For a quantitative analysis of thickness measurements using XRF I need reliable and accurate information from other methods, e.g. RBS. Typical applications are single layers as Rh foils or multilayeres samples ranging approx. from 0 to 100 µm. I would like to build up a long-term collaboration.
High quality RBS measurement for layer thickness (probably using the codes RUMP or SIMNRA). First of all this technique is not very well adapted to accurate measurement of the thickness. It depends on what you call thickness and what is the atomic mass of your material. Generally the accuracy is not better than 50 angstroms. If you want better results you must use the MEIS technique which use helium at rather low energy. An other possibility is the X ray reflectometry technique which can give an accuracy some time better than ten angstroms.
The best technique of course is a cross section HRTEM image.
For good RBS measurements in France:
CNSM lab in Paris
INSB institute Paris 7 Jussieu
Phase lab in Strasbourg
Large Scale Facility sponsored by EU, INFN Legnaro Italy close to Padua.
Valentino Rigato can be one of the contact person.
A happy new year to you all and thank you for your answers. As I understand MEIS is much more accurate than RBS but should be more sensitive to surface properties and layer thickness on the nm scale. Is this correct ?
You might like to look at the EU I3 project SPIRIT (http://www.spiit-ion.eu) which provides ion beam facilities across Europe for free. It can provide RBS at Surrey, Dresden, Paris, Leuven, Bordeaux, Zagreb and Slovenia. MEIS is also available in Paris. For free access you have to use transnational facilities - that is if you are in Germany you can not use a German facility, but any of the others are open to you. At Surrey we have been providing RBS services on film thickness measurements as part of a National Centre for more than 30 years. From the range of thcknesses you mention RBS will be better suited as MEIS is too sensitive ie it wont measure your thicker samples. We have a bespoke analysis package (DataFurnace) produced at Surrey and Lisbon which is ideal for interpreting the RBS data for thin films. The only problem - as mentioned n some of the previous answers - is that RBS (and MEIS) only tell you the number of atoms passed by the beam, to turn this into a depth in nm an atomic density of the material has to be assumed. Otherwise I believe RBS is the ideal for what you want to do.
At first glance, 3 MeV RBS alpha can measure 1monolayer to about 3 micro meter.
For single layers, you may consider High-resolution RBS (HRBS), which is capable of monolayer depth resolution for thin films of nm range. You may like to look at our HRBS facilities here at the Centre for Ion Beam Applications (CIBA) at NUS:
http://www.ciba.nus.edu.sg/publications/fac/fac2006_1.pdf
We also do a lot of work on conventional RBS as well as other methods of IBA.
- Badges
- Science topic
- Similar topics
- Chemistry
- Nanotechnology
- Nanostructures
- Thin Films