3.8-MV/cm Breakdown Strength of MOVPE-Grown Sn-Doped <tex-math notation="LaTeX">β </tex-math> -Ga₂O₃MOSFETs

A Sn-doped (100) <tex-math notation="LaTeX">β </tex-math> -Ga 2 O 3 epitaxial layer was grown via metal–organic vapor phase epitaxy onto a single-crystal, Mg-doped semi-insulating (100) <tex-math notation="LaTeX">β </tex-math> -Ga 2 O 3 substrate. Ga 2 O 3 -based metal–oxide–semiconductor field-effect transistors with a 2- <tex-math notation="LaTeX">μ m </tex-math> gate length ( <tex-math notation="LaTeX">LG) </tex-math> , 3.4- <tex-math notation="LaTeX">μ m </tex-math> source–drain spacing ( <tex-math notation="LaTeX">LSD) </tex-math> , and 0.6- <tex-math notation="LaTeX">μ m </tex-math> gate–drain spacing ( <tex-math notation="LaTeX">LGD) </tex-math> 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.