Total Ionizing Dose Effects on Solar-Blind Ultraviolet Focal Plane Arrays

Abstract

The study of the effect of γ-rays on the characteristic parameters of the AlGaN ultraviolet focal plane arrays (UVFPA) was carried out to address the problem of degradation of the characteristic parameters of the solar-blind UVFPA after irradiated by energetic particles in the space environment. The AlGaN UVFPA was irradiated with 60Co γ-rays and annealed at room temperature after irradiation. The dark current, noise voltage, responsivity, detectivity, and other characteristics of the UVFPA were compared before and after irradiation and annealing to summarize the changes of the UVFPA characteristics and to analyze the radiation effect mechanism of AlGaN UVFPA. The experimental results show that as irradiation dose increases, the dark current increases, and the responsivity decreases. After annealing of irradiated sample at room temperature, the degradation of the characteristic parameters caused by irradiation is restored. We believe that the effect of ionizing radiation leads to the increase of leakage current in MOS transistor and threshold voltage drift, resulting in the change of the UVFPA operating point and degradation of the characteristic parameters.