Abstract: | Different types of dislocation bundles were identified in thermally processed (001) GaAs wafers. Synchrotron based single crystal X‐ray transmission topography, scanning infrared polariscopy, visible light interferometry, standard Nomarski microscopy, and Makyoh topography had been applied for this purpose and allowed for a classification of the dislocation bundles into one distinct majority and a generic minority type. The currently accepted theories are briefly discussed and it is shown that their disagreement with the core of the experimental observations is due to oversimplifications. A new theory is finally presented in a concise manner and its excellent agreement with all of the available experimental evidence is demonstrated. |