Tribological properties of diamond-like carbon films deposited by pulsed laser arc deposition

A novel method, pulsed laser arc deposition combining the advantagesof pulsed laser deposition and cathode vacuum arc techniques, wasused to deposit the diamond-like carbon (DLC) nanofilms withdifferent thicknesses. Spectroscopic ellipsometer, Auger electronspectroscopy, x-ray photoelectron spectroscopy, Raman spectroscopy,atomic force microscopy, scanning electron microscopy andmulti-functional friction and wear tester were employed toinvestigate the physical and tribological properties of the depositedfilms. The results show that the deposited films are amorphous andthe sp$^{2}$, sp$^{3}$ and C--O bonds at the top surface of the filmsare identified. The Raman peak intensity and surface roughnessincrease with increasing film thickness. Friction coefficients areabout 0.1, 0.15, 0.18, when the film thicknesses are in the range of17--21~nm, 30--57~nm, 67--123~nm, respectively. This is attributed tothe united effects of substrate and surface roughness. The wearmechanism of DLC films is mainly abrasive wear when film thickness is in the range of 17--41~nm, while it transforms to abrasiveand adhesive wear, when the film thickness lies between 72 and 123~nm.