ABSTRACT
In chemical vapour deposition (CVD) a solid is deposited from a chemically reactive vapour onto a solid surface or ‘substrate’. The ‘age of materials’ is the response to problems, recognising that the development of new materials provides the means to overcome many of the present limitations. CVD is one of the key techniques in the development of new manufacturing processes. New processes to form diamond coatings at moderate pressures and temperatures are also based on the use of CVD. The greatest limitation to the industrial exploitation of CVD is the low rate at which deposition takes place. Frost formation is a sort of CVD process; gas phase water molecules diffuse to a surface and are deposited and frozen there. Chemical engineering concepts have been central to the development of CVD techniques. One or more chemical reactions are at the heart of a CVD process and a knowledge of the chemistry is important.
