High Performance β-Ga2O3 Nano-membrane Field Effect Transistors on a High Thermal Conductivity Diamond Substrate

To suppress severe self-heating under high power density, we herein demonstrate top-gate nano-membrane ${\beta }$ -gallium oxide ( ${\beta }$ -Ga2O3) field effect transistors on a high thermal conductivity diamond substrate. The devices exhibit enhanced performance, with a record high maximum drain current of 980 mA/mm for top-gate ${\beta }$ -Ga2O3 field effect transistors and 60% less temperature increase from reduced self-heating, compared to the device on a sapphire substrate operating under identical power density. With improved heat dissipation, ${\beta }$ -Ga2O3 field effect transistors on a diamond substrate are validated using an ultrafast high-resolution thermoreflectance imaging technique, Raman thermography, and thermal simulations.