We have investigated high sp2 content intrinsic and sulfur doped nanocrystalline diamond films to study field emission properties by electron emission microscopy operated in different modes. Electron emission microscopy enables real time imaging of the electron emission from a surface with a lateral resolution of ∼15 nm. The nanocrystalline intrinsic diamond films exhibit electron emission at room temperature from localized emission sites with weak temperature dependence, and a density of ∼103-104/cm2. In contrast, sulfur doped diamond films show similar emission characteristics at room temperature, but at elevated temperatures the emission significantly increases from the localized regions and a thermionic component is identified in the I / V dependence. We discuss the role of S-donor states to explain the enhanced emission of the S-doped nanocrystalline diamond.
- Field emission
- Plasma CVD
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Mechanical Engineering
- Materials Chemistry
- Electrical and Electronic Engineering