PERPENDICULAR MAGNETIC RECORDING MEDIUM

摘要

PURPOSE:To permit recording with large reproduction output and at a high density by decreasing the concn. of an alloy element added to Co in the direction nearer the surface of a film from a substrate. CONSTITUTION:The concn. of the additive alloy element is decreased from the substrate toward the surface of a medium at the time of forming a perpendicularly magnetized film consisting of a Co-base alloy on the substrate. More specifically, the crystal grains having good C-axis orientational property are formed in the initial period of the film formation and the growth of the crystal grains constituting the film progresses epitaxially and continuously in succession even if the amt. of the additive element to be added is decreased. The perpendicularly magnetized film which has the excellent C-axis orientational property over the entire part of the film and has the large saturation magnetization by a decrease in the content of the additive element in the upper part in the film is, therefore obtd. The increased reproduction output and improved recording density at the time of recording and reproducing by a magnetic head are thus obtd.