Patent ID: 7695776

Claim:
A process for depositing a continuous, abrasion, chemical and impact resistant silicon oxynitride coating on a substrate comprising: admixing silane (SiH 4 ), one inert diluent gas selected from the group consisting of nitrogen gas (N 2 ), helium (He) and argon (Ar) and nitrous oxide (N 2 O) to provide a gas mixture; providing a plasma chamber suitable for plasma-enhanced chemical vapor deposition which contains a substrate and a substrate support electrode; introducing said gas mixture into said plasma chamber at a plasma source at flow rates of 85 slm/4.5 slm/30 sccm (SiH 4 /Diluent Gas/N 2 O) and applying RF power of 350 watts, equivalent to approximately 1.5 W/cm 2 , and a pressure therein of about 5 Torr, to generate a plasma from said gas mixture, said substrate being subjected to an electrode spacing of 300 mils from said plasma source, having a temperature between 300° and 360° C. and a deposition rate per minute of between about 4000 Å and 5000 Å during said process; wherein an optically transparent silicon oxynitride film of between about 10 and 5000 nm is formed on said substrate, said silicon oxynitride film having a refractive index of about 1.75, an atomic hydrogen content of less than 10% and a thickness uniformity on said substrate of about 5%.