Electron Field Emission Properties of Diamond

ABSTRACTWe have developed both experimental and numerical methods to collect and analyze field emission data from diamond samples. The diamond emitters are either films prepared by low pressure chemical vapor deposition (CVD) or powders synthesized by traditional high pressure high temperature (HPHT) processes. We established a strong correlation between the electric field required for emission and the defect densities in undoped or p-type doped diamond. We further found that ultrafine diamond particulate emitters offer substantially enhanced electron field emission properties at low electric fields compared to CVD diamond emitters. When subject to appropriate processing schemes, the particulate diamond emitters exhibit extremely low emission fields, typically 1-5 V/μm for a current density of 10 mA/cm2. These are believed to be the lowest-voltage field emitters ever reported.