File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Article: Annealing effect of NiO/Co90Fe10 thin films: From bilayer to nanocomposite

TitleAnnealing effect of NiO/Co90Fe10 thin films: From bilayer to nanocomposite
Authors
KeywordsExchange bias
Magnetic thin film
Nanocomposite
Issue Date2018
PublisherElsevier BV.
Citation
Physics Letters A: General, Atomic and Solid State Physics, 2018, v. 382 n. 39, p. 2886-2893 How to Cite?
AbstractExchange-biased bilayers are widely used in the pinned layers of spintronic devices. While magnetic field annealing (MFA) was routinely engaged during the fabrication of these devices, the annealing effect of NiO/CoFe bilayers is not yet reported. In this paper, the transition from NiO/Co90Fe10 bilayer to nanocomposite single layer was observed through rapid thermal annealing at different temperatures under magnetic field. The as-deposited and low-temperature (<623 K) annealed samples had rock salt (NiO) and face center cubic (Co90Fe10) structures. On the other hand, annealing at 623 K and 673 K resulted in nanocomposite single layers composed of oxides (matrix) and alloys (precipitate), due to grain boundary oxidization and strong interdiffusion in the NiO/CoFe and CoFe/SiO2 interfaces. The structural transition was accompanied by the reduction of grain sizes, re-ordering of crystallites, incensement of roughness, and reduction of Ni2+. When measured at room temperature, the bilayers exhibited soft magnetism with small room-temperature coercivity. The nanocomposite layers exhibited an enhanced coercivity due to the changes in the magnetization reversal mechanism by pinning from the oxides. At 10 K, the increased antiferromagnetic anisotropy in the NiO resulted in enhanced coercivity and exchange bias in the bilayers. The nanocomposites exhibited weaker exchange bias compared with the bilayers due to frustrated interfacial spins. This investigation on how the magnetic properties of exchange-biased bilayers are influenced by magnetic RTA provides insights into controlling the magnetization reversal properties of thin films.
Persistent Identifierhttp://hdl.handle.net/10722/259264
ISSN
2017 Impact Factor: 1.863
2015 SCImago Journal Rankings: 0.755

 

DC FieldValueLanguage
dc.contributor.authorLi, X-
dc.contributor.authorChang, YC-
dc.contributor.authorChen, JY-
dc.contributor.authorLin, KW-
dc.contributor.authorDesautels, RD-
dc.contributor.authorvan Lierop, J-
dc.contributor.authorPong, PWT-
dc.date.accessioned2018-09-03T04:04:05Z-
dc.date.available2018-09-03T04:04:05Z-
dc.date.issued2018-
dc.identifier.citationPhysics Letters A: General, Atomic and Solid State Physics, 2018, v. 382 n. 39, p. 2886-2893-
dc.identifier.issn0375-9601-
dc.identifier.urihttp://hdl.handle.net/10722/259264-
dc.description.abstractExchange-biased bilayers are widely used in the pinned layers of spintronic devices. While magnetic field annealing (MFA) was routinely engaged during the fabrication of these devices, the annealing effect of NiO/CoFe bilayers is not yet reported. In this paper, the transition from NiO/Co90Fe10 bilayer to nanocomposite single layer was observed through rapid thermal annealing at different temperatures under magnetic field. The as-deposited and low-temperature (<623 K) annealed samples had rock salt (NiO) and face center cubic (Co90Fe10) structures. On the other hand, annealing at 623 K and 673 K resulted in nanocomposite single layers composed of oxides (matrix) and alloys (precipitate), due to grain boundary oxidization and strong interdiffusion in the NiO/CoFe and CoFe/SiO2 interfaces. The structural transition was accompanied by the reduction of grain sizes, re-ordering of crystallites, incensement of roughness, and reduction of Ni2+. When measured at room temperature, the bilayers exhibited soft magnetism with small room-temperature coercivity. The nanocomposite layers exhibited an enhanced coercivity due to the changes in the magnetization reversal mechanism by pinning from the oxides. At 10 K, the increased antiferromagnetic anisotropy in the NiO resulted in enhanced coercivity and exchange bias in the bilayers. The nanocomposites exhibited weaker exchange bias compared with the bilayers due to frustrated interfacial spins. This investigation on how the magnetic properties of exchange-biased bilayers are influenced by magnetic RTA provides insights into controlling the magnetization reversal properties of thin films.-
dc.languageeng-
dc.publisherElsevier BV.-
dc.relation.ispartofPhysics Letters A: General, Atomic and Solid State Physics-
dc.subjectExchange bias-
dc.subjectMagnetic thin film-
dc.subjectNanocomposite-
dc.titleAnnealing effect of NiO/Co90Fe10 thin films: From bilayer to nanocomposite-
dc.typeArticle-
dc.identifier.emailPong, PWT: ppong@hkucc.hku.hk-
dc.identifier.authorityPong, PWT=rp00217-
dc.description.naturelink_to_subscribed_fulltext-
dc.identifier.doi10.1016/j.physleta.2018.07.018-
dc.identifier.scopuseid_2-s2.0-85051362396-
dc.identifier.hkuros288667-
dc.identifier.volume382-
dc.identifier.issue39-
dc.identifier.spage2886-
dc.identifier.epage2893-
dc.publisher.placeNetherlands-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats