Impact of lattice defects on the performance degradation of Si photodiodes by high-temperature gamma and electron irradiation

Abstract

Results of a detailed study of the effects of high-temperature γ-ray and electron irradiation on the performance degradation of Si pin photodiodes are presented. The macroscopic device performance will be correlated with the radiation-induced defects, observed by DLTS. After irradiation, two majority electron capture levels with ( E c−0.22 eV) and ( E c−0.40 eV) were induced in the n-Si substrate, while one minority hole capture level with ( E v+0.37 eV) was found. It was found that the dark current increases after irradiation, while the photo current decreases. Additionally, the degradation of the device performance and the introduction rate of the lattice defects decrease with increasing irradiation temperature. At 200°C irradiation, the reduction of the photocurrent is only 10% of the starting value. This result suggests that the creation and recovery of the radiation damage proceeds simultaneously at high temperatures.