Investigation of Sm Addition on Microstructural and Optical Properties of CoFe Thin Films

CoFe-based alloys and rare earth (RE) elements are among the most studied materials in applying magnetic devices to improve soft magnetic characteristics. A series of Co₄₀Fe₄₀Sm₂₀ films are deposited on a glass substrate via the sputtering technique, followed by an annealing process to investigate their effect on microstructural and optical properties of Co₄₀Fe₄₀Sm₂₀ films. In this study, the increase in the thickness of Co₄₀Fe₄₀Sm₂₀ films and annealing temperatures resulted in a smoother surface morphology. The 40 nm Co₄₀Fe₄₀Sm₂₀ films annealed 300 °C are expected to have good wear resistance and adhesive properties due to their high values of H/E ratio and surface energy. Optical transparency also increased due to the smoother surface of the Co₄₀Fe₄₀Sm₂₀ films.