Effect of thin metal coatings in nanoscale on field emission characteristics of nitrogen-incorporated nanocrystalline diamond films is examined with different metal species and thicknesses. The films show minimal change in surface morphology by coating a thin layer of Ag, Au, and In and consist of fine grains with sizes ranging from 10 to 20 nm depending upon the metal species and thickness. While the emission turn-on field is increased slightly to 3.6 Vμm −1 with very small thicknesses of the metals, it is decreased toward 2.5 Vμm −1 typical of a non-coated film with increasing thickness of the metals up to a few nm. The field enhancement factor related to the surface morphology of the films gives stronger effects on emission performance than the effective barrier height related to the work function of the metals. The Ag-coated film shows higher emission current stability than the non-coated film for duration up to 13 h.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials