Software for modeling x-ray signals, as detected by a semiconductor radiation detector, has been developed. We model a generic signal generation/collection/processing sequence using Monte Carlo and finite-element analysis software. The suggested framework will allow one to simulate x-ray pulse-height spectrum, various triggering schemes, and can be used for detector optimization.
In recent years, operation of wide band-gap semiconductor detectors under high-flux irradiation in medical and
security applications has called the attention of the scientific commnity. However, under high-flux irradiation,
these detectors are limited by poor hole transport properties and other factors. In our studies, the build up
of space charge as a function of time has been systematically investigated through direct comparison between
experiments and charge transport simulations. In order to benchmark and calibrate our simulations, charge
transport properties of CdZnTe detectors used in high-flux experiments were measured. Our results show that
the polarization effect, caused by the build up of positive space charge as a function of time, initially distorts
and eventually causes complete breakdown of the operating electric field.