The development of InGaAs/InP single-photon avalanche photodiodes(SPADs)necessitates the utiliza-tion of a two-element diffusion technique to achieve accurate manipulation of the multiplication width and the dis-tribu...The development of InGaAs/InP single-photon avalanche photodiodes(SPADs)necessitates the utiliza-tion of a two-element diffusion technique to achieve accurate manipulation of the multiplication width and the dis-tribution of its electric field.Regarding the issue of accurately predicting the depth of diffusion in InGaAs/InP SPAD,simulation analysis and device development were carried out,focusing on the dual diffusion behavior of zinc atoms.A formula of X_(j)=k√t-t_(0)+c to quantitatively predict the diffusion depth is obtained by fitting the simulated twice-diffusion depths based on a two-dimensional(2D)model.The 2D impurity morphologies and the one-dimensional impurity profiles for the dual-diffused region are characterized by using scanning electron micros-copy and secondary ion mass spectrometry as a function of the diffusion depth,respectively.InGaAs/InP SPAD devices with different dual-diffusion conditions are also fabricated,which show breakdown behaviors well consis-tent with the simulated results under the same junction geometries.The dark count rate(DCR)of the device de-creased as the multiplication width increased,as indicated by the results.DCRs of 2×10^(6),1×10^(5),4×10^(4),and 2×10^(4) were achieved at temperatures of 300 K,273 K,263 K,and 253 K,respectively,with a bias voltage of 3 V,when the multiplication width was 1.5µm.These results demonstrate an effective prediction route for accu-rately controlling the dual-diffused zinc junction geometry in InP-based planar device processing.展开更多
A novel ultra-low-power readout integrated circuit(ROIC) for 1 024×1 024 ultraviolet(UV) AlGaN focal plane arrays(FPA) with 18 μm-pitch was presented. In order to optimize power consumption for UVFPA readout cir...A novel ultra-low-power readout integrated circuit(ROIC) for 1 024×1 024 ultraviolet(UV) AlGaN focal plane arrays(FPA) with 18 μm-pitch was presented. In order to optimize power consumption for UVFPA readout circuit these methods were adopted, which including single-terminal amplifier under subthreshold region as CTIA amplifier, common current source load for source follow(SF) buffer in column pixels and level shift circuits, and time-sharing tail current source for column buffer. The smallest operational current of CTIA in pixel unit is only 8.5 nA with 3.3 V power supply by using single-terminal amplifier. The ROIC has been fabricated in SMIC 0.18 μm 1P6M mixed signal process and also achieved better performances with the novel design of bias current adjustable. Furthermore, the overall power consumption of the chip is 67.3 mW at 2 MHz in 8-outputs mode by the above methods according to the experimental results.展开更多
A novel tuning fork micromachined gyroscope, based on slide-film damping, is presented. The electrostatic driving gyroscope consists of two driving masses each of which supports one sensitive mass. The angular rate is...A novel tuning fork micromachined gyroscope, based on slide-film damping, is presented. The electrostatic driving gyroscope consists of two driving masses each of which supports one sensitive mass. The angular rate is sensed by the differential capacitances consisted of movable bar electrodes and fixed bar electrodes located on the glass wafer. The gyroscope can operate at atmospheric pressure with slide film damping in the driving and sensing directions, eliminate vacuum packaging and restrain cross-axis acceleration signal. The results of design and simulation show that the driving and sensing mode frequencies are 3 106 Hz and 3 175 Hz,respectively, and the Q-values in driving and sensitive modes are 1 721 and 1 450 respectively. The design resolution is 0.025°/s.展开更多
基金Supported by Shanghai Natural Science Foundation(22ZR1472600).
文摘The development of InGaAs/InP single-photon avalanche photodiodes(SPADs)necessitates the utiliza-tion of a two-element diffusion technique to achieve accurate manipulation of the multiplication width and the dis-tribution of its electric field.Regarding the issue of accurately predicting the depth of diffusion in InGaAs/InP SPAD,simulation analysis and device development were carried out,focusing on the dual diffusion behavior of zinc atoms.A formula of X_(j)=k√t-t_(0)+c to quantitatively predict the diffusion depth is obtained by fitting the simulated twice-diffusion depths based on a two-dimensional(2D)model.The 2D impurity morphologies and the one-dimensional impurity profiles for the dual-diffused region are characterized by using scanning electron micros-copy and secondary ion mass spectrometry as a function of the diffusion depth,respectively.InGaAs/InP SPAD devices with different dual-diffusion conditions are also fabricated,which show breakdown behaviors well consis-tent with the simulated results under the same junction geometries.The dark count rate(DCR)of the device de-creased as the multiplication width increased,as indicated by the results.DCRs of 2×10^(6),1×10^(5),4×10^(4),and 2×10^(4) were achieved at temperatures of 300 K,273 K,263 K,and 253 K,respectively,with a bias voltage of 3 V,when the multiplication width was 1.5µm.These results demonstrate an effective prediction route for accu-rately controlling the dual-diffused zinc junction geometry in InP-based planar device processing.
文摘A novel ultra-low-power readout integrated circuit(ROIC) for 1 024×1 024 ultraviolet(UV) AlGaN focal plane arrays(FPA) with 18 μm-pitch was presented. In order to optimize power consumption for UVFPA readout circuit these methods were adopted, which including single-terminal amplifier under subthreshold region as CTIA amplifier, common current source load for source follow(SF) buffer in column pixels and level shift circuits, and time-sharing tail current source for column buffer. The smallest operational current of CTIA in pixel unit is only 8.5 nA with 3.3 V power supply by using single-terminal amplifier. The ROIC has been fabricated in SMIC 0.18 μm 1P6M mixed signal process and also achieved better performances with the novel design of bias current adjustable. Furthermore, the overall power consumption of the chip is 67.3 mW at 2 MHz in 8-outputs mode by the above methods according to the experimental results.
文摘A novel tuning fork micromachined gyroscope, based on slide-film damping, is presented. The electrostatic driving gyroscope consists of two driving masses each of which supports one sensitive mass. The angular rate is sensed by the differential capacitances consisted of movable bar electrodes and fixed bar electrodes located on the glass wafer. The gyroscope can operate at atmospheric pressure with slide film damping in the driving and sensing directions, eliminate vacuum packaging and restrain cross-axis acceleration signal. The results of design and simulation show that the driving and sensing mode frequencies are 3 106 Hz and 3 175 Hz,respectively, and the Q-values in driving and sensitive modes are 1 721 and 1 450 respectively. The design resolution is 0.025°/s.
