G. L. Doll, Timken Technology Center, Canton, OH
Chemical Vapor Deposition (CVD) of films and coatings involves the chemical reaction of gases on or near a substrate surface. This deposition method can produce coatings with tightly controlled dimensions and novel structures. Furthermore, the non-line-of-sight-deposition capability of CVD facilitates the coating of complex shaped mechanical components. Conventional CVD utilizes substrate temperature to drive the chemical reaction of the gas species. Thermal compatibility between the substrate and the reactants can impose limitations on the scope of coating and substrate materials. Incorporation of plasma excitation to fully or partially drive chemical reactions reduces these material limitations in many cases. CVD thin films and coatings are used in many applications and can be formed from semiconductor, dielectric, ceramic, and metal materials. CVD is also suitable for fiber production and fiber coatings. This presentation provides an overview of CVD, discusses some of its fundamental and practical aspects, and examines its advantages and limitations versus other vapor processing techniques such as Physical Vapor Deposition in regard to coatings for mechanical applications.