Sea level failures of power MOSFETs displaying characteristics of cosmic radiation effects

An investigation into the failure rate of Power MOSFETs with room temperature junctions has been performed at sea level covering a range of drain voltages up to 110% of device rating. Phenomenally high failures rates over 10% per week were recorded using a test arrangement where the devices were configured to block continuous forward DC voltage. The failure rates were found to be several orders of magnitude higher than the expected Arrhenius model rate and were found to have a maximum near room temperature. The data was found to exceed the estimated sea level Single Event Burnout and Single Event Gate Rupture described in recent space and avionics radiation research papers, at greater than 80% voltage stress. Experimental data and the test arrangements are described, along with an empirical equation for reliability prediction.