Correlation between Pd metal thickness and thermally stable perpendicular magnetic anisotropy features in [Co/Pd]n multilayers at annealing temperatures up to 500 °C

Abstract

We examine highly stable perpendicular magnetic anisotropy (PMA) features of [Co/Pd]10 multilayers (MLs) versus Pd thickness at various ex-situ annealing temperatures. Thermally stable PMA characteristics were observed up to 500 °C, confirming the suitability of these systems for industrial applications at this temperature. Experimental observations suggest that the choice of equivalent Co and Pd layer thicknesses in a ML configuration ensures thermally stable PMA features, even at higher annealing temperatures. X-ray diffraction patterns and cross-sectional transmission electron microscopy images were obtained to determine thickness, post-annealing PMA behavior, and to explore the structural features that govern these findings.

Observation of magnetic skyrmions in unpatterned symmetric multilayers at room temperature and zero magnetic field

“…To extract the perpendicular magnetic anisotropy, we used , which gives ≈ 0.06 MJ·m −3 . In a recent work, effective perpendicular anisotropy obtained for Co/Pd multilayes, similar values of PMA were obtained when the Pd layer is thicker than 0.9 nm 40 , 41 . We varied the magnetization saturation M s and magnetic anisotropy to understand the impact of these properties on the skyrmions stability considering a weak Dzyaloshinskii-Moriya below D = 0.8 mJ·m −2 .…”

Structural and morphological effect of Ti underlayer on Pt/Co/Pt magnetic ultra-thin film

“…In multilayered PMA film (FM/HM multilayers and HM/ FM/HM trilayers), the interface anisotropy responsible for the PMA. Generally, strong spin-orbit coupling at FM and HM interface causes PMA, and PMA strongly depends on FM and HM layer thicknesses [13,18,19], growth parameters [20][21][22][23], and structural parameters such as surface roughness [2,24], diffusion [9,25,26], and strain [8,27,28]. Also, it's well known that the textured growth in fcc (111) orientation helps to promote/enhance PMA, and it can be achieved by inserting underlayers/buffer layer such as Pt, Ta, and TaOx as a template for crystalline growth between the substrate and the bottom layer [8,13,21,23,29,30].…”

Annealing effect on interlayer exchange coupling in perpendicularly magnetized synthetic antiferromagnetic structure based on Co/Pd multilayers with ultrathin Ru spacer

“…The K u values obtained in this study were comparable to those of Co=Pd multilayers in other reports. 14,15) These changes in K u and M s t with respect to T a should originate from the intermixing of atoms at the multilayer interface during annealing. 15) We confirmed that our Co=Pd multilayer remains perpendicularly magnetized up to T a = 350 °C but that K u and M s t are not constant owing to the annealing effect.…”

“…10) This Ru thickness, which is less than 0.5 nm, corresponds to the first peak of the oscillation of the interlayer exchange coupling, leading to the highest J ex (largest H ex ). 13) A Co=Pd multilayer, which is also one of the Co-based multilayers, 14,15) is another candidate material for expanding one's options for p-SAF structures. There have been a few reports on [Co=Pd]-based p-SAF structures with such an ultrathin Ru spacer to date.…”