Effects of Improved Background Pressure on the Deposition of Co-Cr Perpendicular Anisotropy Films

Abstract

The effects of improved background pressure on the deposition of Co-Cr perpendicular anisotropy films were investigated. To obtain a high vacuum, an aluminum alloy chamber was used, whose inside wall was subjected to the EL process ro reduce outgassing from the chamber. The background pressure reached 4×10-8 Torr after chamber baking. The pressure was changed by the addition of nitrogen to the atmosphere. In spite of the nitrogen addition, the percentage of H2O in the atmosphere was greater than that of N2. As a result, we were able to obtain a high perpendicular coercive force and a high crystallinity for the deposition of Co-Cr at a low background pressure. As regards the recording performance, a perpendicular double-layered medium with the Co-Cr recording layer deposited in a high vacuum showed larger output than one deposited in a low vacuum.