CPP magnetic sensing element in which pinned magnetic layers of upper and lower multilayer films are magnetized antiparallel to each other, method for making the same, and magnetic sensing device including the same

A magnetic sensing element comprising:

• a lower multilayer film and an upper multilayer film;
• each multilayer film comprising, a lower pinned magnetic layer, a lower nonmagnetic layer, a free magnetic layer, an upper nonmagnetic layer, and an upper pinned magnetic layer deposited in that order from the bottom,
• a lower antiferromagnetic layer disposed on the bottom of the lower multilayer film;
• an intermediate antiferromagnetic layer disposed between the lower multilayer film and the upper multilayer film;
• and
• an upper antiferromagnetic layer disposed on the top of the upper multilayer film,
• wherein the magnetization of each pinned magnetic layer is pinned in a predetermined direction by an exchange coupling magnetic field produced between the pinned magnetic layer and the adjacent antiferromagnetic layer;
• wherein a current flows perpendicular to the plane of each layer;
• and
• wherein the magnetization direction of the upper and lower pinned magnetic layers in the lower multilayer film and the magnetization direction of the upper and lower pinned magnetic layers in the upper multilayer film are antiparallel to each other.