Application of co-sputtering method with multiple targets for amorphous thin films of nickel

A process and equipment for multiple-target co-sputtered thin film formation are developed. The report outlines the process and its application to the formation of amorphous Ni-Si-B thin film. It also discusses some important surface and interface phenomena that may have major effects in practical film formation by the process. The equipment is useful not only for performing multiple-target co-sputtering successfully without a significant decrease in film formation rate but also for synthesizing chemical compounds in layers (epitaxial sputtering). Film produced by multiple-target co-sputtering has smooth, uniform surface. Microscopic structures in such film are found to have large effects on the characteristics and durability of Ni-Si-B film. These and other observations demonstrate the usefulness of the multiple-target co-sputtering process. A study is also made on the reaction taking place at the surface between Ni-Si-B film and solder. Results indicate that dispersion of Sn into the film can be prevented by inserting an iron layer between the film and solder layer. (N.K.)