Instrument: VG Scientific SIMSLAB IV Secondary Ion Mass Spectrometer/Sputtered Neutral Mass Spectrometer


Surface and Thin Film Analysis


136 Eberly Hall



The VG SIMSLAB IV is a secondary ion mass spectrometer (SIMS) used for the high sensitivity analysis of surfaces and thin films. SIMS provides enhanced sensitivity and signal to noise ratios relative to electron spectroscopy techniques such as XPS and AES while having a higher surface sensitivity, the later controlled by the energy of the primary ion beam. Typical sensitivities are ppm or better. All elements including H and He are detectable and, as molecular ions are generated, additional compositional information is available.

Key features of this instrument include:

  • High resolution single quadrupole mass analyzer with range of 1-800 amu
  • Better than unit mass resolution over entire mass range, peak width less than 5% of peak height
  • Flood gun for charge compensation of non-conductive or insulating samples
  • Scintillation and PMT detector for scanning SIMS and ion induced SEM imaging
  • Choice of four ion guns:
    • MIG100 liquid metal ion gun (Ga+), 500 nm spot size, 1-10 keV beam
    • AG61 Ar+ ion gun, 50 um spot size, 0.1-5 keV beam
    • DP50A duoplasmatron O2 ion gun, 5 um spot size, 2-10 keV beam
    • FAB (fast atom bombardment) source
  • A post sputter ionizer is available for ionization of sputtered neutral species (SNMS)
  • The instrument may be run in either static or dynamic modes

Typical applications of the instrument include:

  • High resolution depth profiling (especially important in cases where ion bombardment of surfaces leads to atomic mixing)
  • Ion imaging/microscopy
  • Isotope detection
  • High sensitivity detection of surface bound species