Development of coincidence transmission electron microscope. III. Incorporation with gamma-type imaging energy filter

We have developed a new analytical transmission electron microscope (TEM), called coincidence TEM, which, in principle, enables observation of elemental mapping images at a high signal-to-noise ratio. We have previously reported the successful observation of an elemental mapping image of a specimen, but over a very long period of time (168 h). To solve this inefficiency, we installed a gamma-type imaging energy filter in the coincidence TEM to remove the no-loss electrons, which are mainly transmitted electrons. This has enabled the intensity of the background signals in the coincidence measurement to be markedly reduced. The coincidence TEM with a gamma-type imaging energy filter allows the coincidence image to be observed in 3 h, thus, the measurement time is shortened by two orders of magnitude. Moreover, the use of a silicon drift detector (SDD) will shorten the measurement time.