Research on the On-orbit Reliability Prediction Method of SiC MOSFET

This study investigates a predictive method for assessing the on-orbit reliability of silicon carbide power MOSFETs under single-event burnout (SEB) conditions in space environments. Ion-induced single-event effects can escalate leakage currents across the mission cycle, underscoring the imperative to guarantee component reliability in orbit. SiC power MOSFETs meet typical reliability measures for space applications. Firstly, the damage effects of SiC power MOSFETs are analyzed. Heavy-ion irradiation often initiates SEB at voltages 50% or less than the specified breakdown threshold. Subsequently, failure rates for 1200 V devices in space are calculated using experimental data and the anticipated heavy-ion linear energy transfer (LET) spectrum. Finally, a reliability prediction method for SiC power MOSFET SEB is developed. The SEB reliability of SiC power MOSFETs is predicted for various Earth orbits and mission durations, considering different thicknesses of aluminum shielding materials. The operating voltage dictates the minimum linear energy transfer (LET) threshold for particles that lead to SEB, necessitating their consideration within the environmental distribution. The overall environmental distribution of mission fluence is also determined by mission duration and shielding. This approach may be utilized to assess the likelihood of failure due to a destructive event when the device’s critical linear energy transfer (LET) threshold is adequately low for the expected mission environment.