Demonstration of the β-Ga₂O₃ MOS-JFETs With Suppressed Gate Leakage Current and Large Gate Swing

In this work, we have achieved novel lateral enhancement-mode (E-M) and depletion-mode (D-M) $\beta $ -Ga2O3 metal-oxide-semiconductor junction field-effect- transistors (MOS-JFETs) featuring a low gate leakage current ( $\text{I}_{{\text {G}}}$ ) and a large gate swing. Ascribing to the high-quality SiO2 layer above the P-NiO $_{{{\text {X}}}}$ /N-Ga2O3 heterojunction (HJ), the $\text{I}_{G}$ was suppressed for over 6 orders of magnitudes when compared with the heterojunction FET (HJ-FET). An off-state drain current of ~ $10^{-{7}}$ mA/mm was also achieved at elevated temperature (T) up to 200 °C, indicating strong thermal stability of our device. The depletion-mode (D-M) MOS-JFET with source-to-drain spacing ( $\text{L}_{{\text {SD}}}$ ) of $12 ~\mu \text{m}$ demonstrates a breakdown voltage (BV) of 1.32 kV and specific on-resistance ( $\text{R}_{{\text {on},\text {sp}}}$ ) of 4.4 $\text{m}\Omega \cdot $ cm2, delivering a high Baliga’s power figure of merit (PFOM) of 405 MW/cm2. Due to the potential of $\beta $ -Ga2O3 MOS-JFET in power electronics, these findings offer a compel ling pathway for future high-power and high-efficiency systems.