Patent ID: 7087324

Claim:
A magnetoresistive spin-valve sensor comprising: a magnetic layer, the magnetic layer forming a free layer and having an effective magnetic layer thickness, excluding a thickness of a magnetically dead layer, greater than 0 and less than approximately 40 Å; another magnetic layer which forms a pinned layer; a spacer layer interposed between the two magnetic layers; an antiferromagnetic layer adjacent to the pinned layer, opposite to the spacer layer; a specular layer made of a metal oxide; a back layer, made of an AuCu or AgCu alloy, interposed between the magnetic layer and the specular layer, wherein said AuCu alloy has an atomic content of Au between 9.2 and an 15.9 at % and said AgCu alloy has an atomic content of Ag between 11.0 and 28.3 at %, and a metal layer having a thickness of 10 to 50 Angstroms disposed adjacent to the specular layer, opposite to the back layer, and made of a metal which improves GMR performance of the magnetoresistive spin-valve sensor, wherein the metal layer is made of a material selected from a group of Ta, Ru, Ni, Fe, Pd, Pt, Mn, Cu, Co, Ti, V, Cr, Zn, Y, Zr, Nb, Mo, Rh, Ag, Au, Hf, W, Re, Os, Ir, Nb and alloys thereof.