Atmospheric-pressure plasmas for wide-area thin-film deposition and etching

The present paper is focused on coating technologies compatible with industrial requirements, particularly on atmospheric pressure plasma technologies which are compatible with scaling to wide substrate widths (greater-than, equal or similar 0.5 m). The AP-PECVD reactors are designed for continuous air-to-air processing, and can be used for deposition of non-oxide films. Two thermal methods for atmospheric pressure processing are considered: microwave CVD and DC ArcJet-CVD. Typical thin film growth rates for PECVD are in the range of 5-100 nm•s(sup -1) (static) and up to 2 nm•m•s(sup -1) (dynamic). The rates for plasma chemical etching are typically 10 times higher. A complimentary lower energy plasma source based on dielectric barrier glow discharge plasma CVD has also been explored. Developments are underway to explore uses for the coating technology, for example scratch resistant coatings on metals, barrier layers, self-clean functional surfaces and antireflective coatings. Coating materials range from silica, titania, aluminium oxide, metal composite layers, carbon and silicon nitride. Layer properties are close to data known from low pressure PECVD. Plasma chemical etching has been developed for crystalline silicon photo-voltaics. The surface textures strongly change with the precursors and the plasma parameters used