Method and system for providing a stable spin filter

A spin filter comprising:

• a pinned layer;
• a free layer;
• a nonmagnetic spacer layer residing between the pinned layer and the free layer, the nonmagnetic spacer layer being conductive;
• a spin filter layer adjacent to the free layer and on an opposite side of the free layer as the nonmagnetic spacer layer, the spin filter layer including Pt and/or Rh;
• a capping layer on the spin filter layer, the capping layer having a specular reflection layer therein, the specular reflection layer including at least one oxidized or nitrided material selected from a group consisting of Ta, Ti, Zr, Hf, Nb, Al, Mo, W, Si, Cr, V, Ni, Co, and Fe;
• wherein the capping layer further includes a metallic portion, the metallic portion residing between the spin filter layer and the specular reflection layer.

A method for providing a spin filter comprising:

• (a) providing a pinned layer;
• (b) providing a nonmagnetic spacer layer;
• (c) providing a free layer, the nonmagnetic spacer layer residing between the pinned layer and the free layer, the nonmagnetic spacer layer being conductive;
• (d) providing a spin filter layer adjacent to the free layer and on an opposite side of the free layer as the nonmagnetic spacer layer, the spin filter layer including at least one material selected from the group consisting of Pt and Rh;
• (e) providing a capping layer on the spin filter layer, the capping layer having a metallic layer and a specular reflection layer, the metallic layer residing between the spin filter layer and the specular reflection layer, the specular reflection layer configured to allow specular reflection of current carriers traveling from the spin filter layer to the specular reflection layer.

A method for providing a spin filter comprising:

• providing a pinned layer;
• providing a nonmagnetic spacer layer;
• providing a free layer, the nonmagnetic spacer layer residing between the pinned layer and the free layer, the nonmagnetic spacer layer being conductive;
• providing a spin filter layer adjacent to the free layer and on an opposite side of the free layer as the nonmagnetic spacer layer, the spin filter layer including at least one material selected from the group consisting of Pt and Rh;
• providing a capping layer on the spin filter layer, the capping layer having a specular reflection layer therein, the specular reflection layer including at least one oxidized or nitrided material selected from a group consisting of Ta, Ti, Zr, Hf, Nb, Al, Mo, W, Si, Cr, V, Ni, Co, and Fe;
• wherein the step of providing the capping layer further includes
• providing a metallic portion, the metallic portion residing between the spin filter layer and the specular reflection layer.

A spin filter comprising:

• a pinned layer;
• a free layer;
• a nonmagnetic spacer layer residing between the pinned layer and the free layer, the nonmagnetic spacer layer being conductive;
• a spin filter layer adjacent to the free layer and on an opposite side of the free layer as the nonmagnetic spacer layer, the spin filter layer including Pt and/or Rh;
• a capping layer on the spin filter layer, the capping layer having a specular reflection layer therein, the specular reflection layer including at least one oxidized or nitrided material selected from a group consisting of Ta, Ti, Zr, Hf, Nb, Al, Mo, W, Si, Cr, V, Ni, Co, and Fe;
• wherein the oxidized or nitrided material is selected from a group consisting of Zr, Hf, Nb, Mo, W, V, Ni, Co, and Fe.

A method for providing a spin filter comprising:

• providing a pinned layer;
• providing a nonmagnetic spacer layer;
• providing a free layer, the nonmagnetic spacer layer residing between the pinned layer and the free layer, the nonmagnetic spacer layer being conductive;
• providing a spin filter layer adjacent to the free layer and on an opposite side of the free layer as the nonmagnetic spacer layer, the spin filter layer including at least one material selected from the group consisting of Pt and Rh;
• providing a capping layer on the spin filter layer, the capping layer having a specular reflection layer therein, the specular reflection layer including at least one oxidized or nitrided material selected from a group consisting of Ta, Ti, Zr, Hf, Nb, Al, Mo, W, Si, Cr, V, Ni, Co, and Fe;
• wherein the oxidized or nitrided material is selected from a group consisting of Zr, Hf, Nb, Mo, W, V, Ni, Co, and Fe.