X-RAY PLANE-WAVE TOPOGRAPHY OF ANNEALED SILICON-CRYSTALS USING ASYMMETRIC REFLECTIONS

X-ray plane wave topography using asymmetric reflections is used for imaging of microdefects, generated in an annealed Cz-Si crystal wafer. Defects are introduced using metallic contaminants and surface damage before carrying out a rapid thermal annealing (RTA) process. Different contributions to the diffraction pattern from components of the long-range strain field created in the specimen by thermal stress are investigated in the Bragg and Laue cases. The morphology of the microdefects (probably precipitates of metal silicides) is described. The simultaneous existence of large microdefects immersed in a high density distribution of small defects is observed. Large microdefects near the crystal surface are classified into two categories. Images observed for different orientations of the diffraction vector indicate that the elastic field of the large microdefects is close to spherical symmetry.