CdTe detectors responses to pulsed X-rays : comparison of different materials

Abstract

ABSTRACTThe goal of this work is to compare and analyze the transient responses to X-ray pulses of different cadmium telluride detectors:- CdTe: Cl grown by the vertical Bridgman method (B.).- CdTe: Cl grown by the Travelling Heater Method (T.H.M.).- Cd0,8 Zn0,2 Te grown by the High Pressure Bridgman method (H.P.B.).Photoconductive detectors were subjected to very short (20 ns) 100 keV X-ray pulses and short (4 µs) 2 MeV pulses. The transient response of the photoconductors CdTe: Cl and CdZnTe under high X-ray energy beam were characterized in terms of sensitivity, linearity and dynamic range vs different parameters such as bias voltage and X-ray beam fluence. Bridgman and T.H.M. detectors show similar behaviors while H.P.B. detectors which are highly resistance show shorter transient behavior after the 20 ns pulses irradiations and larger afterglow after the 4 µs pulses irradiations.