Critical Shape and Size for Dislocation Nucleation in Si{sub 1-x}Ge{sub x} Islands on Si(001)

Journal Article · Fri Dec 07 00:00:00 EST 2007 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.99.235505· OSTI ID:21024546

Marzegalli, A; Zinovyev, V A; Montalenti, F; Miglio, Leo ^[1]; Rastelli, A; Schmidt, O G ^[2]; Stoffel, M; Merdzhanova, T ^[2]

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1. L-NESS and Dipartimento di Scienza dei Materiali, Universita degli Studi di Milano-Bicocca, via Cozzi 53, I-20125 Milan (Italy)
2. Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstrasse 1, 70569 Stuttgart (Germany)

The critical volume for the onset of plastic strain relaxation in SiGe islands on Si(001) is computed for different Ge contents and realistic shapes by using a three-dimensional model, with position-dependent dislocation energy. It turns out that the critical bases for dome- and barnlike islands are different for any composition. By comparison to extensive atomic force microscopy measurements of the footprints left on the Si substrates by islands grown at different temperatures (and compositions), we conclude that, in contrast with planar films, dislocation nucleation in 3D islands is fully thermodynamic.

• OSTI ID: 21024546
• Journal Information: Physical Review Letters, Vol. 99, Issue 23; Other Information: DOI: 10.1103/PhysRevLett.99.235505; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ATOMIC FORCE MICROSCOPY
DISLOCATIONS
FILMS
GERMANIUM SILICIDES
MAGNETIC ISLANDS
NUCLEATION
RELAXATION
STRAINS
SUBSTRATES
THREE-DIMENSIONAL CALCULATIONS