Improvement of Performance in Continuously Vacuum Deposited Co-Cr Film by Substrate Treatment

Dependence of the perpendicular anisotropy of continuously vacuum deposited Co-Cr films on glow discharge treatment of the polymer base film surface, and on the thickness of a Ti underlayer, was investigated. The relation between the film microstructure and the recording characteristics of the Co-Cr film media was also studied. When the polymer film surface was pretreated by glow discharge with Ar gas, the Hkeff of the Co-Cr films decreased, but when H2 gas was used instead of argon, the deterioration of the Hkeff was negligible. Co-Cr films deposited on a Ti underlayer had a high Hkeff regardless of the glow discharge treatment conditions. The Ti underlayers had to be more than 40 Å thick in order for the Co-Cr films to have a small ¿¿50, around 5 or 6°. The Co-Cr films showed a columnar structure when the Ti underlayer thickness was in the range from 100 to 2000 Å Co-Cr films with a columnar structure yielded a high reproduced voltage.