Modification of CsPbBr3/p-Si Heterojunction Properties using Gamma Ray Irradiation

Halide perovskite materials have received significant attention of researchers in various applications, such as solar cells, batteries, supercapacitors, and particularly sensors. In this study, CsPbBr 3 /p-Si heterojunction thin film was successfully fabricates by facile thermal evaporation, and comprehensively investigates the impact of gamma irradiation (0 to 75 kGy) on the structural, morphological, optical, and I-V characteristics. The structural parameters measured via XRD confirm the formation of orthorhombic phase, and the crystallite size increases while micro-strain decreases with increasing irradiation. FE-SEM experiments reveal a CsPbBr 3 thin-film cross section of approximately 233 nm and confirm the variation in grain size with irradiation, and EDX analyses confirm the purity and quality of the thin film. From optical perspective, a notable decline in the energy bandgap from 2.38 eV to 2.20 eV was observed with increasing irradiation dose, which is caused by the increase in crystallite size and formation of defects. Furthermore, current–voltage (I-V) measurements suggest an increase in the saturation current, whereas the ideality factor, barrier height, and series resistance exhibit a diminishing trend with increasing gamma exposure. The gamma-induced structural defects significantly influenced CsPbBr 3 /p-Si heterojunction thin film characteristics, highlighting its potential for advanced sensing applications.