Single Crystal Cadmium Telluride High Energy IR Laser Windows.
Final rechnical rept. 1 Jun 71-29 Feb 72,
TEXAS INSTRUMENTS INC DALLAS
Pagination or Media Count:
The goal of this program was to grow thick, large-area plates of CdTe using a solution epitaxy method. Solution epitaxy was chosen as the method for growth in the belief that fast reaction rates could be obtained at lower temperatures than those used for vapor growth. Operating at a temperature well below the wide existance region found for CdTe would reduce the trouble with impurities and lead to greater control of stoichiometry. Generally, solution epitaxy is a batch process used to grow thin layers. The process as used is rate-limited by diffusion of one constitutent through the solution. Mechanical motion of the solution was used in an effort to overcome the batch-type nature of the process. Motion of the solution in the vicinity of the substrate led to extremely irregular layer growth along with spontaneous nucleation and growth of CdTe dendrites and platelets. Solution entrainment was observed for all deposits. Solution growth is not a good method of forming thick pieces of CdTe. For the finished process, the large-area substrate would be a mosaic made up of pieces of single crystal CdTe cut from a crystal grown in a conventional manner. Several methods of fabricating the substrate are discussed, along with efforts to alloy the mosaic pieces together. Author
- Infrared Detection and Detectors