Fabrication and characteristics of SiOx films by plasma chemical vapor deposition of tetramethylorthosilicate

Silicon oxide films with a low content of carbon residue were deposited by plasma-enhanced chemical vapor deposition with tetramethylorthosilicate (TM OS) as the precursor. With this technique, hard, highly transparent and adh erent films can be successfully deposited on glass or poly(methyl-methacryl ate) (PMMA) substrates. Influences of plasma parameters such as plasma powe r, pressure of monomer and Ar plasma post-treatment on the film properties were investigated. Results have shown that the deposition rate of the tetra methylorthosilicate (TMOS) plasma films increased with increasing r.f. powe r. FTIR spectra of SiOx films deposited from TMOS are very similar to those of pure SiO2. Most of the -CHn groups (at 285.4 eV) of TMOS films disappea red and converted to -C-CO (at 288.6 eV) as observed in the C Is spectra af ter Ar plasma treatment. Surface hardness of the films deposited on glass a nd PMMA substrates is improved to 8H and 4H, respectively. After Ar plasma treatment, the hardness of films deposited on PMMA can be further increased to 6H. The TMOS films also have a high transmission of 90% in the waveleng th range from 400 to 800 nm. (C) 2000 Elsevier Science S.A. All rights rese rved.