Patent ID: 7510787

Claim:
A magneto-resistance effect element, in which a sensing current flows perpendicularly to a layer surface, comprising: a pinned layer having a fixed magnetization direction; a free layer having a magnetization direction variable depending on an external magnetic field; a nonmagnetic spacer layer disposed between said pinned layer and said free layer; at least one of said pinned layer and said free layer including a Heusler alloy layer which is disposed adjacent to said spacer layer and which virtually has a stoichiometric composition; an oxide distributed as a discontinuous film between at least one of the Heusler alloy layers and said spacer layer; and a Heusler base layer disposed between said oxide distributed as the discontinuous film and said Heusler alloy layer, said Heusler alloy layer being made of a Heusler alloy expressed by a composition formula X 2 YZ or XYZ (where X represents one or more elements selected from Co, Ir, Rh, Pt, and Cu, Y represents one or more elements selected from V, Cr, Mn, and Fe, and Z represents one or more elements selected from Al, Si, Ga, Sb, and Ge), and said Heusler base layer being made of CoXY, Co being 70 at % or greater and less than 100 at %, X representing at least one of Fe, Mn, and Cr, and Y represent at least one of Si, Ge, Al, and Sb.