Jump to content

Specific Process Knowledge/Characterization/Element analysis: Difference between revisions

← Older editNewer edit →
VisualWikitext
Kn (talk | contribs)
danchip
979 edits
No edit summary
Kn (talk | contribs)
danchip
979 edits
No edit summary
Line 1: Line 1:
== Instruments at Danchip ==
== Instruments at Danchip ==


You can make detailed analysis on the elemental composition and distribution in a sample with 4 instruments at Danchip. The [[Specific Process Knowledge/Characterization/SEM: Scanning Electron Microscopy/Leo|Leo SEM]] and [[Specific Process Knowledge/Characterization/SEM: Scanning Electron Microscopy/FEI|FEI SEM]] are both equipped with an X-ray detector that allows you to make elemental analysis by using the technique Energy Dispersive X-ray analysis or EDX. The [[Specific Process Knowledge/Characterization/SIMS: Secondary Ion Mass Spectrometry|Atomika SIMS]] uses a technique called Secondary Ion Mass Spectrometry or SIMS. The [[Specific Process Knowledge/Characterization/XPS|XPS-ThermoScientific]] can be used for X-ray Photoelectron spectroscopy measurements.  
You can make detailed analysis on the elemental composition and distribution in a sample with 4 instruments at Danchip. The [[Specific Process Knowledge/Characterization/SEM: Scanning Electron Microscopy/Leo|Leo SEM]] and [[Specific Process Knowledge/Characterization/SEM: Scanning Electron Microscopy/FEI|FEI SEM]] are both equipped with an X-ray detector that allows you to make elemental analysis by using the technique Energy Dispersive X-ray analysis or EDX. The [[Specific Process Knowledge/Characterization/SIMS: Secondary Ion Mass Spectrometry|Atomika SIMS]] uses a technique called Secondary Ion Mass Spectrometry or SIMS. The [[Specific Process Knowledge/Characterization/XPS|XPS-ThermoScientific]] can be used for X-ray Photoelectron Spectroscopy measurements.  




Line 33: Line 33:
During a XPS (X-ray Photoelectron Spectroscopy) analysis, the sample is irradiated with photons of a specific energy (in the Danchip system 1486 eV). When energy of the irradiating X-rays is adsorbed by the atoms in the sample, photoelectrons are ejected [[http://en.wikipedia.org/wiki/Photoelectric_effect]].  
During a XPS (X-ray Photoelectron Spectroscopy) analysis, the sample is irradiated with photons of a specific energy (in the Danchip system 1486 eV). When energy of the irradiating X-rays is adsorbed by the atoms in the sample, photoelectrons are ejected [[http://en.wikipedia.org/wiki/Photoelectric_effect]].  


Since the energy of the incoming photons is known, and the energy of the ejected electrons is measured, the binding energy of the electrons in the probed atoms can be known. The binding energy of the electrons are element specific, and is therefore a "finger-print" of the atom. Hence, a measurement of the XPS spectrum gives information of which materials are present in the sample, and at which concentrations.  
Since the energy of the incoming photons is known, and the energy of the ejected electrons is measured, the binding energy of the electrons in the probed atoms can be determined. The binding energy of the electrons are element specific, and is therefore a "finger-print" of the atom. Hence, a measurement of the XPS spectrum gives information of which materials are present in the sample, and at which concentrations.  


 
XPS is an excellent technique to probe the chemical state of atoms on a surface. The binding energy of lower lying atomic levels (for example 1s, 2s and 2p) are at a specific energy, but is slightly affected by the chemical environment of the probed atom. This is known as the '''chemical shift'''. By measuring the shift of the electron binding energies one can determined the chemical state of atoms. See an example on the page [[Specific Process Knowledge/Characterization/XPS|XPS-ThermoScientific]].
XPS is an excellent technique to probe the chemical state of atoms on a surface. The binding energy of lower lying atomic levels (for example 1s, 2s and 2p) are at a specific energy, but is slightly affected by the chemical environment of the probed atom. This is known as the '''chemical shift''', and the information from measuring the shift of the electron binding energies can be used to know the chemical state of atoms. See an example on the page [[Specific Process Knowledge/Characterization/XPS|XPS-ThermoScientific]].




Line 70: Line 69:
|| Vacuum compatible.
|| Vacuum compatible.
|| Vacuum compatible. The sample needs to be cut into small (app. 5*5 mm) pieces.
|| Vacuum compatible. The sample needs to be cut into small (app. 5*5 mm) pieces.
|| Vacuum compatible.
|| Vacuum compatible. Sample size max 50x50 mm, thickness max 20 mm.
|-
|-
!  Spatial resolution
!  Spatial resolution
Line 110: Line 109:
* Do an elemental analysis of the outermost layer of your surface.
* Do an elemental analysis of the outermost layer of your surface.
* Check the composition of a film at different depths.
* Check the composition of a film at different depths.
* Checking for a contamination.  
* Check for a contaminations.  
** It not as sensitive as the SIMS, but faster, so it can be an alternative if you are checking for higher contamination levels (like 1 %)
** It not as sensitive as the SIMS, but faster, so it can be an alternative if you are checking for a bit higher contamination levels (like 1 %)
* Do a analysis of the chemical state of atoms present on the surface.
* Do a analysis of the chemical state of atoms present on the surface.
** See what effect a surface treatment of your sample has on the surface chemistry.
** See what effect a surface treatment of your sample has on the surface chemistry.
Retrieved from "https://labadviser.nanolab.dtu.dk//index.php?title=Specific_Process_Knowledge/Characterization/Element_analysis"