| Autor: |
Eaglesham, D. J., Kvam, E. P., Maher, D. M., Humphreys, C. J., Green, G. S., Tanner, B. K., Bean, J. C. |
| Předmět: |
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| Zdroj: |
Applied Physics Letters; 11/21/1988, Vol. 53 Issue 21, p2083, 3p |
| Abstrakt: |
An x-ray topography study is presented of the coherency breakdown in GexSi1-x/Si(100) strained epilayers. Finite dislocation densities (in excess of 103 cm-2) are observed at compositions in the range 12–13 at. % Ge for an epilayer thickness of h≊180 nm. Above 13 at. % Ge the dislocation density starts to change rapidly and this composition is identified as critical for h≊180 nm, a thickness which is almost a factor of 4 lower than the accepted ‘‘critical’’ thickness for this lattice mismatch. The result suggests that in low-mismatched GexSi1-x alloys the dislocation density will increase continuously at the ‘‘critical’’ thickness, as opposed to exhibiting a sharp onset. The implications of these results to the various models of the critical thickness transition are discussed. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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