Radiation damages of InGaAs photodiodes by high-temperature electron irradiation

Results are presented of a detailed study of the effects of high-temperature 2-MeV electron irradiation on the performance degradation of InGaAs photodiodes. The macroscopic device performance will be correlated with the radiation-induced defects, observed by DLTS. It was found that the dark current increases after irradiation, while the photo current decreases. After irradiation, one majority electron capture level with (Ec-0.37 eV) was induced in the n-InGaAs layer, while no minority hole traps were found. Additionally, the degradation of the device performance and the introduction rate of the lattice defects decrease with increasing irradiation temperature. For a 300 deg. C irradiation, the reduction of the photo current is only 40% of the starting value. This result suggests that the creation and recovery of the radiation damage proceeds simultaneously at high temperatures