Investigation of GaN HEMT Degradation in High Temperature Power Electronics Using Application Level Reliability Test

Abstract

Extreme environmental and high-power density applications, such as those in oil and gas industry, rely on power electronic circuits to drive sensors and control systems. These circuits are often subjected to harsh thermal conditions and must demonstrate high reliability to ensure uninterrupted operation. Gallium nitride (GaN) based semiconductor switches offer several advantages over conventional silicon (Si) devices, including a higher breakdown electric field and superior electron mobility, enabling more efficient and compact power electronics. However, as a relatively new technology with immature epitaxial processes, GaN reliability remains a critical concern, particularly in applications where unexpected downtime can lead to substantial economic losses. In high temperature environments, this challenge is further amplified by the frequent need for devices to operate beyond their datasheet-specified limits. In this work we explore the reliability of different GaN power semiconductor technologies in these conditions using realistic test procedure that is very closer to an actual converter operation. Devices were stressed for extended durations of up to 1000 h with their static parameters continuously monitored. The collected data were analyzed to identify failure modes and their underlying root causes, providing insights into the robustness of GaN devices under extreme condition.