Excellent field emission properties of VO2(A) nanogap emitters in air

Abstract

VO₂(A) emitters with a 10 nm gap between the emitter and the collector were fabricated with the aid of focused ion beam etching. Due to the extremely small electrode gap, high emission currents (upto 53 μA at 1 V) and excellent emission stability were achieved in air with a turn-on voltage as low as 0.46 V. The field emission behavior exhibits a temperature dependence, which is attributed to the temperature-induced reduction of the work function. This work provides a practical way to ease the demand of high vacuum and high operation voltage in vacuum devices, which is helpful for developing low-power nanoscale vacuum devices.