A study on VMn underlayer in CoCrPt longitudinal media

Abstract

In this study, effects of a novel VMn underlayer on magnetic properties of a CoCrPt/VMn longitudinal medium were studied and compared with those of a CoCrPt/Cr medium. It was found that the VMn film had (200) preferred orientation and the lattice constant was about 0.2967 nm, which is slightly larger than that of the Cr, 0.2888 mn. The grain size of the VMn film was 9.8 mn at 30 nm thickness and this is about 39% smaller than that of a similarly deposited Cr film. The CoCrPt/VMn films showed higher coercivity in comparison with the CoCrPt/Cr films. V and Mn have diffused into the CoCrPt magnetic layer more uniformly rather than preferentially along grain boundaries and this reduced Ms at higher substrate temperature. However, due to the grain structure of the CoCrPt on the VMn underlayer, we have introduced a CrMo intermediate layer and its magnetic properties are described.