Correlations of magnetic microstructure and anisotropy with noise spectra for CoNi and CoCrTa thin film media

The authors report on two thin-film-media alloys, Co/sub 86/Cr/sub 12/Ta/sub 2/ and Co/sub 75/Ni/sub 25/, which have very different noise characteristics. The magnetic microstructure of these films was observed with SEMPA (scanning electron microscopy with polarization analysis). Anisotropy and rotational hysteresis loss measurements have been made using a torque magnetometer. The distribution of anisotropy field H/sub k/ and its width dH/sub k/ have also been measured along with its different normalized values. It is suggested that the observed magnetic microstructure can be directly correlated with measured readback noise and anisotropy differences.<
>