Commercial-off-the-shelf algan/gan hemt device reliability study after exposure to heavy ion radiation

Abstract

The reliability of commercial-off-the-shelf (COTS) GaN HEMTs was studied after irradiation using heavy ions of Neon (Ne), Silicon (Si), and Argon (Ar). Devices were exposed to heavy ions at a flux of ~1.8e4 ions/cm2-sec to a fluence of 1.5e5 ions/cm2 and DC characterization measurements taken immediately after exposure exhibited no change. Additionally, no change in device performance was observed in DC or RF characterization taken prior to RF stress testing. Infrared (IR) and electroluminescence (EL) characterization was conducted before irradiation, post irradiation, and following stress testing to assess changes in emissions. After heavy ion exposure, irradiated devices and non-irradiated devices were subjected to an RF stress test at an elevated baseplate temperature. Results imply the irradiated devices degraded at a different rate than the non-irradiated device which suggests potential for confounding effects on long term reliability from heavy ion exposure. Future studies should be conducted using larger sample sizes and different radiation sources to determine if additional stress testing is required for GaN HEMT space qualification.