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dc.contributor.authorMartínez Viviente, Félix Lorenzo 
dc.contributor.authorToledano Luque, María 
dc.contributor.authorGandía Alabau, José Javier 
dc.contributor.authorCárabe López, Julio 
dc.contributor.authorBohne, Wolfgang 
dc.contributor.authorRöhrich, J. 
dc.contributor.authorStrub, Erik 
dc.contributor.authorMártil de la Plaza, Ignacio 
dc.date.accessioned2011-11-16T07:42:24Z
dc.date.available2011-11-16T07:42:24Z
dc.date.issued2007-08-16
dc.identifier.citationMartínez Viviente, Félix Lorenzo. Optical properties and structure of HfO2 thin films grown by high pressure reactive sputtering. Journal of Physics D: Applied Physics, 40 (17): 5256-5265, agosto 2007. ISSN 0022-3727eng
dc.identifier.isbn0022-3727
dc.description.abstractThin films of hafnium oxide have been grown by high pressure reactive sputtering on transparent quartz substrates (UV-grade silica) and silicon wafers. Deposition conditions were adjusted to obtain as well as amorphous films. Optical properties of the films deposited on the silica substrates were investigated by transmittance and reflectance spectroscopy in the ultraviolet, visible and near infrared range (UV-VIS-NIR). A numerical analysis method that takes into account the different surface roughness of the polycrystalline and amorphous films was applied to calculate the optical constants (refractive index and absorption coefficient). Amorphous films were found to have a higher refractive index and a lower transparency than polycrystalline films. This is attributed to a higher density of the amorphous samples, which was confirmed by atomic density measurements performed by heavy-ion elastic recoil detection analysis (ERDA). The absorption coefficient gave an excellent fit to the Tauc law (indirect gap), which allowed to obtain a band gap value of 5.54 eV. The structure of the films (amorphous or polycrystalline) was found to have no significant influence on the nature of the band gap. The Tauc plots also give information about the structure of the films, because the slope of the plot (the Tauc parameter) is related to the degree of order in the bond network. The amorphous samples had a larger value of the Tauc parameter, i.e., more order than the polycrystalline samples. This is indicative of a uniform bond network with percolation of the bond chains, in contrast to the randomly oriented polycrystalline grains separated by grain boundaries.eng
dc.formatapplication/pdfeng
dc.language.isoengeng
dc.publisherIOPeng
dc.rightsLicencia Creative Commonseng
dc.titleOptical properties and structure of HfO2 thin films grown by high pressure reactive sputteringeng
dc.typeinfo:eu-repo/semantics/articleeng
dc.subject.otherElectrónicaeng
dc.subjectAmorphous filmseng
dc.subjectQuartz substrateseng
dc.subjectPolycrystallineeng
dc.subjectThin filmseng
dc.identifier.urihttp://hdl.handle.net/10317/1921
dc.peerreviewSieng
dc.identifier.doi10.1088/0022-3727/40/17/037
dc.rights.accessRightsinfo:eu-repo/semantics/openAccesseng
dc.type.versioninfo:eu-repo/semantics/publishedVersioneng


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