Patent ID: 7768749

Claim:
A tunnel magnetoresistive (TMR) device comprising: a pinned ferromagnetic layer having a magnetization substantially prevented from rotation in the presence of an applied magnetic field; an insulating tunnel barrier layer on the pinned layer; and a free ferromagnetic stack on the tunnel barrier layer and having at least one magnetization substantially free to rotate in the presence of an applied magnetic field, the free ferromagnetic stack having at least one free stack sublayer, wherein the free stack sublayer is an upper free stack sublayer and the free ferromagnetic stack comprises a lower free stack sublayer, a spacer layer being disposed between the free stack sublayers, the spacer layer not extending completely to ends defined by the lower free stack sublayer, and further wherein an upper bias layer is disposed on the upper free stack sublayer, the upper free stack sublayer and upper bias layer not extending to the ends of the lower free stack sublayer.