Sb-doped SnO 2 wire: Highly stable field emitter

Abstract

Field emission investigations of a single Sb-doped SnO 2 wire synthesized by thermal evaporation have been carried out in conventional field emission geometry under ultrahigh vacuum. An onset field required to draw a current of 1 nA has been reproducibly observed to be 9.5×10 3 V/μm. A current density of 5.88×10 3 A/cm 2 has been drawn with an applied field of 2×10 4 V/μm. The Fowler–Nordheim plot, obtained from the current–voltage ( I– V) measurements, shows linear nature in accordance with the quantum mechanical tunneling phenomenon. The field enhancement factor has been estimated to be 26,500 cm −1, indicating that the emission is from the nanometric features of the Sb-doped SnO 2 wire. The current–time ( I– t) measurement shows high current stability without severe deviations from the initial set value of 1 μA.