  Nanocrystalline FeCuNbSiB thin films were fabricated through magnetron
sputtering followed by heat treatment, resulting in samples characterized by
low coercivity and high effective magnetization. Comprehensive microstructural
analysis, employing X-ray diffraction and transmission electron microscopy
techniques such as selected area electron diffraction, high-resolution imaging,
and Fourier transform, was conducted. Magnetic properties were investigated
using an alternating gradient field magnetometer and broadband ferromagnetic
resonance. The structural analysis revealed a well-defined microstructure of
nanograins within an amorphous matrix in all of our films. However, the
coercivity of the 80 nm films did not exhibit as low values as observed for the
160 nm films
