(Mg)ZnO Photoconductive Detector Development for Direct-Conversion Hard X-Ray Detection

Wide-bandgap semiconductor-based X-ray detectors provide a number of advantages. As presented in this letter, (Mg)ZnO photoconductive direct-conversion X-ray detectors with various Mg contents were fabricated and demonstrated. The signal-to-noise ratio (SNR) and response time of the devices under 6 MV hard X-ray irradiation were significantly improved after doping with Mg. The Ag-Mg _0.19 Zn _0.81 O-Ag photoconductive detector with optimal Mg contents exhibited a sensitivity of 3.03 $\mu \text{C}$ /(mGy $_{\mathrm {air}}\cdot $ cm ³ ), a short response time of approximately 0.2 s (rise time) and 0.3 s (decay time), and a large SNR of 278 with a bias of 30 V under hard X-ray irradiation (100 mGy _air /s). The results indicate great application prospects for wide-bandgap MgZnO in direct-conversion X-ray detectors.