Experimental analysis of the gate-leakage-induced failure mechanism in GaN HEMTs

摘要

This work investigates the electro-thermal behavior and failure mechanism of a 600 V depletion-mode GaN HEMT by experimental analysis and numerical thermal simulations. For this device, the positive temperature coefficient of the drain-gate leakage current can lead to the formation of hot spots. This localized thermal runaway which ultimately results in a breakdown of the inherent drain-gate junction is found to be the dominant cause of failure.