Ruggedness and reliability of GaN HEMT

In this paper, we reported evaluation results of our L/S-band GaN HEMT, especially focusing on ruggedness and reliability. In terms of ruggedness, we demonstrated GaN HEMT had 3-terminal breakdown voltage of 250 V and sufficiently wide area of safe operation (ASO) at 200 degC. Simulated peak drain-source voltage of an inverse class-F operation reached 160 V, and 3-terminal breakdown voltage was good enough at 250 V to cope with simulated maximum drain-source voltage. In addition, we carried out 2-type RF stress tests to evaluate ruggedness of GaN HEMT. One is VSWR ruggedness, the other is RF step stress test at stress level from 5 dB to 13 dB gain compression level. No destructive failures and degradations have been observed under both tests. In terms of reliability, we carried out DC-HTOL test for 5000 hours, MTTF was estimated 1.07 × 10⁶ hours at 200 degC. These results show our GaN HEMT has good enough ruggedness and reliability for high power applications.