Study of Neutron Radiation Effects in Optical MOS Solid-State Relays

Optical MOS solid-state relays provide electrical isolation and favorable switching performance, making them suitable as isolated switching interfaces for optoelectronic sensors used in radiation monitoring systems, high-energy physics accelerator monitoring systems, and aerospace electronic equipment. However, to the best of our knowledge, the reliability of this device under atmospheric-like neutron irradiation has not been systematically investigated. In this study, the neutron-induced degradation characteristics and potential physical mechanisms of a commercial optical MOS solid-state relay were systematically investigated through electrical characterization, Sentaurus TCAD mixed-mode simulation, and post-irradiation annealing experiments. Particular attention was paid to the possible internal coupling relationship between degradation of the internal photoelectric conversion unit and the increase in the off-state leakage current of the output-side power MOSFET.