Numerical simulation of two-color infrared Hg1−xCdxTe detectors for optimizing design

The performance of two-color middle wavelength photovoltaic Hg_1-xCd_xTe detector is studied numerically for optimizing design. Simultaneous mode is designed for the two-color detector. The effect of SRH recombination electron lifetime in p-region on spectral response is examined, and the dependence of crosstalk on composition gradient of barrier layer is analyzed. Simulation results show that quantum efficiency decreases rapidly with decrease of SRH electron lifetime in p-region, at least about 10ns of SRH electron lifetime is required for better performance of the detector. Crosstalk decreases to the steady value determined by optical crosstalk as the composition gradient of barrier layer increases to about 0.03, so critical composition gradient of about 0.03 is necessary for suppressing the electrical crosstalk.