Double synthetic antiferromagnet using rare earth metals and transition metals

摘要

A mechanism relates to magnetic random access memory (MRAM). A free magnetic layer is provided and first fixed layers are disposed above the free magnetic layer. Second fixed layers are disposed below the free magnetic layer. The first fixed layers and the second fixed layers both comprise a rare earth element.

主权项

1. A method of forming a magnetic random access memory (MRAM) device, comprising:
forming a first dipole magnetic layer in direct contact with a second dipole magnetic layer, wherein the first and second dipole magnetic layers have opposite pointing magnetic moments, the first and second dipole magnetic layers together forming a first synthetic antiferromagnet, wherein the first and second dipole magnetic layers comprise alternating layers of a rare-earth metal and a transition-metal multilayer, wherein the rare-earth metal is selected from a group consisting of Tb and Gd, wherein the first and second dipole magnetic layers together forming the first synthetic antiferromagnet have a first coercivity; forming an oxide seed layer in direct contact with the first dipole magnetic layer; forming a free magnetic layer in direct contact with the oxide seed layer; forming a tunnel barrier in direct contact with the free magnetic layer; forming a first reference magnetic layer in direct contact with the tunnel barrier; forming a nonmagnetic spacer layer in direct contact with the first reference magnetic layer; and forming a second reference magnetic layer in direct contact with the nonmagnetic spacer layer, wherein the first and second reference magnetic layers have opposite pointing magnetic moments, the first and second reference magnetic layers together forming a second synthetic antiferromagnet, wherein the first and second reference magnetic layers are made of a same material as the first and second dipole magnetic layers, wherein the first and second reference magnetic layers together forming the second synthetic antiferromagnet have a second coercivity, wherein the first coercivity is greater than the second coercivity, wherein the first dipole magnetic layer and the first reference magnetic layer have a same thickness ranging from 1-10 nanometers, wherein the second dipole magnetic layer and the second reference magnetic layer have a same another thickness ranging from 1-10 nanometers, wherein when a magnitude of a dipole field for the first reference magnetic layer increases because of a change in temperature a magnitude of a dipole field for the first dipole magnetic layer increases in a same amount.