Sample Requirements for Analyses with the Cameca NanoSIMS 50L
Please contact the nanoSOIL team at the TUM, Lehrstuhl für Bodenkunde in Freising directly to discuss sample requirements.
As part of the nanoSOIL team, Carmen Hoeschen will assist you with questions concerning the physical background, the measurement procedure and operational demands of the NanoSIMS technique. Steffen Schweizer will assist you with questions concerning the planning of experiments and by discussing possible sample preparation techniques.
The following is a brief outline of sample requirements to determine if your samples may be suitable. These requirements will be checked in the measurement application form!
- The sample has to be stable under vacuum of up to 10-11 mbar!
- The surface of the sample has to be polished! If the analyses of single particles on sample holders (e.g. Al, Ti or Si substrate) or on filters is planned, it has to be ensured that the particles are tightly attached to the sample holder / substrate surface and the topography of the grains is below 10 ?m!
- The maximum thickness of the samples to fit in the sample holders is 5 mm.
- The surface has to be perpendicular to the cylindrical sample holders (Photo 1)! Current NanoSIMS sample holders are able to hold circular shaped mounts 10 mm, 12 mm, and one-inch in diameter. Geology holders (Photo 3) can each hold 1 one-inch round, 2 x 10 mm stubs, and 2 x 12 mm stubs. Biology holders can hold up to 8 x 10 mm stubs. Additionally, we are able to mount filter samples with a diameter of 5 mm (24 samples per sample holder).
- In order to analyse meaningful spots on the samples, an accurate documentation from light microscopy to SEM or TEM or comparable techniques is mandatory! Possible ways to transform coordinates between SEM/TEM and NanoSIMS and ways to relocate regions of interest have to be discussed with the nanoSOIL team before any microscopic analyses!
- The analysis time will be more efficient, when replicates and/or additional samples are mounted on the same sample holder!
- If the samples are not electrically conductive, a coating layer with a conductive material is needed. This can be applied also at the nanoSOIL laboratory.




Probenvorbereitung
We are able to provide a variety of different sample holders, which range from suiting filter pieces with a diameter of 5 mm to up to samples with a maximal diameter of 2.5 cm. On a daily basis we are currently working with sample holders suiting metal stubs or resin blocks with 10 mm diameter.


At the moment we use two main sample preparation techniques:
- Precipitation of single grain mixtures as liquid suspension on clean (cleaning with Acetone) Si-wafers, Ga-wafers, polished Al-stubs and Ti-stubs
- Embedding of larger samples in epoxy resin with subsequent sectioning and polishing
Additional preparation techniques, feasible for soil science related sample properties, are currently tested.
To ensure an accurate NanoSIMS analysis of your samples it is crucial to contact us prior to any sample preparation, due to the special requirements of the NanoSIMS measurement.
Please also feel free to contact us for further questions, protocols and possible different preparation methods.