Design of AC Power Cycling Test Setup for GaN HEMTs' Reliability Assessments

In this paper, an AC power cycling test setup is presented for realistic Gallium Nitride (GaN) reliability evaluation. The test system is designed to mimic the field operation and accelerate the aging process under field conditions. The modular design of the setup enables tests for different vendors' devices and easy measurement of electrical parameters. A drain-source voltage measurement circuit is implemented to calculate the on-state resistance with the sampled current, which is used for the junction temperature estimation. Various voltage, current, and temperature stress can be controlled to stress the device for different switching scenarios, which provides data for health monitoring and lifetime estimation. Finally, a prototype is built to verify all theoretical considerations. From the experimental results, it is observed that the temperature swing varies for different phase angle operations, which is because of the difference in the power loss distribution.