Lead halide perovskites for radiation detectors: Perspectives

Abstract

Halide perovskite, Bridgman grown single crystals have shown excellent performance for high energy radiation detectors. CsPbBr3 perovskite detectors with 1.4% energy resolution have been demonstrated. These detectors demonstrate a wide range of operations from −2 to 70 °C. Semiconductor hard radiation detectors have been used for applications in defense, medicine, and bioelectronics. In most of these applications, there is a need for the detectors to operate at room temperature and above. Previous hard radiation detector devices have used the material cadmium zinc telluride for room temperature operation [Luke et al., IEEE Trans. Nucl. Sci. 48, 282 (2001)]. There are now other semiconductors that show considerable promise. These include the halide perovskite compound semiconductors with a formula CsPbX3, where X = Cl, Br, I [Liu et al., Proc. SPIE 8852, 88520A (2013); Peters et al., J. Lumin. 243, 118661 (2022)]. These materials are also being developed for other device applications, including light-emitting diodes, lasers, solar cells, and photodetectors. It is claimed that these semiconductors are defect-tolerant, although the reason for this behavior is not well understood. Thermally stimulated current spectroscopy was used to detect electron traps in these materials to improve their performance. The halide compound cesium lead bromide has a bandgap of 2.25 eV, which makes it suitable for room temperature operation and above. They also have high permittivity. These halide perovskite semiconductors have shown room temperature detector device performance. Recently, we demonstrated hard radiation detectors using CsPbBr3 as the device platform. The detectors had 1.4% energy resolution for high-energy γ rays [He et al., Nat. Photonics 15, 36 (2021)]. The detectors demonstrate a wide temperature region from −2 to 70 °C for stable operations.