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Vapor crystal growth technology development: application to cadmium telluride
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Duval, Walter M. B. Rosenberger, Franz Banish, Michael |
| Copyright Year | 1991 |
| Description | Growth of bulk crystals by physical vapor transport was developed and applied to cadmium telluride. The technology makes use of effusive ampoules, in which part of the vapor contents escapes to a vacuum shroud through defined leaks during the growth process. This approach has the advantage over traditional sealed ampoule techniques that impurity vapors and excess vapor constituents are continuously removed from the vicinity of the growing crystal. Thus, growth rates are obtained routinely at magnitudes that are rather difficult to achieve in closed ampoules. Other advantages of this effusive ampoule physical vapor transport (EAPVT) technique include the predetermination of transport rates based on simple fluid dynamics and engineering considerations, and the growth of the crystal from close to congruent vapors, which largely alleviates the compositional nonuniformities resulting from buoyancy driven convective transport. After concisely reviewing earlier work on improving transport rates, nucleation control, and minimization of crystal wall interactions in vapor crystal growth, a detail account is given of the largely computer controlled EAPVT experimentation. |
| File Size | 22142345 |
| Page Count | 55 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19920006940 |
| Archival Resource Key | ark:/13960/t78s9n76f |
| Language | English |
| Publisher Date | 1991-12-01 |
| Access Restriction | Open |
| Subject Keyword | Materials Processing Crystal Growth Leakage Nucleation Fluid Dynamics Shrouds Vapors Buoyancy Convective Flow Single Crystals Vapor Deposition Vacuum Impurities Ampoules Melts Crystal Growth Cadmium Tellurides Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
