Shaping the composition profiles in heteroepitaxial quantum dots: Interplay of thermodynamic and kinetic effects

Journal Article · Tue Jul 15 00:00:00 EDT 2014 · AIP Advances

DOI:https://doi.org/10.1063/1.4891935· OSTI ID:22299787

Georgiou, C. ^[1]; Leontiou, T. ^[1]

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1. Research Unit for Nanostructured Materials Systems, Cyprus University of Technology, P.O. Box 50329, 3603 Limassol (Cyprus)

Atomistic Monte Carlo simulations, coupling thermodynamic and kinetic effects, resolve a longstanding controversy regarding the origin of composition profiles in heteroepitaxial SiGe quantum dots. It is shown that profiles with cores rich in the unstrained (Si) component derive from near-equilibrium processes and intraisland diffusion. Profiles with cores rich in the strained (Ge) component are of nonequilibrium nature, i.e., they are strain driven but kinetically limited. They are shaped by the distribution of kinetic barriers of atomic diffusion in the islands. The diffusion pathways are clearly revealed for the first time. Geometrical kinetics play a minor role.

• OSTI ID: 22299787
• Journal Information: AIP Advances, Vol. 4, Issue 7; Other Information: (c) 2014 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 2158-3226
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPUTERIZED SIMULATION
COUPLING
GERMANIUM SILICIDES
KINETICS
MONTE CARLO METHOD
QUANTUM DOTS