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CdZnTe (CZT) is a promising commercial material used as a room-temperature operating semiconductor detector for gamma-ray detection. Recently, CdZnTeSe (CZTS) detectors improved upon the properties of CZT by improving homogeneity and reducing defect properties, thereby enabling higher production yield of high-quality crystals. However, addition of selenium to CZT will reduce the bandgap and increase the amount of thermally stimulated electrons, resulting in low resistivity of the crystal. In this study, the enhancement of zinc content was introduced to compensate the bandgap reduction owing to selenium addition, while maintaining the improved properties of selenium addition. The morphology and stoichiometry of CZTS were determined using scanning electron microscopy and electron probe micro-analyzer. Furthermore, the calculated bandgap with stoichiometry was compared with the measured bandgap using UV–Vis measurement and Tauc plot. The electrical, chemical, and other spectroscopic properties were characterized using an I–V curve, X-ray photoelectron spectroscopy, and gamma-spectroscopic techniques, respectively. Moreover, it was proven that the high zinc CZTS can exhibit superior properties owing to selenium addition without affecting the bandgap reduction. • The high Zn content CdZnTeSe(CZTS) was grown with Bridgman technique, allowing the higher energy bandgap and resistivity compared to common CdZnTe(CZT). • The modified characteristics of high Zn CZTS are identified by the analyses for morphological, optical, electrical, transport, and spectroscopic properties. • The CZTS, rich in zinc, has shown superior performance in transport and spectroscopy, making it a potential candidate for the next-generation commercial detector. [ABSTRACT FROM AUTHOR]

Organic-inorganic perovskite single crystals (SCs) are considered promising semiconductors for high-sensitivity X-ray detectors because of their strong X-ray interaction, low-temperature processability, and excellent properties such as long diffusion length, low defect density, and long carrier lifetime. However, the specific pulse response of MAPbBr 3 SC-based X-ray detectors frequently exhibits a tail and over/undershoots at several conditions, which degrades the X-ray image quality; however, no detailed analysis of these characteristics has been reported thus far. For high-resolution X-ray imaging, it is necessary to obtain an ideal pulse response that is free of tails and over/undershoots. In this study, we investigated the specific X-ray responses of solution-grown MAPbBr 3 SC-based X-ray detectors under various externally applied voltages. Based on the study on charge carrier dynamics, we analyzed the origin of the tail and over/undershoots in X-ray pulse response shapes. We theoretically verified that the unideal pulse response in perovskite SC-based X-ray detectors is attributed to the defect states inherent in perovskite SCs. • X-ray responses of MAPbBr 3 single-crystal detectors with different electrodes are investigated. • The specific pulse responses of the detectors show tail and over/undershoots. • Tail and overshoots can be interpreted as de-trapping and trapping, respectively, on shallow traps. • Undershoot is caused by diffusion currents due to the internal fields and unoccupied vacancies. [ABSTRACT FROM AUTHOR]