Patent ID: 7084467

Claim:
A spin valve transistor comprising: an emitter; a collector; a base between the emitter and the collector; a spin valve including: a ferromagnetic free layer structure composed of iron (Fe); a self-pinned antiparallel (AP) pinned layer structure; a nonmagnetic spacer layer between the free layer structure and the AP pinned layer structure; and the free layer structure interfacing the spacer layer; the base comprising at least said free layer structure; the self pinned AP pinned layer structure including: a ferromagnetic first antiparallel (AP) pinned layer; a ferromagnetic second antiparallel (AP) pinned layer; and a nonmagnetic antiparallel coupling (APC) layer located between the first and second AP pinned layers; the first AP pinned layer being composed of iron (Fe) and interfacing the spacer layer; the second AP pinned layer including: an iron (Fe) film; a cobalt iron (CoFe) film with a positive magnetostriction; the iron (Fe) film being located between and interfacing the APC layer and the cobalt iron (CoFe) film; and the CoFe film having a magnetostrictive anisotropy field that is oriented perpendicular to a head surface of the spin valve transistor for self pinning the AP pinned layer structure.