Field emission from boron-doped polycrystalline diamond film at the nanometer level within grains

Surface morphology, conductivity, and field emission properties of boron-do ped polycrystalline diamond film have been studied using scanning tunneling microscopy, current imaging tunneling spectroscopy, and separation-voltage (S-V) spectroscopy focusing on the properties within a single grain. The e mission properties show significant spatial variations within single grains at the nanometer level. S-V spectroscopy provided direct values of the fie ld required for the emission from nanometer-sized structures at the surface . Strong correlation between surface conductivity and low-field emission ha s been found. The results suggest that the emission properties of the film on the nanometer level are determined by local hydrogen termination. (C) 20 00 American Institute of Physics. [S0003-6951(00)02634-6].