Hydrogenated amorphous silicon–carbon alloys obtained from Ar–SiH4–CH4 gas mixtures: Structural and transport properties

We study some transport and structural properties of a-SiC:H films deposited by glow discharge with silane/methane/argon mixtures in the so-called low power regime. We observe a degradation of the transport properties with increasing rf power density. This behavior is explained both by a disorder increase and by the incorporation of graphitic-like clusters. The photoluminescence efficiency at room temperature agrees with this conclusion. Such clusters are created by surface bombardment of Ar∗ or Ar+ species which, in a first stage, allow to increase the deposition rate.