Cleaning TEM Holders

Under Construction!

While the JEOL JEM 3200FS uses an ion-pump based vacuum system to keep the column vacuum at the normal operating vacuum, the JEOL JEM 1400plus uses an oil-based vacuum system for its column vacuum. This leads to the situation where specimen holders inside the 1400plus can acquire a very thin layer of oil during normal operation. Even though this potential layer of oil is very thin, transferring such a "dirty" holder directly into the 3200FS can contaminate the column vacuum and lead to general problems with contamination using that instrument. For this reason, the following protocol has been established for cleaning a holder when transferring it from the 1400plus to the 3200FS:

  1. Clean the holder from the tip (specimen holding region) to the first O-ring using an organic solvent such as 100% ethanol or EM grade chloroform.

  2. After allowing the holder to air dry for several minutes, place the cleaned holder into one of the ports of the Gatan dry pumping station in SI 032A and pump the system overnight.

A similar cleaning procedure can be performed on just the "retainer" portion of some of the holders (e.g., the high tilt retainer (HTR) or the single tilt beryllium holder) if and only if the user uses a different specimen rod that is appropriate for the different microscopes. In this situation, the user can either attach the retainer to a specimen rod and pump overnight as outlined above, or the retainer can be heated overnight in the 50° oven in the Simon Hall EM room.

NOTE: The EMC is trying to obtain funds to purchase an Ar/O plasma cleaner that would be able to clean the TEM holders for our electron microscopes. Such a device would also make this sort of cleaning much faster and easier.