3.8-MV/cm Breakdown Strength of MOVPE-Grown Sn-Doped β-Ga2O3 MOSFETs

A Sn-doped (100) beta-Ga2O3 epitaxial layer was grown via metal-organic vapor phase epitaxy onto a single-crystal, Mg-doped semi-insulating (100) beta-Ga2O3 substrate. Ga2O3-based metal-oxide-semiconductor field-effect transistors with a 2-mu m gate length (LG), 3.4-mu m source-drain spacing (LSD), and 0.6-mu m gate-drain spacing (LGD) were fabricated and characterized. Devices were observed to hold a gate-to-drain voltage of 230 V in the OFF-state. The gate-to-drain electric field corresponds to 3.8 MV/cm, which is the highest reported for any transistor and surpassing bulk GaN and SiC theoretical limits. Further performance projections are made based on layout, process, and material optimizations to be considered in future iterations.