Influence of seed/crystal interface shape on dislocation generation in Czochralski Si crystal growth

Influence of interface shape between a seed and the grown crystal on dislocation generation behavior near the interface in Czochralski-grown Si crystal was investigated using heavily B-doped or heavily B and Ge codoped Si seeds. When the interface shape was convex toward the melt dislocations were generated near the interface, while dislocation generation was suppressed when the shape was planar. The seed with the convex interface sustains larger shear stress than that with the planar interface, and in the case dislocations are generated by thermal stress related to the interface shape at the edge of the interface.