Process and device for coating the inner surface of greatly arched, essentially dome-shaped substrate by CVD

US5496586A · kind A · utility

Assignee

• Schott Glaswerke · DE

Inventors

• Ewald Mo/ rsen · Mörfelden, DE
• Helge Vogt · Nackenheim, DE
• Johannes Segner · Stromberg, DE

Key dates

• Filing date: Oct 26, 1993
• Grant date: Mar 5, 1996
• Expiry date: Oct 26, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C23C16/045
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

A process for coating the inner surface of a greatly arched, essentially dome-shaped substrate by CVD is described wherein reaction gases, which contain layer-former molecules, are conveyed into a reaction chamber containing the substrate(s) to be coated. The reaction gases are conveyed through at least one gas inlet, placed facing the vertex of the dome at a distance from the surface to be coated. Deposition of the layer material on the substrate is brought about by producing a reaction zone on the inner surface of the substrate to be coated. The reaction gases do not, as is usual for known processes, flow slowly into the reaction chamber. Instead, for production of a uniform coating, the reaction gases are introduced at a high speed such that the product of Reynolds number, R, of the gas jet in or in the immediate vicinity of the gas inlet and the distance, h, between the gas inlet and the dome vertex is 400<R.times.h[mm]<4000.