Recording performance of thin film media with various crystallographic preferred orientations on glass substrates

CoPtCrTa films, with CrTi underlayer and a variety of crystallographic preferred orientations, were prepared on glass substrates. AlN, NiAl or Ta seed layers, deposited prior to deposition of the underlayer, were used to control the crystal orientation and grain size of the underlayer and thereby the magnetic layer. The correlation of magnetic and structural properties was studied. The media noise was found to depend primarily on grain size and grain size dispersion; the crystal orientation of the film had a secondary role. For a given CrTi underlayer, the [1010] preferred orientation was associated with the highest coercivity.