X-ray analysis of praseodymia

Bitte benutzen Sie diese Kennung, um auf die Ressource zu verweisen:
https://osnadocs.ub.uni-osnabrueck.de/handle/urn:nbn:de:gbv:700-2009111311
Open Access logo originally created by the Public Library of Science (PLoS)
Langanzeige der Metadaten
DC ElementWertSprache
dc.contributor.advisorProf. Dr. Joachim Wollschläger
dc.creatorWeisemöller, Thomas
dc.date.accessioned2010-01-30T14:38:14Z
dc.date.available2010-01-30T14:38:14Z
dc.date.issued2009-11-11T13:28:25Z
dc.date.submitted2009-11-11T13:28:25Z
dc.identifier.urihttps://osnadocs.ub.uni-osnabrueck.de/handle/urn:nbn:de:gbv:700-2009111311-
dc.description.abstractIn this thesis, it was shown that thin films of hexagonal praseodymium sesquioxide on Si(111) can be transformed to B-oriented twin free films of cubic praseodymium dioxide with oxygen vacancies by post deposition annealing in 1 atm. oxygen at temperatures from 300°C up to 700°C for 30 minutes. Films annealed at 100°C and 200°C are still purely hexagonal praseodymium sesquioxide after the annealing process. In the transformed films, two stoichiometric phases coexist laterally. The lateral lattice constant of both species is almost identical to the one of the originally deposited hexagonal praseodymium sesquioxide. Therefore, we assume that the lateral lattice constant is pinned throughout the oxidation process.The species are hence strained and show different vertical lattice constants, depending on the amount of oxygen vacancies. In some samples, those vacancies were partly ordered vertically, leading to a unit cell twice as large as expected for stoichiometric praseodymium dioxide.During the annealing process, an amorphous interfacial layer between substrate and oxide was detected. While the existence of this layer was known before, it was possible for the first time to quantify the thickness of the praseodymium rich part of this interface for epitaxially grown films. It was shown that this layer starts to grow significantly only during post deposition annealing at 500°C or more.These and other results for thin films were connected to previously published data for bulk praseodymia. The multi column model mentioned above for laterally coexisting praseodymia species in thin films was backed up by powder data. As a matter of fact, it was shown that this coexistence of several praseodymia species can be expected to be the rule rather than the exception.Strong evidence was found that results interpreted previously as stoichiometric cubic praseodymium sesquioxide contain more oxygen than originally thought...eng
dc.language.isoeng
dc.subjectpraseodymium
dc.subjectpraseodymium oxide
dc.subjectSi(111)
dc.subjectsilicon
dc.subjectXRD
dc.subjectX-ray diffraction
dc.subjectthin films
dc.subjecttwo column model
dc.subjectamorphous interface layer
dc.subject.ddc540 - Chemieger
dc.titleX-ray analysis of praseodymiaeng
dc.typeDissertation oder Habilitation [doctoralThesis]-
thesis.locationOsnabrück-
thesis.institutionUniversität-
thesis.typeDissertation [thesis.doctoral]-
thesis.date2009-08-07T12:00:00Z-
elib.elibid952-
elib.marc.edtjost-
elib.dct.accessRightsa-
elib.dct.created2009-10-21T13:10:40Z-
elib.dct.modified2009-11-11T13:28:25Z-
dc.contributor.refereeapl. Prof. Prof. h.c. Dr. Dr. h.c. Manfred Neumann
dc.subject.dnb29 - Physik, Astronomieger
dc.subject.pacs68.55.ajeng
dc.subject.pacs61.72.jdeng
dc.subject.pacs81.15.Hi - Molecular, atomic, ion, and chemical beam epitaxyeng
dc.subject.pacs61.66.Fn - Inorganic compoundseng
dc.subject.pacs61.05.cceng
dc.subject.pacs61.05.cpeng
dc.subject.pacs77.55. feng
vCard.ORGFB4ger
Enthalten in den Sammlungen:FB06 - E-Dissertationen

Dateien zu dieser Ressource:
Datei Beschreibung GrößeFormat 
E-Diss952_thesis.pdfPräsentationsformat8,77 MBAdobe PDF
E-Diss952_thesis.pdf
Miniaturbild
Öffnen/Anzeigen


Alle Ressourcen im Repositorium osnaDocs sind urheberrechtlich geschützt, soweit nicht anderweitig angezeigt. rightsstatements.org