Specific Process Knowledge/Characterization/XPS/NexsaOverview: Difference between revisions
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| [[media:Steinberger-2017-Oxygen-accumulation-on-metal-surfac.pdf | Oxygen accumulation on metal surfaces investigated by XPS, AES and LEIS, an issue for sputter depth profiling under UHV conditions]]||Publication||R Steinberger||[http://apps.webofknowledge.com.proxy.findit.dtu.dk/CitedFullRecord.do?product=WOS&colName=WOS&SID=F6P8vdNQigRKywglhCq&search_mode=CitedFullRecord&isickref=WOS:000401391900023 link]||X||||X||||||AES, ARXPS, sputter profiles||<span title="Oxygen on metal surfaces||Depth profiling using surface sensitive analysis methods in combination with sputter ion etching is a common procedure for thorough material investigations, where clean surfaces free of any contaminationare essential. Hence, surface analytic studies are mostly performed under ultra-high vacuum (UHV) conditions, but the cleanness of such UHV environments is usually overrated. Consequently, the current study highlights the in principle known impact of the residual gas on metal surfaces (Fe, Mg, Al, Cr and Zn) for various surface analytics methods, like X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and low-energy ion scattering (LEIS). The investigations with modern, stateof-the-art equipment showed different behaviors for the metal surfaces in UHV during acquisition: (i) no impact for Zn, even after long time, (ii) solely adsorption of oxygen for Fe, slight and slow changes for Cr and (iii) adsorption accompanied by oxide formation for Al and Mg. The efficiency of different counter measures was tested and the acquired knowledge was finally used for ZnMgAl coated steel to obtain accurate depth profiles, which exhibited before serious artifacts when data acquisition was performed in an inconsiderate way."> Abstract</span> | | [[media:Steinberger-2017-Oxygen-accumulation-on-metal-surfac.pdf | Oxygen accumulation on metal surfaces investigated by XPS, AES and LEIS, an issue for sputter depth profiling under UHV conditions]]||Publication||R Steinberger||[http://apps.webofknowledge.com.proxy.findit.dtu.dk/CitedFullRecord.do?product=WOS&colName=WOS&SID=F6P8vdNQigRKywglhCq&search_mode=CitedFullRecord&isickref=WOS:000401391900023 link]||X||||X||||||AES, ARXPS, sputter profiles||<span title="Oxygen on metal surfaces||Depth profiling using surface sensitive analysis methods in combination with sputter ion etching is a common procedure for thorough material investigations, where clean surfaces free of any contaminationare essential. Hence, surface analytic studies are mostly performed under ultra-high vacuum (UHV) conditions, but the cleanness of such UHV environments is usually overrated. Consequently, the current study highlights the in principle known impact of the residual gas on metal surfaces (Fe, Mg, Al, Cr and Zn) for various surface analytics methods, like X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and low-energy ion scattering (LEIS). The investigations with modern, stateof-the-art equipment showed different behaviors for the metal surfaces in UHV during acquisition: (i) no impact for Zn, even after long time, (ii) solely adsorption of oxygen for Fe, slight and slow changes for Cr and (iii) adsorption accompanied by oxide formation for Al and Mg. The efficiency of different counter measures was tested and the acquired knowledge was finally used for ZnMgAl coated steel to obtain accurate depth profiles, which exhibited before serious artifacts when data acquisition was performed in an inconsiderate way."> Abstract</span> | ||
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| [[media:Symianakis-2015-Electrochemical-characterization-an.pdf | Electrochemical Characterization and Quantified Surface Termination Obtained by Low Energy Ion Scattering and X-ray Photoelectron Spectroscopy of Orthorhombic and Rhombohedral LaMnO3 Powders]]||Publication||E Symianakis||||X||||X||||||XRD||Catalysts, LaMnO3||<span title="LaMnO3 powder synthesized by glycine combustion synthesis with the rhombohedral and orthorhombic structures has been characterized by the combination of low energy ion scattering (LEIS) and X-ray photoelectron spectroscopy (XPS), while the electrocatalytic activity for the oxygen reduction reaction is measured with the rotating disk electrode (RDE) method. Quantification of the surface terminations obtained by LEIS suggests that the orthorhombic LaMnO3 crystallites are near thermodynamic equilibrium as surface atomic ratios compare well with those of equilibrium morphologies computed by a Wulff construction based on computed surface energies. Both rhombohedral and orthorhombic structures present the same La/Mn atomic ratio on the surface. Electrochemical activity of the two structures is found to be the same within the error bar of our measurements. This result is in disagreement with results previously reported on the activity of the two structures obtained by the coprecipitation method [Suntivich et al. Nat. Chem. 2011, 3 (7), 546], and it indicates that the preparation method and the resulting surface termination might play a crucial role for the activity of perovskite catalysts."> Abstract</span> | | [[media:Symianakis-2015-Electrochemical-characterization-an.pdf | Electrochemical Characterization and Quantified Surface Termination Obtained by Low Energy Ion Scattering and X-ray Photoelectron Spectroscopy of Orthorhombic and Rhombohedral LaMnO3 Powders]]||Publication||E Symianakis||[http://apps.webofknowledge.com.proxy.findit.dtu.dk/full_record.do?product=WOS&search_mode=CitingArticles&qid=283&SID=F6P8vdNQigRKywglhCq&page=1&doc=3 link]||X||||X||||||XRD||Catalysts, LaMnO3||<span title="LaMnO3 powder synthesized by glycine combustion synthesis with the rhombohedral and orthorhombic structures has been characterized by the combination of low energy ion scattering (LEIS) and X-ray photoelectron spectroscopy (XPS), while the electrocatalytic activity for the oxygen reduction reaction is measured with the rotating disk electrode (RDE) method. Quantification of the surface terminations obtained by LEIS suggests that the orthorhombic LaMnO3 crystallites are near thermodynamic equilibrium as surface atomic ratios compare well with those of equilibrium morphologies computed by a Wulff construction based on computed surface energies. Both rhombohedral and orthorhombic structures present the same La/Mn atomic ratio on the surface. Electrochemical activity of the two structures is found to be the same within the error bar of our measurements. This result is in disagreement with results previously reported on the activity of the two structures obtained by the coprecipitation method [Suntivich et al. Nat. Chem. 2011, 3 (7), 546], and it indicates that the preparation method and the resulting surface termination might play a crucial role for the activity of perovskite catalysts."> Abstract</span> | ||
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| [[media:Wiesing-2016-The-thermal-oxidation-of-tialn-high.pdf | The Thermal Oxidation of TiAlN High Power Pulsed Magnetron Sputtering Hard Coatings as Revealed by Combined Ion and Electron Spectroscopy]]||Publication||M Wiesing||[https://apps-webofknowledge-com.proxy.findit.dtu.dk/CitedFullRecord.do?product=WOS&colName=WOS&SID=F6P8vdNQigRKywglhCq&search_mode=CitedFullRecord&isickref=WOS:000399031000003 link]||X||X||X||||||Ar sputtering||TiAlN||<span title="The thermal oxidation of TiAlN hard coatings deposited by High Power Pulsed Magnetron Sputtering (HPPMS) is investigated at room temperature and 800 K at oxygen pressures ranging from 10−6 to 10−2 Pa by means of in situ X-ray and Ultraviolet Photoelectron Spectroscopy as well as Low Energy Ion Scattering. The spectra reveal that oxygen binds selectively to titanium during the initial chemisorption step and simultaneously some oxygen is dissolved into subsurface layers, which stay metallic. Enhanced oxidation results into continuous formation of a multilayered oxide film including oxynitride TiAl(O,N) as a metastable reaction product buried below an oxidic top layer. This top layer is either composed of mixed TiAlO after oxidation at 800 K or of segregated TiO2 and Al2O3 when oxidizing at 293 K. Additionally, evaluation of UV-valence bands reveals nitrogen doping of the surface oxide films. The results are of high relevance for tailoring of the surface characteristics of TiAlN after deposition, for the design of TiAlN multilayers and for an improved understanding of the interactions of gas particles with these coatings. "> Abstract</span> | | [[media:Wiesing-2016-The-thermal-oxidation-of-tialn-high.pdf | The Thermal Oxidation of TiAlN High Power Pulsed Magnetron Sputtering Hard Coatings as Revealed by Combined Ion and Electron Spectroscopy]]||Publication||M Wiesing||[https://apps-webofknowledge-com.proxy.findit.dtu.dk/CitedFullRecord.do?product=WOS&colName=WOS&SID=F6P8vdNQigRKywglhCq&search_mode=CitedFullRecord&isickref=WOS:000399031000003 link]||X||X||X||||||Ar sputtering||TiAlN||<span title="The thermal oxidation of TiAlN hard coatings deposited by High Power Pulsed Magnetron Sputtering (HPPMS) is investigated at room temperature and 800 K at oxygen pressures ranging from 10−6 to 10−2 Pa by means of in situ X-ray and Ultraviolet Photoelectron Spectroscopy as well as Low Energy Ion Scattering. The spectra reveal that oxygen binds selectively to titanium during the initial chemisorption step and simultaneously some oxygen is dissolved into subsurface layers, which stay metallic. Enhanced oxidation results into continuous formation of a multilayered oxide film including oxynitride TiAl(O,N) as a metastable reaction product buried below an oxidic top layer. This top layer is either composed of mixed TiAlO after oxidation at 800 K or of segregated TiO2 and Al2O3 when oxidizing at 293 K. Additionally, evaluation of UV-valence bands reveals nitrogen doping of the surface oxide films. The results are of high relevance for tailoring of the surface characteristics of TiAlN after deposition, for the design of TiAlN multilayers and for an improved understanding of the interactions of gas particles with these coatings. "> Abstract</span> | ||