Distinguishing glide and shuffle types for 60° dislocation in semicoductors by field-emission HREM image processing

High-resolution electron microscope images were simulated for two structural models of Si crystal containing the 60° dislocation of glide and shuffle types, respectively. The electron optical parameters for the image simulation were used by referring to a 200 kV field-emission high-resolution microscope. Since the contrast difference for the two types of dislocations is not significant enough for the eye to distinguish, it is impossible to determine the type of a dislocation from the image directly. Image reconstruction has been carried out by means of the image deconvolution technique. In the reconstructed images all atoms resolved individually and the two types of 60° dislocations can be distinguished clearly.The effect and the limit of the method are discussed.