Magnetoresistive sensitivity and uniaxial anisotropy of spin-valve microstrips with a synthetic antiferromagnet

Abstract

Microobjects (strips) were formed by contact photolithography using Та/Ni₈₀Fe₂₀/Co₉₀Fe₁₀/Cu/Co₉₀Fe₁₀/Ru/Co₉₀Fe₁₀/Fe₅₀Mn₅₀/Ta spin-valves prepared by magnetron sputtering. A mutually perpendicular arrangement of uniaxial and unidirectional anisotropy axes in microobjects has been formed using two different thermomagnetic treatment regimes. The magnetoresistive sensitivity of spin valve and spin-valve-based microobject has been found to depend on the mutual arrangement of the easy magnetization axis and direction of magnetic field applied upon thermomagnetic treatment. The obtained data have been interpreted taking into account changes in the induced anisotropy and anisotropy due to the shape of the microobject.