TEM: FEI Tecnai Transmission Electron Microscope
The FEI Tecnai G2 F20 X-TWIN Transmission Electron Microscope has a field-emission gun (FEG) for high brightness and coherency, STEM imaging with both EDS and EELS analytical analysis capabilities, and CCD camera for standard TEM imaging.
The Tecnai specifications are as follows:
- 2.5 Å point-to-point resolution, 1.02 Å line resolution, 1.4 Å information limit
- 200kV operating voltage
- ±30° tilt single tilt holder and low-background double-tilt holder
- Gatan SC200 camera for standard TEM imaging and US1000 camera mounted behind the GIF for EF-TEM
- BF/DF STEM detectors
- EDAX thin window Si(Li) detector with 0.3 srad EDS solid angle
To become a qualified user on the FEI Tecnai TEM, follow each of the following steps:
- Complete the process to become a lab member of SNSF and follow the instructions to activate a Badger account.
- Add yourself to the Tecnai users mailing list to receive system status updates by going to http://mailman.stanford.edu, scrolling down to "Manage Subscriptions" and searching "tecnai_users"; fill out the information requested to subscribe.
- Complete the training request form to coordinate subsequent training. Basic Tecnai training typically consists of three 2-hr sessions followed by observation sessions during start-up during your initial independent sessions. Further training on specific techniques can be requested following basic training (STEM, EDS, etc.). TEM users with prior experience will be trained at the level required. An accredited TEM laboratory course is periodically offered through the Materials Science and Engineering Department.
Training in TEM specimen preparation is also available. A variety of techniques and instruments available for thinning materials to the required specifications. Please refer to the TEM specimen preparation page for more details.
Restrictions on Samples: Sample preparation for TEM generally requires more time and experience than for most other characterization techniques. A TEM specimen must be approximately 100 nm or less in thickness in the area of interest. The main specimen supports must fit into a 3mm diameter cup and be - ideally - less than 100 microns in thickness. Specimen preparation possibilities include direct deposition onto a TEM-thin substrate (Si3N4, carbon); direct dispersion of powders on such a substrate; grinding and polishing using special devices (t-tool, tripod); chemical etching and electropolishing; lithographic patterning of walls and pillars for cross-section viewing; and focused ion beam (FIB) sectioning for site specific samples.
TEM service is available for projects where extensive instrument training is not practical. However, users must generally make or provide their own TEM-ready samples.