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X-Ray Photoelectron Spectroscopy (XPS): |
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Instrumentation and working
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Basic components of XPS instrumentation are: |
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1. Source, 2. Sample Holder, 3. Analyzer, 4.Detector and 5. Signal Processor |
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Source: A common source is an X-ray tube with both Al or Mg target and a suitable filter. For the analysis of heavy elements Cu, Mn and Ag targets with suitable filters are used. |
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Sample holder: Samples like a piece of metal are mounted close to source, which is evacuated upto 10-9 torr to avoid contamination by oxygen and water vapors. |
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Analyzer: Hemispheric analyzers are used to distinguish electrons of different energies by applying electrostatic and magnetic fields. |
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Detector and signal Processor: Usually Channeltrons or solid-state detectors are used to attain required sensitivities. |
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Figure 37.2 Block diagram of X-ray Photoelectron Spectroscopy |
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Surface analysis for elemental composition.
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To determine different oxidation states of the elements. |
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For structural analysis of molecules. |
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It is also useful for qualitative analysis of the surfaces. |
