Effect of ion beam mixing on microstructure and magnetic properties of Gd-Co multilayer films

Abstract

This work investigated the effect of ion beam mixing on the magnetic and structural characteristics of Gd-Co multilayer films. Multilayer films with bilayer periods (BP) from 10 to 300 Å were mixed by 150 to 300 keV Ar+ ion doses of 1016 cm−2. The magnetizations of the as-deposited multilayers were dominated by oxidation, and by the asymmetric redistribution of Co atoms. Ion beam mixing eliminated much of these effects, but the degree was strongly dependent on the layer thickness. The small BP films were completely mixed, with amorphous nanoparticles, but the large BP films contained small, microcrystals in an amorphous matrix due to incomplete mixing. The magnetic moment of ion beam mixed films were strongly dependent on the ion beam energy and the layer thickness.