Quantitative comparison of surface morphology and reflection high-energy electron diffraction intensity for epitaxial growth on GaAs

Citation
Gr. Bell et al., Quantitative comparison of surface morphology and reflection high-energy electron diffraction intensity for epitaxial growth on GaAs, SURF SCI, 458(1-3), 2000, pp. 247-256
Citations number
19
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
SURFACE SCIENCE
ISSN journal
0039-6028 → ACNP
Volume
458
Issue
1-3
Year of publication
2000
Pages
247 - 256
Database
ISI
SICI code
0039-6028(20000620)458:1-3<247:QCOSMA>2.0.ZU;2-O
Abstract
The relationship between developing surface morphology and specular spot in tensity in reflection high-energy diffraction (RHEED) has been investigated during the homoepitaxial growth of GaAs on various surface orientations. T he 'morphological' quantities of step density and effective coverage have b een measured directly by means of rapid-quench scanning tunnelling microsco py (STM). For growth on the singular (001), (110) and (111)A surfaces, the step density, layer coverage and RHEED intensity oscillate with a period of one monolayer and little damping. The morphological quantities are always in phase, while the phase of the RHEED intensity depends on the diffraction conditions. On vicinal GaAs(001), the RHEED intensity oscillations are rap idly damped, as are oscillations of the morphological quantities, but again the phase of the RHEED intensity can be varied with respect to the other t wo. In all cases on the (001) surface, a well-ordered (2 x 4) surface recon struction develops very rapidly in the growing layer. Implications for theo ries of RHEED intensity oscillations are discussed. (C) 2000 Elsevier Scien ce B.V. All rights reserved.