MAGNETORESISTIVE DEVICE AND ITS PRODUCING METHOD

摘要

The present invention provides a magnetoresistive element that has excellent magnetoresistance characteristics over a conventional magnetoresistive element. The magnetoresistive element is produced by a method including heat treatment at 330 DEG C or more and characterized in that the longest distance from a centerline (10) of a non-magnetic layer (4) to the interfaces between a pair of ferromagnetic layers (3, 5) and the non-magnetic layer (4) is not more than 10 nm. This element can be produced, e.g., by forming an underlying film on a substrate (1), heat-treating the underlying film at 400 DEG C or more, decreasing surface roughness by irradiating the surface of the underlying film with an ion beam, and forming the ferromagnetic layers (3, 5) and the non-magnetic layer (4). The longest distance is reduced relatively even when M<1> (at least one element selected from Tc, Re, Ru, Os, Rh, Ir, Pd, Pt, Cu, Ag and Au) is present in the ferromagnetic layers (3, 5) in the range of 2 nm from the interfaces with the non-magnetic layer (4).