Heat and momentum transport during the horizontal Bridgman (HB) growth of cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) are investigated using a large-scale numerical model. The model employs the Galerkin finite element method to calculate two-dimensional, quasi-steady thermal and velocity fields in the presence of a free boundary, the solidification interface. Of particular interest in this study is the exploration of the shelf growth morphology during the HB growth of CdTe and CdZnTe. Our calculations clearly show that shelf growth naturally arises from simple heat transfer effects in the low-gradient system studied here. We also demonstrate how the shelf shape can be altered by process modifications. These results lend important insight to the benefits of shelf growth for production of CdTe and CdZnTe.
Bibliographical noteFunding Information:
This work was supported in part by Johnson Matthey Electronics, Inc., under contract MDA972-91-C-0046, IR Materials Producibility, from the Advanced Research Projects Agency, Microelectronics Technology Office, and by the National Science Foundation under grant number DMR-9058386. Computational resources were provided by the University of Minnesota Supercomputer Institute and the Army High Performance Computing Research Center under the auspices of the Department of the Army, Army Research Laboratory cooperative agreement DAA1104-95-2-0003/contract DAAI104-95-C-0008, the content of which does not necessarily reflect the position or policy of the government, and no official endorsement should be inferred. We also wish to thank P.-K. Liao of Texas Instruments for providing us with the photograph from his experimental work shown in Fig. 1 and acknowledge the assistance of Jeffrey Fuller of the University of Minnesota for assistance in preparation of some of the figures of this manuscript.
- Cadmium telluride
- Heat transfer
- Horizontal Bridgman