Different holders

The following holders can be used in the cryo STXM:

• A JEOL room temperature holder. The specimen is mounted by gluing or taping it (with Carbon double sticky tape) to a metal shim that is screwed to the holder. The holder is used with a pinhole or testpattern during alignment, or with dry samples.
• A cryo holder from Fischione Instruments. This holder is designed to hold a frozen specimen on a 3 mm TEM grid with a special screw. In addition, it has a pinhole mounted permanently, and sometimes even a testpattern. The holder is designed for tilting up to $\pm 60^o$. The holder tip is delicate and the sapphire tip is quite fragile, so it must be handled with care.
• A Fischione cryo holder that belongs to the X-ray Optics Group at Lawrence Berkeley National Laboratory is available at most times. Many thanks to Malcolm Howells et al. for that. While this holder serves as a nice fallback option, it is not recommended to use it for actual data taking. The holder was not purchased for this microscope, and while it fits into the airlock, it is missing the second pin on the barrel that is necessary to rigidly connect it with the scanning stage. Therefore, images acquired with this holder will likely show vibrations and therefore reduced spatial resolution. Also, this holder is not optimized for tilting, but allows it for a smaller range of angles. Its tip is in some ways even more fragile, care has to be taking to not bend it or break the sapphire during operation, especially during tilting (see section on tilting during imaging).
• The Oxford Holder: This holder gives the best image quality! (Which, on second thought, is the minimum you would expect for its price ...) Its dewar is considerably smaller than the dewars of the Fischione holders. It turns out that it has to be pumped at least overnight and baked to get it to hold low temperatures. Also, it will not cool down as far as the Fischione holders in its workstation, but it reaches below liquid nitrogen temperature when inserted into the microscope.

  The tip of the Oxford holder looks more similar to the JEOL holder than to a Fischione holder. However, it is designed to allow tilt to $\pm 60^o$.

NOTE: We have recently established that the image quality (speak absence of vibrations) depends crucially on correct airlock preload. The values are different for each holder and need to be adjusted accordingly before inserting the holder: