Domain structure and perpendicular magnetic anisotropy in CoFe/Pd multilayers using off-axis electron holography

TL;DR

This study investigates how the layer thickness in CoFe/Pd multilayers influences magnetic domain structures and perpendicular magnetic anisotropy, revealing that thinner layers enhance PMA and reduce domain size.

Contribution

It provides detailed insights into the relationship between layer thickness and magnetic properties in CoFe/Pd multilayers using off-axis electron holography.

Findings

Thinner magnetic layers exhibit stronger perpendicular magnetic anisotropy.

Magnetic domain size decreases with decreasing layer thickness.

Layer thickness is the primary factor affecting magnetic properties.

Abstract

Multilayers of Co90Fe10/Pd with different bilayer thicknesses, have been deposited by dc-magnetron sputtering on thermally oxidized Si wafers. Transmission electron microscopy showed that the highly textured crystalline films had columnar structure, while scanning transmission electron microscopy and atomic force microscopy respectively indicated some layer waviness and surface roughness. The magnetic domain structure and perpendicular magnetic anisotropy (PMA) of the Co90Fe10/Pd multilayers were investigated by off-axis electron holography and magnetic force microscopy. The Co90Fe10 layer thickness was the primary factor determining the magnetic domain size and the perpendicular magnetization: both decreased as the thickness increased. The strongest PMA was observed in the sample with the thinnest magnetic layer of 0.45 nm.