Microstructure and magnetic properties of Co/Pd multilayered thin films with C or Si seedlayer

Abstract

Microstructure and magnetic properties of sputter deposited Co/Pd multilayered perpendicular magnetization films with amorphous C or Si seedlayer were investigated. The angstrom scale surface roughness of the seedlayer causes fine crystal grains to form in the Co/Pd multilayer and to decrease the extent of intergranular exchange coupling, while it obstructs the formation of a regular interface between Co and Pd layers. The Si seedlayer, which exhibits a surface roughness lower than the C seedlayer, yields Co/Pd multilayered films with the lowest intergranular exchange coupling and the highest coercivity. The improvement in magnetic properties of the Co/Pd film with Si seedlayer is attributable mainly to the formation of Pd2Si at the interface between the Co/Pd layer and the Si seedlayer. The Pd2Si provides suitable nucleation sites for the grain growth of Co/Pd multilayered film that can be utilized as a perpendicular magnetic recording medium.

Soft x-ray magnetic circular dichroism study of [Co/Pd] multilayered perpendicular magnetic films

“…[9][10][11]13 Onoue et al reported that an increase in the thickness of amorphous C or Si seedlayer greatly enhanced the perpendicular coercivity (H c ) and the nucleation field of reversed magnetic domains. [20][21][22][23][24] They also reported that the seedlayer reduces the intergranular exchange coupling and magnetic domain size of the media, resulting in an improvement of signal-to-noise ratio in their read-write ͑R/W͒ experiment, and that an amorphous C or Si seedlayer is useful for the ͓Co/Pd͔ 20 media. The increase in the thickness of C or Si seedlayer leads to improvements in recording performance, but it accompanies a decrease in K u .…”

Preparation and Characterization of Ni or Co/Cu Multilayer Nanowires

“…Ferromagnetic nanowires synthesized by various methods, [1][2][3] exhibit unique and tuneable magnetic properties due to the inherent shape anisotropy and the small wire dimensions. These nanomaterials exhibit unique magnetic properties for further application, such as high squareness and high coercivity.…”

Highly ordered magnetic multilayer Ni/Cu nanowires

“…Ferromagnetic nanowires synthesized by various methods [1][2][3], exhibit unique and tuneable magnetic properties due to the inherent shape anisotropy and the small wire dimensions. These nanomaterials exhibit unique magnetic properties for further application, such as high squareness and high coercivity [4].…”