Until recently, CVD technology was effectively available only to large international glass companies who had developed the technology in-house. However, for the first time it has now become possible for any glass company to purchase CVD. A variety of techniques are available to deposit thin films on flat glass. The most widely used for producing high quality functional coatings can be subdivided into two classes: physical vapour deposition (PVD) & chemical vapour deposition (CVD). PVD processes include a number of approaches-sputtering is the one most widely used for glass. Sputtered coatings are generally referred to as soft coated. Pyrolytic coatings are applied using CVD methods & are often referred to as hard coated. Both types of coating offer their own advantages & disadvantages.
