Characterization of silicon-stabilized amorphous hydrogenated carbon

The characterization of a modified form of diamondlike carbon, referred to as silicon-stabilized amorphous hydrogenated carbon (Si-AHC), is described. Auger electron spectroscopy, electron probe microanalysis, solid-state nuclear magnetic resonance, Raman scattering, nuclear reaction analysis, and optical absorption spectroscopy were used to determine chemical composition and to monitor structural changes due to the addition of silicon. Hardness, density, residual stress, and tribological properties of AHC and Si-AHC are compared. The Si-AHC coatings show much lower stress, a friction coefficient that is insensitive to moisture, an increase in optical gap compared to AHC, improved thermal stability, and equivalent hardness and wear. Some automotive applications are discussed.