Field emission guns

S5mthetic resin-embedded alfalfa samples were oven dried at 65 °C for 24 h and cut at 40-90 nm. The slides were analyzed using a JEOL 2010-F TEM prepared with field emission gun, EDS, and a high angle annular dark field detector for the analysis of solitary nanoparticles. 

The electron probe can be from < 1 nm to 10 nm in diameter, and positioned to localize the analytical signals. To obtain the smallest electron probe, a field-emission gun (FEG) is essential, and microanalysis is accomplished using an XEDS and/or an... 

Diffuse reflectance infrared Fourier transform spectroscopy deuterium triglycine sulphate energy compensated atom probe energy dispersive analysis energy-loss near edge structure electron probe X-ray microanalysis elastic recoil detection analysis (see also FreS) electron spectroscopy for chemical analysis extended energy-loss fine structure field emission gun focused ion beam field ion microscope... 

To a limited extent, the type of results reported here could be obtained with a TEM instrument fitted with a STEM adapter, especially if a field-emission gun is used (10). We will refer here, however, only to the use of dedicated STEM instruments such as the HB5 or HB501 made by VG Microscopes Ltd. having a cold field emission gun. Most of the instruments of this type are specialized for microanalysis using EDS or ELS and some have been applied very effectively for compositional analysis and associated studies on catalyst particles, as reported elsewhere in this volume. 

For a microscope equipped with a LaBe gun, the information limit goes not much beyond the point resolution, but, for a field emission gun (FEG) instrument, the information limit is far below the point resolution. For example, the point resolution of a Tecnai F30 S-TWIN is 2.0 A, but an information limit of 1.1 A is attainable. 

Flash cooling of samples, the use of field-emission guns to generate more coherent electron beams, and improved software has radically extended the power of electron microscopy, so that it is now almost routine to provide structural information for viruses to better than 10 A, and sometimes 7 A resolution (Conway et al., 1997). The major strength... 

Transmission electron microscopy (TEM) has traditionally been the mainstay of morphological investigations of polyolefins [8], but recent developments in low voltage high-resolution field emission gun scanning electron microscopy (FEG-SEM) [9] and the advent of atomic force microscopy (AFM) and related near-field techniques [10] have challenged its dominance at the length scales of the order of 10 nm, characteristic of both microdeformation (cavitation, fibrils) and structural components of semicrystalline... 

Sasaki T, et al. Performance of low-voltage STEM/TEM with delta corrector and cold field emission gun. J Electron Microsc. 2010 59 S7-S13. 

---