Fig. 1. (a) The measured photocurrent and corresponding gain at 532 nm of the devices biased at 1.1 V_br, which show negligible variations compared with the values before radiation. (b) Leakage current as a function of reverse voltage before and after radiation at room temperature. During the radiation, the samples are biased at 0.9 V_br, 1.1 V_br and unbiased, respectively, with the total radiation dose of 100 krad(Si) and dose rate of 50 rad(Si)/s. The inset shows the negligible changes of V_br after radiation.

Fig. 2. Temperature-dependent (a) forward and (b) reverse I–V curves. (c) Comparison of measured temperature-dependent ideality factor n and their fitting results before and after radiation. (d) Arrhenius plot of leakage current measured at 20 V and the fitting results as a function of temperature before and after radiation.

Fig. 3. Time evolution of leakage current after radiation. Leakage current of the unbiased device is traced at 29.7 V at room temperature for 568 hours (red square) and annealed at 200 °C for 2 hours (blue square), after which the leakage current approaches its initial value before radiation (black square).

Table 1. Leakage current changes at 29.7 V before and after γ-ray radiation test.

Table 2. Comparison of DCR before and after radiation while keeping PDE at 5 %.