Microdiffraction imaging of dislocation densities in microstructured samples

A full field X-ray microdiffraction technique is developed providing simultaneously both micrometer-resolved information of crystalline perfection as well as statistical information about the macroscopically illuminated sample. The method allows a detailed characterization of patterned substrates grown by epitaxial lateral overgrowth. Local wing tilts and their fluctuation over the sample area as well as the local and average number of grains in the wings are determined, and the reduction of threading dislocation densities in the grains of the ELO wings can be quantitatively estimated.