Patent ID: 7542249

Claim:
A bottom spin valve (BSV) giant magnetoresistive (GMR) sensor of the spin filter spin-valve (SFSV) type having high-conductance layers, a synthetic antiferromagnetic (SyAF) pinned layer and a composite ultra-thin ferromagnetic free layer comprising: a substrate; a bottom spin valve stack formed on said substrate and the formation further comprising: a buffer layer; an antiferromagnetic pinning layer formed on said buffer layer; a synthetic antiferromagnetic (SyAF) pinned layer formed on said pinning layer; a non-magnetic spacer layer formed on said SyAF pinned layer; an oxygen surfactant layer formed on a surface of said spacer layer distal to said SyAF pinned layer; a composite free layer formed on said oxygen surfactant layer, said composite free layer comprising: a first layer of CoFe having a thickness between approximately 15 and 18 angstroms formed on said surfactant layer; a first high-conductance layer of Cu having a thickness between approximately 2 and 3 angstroms formed on said first layer of CoFe; a second layer of CoFe having a thickness between approximately 2 and 5 angstroms formed on said first high-conductance layer of Cu; a second high-conductance layer (HCL) formed on said free layer; a capping layer formed on said second HCL; and said pinned layer being magnetized in a direction transverse to an air bearing surface plane of said sensor.