Microstructural investigation of Cu/Co multilayer films

D. J. Larson; A. K. Petford-Long; A. Cerezo

doi:10.1016/S0921-5093(99)00240-3

Microstructural investigation of Cu/Co multilayer films

D. J. Larson, A. K. Petford-Long, A. Cerezo^*

^*Corresponding author for this work

Materials Science and Engineering

Research output: Contribution to journal › Article › peer-review

11 Scopus citations

Abstract

Multilayer film structures, with applications based on the giant-magnetoresistance principle, comprise an exciting area of research and have the capability to improve the storage density and sensitivity of devices used by the magnetic recording industry. In order to optimise the performance of these devices, it is imperative to characterise the atomic-level structural and compositional variations as a function of processing and operating conditions. A new technique, based on focused ion-beam milling, has been developed to fabricate field-ion specimens from nanometer-scale multilayer films deposited directly onto a planar substrate. This method has allowed field-ion microscopy and three-dimensional atom-probe analysis of this type of structure for the first time. A multilayer thin film structure containing 100 repetitions of a (Cu_2nm/Co_2nm) bilayer showed 5-20% Cu alloying in the cobalt layers, a high degree of layer curvature (particularly at grain boundaries) and regions where several cobalt layers appear to be in contact. These observations suggest a degree of ferromagnetic coupling, which explains the relatively high coercivity measurements obtained from the same Cu/Co films. Films which were annealed for 1 h at 360°C showed an increase in grain size, but little change in other microstructural properties.

Original language	English (US)
Pages (from-to)	69-74
Number of pages	6
Journal	Materials Science and Engineering: A
Volume	270
Issue number	1
DOIs	https://doi.org/10.1016/S0921-5093(99)00240-3
State	Published - Sep 15 1999

Funding

The authors would like to thank Dr D. T. Foord at the University of Cambridge for assistance with the focused ion-beam milling, T.J. Godfrey for technical assistance, Drs. P.J. Warren, M. Huang, G. D.W. Smith and M.K. Miller for helpful discussions and Dr T.C. Anthony of Hewlett Packard for provision of the Cu/Co multilayer devices, which were provided as part of a collaborative project with the University of Oxford. This research was sponsored by the US National Science Foundation under Grant No. INT-9600327 (DJL) and by The Royal Society (AKPL).

Keywords

Cu/Co multilayers
Focused
Giant magnetoresistance
Ion-beam milling
Multilayer films

ASJC Scopus subject areas

General Materials Science
Condensed Matter Physics
Mechanics of Materials
Mechanical Engineering

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10.1016/S0921-5093(99)00240-3

Cite this

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title = "Microstructural investigation of Cu/Co multilayer films",

abstract = "Multilayer film structures, with applications based on the giant-magnetoresistance principle, comprise an exciting area of research and have the capability to improve the storage density and sensitivity of devices used by the magnetic recording industry. In order to optimise the performance of these devices, it is imperative to characterise the atomic-level structural and compositional variations as a function of processing and operating conditions. A new technique, based on focused ion-beam milling, has been developed to fabricate field-ion specimens from nanometer-scale multilayer films deposited directly onto a planar substrate. This method has allowed field-ion microscopy and three-dimensional atom-probe analysis of this type of structure for the first time. A multilayer thin film structure containing 100 repetitions of a (Cu2nm/Co2nm) bilayer showed 5-20% Cu alloying in the cobalt layers, a high degree of layer curvature (particularly at grain boundaries) and regions where several cobalt layers appear to be in contact. These observations suggest a degree of ferromagnetic coupling, which explains the relatively high coercivity measurements obtained from the same Cu/Co films. Films which were annealed for 1 h at 360°C showed an increase in grain size, but little change in other microstructural properties.",

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author = "Larson, {D. J.} and Petford-Long, {A. K.} and A. Cerezo",

note = "Funding Information: The authors would like to thank Dr D. T. Foord at the University of Cambridge for assistance with the focused ion-beam milling, T.J. Godfrey for technical assistance, Drs. P.J. Warren, M. Huang, G. D.W. Smith and M.K. Miller for helpful discussions and Dr T.C. Anthony of Hewlett Packard for provision of the Cu/Co multilayer devices, which were provided as part of a collaborative project with the University of Oxford. This research was sponsored by the US National Science Foundation under Grant No. INT-9600327 (DJL) and by The Royal Society (AKPL). ",

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Microstructural investigation of Cu/Co multilayer films

Abstract

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Keywords

ASJC Scopus subject areas

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