TRANSIENT-RESPONSE OF PHOTODETECTORS

Calculations by drift diffusion and Monte Carlo methods and experiment al data on the transient response of metal-semiconductor-metal photode tectors are reported. We have shown how the interplay of carrier and d isplacement currents, inhomogeneities in field and charge distribution s, and hot electron effects determines observed structure in the trans ient response. In particular, we have demonstrated the role played by the regions under the contacts that are not illuminated in forming pea ks in the transient response. We have also demonstrated that the peaks in the transient response need not be attributed to velocity overshoo t and the scaling of detector response with contact separation has bee n studied. (C) 1996 American Institute of Physics.