基于CMOS技术的太赫兹源和探测器设计@UCMMT2020

Design of THz Source and Detector in CMOSLeijun Xu，Zhijian XieSchool of Electrical and Information Engineering, Jiangsu UniversityOUTLINES11Background 12THz source design 13Fabrication & Measurement 14THz detector design Conclusion15Application: security, biomedical imaging, quality detection, etc.1. Background(a) THz-TDS (b) THz detection system based onsolid-state circuitsLow f maxOutput power, DC-to-THz efficiencyLimitsOn-chip antennaTHz detectorMatchingCMOS ChallengesSilicon substrate High lossSpecifications: Output power, DC-to-THz efficiency, Tuning range, etc.Source typesMultiplier OscillatorHarmonic OscillatorThe fundamental component is subtracted, while second harmonic is superimposed .Output of the V 1:Output of the V 2:Output of the oscillator:100()cos()n n V t a n t ωϕ∞=+∑200()co s()n n V t a n t n ωϕπ∞=++∑out 1202,4,...()=()()2cos()n n n V t V t V t a n t ωϕ∞=+=+∑Push-push oscillator Equivalent circuitY in1Y in2V out(t)Y LV 1(t)V 2(t)A◆Triple-push oscillator’s third harmonic is superimposed, which is similar to push -push structure.Our propsed Push-push VCO: (1) improved output power (2) bulk voltage controlSchematic of push-push VCO Output powerOn-chip antenna with rectangular slot (280~340GHz)Ground PlaneM10M1Model of the on-chip antenna with rectangular slot S11 of the on-chip antenna1×2 VCO arraySchematic of1×2 push-push VCOOn-chip antenna with T-shaped slot for 1×2 push-push VCOModel of the on-chip antenna with T-shaped slot S11 of the on-chip antenna2. THz source Design3. THz detector design Sensitivity is the most concerned for THz detector.DirectDetection modesHeterodynePrinciple of self-mixing detection for MOSFET.CMOS or HEMT0g ds ds i G V =（V ）g g g =cos =cos +ds ds ds ds ds g g V V V V V V V V V V δδωδδδωφδ⎧⎧→+⎪⎪⇒⎨⎨→+⎪⎪⎩⎩（） （）Background current Photon current 0g ds 0g g 1+cos 2ds ds i G G V δδφ=（V ）V （V ）V （） a.Materials with higher electron mobility;b.An efficient THz antenna.Antenna efficiency3. THz detector design40nm CMOSDyakonov-Shur theory ：()th gs RFV V V U --=∆42Principle of self-mixing detection for MOSFET.3. THz detector designDirect detector and serpentine on-chip antenna (300GHz)Schematic of direct detector Model of the serpentineon-chip antennaS11 of the on-chip antennaHeterodyne detector (RF/LO: 300GHz, IF : 0.1~17GHz)Schematic of heterodyne mixing structure Schematic of IF amplifierRing differential on-chip antenna for heterodyne detectorGround PlaneModel of the ring differential on-chip antenna S11 of the on-chip antennaTHz sources and detectors were fabricated in 40nm CMOS technologyHeterodyne Detector Direct DetectorPush-PushVCO1×2 Push-PushVCO ColpittsVCOPush-PushVCO (Probe)Die photo of the THz sources and detectors (Size: 1mm ×1mm)4. Fabrication & MeasurementBonding package of the chip and the PCB for testing Bonding package of the chip(Size: 2.3cm×2.3cm)PCB for testing(Size: 10cm×7cm)Radiation intensity measurement of 1×2 push-push VCORadiation intensity test of THz sourceThe intensity of radiationRadiated power measurement of THz sourceMeasurement setup for radiated power of THz sourceRadiation power measurementPlatform for THz source & detector self-testMeasurement setup for THz self-test system Test platformResults of THz detector responsivityResults of the THz detector voltage responseTHz sources and detectors designed in 40nm CMOS technology:•Push-push VCO with rectangular slot on-chip antenna (Size: 410μm×230μm)•1x2 push-push VCO with T-shaped slot on-chip antenna (Size: 360μm×300μm)•Heterodyne detector with ring differential on-chip antenna (Size: 670μm×360μm)•Direct detector with serpentine on-chip antenna (Size: 260μm×306μm)CMOS Tech.Freq.[GHz]P rad /P out [dBm]P dc [mW]Size [mm 2]Ref.65nm 101NA 11.90.0025[1]65nm 163-14330.0462[2]40nm 340.6-11.134.10.028[3]40nm 309-10640.016This workCMOS Tech.Freq.[GHz]R v [kV/W]NEP [pW/Hz 1/2]Size [mm 2]Ref.55nm 25800.041100NA [4](direct)180nm 650 5.59.10.0064[5](direct)65nm 490140 1.20.528[6](heterodyne)40nm30940 6.20.08This work(direct )Table 1Parameters comparison of THz oscillatorTable 2Parameters comparison of THz detectorReference[1]X. Yi, C. C. Boon, J. F. Lin, and W. M. Lim, “A 100 GHz transformer-based varactor-less VCO with 11.2% tuning range in 65nm CMOS technology,”in Proc. ESSCIRC, Bordeaux, 2012, pp. 293-296.[2]H. Koo, C. Kim, and S. Hong, “A G-band standing-wave push-push VCO using a transmission-line resonator,”IEEE Trans. Microw. Theory Techn., vol. 63, no. 3, pp. 1036-1045, March 2015, 10.1109/TMTT.2015. 2398445.[3]C. Li, C. Ko, C. Kuo, M. Kuo, and D. Chang, “A 340 GHz triple-push oscillator with differential output in 40 nm CMOS,” IEEE Microw. Wireless Compon. Lett., vol. 24, no. 12, pp. 863-865, Dec. 2014,10.1109/LMWC.2014.2352936.[4]D. Shang, Y. Xing, and P. Sun, “Short-channel MOSFET for terahertz wave detection fabricated in 55 nm silicon CMOS process technology,” Electron. Lett., vol. 55, no. 25, pp. 1357-1358, 2019, 10.1049/el.2019.2879.[5]Q. Yang, X. Ji, Y. Xu, and F. Yan, “Improved performance of CMOS terahertz detectors by reducing MOSFET parasitic capacitance,” IEEE Access, vol. 7, pp. 9783-9789, 2019, 10.1109/ACCESS.2018.2889154.[6]K. Choi, D. R. Utomo, and S. Lee, “A fully integrated 490-GHz CMOS heterodyne imager adopting second subharmonic resistive mixer structure,” IEEE Microw. Wireless Compon. Lett., vol. 29, no. 10, pp. 673-676, 2019, 10.1109/LMWC.2019.2936685.AcknowledgementHere show our great appreciation to professor Li Qin, from Southeast university, for giving valuable advice during the design. This work is sponsored by National Natural Science Foundation of China (Grant No. 61874050).Thank You！。