Accelerated thermal degradation testing of GAN HEMTs under high-temperature stress

Gallium Nitride (GaN) high-electron-mobility transistors (HEMTs) are having increased applications in high-power and high-frequency conversion areas due to their superior switching speed, high breakdown voltage, and low conduction losses. Despite their advantages, GaN HEMTs are prone to performance degradation when exposed to elevated temperatures and electrical stress over long durations. This study aims to investigate the degradation behavior of commercial EPC90122 GaN HEMT devices under controlled high-temperature operating conditions. Accelerated degradation testing is conducted by heating the devices within a thermal chamber at 150 °C under high-current stress. An external circuit is connected to the switch node of the HEMT device to record on-state drain-source voltage, VDS (on), across a shunt resistor and the corresponding drain current, enabling the calculation of on-state drain-source resistance, RDS (on), throughout the stress period using offline measurement methods. The observed 10–25% increase in RDS (on) indicates progressive degradation likely associated with charge trapping and thermally induced mobility reduction. Results show that RDS (on) is a meaningful degradation indicator, supporting both reliability assessment and the development of prognostics and health management strategies for GaN power devices. The measurement approach allows researchers to continuously track the device health without applying intrusive and destructive test configurations. The findings and methodology also establish the foundation for future remaining useful life prediction and data driven prognostics model development, guiding the design of more robust GaN-based power electronics with improved thermal management and reliability margins.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Systems & Entrepreneurial Engr

Grantor

University of Illinois Urbana-Champaign

Year dc:date

2025

Author dc:creator

• Luo, Yanbin

Contributors dc:contributor

• Wang, Pingfeng

• Gallium Nitride (GaN) HEMTs
• Accelerated Thermal Degradation
• High-Temperature Reliability Testing
• On-State Resistance (RDS(on))
• Prognostics and Health Management (PHM)

Statement dc:rights

• Copyright 2025 Yanbin Luo

Language dc:language

en

Handle dc:identifier

https://hdl.handle.net/2142/132605

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/132605