Mathematical modeling of photoconductor transient response

We present a Photoconductor device model that is based on time-dependent convective/diffusive continuity and transport equations. Electron and hole trapping on deep-level impurities is accounted for by trapping-kinetics rate equations. The coupling between carrier drift and electric field is completed through Poisson's equation. The system of model equations is solved numerically with boundary conditions that represent ideal ohmic contacts. Computed results are presented for different photoconductor lengths and bias voltages with spatially uniform, rectangular light-pulse excitation. Material parameters appropriate for iron-doped indium phosphide are used.