Magnetic and structural characterization and ferromagnetic resonance study of thin film HITPERM soft magnetic materials for data storage applications.

HITPERM/SiO[SUB2] single and multilayer thin films have been produced using a target composition of Fe[SUB]70Co[SUB30])[SUB88]Zr[SUB7]B[SUB4]Cu[SUB1]. The as-deposited HITPERM film contains small bcc (or B2) nanocrystals of volume fraction less than 10% surrounded by an amorphous matrix. The lattice parameter of the nanocrystal is about 5% larger than an equilibrium FeCo phase. The saturation induction determined from FMR measurements (1.53±0.08 T) is consistent with VSM and SQUID measurements (1.45-1.5 T) and also with as-spun amorphous ribbons (1.55-1.62 T). The Landé g-factors (2.15±0.05) are typical of transition metals, particularly, of Fe. The Landau-Lifshitz-Gilbert damping parameters of the single and multilayered films are small (α=5 0.005±60.0004) with each layer acting almost independently. Neither thickness variation of each layer nor the number of stacking significantly affects the damping process in a range of film thicknesses of 50-150 nm, while the coercivities are strongly dependent on those parameters. This supports a notion that the damping parameter is an intrinsic property. [ABSTRACT FROM AUTHOR]