Patent ID: 7079361

Claim:
A magnetoresistive memory device, comprising: a multi-layer film comprising at least two magnetic layers and at least one non-magnetic layer made of an insulating material interposed between the two magnetic layers, wherein a resistance value changes with a relative angle formed by magnetization directions of the at least two magnetic layers, and at least one of the magnetic layers is a laminated layer including a first layer of the ferromagnetic material consisting of M 100-a X a , a metal layer, and a second layer of the ferromagnetic material consisting of M 100-a X a , which are stacked in this order, where M is at least one element selected from the group consisting of Fe, Co and Ni, X is one element selected from the group consisting of Pt, Pd and Ir, and a satisfies the following equation, 0.05≦a≦60, and wherein a ratio MR(T)/MR(280) is 0.8 or more, where the MR(T) is defined as the MR ratio after heat treatment at a temperature of T° C. and the MR(280) is defined as the MR ratio after heat treatment at 280° C.