To enable a ferromagnetic tunnel junction magnetoresistance effect element to realize a stable and high magnetoresistance effect, by a method wherein the tunnel effect of an insulator layer junction part consisting of a first ferromagnetic layer, an insulator layer which is formed by sputtering an alumina film and is formed in a specified thickness, and a second ferromagnetic layer, is utilized.
A first ferromagnetic CoFe layer 2, an insulator layer 3 and a second ferromagnetic NiFe layer 4 are formed in the order of the layer 2, the layer 3 and the layer 4 on a glass substrate 1 using a metal mask to manufacture a cross-shaped tunneling element. Any layer of the layers 2 and 4 is formed in a width of 0.3 mm, for example, and a thickness of 20 nm, for example, and the layer 3 is formed by sputtering an alumina film as a target. It is preferable that the thickness of the layer 3 is a thickness of 1 nm or thicker, and, if the layer 3 is formed in a thickness exceeding 2 nm, the value of insulation resistance of a ferromagnetic tunnel junction magnetoresistance effect element becomes too higher and it becomes difficult to use the material as an element. Therefore, it is preferable to limit the thickness of the layer 3 to a thickness confined to 2 nm and preferably the thickness of the layer 3 is a thickness of 1.4 to 2 nm.
YAMAZAKI ATSUSHI
MORIGUCHI KOJI
TANOGAMI SHUJI
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