Atmospheric Neutron Single-Event Burnout in Vertical Double-Diffused Metal-Oxide-Semiconductor (VDMOS) Devices

This study investigates the single-event burnout (SEB) mechanisms of 800 V Vertical Double-Diffusion Metal-Oxide-Semiconductor (VDMOS) devices using the China Spallation Neutron Source (CSNS) Atmospheric Neutron Irradiation Spectrometer. By combining experimental irradiation with a coupled Geant4-TCAD simulation framework, we establish a quantitative link between the atmospheric neutron spectrum and device failure. The study identifies that secondary Carbon and Boron ions generated via nuclear reactions are the primary drivers of SEB. While confirming the voltage-dependent nature of SEB, our results specifically determine a critical failure threshold of 610 V for this technology node under atmospheric spectra. Furthermore, the simulation reveals distinct sensitivity mechanisms: the neck region is dominated by LET sensitivity from high-Z recoils, while the P-body region is governed by the penetration depth of lighter ions. This work provides essential baseline data for the CSNS facility and offers a validated theoretical methodology for predicting terrestrial neutron reliability.