Field Emission Properties of Tungsten Carbide Thin Films Formed on Tungsten Tips

摘要

Field emission patterns of tungsten carbide film formed on a tungsten tip surface were observed after the tungsten tip was annealed at appropriate experimental conditions. Current voltage characteristic of the tungsten carbide film was measured in situ, and its work function was self-consistently calculated to be 3.73 eV according to the Fowler-Nordheim theory. Compared with clean tungsten tips, the work function of the tungsten tip coated with tungsten carbide film is lowered and the emission current stability is improved, which indicates the usefulness of tungsten carbide in the development of field emitters.