Study of the methane flow influence in the micro-tribology behavior of DLC coatings deposited by PECVD: a Raman analysis

This paper presents a Raman spectroscopy study of the influence of methane flow on the micro-tribological behavior of diamond-like carbon coatings deposited with an industrial plasma-enhanced chemical vapor deposition system. Results have shown a direct relationship between the methane flow and thickness of the coatings. The analysis of the Raman spectra and deposition parameters allowed establishing the influence of H content with the methane flow, the disorder level and estimation of the sp(3) fraction on the carbon coatings. The micro-tribology tests showed a strong dependence of the wear resistance and hardness with Raman parameters. The coating deposited at 72-sccm methane flow presented a thickness of 1.7 mu m and a sp(3) fraction of 0.33. This sp(3) fraction gave rise to a hardness of 24 GPa and an excellent wear resistance of 3.3 x 10(-6) mm(3) N-1 mm(-1) for this DLC coating. Wear tests showed a swelling in the wear profiles on this coating, which was associated with the occurrence of a re-hybridization process.

Automated summary

This study investigated the influence of methane flow on the micro-tribological behavior of diamond-like carbon coatings using Raman spectroscopy. The results showed a direct relationship between methane flow and coating thickness, and the analysis of Raman spectra helped establish the properties of the carbon coatings. Additionally, the study demonstrated a strong correlation between wear resistance and hardness with Raman parameters.