  We have demonstrated that depletion/enhancement-mode b-Ga2O3 on insulator
field-effect transistors can achieve a record high drain current density of
1.5/1.0 A/mm by utilizing a highly doped b-Ga2O3 nano-membrane as the channel.
b-Ga2O3 on insulator field-effect transistor (GOOI FET) shows a high on/off
ratio of 1010 and low subthreshold slope of 150 mV/dec even with 300 nm thick
SiO2. The enhancement-mode GOOI FET is achieved through surface depletion. An
ultra-fast, high resolution thermo-reflectance imaging technique is applied to
study the self-heating effect by directly measuring the local surface
temperature. High drain current, low Rc, and wide bandgap make the b-Ga2O3 on
insulator field-effect transistor a promising candidate for future power
electronics applications.
