Raman Analysis of Amorphous Carbon Coatings Prepared By Hollow Cathodes At Moderate Pressure
Amorphous carbon coatings have been prepared using cylindrical and linear hollow cathode arrangements. The
deposition has been carried out in a hybrid PVD/PE-CVD mode using graphite cathodes and C2H2 reactive gas and Ar as the
carrier gas. Microstructure of the deposited coatings have been studied using Raman spectroscopy. The results show that
amorphous carbon films with sp3 fraction of less than 20% can be deposited. In the M-M linear hollow cathode system
increased C2H2 contents contribute to higher graphitic disorder. Higher deposition pressure promotes deposition of more
hydrogenated coatings at lower acetylene contents.
Index Terms- Amorphous carbon, hollow cathode, hybrid PVD/PE-CVD, Raman analysis