Bipolar p-FET with Enhanced Conduction Capability on E-mode GaN-on-Si HEMT Platform

a bipolar p-FET (BiPFET) structure is proposed to enhance the conduction capability of GaN-based p-channel transistors that is limited by the intrinsically low hole mobility. In the BiPFET, a n-/p-/n-GaN (NPN) bipolar stack is depolyed at the drain side of a conventional p-FET, amplifying the conduction current with electrons serving as the majority carriers, which possess much higher mobility than holes. By matching the NPN stack with p-FET, the drain current density increases by 17 times compared to the conventional p-FET, exceeding 100 mA/mm. Meanwhile, the device control logic, high I
ON
/I
OFF
ratio and low gate leakage current of the p-FET are also well preserved.