US Patent 10090459 Magnetoresistive element

A magnetoresistive element includes a storage layer as a ferromagnetic layer which has magnetic anisotropy perpendicular to film planes, and in which a magnetization direction is variable, a reference layer as a ferromagnetic layer which has magnetic anisotropy perpendicular to film planes, and in which a magnetization direction is invariable, a tunnel barrier layer as a nonmagnetic layer formed between the storage layer and the reference layer, and a first underlayer formed on a side of the storage layer, which is opposite to a side facing the tunnel barrier layer, and containing amorphous W.