Vth Adjustable p-Channel GaN FinFET for Complementary Logic Integration

In this paper, we report an oxygen plasma treatment method capable of effectively modulating threshold voltage (Vth,p) of p-type GaN Fin field-effect transistors (FET). p-FET with a fin width of 40nm exhibits excellent overall performance after treatment: Vth,p = −1.1V, subthreshold swing = 174mV/dec, Ion/Ioff ration = 2×10⁷, and Ion = ~55mA/mm. Moreover, on the same platform, this p-type device fabrication process can be effectively integrated with the enhancement-mode n-FET, culminating in the successful realization of an all-GaN complementary logic (CL) inverter. Operating at Vth,n = 1.4V, Vth,p = −1.1 V, and voltage supply = 2.5V, this CL inverter demonstrates steep transition characteristics and remarkably low energy consumption.