XPS for Beginners

Data Analysis 2

Open the dataset by downloading from the link above and opening in CasaXPS.

  1. Calibrate the sample to C 1s @ 248.8 eV
  2. Calibrate the samples to Si 2p @ 103.5 eV
  3. Calibrate these samples to either C 1s or Si 2p (or both!)

To calibrate to adventitious carbon, first open the processing window by clicking the icon (1) or pressing F8.

Next, open the calibration tab (2) and enter 284.8 into the ‘True’ energy field (3). Click on the peak maxima of the C 1s peak to update the ‘Measured’ field (4) and click on the sample name to highlight all of the associated vamas blocks to be calibrated (5). Finally, click ‘Apply to selection’ to apply the calibration to all blocks.

 

Repeat the process from example 1 for Si 2p, using 103.5 in th ‘True’ field instead of 284.8 (C 1s). Use the overlay feature to compare your Si 2p spectra and ensure they line up properly – indicating a successful calibration.

 

 

If one (or more) of the calibrations does not look OK, you can reset the calibration using the ‘Processing History’ tab and selecting ‘Reset’

Reset the calibration for each individual element for that sample and start again.

 

 

Use what you have learned to calibrate example 3 to a reference spectra. This sample contains commercial silica with Zr nanoparticles deposited onto it. Calibrate to carbon and silicon and compare using the overlay function to see how well the Si 2p regions line up from the 2 different calibration methods.

The silicon in this example is not expected to contain differing chemistries – however the Zr nanoparticles may have different surface chemistries. You may note that the Si calibration results in a more uniform set of data. This could be due to slight differences in the carbon adsorbates due to different zirconia chemistries.