CdZnTe Detectors Operating at X-ray Fluxes of 100 Million Photons/(mm2.sec)

CdZnTe single crystals grown with the traveling heater method have been specifically engineered to support high-flux x-ray photon counting applications. Pixelated detector devices absorb hardened 120 kVp fluxes up to 108photons/(mm2·sec) without any sign of electric field polarization at room temperature (23-28) °C. It is shown that detector functionality can be verified using photon counting electronics even under conditions of strong pulse pile-up. A non-paralyzable counting model satisfactory describes the average output count rate of the detector-electronics system as a function of the absorbed flux. Good pixel-to-pixel count rate uniformity can be achieved.