Optimization of normally-off β-Ga2O3 MOSFET with high Ion and BFOM: A TCAD study

A combination of recessed-gate and gate-field plate in lateral β-Ga2O3 metal–oxide–semiconductor field-effect transistor (MOSFET) is proposed in the Technology Computer Aided Design study to improve its ON resistance (RON) and breakdown voltage. Enhancement-mode (E-mode) is achieved by controlling the thickness of the recessed-gate. Lateral E-mode β-Ga2O3 MOSFET achieves a saturation current density near 120 mA/mm, ION/IOFF ratio ∼109, RON ∼91 Ω mm, and breakdown voltage of 1543 V. The optimized structure results in a prediction of a power figure-of-merit of 261 MW/cm2 in a horizontal E-mode β-Ga2O3 MOSFET.