Investigation of Magnetoresistive Characteristics of Metallic Multilayers Comprising Ru-Based Synthetic Antiferromagnetic Layers

Synthetic antiferromagnet-based spin-valve (SAF-SV) structures were prepared and tested by varying Δt (= t_P2-t_P1), where t_P1 and t_P2 are the thicknesses of the first and the second pinning layers, respectively. Only samples with positive At values have been characterized because negative At results in a less useful inverse magnetoresistance. Though three materials (NiFe, Cu, and Ru) were tested as candidates for the seedlayer in bottom structures, almost no difference was found in terms of microstructure. A detailed explanation of magnetization reversal in SAF-SV structures was given to better understand the magneto-transport mechanism, including the appearance of sub- peaks, Presumably, about 0.5 nm of atomic intermixing might happened in the bottom SAF-SV structure with Δt = 1.5 nm.