We employ a 2D, planar computational model to study the effects of ampoule tilting on zinc segregation during the growth of cadmium zinc telluride in a low-gradient vertical Bridgman process. Tilting the axis of the ampoule away from the direction of gravity strongly affects the structure and strength of melt convection, which, in turn, modifies heat transfer and the shape of the solid-liquid interface. While these effects have relatively little direct effect on axial segregation, the pattern of lateral segregation is significantly changed by tilting. Optimal tilt angles are found that locally flatten lateral compositional profiles and that decrease a measure of overall segregation, compared to the case of growth in a perfectly vertical ampoule.
Bibliographical noteFunding Information:
This work was supported in part by the National Aeronautics and Space Administration, under Grant NAG-NNM04AA19G, the National Science Foundation, under Grant no. 0201486, and the Minnesota Supercomputing Institute. We also wish to thank the reviewer for improving the quality of this manuscript.
- A1. Computer simulation
- A1. Convection
- A1. Segregation
- A2. Bridgman technique
- B1. Cadmium compounds