0.86 kV p-Si/(001)-Ga₂O₃ Heterojunction Diode

Abstract

In this work, we report a single crystalline p-Si/(001) <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 heterojunction diode fabricated using semiconductor grafting technology. The diode showed a breakdown voltage ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{V}_{\text {br}}{)}$ </tex-math></inline-formula> of ~0.86 kV, which is the highest breakdown voltage reported for Si/(001) Ga2O3 heterojunction diode to date. The average peak electric field ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{E}_{\text {m}}{)}$ </tex-math></inline-formula> was calculated to be >2 MV/cm near breakdown, while the 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> was measured to be 7.7 <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, corresponding to a power figure of merit of ~96 MW/cm2. Catastrophic breakdown is confirmed by optical microscope inspection. The turn on voltage ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{V}_{\text {on}}{)}$ </tex-math></inline-formula> of the diode was measured to be around 1.12 V, the on–off ratio was calculated to be <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$9\times 10^{{9}}$ </tex-math></inline-formula> at–2 and 2 V, and the ideality factor was extracted to be approximately 1.18. The band structure of the diode was analyzed, and C-V measurements were also performed to understand the trapping behavior at the Si/Ga2O3 interface.