Low-dimensional Photodetector And Low Temperature Readout

The low-dimensional structure of semiconductor has rich and profound effects,such as artificial cutability,quantum size and resonance tunneling effect.This makes it become the driving force of the semiconductor detector technology.The high operating speed and negative differential resistance characteristics of the resonant tunneling effect have aroused great interest of researchers.Meanwhile,because of the large dark current of the low dimensional photodetector at room temperature,we should suppress the excessive dark current of the photodetector by cooling to improve the sensitivity and signal-to-noise ratio.In this paper,the simulation analysis and readout characteristic at low temperature in the low-dimensional photodetector are studied.The crosslight Apsys simulation software has used to analysis the resonant tunneling of carriers in AlGaAs/InGaAs Photodetector and study the influence of intergrating the structure of the dot in the well on dark current,signal-to-noise ratio and detection rate of n-i-n double barriers quantum dot.By studying the energy band of the p-i-n photodetector,low temperature ?-? characteristics,photocurrent spectrum characteristics and photoluminescence characteristics,the temperature effect on the tunneling probability,the band position and the readout characteristics of the low dimensional semiconductor photodetector has analyzed.The main factors influencing the low temperature CMOS circuit have analyzed by literature investigation and simulation based on the low temperature readout design.We test the digital and analog characteristic of the 2×8 readout circuit at 42 K by Janis SHI liquid helium cycle cooling test system.