Investigation of β-Ga2O3 MOSFET With Double Drift Layers by TCAD Simulation

In this article, we have proposed and analyzed a novel $\beta $ -phase gallium oxide ( $\beta $ -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 ( ${d}$ ) 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 ${d}$ 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 ${d}$ values of 0.5 and $3.5~\mu \text{m}$ , respectively. Compared to the control device with single drift layer, the designed construction achieved an excellent PFOM and reduced specific ON-resistance ( ${R} _{{\text {on},\text {sp}}}$ ), while maintaining an unaltered or appreciable breakdown voltage ( ${V} _{{\text {br}}}$ ). This proposed structure provides a new way to achieve high performance for $\beta $ -Ga2O3 MOSFETs.