Numerical Study of Dual band (MW/LW) IR Detector for Performance Improvement

Abstract

In the present study, an extensive numerical analysis has been performed and an effort has been made to understand the underlying physics, which is presently unclear for researchers for development of third generation FPA infrared detectors based on HgCdTe material. To reduce technology development cost associated with dualband photodetector for operation at MWIR and LWIR regions, a 2D theoretical model has been proposed including all the relevant physics. The structure under present study considers back-to-back diode structures to detect simultaneous MW/LW operative wavelength by changing the biasing polarity of the diodes. The optimum electrical and optical outputs from dualband detector have been achieved through performing design of experiments. The coupled basic semiconductor equations including nonlinear continuity, transport and Poisson’s equations have been solved to achieve electrical (I-V) characteristics under no bias condition and modern optics equations has been coupled to semiconductor equations to obtain optical characteristics. The quantum efficiency of both detectors has been computed and compared with experimental results. The computed results obtained on the basis of proposed model accurately matches with the experimental results reported by others researcher. The results exhibit the quantum efficiencies, QEMW=95 per cent and QELW=74.5 per cent, respectively.