Cu ion implantation induced efficient interface carrier extraction for ultra-sensitive DMAPbI3 single crystal perovskite X-ray detector

Lead halide perovskite single crystals are one of the most promising materials for radiation detection due to their unique advantages of excellent attenuation efficiency, large carrier mobility, long carrier diffusion length, and low defect density. However, the relatively low irradiation stability and severe ion migration in perovskites deteriorate the X-ray detection performance under longtime and high-field operating conditions. Herein, we synthesize a centimeter-sized organometal halide perovskite of DMAPbI3 single crystals. The effective modification strategy of Cu ion implantation is employed to suppress the ion migration and significantly improve the irradiation stability and the performance of DMAPbI3 in X-ray detection. The modification effect is evidenced by the effectively eliminated metallic lead (Pb0) defects, extends the carrier decay lifetime, increases the photoluminescence (PL) intensity and improves μτ product. As a result, the coplanar X-ray detectors with Cu ion treatment exhibits a shorten transient response time of 522 μs, an excellent sensitivity up to 11,066 μC Gyair−1 cm−2 under 50 V as well as a low detection limit of 0.16 μGyairs−1. Moreover, the combination of high stability and excellent X-ray response enables superior X-ray imaging. Finally, the DFT calculation is employed to unravel the mechanisms of implanted Cu ions induced reduction of non-radiative charge recombination and improvement of the interface charge carrier extraction efficiency. This work provides effective interface passivation strategy and insights for improving the performance of perovskite X-ray detectors.