Growth, structural, and magnetic properties of high coercivity Co/Pt multilayers

Journal Article · Fri Jun 01 04:00:00 EDT 2001 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.1363602· OSTI ID:40204108

Weller, D; Folks, L; Best, M; Fullerton, E E; Terris, B D; Kusinski, G J; Krishnan, K M; Thomas, G

Electron beam evaporated Co/Pt multilayers {l_brace}[Co(t{sub Co}nm)/Pt(1nm)]{sub 10}, 0.2{lt}t{sub Co}{lt}2 nm{r_brace} with perpendicular magnetic anisotropy and room temperature coercivities H{sub c}=2{endash}15 kOe are studied as a function of growth temperature T{sub G}. Hysteresis loops and magnetic force microscopy (MFM) indicate changes in the magnetization reversal mechanism along with a sharp increase in coercivity for T{sub G}{approx_gt}230{endash}250{degree}C. Films grown at T{sub G}{lt}230{degree}C (t{sub Co}=0.2{endash}0.4 nm) show micrometer size magnetic domains and rectangular hysteresis indicating magnetization reversal dominated by rapid domain wall motion following nucleation at H{sub n}{similar_to}H{sub c}. Films grown at T{sub G}{gt}250{degree}C show fine-grained MFM features on the sub-100-nm length scale indicating reversal dominated by localized switching of small clusters. High-resolution cross-sectional transmission electron microscopy (TEM) with elemental analysis shows columnar grains extending throughout the multilayer stack. Co depletion and structural defects at the grain boundaries provide a mechanism for exchange decoupling of adjacent grains, which may result in the high coercivities observed. {copyright} 2001 American Institute of Physics.

• Sponsoring Organization: (US)
• OSTI ID: 40204108
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 11 Vol. 89; ISSN 0021-8979
• Publisher: The American Physical Society
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANISOTROPY
DECOUPLING
DEFECTS
ELECTRON BEAMS
GRAIN BOUNDARIES
HYSTERESIS
MAGNETIC PROPERTIES
MAGNETIZATION
MICROSCOPY
NUCLEATION
PHYSICS
TRANSMISSION ELECTRON MICROSCOPY