Two year reliability validation of GaN power semiconductors in low voltage power electronics applications

Abstract

This paper presents a reliability analysis of GaN HFETs under typical operating conditions. The GaN HFETs are operated in a low voltage point of load converter for two years of continuous operation. The power devices are regularly characterized to observe any component degradation, such as an increase in on-resistance or device failures. It is observed that the GaN HFETs undergo a phenomenon known as dynamic Rds(on) which is inherent to GaN HFETs. This effect is caused by a buildup of trapped electrons in the epitaxial layer over time. Over the course of two years of continuous operation, no other significant device degradation or failure has been observed. It is important to analyze reliability of GaN HFETs, as well as other WBG semiconductors, to promote industry adoption of these devices. The results presented show zero device failures and only minor performance degradation over the span of two years, and are promising for WBG semiconductor acceptance in the power industry.