Formation of Fe–Co/glass multilayer films via pulsed laser deposition

Sputtering-made magnetic thin films with metal–ceramic multilayer structures have been reported to achieve excellent magnetic properties and/or new functions for various magnetic materials. However, sputtering-made magnetic films tend to have 10 or fewer layers because the main applications of thin films, such as magnetic sensors, recording heads and recording media, require thin films thinner than 1 μm. This paper reports an Fe–Co/glass multilayer thick-film that has an approximate thickness of 10 μm (above 100 layers). This thick-film was prepared via pulsed laser deposition using several composite targets (two- or three-layer targets) consisting of an Fe–Co alloy (or Fe–Co sheet) and a glass plate. The fabrication of an Fe–Co single-layer film and a glass single-layer film was examined to determine the optimal defocus rate for the composite target. Then, we confirmed that the use of a [glass plate]/[Fe–Co alloy] two-layer target enabled the local formation of a [20 nm thick Fe–Co]/[10 nm thick glass) laminated structure with approximately 130 layers. An Fe–Co/glass multilayer structure was formed by using a three-layer target of a [Fe–Co sheet]/[glass plate]/[metal alloy]. Nonetheless, the results also suggest that large glass droplets should be removed in future work to create homogeneous multilayer thick-films.