Stress-controllable microwave ferromagnetic performances of amorphous Fe56Co24B20 films prepared by pulsed laser deposition

A stress deposition was proposed in pulse laser deposition (PLD) device with a tunable substrate curvature fixture. Various Fe56Co24B20 amorphous thin films with different compressive stresses were prepared using the home-made stress-PLD device. It is interesting to note that the compressive stress, resulted from vaulted substrates, leads to a well-defined in-plane uniaxial magnetic anisotropy. As a result, tunable self-bias microwave ferromagnetic performances are achieved. With the increase of stress (i.e. substrate curvature), the magnetic anisotropy field HK increases from 2.1 to 14.2 kA/m and the ferromagnetic resonance (FMR) frequency fr up to 4.03 GHz was obtained. This stress-deposition method not only tailors the FMR frequency of magnetic films, but also reduces their magnetic loss.