Performance Characterization, Repeatability, and Consistency of X-Band GaN HEMTs Prior to High Temperature RF Reliability Testing

This paper reports the measured performance results on over 50 discrete GaN HEMTs mounted in high temperature RF/DC test fixtures capable of testing at > 250degC. The RF and DC parameters presented are prior to burn-in and accelerated life testing. Typical device performance variation from room temperature to 250degC is shown. The discussion focuses on the repeatability and consistency of the test fixture concept as well as the performance achieved by state-of-the art GaN devices. The highlighted performance parameters includes: gate-bias level and consistency; measured RF power output at 1dB compression; measured RF saturated power; measured power added efficiency (PAE); and realized power density in W/mm. This work demonstrates a procedure to address a major issue surrounding the difficulty of implementing a high temperature RF lifetest program