Radiation Hardness of an α-Ga₂O₃ Nanorod Array/FTO Solar-Blind Photodetector Against the 50-MeV Proton Beam

Radiation hardness of one α-Ga 2 O 3 nanorod array/FTO solar-blind photodetector against 50MeV protons was tested at the Huairou Proton Cyclotron, China. The α-Ga 2 O 3 nanorod array/FTO samples were first subjected to proton irradiation with fluence up to 5×10 13 p/cm 2 , and then used as the photoanode and the photoelectrochemical properties including the light current, dark current and responsivity were measured. We demonstrate that the responsivity of the photodetector at 0V is 37% declined at 5 × 10 12 p/cm 2 proton fluence. The photodetector can be still used to detect the UV light after 50MeV proton irradiations with fluence 5×10 12 p/cm 2 , implying its potential applications in space. The damage mechanism of the α-Ga 2 O 3 nanorod array/FTO samples due to proton irradiation is then analyzed using the SRIM&TRIM code, which indicates that both the ionization and displacement damage contribute to the responsivity degradation.