CdZnTe Detectors Operating at X-ray Fluxes of 100 Million $\mathrm {Photons}/(\mathrm {mm}^{2.}\mathrm {sec})$

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 $120~\mathrm {kV}_{\mathrm {p}}$ fluxes up to $10^{8}~\mathrm {photons}/(\mathrm {mm}^{2.}\mathrm {sec})$ 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.