STRESSES IN DIAMOND-LIKE CARBON-FILMS

Internal stresses have been measured in diamond-like carbon (DLC) film s deposited by d.c. plasma assisted chemical vapor deposition from met hane, acetylene, or cyclohexane, and in nitrogen containing DLC films deposited from acetylene, or cyclohexane and nitrogen. The total hydro gen content in the films and the fraction of bound hydrogen have been analyzed by forward recoil elastic scattering and Fourier transform in frared spectroscopy respectively. It was found that in pure DLC films the stresses increase with increasing fraction of unbound hydrogen. Th e highest compressive stresses were obtained in the films deposited fr om methane and the lowest stresses in films deposited from cyclohexane . In the nitrogen containing DLC films the stresses decrease with incr easing nitrogen content in the films. Stresses as low as 0.22 GPa were obtained in the films deposited from cyclohexane and nitrogen at a ra tio of 1/15 in the plasma.