Characterization of ( Pt 2   nm / Co 0.4   nm ) 3 / Pt x / IrMn 7   nm multilayersby tomographic atom probe: On the role of a Pt spacer

• Published in: Journal of applied physics 2009-05, Vol.105 (10), p.103912-103912-5
• Main Authors: Zarefy, A., Lardé, R., Lechevallier, L., Cuvilly, F., Le Breton, J. M., Baltz, V., Rodmacq, B., Dieny, B.
• Format: Article
• ISSN: 0021-8979; 1089-7550
• DOI: 10.1063/1.3125527

Structural investigation of Ta 3   nm / [ ( Pt 2   nm / Co 0.4   nm ) 3 / Pt x / IrMn 7   nm ] 7 / Pt 10   nm multilayers without ( x = 0   nm ) and with ( x = 0.4   nm ) a Pt spacer has been performed by laser-assisted tomographic atom probe. Without a Pt spacer a strong intermixing is observed at the Co/IrMn interface. In the multilayer containing a Pt spacer the Co/Pt/IrMn interface is very weakly intermixed. It thus appears that the Pt spacer acts as a diffusion barrier that prevents the Ir and Mn atoms from diffusing into the Co layer. The consequences of this effect on the magnetic properties are discussed. The exchange bias field and the anisotropy direction of these two multilayers are analyzed and correlated with the structural investigation.