Analysis of Magnetic Properties of Magnetostrictive FeCoGa Thin Film Patterns Grown on Flexible Substrates

Magnetostrictive thin films deposited on flexible substrates have garnered significant attention due to their diverse applications in flexible magnetoelectronic devices, including flexible magnetic memory devices, sensors, and high-frequency devices. In this work, magnetostrictive FeCoGa thin films were deposited on polyimide (PI), polyester (PET), and mica flexible substrates. The rectangular and dumbbell-shaped thin film patterns with varying sizes were designed and implemented using microelectromechanical systems (MEMS) technology. The films were characterized using scanning electron microscopy (SEM), x-ray diffraction (XRD), vibrating sample magnetometry (VSM), and impedance analyzer. The results showed that magnetostrictive amorphous FeCoGa films were effectively formed on these flexible substrates. The patterns on the PI substrate exhibited low coercivity and the highest quality factor, while the patterns on the mica substrate demonstrated the lowest residual magnetism. The dumbbell-shaped patterns exhibited higher magnetic response sensitivity than the rectangular film patterns. Notably, the variation in resonance frequency between the array patterns was extremely small, at less than 0.18%, indicating excellent reproducibility and consistency of the magnetic properties of the patterns. The results confirmed the superior performance of dumbbell-shaped FeCoGa magnetostrictive film patterns on flexible substrates, providing valuable insights for the design of flexible magnetostrictive sensors.