High-performance normally-off tri-gate GaN power MOSFETs

In this work, we present the investigation of the combination of gate recess and tri-gate structures to achieve high performance normally-off GaN-on-Si MOSFETs with high positive threshold voltage ( VTH), low specific on resistance ( RON,SP) and high output current ( ID
^max
). The excellent channel control capability offered by tri-gate structure led to a reduced OFF-state leakage current ( IOFF), higher ON/OFF ratio, smaller subthreshold slope ( SS) compared to similar planar and recessed-gate devices. With gate to drain length ( L
_GD
) of 20 μm, a hard VBR of 2050 V were achieved, along with a low RON,SP of 2.42 mΩ·cm
²
, which corresponds to a state-of-the-art figure of merit (FOM) of 1.73 GW/cm
²
. These results unveil the extraordinary prospects of tri-gate technology for future power electronics applications.