Specific Process Knowledge/Characterization/XPS/NexsaOverview: Difference between revisions
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| [[media:Prusa-2015-Highly-sensitive-detection-of-surfa.pdf | Highly Sensitive Detection of Surface and Intercalated Impurities in Graphene by LEIS]]||Publication||S Prusa||[http://apps.webofknowledge.com.proxy.findit.dtu.dk/CitedFullRecord.do?product=WOS&colName=WOS&SID=F6P8vdNQigRKywglhCq&search_mode=CitedFullRecord&isickref=WOS:000361087000013 link]||||||X||||||||graphene||<span title="Low-energy ion scattering (LEIS) is known for its extreme surface sensitivity, as it yields a quantitative analysis of the outermost surface as well as highly resolved in-depth information for ultrathin surface layers. Hence, it could have been generally considered to be a suitable technique for the analysis of graphene samples. However, due to the low scattering cross section for light elements such as carbon, LEIS has not become a common technique for the characterization of graphene. In the present study we use a high-sensitivity LEIS instrument with parallel energy analysis for the characterization of CVD graphene transferred to thermal silica/silicon substrates. Thanks to its high sensitivity and the exceptional depth resolution typical of LEIS, the graphene layer closure was verified, and different kinds of contaminants were detected, quantified, and localized within the graphene structure. Utilizing the extraordinarily strong neutralization of helium by carbon atoms in graphene, LEIS experiments performed at several primary ion energies permit us to distinguish carbon in graphene from that in nongraphitic forms (e.g., the remains of a resist). Furthermore, metal impurities such as Fe, Sn, and Na located at the graphene−silica interface (intercalated) are detected, and the coverages of Fe and Sn are determined. Hence, high-resolution LEIS is capable of both checking the purity of graphene surfaces and detecting impurities incorporated into graphene layers or their interfaces. Thus, it is a suitable method for monitoring the quality of the whole fabrication process of graphene, including its transfer on various substrates."> Abstract</span> | | [[media:Prusa-2015-Highly-sensitive-detection-of-surfa.pdf | Highly Sensitive Detection of Surface and Intercalated Impurities in Graphene by LEIS]]||Publication||S Prusa||[http://apps.webofknowledge.com.proxy.findit.dtu.dk/CitedFullRecord.do?product=WOS&colName=WOS&SID=F6P8vdNQigRKywglhCq&search_mode=CitedFullRecord&isickref=WOS:000361087000013 link]||||||X||||||||graphene||<span title="Low-energy ion scattering (LEIS) is known for its extreme surface sensitivity, as it yields a quantitative analysis of the outermost surface as well as highly resolved in-depth information for ultrathin surface layers. Hence, it could have been generally considered to be a suitable technique for the analysis of graphene samples. However, due to the low scattering cross section for light elements such as carbon, LEIS has not become a common technique for the characterization of graphene. In the present study we use a high-sensitivity LEIS instrument with parallel energy analysis for the characterization of CVD graphene transferred to thermal silica/silicon substrates. Thanks to its high sensitivity and the exceptional depth resolution typical of LEIS, the graphene layer closure was verified, and different kinds of contaminants were detected, quantified, and localized within the graphene structure. Utilizing the extraordinarily strong neutralization of helium by carbon atoms in graphene, LEIS experiments performed at several primary ion energies permit us to distinguish carbon in graphene from that in nongraphitic forms (e.g., the remains of a resist). Furthermore, metal impurities such as Fe, Sn, and Na located at the graphene−silica interface (intercalated) are detected, and the coverages of Fe and Sn are determined. Hence, high-resolution LEIS is capable of both checking the purity of graphene surfaces and detecting impurities incorporated into graphene layers or their interfaces. Thus, it is a suitable method for monitoring the quality of the whole fabrication process of graphene, including its transfer on various substrates."> Abstract</span> | ||
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| [[media:Shin_et_al-2012-Surface_and_Interface_Analysis.pdf | Reflection electron energy loss spectroscopy for ultrathin gate oxide materials]]||Publication||H C Shin||[http://apps.webofknowledge.com.proxy.findit.dtu.dk/CitedFullRecord.do?product=WOS&colName=WOS&SID=F6P8vdNQigRKywglhCq&search_mode=CitedFullRecord&isickref=WOS:000304348200002]||X||||||X||||Valence band||HfZrO4,||<span title="The band alignment of HfZrO4 gate oxide thin films on Si (100) deposited by the atomic layer deposition method has been investigated using reflection electron energy loss spectroscopy and XPS. The band gap of HfZrO4 gate oxide thin film is 5.40 +/-0.05 eV. The valence band offset (ΔEv) and the conduction band offset (ΔEc) are 2.50+/-0.05 eV and 1.78+/-0.05 eV, respectively. These values satisfy the minimum requirement for the hole and electron barrier heights of larger than 1 eV for device applications. We have demonstrated that the quantitative analysis of reflection electron energy loss spectroscopy spectra obtained from HfZrO4 thin films provides us a straightforward way to determine the optical properties and the inelastic mean free path of ultrathin gate oxide materials."> Abstract</span> | | [[media:Shin_et_al-2012-Surface_and_Interface_Analysis.pdf | Reflection electron energy loss spectroscopy for ultrathin gate oxide materials]]||Publication||H C Shin||[http://apps.webofknowledge.com.proxy.findit.dtu.dk/CitedFullRecord.do?product=WOS&colName=WOS&SID=F6P8vdNQigRKywglhCq&search_mode=CitedFullRecord&isickref=WOS:000304348200002 link]||X||||||X||||Valence band||HfZrO4,||<span title="The band alignment of HfZrO4 gate oxide thin films on Si (100) deposited by the atomic layer deposition method has been investigated using reflection electron energy loss spectroscopy and XPS. The band gap of HfZrO4 gate oxide thin film is 5.40 +/-0.05 eV. The valence band offset (ΔEv) and the conduction band offset (ΔEc) are 2.50+/-0.05 eV and 1.78+/-0.05 eV, respectively. These values satisfy the minimum requirement for the hole and electron barrier heights of larger than 1 eV for device applications. We have demonstrated that the quantitative analysis of reflection electron energy loss spectroscopy spectra obtained from HfZrO4 thin films provides us a straightforward way to determine the optical properties and the inelastic mean free path of ultrathin gate oxide materials."> Abstract</span> | ||
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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||Oxygen on metal surfaces||<span title="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||Oxygen on metal surfaces||<span title="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> | ||