Deposition of silicon oxycarbide thin films from an organosilicon source for polycarbonate glazing

To enhance the abrasion resistance of polycarbonate used to replace glass, a silicon oxycarbide thin film was deposited at < 100 °C using a slot antenna electron cyclotron resonance plasma enhanced chemical vapor deposition system and an organosilicon source. The thin film deposition rate, which varied as a function of microwave power and whether Ar or O₂ was used to form the plasma, was above 500 nm/min even at 2 Pa, and reached 1 μm/min as the microwave power increased. The transmittance of visible light was over 90% after thin film deposition, indicating performance similar to that of glass. The Taber abrasion test showed that the Δhazes of the thin films were under 5%, which indicates better performance than the siloxane-based wet coating sample (Momentive, AS4700) and the commercial hard plasma coating product LEXAN MR-10. Furthermore, the thin film deposited at 1.7 kW exhibited similar abrasion resistance to that of glass. In addition, adhesion improved significantly when consecutive, minute-long 1.7 kW Ar and O₂ plasma surface treatments were performed before the depositions. - Highlights: • Silicon oxycarbide was microwave plasma-deposited for polycarbonate (PC) glazing. • Abrasion resistance was better than those of wet coating and a plasma-coat product. • ΔHaze values below 2% indicated the same abrasion resistance as glass. • Consecutive Ar and O₂ plasma treatments significantly improved adhesion. • This technology may help to replace glass with plastic for various applications.