GB990692A - Foil production - Google Patents

Abstract

A method of continuously producing foil comprises vapour depositing a material such as Ti, Ta, W, Cu, Al, a metal oxide or a dielectric on to a moving substrate and then peeling off the deposit in the vacuum chamber and removing the foil from the chamber by passing it through differential vacuum stages. The substrate may be treated with a wetting agent or oil prior to the deposition of the foil material in order to limit the adhesion of the foil material. In some cases e.g. stainless steel as the substrate this treatment is not necessary. Glass may also be used as a substrate and multi layers may be deposited to form laminated foils e.g. Cu on stainless steel followed by a dielectric material on the copper. In the formation <PICT:0990692/C6-C7/1> of metal oxide foil a supply of oxygen is allowed into the vacuum furnace to avoid dissociation of the oxide. The foil thickness is generally between 0.002 inch and 0.005 inch but may be <0.001 inch. Apparatus for producing the foil comprises a vacuum chamber 51, a vapour source 61 heated by resistance, induction or electron beam bombardment, a substrate 63 in the form of an endless belt which moves above source 61 at a controlled rate, a source of wetting agent 73, a stripping device 67 to peel the foil off the substrate and a coiler 71 for the finished foil. The material to be evaporated may be fed continuously to the source 61 from a coil 62.