Enhancement mode gallium nitride transistor reliability

The industry´s understanding of the reliability of GaN transistors has continued to grow with positive results. In addition to the publication of several reliability reports [1-7] showing excellent performance across a wide set of operating conditions, in this paper we develop a more general understanding of commercially available enhancement mode gallium nitride transistors´ primary failure modes under voltage and temperature stress. Large populations were tested from multiple device lots in both high temperature gate bias (HTGB) and high temperature reverse bias (HTRB). The first section of this paper reports on the reliability qualification of EPC´s eGaN® FETs under a wide variety of stress conditions. The second section reports on the failure rate predictions using acceleration factors derived by stressing devices outside of normal operating conditions. In the last section, we discuss the reliability advantages of wafer level chipscale (WLCS) packaging compared to conventional MOSFET packages.