Investigation of <i>β</i>-Ga<sub>2</sub>O<sub>3</sub> MOSFET With Double Drift Layers by TCAD Simulation
Xiaole Jia, Yibo Wang, Cizhe Fang, Haodong Hu, Yan Liu, Zheng‐Dong Luo, Yue Hao, Genquan Han
Abstract
In this article, we have proposed and analyzed a novel <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> -phase gallium oxide ( <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 field-effect transistor (MOSFET) with double drift layers (DDLs) located in the gate to drain region. This device has a highly doped drift (HDD) layer that is positioned below a lowly doped drift layer, which are connected in parallel. The HDD is located at a distance ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${d}$ </tex-math></inline-formula> ) from the gate metal to ensure optimal breakdown performance. We extensively investigated how the doping concentration and thickness of the HDD, with both small and large <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${d}$ </tex-math></inline-formula> values, affect the device’s electrical characteristics. Our simulations revealed that the proposed device achieved a decent power figure-of-merit (PFOM) of 582.0 and 461.2 MW/cm2 at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${d}$ </tex-math></inline-formula> values of 0.5 and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$3.5~\mu \text{m}$ </tex-math></inline-formula> , respectively. Compared to the control device with single drift layer, the designed construction achieved an excellent PFOM and reduced 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">${R} _{{\text {on},\text {sp}}}$ </tex-math></inline-formula> ), while maintaining an unaltered or appreciable 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">${V} _{{\text {br}}}$ </tex-math></inline-formula> ). This proposed structure provides a new way to achieve high performance for <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 MOSFETs.