Simulation of MWIR and LWIR photodiodes based on n+-p and p-n junctions formed in HgCdTe heterostructures

Realization of affordable large format high performance photovoltaic (PV) infrared (IR) Hg1-xCdxTe based focal plane arrays (FPA) covering spectral ranges Mid-Wave (MWIR) from 3 to 5.5 mu m and extended Long-Wave (LWIR) from 8 to 14 mu m requires comprehensive estimation of photodiodes performance depending on Hg1-xCdxTe material properties and operating conditions. Advanced Infrared Focal Plane Arrays include Mid-Wave (MWIR) 3-5.5 mu m operating at temperatures T-op = 80-100 K and at higher temperatures (HOT) T-op=200-240 K, extended Long-Wave (LWIR) 8-14 mu m operating at temperatures T-op=80-100 K and multi-color arrays. Perhaps novel FPA will be based on photodiodes (PD) with p-n junction opposite to usually used n(+)-p junction. PD with optimal p-n junction could have lower dark current value than same size n(+)-p junction. It is desirable for proper multiplexing of PD arrays to Silicon Read-out Integrated Circuits (ROICs). Comparative analysis of LWIR PD performance at 80 K and 100 K is needed also due to strong tendency to lowering weight and power consumption of perspective megapixel FPA. Objective of the present work was to calculate Hg1-xCdxTe MWIR and LWIR PV FPA (lambda(p) equals to 4.5-4.8 mu m at T-op=225 K responding 2-3 stages thermal electric cooler temperature and 8.0-9.0 and 10.0-10.5 mu m at T-op=80-100 K) performance variation with doping level, absorber thickness, surface recombination rate and operating temperature.