Ultimate parameters of Hg1-xCdxTe and InAs1-xSbx n(+)-p photodiodes

Ultimate parameters of HgCdTe and InAsSb n(+)-p photodiodes for the 5-mum s pectral region operating at a temperature of 220 K have been determined. Pa rameters of these devices are limited by noise coming from statistical proc esses of thermal generation and recombination of carriers. In the case of H gCdTe photodiodes. only two processes are important, Auger 1 and Auger 7, w hereas in InAsSb photodiodes the Auger S process is dominant. It is proved that Hg1-xCdxTe and InAs1-xSbx photodiodes constructed optimally have simil ar detection parameters. In both types of photodiodes, broadening of the en ergy band gap in the n(+) region leads to a similar, almost twofold increas e in the normalized detectivity. (C) 2001 Elsevier Science Ltd. All rights reserved.