| Autor: |
Robert F. Hicks, M. J. Begarney, M. L. Warddrip, M. J. Kappers |
| Rok vydání: |
1998 |
| Předmět: |
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| Zdroj: |
Journal of Crystal Growth. 193:305-315 |
| ISSN: |
0022-0248 |
| Popis: |
Carbon tetrachloride is used to dope gallium arsenide and indium—gallium arsenide films with carbon during metalorganic vapor-phase epitaxy (MOVPE). In this study, the decomposition kinetics of CCl 4 and of the other precursors (triethylgallium, trimethylindium and tertiarybutylarsine) were determined by monitoring the reactor feed and e§uent gases with on-line infrared and mass spectroscopies. As the CCl 4 partial pressure was increased from 1]10~4 to 3]10~3 atm, the GaAs growth rate decreased and eventually fell to zero. Most of the reduction in growth rate (80 to 95%) was due to a surface reaction between adsorbed gallium and chlorine to produce volatile GaCl. The etching of the GaAs film by adsorbed chlorine to produce GaCl 3 accounted for the remainder of the growth rate reduction. The latter reaction was insignificant below a threshold CCl 4 partial pressure of &1.5]10~3 atm at 450iC and &8.0]10~4 atm at 550iC. A comparison of GaAs and InAs MOVPE revealed that the reaction of CCl 4 with indium to form volatile metal chlorides was nearly 10 times faster than the equivalent reactions with gallium. ( 1998 Elsevier Science B.V. All rights reserved. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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