Versailles Project on Advanced Materials and Standards interlaboratory study on intensity calibration for x-ray photoelectron spectroscopy instruments using low-density polyethylene

We report the results of a Versailles Project on Advanced Materials and Standards interlaboratory study on the intensity scale calibration of x-ray photoelectron spectrometers using low-density polyethylene (LDPE) as an alternative material to gold, silver, and copper. An improved set of LDPE reference spectra, corrected for different instrument geometries using a quartz-monochromated Al Kα x-ray source, was developed using data provided by participants in this study. Using these new reference spectra, a transmission function was calculated for each dataset that participants provided. When compared to a similar calibration procedure using the NPL reference spectra for gold, the LDPE intensity calibration method achieves an absolute offset of ∼3.0% and a systematic deviation of ±6.5% on average across all participants. For spectra recorded at high pass energies (≥90 eV), values of absolute offset and systematic deviation are ∼5.8% and ±5.7%, respectively, whereas for spectra collected at lower pass energies (<90 eV), values of absolute offset and systematic deviation are ∼4.9% and ±8.8%, respectively; low pass energy spectra perform worse than the global average, in terms of systematic deviations, due to diminished count rates and signal-to-noise ratio. Differences in absolute offset are attributed to the surface roughness of the LDPE induced by sample preparation. We further assess the usability of LDPE as a secondary reference material and comment on its performance in the presence of issues such as variable dark noise, x-ray warm up times, inaccuracy at low count rates, and underlying spectrometer problems. In response to participant feedback and the results of the study, we provide an updated LDPE intensity calibration protocol to address the issues highlighted in the interlaboratory study. We also comment on the lack of implementation of a consistent and traceable intensity calibration method across the community of x-ray photoelectron spectroscopy (XPS) users and, therefore, propose a route to achieving this with the assistance of instrument manufacturers, metrology laboratories, and experts leading to an international standard for XPS intensity scale calibration

Preparation and characterization of nanostructured titanium(IV) oxide layers on different substrates

Celem niniejszej pracy było opracowanie i zoptymalizowanie metod wytwarzania samoorganizujących się struktur tlenku tytanu na podłożu metalicznym i półprzewodnikowym, modyfikacja ich struktury pod kątem krystaliczności oraz charakterystyka podstawowych własności otrzymanych warstw. Do przygotowania podłoża metalicznego stosowano obróbkę mechaniczną oraz chemiczną. Warstwę Ti na podłożu półprzewodnikowym otrzymano przy pomocy fizycznego osadzania ze źródła wzbudzanego wiązką elektronów. Głównym narzędziem do wytworzenia samoorganizujących się nanorurek tlenku tytanu(IV) był proces elektrochemicznego utleniania, czyli anodyzacji. Otrzymane warstwy poddawano dalszej obróbce celem usunięcia zanieczyszczeń i uporządkowania ich struktury. Charakterystyka otrzymanych powłok tlenkowych polegała na określeniu ich morfologii przy użyciu skaningowego mikroskopu elektronowego, oraz zbadaniu ich składu i krystaliczności za pomocą spektroskopii ramanowskiej, spektroskopii dyspersji energii i dyfraktometrii promieniowania X. Badania pozwoliły na otrzymanie nanostrukturalnego tlenku tytanu w formie rurek o kontrolowanej średnicy. Opracowano też metody obróbki wytworzonych warstw tlenkowych pozwalające uzyskać materiał krystaliczny o dużej czystości chemicznej.The aim of this work was to develop and optimize the production method of self-organized titanium oxide structures on metal and semiconductor surface, modify their crystallinity and characterize basic properties of obtained coating. Metal surface was prepared by chemical and physical treatment. Ti layers were deposited on semiconductive surface by electron beam physical vapor deposition. Self-organized titania nanotubes were obtaing using electrochemical oxidation known as anodization. Obtained coatings were further treated to remove pollution and order the structure. Oxide layers were analyzed using scanning electron microscope, Raman spectroscopy, energy-dispersive spectroscopy and X-ray diffraction. As a result, titanium oxide nanotubes with adjustable diameter were obtained and methods to achieve crystalline and chemically pure coatings were developed

Structural and magnetic properties of FePd alloys on nanoporous oxide substrates

W niniejszej pracy przedstawiono badania nad zmianami morfologicznymi, strukturalnymi i magnetycznymi stopu FePd utworzonego z układu wielowarstwowego. Wielowarstwy były osadzane na podłożach nanoporowatych wykonanych z anodyzowanego tlenku glinu i anodyzowanego tlenku tytanu o różnej charakterystyce powierzchni. Zbadano tendencje zmian właściwości układów pod wpływem wygrzewania w temperaturach 450°C, 530°C i 600°C. Zmiany właściwości próbek na poszczególnych podłożach w funkcji temperatury wygrzewania scharakteryzowano przy pomocy mikroskopii elektronowej, dyfraktometrii i reflektometrii rentgenowskiej oraz magnetometrii. Dzięki wykorzystaniu podłoży nanostrukturyzowanych wytworzono warstwy twardej magnetycznie fazy FePd o strukturze L10. Koercja próbek sięgała od 1000 do 1600 Oe i była wyższa niż w przypadku stopu na płaskim podłożu krzemowym.In present work studies on changes of morphology, structure and magnetic properties of FePd alloy formed from a multilayer system were performed. Multilayers were deposited on nanoporous aluminium oxide and nanoporous titanium oxide substrates with different surface characteristics. The tendencies of changes in the system properties under influence of annealing at 450°C, 530°C and 600°C were investigated. Changes of sample properties on each substrate in function of the annealing temperature were characterised using electron microscopy, X-ray diffraction and reflectivity, and magnetometry. Using nanoporous substrates a hard magnetic FePd phase with L10 structure was obtained. The coercivity of magnetic layer was between 1000 and 1600 Oe, which was higher than the alloy on the flat silicon substrate

The influence of nanoporous anodic titanium oxide substrates on the growth of the crystalline hydroxyapatite coatings

In this study we investigate the effect of the nanoporous anodic titanium oxide substrate on the morphology and uniformity of hydrothermally precipitated hydroxyapatite coatings. Nanotubular TiO2 substrates were synthesized on a titanium plate by anodic oxidation and subsequently annealed at 500 °C or 600 °C to create the crystalline anatase and/or rutile forms of TiO2. The substrates were further used for HAp growth under hydrothermal conditions. The samples were then characterized with the XRD, Raman and SEM techniques. The results show that hydrothermal synthesis leads to formation of needle-like coating layer of HAp particles. The diameter and length of HAp crystals decrease with increasing annealing temperature of TiO2 nanotubular arrays. Furthermore, we demonstrate that nanostructured surface of titanium oxide has beneficial influence on the HAp nucleation and coverage

ERRATUM: “Versailles project on advanced materials and standards interlaboratory study on intensity calibration for x-ray photoelectron spectroscopy instruments using low-density polyethylene” [J. Vac. Sci. Technol. A 38, 063208 (2020)]

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ERRATUM: “Versailles project on advanced materials and standards interlaboratory study on intensity calibration for x-ray photoelectron spectroscopy instruments using low-density polyethylene” [J. Vac. Sci. Technol. A 38, 063208 (2020)]

From Crossref journal articles via Jisc Publications RouterHistory: epub 2021-01-25, issued 2021-01-25, ppub 2021-03-01Publication status: Publishe