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

Abstract

In this work, we have achieved novel lateral enhancement-mode (E-M) and depletion-mode (D-M) <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula> -Ga2O3 metal-oxide-semiconductor junction field-effect- transistors (MOS-JFETs) featuring a low gate leakage current ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{I}_{{\text {G}}}$ </tex-math></inline-formula> ) and a large gate swing. Ascribing to the high-quality SiO2 layer above the P-NiO <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{{{\text {X}}}}$ </tex-math></inline-formula> /N-Ga2O3 heterojunction (HJ), the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{I}_{G}$ </tex-math></inline-formula> was suppressed for over 6 orders of magnitudes when compared with the heterojunction FET (HJ-FET). An off-state drain current of ~ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$10^{-{7}}$ </tex-math></inline-formula> 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 ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{L}_{{\text {SD}}}$ </tex-math></inline-formula> ) of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$12 ~\mu \text{m}$ </tex-math></inline-formula> demonstrates a breakdown voltage (BV) of 1.32 kV and specific on-resistance ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{R}_{{\text {on},\text {sp}}}$ </tex-math></inline-formula> ) of 4.4 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{m}\Omega \cdot $ </tex-math></inline-formula> cm2, delivering a high Baliga’s power figure of merit (PFOM) of 405 MW/cm2. Due to the potential of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula> -Ga2O3 MOS-JFET in power electronics, these findings offer a compel ling pathway for future high-power and high-efficiency systems.