Radiation-resistant InGaAs nanoscale air channel photodiodes

The nanoscale air channel photodiode (NACPD) is an emerging device that combines the advantages of vacuum phototubes and semiconductor photodiodes. Its ballistic transport mechanism theoretically enables high-speed operation and high radiation hardness. However, the irradiation performance of NACPDs has not yet been fully investigated. This study investigates the effects of gamma and neutron irradiation on the performance of InGaAs NACPDs. Experimental results show that gamma irradiation has a more pronounced impact on the dark current than neutron irradiation. After exposure to 100 krad(Si) gamma radiation at a dose rate of 10 rad(Si)/s, the dark current increased by approximately 40%. In contrast, the dark current remains largely unchanged following 1.2 MeV neutron irradiation up to a fluence of 5 × 1011 n/cm2. Both gamma and neutron irradiations have minimal influence on the photocurrent, with variations remaining below 10%, and devices exhibited stable performance before and after irradiation. These findings indicate that InGaAs NACPDs possess exceptional radiation tolerance, making them promising for photodetection and sensing applications in space missions and nuclear power environments.