GaAs structures with InAs and As quantum dots produced in a single molecular beam epitaxy process

Journal Article · Tue Dec 15 00:00:00 EST 2009 · Semiconductors

DOI:https://doi.org/10.1134/S1063782609120082· OSTI ID:21562389

Bert, N A; Preobrazhenskii, V V; Putyato, M A; Semyagin, B R ^[1]

---

1. Russian Academy of Sciences, Institute of Semiconductor Physics, Siberian Division (Russian Federation)

Epitaxial GaAs layers containing InAs semiconductor quantum dots and As metal quantum dots are grown by molecular beam epitaxy. The InAs quantum dots are formed by the Stranskii-Krastanow mechanism, whereas the As quantum dots are self-assembled in the GaAs layer grown at low temperature with a large As excess. The microstructure of the samples is studied by transmission electron microscopy. It is established that the As metal quantum dots formed in the immediate vicinity of the InAs semiconductor quantum dots are larger in size than the As quantum dots formed far from the InAs quantum dots. This is apparently due to the effect of strain fields of the InAs quantum dots upon the self-assembling of As quantum dots. Another phenomenon apparently associated with local strains around the InAs quantum dots is the formation of V-like defects (stacking faults) during the overgrowth of the InAs quantum dots with the GaAs layer by low-temperature molecular beam epitaxy. Such defects have a profound effect on the self-assembling of As quantum dots. Specifically, on high-temperature annealing needed for the formation of large-sized As quantum dots by Ostwald ripening, the V-like defects bring about the dissolution of the As quantum dots in the vicinity of the defects. In this case, excess arsenic most probably diffuses towards the open surface of the sample via the channels of accelerated diffusion in the planes of stacking faults.

• OSTI ID: 21562389
• Journal Information: Semiconductors, Vol. 43, Issue 12; Other Information: DOI: 10.1134/S1063782609120082; Copyright (c) 2009 Pleiades Publishing, Ltd.; ISSN 1063-7826
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANNEALING
ARSENIC
DEFECTS
DIFFUSION
DISSOLUTION
GALLIUM ARSENIDES
INDIUM ARSENIDES
LAYERS
METALS
MICROSTRUCTURE
MOLECULAR BEAM EPITAXY
QUANTUM DOTS
SEMICONDUCTOR MATERIALS
STACKING FAULTS
SURFACES
TEMPERATURE RANGE 0065-0273 K
TEMPERATURE RANGE 0400-1000 K
TRANSMISSION ELECTRON MICROSCOPY
ARSENIC COMPOUNDS
ARSENIDES
CRYSTAL DEFECTS
CRYSTAL GROWTH METHODS
CRYSTAL STRUCTURE
ELECTRON MICROSCOPY
ELEMENTS
EPITAXY
GALLIUM COMPOUNDS
HEAT TREATMENTS
INDIUM COMPOUNDS
MATERIALS
MICROSCOPY
NANOSTRUCTURES
PNICTIDES
SEMIMETALS
TEMPERATURE RANGE