Performance Improvement in Hydrogenated Few-Layer Black Phosphorus Field-Effect Transistors

摘要

A capping layer for black phosphorus (BP) field-effect transistors (FETs) can provide effective isolation from the ambient air;however,this also brings inconvenience to the post-treatment for optimizing devices.We perform low-temperature hydrogenation on Al2 O3 capped BP FETs.The hydrogenated BP devices exhibit a pronounced improvement of mobility from 69.6 to 107.7cm2v-1s-1,and a dramatic decrease of subthreshold swing from 8.4 to 2.6 V/dec.Furthermore,high/low frequency capacitance voltage measurements suggest reduced interface defects in hydrogenated BP FETs.This could be due to the passivation of interface traps at both Al2 O3/BP and BP/SiO2 interfaces with hydrogen revealed by secondary ion mass spectroscopy.