2004 年 28 巻 3 号 p. 289-294
We propose a noble stacked soft magnetic underlayer (SUL) with the so-called top-type pinning structure, which consists of a soft magnetic layer (SM layer) fabricated by plating and an antiferromagnetic layer (AFM layer) deposited by sputtering, on an Al/NiP disk. Through investigation of the structure and magnetic properties of this stacked SUL, we clarified the following points: (1) the thermal stability of NiFeP plated on an Al/NiP disk is 280°C, which is the crystallization temperature of the amorphous NiP layer; (2) to induce large unidirectial magnetic anisotropy in the SUL, it is necessary to introduce a soft magnetic buffer layer and apply dry etching to the NiFeP surface; (3) a unidirectional magnetic anisotropy field can be induced in an SM layer fabricated by plating as well as in one fabricated by sputtering, which results in the whole disk having a single-domain structure.