High brightness lattice

The advent of the high brightness lattice at the SRS in 1985 enhanced the focussed beam intensity by a factor of 3. 

Figure 12. Cross-sectional TEM images of a silica sample implanted with Ag and S (a) high-resolution image showing the lattice planes of the Ag2S shell (b) bright-field showing the contrast between the Ag core and the Ag2S shell (c) and (d) are the diffraction pattern of the sample sequentially implanted with S followed by Ag and with Ag followed by S, respectively. (Reprinted from Ref [1], 2005, with permission from Italian Physical Society.)...

The simplest lattice defects as far as FIM observations are concerned are point defects, such as vacancies, self-interstitials and substitutional as well as interstitial impurity atoms. Vacancies invariably show up as dark spots in the field ion images. Other point defects may appear as either bright image spots or vacancies in the image. Thus these defects can be identified from field ion images of high index planes where all the atoms in a plane are fully resolved. 

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