Thermal processing induced plastic deformation in GaAs wafers

Different types of dislocation bundles were identified in the (001) GaAs substrates of III–V heterostructures. Comparisons of scanning infrared polariscopy images and X-ray transmission topograms showed a one to one correlation of stripes of reduced residual shear strain and dislocation bundles of the majority type. Visible-light interferometry and Makyoh topography, on the other hand, showed a slip-line distribution that is in correspondence to the distribution of dislocation bundles of the minority type(s). A new model for the plastic deformation of circular GaAs wafers during thermal processing is briefly outlined and its good agreement with the main experimental results demonstrated.