  We present results of carbon coatings on metal substrates in cylindrical
hollow cathode (CHC) direct current magnetron sputtering. This is a new
technique of making amorphous carbon film in CHC magnetron sputtering from
regenerative sooting discharge. The carbon films are deposited on Cu and Al
substrates in Ne atmosphere and compared with the films of carbon soot on the
same materials produced from conventional arc discharge between graphite
electrodes at 80 Angstrom in He background. The films are characterized using
online emission, Raman, and Fourier transform infrared spectroscopy; X-ray
diffraction (XRD) and Scanning electron microscopy (SEM). Raman spectroscopy
reveals the existence of graphite and diamond like structures from arc
discharge while in CHC magnetron sputtering, graphite like structures are
dominant. XRD pattern from arc discharge show precipitates of Al4C3 of
rhombohedral and hexagonal types in nanometer ranges for aluminum sample and
probable formation of diamond and hexagonal carbon in copper whilst in
magnetron sputtering we get amorphous carbon films. SEM images of surface show
collection of loose agglomerates of carbon particles in arc discharge whereas
for magnetron sputtering structures are regular with smooth edges and fine
grains.
