Patent ID: 8319297

Claim:
A magnetic tunnel junction structure comprising a first magnetic layer having a fixed magnetization direction; a second magnetic layer having a reversible magnetization direction; a non-magnetic layer tunnel barrier formed between the first magnetic layer and the second magnetic layer; a third magnetic layer allowing the magnetization direction of the first magnetic layer to be aligned perpendicular with respect to a plane of the first magnetic layer by a magnetic coupling to the first magnetic layer, and having a perpendicular magnetic anisotropic energy thereof larger than an in-plane magnetic anisotropic energy thereof; a first crystal-structure separation layer formed between the first magnetic layer and the third magnetic layer for separating a crystallographic structure of the first magnetic layer from that of the third magnetic layer; a fourth magnetic layer allowing the magnetization direction of the second magnetic layer to be aligned perpendicular with respect to a plane of the second magnetic layer by a magnetic coupling to the second magnetic layer, and having a perpendicular magnetic anisotropic energy thereof larger than an in-plane magnetic anisotropic energy thereof; and a second crystal-structure separation layer formed between the second magnetic layer and the fourth magnetic layer for separating a crystallographic structure of the second magnetic layer from that of the fourth magnetic layer, wherein at least one of the first and second magnetic layers has a body centered cubic structure, and at least one of the third and fourth magnetic layers has a face centered cubic structure, a face centered tetragonal structure or a hexagonal close-packed structure, wherein each magnetization easy axis of the third and fourth magnetic layers is oriented perpendicular to each plane of the first and second magnetic layers.