lett. 69, 996 (1996); 10.1063/1.117107Diffusion of ion implanted boron in preamorphized siliconAppl. Phys. Lett. 68, 2672 (1996); 10.1063/1.116277Lifetime control in silicon devices by voids induced by He ion implantation V.Raineri a)CNR-IMETEM,Stradale Primosole50,I95121Catania,ItalyG.FallicaCorimme,Stradale Primosole50,I95121Catania,ItalyS.LibertinoDipartimento di Fisica,Corso Italia57,I95129Catania,Italy͑Received5June1995;accepted for publication5March1996͒A method to control carrier lifetime in silicon locally and efficiently is presented.Voids,formed byhigh dose He implants,have been characterized by transmission electron microscopy demonstratingthey are well localized in depth within layers thinner than100nm while their lateral extent is limitedonly by the masking capability during He implantation.Deep level transient spectroscopymeasurements,performed on diodes containing different void densities,revealed the presence oftwo well defined trap levels,independent of void characteristics,at E vϩ0.53for holes and E cϪ0.55for electrons.These characteristics make them ideal for lifetime control in reducing parasitictransistor gain.Gummel plots on transistors have shown that when voids are formed the gaindecreases from1to10Ϫ3.The other transistor characteristics are only slightly influenced by thepresence of voids.©1996American Institute of Physics.͓S0021-8979͑96͒00512-9͔I.INTRODUCTIONSilicon technology is moving to ultra large scale integra-tion͑ULSI͒requiring a higher degree of integration,and to integration in the same chip of devices to date considered incompatible͑for examples power devices in logic circuits, bipolar transistors in complementary metal oxide semicon-ductor integrates͒.This further integration is posing several problems in the design of the circuit structure due to the unintentional introduction of parasitic devices which can re-duce the performance of the whole ually,in the case of parasitic transistors the base is heavily doped to de-crease the injection efficiency,although,the high doping cannot always suppress the transistor gain to the desired value.To reduce the latch up in complementary metal oxide semiconductor͑CMOS͒devices the tub,that is the base in a parasitic transistor,is heavily doped by high energy implants or a trench isolation has to be introduced between two adja-cent tubs.A different way to decrease the transistor gain is to re-duce the diffusion length of carriers in the base by control-ling the lifetime locally.In the past we have reached this task by ion implantation of impurities like Pt or Au and their subsequent diffusion.1–3These impurities are known to in-troduce deep levels that strongly influence the minority car-rier lifetime.In this way,the confinement of the low lifetime region to an area larger than100m in diameter across the entire wafer thickness is possible but the results are not com-patible with very high integration.Although many methods for lifetime control in semiconductor devices have been investigated4,5all of them present a poor control on the re-producibility and on the extension of the influenced region.Here,we present a method to control the lifetime locally, based on the formation of voids in silicon.Recently it has been demonstrated that high dose He implants in silicon causes the formation of voids without introducing any impu-rity or contaminant and that the steps required are fully com-patible with wafer processing.6–9The solid solubility of noble gases in silicon is less than1016/cm3;thus,when their ions are implanted at concentrations exceeding this value, bubbles are formed at a depth range determined by the ion energy and at a concentration depending on the ion dose.10It has been observed in silicon that helium is not stable in the bubbles,but it diffuses through the silicon crystal and evapo-rates from the surface during thermal processes at tempera-tures in the range of300°C–700°C.11This behavior,differ-ent from metals,is related to the high permeability of helium in silicon.When helium evaporates,voids are left in the silicon crystal and they are stable at afixed temperature even after very long annealing times,while their density and di-ameter are only determined by the annealing temperature.9 Because of their ability to trap metal impurities,the use of voids for proximity gettering was suggested.12,13The aim of our work is to demonstrate that voids have the basic fea-tures required for carrier lifetime control.It has been shown by transmission electron microscopy͑TEM͒that voids can be well localized in depth within layers thinner than100nm while their lateral extent is limited only by the masking ca-pability during He implantation.9,13They sit in regions that can be more localized than those obtained by implanted me-tallic impurities.Moreover,we have determined the levels introduced in the silicon band gap by deep level transient spectroscopy͑DLTS͒.Our results are in agreement with val-ues reported in literature.14Indeed,large doses are not nec-essary and cause detrimental related effects,while doses,just enough to form voids after annealing,do not present disad-vantages.We will show that the localization and the charac-teristics of these voids make them ideal for lifetime control in reducing parasitic transistors gain.a͒Electronic mail:Raineri@CT.INFN.ITII.EXPERIMENTTo study the electrical characteristics of voids we formed pϩ–n diodes over an area of3.65mm2in an n-type͑7ϫ1014P/cm3as determined by spreading resistance mea-surements͒epitaxial layer grown on n-type5in.wafer7⍀ϫcm.A polycrystalline silicon layer͑200nm thick͒was deposited on the Si surface and then implanted with40keV BF2ions for a dose of5ϫ1015cm2.A subsequent thermal process performed in a rapid thermal furnace at1000°C for 30s produced the rapid diffusion of boron in the polycrys-talline silicon and its drive-in into silicon forming a pϩ–n junction.The pϩregion extends from the silicon surface to a depth ofϷ0.3m and was only slightly influenced by fur-ther annealing treatments.Next,voids were formed in the diode structure at a depth of1.3m by implanting helium ions at300keV for a dose of5ϫ1016/cm2and performing a rapid thermal anneal at two different temperatures͑800°C and1000°C͒for the same time:5min under N2flow.The diode was directly contacted on the pϩdoped polycrystalline silicon,with the second contact on the back of the wafer.TEM cross-sectional samples were prepared by me-chanical thinning followed by5keV Arϩion milling.TEM analyses were carried out with a Jeol2010FX microscopeworking at200kV in two beam condition with the͑220͒spotexcited.DLTS measurements were carried out by a BioradDL4600apparatus,in capacitance mode with a scan tem-perature from80K to room temperature.The voltage for thefilling pulse wasϩ0.3V.To study the effects of voids with different characteris-tics on the transistor gain,transistors with a low gain werefabricated on4in.wafers.By photolithography,windows of450ϫ450m2were opened on1m thick thermal oxide and then,boron ions were implanted͑80keV6.5ϫ1014/cm2͒through a thin͑50nm͒screen oxide.After the diffusion ofthe base,He ions were implanted at300keV at several doseson a25mm area to form voids at a depth of1.3m.In each wafer two spots with different helium doses͑1ϫ1016and 3ϫ1016/cm2or6ϫ1016/cm2and1ϫ1017/cm2͒were im-planted.In this way three kinds of transistors,the reference and the two with voids in the base,are present in the same wafer,i.e.,subject to exactly the same thermal budget.Fi-nally,the emitter was formed by phosphorus implantation at 80keV1ϫ1016/cm2followed by a diffusion at920°C for30 min in wet͑H2O͒ambient and by the standard Al/Si metal-lization procedure.As already established,voids are stable and remain well localized even after long thermal treatments also at very high temperatures.This allows one to form the voids during any step of the device fabrication,and the se-quence described is not obligatory.III.RESULTS AND DISCUSSIONThe void morphology in the diodes,as obtained by cross sectional TEM analyses,is shown in Figs.1͑a͒and1͑b͒for annealing at800°C and1000°C,respectively.The depth distribution and the void dimensions can be observed in the micrographs.At800°C voids are formed and localized at a depth between 1.0and 1.5m from the polycrystalline silicon–silicon interface.They are small in diameter͑Ͻ0.01m͒and many defects are associated with their presence.At 1000°C͓Fig.1͑b͔͒voids are very visible and confined in a band extending from a depth of1.1to1.3m while their diameter reaches0.04m.Moreover,dislocations joining different voids are visible.These dislocations,always local-ized in the void band,are probably due to the stress induced in the silicon crystal by the presence of voids.Furthermore, we can observe that at the highest temperature,1000°C,the polycrystalline silicon layer results grown epitaxially on the silicon substrate,but in any case we will continue to refer to the polycrystalline silicon–silicon interface.In Fig.2the capacitance͑1/C2͒is plotted versus the reverse voltage for the diodes annealed at800°C͑full squares͒and at1000°C͑full circles͒.Both plots,already nearly straight lines,were linearlyfitted to obtain the experi-mental carrier concentration.It is in agreement,withinthe FIG.1.Cross sections TEM analyses on diodes implanted with300keV, 5ϫ1016He/cm2and annealed for5min at800°C͑a͒and1000°C͑b͒.FIG.2.Capacitance voltage measurements performed on diodes annealed at 800°C͑solid squares͒and1000°C͑solid circles͒.experimental error,with that obtained for the n -type epitaxial layer by independent measurements and reported in the ex-perimental section ͑7ϫ1014at/cm 3͒.In the case of the sample annealed at the lower temperature,a deviation from the lin-ear fit is observed for low voltages.This is probably due to the effect of the residual damage present in this sample ͓see Fig.1͑a ͔͒.The second sample with a lower defect concentra-tion does not show a strong deviation from linear behavior.In any case the DLTS measurements were performed in the range of Ϫ7Ϭϩ0.3V and then in a region where the behav-ior is almost linear.On these diodes we have performed DLTS measure-ments by applying a reverse bias of 7V and a forward filling pulse of 0.3V for 1ms.To be sure that the duration of the filling pulse was sufficient to fill all the traps we have also performed measurements with a different filling pulse dura-tion:5ms.The resulting spectra were almost the same so we can conclude that 1ms is sufficient to fill all traps present in the analyzed region.The depletion region of the polarized diode includes the region containing voids,moreover,we have monitored the capacitance signal to be sure to observe the characteristic capacitance transient typical of majority and minority carriers.The DLTS signal is plotted as a func-tion of the measuring temperature in Fig.3,where the solid and the dashed lines refer to samples annealed at 800°C and 1000°C for 5min,respectively.In the former,three peaks are evident,and at decreasing temperature of analysis they are:the first two traps for majority carrier,electrons in our sample,and the third is a minority carrier ͑hole ͒trap.Their activation energies are,respectively,E C ϪE T ϭ0.55eV,E C ϪE T ϭ0.55eV,and E V ϩE T ϭ0.45eV.The first peak,the one at the highest temperature,is very broad,and it is prob-ably related to the presence of dislocations in the sample.Also for the sample annealed at 1000°C for 5min three peaks are evident,with activation energies given by:E C ϪE T ϭ0.58eV,E C ϪE T ϭ0.57eV,and E V ϩE T ϭ0.52eV.The energy localization in the silicon band gap of all centers was determined by measuring the emissivity at different temperatures.The experimental points and related fits are reported in the Arrhenius plot of Fig.4.The crossdots and the solid circles were carried out by measurements respectively on the sample annealed at 800°C or 1000°C.From this figure it is clear that different trap levels can have the same activation energy but different capture cross sec-tions.Indeed,the slope determines the activation energy while the capture cross section is related to the vertical axis intercept.The trap centers depend on the void characteristics,differing slightly in the cases studied,but they maintain a fundamental feature:The energy levels introduced are near the middle of the band gap while traps are present for both carriers.Because of these features,voids can be used to con-trol efficiently the minority carrier lifetime,and thanks to their high spatial localization they can become very useful in controlling locally the minority carrier lifetime.Moreover,there are quite clear differences between traps introduced by extended defects and voids.Only a few well-defined levels are introduced by voids while,in general,a spread in levels introduced by the presence of extended de-fects is observed,depending on defect type and dimensions.Moreover,extended defects grow at increasing temperature and to confine them in sharp regions becomes difficult.To evaluate the capability of the void induced trap levels to increase the recombination current in the transistor base we studied their characteristics when voids are formed in the base.In particular,parasitic transistors usually have a very low gain,close to 1,but normally an even smaller value is required.So,we fabricated transistors with a low gain to verify the possibility to use voids to further decrease it,by increasing the recombination in the base.The cross section TEM analyses of transistors implanted with different helium doses are reported in Figs.5͑a ͒and 5͑b ͒.For the lower He implanted dose ͑1ϫ1016/cm 2͒no voids are formed and the primary damage produced during He implantation collapses into extended defects ͓see Fig.5͑a ͔͒.At an implant dose of 3ϫ1016/cm 2voids are already visible in cross sections ͑not shown ͒and at an implanted dose of 6ϫ1016/cm 2their con-centration is quite large as can be observed in the TEM im-age of Fig.5͑b ͒.At very large implanted doses ͑1ϫ1017/cm 2͒the void concentration is even larger and a network ofdislo-FIG.3.DLTS signal in arbitrary units ͑a.u.͒as a function of the temperature of analysis performed on diodes annealed at 800°C ͑continuous line ͒and 1000°C ͑dashed line ͒.FIG.4.Arrhenius plot of emissivity obtained for voids annealed at different temperature.The values of the sample annealed at 1000°C are reported in the upper part of the figure while the values in the bottom refer to the sample annealed at 800°C.cations associated with all them appears.Dislocations asso-ciated with the presence of voids were always observed,con-fined in the void layer and,when a high density of voids is induced in the sample,they form a continuous network.These dislocations are different than those observed for low dose He implants when no void is formed after annealing.In the case of low dose He implants,the radiation damage col-lapses in extended defects during annealing ͑T Ͼ900°C ͒,as known for light ion implants in silicon.1During subsequent thermal processes,these dislocations extend from the pro-jected range to the surface.When voids are formed no dis-locations associated with the annealing of primary damage were observed in the cross-section TEM analyses performed in the two beam condition,even exciting different spots than ͑220͒.Increasing the void density,dislocations confined in the void layer and in all cases joining different voids are observed.The difference between the transistor gain with and without voids can be better quantified by the analyses of the Gummel plots reported in Fig.6.In a Gummel plot,the collector and the base current are plotted as a function of the base voltage.The transistor gain can be obtained directly from the ratio between the collector current and the base current in the linear region.If recombination occurs in the base the collector current decreases and the lower gain can be immediately monitored.The measurements were per-formed with an emitter-collector voltage V CE ϭ1V.The Gummel plot for a reference transistor is reported in Fig.6͑a ͒;it should be remarked that it is the same for all the reference transistors.The Gummel plot obtained from a tran-sistor implanted with 1ϫ1016/cm 2helium ions shows a clear decrease of the gain ͓Fig.6͑b ͔͒.It is essentially due to the lower value of the collector current generated by the elec-trons that reach the collector region.Due to the recombina-tion in the base,induced by traps associated with the pres-ence of voids,the number of electrons reaching the collector is clearly decreased.The collector current is even less in the case of an implant at 6ϫ1016/cm 2.The gain ͑h FE ͒has a func-tion of the implanted dose is reported in Table I for several helium implant doses.We can note that while the gain de-creases monotonically with increasing implant dose,it de-creases dramatically as soon as voids are formed in the sample ͑3ϫ1016He/cm 2͒.Then,the efficiency of traps,asso-ciated with the presence of voids,in decreasing the gain is quite higher than that of traps associated with the presence of extended defects.Several static characteristics of the transistors were also measured and compared.We have not observed any differ-ence in the emitter-base breakdown voltage between transis-tors with and without voids.The leakage current of this junc-tion is slightly higher when voids are present and it is identical in all the helium implanted transistors.However,the breakdown of the emitter-base junction is soft intransis-FIG.5.͑a ͒cross sections TEM analysis on transistors implanted with 300keV helium implants at 1ϫ1016/cm 2and ͑b ͒at 6ϫ1016/cm 2,and subse-quently annealed at 920°C for 30min during the formation of theemitter.FIG.6.Gummel plots for ͑a ͒a reference transistors,͑b ͒for a transistor implanted with 1ϫ1016/cm 2,and ͑c ͒with 3ϫ1016/cm 2.In all cases V CE ϭ1V.TABLE I.Transistor gains at increasing implanted helium doses.Helium dose ͓cm Ϫ2͔h FE ͑I B ϭ200mA ͒0 3.5–4.01ϫ10160.8–0.93ϫ1016 1.7ϫ10Ϫ36ϫ1016 5.0ϫ10Ϫ41ϫ10173.5ϫ10Ϫ5tors implanted with He at6ϫ1016and1ϫ1017/cm2.The depletion layer of the emitter-base junction does not reach the void band since the junction is at a depth of0.5m and the void band starts at a depth of1m,while the depletion layer is only0.12m at6V.However,the electrons ther-mally generated in the void layer can reach the emitter-base junction by diffusion.In fact,the diffusion length of elec-trons is30m considering a lifetime of only1s,that is reasonable in our case.This can explain the soft characteris-tics of transistors implanted with the highest helium doses. IV.CONCLUSIONThe void concentration,formed in silicon by helium im-plants and subsequent annealing to induce helium evapora-tion,can be controlled by the implantation dose and the an-nealing temperature.Deep level transient spectroscopy measurements performed on diodes containing voids formed at different annealing temperatures show the presence of three well-defined trap levels near the silicon band gap for both carriers.Transistor gain measurements reveal a system-atic decrease in the transistor gain when voids are present in the base.Gummel plots show that when voids are formed the collector current monotonically decreases in transistors im-planted with increasing helium doses.However,as soon as voids are formed in the base,the transistor gain decreases abruptly.These characteristics make them ideal for lifetime control in reducing parasitic transistor gain.1E.Rimini,Ion Implantation:Basics to Device Fabrication͑Kluwer Aca-demic,Boston,1995͒.2S.Coffa,N.Tavolo,F.Frisina,G.Ferla,and S.U.Campisano,Nucl. Instrum.Meth.B74,47͑1993͒.3M.M.Catania,F.Frisina,N.Tavolo,G.Ferla,S.Coffa,and S.U.Camp-isano,IEEE Trans.Electron Devices ED39,2745͑1992͒.4S.D.Brotherton and P.Bradley,Solid State Electron25,119͑1982͒.5B.J.Baliga,IEEE Trans.Electron Devices ED24,685͑1977͒.6S.M.Myers,D.M.Follstaedt,G.A.Petersen,C.H.Seager,H.J.Stein, and W.R.Wampler,Nucl.Instrum.Methods B͑in press͒.7S.M.Myers,D.M.Follstaedt,and D.M.Bishop,MRS Symp.Proc.316, 33͑1994͒.8D.M.Follstaedt and S.M.Meyers,MRS Symp.Proc.316,27͑1994͒. 9V.Raineri,P.G.Fallica,G.Percolla,A.Battaglia,M.Barbagallo,and S. U.Campisano,J.Appl.Phys.78,3727͑1995͒.10S.E.Donnelly,Radiation Effects90,1͑1985͒.11C.C.Griffoen,J.H.Evans,P.C.De Jong,and A.Van Veen,Nucl. Instrum.Meth.B27,417͑1987͒.12V.Raineri,A.Battaglia,and E.Rimini,Nucl.Instrum.Meth.B96,249͑1995͒.13S.M.Myers and D.M.Follstaedt,J.Appl.Phys.65,311͑1989͒.14C.H.Seager,S.M.Myers,R.A.Anderson,W.L.Warren,and D.M. Follstaedt,Phys.Rev.B50,2458͑1994͒.。