MAGNETIC-PROPERTIES OF FESI-SIO2 GRANULAR FILMS

The ferromagnetic resonance (FMR) spectra and coercivities of FeSi-SiO 2 granular films have been measured over a wide range of FeSi volume fractions (fv). The films were prepared using the ion-beam sputtering technique and transmission electron microscopy showed that the FeSi alloy granules are embedded in a matrix of SiO2. An enhanced coercivity (Hc), as high as 329 Oe at room temperature, is observed. For some samples, there are several resonance peaks in the FMR spectra, which include one major peak and several minor peaks. The major and minor peaks correspond to the usual uniform mode and spin-wave respectively. In our experiments, the field separations between the major and the minor peaks show a complex fashion. Our results are discussed in comparison with some theoretical models.