Abstract
It is well known that the magnetic properties of Co-Cr film vary with several sputtering parameters, among which impurities of sputtering gas and target are very important. However, the effect of impurities in the target has not previously been investigated. In this paper, we describe the effect of oxygen content in sputtering targets on the magnetic properties of Co-Cr film. In a range of a small amount of oxygen, with increasing oxygen content Hk and Hc(⊥) of Corich magnetic particles was thought to be enhanced. However, with further increase of oxygen content, the crystal orientation was so markedly degraded that the Hk and Hc(⊥) showed too small values for a perpendicular medium. This effect is more severe for thinner Co-Cr film below 0.1μm. Finally, it is concluded that the impurity oxygen content of the target should be as small as possible to realize excellent properties of the Co-Cr medium in a mass production system.
