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dc.contributor.advisorCaruso, Anthony N.eng
dc.contributor.authorDriver, Marcus Skyeng
dc.date.issued2013eng
dc.descriptionTitle from PDF of title page, viewed on April 1, 2014eng
dc.description2013 Falleng
dc.descriptionDissertation advisor: Anthony Carusoeng
dc.descriptionVitaeng
dc.descriptionThesis (Ph. D.)--Dept. of Physics and Dept. of Chemistry. University of Missouri--Kansas City, 2013eng
dc.description.abstractThe chemical and electronic structure, as related to the surface, interface and bulk of amorphous hydrogenated boron carbide (a-BxC:Hy), is of interest in neutron detection and microelectronics. This dissertation investigates the chemical and electronic structure of semiconducting thin-film a-BxC:Hy grown by plasma enhanced chemical vapor deposition (PECVD) of ortho-carborane (1,2-C2B10H12). Experimental methods used include: x-ray and ultraviolet photoelectron spectroscopies (XPS/UPS) and x-ray absorption/emission spectroscopies (XAS/XES). These methods were used to investigate the chemical species, bonding and hybridizations, and band gaps of a-BxC:Hy prepared or treated under varying conditions. Additionally, a detailed examination of the formation of Schottky barriers was implemented. Throughout this dissertation the chemical structure was studied. One study was to understand various growth conditions. The effects of the PECVD growth parameters were evaluated by comparing changes in atomic percentages (at.%’s) between thin-films from various substrate temperatures. Additionally, detailed studies of the photoelectron core level under two different growth conditions were undertaken to evaluate the effects of pre-/post- argon ion etching (Ar+) for the following: the chemical structural change for both an as grown (AG) and in-situ thermal treatment (500°C), and post Ar+ etch of samples thermally treated ranging from as grown to 850°C. The as grown and in-situ treated samples were used in conjunction to determine the formation of the Schottky barrier. The electronic structure was determined by the changes within the valence band of the thermally treated samples and formation of Schottky barrier. Thermally treated samples (as grown to 850°C) were further evaluated with respect to their occupied and unoccupied electronic states. The atomic percentage gave a stoichiometry range for a-BxC:Hy (given as x=1.5 to 3.0 with y= decreases with thermal treatment and Oz: z= 0.2 to 0.5). Studies of films with respect to thermal treatment reveal two discrete state changes that occur at 400°C and 850°C. These changes are due to segregation of carbon and oxygen by the reorganization of the hydrocarbon chains between icosahedra. Additionally, the Schottky barrier study indicates that a clean surface was necessary before deposition of an ohmic contact and from the metals studied. Such studies are important to applications for high temperature thermoelectric converters, high-efficiency direct-conversion solid-state neutron detectors and microelectronicseng
dc.description.tableofcontentsAbstract -- List of illustrations -- List of tables -- List of equations -- Acknowledgements -- Introduction and background -- Experimental theory and methods -- Understanding the chemical and electronic structure of a-BXC:HY thin-films using photoemission -- The effects of thermal treatment on amorphous hydrogenated boron carbide: a study of the bulk chemical and electronic structure -- Metal-To-Boron carbide interface: implications for Schottky Barrier Heights -- Summary and future work -- Appendixeng
dc.format.extentxxix, 228 pageseng
dc.identifier.urihttp://hdl.handle.net/10355/41502eng
dc.subject.lcshCarboneng
dc.subject.lcshAmorphous substanceseng
dc.subject.lcshboroneng
dc.subject.otherDissertation -- University of Missouri--Kansas City -- Physicseng
dc.subject.otherDissertation -- University of Missouri--Kansas City -- Chemistryeng
dc.titleThe Bulk and Interfacial Electronic and Chemical Structure of Amorphous Hydrogenated Boron Carbideeng
dc.typeThesiseng
thesis.degree.disciplinePhysics (UMKC)eng
thesis.degree.disciplineChemistry (UMKC)eng
thesis.degree.grantorUniversity of Missouri--Kansas Cityeng
thesis.degree.levelDoctoraleng
thesis.degree.namePh. D.eng


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