US 7,583,481 B2 · FCC-like trilayer AP2 structure for CPP GMR EM improvement

Abstract

A CPP-GMR spin valve having a pinned layer with an AP2/coupling/AP1 configuration is disclosed wherein the AP2 portion is a FCC-like trilayer having a composition represented by CoZFe(100-Z)/Fe(100-X)TaX/CoZFe(100-Z) or CoZFe(100-Z)/FeYCo(100-Y)/CoZFe(100-Z) where x is 3 to 30 atomic %, y is 40 to 100 atomic %, and z is 75 to 100 atomic %. Preferably, z is 90 to provide a face centered cubic structure that minimizes electromigration. Optionally, the middle layer is comprised of an Fe rich alloy such as FeCr, FeV, FeW, FeZr, FeNb, FeHf, or FeMo. EM performance is improved significantly compared to a spin valve with a conventional AP2 Co50Fe5 or Co75Fe25 single layer. The MR ratio of the spin valve is also increased and the RA is maintained at an acceptable level. The coupling layer is preferably Ru and the AP1 layer may be comprised of a lamination of CoFe and Cu layers as in [CoFe/Cu]2/CoFe.

Claims20

Dependent claims

A spin valve structure in a magnetic device, comprising:

(a) a pinned layer having an AP2/coupling/AP1 configuration wherein the AP2 portion is a FCC-like trilayer with an upper CoFe ferromagnetic layer having a first thickness, a lower ferromagnetic layer made of CoFe having a second thickness less than said first thickness, and a middle ferromagnetic layer comprised of an Fe rich alloy, said middle ferromagnetic layer contacts an upper surface of said lower CoFe ferromagnetic layer and said upper CoFe ferromagnetic layer contacts an upper surface of said middle ferromagnetic layer;
(b) a free layer;
and
(c) a non-magnetic spacer between the AP1 portion of said pinned layer and said free layer.

1 more element

Dependencies are inferred from the claim text.

FCC-like trilayer AP2 structure for CPP GMR EM improvement

Life of this patent

FCC-like trilayer AP2 structure for CPP GMR EM improvement

Life of this patent

Abstract

Claims20