Temperature and bias voltage dependence of Co/Pd multilayer-based magnetic tunnel junctions with perpendicular magnetic anisotropy

TL;DR

This study investigates how temperature and bias voltage influence the electrical transport and magnetic properties of Co/Pd multilayer-based magnetic tunnel junctions with perpendicular magnetic anisotropy, revealing key factors affecting TMR performance.

Contribution

It provides new insights into the dependence of TMR effects on layer thickness, annealing, and interface composition in Co/Pd-based MTJs with perpendicular anisotropy.

Findings

TMR ratios of about 11% at room temperature and 18.5% at 13 K.

Identification of two well-defined switching fields.

Comparison showing differences with Co-Fe-B in-plane MTJs.

Abstract

Temperature- and bias voltage-dependent transport measurements of magnetic tunnel junctions (MTJs) with perpendicularly magnetized Co/Pd electrodes are presented. Magnetization measurements of the Co/Pd multilayers are performed to characterize the electrodes. The effects of the Co layer thickness in the Co/Pd bilayers, the annealing temperature, the Co thickness at the MgO barrier interface, and the number of bilayers on the tunneling magneto resistance (TMR) effect are investigated. TMR-ratios of about 11 % at room temperature and 18.5 % at 13 K are measured and two well-defined switching fields are observed. The results are compared to measurements of MTJs with Co-Fe-B electrodes and in-plane anisotropy.