Co/Pt multilayer-based magnetic tunnel junctions with perpendicular magnetic anisotropy

Abstract

Temperature-dependent transport measurements of magnetic tunnel junctions with perpendicularly magnetized Co/Pt electrodes are presented. Magnetization measurements of the Co/Pt multilayers are performed to characterize the electrodes. The interface magnetization of the Co layers at the Pt interface is estimated in dependence of the annealing temperature. The effect of the annealing temperature on the tunneling magnetoresistance effect of the magnetic tunnel junctions (MTJs) is investigated. Tunneling magnetoresistance ratios of about 19% at room temperature are attained and two well-defined switching fields are observed. The tunneling magnetoresistance of Co/Pt based tunnel junctions changes by a factor of 1.9 if cooled to 13 K. The results are compared to measurements of MTJs with Co-Fe-B electrodes and in-plane anisotropy.