Pulsed laser deposited Al-doped ZnO thin films for optical applications

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AZO纳米线使用NAPLD技术

Fabrication of nanowires of Al-doped ZnO using nanoparticle assisted pulsed laser deposition (NAPLD)for deviceapplicationsS.Thanka Rajan a ,B.Subramanian a ,⇑,A.K.Nanda Kumar a ,M.Jayachandran a ,M.S.Ramachandra Rao ba ECMS Division,CSIR –Central Electrochemical Research Institute,Karaikudi 630006,India bDepartment of Physics,Indian Institute of Technology Madras,Chennai 600036,Indiaa r t i c l e i n f o Article history:Received 24June 2013Received in revised form 30August 2013Accepted 7September 2013Available online 26September 2013Keywords:NAPLD Thin ﬁlms Al doped ZnO Nanowiresa b s t r a c tAluminium doped zinc oxide (AZO)nanostructures have been successfully synthesized on sapphire sub-strates by using nanoparticle assisted pulsed laser deposition (NAPLD)in Ar atmosphere without using any catalyst.The growth of the AZO nanowires has been investigated by varying the argon ﬂow rates.The coatings have been characterized by X-ray diffraction (XRD),Field emission scanning electron microscopy (FESEM),Atomic force microscopy (AFM),Diffuse Reﬂectance Spectroscopy (DRS),Laser Raman spectroscopy and Photoluminescence spectroscopy.The results of XRD indicate that the deposited ﬁlms are crystalline ZnO with hexagonal wurtzite structure with (002)preferred orientation.FESEM images also clearly reveal the hexagonal structure and the formation of nanowires with aspect ratios between 15and 20.The surface roughness value of 9.19nm was observed from AFM analysis.The optical properties of the sample showed that under excitation with k =325nm,an emission band was observed in UV and visible region.The characteristic Raman peaks were detected at 328,380,420,430cm À1.Ó2013Elsevier B.V.All rights reserved.1.IntroductionZinc oxide (ZnO)is one of the most important metal oxide semi-conductors.This material has good electrical and optical properties and it is chemically stable.It has a wide direct band gap of 3.37eV with a large binding energy of 60meV [1].Undoped ZnO thin ﬁlms generally exhibit n-type conductivity due to intrinsic donors,such as oxygen vacancies and Zn interstitials [2].It has an open struc-ture,with a hexagonal close-packed lattice where Zn atoms occupy half of the tetrahedral sites,while all the octahedral sites are empty [3].This crystal structure offers plenty of sites to accommodate intrinsic defect and extrinsic dopants.The wurtzite structure of ZnO can be described as a series of alternating planes of tetrahe-drally coordinated O 2Àand Zn 2+ions stacked along the c -axis;this characteristic polarity of the surfaces gives rise to different nano-structures (nanorods,nanowires,nanobelts,nanotubes)under proper growth conditions [4].Such nanostructures show different and superior properties over their bulk counterparts due to their small size and large surface to volume ratio [5].Impurity-doped ZnO ﬁlms also show stable electrical and optical properties.Aluminium doping in zinc oxide (AZO)is a promising material due to its high conductivity and good optical properties [6].The choice of Al as donor dopant for ZnO over higher valence ions is lar-gely owing to its ease of incorporation in the ZnO structure;more-over it decreases the resistivity of the host ZnO without impairing the optical transmission in thin ﬁlm form [7].Both ZnO:Al and Al 2O 3are transparent to visible light,making them interesting can-didates for optical applications.Nowadays,pure ZnO or AZO are being actively investigated as alternative materials to indium tin oxide (ITO)because it is nontoxic,inexpensive and have long term environmental stability [8–10].Several deposition techniques have been routinely used to grow AZO nanostructures.The most common methods are magnetron sputtering [11,12],pulsed laser deposition (PLD)[13],chemical va-por deposition [14],and chemical spray [15].PLD is an attractive method,compared to magnetron sputtering and reactive RF sput-tering techniques,for deposition of ZnO thin ﬁlms with high struc-tural homogeneity and crystalline quality [16].Compared with other techniques PLD has many advantages such as (i)the compo-sition of the ﬁlms are close to that of the target,(ii)surface of the ﬁlm is smooth and (iii)good quality ﬁlm can be deposited [17].Nanoparticle assisted pulsed laser deposition (NAPLD)is a rela-tively new modiﬁcation of the PLD technique in which nanowires can be grown at high temperatures and high pressures without using any catalyst.This technique also gives ﬁlms with almost the same composition as that of the target.This advantage scores highly when compared to the other modiﬁed deposition tech-niques [18].In NAPLD the nanoparticles that are formed in the background gas by laser ablation are used for the subsequent growth of the nanowires [18].The initial nanoparticles formed in the laser ablation plume by the condensation are transported onto the substrate and act as starting materials for nano-crystal growth [19].In this work,we report the successful synthesis of AZO nano0925-8388/$-see front matter Ó2013Elsevier B.V.All rights reserved./10.1016/j.jallcom.2013.09.046Corresponding author.Tel.:+914565241538;fax:+914565227713.E-mail address:subramanianb3@ (B.Subramanian).wires on sapphire substrates by NAPLD at different argonﬂow rates without any catalyst.The structural and optical properties of the nanowires are also discussed in this paper.2.ExperimentalThe depositions of Aluminium doped ZnOﬁlms were carried out in the NAPLD system.The target preparation procedure is shown in Fig.1.The AZO target was prepared by mixing98mol%ZnO and2mol%Al2O3(99.99%pure,Sigma Aldrich). The sapphire substrate was cleaned byﬁrst boiling it in trichloroethylene and then ultrasonically cleaned in acetone for3min followed by milli pore water.AZO thin ﬁlms were deposited on sapphire substrates using frequency triplet,Q switched Nd:YAG laser.Fig.2shows a schematic diagram of the NAPLD system.The target was loaded into the target holder and the substrate was stuck on the substrate holder using silver paste.The target and substrate holder are placed inside a fur-nace,so the whole atmosphere with target and substrate are heated.When the tem-perature reached1000°C,the laser was switched on for ablating the target and Ar gas was let in.The AZOﬁlms were deposited on sapphire substrate for different ar-gonﬂow rates(200,300,400and500sccm)for30min.The optimized deposition parameters and conditions are described in the Table1.Theﬁlms were characterized by Bruker D8Advance to study the phases and for grain size measurement.The surface morphology of the preparedﬁlms was studied using Quanta3D FESEM.Atomic force microscopy for topographic studies was done by Agliant technologies(model5500).PL spectral analyses were performed using Cary Eclipse(Varian)and Raman spectroscopy for micro-structural analysis was done by Renishaw in via laser Raman microscope.Hall Effect measurements(Eco-pia,HMS3000)were made on the AZOﬁlms at a constant magneticﬁeld of 1.02T.Diffuse reﬂectance spectra of theﬁlms were recorded using Ocean Optics (USB2000)spectrophotometer.BaSO4powder compact was used as a standard ref-erence.The diffuse reﬂectance(R)was measured as a function of wavelength rang-ing from300to700nm.3.Results and discussion3.1.Structural and compositional analysisThe XRD patterns of the AZO thinﬁlm for different Argonﬂow rates(200–500sccm)on sapphire substrates are shown in Fig.3. It was observed that the wurtzite structure of the ZnO is unaffected by the doping of2mol%Aluminium.The diffraction patterns were equivalent,since the Al doping did not show any signiﬁcant shifts shift is because of the decrease of the lattice constants a and c with increasing argonﬂow rate.At lowﬂow rates of the inert gas,the growth mechanism is lateral growth over the substrate surface with uniform coverage.Therefore,a strain can be induced in the lattice of the AZO owing to the strained interface.At higherﬂow rates,the mechanism varies to condensation in the vapor phase leading to perfect needle type nano wire,which are under signiﬁ-cantly lower stress,with lattice parameters approaching that of an ideal single crystal,although not exactly,owing to the incorpora-tion of Al into the Zn sublattice.Therefore,due to the preferential growth along the[0001]direction,a strain can be induced in the lattice of the AZO by the strained substrate/ﬁlm interface.This might have led to a change in lattice constants.High texture in (002)will determine the quality of the nano wire.At400sccm ﬂow rate,the(004)line at72°is detected and intensity of the (002)also increased,indicating that the quality of theﬁlm was im-proved when the argonﬂow rate was increased.This shows that the crystallinity of the AZO thinﬁlms increased withﬂow rate. AZOﬁlms become polycrystalline,which means theﬁlm is com-posed of many grains with crystallographic orientations(100), (002),(101),(110),and(004)as indicated in Fig.3.The grain size(D)for various argonﬂow rates was calculated from the standard Scherer’s formula,expressed asD¼0:94kb cos hð1Þwhere k is the wavelength of Cu K a X-radiation(1.5406Å),b is the Full width at half maximum(FWHM)value for a particular orienta-tion calculated from the XRD pattern and h is the Braggs’angle.The calculated grain size for different argonﬂow rates(200–500sccm) for(002)peak were77.8,60,86.8and181.5nm respectively. The general trend seems to be that the crystallinity of theﬁlm also increases with the argonﬂow rate.Fig.4a–e compares the surface morphology of the ZnOﬁlms grown under different Arﬂow rates observed by FE-SEM.Films deposited at200sccm the lowﬂow rate regime–show a rather dense formation of ZnO grains growing laterally on the substrate surface with uniform coverage(Fig.4a).There is no evidence of the formation of thin ZnO wires.The wire-type morphology ap-pears only with increasingﬂow rates.Fig.4b shows the morphol-ogy ofﬁlm coated at300sccm.Some agglomeration is observed along with clusters randomly dispersed on the substrate.Interest-ingly,appearance of a thin needle-like structure is also seen.Fig.4c shows a SEM image of theﬁlm deposited at400sccm of Ar.While a number of vertically growing nano rods can be discerned in the microstructure,observation of the crystals along a direction nor-mal to{0001}shows aﬁner structure of the nano rods that consist of a layered arrangement of ZnO crystals,but neatly stacked along the c axis,suggestive of growth by oriented attachment mecha-nism[20].Such a layered growth produces corrugated10 10side walled nano rods as the layered structure is partially fused be-tween the stacks,probably by diffusional sintering.Clearly,this seems to be a preliminary step towards the perfect needle type nano structures observed at500sccm,shown in Fig.4d and e. Theﬁlm at500sccm,is homogeneous and comprises of nanowires and nanorods of diameters ranging from150to250nm and the lengths from3to10l m grown along the c-axis,clearly showing the hexagonal lattice of ZnO with wurtzite structure.They appear well aligned in a vertical plane of the substrate and have perfect hexagonal shape.Based on these observations,it is evident that the inert gas(Ar)ﬂow rate plays a crucial role in con-trolling the morphology of the ZnOﬁlms.At lowﬂow rates,the partial pressure of Ar in the vapor is too low to produce any con-densation within the vapor and hence,uniform coverage of the substrate is seen.With increasingﬂow rate of the Ar gas,the ener-getic Zn and O species from the ablated target rapidly lose theirFig.1.Flow chart of target preparation.612S.Thanka Rajan et al./Journal of Alloys and Compounds584(2014)611–616energy by colliding with the colder Ar atoms and nucleate into nano particles within the vapor phase which subsequently act as seeds for the nanocrystalline growth.This mechanism is akin to the inert gas condensation technique and explains the formation of perfectly grown ZnO wire under optimized Ar ﬂow rateconditions.The gradual change from uniformly grown ﬁlms with lateral spread to vertical nano rods by varying the inert gas ﬂow rate also introduces a slight straining of the lattice which is also reﬂected in changes in lattice parameter observed by XRD.The nano rods deposited at 500sccm have a low defect density and hence an unstrained lattice,whereas those deposited at 300sccm have a considerable strain due to bonding with the substrate.AFM studies were carried out to investigate the effect of Al dop-ing concentration on surface roughness of the ﬁlms.Fig.5shows that the surface of the ﬁlm is covered with grains of diameter about 50nm.The root mean square (rms)surface roughness of the ﬁlm was measured to be 9.19nm.The elemental composition analyses were carried out on Al doped ZnO nanowires using Energy dispersive X-ray (EDX)analysis and is shown in Fig.6.The presence of Zn,Al and O was observed in the AZO samples.No impurity phases were detected on the surface of the ﬁlm.The different Hall parameters such as Hall mobility (cm 2V À1s À1),resistivity (X cm)and carrier concentration (cm À3)have been measured for the ﬁlms deposited at 500sccm.From the previous observation it is optimized that 500sccm shows high X-ray diffraction intensity and the SEM images also reveal that 500sccm is an apt parameter for our studies.Analysis of the equi-librium defect concentration in Al doped ZnO reveals that for each Al 3+that substitutes for one Zn 2+,a free electron is released into the crystal to enhance its conductivity,according to the relation (in Kröger–Vink notation):Al 2O 3ðZnO Þ 2Al Zn þ2O o þ2e 0þ12O 2ð2ÞIn this case,the Al dopant concentration has been ﬁxed at 2mol%,and we assume that the O 2partial pressure does not vary signiﬁcantly with the Ar ﬂow rate.The electronic charge conduc-tion should control the net resistivity of the ﬁlm at low frequen-cies.The carrier concentration of the AZO ﬁlm determined by Hall effect measurement is 8.07Â1019.Hall mobility and resistiv-ity were measured as 25.28cm 2V À1s À1and 1.028Â10À2X cm,which agrees clearly with the values reported by Pin-Chuan Yao et al.[21].3.2.Optical propertiesRaman scattering is an effective technique to investigate the crystallization,structure and defects chemistry of ser Raman spectra of the nanostructured AZO ﬁlms are shown in Fig.7.Wurtzite structure belongs to the space group C 46v with two formulae units per primitive cell,where all atoms occupy C 3v sites.Twelve vibrational modes exist in the ZnO unit cell;one longitudinal acoustic (LA),two transverse acoustic (TA),threeFig.2.Schematic set up of nanoparticle assisted pulsed laser deposition.Table 1Deposition parameters and conditions.SpeciﬁcationParameters LaserNd:YAG (355nm)Repetition rate 10Hz 4ns140mJ/pulse 2–4J cm À2Sintered AZO Sapphire 1000°C Argon $2mbar200–500sccmXRD pattern of AZO ﬁlms grown on sapphire substrate at different ﬂowlongitudinal-optical(LO),and six transverse optical(TO).A1and E1 symmetries are polar and split into LO and TO components with different frequencies[22].The Raman peaks near328,380,420,430and465cmÀ1can be attributed to the wurtzite crystal structure of AZO.The dominant peak at430cmÀ1indicates the Wurtzite structure of ZnO and is attributed to the high E2mode of non polar optical phonons.E2 high mode is for ZnO hexagonal structure with vibrations of O sub-lattice.The FWHM of the E2line is about8cmÀ1which is another indication of the high quality of the NAPLD synthesized nanocrys-talline ZnOﬁlms.The peak at380,420and465cmÀ1corresponds to A1(TO),E1(TO)and A1(LO)respectively.The peak A1measured at328cmÀ1is related to multiple phonon scattering process.A slight shift was also observed which was due to the doping of AlFig.4.FESEM images for AZOﬁlm at(a)200sccm,(b)300sccm,(c)400sccm,(d and e)500sccm.Fig.5.A representative AFM image of AZOﬁlm.Fig.6.Energy dispersive X-ray analysis of AZO nanowires on sapphire substrate.without introduction of any additional stress within the samples shown in XRD.Diffuse reﬂectance spectral studies in the UV–visible region were carried out to estimate the optical band gap of the nanostruc-turedﬁlm.The optical diffuse reﬂection spectra of AZO samples differentﬂow rates(200–500sccm)on sapphire substrate are dis-played in Fig.8.The energy band gap E g can be determined from onset of the linear increase in the diffuse reﬂectance.From2weﬁnd that the band gap of the AZOﬁlm lies in the range 3.40–3.44eV using Einstein’s energy relation:1:24kðl mÞwhere E is the band gap and k is the wavelength.The band gap increases with increasing Arﬂow rate.The in-crease in E g may be due to the increase of electron concentration. Generally,the values for band gap of AZOﬁlms are slightly higher. The conduction electrons in the ZnOﬁlms are supplied from donor sites associated with oxygen vacancies or excess metal ions[23] The band gap of ZnO is in the near UV region which is3.37 The AZO reﬂection starts at about380nm and the samples exhib-ited absorption peaks in the visible region at about660nm in both spectra.The photo luminescent emission spectrum of AZOﬁlms for the various argonﬂow rates are shown in Fig.9.The PL peaks for all the samples are almost same in position but different in intensity.They show near-band edge emission around373nm which is the UV re-gion;this emission is due to ZnO.The visible emission was ob-served at around405nm,468nm and533nm due to defect emission.The blue peak at468nm comes from the electron transi-tion from Zn interstitial level to the top of the valance band.The green emission observed at533nm resulted from intrinsic defects. Deep level emissions are associated with intrinsic defects such as oxygen vacancies or zinc interstitials[24].From Table3weﬁnd that the calculated band gaps are approx-imately equal to the band gap of ZnO.So the ZnO phase is con-ﬁrmed with the band gap in the UV absorption region.However, the UV emission intensity increases and the deep level emission intensity decreases as argonﬂow rate increases from200to 500sccm suggesting that the crystals grown at higherﬂow rates have lower defect densities in their lattice.This observation is in agreement with the XRD results suggesting that defect densities decrease with increasing Arﬂow rates,along with the correspond-ing change in the lattice parameter.ser Raman spectra of AZOﬁlms on sapphire substrates.Fig.8.DRS patterns of AZOﬁlms on sapphire substrates.Fig.9.PL emission spectra of AZOﬁlms on sapphire substrates.Table3Band gap values of AZOﬁlm on sapphire substrate determined from the PL spectrum.Rgonﬂow(sccm)Wavelength(nm)Band gap(eV)200364.2 3.32300365.9 3.32400364.9 3.31500355.7 3.334.ConclusionWe have used a relatively new technique,nanoparticle assisted pulsed laser deposition(NAPLD),to grow AZO nanostructures. Deposition of AZO on sapphire using NAPLD was done at high tem-perature and high pressure,without using any catalyst.XRD and EDAX characterization shows that AZO belongs to the most stable wurtzite type with the presence of Zn,Al and O on the surface of theﬁlm.SEM analysis reveals the formation of nanowires.Band gap of these nanostructures increases from3.37to3.41.Surface topology was studied by AFM imaging of the surfaces of AZOﬁlms deposited at high temperature and the RMS roughness was deter-mined.XRD and Raman measurements showed that Al ions were incorporated into the ZnO lattice.Photo luminescent emission spectrum of AZOﬁlms show near-band edge emission around 373nm in the UV region corresponds to ZnO.Increase in the inert gasﬂow rate seems to reduce defect densities and corresponding with a decrease in the defect level emission intensities in the PL spectra.AcknowledgementsOne of the authors(S.T)thanks Dr.E.Senthil Kumar and F.Bel-larmine for their help in doing the NAPLD process.References[1]S.Tewari,A.Bhattacharjee Pramana,J.Phys.76(1)(2011)153–163.[2]Kyong-Kook Kim,Hitoshi Tampo,June-O Song,Tae-Teon Seong,Seong-Ju Park,Ji-Myon Lee,Sang-Woo Kim,Shizuo Fujita,Shigeru Niki,Jpn.J.Appl.Phys.44 (7A)(2005)4776–4779.[3]Chundong Li,Jinpeng Lv,Bo Zhou,Zhiqiang Liang,Phys.Status Solidi A209(8)(2012)1538–1542.[4]Rodrigo Noriega,Jonathan Rivnay,Ludwig Goris,Daniel Kälblein,Hagen Klauk,Klaus Kern,Linda M.Thompson,Aaron C.Palke,Jonathan F.Stebbins,Jacob R.Jokisaari,Greg Kusinski,Alberto Salleo,in:J.Appl.Phys.107(2010)074312-1–074312-7.[5]M.Mozibur Rahman,M.K.R.Khan,M.Raﬁqul Islam,M.A.Halim,M.Shahjahan,M.A.Hakim,Dilip Kumar Saha,Jasim Uddin Khan,J.Mater.Sci.Technol.28(4) (2012)329–335.[6]S.M.Park,G.H.Gu,C.G.Park,Phys.Status Solidi A208(2011)2688–2691.[7]H.Kim,J.S.Horwitz,S.B.Qadri,D.B.Chrisey,Thin Solid Films420–421(2002)107–111.[8]Sang moo Park,Tomoaki Ikegami,Kenji Ebihara,Jpn.J.Appl.Phys.45(2006)8453–8456.[9]S.Suzuki,T.Miyata,M.Ishii,T.Minami,Thin Solid Films434(2003)14–19.[10]B.Szyszka,Thin Solid Films351(1999)164–169.[11]Z.Le,W.Gao,Mater.Lett.58(2004)1363–1370.[12]Z.G.Yu,P.Wu,H.Gong,Appl.Phys.Lett.88(2006)132114–132116.[13]F.K.Shan,B.C.Shin,S.C.Kim,Y.S.Yu,J.Korean Phys.Soc.42(2003)S1374–S1377.[14]Y.Natsume,H.Sakata,T.Hirayama,H.Yanagada,J.Appl.Phys.72(1992)4203–4207.[15]H.Mondragon Suarez, A.Maldonaldo,M.de la,L.Olvera, A.Reyes,R.Castanedo-Perez,G.Torres-Delgado,R.Asomoza,Appl.Surf.Sci.193(2002) 52–59.[16]V.Cracium,J.Elders,J.G.E Gardeniers,I.W.Boyd,Appl.Phys.Lett.65(1994)2963–2965.[17]A.V.Singh,Manoj Kumar,R.M.Mehra,Akihiro Wakahara,Andakira Yoshida,J.Indian Inst.Sci.81(2001)527–533.[18]Y.N.Xia,P.D.Yang,Y.G.Sun,Y.Y.Wu,B.Mayers,B.Gates,Y.D.Yin,F.Kim,Y.Q.Yan,Adv.Mater.15(2003)353–389.[19]Tatsuo Okado,Ruqian Guo,Jun Nishimura,Masato Matsumoto,MitsuhiroHigashihata,Daisuke Nakamura,Thin Solid Films447–448(2004)33–39.[20]Shilei Xie TengZhai,Yexiang Tong,mun.14(2012)1850–1855.[21]Pin Chuan Yao,Shih Tse Hang,Yu Shuan Lin,Wen Tsai Yen,Yi Cheng Lin,Appl.Surf.Sci.257(2010)1441–1448.[22]A.Singh,A.Kumar,N.Suri,S.Kumar,M.Kumar,P.K.Khanna,D.Kumar,J.Optoelectron.Adv.Mater.11(6)(2009)790–793.[23]M.Suchea,S.Christoulakis,N.Katsarakis,T.Kitsopoulos,G.Kiriakidis,ThinSolid Films515(2007)6562–6566.[24]K.J.Chen,T.H.Fang,F.Y.Hung,L.W.Ji,S.J.Chang,S.J.Young,Y.J.Hsiao,Appl.Surf.Sci.254(2008)5791–5795.616S.Thanka Rajan et al./Journal of Alloys and Compounds584(2014)611–616。

双源气溶胶辅助化学气相沉积制备AZO薄膜

双源气溶胶辅助化学气相沉积制备AZO薄膜秦秀娟;王晓娟;张丽茜;王丽欣;柳林杰【摘要】Al⁃doped ZnO thin films were prepared on glass substrates with different proportions of ethanol and methanol solution by dual⁃source aerosol⁃assisted chemical vapor deposition method. The structure, morphology, optical and electrical properties were investigated by X⁃ray diffractometer, atomic force microscope, SEM, UV⁃vis double beam spectrophotometer and 4 point probe method. AZO thin films exhibited strong growth orientation along the ( 002) plane by the dual⁃source AACVD method. When the ethanol and methanol was 15mL and 20mL, respectively, the AZO thin film had best crystallization and had optimal electro⁃opotical properties. The films exhibited different morphologies with different proportions of ethanol and methanol solution.%采用双源气溶胶辅助化学气相沉积法制备了Al掺杂ZnO薄膜。

Al掺杂纳米氧化锌导电粉的性能与结构

ＺｎＯ在室温下禁带宽度为３．３７ｅＶ，是一种自激
天然的氧化锌ｎ型导电，氧化锌有６种点缺陷，其中氧空位和锌间隙原子被认为是主要点缺陷，氧空位是一种深施主缺陷，锌间隙则是浅施主缺陷，两者对于ｎ型导电性都有很重要的影响［７啊１“。本工作选择均相沉淀法制备Ａ１掺杂氧化锌导电粉，通过对掺杂比例以及工艺参数的考察，制备了导电性能良好的导电粉体，并对其结构进行了表征和研究。
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２．３扫描电镜与粒度分析图３（ａ）是掺杂量为１．５％Ａ１的氧化锌ＳＥＭ照片，图３（ｂ）是对应的ＥＤＳ能谱图。由图３（ａ）可以看出，颗粒为类椭球形，虽然已经尽量选取了低温煅烧，但是仍然未能避免团聚，颗粒的二次粒径明显增大；粒度分布的测量结果证实了这一点，样品的表面积平均粒径Ｄ［－３，２］为４．４６２肚ｍ，体积平均粒径Ｄ［４，３］为１４．３９４／，ｍ，而中位粒径ｄ（０．５）为９．６８９ｐ．ｍ。
随着现代工业的发展，高阻材料和静电敏感材料广泛应用于生产生活中，静电所带来的危害也日益严重。由于导电粉体具有抗静电、电磁屏蔽等性能，因而作为一种功能性填料被广泛应用于电子、机电、通讯、印刷、航空航天、兵器等工业部门的导电、电磁屏蔽、防静电领域ｕ’２］，如电脑、手机、电子医疗设备、电子仪器仪表等产品的电磁屏蔽、防静电。虽然传统的碳系、金属系和金属氧化物系的导电粉体仍然应用较广，但是Ｚｎ０以其独特的优势正在逐步替代它们的应用市场。ＺｎＯ作为导电粉体其化学性能稳定、分散性能良好，尤其是颜色浅、白度高且无毒性，再加上来源范围广，生产成本低廉，已成为该领域的研究热点，欧美国家已将这类产品广泛应用于飞机、导弹等高科技产品上［３“］。

脉冲激光沉积PLD法生长纳米ZnO薄膜的探索

72材料导报2008年5月第22卷专辑X脉冲激光沉积(PL D)法生长纳米Z nO薄膜的探索仇旭升1，谢可可1，孔明光2，汪壮兵1，刘炳龙1，马渊明1，章伟1，梁齐1 (1合肥工业大学理学院，合肥230011；2中国科学院合肥固体物理研究所材料物理重点实验室，合肥230031)摘要在Si衬底上用脉冲激光沉积法生长C轴取向高度一致的Z nO纳米薄膜。

实验制备Z nO纳米结构，其颗粒尺寸的控制是关键。

通过改变衬底温度(400～700℃)和沉积时间，获得不同的Z no纳米结构。

SE M观察，在600"C时颗粒均匀且间隔明显，且该薄膜结构为不连续膜，这与其他衬底温度下所形成的薄膜结构有很大差异。

X R D显示，600～700℃结晶良好。

关键词纳米薄膜PL D X R DS t udy of Z nO N a no Fi l m s P r e par e d by Pul s ed L a se r D eposi t i onQ I U X us hen91，X I E K ekel，K O N G M i ngguan92，W A N G Z hua ngbi n91，L I U B i ngl on91，M A Y uanm i n91，Z H A N G W e i l，L I A N G Q i l(1Sc hool of Sci ence，H ef ei U ni ve r si t y of T e chnol ogy，H e f e i230009；2K e y Labor at or y of M at er i a l s Phys i cs，I ns t i t ut e of Sol i d St at e P hy si c s，C h i ne se A cad em y of Sci e nces，H ef ei230031)A b s t r act C-ax i s or i en t ed Z n0na nof i l m s ar e pr ep ar e d o n s i l icon subst r at es by pul sed-l aser dep osi t i on(PL D)．T he s ize cont r ol of Z n Ona nof i l m s i s t he key of t he expe r i m ent．T he di f f er ent Z n0na nost r uc t ur e s ar e got by changi ngt he subst r at e t e m per at ur e and depos i t i on t i m e,The SE M i m a ge s ho w s t hat gr a i ns of Z n0na nof i l m s ar e di st r i but ed w i t hgoo d uni f or m i t y a nd di s ti nct i nt erval s w he n T|i S l ocat ed a t600℃and i t i s a di scont i nuous f i l m w h i c h i S m u ch di f f er entf r o m ot h er f i l m s．The r es u l t s of X-r ay di f f r act i on s how t hat t he nano er yst al l i ne Z no t hi n fi l m s ha ve a good cr yst als t r uc t ur e w hen丁I i S bet w een600℃a nd700℃．K ey w or ds nanof i l m s。

用于电致变色玻璃的氧化钒薄膜的研究进展

分析研究与探讨Doors&WindowsD0I：10.12258/j.issn.1673-8780.2021.01.063用于电玫变色玻璃的氧化钒薄膜的研究进展王科研1刘红英2宋羽茜2张远洋2梁小平1，1天津耀皮工程玻璃有限公司天津市节能玻璃企业重点实验室2天津工业大学材料科学与工程学院摘要：建筑能耗在我国所有能耗中的占比越来越高，而电致变色玻璃作为一种节能环保的绿色智能建筑材料将成为降低建筑物能耗的首选。

五氧化二钒（V20s）因其特殊结构和特性在智能窗中分别作为离子储存层和电致变色层成为研究热点。

本文从掺杂改性和纳米结构等方面综述了电致变色玻璃用V205变色层和离子储存层改性的研究进展。

关键词：五氧化二钒；电致变色玻璃；离子储存层；电致变色层Abstract：With the growing global energy consumption,the electrochromic device（ECD）technology has gained a lot of attention due to its great potential to reduce building energy consumption.vanadium pentoxide（V205）has become a research hotspot as electrochemical ionic storage films and electrochromic films in smart windows due to its special structure and characteristics.The modifications of V205 layer as electrochromic film and electrochemical ionic storage films for electrochromic glass are reviewed from doping and nanostructure .Key words：vanadium pentoxide,electrochromic glass,electrochromic films,electrochemical ionic storage films1前言目前建筑能耗占我国社会总能耗的27%左右，其中门窗能耗占其中的40%-50%m,节能建筑材料的应用是减少建筑物能耗的最有效途径,但是就现在国内的节能建筑材料而言,其科研和应用还是比较落后的。

射频溅射ZnO薄膜的晶体结构和电学性质

射频溅射ZnO 薄膜的晶体结构和电学性质黄静华　李德杰(清华大学电子工程系　北京　100084)Structures and Electric Properties of RF Sputtered Zn O FilmsHuang Jinghua ,Li Dejie(Department o f Electronic Engineering ,Tsinghua University ,Beijing ,100084,China ) A bstract Zn O films can be a promising material used in the electron transmission and acceleration layers in a field emission flat panel display because of its wide band gap (3.1eV )and low affinity (3.0eV ).The structures and electric properties of the ZnO films ,grown by RF magnetron sputtering ,were studied with X -ray diffraction spectroscopy (XRD ),scanning electron spectroscopy (SE M ).The results showed that the substrate temperature and the partial pressures of oxygen and argon gasses during sputtering affect the quality of the films .XRD results showed that high substrate temperature promotes crystallization of the fil m .The highl y textured film is made up of grains with their c -axis normal to the surface .The average size of crystal grains range about 50～60nm ,with a preferential growth orientation in (002)direction .Addition of s mall amount of oxygen may increase the breakdown electric field strength of the films .For example ,when the sputterin g gas was Ar +O 2(25%),the breakdown electric field stren gth increases from 0.17V /10nm to 0.35V /10nm ,as the substrate temperature rises from room temperature to 180℃. Keywords ZnOthin film ,RF sputtering ,Field emission displa y 摘要　氧化锌(Zn O )具有较宽的带隙(3.1eV )和较低的亲合势(3.0eV ),有可能用作薄膜场发射阴极中的电子传输层材料。

105 新型薄膜锂离子电池电极材料-脉冲激光沉积氟化银薄膜 (第十五届全国电化学会议-锂电专场论文集)

新型薄膜锂离子电池电极材料-脉冲激光沉积氟化银薄膜崔艳华1，2 汪小琳1李达2苏伟1 刘效疆1傅正文2（1. 中国工程物理研究院电子工程研究所, 四川绵阳 621900；2. 复旦大学化学系激光化学研究所，上海200433, cuiyanhua@）摘要：采用脉冲激光沉积法在不锈钢基片上制备了纳米结构的氟化银薄膜. 充放电测试显示该薄膜具有380 mAh·g-1的首次放电容量. 循环伏安曲线显示在1.9 V和2.2V处出现了一对可逆的氧化还原峰. X射线衍射表明沉积得到的是多种价态混合的氟化银薄膜. 该薄膜较高的放电平台和良好的可逆性显示了它作为薄膜电池正极材料的潜力。

关键词：氟化银薄膜, 脉冲激光沉积, 锂离子电池中图分类号：O646.3 文献标识码：AElectrochemical Properties of Silver Fluoride Films Fabricated by Pulsed LaserDepositionCUI Yan-Hua1 WANG Xiao-Lin1 LI Da2 SU Wei1 LIU Xiao-Jiang1 FU Zheng-Wen2*(1. Institute of Electronic Engineering, China Academy of Engineering Physics, Mianyang, Sichuan, 621900, China; 2. Department of Chemistry andLaser Chemistry Institute, Shanghai, 200433, China，cuiyanhua@)Abstract：Nanostructured Silver Fluoride thin films have been prepared by pulsed laser deposition (PLD) on stainless steel substrates. Charge and discharge curves show a high first diacharging capacity of about 380 mAh·g-1. Cyclic voltammograms show that a redox couple of reduction and oxidation peaks at 2.2 and 1.9 V appear for the first time. The structure of the as-deposited film was characterized by X-ray diffraction (XRD) and the result showed it is a composite film including silver fluorides with different valences. The advantage of electrochemical reversibility and stable discharging pleatue around2.0v showed its potential as a lithium storage material for lithium ion batteries.Key words：Silver fluoride thin film, Pulsed laser deposition, Lithium-ion batteries过渡金属氟化物由于分子量较低, 因此拥有较高的理论容量, 是一类值得研究的储锂材料. Li等系统地研究了过渡金属氟化物的电化学性能, 从热力学角度计算得到的理论容量和实际放电容量有很大差异, 他们认为氟化物的循环性能和放电后产物颗粒大小以及在氟化物中的分布形式有着密切关系[1-2]. Badway等制备出了碳与过渡金属氟化物的混合纳米颗粒, 提高了金属氟化物的电化学活性[3，4]. Makimura等报导了FeF3纳米薄膜的电化学行为[5]. 他们的实验结果显示FeF3纳米薄膜的充放电曲线与FeF3粉末电极的放电平台完全不同. 最近, 我们课题组采用脉冲激光沉积法制备了一系列过渡金属氟化物薄膜, 包括CoF2, NiF2, CuF2等, 研究结果显示它们具有各不相同的电化学活性和反应机理[6-8]. 本文利用脉冲激光沉积法 (PLD) 制备了纳米结构的氟化银薄膜电极, 测试了其作为锂离子电池电极材料的电化学性能。

PLD法硫化物半导体敏化TiO_(2)纳米棒阵列薄膜的研究进展

当代化工研究Modem Chemical Research154科研开发2021・05PLD法硫化物半导体敏化T i（J?纳米棒阵列薄膜的研究进展*孔书悦罗艳花吴楠马成李鹏冶晓英余鹏珍（西北民族大学化工学院甘肃730106）摘要：量子点敏化太阳能电池(QDSSCs)相较于其它电池具有较高的理论转化效率(66%)且其生产成本相对较低，受到太阳能业界的广泛关注切。

相较于其他太阳能电池，薄膜型电池可以降低太阳能发电的成本和缩小太阳能电池的体积，进而薄膜的制备成为太阳能电池性能好坏的关键性因素.目前大部分研究均针对于Cd系硫化物量子点展开，但由于其有较高毒性限制了Cd系硫化物在太阳能电池方面的发展。

本文详细介绍了制备无毒环保的硫化物量子点薄膜以及PLD法制薄膜的优势，并展望未来发展，为增强光电转化效率促进太阳能电池的发展提供新的思路。

关键词：量子点敏化太阳能电池；脉冲激光沉积；硫化物中图分类号：0文献标识码：AResearch Progress of Sulfide Semiconductor Sensitized TiO2Nanorod Array Films by PLD Kong Shuyue,Luo Yanhua,Wu Nan,Ma Cheng,Li Peng,Ye Xiaoying,Yu Pengzhen(College of Chemical Engineering,Northwest University for Nationalities,Gansu,730106) Abstract t Quantum dot sensitized solar cells(qdsscs)have high theoretical conversion efficiency(66%)compared with other batteries,and t heir p roduction costs are relatively loyv t which has attracted extensive attention of t he solar pared with other solar cells,thin f ilm solar c ells can reduce the cost ofsolar p ower generation and reduce the volume of s olar cells,and the p reparation of t hin f ilms has become a key f actor in th e performance of s olar cells.At p resent,most of t he researches are f ocused on Cd based sulfide quantum dots.Hoyvever,due to their high toxicity,the development of C d based sulfide in solar cells is limited.In this p aper,the advantages of p reparing non-toxic and environmentally f riendly sulfide quantum dot f ilms and PLD thin f ilms are introduced in detail,and the f uture development is prospected,which provides new ideas f or enhancing the p ho toelectric conversion efficiency and p romoting the development of s olar cells.Key words z quantum dot sensitized solar cell；pulsed laser deposition^sulfide1.引言随着社会经济的发展，全球能源消耗大幅度增加，人类正面临着严重的能源危机。

人大考研-理学院物理系研究生导师简介-于伟强

爱考机构-人大考研-理学院物理系研究生导师简介-于伟强凝聚态物性实验研究(点击次数：14393)于伟强(YuWeiqiang)个人信息(CV.PDF)职称：教授办公地点：理工楼707电子邮箱:wqyu_电话:10-62511971传真:10-62517887PersonalWebpage(English)实验室网址链接教育经历1992.9-1996.7北京师范大学物理系理学学士1996.9-1999.1北京师范大学物理系理论凝聚态物理硕士1999.1-2000.10(美国)南加州大学物理系(USC)理论凝聚态物理博士生2000.10-2004.6(美国)加州大学洛杉矶分校(UCLA)实验凝聚态物理博士工作经历2008.4-现在中国人民大学物理系教授2004.7-2008.3(美国)马里兰大学超导研究中心助理研究员2008.4-2008.10(加拿大)麦克马斯特大学物理系访问学者基金状况1）2008教育部，新世纪人才资助计划，负责2）2011-2013基金委面上项目（11074304），空穴掺杂和磷掺杂铁基超导单晶材料的核磁共振研究，负责3）2010-2014科技部973项目（2010CB923004），新型量子功能体系的物性表征及其材料探索，骨干4）2011-2015科技部973项目（2011CBA00100），高温超导材料与物理研究，骨干5）2013-2015基金委优秀青年资助，关联电子材料的核磁共振物性研究，负责讲授课程光学（2008，2009，2010，2011,2012，4-5学分）物理系本科新生研讨课（2012，1学分）教学服务2012级物理系本科班主任研究方向使用磁共振技术和输运测量，并结合低温高压等极端条件，研究量子磁性和非常规超导材料。

研究课题包括以下几个方面：1）非常规超导现象，包括高温超导、有机超导、重费米子超导、铁基超导等；2）低维自旋系统和量子相变现象，通过外加磁场和高压进行调制；2）磁性功能材料，包括多铁材料，具有磁性的拓扑绝缘体等；3）量子功能材料，结合微波测量技术。

射频磁控溅射沉积的ZnO薄膜的光致发光中心与漂移

射频磁控溅射沉积的Z nO薄膜的光致发光中心与漂移李伙全　宁兆元　程珊华　江美福(苏州大学物理科学与技术学院薄膜材料江苏省重点实验室,苏州　215006)(2003年4月15日收到;2003年6月2日收到修改稿) 利用射频磁控溅射法在n型单晶硅衬底上制备了ZnO薄膜.通过改变源气体中氩气和氧气的流量比制备了具有不同化学计量比的ZnO薄膜,并且将它们在真空中作了加热后处理来研究ZnO薄膜的光致发光特性.这些在常温衬底上沉积的薄膜可发出强的蓝光,其峰位会随氧流量的减少而发生红移.从导带底到锌缺陷形成的受主能级之间的跃迁可能是产生蓝光发射的原因.关键词:ZnO薄膜,光致发光,退火,蓝光发射PACC:6800,7855,8140G11引言ZnO薄膜是一种宽禁带(E g=313eV)直接带半导体,它的激子结合能(60meV)比G aN高许多,因此可能是一种优异的发光材料.ZnO薄膜的制备方法多种多样,如直流反应溅射法[1—3,6,7,17]、射频磁控溅射法[4,8,9]、脉冲激光沉积法[10]、反应蒸发法[5,11,13]、化学合成法[16]、溶胶沉淀法[18]等.Lin等人曾经报道使用直流反应溅射法制备的ZnO薄膜有两个光致发光(P L)中心:390nm左右的紫峰和520nm左右的绿峰[1,2].他们指出,紫峰可能来源于激子复合发光,而绿峰来源于氧和锌空位等本征缺陷.薄膜中的缺陷种类和浓度决定于制备方法和工艺条件[1—4,6,7,9,12].为了研究氧缺陷和锌缺陷对其发光特性的影响,本文采用射频磁控溅射法制备了ZnO薄膜,并且使用两种方法来改变薄膜中的氧缺陷和锌缺陷浓度,一是在制备时调节ArΠO2流量比;二是对其在缺氧的真空环境下作退火处理.制备时的氧分压和退火处理都会影响ZnO薄膜的化学计量比,从而改变薄膜中的氧缺陷和锌缺陷浓度.ZnO薄膜的P L光谱测量结果表明,氧缺陷和锌缺陷浓度的变化导致了薄膜P L中心峰位的漂移.21实验安排采用J G P2560D型磁控溅射仪制备ZnO薄膜,射频频率为1315MH z,输入功率为300W.纯度为99199%的ZnO靶的直径为512cm,靶到衬底的距离为4cm,沉积时硅基片的温度为室温.选用的源气体是氧气和氩气的混合物,溅射时的工作气压为2Pa.固定氩气的流量为5sccm,在Ar∶O2分别为5∶20,5∶10,5∶5时制备的样品标号依次为A,B,C;纯氩气下制备的样品标号为M,纯氧气下制备的样品标号为N.所有样品的沉积时间都是30min.使用台阶仪测试以上样品的厚度约为550nm.在纯氧环境下制备4块样品的标号依次为a,b,c,d,并对b,c,d三块样品做了真空加热后处理,退火温度分别为150, 300和450℃,保温时间都是45min.利用Hitachif24010型荧光分光计测试样品的P L 光谱,激发光源为功率为150W的氙灯,激发波长为230nm,测试的波长范围为300—650nm.31结果与讨论不同方法制备的ZnO薄膜的P L中心的峰位有所不同.Lin等人使用直流反应溅射锌靶在300℃硅基片上制备了ZnO薄膜[1,2],并且在空气中作了900℃后处理.这些样品的P L光谱中存在两个发光带:一个是峰值波长位于390nm的占优势的强而尖锐的紫光带,另一个是峰值波长位于520nm的较弱的绿光带.图1为使用射频溅射ZnO靶在几种Ar∶O2流量第53卷第3期2004年3月100023290Π2004Π53(03)Π0867204物　理　学　报ACT A PHY SIC A SI NIC AV ol.53,N o.3,March,2004ν2004Chin.Phys.S oc.图1　改变ArΠO2流量比制备ZnO薄膜的P L光谱　谱线A的Ar∶O2=5∶20,谱线B的Ar∶O2=5∶10,谱线C的Ar∶O2=5∶5比下制备的ZnO薄膜样品的P L光谱图.在较小氧流量Ar∶O2=5∶5时制备的样品C的P L光谱图中有三个主要的发光带,峰值波长分别位于390,420, 510nm的近紫外发光带、紫光带和绿光带.它的近紫外发光带低而弱,紫光带强而尖锐占据优势,而绿光带粗而宽.这与直流反应溅射法制备的ZnO引起的薄膜的P L光谱较接近[2].但是在增加了氧流量后制备的样品A和B的P L光谱发生了变化,绿光带消失,出现了峰值波长位于470nm左右的强而尖锐的蓝光带,而且原来分别位于420和390nm的紫峰和近紫外峰也分别向短波方向移到400和375nm.大量文献都指出,近紫外发光峰是源于导带和价带之间的带—带跃迁,而紫峰是源于自由激子复合[1—4,6,7,11,13].由于光激发形成自由激子所需要的能量比激发自由电子从价带跃迁到导带需要的能量小,因此自由激子复合发光的概率比带—带复合发光的概率大,自由激子复合发光的强度也更强.激子的存在与发光体的结晶状态密切相关,在结晶差的固体中存在的大量缺陷和杂质会造成激子的淬灭.我们的样品都是在室温下制备的,缺陷较多因而激子浓度低,其紫峰较弱.随着制备时氧流量的增加,薄膜中的缺陷有所减少,激子浓度也随之增加,使得紫峰的强度上升.样品B和C的氧流量比样品A 低,它们的氧原子和锌原子的个数比会比样品A更加偏离标准化学计量比,从而可能导致样品B和C 中发光带尾的存在[14,15].带2带复合和自由激子复合的发光中心也分别从带边态移向带尾态,使近紫外光和紫光的发光能隙变小,波长变长.绿峰的峰值能量为214eV,远小于ZnO的禁带宽度313eV,它应该与本征缺陷位于禁带中的局域态有关.在ZnO薄膜中氧空位构成施主能级,锌空位构成受主能级,绿峰应该来自施主和受主能级之间的跃迁.在低氧流量下制备的样品C中含有较多的氧空位缺陷,它的P L 光谱有明显的绿峰,当增加氧流量后会使得氧空位缺陷减少,锌空位缺陷增加,施主和受主能级之间的跃迁受到抑制,从而使制备的样品A和B的绿峰消失.但是由导带底到受主能级之间的跃迁会得到增强,它们的能量差约为216eV,形成了强的蓝光带发射.使用ZnO靶溅射沉积薄膜时,锌和氧原子的溅射率不同,一般而言,锌原子的溅射率高于氧原子的溅射率.因而在纯氩气氛中溅射沉积的ZnO薄膜往往缺氧.也就是存在氧空位等缺陷.当在源气体中适当添加氧气后,可促进薄膜的氧化,从而降低氧缺陷浓度,使薄膜从缺氧状态转化为标准化学计量比状态.当加入过量氧气后,又可能导致锌缺陷浓度增加[12].从上述关于不同氧流量下制备的ZnO薄膜P L 峰位和峰强的演变分析,表明ZnO薄膜的P L特性确实受到氧缺陷或者锌缺陷等本征缺陷的影响.在低氧流量下制备的缺氧薄膜的P L谱图存在峰值波长位于510nm左右的绿光带,这主要是由于薄膜中有大量的氧缺陷存在.随着氧流量的增加,氧缺陷浓度逐渐降低,由于氧缺陷而产生的绿光带的强度会降低直到消失,同时可能使薄膜中锌缺陷的浓度增加,从而在样品B和C的P L光谱中出现峰值波长位于470nm左右的蓝光带.图2　改变源气体制备的ZnO薄膜的P L光谱　谱线M源气体为氩气,谱线N源气体为氧气为了进一步验证上述的分析,我们分别在纯氩环境下和纯氧环境下制备了样品M和N.图2为M 和N两块样品的P L光谱.缺氧环境下制备的样品868物理学报53卷M 的P L 光谱具有类似于样品C 的特征,它有三个分离的发光带:近紫外光带、紫光带和绿光带,且紫光占优势.而富氧环境下制备的样品N 的P L 光谱则与样品A 和B 类似,除近紫外光带和紫光带,还有一个强的蓝光带.图3　不同温度下真空退火后处理的ZnO 薄膜的P L 光谱　谱线a 为未退火,谱线b 为150℃退火,谱线c 为300℃退火,谱线d 为450℃退火为了进一步验证本征缺陷对发光中心的影响,我们对ZnO 薄膜作了真空后处理.图3给出没有后处理的样品a 和经过真空加热后处理的样品b ,c 和d 的P L 光谱图,样品b ,c 和d 的退火温度分别为150,300和450℃.样品a 的P L 光谱主要有三个主要的发光带:峰值波长分别位于375,400,470nm 的近紫外发光带、紫光带和蓝光带.样品b 的P L 光谱与样品a 的P L 光谱很类似,这表明经过150℃低温后处理没有改变薄膜中的缺陷分布,但是在较高温度下处理过的样品c 和d 的P L 光谱发生了明显的变化:近紫外峰和紫峰变得尖锐.这是由于加热后处理使得薄膜的结晶状态得到了明显的改善.图4给出4个样品的XRD 谱图.从图4可见,经过后处理的样品c ,d 的(002)峰变得高而尖锐,(100),(101)峰变弱,这表明加热后处理使得ZnO 薄膜的择优取向变强,结晶状态得到改善,它有利于促图4　不同温度下真空退火后处理的ZnO 薄膜XRD 谱图　谱线a 为未退火,谱线b 为150℃退火,谱线c 为300℃退火,谱线d 为450℃退火进带—带跃迁和激子复合的发生.图3中另外一个值得关注的是后处理使得蓝峰明显地向长波方向移动,变成了绿峰.它的发光特性类似于上面叙述的在低氧流量下制备的样品c .这表明,在缺氧环境下的加热后处理使薄膜中增加了氧和锌的本位缺陷能级之间的跃迁.这主要是由于样品在真空下退火,随着退火温度的增加,ZnO 薄膜中的氧原子可能逃逸,从而使ZnO 薄膜中的氧缺陷浓度升高.41结论本文使用射频磁控溅射法制备了ZnO 薄膜,通过改变源气体中Ar ΠO 2流量比以及加热后处理来改变ZnO 薄膜中氧缺陷和锌缺陷浓度,研究了它们对ZnO 薄膜P L 特性的影响.结果显示,在高氧流量下制备的ZnO 薄膜的P L 光谱主要是峰值波长分别位于400,470nm 的强的紫光带和蓝光带.在低氧流量下制备的ZnO 薄膜,以及在纯氧环境下制备的薄膜经过300和450℃的真空后处理以后,其P L 光谱主要是峰值波长分别位于420,510nm 的强的紫光带和较弱的绿光带.通过调制薄膜中氧和锌的本征缺陷的浓度以及结晶状态,可以获得发出蓝光或绿光的ZnO 薄膜.[1]Lin B X ,Fu Z X ,Jia Y B and Liao G H 2001Acta Phys .Sin .502208(in Chinese )[林碧霞、傅竹西、贾云波、廖桂红2001物理学报502208][2]Lin B X ,Fu Z X ,Jia Y B and Liao G H 2001Chin .J .Luminescence 22167(in Chinese )[林碧霞、傅竹西、贾云波、廖桂红2001发光学报22167]9683期李伙全等:射频磁控溅射沉积的ZnO 薄膜的光致发光中心与漂移[3]Shi C S,Fu Z X,G uo C X,Y e X L,W ei Y G,Deng J,Shi J Y andZhang G B1999J.Electron.Spectros.Related Phenom.1012103629[4]Zhang Y T,Du G T,Liu D L,W ang X Q,M a Y,W ang J Z,Y in JZ,Y ang X T,H ou X K and Y ang S R2002J.Cryst.Growth243439[5]Chen S J,Liu Y C,M a J G,Zhao D X,Zhi Z Z,Lu YM,ZhangJ Y,Shen D Z and Fan X W2002J.Cryst.Growth240467 [6]Xu X L,G uo C X,Qi Z M,Liu H T,Xu J,Shi C S,Chong C,Huang W H,Zhou YJ and Xu C M2002Chem.Phys.Lett.36457[7]Fu Z X,Lin B X,Liao G H and Wu Z Q1998J.Cryst.Crowth193316[8]Lu Y M,H wang W S,Liu W Y and Y ang J S2001Mater.Chem.Phys.72269[9]Xue Z Y,Zhang D H,W ang Q P and W ang J H2002Appl.Sur f.Sci.195126[10]M itra A and T areja P K2001J.Appl.Phys.892025[11]Wu H Z,Qiu D J,Cai YJ,Xu XL and Chen N B2002J.Cryst.Growth24550[12]K ohan A F,Ceder G and M organ D2000Phys.Rev.B6115019[13]Lyu S C,Zhang Y,Ruh H,Lee HJ,Shim H W,Suh E Kand LeeC J2002Chem.Phys.Lett.363134[14]Xu X L,Lau S P,Chen J S,Chen G Y and T ay B K2001J.Cryst.Growth223201[15]Xu X L,Lau S P,Chen J S,Sun Z,T ay B K and Chai J W2001Mater.Sci.Semicond.Proc.4617[16]Y ang X J,Shi C S and Xu X L2002Acta Phys.Sin.512871(inChinese)[杨秀健、施朝淑、许小亮2002物理学报512871] [17]Sun X,X iong G,Fu Z X and Wu Z Q2000Acta Phys.Sin.49855(in Chinese)[孙　霞、熊　刚、傅竹西、吴自勤2000物理学报49855][18]Liu S M,Liu F Q,Zhang Z H,G uo H Q and W ang Z G2000ActaPhys.Sin.492307(in Chinese)[刘舒曼、刘峰奇、张志华、郭海清、王占国2000物理学报492307]Photolumine scence centers and shift of ZnO films depo sitedby rf magnetron sputteringLi Huo2Quan　Ning Zhao2Y uan　Cheng Shan2Hua　Jiang M ei2Fu(School o f Physical Science and Technology,K ey Laboratory o f Film Materials,Jiangsu Province,Suzhou　215006,China)(Received15April2003;revised manuscript received2June2003)AbstractZnO films deposited by rf magnetron sputtering with different stoichimetries were made by varing ArΠO2flow rate during the depositions,and annealed in vacuum.The photolum inescence measurements show that the films have strong blue em ission.As O2gas flow decreases,the blue em ission peak m oves to long wavelength side.The blue em ission may correspond to the electron transition from the bottom of the conduction band to the acceptor level com posed of zinc defects.K eyw ords:ZnO fims,photolum inescence,annealing,blue em issionPACC:6800,7855,8140G078物理学报53卷。

氧化锌薄膜的微观结构及其结晶性能研究

氧化锌薄膜的微观结构及其结晶性能研究陈首部;陆轴;兰椿【摘要】以普通玻璃作为衬底材料,采用射频磁控溅射方法制备了氧化锌(ZnO)透明导电薄膜,通过X射线衍射(XRD)和X射线光电子能谱(XPS)测试,研究了衬底温度对薄膜微观结构及其结晶性能的影响.结果表明:所制备的ZnO薄膜均为(002)晶面择优取向生长的多晶薄膜,其微观结构和结晶性能与衬底温度密切相关.衬底温度对ZnO薄膜的织构系数TC(hkl)、平均晶粒尺寸、位错密度、晶格应变和晶格常数都具有不同程度的影响,当衬底温度为800 K时,ZnO薄膜样品的织构系数TC(002)最高(4.929)、平均晶粒尺寸最大(20.91 nm)、位错密度最小(2.289×1015 line·m-2)、晶格应变最低(2.781×10-3),具有最高的(002)晶面择优取向生长性和最佳的微观结构性能.%The transparent conducting oxide thin films of zinc oxide ( ZnO) were deposited on glass substrates by radio-frequency magnetron sputtering method . The influence of substrate temperature on the mirostructure and crystalline characteristics of ZnO thin films was investigated by X-ray diffraction ( XRD ) and X-ray photoelectron spectroscopy ( XPS ) , respectively . The results indicate that the deposited thin films with the hexagonal crystal structure are polycrystalline and have a strongly preferred orientation of (002) plane.The mirostructure and crystalline characteristics of the thin films are observed to be subjected to the substrate temperature .When the substrate temperature is 800 K, the deposited ZnO sample exhibits the best crystalline and microstructural properties , with the highest texture coefficient of (002) plane of 4.929, the largest average grain size of 20.91nm, t he minimum dislocation density of 2.289 ×1015 line· m-2 and the lowest lattice strain of 2.781 ×10 -3 .【期刊名称】《中南民族大学学报（自然科学版）》【年(卷),期】2017(036)004【总页数】6页(P67-72)【关键词】氧化锌;薄膜;微观结构;结晶性能【作者】陈首部;陆轴;兰椿【作者单位】中南民族大学电子信息工程学院,武汉430074;中南民族大学电子信息工程学院,武汉430074;中南民族大学电子信息工程学院,武汉430074【正文语种】中文【中图分类】TM914作为第三代新型半导体材料的主要代表之一，氧化锌(ZnO)不仅自然储量丰富、价格低廉、绿色环保，同时还具有优异的光电、光敏、压电和压敏等性质.它与硫化锌(ZnS)和氮化镓(GaN)相比，ZnO在室温条件下具有较宽的直接带隙和较高的自由激子结合能，是制备光电功能器件的优良材料，已被广泛应用于太阳能电池[1-5]、发光显示器[6-11]、半导体激光器[12]、紫外探测器[13]、声表面波器件[14]以及触摸控制面板[15]等领域具有广阔的应用前景.目前，制备ZnO薄膜的方法多种多样，如水热法[16]、溶胶-凝胶法[17]、化学气相沉积法[18]、原子层沉积法[19]、脉冲激光沉积法[20]、喷雾热分解法[21]和磁控溅射法[22-25]等，其中磁控溅射技术具有工艺简单、成膜均匀、致密性好、成本低廉、易于大面积制备等优点，因此得到了业界的广泛应用.ZnO薄膜的晶体质量及其性能与其制备工艺参数密切相关，其中影响较大的工艺因素有衬底温度、溅射功率和工作压强等，因此深入研究溅射工艺参数对ZnO薄膜微观结构的影响具有十分重要的意义.本文以普通玻璃作为衬底材料，采用射频磁控溅射方法制备ZnO薄膜样品，通过X射线衍射(XRD)和X射线光电子能谱(XPS)测试表征，研究了衬底温度对ZnO薄膜微观结构及其结晶性能的影响.采用普通玻璃作为衬底材料，切割成大小为30 mm×30 mm的方块，实验时按照如下程序对玻璃衬底进行处理：(1)采用丙酮擦拭衬底表面，并用清水冲洗干净；(2)依次使用丙酮、无水乙醇和纯净水对衬底进行超声清洗13 min，以去除衬底表面的微粒和有机污染物；(3)在无水乙醇中煮沸，吹干待用.利用射频磁控溅射方法在玻璃衬底上制备ZnO薄膜样品，所用实验设备为KDJ-567型高真空复合镀膜系统，溅射源为直径50 mm、厚度4 mm的ZnO陶瓷靶材，它以ZnO粉体(999.99%)为原料通过常压固相烧结工艺制成.溅射制备ZnO 薄膜样品之前，将溅射室的真空度抽至5×10-4 Pa后通入99.999%的高纯氩气作为工作气体，并先采用氩等离子体对玻璃衬底表面清洗7 min，然后再预溅射10 min以清洁靶材表面和稳定系统，提高沉积ZnO薄膜样品的质量.实验时，衬底与靶材之间的距离为75 mm、溅射功率为200 W、工作气压为0.5 Pa、沉积时间为25 min、衬底温度为600～800 K.通过X射线衍射仪(Bruker advance D8型，德国Bruker公司)对ZnO薄膜样品进行晶体结构表征，测试时使用Cu Kα射线源(波长λ=0.1541 nm)，采用θ-2θ连续扫描方式，扫描速度为10°/min，扫描步长为0.0164 Å，扫描范围为20°≤2θ≤70°，工作电压为40 kV，工作电流为40 mA.利用X射线光电子能谱仪(VG Multilab 2000型，美国Thermo Electron公司)对ZnO薄膜样品进行XPS 分析，测试时本底真空度为2.0×10-6 Pa，X射线源为单色Al Kα射线源(hv=1486.60 eV)，采用C 1s结合能(284.60 eV)作为内标，对所有测试谱峰进行荷电校正.所的测试均在室温条件下完成.图1为不同衬底温度时ZnO薄膜样品的XRD图谱，由图可见，在2θ为20 °～70°的扫描范围内，所有ZnO薄膜样品在峰位2θ为30.9°和34.1°附近都出现了2个特征峰，比对ZnO的标准PDF卡片(JCPDS #36-1451，见图1)可以看出，这2个衍射峰分别与ZnO的(100)和(002)晶向相吻合.另外从图1中还可看到，衬底温度不同时，ZnO薄膜样品还存在有其它晶向的特征峰，如衬底温度为600和800 K时，分别显示有(110)和(103)晶面的衍射峰，而衬底温度为700 K时，则显示有(110)、(102)和(103)等多个晶面的衍射峰.上述XRD图谱结果表明，所制备的ZnO样品均为多晶薄膜，并具有六角纤锌矿结构.观察图1的XRD图谱还可以看出，衬底温度对衍射峰位2θ的影响较小，而对各个晶向的衍射峰强度的影响较大，为了评估ZnO薄膜样品沿某一晶面(hkl)的择优取向程度，本文采用织构系数(TC(hkl))来定量表征样品沿不同晶面生长的取向程度.织构系数TC(hkl)定义如下[26]：(1)式中，下标h、k、l表示密勒指数，TC(hkl)表示(hkl)晶面的织构系数，I(hkl)为ZnO薄膜样品在(hkl)晶面的衍射强度，Ir(hkl)为标准ZnO粉未试样(JCPDS #36-1451)在(hkl)晶面的衍射强度，n为计算时所取的衍射峰数目.TC(hkl)的数值越大，说明薄膜中有更多的晶粒沿(hkl)晶面生长，即薄膜在(hkl)晶面的择优取向性越好.表1列出了不同衬底温度时ZnO薄膜样品的织构系数TC(hkl)，由表1可见，当衬底温度为600、700和800 K时，ZnO薄膜样品的TC(002)值分别为4.916、4.363和4.929，均远远高于其它晶面的TC(hkl)数值，这说明所制备的ZnO样品都表现出明显的(002)晶面择优取向生长特征，并且衬底温度升高时，TC(002)的数值呈现出先减小后增大的变化趋势.可见，衬底温度从600 K增加到800 K时，虽然没有改变ZnO薄膜(002)择优取向生长特征，但是对其择优取向程度有一定的影响，当衬底温度为800 K时所制备的ZnO样品具有最高的(002)择优取向程度.其原因是：ZnO薄膜在(002)晶面的表面自由能密度是最小的，因此晶粒沿(002)晶面具有生长优势，在生长过程中晶粒极易沿c轴即(002)晶面平行于衬底的方向生长[27,28].图2为衬底温度800 K时所制备ZnO薄膜样品的XPS能谱图，由图2可见，XPS图谱上除了Zn和O原子的光电子特征峰之外，在284.6 eV处还存在有C1s特征峰，这可能是由于溅射镀膜时油扩散泵污染或者ZnO薄膜样品暴露在大气中吸附了CO2所造成的[29].图3(a)为不同衬底温度时ZnO薄膜样品的(002)衍射峰半高宽(B)数值，可见半高宽B的值与衬底温度密切相关，衬底温度增加时，半高宽B单调减小，当衬底温度为800 K时，ZnO薄膜样品(002)衍射峰的半高宽B最小值为0.392°，说明衬底温度为800 K时制备的ZnO薄膜样品具有最大的晶粒尺寸和最佳的结晶性能.ZnO薄膜样品的平均晶粒尺寸(D)可以根据谢乐公式[30]计算：(2)式中，K为谢乐常数(这里取K=0.89)，θ为所(002)晶面的布拉格角，B为(002)衍射峰的半高宽数值，λ为XRD测试时的X射线波长[31].图3(b)为不同衬底温度时ZnO薄膜样品的平均晶粒尺寸D，从图中3(b)看出，衬底温度对ZnO样品的平均晶粒尺寸D具有明显的影响.当衬底温度为600～800 K时，ZnO样品的平均晶粒尺寸D为9.73～20.91 nm，平均晶粒尺寸D随衬底温度增加而增大，当衬底温度为800 K时，ZnO薄膜样品的D值最大(20.91 nm).ZnO薄膜样品的位错密度(δ)[31]利用公式(3)计算获得：(3)式中，D为ZnO薄膜样品的平均晶粒尺寸.ZnO薄膜样品的位错密度δ随衬底温度变化的曲线如图4所示，可以看出，随着衬底温度的增加，δ呈现出单调减小的变化趋势，当衬底温度为800 K时，ZnO薄膜样品的位错密度δ最小为2.289×1015 line·m-2.ZnO薄膜样品的晶格应变(ε)可由下式[32]计算：(4)式中，K为由谢乐常数，θ为所(002)晶面的布拉格角，B为(002)衍射峰的半高宽数值.不同衬底温度时ZnO薄膜样品的ε值如图5所示，从图5看出，衬底温度对ZnO薄膜ε值具有明显的影响，ε值随着衬底温度的增加而逐渐减小，当衬底温度为800 K时，ZnO薄膜样品具有最小的晶格应变ε，其值为2.781×10-3. ZnO薄膜样品为六角纤锌矿结构，其晶格常数由公式(5)确定[33,34]：(5)式中，a和c为ZnO样品的晶格常数.对于(002)晶面，由(5)式可得：对于(100)晶面，(5)式可简化为：图6为不同衬底温度时ZnO薄膜样品的晶格常数a、c和c/a的数值，从图6看出，衬底温度增大时，a先减后增、c单调增加、c/a先增后减，在衬底温度的变化范围为600～800 K时，a、c和c/a的数值范围分别为0.32845～0.33608 nm、0.52259～0.52857 nm和1.57275～1.59411，这些结果与标准ZnO试样(JCPDS #36-1451)数据(a=0.32498 nm、c=0.52066 nm、c/a=1.60213)是一致的.文献[35,36]在研究掺钇ZnO和掺锂ZnO薄膜时也有类似的报道.ZnO薄膜样品的Zn-O键长(L)[37]可由公式(8)计算获得：(8)式中，a和c为ZnO薄膜样品的晶格常数，u与a、c之间满足关系式[37]：图7为ZnO样品薄膜Zn-O键长L随衬底温度的变化曲线，从图可知，衬底温度对ZnO薄膜的Zn-O键长L具有一定的影响，当衬底温度为600、700和800 K 时，ZnO样品的Zn-O键长L值分别为0.2002、0.19957和0.20337 nm，其结果与标准ZnO试样(JCPDS No. 36-1451)数据(L=0.19778 nm)基本一致.Anandan等人[35]和Srinivasan小组[36]在研究掺杂ZnO薄膜时也报道过类似的结果.采用ZnO陶瓷靶为溅射源材料，利用射频磁控溅射技术在普通玻璃衬底上制备了ZnO薄膜样品，通过XRD和XPS测试表征，研究了衬底温度对ZnO薄膜样品微观结构及其结晶性能的影响.结果表明，所有ZnO薄膜样品均为六角纤锌矿结构的多晶薄膜，并且衬底温度对薄膜生长特性及其微观结构性能具有明显的影响.衬底温度升高时，ZnO薄膜的织构系数TC(002)、晶格常数a和Zn-O键长L先减后增，平均晶粒尺寸D和晶格常数c单调增加，而位错密度δ和晶格应变ε则单调减小，当衬底温度为800 K时，ZnO薄膜样品的织构系数TC(002)最高为4.929、平均晶粒尺寸D最大为20.91 nm、位错密度δ最小为2.289×1015 line·m-2、晶格应变δ最低为2.781×10-3，所制备的ZnO薄膜具有最高的(002)晶面择优取向生长性和最好的微观结构性能.【相关文献】[1] Liu H, Avrutin V, Izyumskaya N, et al. 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溅射氩气压对射频磁控溅射制备 ZnO∶Al 薄膜性能的影响

溅射氩气压对射频磁控溅射制备ZnO∶Al 薄膜性能的影响刘超英;陈玮;徐志伟;付静;左岩;马眷荣【摘要】采用磁控溅射方法在玻璃衬底上使用掺杂3％(质量分数)Al2 O 3的 ZnO 陶瓷靶材制备出了掺铝氧化锌(ZnO ∶ Al,AZO)透明导电薄膜.分别用XRD、SEM、四探针测试仪、紫外-可见分光光度计对薄膜的性能进行了表征和分析.研究了溅射过程中不同氩气压强(0．3~1．2 Pa)对薄膜结构、形貌及光电性能的影响.XRD 测试结果表明,所制备的薄膜均具有呈c 轴择优取向的纤锌矿结构.当氩气压强为0．3 Pa时,AZO 薄膜的电阻率最低为6．72×10－4Ω•cm.所有样品在可见光波段的平均透过率超过85％.%Transparent conductive aluminum-doped zinc oxide (AZO)films were deposited on glass substrates by RF magnetron sputtering from ZnO∶3wt% Al2 O 3 ceramic target.The films obtained we re characterized and analyzed by XRD,SEM,four-point probes,ultraviolet-visible light spectrophotometer.The dependence of ar-gon gas pressure on the structure,morphology,electrical and optical properties were investigated.The argon sputtering pressure was varied between 0.3 and 1.2 Pa.The XRD analysis indicated that AZO films deposited under various argon gas pressures were a polycrystalline wurtzite structure with a [002]preferred orientation. The lowest resistivity was 6.7×10 -4 Ω•cm (sheet resistance=1 1.2 Ω/□ for a thickness=600 nm)which was obtained at an argon sputtering pressure of 0.3 Pa.The average transmittance was over 85% in the visible range for all samples.【期刊名称】《功能材料》【年(卷),期】2015(000)007【总页数】4页(P7052-7055)【关键词】氩气压力;射频磁控溅射;AZO 薄膜;光电性能【作者】刘超英;陈玮;徐志伟;付静;左岩;马眷荣【作者单位】中国建筑材料科学研究总院，北京 100024; 国家玻璃深加工工程技术中心，北京 100024; 绿色建筑材料国家重点实验室，北京 100024;中国建筑材料科学研究总院，北京 100024; 国家玻璃深加工工程技术中心，北京 100024;中国建筑材料科学研究总院，北京 100024; 国家玻璃深加工工程技术中心，北京100024;中国建筑材料科学研究总院，北京 100024; 绿色建筑材料国家重点实验室，北京 100024;中国建筑材料科学研究总院，北京 100024; 国家玻璃深加工工程技术中心，北京 100024;中国建筑材料科学研究总院，北京 100024【正文语种】中文【中图分类】TB341 引言透明导电薄膜是一种重要的半导体光电材料，具有高电导率的同时具备高的可见光区透过率，广泛地应用于平面显示、太阳能电池、特殊功能窗口涂层、气体传感器及其它光电、热电器件领域［1－4］。

脉冲激光沉积

7
PLD的优点
• (1) 采用高光子能量和高能量密度的紫外脉冲激光作为产生等离子体的能源，因而无污染又易于控制 • (2) 烧蚀物粒子能量高，可精确控制化学计量，实现靶膜成分接近一致，简化了控制膜组分的工作，特别适合制备具有复杂成分和高熔点的薄膜 • (3) 生长过程中可原位引入多种气体，可以在反应气氛中制膜，这为控制薄膜组分提供了另一条途径 • (4) 多靶材组件变换灵便，容易制备多层膜及异质结 • (5) 工艺简单，灵活性大，可制备的薄膜种类多 • (6) 可用激光对薄膜进行多种处理等
脉冲宽度图5-6 等离子体羽辉外形随时间的演化激光作用结束后
激光作用时间图5-7 等离子体膨胀过程中间的输运
靶材表面的高温(可达20000K)和高密度((1016--1021)/cm3)的等离子体在靶面法线方向的高温和压力梯度
等温膨胀发射(激光作用时)和绝热膨胀发射(激光终止后)
8
待解决的问题
• (1) 不易于制备大面积的膜。 • (2) 在薄膜表面存在微米-亚微米尺度的颗粒物污染，所制备薄膜的均匀性较差。 • (3) 某些材料靶膜成分并不一致。对于多组元化合物薄膜，如果某些种阳离子具有较高的蒸气压，则在高温下无法保证薄膜的等化学计量比生长。
9
5.2 PLD的基本原理
抽真空（机械泵与分子泵至10-5Pa）
开加热装臵，通气体导入激光进行镀膜关闭仪器
23
The end
• 使用高致密度的靶材，同时选用靶材吸收高的激光波长。
因为液滴产生的情况在激光渗入靶材越深时越严重。靶材对激光的吸收系数越大，则作为液滴喷射源的熔融层越薄，产生的液滴密度越低。
• 通过基于速率不同的机械屏蔽技术来减少颗粒物（由于 PLD产生的颗粒物的速率要比原子、分子的速率低一个数量级）。

透明导电薄膜的研究现状及应用

透明导电薄膜的研究现状及应用摘要：综述了当前透明导电薄膜的最新研究和应用状况，重点讨论了ITO膜的光电性能和当前的研究焦点。

指出了目前需要进一步从材料选择、工艺参数制定、多层膜光学设计等方面来提高透明导电膜的综合性能，使其可见光平均透光率达到92%以上，从而满足高尖端技术的需要。

关键词：透明导电，薄膜，平均透光率，ITO，电导率透明导电薄膜的种类有很多，但氧化物膜占主导地位（例如ＩＴＯ和ＡＺＯ膜）。

氧化铟锡（ＩｎｄｉｕｍＴｉｎＯｘｉｄｅ简称为ＩＴＯ）薄膜、氧化锌铝（Ａｌ－ｄｏｐｅｄＺｎＯ，简称ＡＺＯ）膜都是重掺杂、高简并ｎ型半导体。

就电学和光学性能而言，它是具有实际应用价值的透明导电薄膜。

金属氧化物透明导电薄膜（ＴＣＯ：ＴｒａｎｓｐａｒｅｎｔａｎｄＣｏｎｄｕｃｔｉｖｅＯｘｉｄｅ的缩写）的研究比较早，Ｂａｋｄｅｋｅｒ于１９０７年第一个报道了ＣｄＯ透明导电薄膜。

从此人们就对透明导电薄膜产生了浓厚的兴趣，因为从物理学角度看，透明导电薄膜把物质的透明性和导电性这一矛盾两面统一起来了。

１９５０年前后出现了硬度高、化学稳定的ＳｎＯ２基和综合光电性能优良的Ｉｎ２Ｏ３基薄膜，并制备出最早有应用价值的透明导电膜ＮＥＳＡ（商品名）－ＳｎＯ２薄膜。

ＺｎＯ基薄膜在２０世纪８０年代开始研究得火热。

ＴＣＯ薄膜为晶粒尺寸数百纳米的多晶；晶粒取向单一，目前研究较多的是ＩＴＯ、ＦＴＯ（Ｓｎ２Ｏ：Ｆ）。

１９８５年，ＴａｋｅａＯｊｉｏＳｉｚｏＭｉｙａｔａ首次用汽相聚合方法合成了导电的ＰＰＹ－ＰＶＡ复合膜，从而开创了导电高分子的光电领域，更重要的是他们使透明导电膜由传统的无机材料向加工性能较好的有机材料方面发展。

透明导电膜以其接近金属的导电率、可见光范围内的高透射比、红外高反射比以及其半导体特性，广泛地应用于太阳能电池、显示器、气敏元件、抗静电涂层以及半导体／绝缘体／半导体（ＳＩＳ）异质结、现代战机和巡航导弹的窗口等。

由于ＩＴＯ薄膜材料具有优异的光电特性，因而近年来得以迅速发展，特别是在薄膜晶体管（ＴＦＴ）制造、平板液晶显示（ＬＣＤ）、太阳电池透明电极以及红外辐射反射镜涂层、火车飞机用玻璃除霜、建筑物幕墙玻璃等方面获得广泛应用，形成一定市场规模。

薄膜厚度及折射率的计算方法

The optical constants and thickness evaluated by ‘‘Refractor’’ for Pr3+-doped (2000 ppm) chalcogenide thin ﬁlms, grown on microscope slabs and glass slides by PLD, are reported.
0169-4332/$ – see front matter # 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.apsusc.2005.03.069
A.P. Caricato et al. / Applied Surface Science 248 (2005) 440–445
T ¼ Tðn; xÞ:
For k2 ( n2, the expression for the transmittance can be written [7]:
Ax
TðlÞ ¼ B À Cx cos ’ þ Dx2
(2)
where A = 16n2s; B = (n + 1)3(n + s2); C = 2(n2 À 1) (n2 À s2); D = (n À 1)3(n À s2); w = 4pnd/l.
Since À1 cos w 1, T(l) values can vary
between
Tm
¼
Ax BþCxþDx2
and
TM
¼
Ax BÀCxþDx2
.
A typical transmission spectrum at normal inci-
‘‘Refractor’’ has several advantages: (1) it gives accurate results in a short time and reduces the number of arithmetic operations needed to compute n, k and d as compared to other computer techniques [1–4]; (2) it takes into account possible inhomogeneities in the ﬁlm thickness; (3) it is not based on minimisation techniques as other commercial software; (4) using the obtained n, k and d values, the simulated spectrum as well as the experimental one can be graphically compared.

掠射和θ-2θ方式X射线衍射分析In掺杂ZnO薄膜结构特性

掠射和θ-2θ⽅式X射线衍射分析In掺杂ZnO薄膜结构特性/doc/2bbee4c72cc58bd63186bddf.html Structural properties of In-doped ZnO thin films analyzed by x-ray diffraction at grazing incidence and θ-2θ geometryWei Lan, Xueqin Liu, Chunming Huang, Defeng Guo, Yinyue Wang﹡Department of Physics, School of Physical Science and Technology, Lanzhou University,Lanzhou 730000, P. R. ChinaAbstractIn-doped ZnO thin films were successfully deposited on quartz substrates by sol-gel spin-coating technique. The structural properties of these films were investigated by x-ray diffraction at grazing incidence (GI-XRD) and conventional θ-2θgeometry (C-XRD). It is found that (002) and (103) diffraction peaks are predominant in the GI-XRD patterns (incidence angleα=1°), and when above the critical In doping concentration (～2 at.%), which is related to the solid solubility, the (103) peak gradually becomes the main growth orientation instead of the (002) peak. However, all the thin films only have a preferred (002) orientation in the C-XRD patterns, and the concerned (103) peak doesn’t appear. The doping concentration of 1 at.% is proved to be optimum for In-doped ZnO thin films. Based on the different penetration depths of x-rays between two scattering geometries, it is suggested that the ZnO thin films have different crystal structures at the surface and in the bulk. The increase of the (002) peak and the decrease of the (103) peak atα=5° in the GI-XRD patterns are apparent evidences of structure transition from the surface to the bulk.PACS: 61.10.N; 78.66.H; 61.72; 61.43.DKeywords: Grazing incidence x-ray diffraction; In-doped ZnO thin films; Crystal structure; Sol-gel﹡Corresponding author: Fax: +86-931-891-3554. E-mail address:wangyy@/doc/2bbee4c72cc58bd63186bddf.html (Y. Wang).1. IntroductionZinc oxide (ZnO) has been deeply studied as a direct wide bandgap oxide semiconductor (Eg=3.37eV) for its potential utilization in short wavelength light-emitting/detecting devices. It has non-toxicity, high chemical and thermal stability, large mechanical strength and high exciton binding energy (60 meV at room temperature) and that makes it an ideal material for developing room temperature excitonic devices. The hexagonal lattice constants of ZnO are close to those of GaN with the lattice mismatch of 2.2% between them so that it has been proposed as buffer layer for the growth of GaN [1]. In addition, ZnO can also be used for transparent conducting oxide electrodes in flat panel displays, solar cells, gas sensor and surface acoustic wave devices. For a wide bandgap semiconductor, the addition of impurity often induces dramatic changes in its electrical and optical properties [2], and In-doped ZnO thin films also accord with this rule. The resistance obtained from In-doped ZnO thin films was generally 10-3Ωcm [3], which decreases three orders of magnitude compared to the undoped films. It has been investigated and found that the optical bandgap of In-doped ZnO thin films showed an abrupt jump from blueshift to redshift [4]. Besides, microstructure changes of In-doped ZnO thin films should be paid more attention. Many reports [5,6] have indicated the doping effects of In on structural properties of ZnO thin films. These films were generally polycrystalline according to the analyzing results of x-ray diffraction at θ-2θ geometry (C-XRD) or grazing incidence (GI-XRD), and structural properties of them changed dramatically with the increase of In concentration. Therefore, there is an urgent need for a further investigation and improvement in microstructure properties. To learn more about this structural characteristic we used GI-XRD and C-XRD simultaneously at the same instrument. Little work with such methods has been done in the research field of the crystalline structure of ZnO thin films.Until now, ZnO thin films have been prepared by various methods, such as molecular beam epitaxy [7], pulsed laser deposition [8], metal organic chemical vapor deposition [9], sputtering [10], ultrasonic spray pyrolysis [11] and sol-gel [12]. In contrast, sol-gel technique is simple and has low cost, large area deposition and controllability of compositions, and the other important advantage is out of the limitation of vacuum system.In this paper, In-doped ZnO thin films with different dopant concentrations (varying in the 0-5 at.% range) were prepared on quartz substrates by sol-gel spin-coating technique. The doping effects of In on the structural properties of ZnO thin films were observed and discussed.2. Experimental procedureIn-doped ZnO thin films were prepared by the sol-gel spin-coating technique. As a starting material, zinc acetate dihydrate (Zn(CH3COO)2·2H2O) was dissolved in the solvent 2-methoxyethanol (MOE, CH3OCH2CH2OH) at room temperature.Addition of monoethanolamine (MEA, NH2CH2CH2OH) was found necessary because it imparts sol stability for an extended period of time. The molar ratio of [Zn2+]/MOE/MEA was 1:17:1 in the resulting solution. Indium nitrate (In(NO3)3) solution was used as the dopant source of indium and dissolved in the mixed solution described above, in which the molar ratio of [In3+]/[Zn2+] varied from 0 to 5 at.%. The solution was stirred vigorously at 60℃for 2h with reflux to yield a clear and homogenous precursor solution, which served as the coating solution after cooling to room temperature. The coating was usually made 2 days after the solution was prepared so as to increase the viscosity of the solutions. Quartz and Si substrates were used to deposit In-doped ZnO thin films. Prior to thin film deposition, the substrates were ultrasonically cleaned in a series of organic solvents followed by absolute alcohol.The precursor solutions were spin-coated onto the substrates with a dimension 2×2 cm2 at a rotating speed of 3000 rpm for 20s. After deposited by spin-coating, the precursor films were put into preheated furnace and heated at 350℃for 10 min to evaporate the solvent and remove organics. Finally, all films were annealed for 1h in air at 600℃, which was the optimum annealing temperature as testified by our experiments. The In-doped ZnO thin films prepared were free from any cracks, voids etc.Infrared reflection spectra were carried out on the In-doped ZnO thin films as-deposited, preheated and annealed, by the Fourier transform infrared spectrometer (NEXUS 670) in the 400-4000 cm-1 region. The structures of all ZnO thin films were confirmed by x-ray diffractionometer (Philips X’per pro MPD, 45 kV, 40 mA) employing Cu Kαradiation with λ=1.5405? at both grazing incidence (asymmetric alignment with different incidence angles) and conventional θ-2θ geometry. The grain size of ZnO was calculated by the Scherrer’s equation, D=0.90λ/(W·cosθ), Where λ, θ and W are the x-ray wavelength, Bragg diffraction angle and the full width at half maximum (FWHM) of the diffraction peak, respectively. The ZnO thin films on Si substrates were only used to measure the thickness, which was analyzed by an ellipsometer (Gaertner Scientific Corporation L116E). All the measurements were performed in air at room temperature.3. Results and discussionIn order to clearly understand the decomposition degree of the precursor films, In-doped ZnO thin film with 3 at.% concentration was tested by Fourier transform infrared spectrometer (FTIR). Figure 1 shows the FTIR reflection spectra of the thin film and a bare quartz substrate forcomparison. Solid curve represents the reflection spectrum of the as-deposited film. Except that the narrow band in the range of 1020-1090 cm-1 and the peak at about 804 cm-1 are due to the different vibrations of the substrate SiO2, other peaks and bands on the curve are all corresponding to organic compounds of the precursor film. A broad band between 2800 and 3600 cm-1 and a small peak (1339 cm-1) are attributed to the different vibrations of the –OH and/or –NH2 groups of the solvent and stabilizer (MOE and MEA) [13], and a little water also contributes to the broad band. The two most characteristic peaks located at 1571 and 1413 cm-1 are associated with asymmetric and symmetric stretching vibrations of COO- group of zinc acetate [14]. After the film is preheated at 350℃ for 10 min, all absorption peaks corresponding to organic components decrease obviously (dash curve) and thoroughly disappear until the film is annealed at 600℃for 1h in air (dot curve), which indicates that the precursor films are completely decomposed by the heat treatment process. The infrared reflection spectra of the undoped ZnO thin film scarcely show any major difference as compared with those of the In-doped thin film (not shown). Figure 2 indicates x-ray diffraction at grazing incidence (α=1°) patterns of In-doped ZnO thin films with different concentrations (In/Zn=0, 1, 2, 3 and 5 at.%) on quartz substrates. All the thin films were preheated at 350℃followed by annealed at 600℃for 1h in air. The use of GI-XRD technique, which is more appropriate in the studies of surface structure properties of the films, reveals the presence of several crystalline orientations in the prepared films. These peaks at about 31.8o, 34.5o, 36.3o, 47.6o and 62.9ocorrespond to the diffraction planes (100), (002), (101), (102) and (103) in ZnO with the hexagonal wurtzite, respectively. The (002) and (103) diffraction peaks become predominant compared to the others, which deserves to be discussed. No phases corresponding to indium oxide or to other indium compounds were detected.For convenience here a parameter P is defined, which is the intensity ratio of the (103) to (002) peaks (P=I(103) /I(002)). The value P is plotted as a function of dopant concentration for In-doped ZnO thin films as shown in figure 3, and the intensity values of the (002) and (103) peaks are also exhibited. The intensity of the (002) peak gradually decreases and then scarcely changes with increasing In concentrations, whereas that of the (103) peak always rises except a small reducing at the 1 at.% concentration. It is found that, from the asterisk curve, the value P hardly changes up to ～2 at.%, whereafter increases suddenly upon further increasing In concentrations, which indicates ～2 at.% is a critical doping concentration for In-doped ZnO thin films. The variation could be related to the solid solubility limit of the dopant element in the ZnO lattice, which is 1-2 at.% for the In-doped thin films [15]. The values of P varying from 0.52 (undoped) to 2.83 (5 at.%) are all bigger than that of ZnO powder (0.29), which was calculated according to JCPDS records. It is well known that the (002) diffraction peak is the strongest in ZnO thin films due to its lowest surface energy [16], but when more In impurities (above ～2 at.%) are introduced in the thin films, the (103) plane become gradually the most important growth orientation instead of the (002) plane with increasing dopant concentrations. This behavior reveals that the surface energy of the (103) plane might be reduced due to the In doping.In order to compare the measurement difference between GI-XRD and C-XRD, all the same samples were performedconventional x-ray diffraction on the same apparatus. As shown in the figure 4, the particularly concerned (103) peak doesn’t appear in the patterns. The (002) diffraction peak is the only evident one at around 34.42oindicating that these samples all exhibit preferential orientation with the c-axis orientation of ZnO grains perpendicular to the substrate. The peak intensity of the film with 1 at.% concentration is much stronger compared to the others (figure 5),/doc/2bbee4c72cc58bd63186bddf.html which is consistent with the results of others [15,17]. The peak intensity decreases gradually at higher doping concentration, which is supposed that redundant In atoms in ZnO thin films prevent the grain growth in (002) direction [18]. To validate the dependability of experiments, In-doped ZnO thin films prepared on silicon substrate by magnetron reaction sputtering were carried out GI-XRD and C-XRD, and the measurement results were in agreement with those described above.The penetration depth of x-rays inside the films increases with the increase of the incidence angle of GI-XRD, and structure information of a deeper layer of the films is revealed. Therefore, the In-doped ZnO thin film with 1 at.% was detected using GI-XRD at different incidence angles (α=1, 2, 3 and 5°) as shown in Figure 6, and the intensity of (002) and (103) peaks and the calculated values of P were plotted as functions of incidence angle in the figure 7. As can be seen, the results are in accord with our expectation. The reduction of the (103) peak intensity atα=5° reveals that ZnO grains with (103) plane decrease under the surface of the film, which is a apparent evidence of structure transition from the surface to the bulk. Tarey et. al [19] reported that titanium nitride films on stainless steel (SS) substrates, deposited by cathodic arc plasma deposition method in presence of nitrogen atmosphere, were detected using GI-XRD and C-XRD, and the results suggested that different crystal phases were present at the surface and in the bulk of the films. Nath, et. al [20] also found that there were different diffraction patterns using GI-XRD and C-XRD for La0.8Ca0.2MnO3 epitaxial thin films.GI-XRD is a scattering geometry combining the Bragg condition with the conditions for x-ray total reflection from crystal surfaces. This provides superior characteristics of GI-XRD compared to C-XRD in the studies of thin surface layer of films [21], since the penetration depth of x-rays inside the films is reduced by three orders of magnitude typically from micron to nanometer. The thicknessof the ZnO thin films was analyzed in the range of 210-240 nm as shown in table 1. According to the different penetration depths of x-rays between two scattering geometries, it is suggested that ZnO grains with the (103) plane only present on the surface layer of the thin films. As the dopant incorporated into ZnO thin films is below the critical concentration ～2 at.%, In atoms are preferably located at substitution sites (Zn sites), and the In concentration of 1 at.% is the optimum doping for ZnO thin films. Whereas above ～2 at.%, the dopant atoms start to segregate at the grain boundaries, which restrain the growth of the (002) orientation and simultaneously further enhance that of the (103) orientation due to the decrease of the surface energy of the (103) plane. The growth of the (002) orientation in the bulk of ZnO thin films is also deteriorated, which may result from the stresses formed by the different ion sizes between zinc (0.74?) and the dopant Indium (0.81?) [22] and from the segregation of dopant in grain boundaries for high doping concentrations. The grain sizes corresponding to (002) and (103) diffraction peaks in the Fig. 2 and Fig. 4 were summarized in Table 1. It is very clear that the grain size associated with the (002) peak measured by C-XRD is much larger than that of GI-XRD related to either the (002) or (103) peak. Therefore, it is proposed that the ZnO thin films have different crystal structures at the surface and in the bulk. That is, large grains with (002) plane are packed up to form the bulk layer of the films along perpendicular orientation with the substrate, and small grains with (002) and (103) planes comprise the surface layer.4. ConclusionsIn-doped ZnO thin films were prepared on quartz substrate by sol-gel spin-coating technique. The results of FTIR indicate that the ZnO precursor films are thoroughly decomposed bypost-deposition heat treatment. All the thin films mainly show (002) and (103) diffraction peaks in the GI-XRD patterns. The (103) diffraction peak gradually becomes the preferential growth orientation instead of the (002) peak. The (002) peak intensity increases while the (103) peak intensity decreases detected by GI-XRD at large incidence angle. However, the preferred (002) peak solely appears in the C-XRD patterns and the (103) peak doesn’t exhibit. The critical concentration ～2 at.% is related to the solid solubility and 1 at.% is the optimum doping concentration for In-doped ZnO thin films. According to the different mechanisms between GI-XRD and C-XRD, it is proposed that the ZnO thin films is composed of the bulk layer packed up by large grains with (002) plane and the surface layer by small grains with (002) and (103) planes. AcknowledgementsThis work was supported by the National Natural Science Foundation of China through Grant No. 50272027. References[1]R. D. Vispute, V. Talyansky, Z. Trajanovic, S. Choopun, M. Downes, R. P. Sharma, T. Venkatesan, Appl. Phys. Lett. 70 (1997) 2735.[2]B. E. Sernelius, K. F. Berggren, Z. C. Jin, I. Hamberg, C. G. Granqvist, Phys. Rev. B 37 (1988) 10244.[3]S. Major, A. Banerjee, K. L.Chopra, Thin Solid Films 108 (1984) 31.[4]Kwang Joo Kim, Young Ran Park, Appl. Phys. Lett. 78 (2001) 475.[5]M. S. Tokumoto, A. Smith, C. V. Santilli, S. H. Pulcinelli, A. F. Craievich, E. Elkaim, A. Traverse , V. Briois, Thin Solid Films 416 (2002) 284.[6]M. de la L. Olvera, A. Maldonado, R. Asomoza, M. Konagai, M. Asomoza, Thin Solid Films 229 (1993) 196.[7]K. Ogata, K. Koike, T. Tanite, T. Komuro, F. Yan, S. Sasa, M. Inoue, M. Yano, J. Cryst. Growth 251 (2003) 623.[8]L. Yan, C. K. Ong, X. S. Rao, J. Appl. Phys. 96 (2004) 508.[9]Min-Chang Jeong, Byeong-Yun Oh, Woong Lee, Jae-Min Myoung, J. Cryst. Growth 268 (2004)149.[10]Ze-Bo Fang, Heng-Xiang Gong, Xue-Qin Liu, Da-Yin Xu, Chun-Ming Huang, Yin-Yue Wang, Acta Phys. Sin. 52 (2003) 1748 (in Chinese).[11]J. M. Bian, X. M. Li, X. D. Gao, W. D. Yu, L. D. Chen, Appl. Phys. Lett. 84 (2004) 541.[12]D. Basak, G. Amin, B. Mallik, G. K. Paul, S. K. Sen, J. Cryst. Growth 256 (2003) 73.[13]Edited by the teaching and research group of analytical chemistry in hangzhou university, Analytical chemistry handbook, V ol. 3, Chemical Industry Press, Beijing, China, 1983, pp. 611.[14]Z. Wang, H. L. Li, Appl. Phys. A 74 (2002) 201.[15]P. Nunesa, E. Fortunatoa, P. Tonelloa, F. Braz Fernandesa, P. Vilarinhob, R. Martinsa, Vacuum 64 (2002) 281.[16]N. Fujimura, T. Nishihara, S. Goto, J. Xu, T. Ito, J. Cryst. Growth 130 (1993) 269.[17]J. H. Lee, B. O. Park, Thin Solid Films 426 (2003) 94.[18]D. J. Goyal, C. Agashe, M. G. Takwale, B. R. Marathe, V. G. Bhide, J. Mater. Sci., 27 (1992) 4705.[19]R. D. Tarey, R. S. Rastogi, K. L. Chopra, The Rigaku Journal, Vol. 4 No. 1/2 1987.[20]T. K. Nath, R. A. Rao, D. Lavric, C. B. Eom, L. Wu, F. Tsui, Appl. Phys. Lett. 74 (1999) 1615.[21]U. Pietsch, T. H. Metzger, S. Rugel, B. Jenichen, I. K. Robinson, J. Appl. Phys. 74 (1993) 2381.[22]Y. T. Qian, Introduction to crystal chemistry，Press of University of Science and Technology of China, Hefei, China, 1999, pp. 197.Figure captionsTable 1 The grain sizes corresponding to the (002) and (103) peaks measured by GI-XRD and C-XRD and thickness for all the thin filmsFig. 1: FTIR reflection spectra of In-doped ZnO thin film with 3 at.% as-deposited, preheated and annealedFig. 2: GI-XRD patterns of In-doped ZnO thin films with different doping concentrations (0-5 at.%)Fig. 3: The plots of the value P, the intensity values of (002) and (103) peaks as functions of In doping concentrationFig. 4: C-XRD patterns of In-doped ZnO thin film with different doping concentrations (0-5 at.%)Fig. 5: The intensity dependence of (002) diffraction peak on In doping concentration in the C-XRD patternsFig. 6: GI-XRD patterns of In-doped ZnO thin film with 1 at.% concentration at different incidence angles (1-5o)Fig. 7: The plots of the value P, the intensity values of (002) and (103) peaks as functions of incidence angle for In-doped ZnO thin film with 1 at.% concentration/doc/2bbee4c72cc58bd63186bddf.htmlLan et. al -Fig. 1. EPS/doc/2bbee4c72cc58bd63186bddf.htmlLan et. al -Fig. 2. EPS/doc/2bbee4c72cc58bd63186bddf.htmlLan et. al -Fig. 3. EPS/doc/2bbee4c72cc58bd63186bddf.htmlLan et. al -Fig. 4. EPS/doc/2bbee4c72cc58bd63186bddf.htmlLan et. al -Fig. 5. EPS/doc/2bbee4c72cc58bd63186bddf.htmlLan et. al -Fig. 6. EPS/doc/2bbee4c72cc58bd63186bddf.htmlLan et. al -Fig. 7. EPSTables:The grain size (nm)C-XRD(002) GI-XRD(002) GI-XRD(103) Thickness (nm)(Si substrate)Refractiveindexundoped 40.4 22.8 22.5 214 1.176 1at.% 38.0 21.3 19.0 232 1.138 2at.% 38.1 17.7 18.6 244 1.105 3at.% 33.7 17.3 20.2 241 1.095 5at.% 37.1 18.5 23.9 214 1.170Lan et. al -Table 1.doc/doc/2bbee4c72cc58bd63186bddf.html。

脉冲激光沉积

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PLD中的重要实验参数
基体的加热温度
影响沉积速率和薄膜的质量
氧气的压力
过高不利于薄膜择优取向的形成过低导致化学配比失衡，内部缺陷增多
沉积时间
影响薄膜的厚度
基体与靶的距离
影响薄膜的均匀性
激光能量，频率
影响沉积速率
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PLD法制备薄膜实验流程图
安装靶材与衬底
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解决方案
•使用高致密度的靶材，同时选用靶材吸收高的激光波长。因
为液滴产生的情况在激光渗入靶材越深时越严重。靶材对激光的吸收系数越大，则作为液滴喷射源的熔融层越薄，产生的液滴密度越低。
•通过基于速率不同的机械屏蔽技术来减少颗粒物（由于PLD 产生的颗粒物的速率要比原子、分子的速率低一个数量级）。
• 脉冲激光沉积（pulsed laser deposition，简称 PLD）法制备薄膜，将脉冲激光器产生的高功率脉冲激光聚焦于靶材表面，使其表面产生高温及烧蚀，并进一步产生高温高压等离子（ T>104K），等离子体定向局域膨胀在衬底上沉积成膜。
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3
5.1 脉冲激光沉积概述
• (3) 生长过程中可原位引入多种气体，可以在反应气氛中制膜，这为控制薄膜组分提供了另一条途径
• (4) 多靶材组件变换灵便，容易制备多层膜及异质结 • (5) 工艺简单，灵活性大，可制备的薄膜种类多 • (6) 可用激光对薄膜进行多种处理等
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8
待解决的问题
• (1) 不易于制备大面积的膜。 • (2) 在薄膜表面存在微米-亚微米尺度的颗粒物污染，所制

氮含量对纯钛表面类金刚石薄膜内应力与附着力的影响

氮含量对纯钛表面类金刚石薄膜内应力与附着力的影响张艺君;张翼;尹路【摘要】目的:采用脉冲电弧离子镀膜法于不同氮含量条件下在纯钛表面制备类金刚石膜(DLC)以观察对薄膜内应力和附着力的影响.方法:在四种氮含量条件下纯钛表面制备类金刚石薄膜,利用扫描电镜观察分析不同氮含量下薄膜的表面形貌及能谱分析薄膜成分,显微压痕仪对比分析不同氮含量对薄膜厚度和硬度的影响.结果:薄膜中氮含量与氮气甲烷流量比成正比,当氮含量达到9.6％时,薄膜性能最稳定.氮掺入DLC薄膜后,改变了薄膜的微观结构,产生几十纳米量级的颗粒.SEM、XPS分析表明纳米颗粒是富氮的非晶氮化碳CNx结构.DLC/CNx致密的纳米复合结构,减小薄膜的内应力,提高薄膜对衬底的附着力.结论:氮含量的增加会形成DLC/CNx致密的纳米复合结构,减小薄膜的内应力,提高薄膜对衬底的附着力.【期刊名称】《口腔颌面修复学杂志》【年(卷),期】2014(015)002【总页数】5页(P96-100)【关键词】纯钛;类金刚石;表面改性;压痕实验【作者】张艺君;张翼;尹路【作者单位】厦门市仙岳医院口腔科福建 361012;解放军第一七四医院口腔科福建 361003;厦门市口腔医院修复科福建 361003【正文语种】中文【中图分类】R783.1纯钛作为理想的义齿支架材料已广泛应用于口腔修复领域。

但由于铸造工艺局限，会出现耐磨性差，金属离子析出，卡环折断等缺陷，这些都需要对纯钛进行表面改性来解决。

类金刚石薄膜(DLC)作为上世纪60年代发展起来的新兴工业材料已得到广泛应用，而在口腔修复中应用较少，主要是其自身存在诸多问题，如内应力较高，附着力偏低，易剥脱等[1，2]。

人们在研究类金刚石(DLC)薄膜掺氮的过程中发现，随着氮含量的增加，薄膜中的内应力下降，从而提高了DLC薄膜与基底材料之间的附着力。

Mikami等[3]认为这是DLC薄膜中氢原子含量降低所致。

Franceschini[4]指出，在DLC薄膜中掺入氮降低薄膜的内应力是sp3氮键替代了DLC薄膜中的sp2键碳所致。

一种无机沉淀-胶溶法制备二氧化钒薄膜及热致相变性能

一种无机沉淀-胶溶法制备二氧化钒薄膜及热致相变性能李尧【摘要】通过一种便捷的沉淀-胶溶方法,以硫酸氧钒、NH3· H2O和H2O23种无机化合物为原料制备VO2薄膜.XRD结果表明,经过N2下550℃热处理后,VO2薄膜晶体为P21/c单斜相.SEM和台阶仪测试表明,薄膜表面由近球形颗粒致密分布组成,颗粒粒径约为23.5nm且膜厚为142nm,EDS能谱表明该薄膜仅含有V、O 两种元素.变温电阻测试结果表明,VO2薄膜具有良好的热致相变性能,相变温度为65℃.%In this paper,a facile precipitation-peptization method was proposed to prepare VO2 film by using inorganic VOSO4-NH3· H2O-H2O2 reactants system in air under room temperature.The crystal structure of VO2 film was transferred to mon℃linic crystal structure with the spaceg roup of P21/c by annealing at 550℃.Both SEM and step measuring instrument analysis indicated that the surface of the film consisted of spherical particles with crystallite size of 23.5 nm.The thickness of film was 142 nm.EDS spectra showed that the film contained only V and O elements.The results of temperature-change resistance test showed that VO2 thin film had a good thermo-induced phase transition property and the phase transition temperature was 65℃.【期刊名称】《化学工程师》【年(卷),期】2017(031)003【总页数】4页(P10-12,16)【关键词】二氧化钒;薄膜;溶胶-凝胶;相变【作者】李尧【作者单位】北京科技大学材料科学与工程学院,北京100083【正文语种】中文【中图分类】O484.4VO2在室温接近68℃时可以发生由半导体相向金属相转变现象，同时伴随着晶体结构由单斜相（P21/c，M相）向四方金红石相（P42/mnm，R相）转化。

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