【International Papers】Gallium Oxide Heterojunction Diodes for 400C High Temperature Applications

      Researchers from the National Renewable Energy Laboratory have published a dissertation titled " Gallium Oxide Heterojunction Diodes for 400C High Temperature Applications " in Wiley.

Abstract

      β-Ga₂O₃ based semiconductor devices are expected to have significantly improved high-power and high-temperature performance due to its ultra-wide bandgap of close to 5 eV. However, the high-temperature operation of these ultra-wide-bandgap devices is usually limited by the relatively low 1-2 eV built-in potential at the Schottky barrier with most high-work-function metals. Here, we report heterojunction p-NiO/n-β-Ga₂O₃ diodes fabrication and optimization for high-temperature device applications, demonstrating a current rectification ratio (I_ON/I_OFF) of more than 10⁶ at 410°C. The NiO heterojunction diode can achieve higher turn-on (V_ON) voltage and lower reverse leakage current compared to the Ni-based Schottky diode fabricated on the same single crystal β-Ga₂O₃ substrate, despite charge transport dominated by interfacial recombination. Electrical characterization and device modeling show that these advantages are due to a higher built-in potential and additional band offset. These results suggest that heterojunction p-n diodes based on β-Ga₂O₃ can significantly improve high-temperature electronic device and sensor performance.

Paper Link：https://doi.org/10.1002/pssa.202300535