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MAPEX Core Facility

Instrument Database

Allgemeine Informationen

  • Untersuchungsgebiete
    3D Materials Analytics
  • Techniken
    Atom Probe Tomography
  • Hersteller
    Cameca
  • Herstellungsjahr
    2021
  • Gemessene Größe
    Chemical composition, with no lower or upper limits of elemental mass, within samples with a typical size of 100 x 100 x 500 nm³
  • Hauptanwendung
    3D compositional mapping with a sub-nanometer resolution and high sensitivity (appm)
  • Korrelierter Arbeitsablauf verfügbar
    Ja

Spezifikationen des Geräts

  • Technische Aspkete

    Our LEAP 5000 XR atom probe tomography equipment enables the quantitative analysis of local chemical composition at the sub-nanometer scale with a sensitivity in the range of appm. All elements can be detected with the same efficiency, including light elements such as hydrogen, carbon or lithium. The achieved mass resolution is sufficient to distinguish each isotope of each of the detected elements. Our APT is equipped with a reflectron that bends the ion trajectories, thereby offering the possibility to extend the time of flight of the ions and improve the relative precision of the measurement and the mass resolution.

    The method: APT is underpinned by the field evaporation of surface atoms of a needle-shaped specimen with a radius of curvature of approximately 100 nm. It is therefore a destructive technique. Each atom is desorbed and ionized one by one using high voltage or laser pulses, in addition to the direct current (DC) voltage. Then , the elemental nature of each detected ion is identified thanks to a time-of-flight mass spectrometer , and coupled to its own impact position , allowing us to generate a 3D point cloud that reveals the solute distribution in 3D.

    Sample type and preparation: APT can be used to characterize all conductive and semi-conductive samples. In the latter, a pulsed-laser beam is focused towards the specimen apex. In our lab, we analyze steels, aluminum alloys for aerospatial applications, cupper alloys for microelectronics applications, and more.

    Sample size and geometry: Samples needs to be in the shape of a needle, with a sharp apex (radius of curvature below 100 nm). The samples can be prepared using electropolishing or by focused ion beam (FIB). The size of the analyzed volume is typically 100 x 100 x 500 nm3.

  • Korrelierter Arbeitsablauf
    Atom probe tomography can be combined with transmission electron microscopy (TEM). The correlated workflow is under development with the Institute for Solid State Physics (Institut für Festkörperphysik, FB1) in the University of Bremen.
  • Weitere Untersuchungsmöglichkeiten
    APT is ideally suited to complement electron-based or X-ray-based microscopies and spectroscopies. A cryogenic ultra-high-vacuum transport module (VCTM) is also installed to transfer samples from the SEM-FIB to the APT in a protected environment, in order to avoid any contamination from the ambiant air and/or increase in temperature of the specimen.

Kontaktperson

Gerätestandort

  • Gebäude
    IW 1/2
  • Raum
    0090
  • Fachbereich
    --
  • Institut (Außeruniversitär)
    IWT
Aktualisiert von: MAPEX
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