SIMULATION OF CHARGE TRANSPORT IN SEMICONDUCTOR RADIATION DETECTORS

The performance of semiconductor radiation detectors is strongly influenced by the trapping and detrapping of electrons and holes in the semiconductor crystals used in their fabrication. Unfortunately, these effects are very difficult to predict analytically, even when assuming simple conditions such as constant electric field. We report on a technique which computes the induced current pulse as a function of time in semiconductor detectors using Monte Carlo methods. The charge collection efficiency may then be computed from the current pulse by integration. This technique uses a computer program which simulates the trapping and detrapping of individual charge carriers within a semiconductor detector under a broad range of conditions. For boundary conditions where analytical solutions exist, excellent agreement is obtained with the results of our simulation. © 1990.