The influence of Sb as a surfactant on the strain relaxation of Ge/Si(001)

Conference · · Journal of Vacuum Science and Technology. B, Microelectronics Processing and Phenomena; (United States)

OSTI ID:7115768

Thornton, J M.C.; Williams, A A; Macdonald, J E ^[1]; Silfhout, R.G. van; Veen, J.F. van der ^[2]; Finney, M; Norris, C ^[3]

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1. Univ. of Wales Coll., Cardiff (United Kingdom)
2. FOM Inst. for Atomic and Molecular Physics, Amsterdam (Netherlands)
3. Univ. of Leicester (United Kingdom)

The authors have investigated by the use of surface x-ray diffraction the initial strain relaxation of Ge on Si(001) when a surfactant layer of Sb (0.7 monolayers (ML)) is present. Due to the high sensitivity of the technique to lateral strain in the overlayer, they have been able to observe directly the onset of strain relaxation at a coverage of 9-10 ML. This strain relief proceeds gradually as a function of coverage, but unlike the case without an Sb surfactant, it was not possible to relax the overlayer fully. No bulklike Ge was seen even up to a coverage of {approx}55 ML. Concurrent specular reflectivity measurements also showed that the overlayer formed in a layer-by-layer mode up to the same level. These results differ quite markedly from those obtained without the surfactant layer, where several stages of island formation and strain relaxation are seen. They show dramatically how the modification of surface energies by the presence of a surfactant can affect the morphology of, and strain in, a lattice mismatched overlayer. In addition, they are direct confirmation that the initial strain relaxation mechanism in operation when a surfactant is not present is the formation of coherent Ge islands, rather than that of dislocations.

• OSTI ID: 7115768
• Report Number(s): CONF-910115-; CODEN: JVTBD
• Journal Information: Journal of Vacuum Science and Technology. B, Microelectronics Processing and Phenomena; (United States), Vol. 9:4; Conference: 18. annual conference on physics and chemistry of semiconductor interfaces, Long Beach, CA (United States), 29 Jan - 1 Feb 1991; ISSN 0734-211X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANTIMONY
METALLURGICAL EFFECTS
GERMANIUM
STRESS RELAXATION
SILICON
CRYSTAL LATTICES
MORPHOLOGY
REFLECTIVITY
SPECTRAL REFLECTANCE
SURFACTANTS
X-RAY DIFFRACTION
COHERENT SCATTERING
CRYSTAL STRUCTURE
DIFFRACTION
ELEMENTS
METALS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
RELAXATION
SCATTERING
SEMIMETALS
SURFACE PROPERTIES
360603* - Materials- Properties