High magnetoresistive sensitivity in electrodeposited FeCoNi∕Cu multilayers

Abstract

Fe Co Ni ∕ Cu multilayers with large magnetoresistive sensitivity at low field have been electrodeposited on n-type Si from a single electrolyte by modulating the deposition potential. Dissolution of the ferromagnetic (FM) layer during copper deposition was minimized and interface sharpness was improved by monitoring the current transients during the transition from FM to Cu deposition and using these data to fine tune the Cu deposition potential and Fe2+ concentration in the electrolyte. Using optimal processing parameters, a maximum giant magnetoresistance (GMR) ratio above 9% could be obtained. Maximum GMR sensitivity of over 0.11%∕Oe was achieved in the field range 5–15Oe.