Abstract
The growth of high-quality relaxed SiGe epilayer has been achieved by introducing an intermediate Si layer in the SiGe film. It was found that intermediate Si in the SiGe film changed the mechanism of strain relaxation during the growth so that the shallow pits related to strain relief on the surface were suppressed. Such a SiGe/Si/SiGe heterostructure has a threading dislocation density of 8.9 × 105 cm-2 and a root mean square roughness of 3 nm. The intermediate Si layer was also demonstrated to act as effective nucleation site for dislocation loops to relax the mismatch strain. A mechanism of strain relaxation for this intermediate Si layer is proposed. Compared with the conventional compositionally graded buffer layer, it has the advantages of having thinner buffer layer for required degree of relaxation, smoother surface, and maintaining the threading dislocation density at the same level.
Original language | English |
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Pages (from-to) | 302-305 |
Number of pages | 4 |
Journal | Thin Solid Films |
Volume | 447-448 |
DOIs | |
State | Published - 30 Jan 2004 |
Event | Proceedings of the 30th International Conference on Metallurgie - San Diego, CA, United States Duration: 28 Apr 2002 → 2 May 2002 |
Keywords
- Intermediate Si layer
- Root mean square roughness
- SiGe films
- Threading dislocation density