Annealing effects on grain size, surface roughness, nanoindentation, and magnetic properties of Fe80Ce20 films deposited on PET and PMMA substrates

Rare earths (RE) and transition metals (TM) are widely studied for enhancing soft magnetic characteristics in magnetic devices. This study explores Fe80Ce20 films deposited on polyethylene terephthalate (PET) and polymethyl methacrylate (PMMA) substrates using direct current (DC) magnetron sputtering, focusing on the impact of film thickness and annealing temperature on structural, surface, magnetic, and mechanical properties. X-ray diffraction (XRD) confirmed the crystalline microstructure of Fe80Ce20 films, with body-centered cubic (BCC) α-Fe(110) phases. Atomic force microscopy (AFM) showed increased surface roughness with annealed grain size growth. The films were hydrophilic, and annealing increased the contact angle due to rougher surfaces. Surface energy was unaffected by film thickness. Optical properties indicated that thickness affects transmittance, with rougher surfaces causing light scattering. The films were too thin for significant substrate effects, and annealing did not eliminate residual stress. Hysteresis loops revealed good soft magnetic properties with a coercivity (Hc) of about 37Oe and saturation magnetization (Ms) over 1500 emu/cm3. Magnetic domain images showed a striped pattern, with changes in domain size affecting saturation magnetization.