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 (V-TH), low specific on resistance (R-ON,(SP)) and high output current (I-D(max)). The excellent channel control capability offered by tri-gate structure led to a reduced OFF-state leakage current (I-OFF), 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 mu m, a hard V-BR of 2050 V were achieved, along with a low R-ON,R-SP of 2.42 m Omega.cm(2), which corresponds to a state-of-the-art figure of merit (FOM) of 1.73 GW/cm(2). These results unveil the electronics applications.