Chemical cleaning treatment of textured nickel for the deposition of epitaxial thin films

Coated conductors employing rolling-assisted-biaxially-textured-substrates offer a viable alternative to the BSCCO power-in-tube tapes. These conducto rs are based on the deposition of biaxially oriented buffer layers and YBCO films on textured nickel alloy substrates. Researchers are becoming increa singly aware that the cleanliness of the nickel surface plays a crucial rol e in making it conducive to epitaxial film deposition. Several cleaning tec hniques are currently being explored. In this work we report the results ob tained from a simple chemical cleaning procedure based on an aqueous soluti on of formic acid and hydrogen peroxide. X-ray photoelectron spectroscopy s tudies were performed to understand the effect of the cleaning treatment on the nickel surface. It was found that the cleaning treatment significantly enhances the ability of the nickel to act as a crystallographic template f or the deposition of strontium titanate using a metallorganic decomposition process. These results give promise for the development of scalable cleani ng procedures for coated conductor applications.