• Applied Microscopy
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• v.38 no.4
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• pp.363-374
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• 2008

In this paper we have examined the usefulness of IWFR (the iterative wave-function reconstruction) analysis for through-focal series of high-resolution images for a relative thick crystal. In the work we employed JEOL ARM 1300S, and observed the high-resolution images for a Si crystal at the two orientations of [01-1] and [11-2] having 30 nm and 35 nm thickness respectively. As a result of applying IWFR method on the images we found out that even for a thick crystal by the method we can retrieve the exit-surface wave function. However because of the strong dynamical scattering effect, the image pattern of the function reflects only qualitatively the atomic column structure of the crystal examined. Nevertheless it is no doubt that the pattern would give important clue for the crystal structure.

• Applied Microscopy
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• v.38 no.1
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• pp.63-72
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• 2008

The iterative wave-function reconstruction (IWFR) method developed by Allen et al. (2004) was reviewed with concern for its applicability. The high resolution transmission electron microscopy (HRTEM) studies of the materials such as GaAs, $YBa_2Cu_3O_7$ and $Al_2CuMg$ reported in the literature were utilized in this review. In this process the basis of validity, the limiting conditions and the information limit of this method were discussed. It was particularly noted that the phase contrast image of the exit plane wave evaluated from this method reveals not only $C_s$-corrected atomic resolution within information limit, but also strong tendency of contrast proportional to the magnitude of the atomic number of compositional atoms in a crystal.