\b{eta}-Ga2O3 on Insulator Field-effect Transistors with Drain Currents Exceeding 1.5 A/mm and Their Self-heating Effect

TL;DR

This paper demonstrates high-performance ta-Ga2O3 on insulator FETs with record drain currents exceeding 1.5 A/mm, and investigates their self-heating effects using thermo-reflectance imaging, highlighting their potential for power electronics.

Contribution

It reports the first achievement of record high drain currents in ta-Ga2O3 on insulator FETs and introduces a novel thermo-reflectance imaging technique to study self-heating effects.

Findings

Drain current density exceeds 1.5 A/mm

High on/off ratio of 10^10 and low subthreshold slope of 150 mV/dec

Self-heating effects characterized by thermo-reflectance imaging

Abstract

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.