Towards the three-dimensional field ion microscope

Three-dimensional field ion microscope (FIM) images have been reconstructed using the successive images of an FIM movie. This capability opens a new dimension to the observation with the FIM of various crystallographic features, such as vacancies, dislocations, grain boundaries or precipitates. By piling up the images in a 3D matrix, darkly imaging precipitates in an AlSm alloy are reconstructed in three dimensions. The resolution of the instrument is proved to be better than 0.05 nm in depth and 0.3 nm laterally in favourable cases. This enables a dislocation in Fe to be observed in 3D. Raw reconstructions are, however, slightly distorted. Atomic lines are curved because the basic reconstruction method does not fully take into account the shape of the sample tip. An improved reconstruction method is proposed. Copyright (C) 2007 John Wiley & Sons, Ltd.