High-Energy Proton and Atmospheric-Neutron Irradiations of SiC Power MOSFETs: SEB Study and Impact on Channel and Drift Resistances

Abstract

Accelerated single event burnout (SEB) tests with 200 MeV protons and atmospheric neutrons were performed for commercial silicon carbide (SiC) power MOSFETs with different architectures (i.e., planar gate, asymmetric trench, and symmetric trench). The average electric fields over the depletion layer width and the electric field distributions are reported for the tested conditions and compared for the three architectures, confirming the necessity of a lower de-rating for the trench design to protect from SEB, compared to planar ones. In addition to the epitaxial layer design, the influence of other design parameters on the SEB threshold is discussed. Finally, to investigate the presence of precursor damage in the pre-SEB region, a methodology is presented and used to study the radiation-induced degradation of the channel and drift resistances of devices that survived the SEB tests.