Calculated asymmetry for weak beam intrinsic stacking fault images

Abstract

Multislice calculations have been performed to obtain weak beam images for both extrinsic and intrinsic inclined stacking faults in silicon. A comparison of these results with results from kinematical and two-beam column approximation calculations is made. The multislice results are found to be different, particularly for the intrinsic case where, unlike the other two calculation methods, an appreciable asymmetry between ± g image pairs is predicted. This is thought to be due to the better modelling in the multislice calculation of the atomic potential in the region of the fault.

The effects of small tilts (i.e. changes in excitation error) and beam divergence on the intrinsic stacking fault contrast are also investigated using the multislice technique. The results indicate that it should be relatively easy to observe experimentally the ± g weak beam image asymmetry predicted above.