Characterization of Plasma-Deposited Amorphous Carbon Films

摘要

Thin carbon films of approx.600 A have been deposited on Si <111> wafers by striking an rf discharge in gas mixtures of hydrogen and methane. The deposition rate increased with increasing methane fraction. The peak rate was approx.1 A/sec at an applied power density of 0.4 W cm sup -2 . The films, with an average density of 2.54 gm cm sup -3 , are amorphous in nature but exhibit broad diffraction maxima corresponding to interplanar spacings of 2.05A and 1.15A. Measurements of hydrogen concentration in the films showed that the hydrogen at. % increased from 30% to 40% as the hydrogen fraction in the feed gas increased. By using a D sub 2 -CH sub 4 , we were also able to deduce that hydrogen molecules can be a large source of hydrogen trapped in the films. (ERA citation 12:043633)