In the past three chapters we’ve described the sources, lenses, and detectors that make up a TEM. The only other parts of the instrument you need to know about in detail are those that, if you are not careful, can seriously degrade the quality of the information you generate even if the rest is perfect. These two parts are the holder in which you put your specimen and the vacuum that surrounds it. While there isn’t much you can do to improve the vacuum, beyond buying a better microscope, there is a lot you can do that will degrade the quality of the vacuum in the column and, in doing so, contaminate your specimen. So we’ll tell you a few basics about how the vacuum pumps work, and how the vacuum system is put together. Although the vacuum system is under computer control in most TEMs, you still affect the vacuum by what you put in the microscope. Consequently, you need to know what not to do on those occasions when you might otherwise degrade the vacuum.
KeywordsSpecimen Holder Leak Detection Diffusion Pump Mechanical Pump Butterfly Valve
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- There is a great deal of history for you to explore when you have time. Why are specimens 2.3 or 3.05 mm diameter? Why do we talk about loading the plates? In many cases, this history holds us back but we often don’t recognize why!Google Scholar
- A more detailed list of references is given in the chapter on in situ TEM in the companion text. For a full exposition of vacuum technology for TEMs, read Bigelow or the equally informative user’s guide by O’Hanlon.Google Scholar
- Bigelow, WC 1995 Vacuum Methods in Electron Microscopy in Practical Methods in Electron Microscopy 15 Ed. AM Glauert Portland Press London. An essential reference.Google Scholar
- O’Hanlon, JF 1981 A User's Guide to Vacuum Technology John Wiley and Sons New York.Google Scholar
Holders and in Situ
- Butler, EP and Hale, KF 1981 Dynamic Experiments in the Electron Microscope in Practical Methods in Electron Microscopy 9 Ed AM Glauert Elsevier Amsterdam.Google Scholar
- Watt, IM 1985 The Principles and Practice of Electron Microscopy Cambridge University Press New York. See appendix 1.Google Scholar
- Komatsu, M, Mori, H and Iwasaki, K 1994 Design of a Hot Tensile Stage for an Ultrahigh-voltage Electron Microscope and Its Application to In Situ Deformation of Sapphire at 1620 and 1720 K J. Am. Ceram. Soc. 77 839–842. Illustrates the use of temperatures as high as 2300 K.Google Scholar
- Valdrè, U and Goringe, MJ 1971 in Electron Microscopy in Material Science, 208–254 Ed. U Valdrè Academic Press New York. This article gives a detailed description of several TEM holders.Google Scholar