Correlation between hardness and structure of carbon-nitride thin films obtained by reactive pulsed laser deposition

Carbon-nitride thin films were synthesized by reactive pulsed laser deposition from graphite targets in low-pressure nitrogen. X-Ray photoelectron spectroscopy and nanoindentation measurements were performed in order to establish a connection between the composition, structure and hardness of the obtained thin films. We studied the variation of the sp 3/sp 2 C bonded to N ratio with the increase of the N content of the thin layers. We found that the value of this ratio mainly determines the hardness of the carbon-nitride layers. The stability in time and/or under thermal heating of the CN bonds formed was also tested.