X-Ray Photoelectron Spectroscopy


Soft x-rays are used to probe the outer layers of the sample. Emitted photoelectrons are being analyzed by energy in the analyzer and plotted as a function of binding energy. Resulting spectrum is obtained from the sample layers within ~3 nm in depth thus giving great surface sensitivity.


  • Thin films and semiconductors
    • Surface segregation
    • Surface sensitive analysis
    • Parallel imaging of chemical state (Si vs SiO2)
  • Surface Oxides and Glasses
    • Layering (Stratification)
    • Depth information
    • Polymers and Organics
    • Functional groups according to the chemical shift
    • Bonding information, presence of catalysts traces, etc.
  • Metals
    • Oxidation states
    • Metal oxide to metal layers
  • Catalysis
    • Characterization of surface components on catalyst
    • Characterization catalysis products and intermediates
  • Biological
    • Elemental information from thin layers (sections)
    • Presence of trace elements, mineral, etc.
  • Depth Profiling Using Focused Ion Beam
  • Non-destructive depth profiling using resolved XPS
  • Other applications include fast parallel elemental, Auger and secondary election imaging, Auger spectroscopy, and UPS spectroscopy.

Data Processing

The University of Iowa purchased a site license for data processing software, CasaXPS by Neal Fairley. You can find it at www.casaxps.com.

The latest release is 2.3.12 and can be downloaded from the web-page: http://www.casaxps.com/release/release2312_/. The zip file contains the excutable together with default library (based on Scofield cross-sections), HTML help maual and configuration files (~25Mb). Please note, that Kratos relative sensitivity factor library is used in CMRF room 88 by our staff. You will have to replace standard Scofield cross-section library by the Kratos one, after you download CasaXPS. The Kratos library in CasaXPS format plus other utilities can be found on www.casaxps.com/kratos. Download the file, unzip it and paste on the top of CasaXPS directory. When asked to overwrite the existing files, say yes.

A good place is www.casaxps.com/help_manual/manual_updates as Neal Fairley places a development version on this page and also adds newly created manual entries, mostly in PDF format.

After downloading the software, you will have to register it in order to have the option of saving files. To access the username and password for CasaXPS, please contact Jonas Baltrusaitis.

To register the software with U of I license, start Casaxps.exe, go to Help, About CasaXPS and enter User Name and License.


Below is the list of publications submitted and published that contain data acquired using the University of Iowa Kratos Axis Ultra XPS System:

    1. Dutta, Samrat; Perring, Mathew; Barrett, Stephen; Mitchell, Michael; Kenis, Paul J.A.; Bowden, Ned B.. Cross Metathesis on Olefin-Terminated Monolayers on Si(11) Using the Grubbs' Catalyst. Langmuir (2006), 22(5), 2146-2155.

    2. Kiss Peter J; Knisz Judit; Zhang Yuzhou; Baltrusaitis Jonas; Sigmund Curt D; Thalmann Ruediger; Smith Richard J H; Verpy Elisabeth; Banfi Botond Inactivation of NADPH oxidase organizer 1 results in severe Imbalance. Current biology : CB (2006), 16(2), 208-13

Authors publishing CMRF XPS data should acknowledge the Central Microscopy Research Facility and the NSF grant CHE 0320387 that allowed purchasing the instrument.

To obtain the publishable spectra in the ASCII, jpeg or any other format, as well as experimental part write-up, quantification tables, parallel images etc., please contact the CMRF staff person that worked on the data acquisition.