Difference between revisions of "Photoelectron Spectrometer XPS and UPS"

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(New page: What is the Problem? OLEDs and OPVs consist of thin films of organic materials, sandwiched between contacting electrodes. We need analytical tools which tell us: *Elemental composition o...)
 
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We use high-vacuum surface electron spectroscopies: X-ray photoelectron spectroscopy and UV-photoelectron spectroscopy to provide the elemental, molecular and energetic information we require about these materials.
We use high-vacuum surface electron spectroscopies: X-ray photoelectron spectroscopy and UV-photoelectron spectroscopy to provide the elemental, molecular and energetic information we require about these materials.


XPS uses high energy X-ray photons to excite “core” electrons in the near-surface region  UPS uses lower energy photons in the deep UV region to excite valence electrons.[[Image:Example.jpg]]
XPS uses high energy X-ray photons to excite “core” electrons in the near-surface region  UPS uses lower energy photons in the deep UV region to excite valence electrons.[[Image:http://depts.washington.edu/cmditr/mediawiki/images/thumb/a/a5/Surface_electron_spectroscopiesl.jpg/800px-Surface_electron_spectroscopiesl.jpg]]

Revision as of 12:42, 21 April 2009

What is the Problem? OLEDs and OPVs consist of thin films of organic materials, sandwiched between contacting electrodes. We need analytical tools which tell us:

  • Elemental composition of metal, metal oxide and organic surfaces (top 1-10 nm)
  • The molecular state of those elements in that same region
  • The frontier orbital energies which control rates of charge transfer, photopotentials, onset voltages, etc.

What is our approach? We use high-vacuum surface electron spectroscopies: X-ray photoelectron spectroscopy and UV-photoelectron spectroscopy to provide the elemental, molecular and energetic information we require about these materials.

XPS uses high energy X-ray photons to excite “core” electrons in the near-surface region UPS uses lower energy photons in the deep UV region to excite valence electrons.File:Http://depts.washington.edu/cmditr/mediawiki/images/thumb/a/a5/Surface electron spectroscopiesl.jpg/800px-Surface electron spectroscopiesl.jpg