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 107.7 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.更多还原

【Abstract】 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.更多还原