Preparation of amorphous carbon thin films containing nitrogen by plasma pulsed deposition method

摘要

Amorphous carbon thin films containing nitrogen were deposited by the radio frequency (13.56MHz) self-bias method, using acetonitrile as a starting material. The effects of the deposition conditions and the behavior of nitrogen atoms during the film depositions were investigated in detail with controlling the deposition temperature by the plasma pulsed deposition technique. The results show that the nitrogen doped high quality films are prepared under only the deposition conditions for higher r.f. powers and higher deposition temperatures, compared to undoped hard amorphous carbon thin films. Furthermore, the incorporation of nitrogen reduces the internal film stress without significant modification of the film hardness. X-ray photoelectron spectroscopy indicates that nitrogen concentrations in the carbon films decrease with increasing deposition temperatures and r.f. powers. Infrared absorption and Raman spectroscopy suggest that nitrogen atoms are incorporated into the nitrile groups and into the graphite-like carbon clusters and/or into the random network structures as the C=N bonds.