Pt/Ti composite underlayers and Pt interlayers for Co-Cr-Ta Perpendicular Magnetic Recording Media

Abstract

Pt/Ti composite underlayer has been investigated for Co-Cr-Ta perpendicular magnetic recording media. The Co-Cr-Ta/Pt/Ti trilayered films exhibited more excellent c-axis orientation and higher perpendicular coercivity than Co-Cr-Ta/Pt and Co-Cr-Ta/Ti bilayered films. In order to decrease grain size in Co-Cr-Ta films, 5 nm-thick Pt interlayer was introduced to compose [Co-Cr-Ta/Pt]_n multilayers. It was found that the Pt interlayer was effective to obtain small Co-Cr-Ta particles without decrease of perpendicular coercivity.