A method for forming a coating over a surface is disclosed. The method comprises depositing over a surface, a hybrid layer comprising a mixture of a polymeric material and a non-polymeric material. The hybrid layer may have a single phase or comprise multiple phases. The hybrid layer is formed by chemical vapor deposition using a single source of precursor material. The chemical vapor deposition process may be plasma-enhanced and may be performed using a reactant gas. The precursor material may be an organo-silicon compound, such as a siloxane. The hybrid layer may comprise various types of polymeric materials, such as silicone polymers, and various types of non-polymeric materials, such as silicon oxides. By varying the reaction conditions, the wt % ratio of polymeric material to non-polymeric material may be adjusted. The hybrid layer may have various characteristics suitable for use with organic light-emitting devices, such as optical transparency, impermeability, and/or flexibility.