Deposition rate and three-dimensional uniformity of RF plasma deposited SiOx films

The variation of power, pressure and O2/HMDSO ratio in an RF plasma was carried out to examine deposition rates and to optimize SiOx film properties for the coating of polymers. The deposition rate can mainly be increased with monomer gas flow, whereas it is independent of pressure. Pure HMDSO plasmas reveal different internal conditions and deposition rates compared to gas mixtures of O2 and HMDSO. Empirically obtained deposition models for the used symmetrical plasma reactor are given. Investigations on the three-dimensional (3D) uniformity of quartz-like coatings on polycarbonate blocks with and without recesses were performed. The deposition rate depends on the dimensions of the 3D-formed parts when depositing in front of the RF electrode. A higher pressure and use of power modulation can improve the coating uniformity in fissures.