Magnetic properties of antiferromagnetically coupled CoFeB/Ru/CoFeB

TL;DR

This study investigates the thermal stability and magnetic properties of amorphous CoFeB layers coupled antiferromagnetically through a Ru interlayer, highlighting their stability up to high annealing temperatures.

Contribution

It provides new insights into the thermal stability and magnetic behavior of CoFeB/Ru/CoFeB structures under annealing conditions.

Findings

Saturation field remains stable up to 300°C annealing.

Coercivity increases significantly after 325°C, indicating crystallization.

Antiferromagnetic coupling is maintained at high temperatures.

Abstract

This work reports on the thermal stability of two amorphous CoFeB layers coupled antiferromagnetically via a thin Ru interlayer. The saturation field of the artificial ferrimagnet which is determined by the coupling, J, is almost independent on the annealing temperature up to more than 300 degree C. An annealing at more than 325 degree C significantly increases the coercivity, Hc, indicating the onset of crystallization.