Mechanical characterization and tribological evaluation of ion-beam-assisted sputter coatings of carbon with nitrogen incorporation

Sputter coatings of carbon with nitrogen incorporation have been prepared b y ion-beam-assisted deposition on Si(lll) substrates. An amorphous structur e with tiny crystals in the coating has been observed and confirmed by fiel d-emission transmission electron microscopy. Analyses by X-ray photoelectro n spectroscopy and secondary-ion mass spectrometry have revealed that the l evel of nitrogen incorporation is about 10%, and the composition distributi on of both carbon and nitrogen atoms normal to the coating surfaces is homo geneous. A detailed Raman analysis has further shown that the proportion of sp(2) carbon bonds increases with the nitrogen acceleration energy. The in fluences of different nitrogen incorporation parameters and different coati ng thicknesses on the mechanical properties of carbon nitride coatings have been systematically characterized for the first time from the viewpoints o f surface roughness, nanoindentation hardness and internal stress. Finally, the tribological properties of ion-beam-assisted carbon nitride coatings h ave also been evaluated in terms of nitrogen incorporation and coating thic kness. (C) 2000 Elsevier Science S.A. All rights reserved.