An energy-band modulated p-GaN/InGaN/AlN p-channel MESFET with high ION/IOFF ratio and steep subthreshold swing

In this work, we report on the high-performance p-GaN/InGaN/AlN multi-heterostructure p-channel metal-semiconductor field effect transistors (MESFETs) with energy-band modulated quantum well-like InGaN channel and low work function metal tungsten (W) as the gate material. A negative threshold voltage (V-TH) of -0.35 V is achieved by precisely controlling the self-aligned etching depth at the active region. Benefiting from the enhanced hole confinement, the I-ON/I-OFF ratio and subthreshold swing of the fabricated-channel MESFET are extracted to be 1.2 x 10(7) and 66 mV/dec, respectively, at room temperature. The idealized Schottky interface with TMAH and post-gate-annealing treatment shows an ultra-low voltage hysteresis of 0.08 V extracted at subthreshold area in the dual-sweep transfer curves.