The microstructure of dislocation clusters in industrial directionally solidified multicrystalline silicon

The microstructure of commonly occurring dislocation patterns in industrial directionally solidified multicrystalline silicon has been systematically studied by light microscopy, electron backscatter diffraction, and transmission electron microscopy. The work has been focused on dislocation clusters on wafers near the top of cast blocks. In near {111} grain surface, dislocation arrays parallel to {110} plane traces are lying in parallel rows of {111} planes inclined to the surface, in mainly 〈112〉 30° orientation. The dislocation configuration suggests that the microstructure may result from a recovery process. The dislocations formed during crystal growth and cooling have undergone transformations at high temperature in order to achieve low energy configurations for minimization of dislocation and crystal energy.