A magnetic detection device and a manufacturing method for the same that
allows effective control of the magnetization of a free magnetic layer in
a design with narrower tracks. A second antiferromagnetic layer is
deposited on a free magnetic layer, and a thin nonmagnetic layer formed
from an element such as Ru or the like is deposited on the second
antiferromagnetic layer. Third antiferromagnetic layers are deposited on
both end portions of the free magnetic layer. Both end portions of the
second antiferromagnetic layer exhibit antiferromagnetic properties so
that the magnetization of both end portions of the free magnetic layer is
firmly fixed. A central portion of the second antiferromagnetic layer is
non-antiferromagnetic. A central portion of the free magnetic layer is
formed into a weak single domain so it permits inverted magnetization in
response to an external magnetic field.
