Office of Science

Mass Spectrometer: Time of Flight Secondary Ion (ToF SIMS) - 2007

Quick Specs

  • Ultrahigh vacuum
  • C60 ion gun
  • Liquid metal ion gun with Bin+ cluster sources
  • Cs+/O2+ sputter ion gun
  • 0-10,000 amu mass range
  • Mass resolution >10000
  • ~100 nm lateral resolution
  • ~ 1 nm depth resolution

This ultrahigh vacuum surface analytical system is designed to examine surface structure, composition, and chemical state by means of secondary ion detection during ion sputtering. The instrument will be furnished with a C60 ion gun, a liquid metal ion gun with Bin+ sources, and a Cs+/O2+ sputter ion gun with emission current stabilizers. The capabilities include surface spectroscopy with high sensitivity and mass resolution, surface imaging with high lateral resolution, depth profiling with high depth resolution, and 3-D analysis. The ability to provide cluster ions, such as Bin+ and C60+, will enable EMSL users to obtain substantial improvements in detection yields, especially in biological materials. The C60 ion gun can provide ultimate high mass sensitivity, superior imaging, and a powerful organic sputter depth profiling capability with C60+ or C602+ ions.

This new instrumentation provides the user the flexibility to image with minimal shadowing on samples with high surface topography as well as the highest commercially available mass resolution performance. Low primary energy and low ion dose densities provide surface analysis without significantly altering of surface. The system is equipped with an introduction chamber and a glove box for sample transfer under controlled environment. In addition, EMSL staff are in the process of building a side chamber with limited processing capabilities and cryo-sample manipulation capability so that biological samples can be processed in the side chamber before the samples are transferred to the main system for SIMS analysis. This instrument will significantly improve EMSL's ability in areas such as microbial forensics, organic analysis, and biological imaging.

Physical Operating CriteriaPrimary Performance Parameters
Operating Vacuum Conditions≤ 2x10-10 Torr
Ion Species, Energy Range
  • 1-10 KeV C60+
  • 1-20 KeV C602+
  • 10-25 KeV Bi+, Bi3+, Bi5+
  • 0.5 − 2KeV Cs+ and O2+
SpectrometerToF mass spectrometer, 0-10,000 amu mass range
  • Surface spectroscopy (high sensitivity with mass resolution >10,000)
  • Surface imaging (lateral resolution ~ 100 nm)
  • Depth profiling (depth resolution ~ 1 nm) and 3D analysis
  • Isotope quantification
  • -150°C to 600°C in-situ cooling/heating
Specimen Exchange Capability
  • Sample introduction system
  • Future incorporation of EMSL transfer technology
  • Anerobic sample transfer
Data Acquisition/AnalysisPC based Computer workstation interface
  1. In situ SEM and ToF-SIMS analysis of IgG conjugated gold nanoparticles at aqueous surfaces.
  2. Assigning Oxidation States to Organic Compounds via Predictions from X-ray Photoelectron Spectroscopy: A Discussion of Approaches and Recommended Improvements.
  3. Long-term Kinetics of Uranyl Desorption from Sediments Under Advective Conditions.
  4. A Segmented, Enriched N-type Germanium Detector for Neutrinoless Double Beta-Decay Experiments.
  5. Cold Crucible Induction Melter Studies for Making Glass Ceramic Waste Forms: A Feasibility Assessment.
  1. Interpretation will crack the microbial language code (Microbial communication)
  2. Iron-bearing minerals in sediments naturally reduce contaminant levels (Lack of iron)
  3. Examining the core components of Arctic clouds to clear up their influence on climate (Forecast calls for better models)
  4. Predictive models of environmental reaction kinetics made more accurate, scalable (Scaled up)
  5. Scientists gain first quantitative insights into electron transfer from minerals to microbes (Tunable transfer)
Zhu, Zihua | , 509-371-6240