Improved Energy Resolution by Weighting Potential Optimization in CsPbBr3 Pixelated Gamma-Ray Detector

Pixelated semiconductor detectors with superior energy and spatial resolution have broad applications in the field of ionizing radiation detection. Recently, radiation detectors based on CsPbBr3 are gradually gaining acceptance due to their favorable properties. However, the energy resolution (ER) of the CsPbBr3 pixelated detector is constrained because of the unmatched electrode structure and immature electrode preparation. In this work, we report that the pixel configuration coupled with the CsPbBr3 detector thickness to achieve dynamic regulation of the 137Cs 662-keV
$\gamma $
-rays both theoretically and experimentally, which is beneficial to eliminate potential discrepancies in performance associated with the variations in crystal quality. The simulation results yield an ER that is weakly correlated with the fundamental properties of CsPbBr3 but strongly depends on the device structure. The theoretical resolution of the CsPbBr3 pixelated detector is < 1% by adjusting the pixel-width-to-thickness ratio in the range of 0.15–0.4. Furthermore, with an optimized pixel width-to-thickness ratio, the CsPbBr3 pixelated detectors achieve a resolution of 7.31% (without any signal processing) at 662 keV and show excellent stability under a large bias up to 700 V (
$2892\,\,\text {V}\cdot \text {cm}^{-{1}}$
). This study is an extension of pixelated geometry fabrication and provides a strategy for the CsPbBr3 detector to achieve better resolution.