Nitrogen doping of amorphous DLC films by rf plasma dissociated nitrogen atom surface bombardment in a vacuum

Interpretations of recent (1999) theoretical first principles calculations in the literature based on the density functional theory using the local de nsity approximation has led to suggestions that a low energy nitrogen surfa ce bombardment of amorphous carbon films should lead to a reduction in the work function of the films. By applying a low energy nitrogen flux generate d by a nitrogen plasma source to the surface of amorphous diamondlike carbo n (DLC, a-C:H) films prepared by plasma enhanced chemical vapour deposition (PEVCD) in a vacuum, relatively high non-bonded nitrogen doping levels hav e been observed compared with DLC films prepared by other methods reported in the literature. The amorphous DLC films have been characterised by X-ray photoelectron spectroscopy and Raman spectroscopy before and after nitroge n bombardment. This novel processing route is expected to have an impact on residual stress relief and the field emission properties of amorphous DLC.