Induced lattice defects in InGaAs photodiodes by high-temperature electron irradiation

Abstract

Results of a detailed study of the effects of high-temperature 2-MeV electron irradiation on the performance degradation of InGaAs photodiodes are presented. The macroscopic device performance will be correlated with the radiation-induced defects observed by deep level transient spectroscopy. It was found that the dark current increases after irradiation, while the photocurrent decreases. After irradiation, one majority electron capture level with (Ec−0.37eV) 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°C irradiation, the reduction of the photocurrent is only 40% of the starting value. This result suggests that the creation and recovery of the radiation damage proceeds simultaneously at high temperatures.