PHYSICAL AND TRIBOLOGICAL PROPERTIES OF RAPID THERMAL ANNEALED DIAMOND-LIKE CARBON-FILMS

This paper reports the physical characterization and tribological properties of diamond-like carbon (DLC) and rapid thermal annealed (RTA) DLC films. Amorphous DLC films were deposited by the direct ion beam deposition technique using methane ions. Rapid thermal annealing (RTA) of the films was performed at several fixed temperatures (350, 400, 500, 600, 700, 800, 900 and 1000-degrees-C) in a nitrogen atmosphere for 2 min. The films were then characterized by proton recoil detection analysis for hydrogen content, Rutherford backscattering for carbon content and Raman spectroscopy for structural change. The hydrogen content of the DLC films remains constant at 30 at.% in the RTA temperature range 25-500-degrees-C, decreases rapidly from 25% to 9% in the range 600-800-degrees-C and finally remains at 5% in the range 900-1000-degrees-C. The Raman spectra of the DLC films do not change in the RTA temperature range 25-400-degrees-C and begin to show the appearance of crystalline graphitic carbon above 500-degrees-C. The coefficients of friction of the DLC films do not change significantly with the RTA process; however, the wear factors are strongly dependent on the annealing temperature and the moisture in the environment.