Numerical analysis of the detectivity in n(+)-n-p and p(+)-p-n GaInAsSb infrared detectors

In this paper, the detectivity for n(+)-n-p and p(+)-p-n GaInAsSb infrared detectors in both the front- and backside illuminated cases are calculated and analyzed, respectively. The influence of the carrier concentration and width in each layer, as well as the surface recombination velocities at dif ferent surfaces of the detectors are considered. It is indicated that high R(0)A dose not guarantee the high detectivity because the quantum efficienc y combines with the R(0)A to determine the behavior of D*. On the base of t he calculations, it is observed that the different material parameters are required for the optimum D* in the different structures with the different directions of the light injected. (C) 1999 Elsevier Science Ltd. All rights reserved.