COMPLETELY BISUBSTITUTED IRON-GARNET (BIG) FILMS PREPARED BY ELECTRON-CYCLOTRON RESONANCE (ECR) SPUTTERING

Completely Bi-substituted iron garnet (BIG) films were epitaxially synthesized on garnet substrates by electron cyclotron resonance (ECR) sputtering. The critical temperature for the epitaxial growth, crystallinities, and Faraday rotation theta(F) of BIG films depend on the O2 gas flow rate. With an optimum flow rate of 7 sccm, single-crystal BIG films were obtained at temperatures above 390-degrees-C, and theta(F) achieved its largest value of 8.4 x 10(4) deg/cm (lambda = 0.633-mu-m). The minimum ferromagnetic resonance (FMR) linewidth DELTA-H was 70 Oe; this is the smallest value ever reported. The uniaxial perpendicular magnetic anisotropy is mainly caused by the elastic deformation induced by the thermal expansion mismatch between the film and the substrate.