liu.seSearch for publications in DiVA
Change search
ReferencesLink to record
Permanent link

Direct link
Influence of Ti layer thickness on solid state amorphization and magnetic properties of annealed Ti/Ni multilayer
Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
UGC-DAE Consortium for Scientific Research, Indore, India.
Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
2007 (English)In: Journal of Physics Condensed Matter, ISSN 0953-8984 (print), 1361-648X (online), Vol. 37, no 19, 376210- p.Article in journal (Refereed) Published
Abstract [en]

Annealing induced SSR (solid state reaction) leading to amorphization and magnetic properties as a function of Ti layer thickness has been investigated using XRD (x-ray diffraction), GIXRR (grazing incidence x-ray reflectivity) and MOKE (magneto-optical Kerr effect) measurements. [Ti(t Å)/Ni(50 Å)] × 10 ML samples where t = 30, 50 and 70 Å have been prepared by using electron beam evaporation technique under ultra-high vacuum conditions at room temperature. The amorphization process was carefully studied using XRD and GIXRR techniques showing that the SSA (solid state amorphization) temperature gradually decreases with increasing Ti layer thickness. Corresponding MOKE measurements show a magnetic to non-magnetic transition near the amorphization temperature (TA) with annealing, for each of the Ti layer thicknesses, due to crystalline Ti–Ni alloy phase formation at interfaces. The saturation magnetization and coercivity were also modified with Ti layer thickness variation. In addition to this, anisotropy developed with Ti layer thickness and diminished with increasing annealing temperatures. All these magnetic changes due to Ti layer thickness variations are interpreted in terms of amorphization and micro-structural changes near the SSA temperature.

Place, publisher, year, edition, pages
2007. Vol. 37, no 19, 376210- p.
National Category
Natural Sciences
URN: urn:nbn:se:liu:diva-13116DOI: 10.1088/0953-8984/19/37/376210OAI: diva2:17863
Available from: 2008-04-01 Created: 2008-04-01 Last updated: 2009-04-21
In thesis
1. Fabrication and study of inorganic and organic thin film magnets
Open this publication in new window or tab >>Fabrication and study of inorganic and organic thin film magnets
2007 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Thin film magnets are very important for many kinds of electronic devices and play a crucial role to achieve optimum performance. Therefore an intense level of research is going on all around the world to fabricate advanced electronics devices using both new inorganic and organic thin-film magnets. Historically, most magnetic materials used for technological applications are based on inorganic materials and have been studied extensible up to now. Recently, however, organic or molecular magnets have opened a new prospective of thin film magnets which have begun to show promise, offering the possibility of light-weight flexible materials and devices that include magnetic functionality.

The research presented in this thesis is hence divided into two parts, where inorganic and organic magnets in thin films form were studied. The Ti/Ni multilayer system is studied as an inorganic magnet in the first part, whereas M(TCNE)x thin films were studied in the second part with M= Fe, Ni and TCNE is tetracynoethelene, an organic compound, and x~2.

The Ti/Ni multilayer is a potential candidate for industrial applications and also features solid-state amorphisation. Because of various interesting scientific and technological aspects of Ti/Ni multilayer structures, many structural properties and subsequent thermal stability studies have been extensively reported in the literature, but surprisingly few reports are available on the corresponding electronic and magnetic properties. The work in the present thesis is therefore focused on synthesis and systematic investigation of structural, electronic and magnetic properties of as prepared as well as annealed Ti/Ni multilayer structures and to establish correlation between them.

The second part of the thesis deals with organic-based molecular magnets of the M(TCNE)x type, where x~2, M = Fe, Ni and TCNE = tetracynoethelene. Fe(TCNE)x and Ni(TCNE)x have for the first time been fabricated as thin films, free of oxygen- and precursor-induced defects. The films were fabricated in situ under ultra high vacuum conditions using our group’s recently developed fabrication techniques for organic-based molecular magnets. The previously unknown electronic structure of these thin film magnets are presented in the thesis. Room temperature magnetic ordering was observed for thin films of Ni(TCNE)2, in stark contrast to earlier versions of the material (fabricated with the old methods and hence containing various defects). Room temperature magnetic ordering for a similar system, Ni2(TCNE), previously has been reported by another group, but it is clear that more studies are necessary to completely resolve the underlying mechanisms for the magnetic properties seen in these materials.

Place, publisher, year, edition, pages
Linköping: Institutionen för teknik och naturvetenskap, 2007. 65 p.
Linköping Studies in Science and Technology. Dissertations, ISSN 0345-7524 ; 1152
Physics, electronic, thin films, inorganic magnets, organic magnets
National Category
Physical Sciences
urn:nbn:se:liu:diva-11442 (URN)978-91-85895-20-5 (ISBN)
Public defence
2007-12-14, K3, Kåkenhus, Campus Norrköping, Linköpings universitet, Norrköping, 10:15 (English)
Available from: 2008-04-01 Created: 2008-04-01 Last updated: 2012-11-21

Open Access in DiVA

No full text

Other links

Publisher's full textLink to Ph.D. thesis

Search in DiVA

By author/editor
Bhatt, PramondFahlman, Mats
By organisation
Department of Science and TechnologyThe Institute of Technology
Natural Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 32 hits
ReferencesLink to record
Permanent link

Direct link