Numerical and experimental investigation of CdZnTe growth by the boron oxide encapsulated vertical Bridgman method

Cadmium zinc telluride crystals of 4.8 cm in diameter grown by the boron oxide encapsulated vertical Bridgman technique exhibit good structural quality with large grains and low dislocation density. However, ingots contain Te inclusions, which are trapped at growth interface during crystallization process. Global modeling furnace was applied order to investigate temperature gradients evolution shape this system. Transient computations, include crucible movement, show that crystal-melt is concave toward melt conical part ampoule, then becomes convex cylindrical ampoule. Concave shapes very homogeneous distribution beginning solidification process promote a polycrystalline material. A novel hypothesis explaining mechanism grain formation ampoule tip formulated. Our calculations anomalous Zn segregation due poor solute mixing The standard reveals crystal (2-4 K/cm). Such not favorable eliminate inclusions as crystal. numerical model employed analyze field influence on migration/size reduction inclusions.