A seed layer is formed containing Cr and an element X (wherein the element
X is Fe, Ni, etc.) on a substrate layer formed from Ta, etc. At this time,
the compositional ratio of the aforementioned Cr is specified to be 80 at
% or more, and the seed layer is formed to have a film thickness of 20
.ANG. or more, but 130 .ANG. or less. According to this, the wettability
of the seed layer surface can be improved remarkably compared to that
heretofore attained, the unidirectional exchange bias magnetic field and
rate of resistance change in the fixed magnetic layer can be increased,
and it becomes possible to make the smoothness of the surface of each
layer on the aforementioned seed layer excellent.
