Strong dependence of IR absorption in a-SiC:H dc magnetron sputtered thin films on H2 partial pressure

The usual method for deposition of hydrogenated amorphous silicon carbide (a-SiC:H) thin films is the radio-frequency (rf) magnetron sputtering method in an Ar and CH4 mixture. In this paper, we present a dc magnetron sputtering method for a-SiC:H thin films. The films were deposited in a mixture of CH4, H-2 and Ar. The target used was polycrystalline Si. We found that the hydrogen partial pressure has a decisive contribution to the film composition. The presence of hydrogen leads to dominant Si-C bonds in film composition while the absence of molecular hydrogen leads to a dominant C-H bonds in film composition. Also, the total pressure during the deposition was found to play an important role for the film composition. (C) 2001 Elsevier Science B.V. All rights reserved.