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 107.7 cm2 v-1 s-1, and a dramatic decrease of subthreshold swing from8.4 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.
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 107.7 cm2 v-1 s-1, and a dramatic decrease of subthreshold swing from8.4 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.
基金
Supported by the National Natural Science Foundation of China under Grant Nos 61474027 and 61774041
