Gamma-ray irradiation effects on CdTe solar cell dosimeter

Compact and radiation-tolerant radiation dosimeter without bias voltage application using solar cells such as CdTe was proposed for severe radiation environment near a nuclear reactor pressure vessel. In this work, γ-ray tolerance and γ-ray detection characteristics of CdTe solar cells were investigated. It was found that the CdTe solar cell has sufficient tolerance against γ-ray exposure up to 3 MGy. It was demonstrated that γ-ray induced current density linearly increased with increasing γ-ray intensity in the range up to approximately 1.5 kGy h−1. This result indicates that high dose-rate radiation detection can be performed using solar cells without voltage application. In addition, γ-ray sensitivity was successfully improved by a stack of CdTe solar cells with parallel connections. Furthermore, γ rays can be detected with high responsivity and small noise even under a high flux neutron environment.