Microstructural study of electroless-plated CoNiP ternary alloy films for perpendicular magnetic recording media

摘要

The microstructure of electroless CoNiP films with various H/sub c/( perpendicular to ) values for use as perpendicular magnetic recording media was investigated. It was observed that the H/sub c/( perpendicular to ) values of the films varied according to their microstructure. The film which showed the highest H/sub c/( perpendicular to ) value contained large columnar grains with high crystallinity, whereas such a clear columnar structure was not observed in the films with lower H/sub c/( perpendicular to ) values. The shape anisotropy due to the columnar structure effectively contributes to the magnetic properties of the films as well as magnetocrystalline anisotropy associated with preferred crystallographic orientation. The results of compositional analysis of ultra-small regions suggested that the formation of low M/sub s/ and low H/sub c/ regions at the initial deposition stage was due to a preferential deposition of Ni.