Numerical simulation of SPIR detectors

A two-dimensional numerical simulation has been used to analyze SPIR detectors. Simulation models are based on a current continuity equation, which accounts for carrier generation, recombination and drift-diffusion processes as functions of position and time. We investigate the transit time dispersion due to a non-uniform electric field for the various read-out geometries and the variation of read-out voltage with the mismatch between drift velocity of photogenerated carriers and scan velocity of incident signal. The results have been used to derive an approach for optimization of device structures and operation conditions