Improved Electrical Characteristics of Gallium Oxide/P-Epi Silicon Carbide Static Induction Transistors with UV/Ozone Treatment Fabricated by RF Sputter

In this study, static induction transistors (SITs) with beta gallium oxide (β-Ga O ) channels are grown on a p-epi silicon carbide (SiC) layer via radio frequency sputtering. The Ga O films are subjected to UV/ozone treatment, which results in reduced oxygen vacancies in the X-ray photoelectron spectroscopy data, lower surface roughness (3.51 nm) and resistivity (319 Ω·cm), and higher mobility (4.01 cm V s ). The gate leakage current is as low as 1.0 × 10 A at V = 10 V by the depletion layer formed between n-Ga O and p-epi SiC at the gate region with a PN heterojunction. The UV/O -treated SITs exhibit higher (approximately 1.64 × 10 times) drain current (V = 12 V) and on/off ratio (4.32 × 10 ) than non-treated control devices.