Composition dependence of solid-phase epitaxy in silicon-germanium alloys: Experiment and theory

Journal Article · Wed Mar 15 04:00:00 EST 1995 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.51.7762· OSTI ID:6566204

Haynes, T E ^[1]; Antonell, M J; Lee, C A; Jones, K S ^[2]

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1. Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6048 (United States)
2. Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)

The rates of solid-phase epitaxy (SPE) in unstrained Si[sub 1[minus][ital x]]Ge[sub [ital x]] alloys have been measured by time-resolved reflectivity for eight different alloy compositions, including both Si-rich and Ge-rich layers. Amorphous layers 300--400 nm thick were first formed in 8-[mu]m-thick, relaxed, epitaxial Si[sub 1[minus][ital x]]Ge[sub [ital x]] layers (0.02[le][ital x][le]0.87) by ion implantation of Si[sup +]. For each composition, the measured SPE rates spanned approximately two orders of magnitude. The alloy SPE rates are shown to be related to the regrowth rates of the two pure elements by a simple equation expressed in terms of the composition parameter [ital x] and having no adjustable parameters. The form of this equation implies that crystallization occurs by a serial attachment process at the amorphous-crystal interface and that the rate of attachment of each individual atom is determined by the identities of its four nearest neighbors. Such a process is consistent with the dangling-bond model proposed by Spaepen and Turnbull [in [ital Laser[minus]Solid] [ital Interactions] [ital and] [ital Laser] [ital Processing], edited by S. D. Ferris, H. J. Leamy, and J. M. Poate, AIP Conf. Proc. No. 50 (AIP, New York, 1979)] if the SPE rate is limited by the migration rate of dangling bonds rather than by their formation rate. Based on this analysis, an interpretation is proposed for the anomalously large activation energies that have been measured for SPE in some Si-rich compositions.

• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6566204
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 51:12; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360601* -- Other Materials-- Preparation & Manufacture
ACTIVATION ENERGY
ALLOYS
AMORPHOUS STATE
CHARGED PARTICLES
CRYSTALLIZATION
ENERGY
ENERGY RANGE
EPITAXY
GERMANIUM ALLOYS
ION IMPLANTATION
IONS
KEV RANGE
PHASE TRANSFORMATIONS
PHYSICAL RADIATION EFFECTS
RADIATION EFFECTS
SILICON ALLOYS
SILICON IONS