Defect-engineered GaN high electron mobility transistors for enhanced radiation tolerance

Abstract: This study explores the radiation resilience of GaN high-electron-mobility transistors (HEMTs) under various preconditioning treatments—pristine, electro-pulsed, electrically overstressed, and ⁶⁰Co gamma-irradiated—with a focus on enhancing survivability in high-radiation environments. Key findings emphasize the gate region’s central role in radiation sensitivity, with increased defect concentrations leading to reduced sensitivity—as determined from reduced single-event transient intensities during pulsed-laser studies—and impacting charge-transport dynamics. Notably, the most sensitive region shifted as a function of bias state, with the drain side of the gate being most sensitive under negative gate bias and the source side under unbiased conditions due to two-dimensional electron gas disruptions. These insights clarify the mechanisms influencing radiation sensitivity in microelectronics and highlight the potential of defect and strain engineering to enhance the radiation hardness of GaN HEMTs across various operational states, providing valuable guidance for applications in space, defense, and other radiation-rich environments. Impact statement: The increasing deployment of electronic systems in extreme environments, such as space, defense, and high-energy physics, necessitates robust microelectronic devices capable of withstanding radiation-induced damage. This study explores the radiation resilience of gallium nitride high-electron-mobility transistors, a key technology in power electronics and radio-frequency applications, by investigating the interplay between defect engineering, strain modulation, and radiation response. By integrating advanced characterization techniques, including pulsed-laser single-event transient testing, photoluminescence spectroscopy, and electron-beam-induced current imaging, the research identifies critical regions of radiation sensitivity and reveals how preconditioning treatments, such as gamma irradiation and electro-pulsing, modulate defect profiles to enhance device robustness. These findings help to pave the way for future targeted design strategies to optimize the radiation hardness of electronics.