VERY LOW THRESHOLD ELECTRON FIELD EMISSION FROM AMORPHOUS CARBON FILMS WITH HYDROGEN DILUTION

Abstract

Hydrogenated amorphous carbon films were fabricated with and without hydrogen dilution in a small d.c bias-assisted plasma chemical vapor deposition system. It was found that the hydrogen dilution can reduce the sp 2/ sp 3 ratio in carbon films which results in blue shift of room temperature photoluminescence spectrum. The field emission characteristics were investigated by using parallel plates test configuration. A very low threshold electric field (~0.5 V/μm) was achieved from thin amorphous carbon film prepared with hydrogen dilution. The improvement to field emission property in the present carbon films was tentatively attributed to the field enhancement effect due to the electronic structure inhomogeneity of the carbon films and the reduction of the surface emission barrier due to the hydrogen termination.