Surface Analytics / Instrumentation

The surface analytics facility provides state-of-the-art instrumentations and expertise in the fields optical and electron spectroscopies, as well as nanoscale imaging and force spectroscopy. The instrumentation is mostly dedicated to the analysis of powders, thin films and bulk materials. It comprises:

  • Photoelectron spectroscopy – XPS, ARXPS, UPS: quantitative measurement of surface atomic composition and chemical state analysis, through electronic properties.
  • Auger electron spectroscopy – AES: nanoscale imaging and spectroscopy of surface composition.
  • Raman spectroscopy & microscopy: molecular determination by assessing vibrational fingerprints
  • Atomic force microscopy & spectroscopy AFM: topography and interaction forces at the nanoscale, with full capabilities for quantitative nanomechanical measurements, including Young modulus, indentation, and adhesion properties. 
  • Kelvin probe microscopy – KPFM: electrical properties at the nanoscale, allowing the determination of the material’s work function, electric and magnetic properties.

Most of these instruments are in open-access after a successful training.

Techniques from the family of Scanning Probe Microscopy such SNOM for the nanoscale imaging and spectroscopy of photoluminescence and fluorescence, STM to assess the electronic density of states at the nanoscale, and spatially resolved Raman spectroscopy TERS are also available either as a service or through the organisation of collaborations.

For measurements requests be it for academia or industry please contact Mounir Mensi.

Instruments:

XPS, ARXPS, UPS, AES: Kratos Axis Supra

  • Monochromated Al Ka X-ray source
  • Monochromated Ag La X-ray source
  • He(I) and He(II) UV source for UPS
  • Ar+ sputter gun
  • FEG electron gun for AES and Auger microscopy, spot size ~100nm.
  • Heat-cool sample stage: LN2 – 600°C
  • Inert gas transfer vessel for air sensitive samples

NAP-XPS: SPECS

  • Monochromated Al Ka X-ray source
  • Non-monochromated Mg Ka X-ray source
  • NAP cell pressure up to 10 mbar
  • He(I) and He(II) UV source
  • Sample preparation chamber (sputtering, ESD, heat-cool)
  • Connected under vacuum to an STM (SPECS/Nanonis, Colibri sensor)

Confocal Raman microscope: Renishaw inVia

  • 457nm, 532nm and 632nm lasers (785nm to be installed)
  • Confocal mode: signal discrimination based spatial position
  • Time series: monitor how your sample is altering with time
  • Automated sample stage for surface/volume mapping
  • Molecular and elements database and spectral recognition
  • Heat-cool gas cell available in a collaboration scheme
  • Compatible with EPFL’s electronic lab book (ELN), which now includes a simulation of molecular vibrational levels in ELN-beta.

AFM: Bruker multimode 8-HR / QNM

  • State of the art, high resolution AFM
  • Quantitative nanomechanical properties
  • Kelvin probe microscopy (work function determination)
  • Large selection of (calibrated) probes for different application
  • Largely automated

STM: SPECS/Nanonics (vacuum only)

  • Colibri sensor
  • Feedback modes: STM, AM-AFM, FM-AFM
  • Atomic resolution in both AFM and STM configurations
  • Heat-cold sample stage
  • Connected under vacuum to a NAP-XPS