Toward Unusual-High Hole Mobility of p-Channel Field-Effect-Transistors.

Abstract

The relative low hole mobility of p-channel building block device challenges the continued miniaturization of modern electronic chips. Metal-semiconductor junction is always an efficient strategy to control the carrier concentration of channel semiconductor, benefiting the carrier mobility regulation of building block device. In this work, complementary metal oxide semiconductor (CMOS)-compatible metals are selected to deposit on the surface of the important p-channel building block of GaSb nanowire field-effect-transistors (NWFETs), demonstrating the efficient strategy of hole mobility enhancement by metal-semiconductor junction. When deposited with lower work function metal of Al, the peak hole mobility of GaSb NWFET can be enhanced to as high as ≈3372 cm2 V-1 s-1 , showing three times than the un-deposited one. The as-studied metal-semiconductor junction is also efficient for the hole mobility enhancement of other p-channel devices, such as GaAs NWFET, GaAs film FET, and WSe2 FET. With the enhanced mobility, the as-constructed CMOS inverter shows good invert characteristics, showing a relatively high gain of ≈18.1. All results may be regarded as important advances to the next-generation electronics.