COATINGS FOR THE APS RF CAVITY TUNERS FOR THE REDUCTION OF SECONDARY ELECTRONS *

Thin film coatings are used to reduce the generation of secondary electrons at the ends of the Advanced Photon Source (APS) rf cavity tuners because these electrons result in increased temperatures on the tuner. To improve the film properties over the existing evaporated titanium film, a magnetron-sputtered film of titanium nitride has been developed that is both harder and adheres more strongly than the past evaporated film. This paper describes the process for creating this new coating.