Multiple stacking of self-assembled InAs quantum dots embedded by GaNAs strain compensating layers

Journal Article · Sun Oct 15 04:00:00 EDT 2006 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.2359623· OSTI ID:20884773

Oshima, Ryuji; Hashimoto, Takayuki; Shigekawa, Hidemi; Okada, Yoshitaka ^[1]

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1. Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573 (Japan)

We have investigated a growth technique to realize high-quality multiple stacking of self-assembled InAs quantum dots (QDs) on GaAs (001) substrates, in which GaN{sub x}As{sub 1-x} dilute nitride material was used as a strain compensation layer (SCL). The growth was achieved by atomic hydrogen-assisted rf molecular beam epitaxy, and the effect of strain compensation was systematically investigated by using high-resolution x-ray diffraction measurements. By controlling the net average lattice strain to a minimum by covering each QD layer with a 40-nm-thick GaN{sub 0.005}As{sub 0.995} SCL, we obtained a superior QD structure with no degradation in size homogeneity. Further, no dislocations were generated even after 30 layers of stacking, and the area density of QDs amounted to as high as 3x10{sup 12} cm{sup -2}. The photoluminescence peak linewidth was improved by about 22% for QDs embedded in GaNAs SCLs as the accumulation of lattice strain with increasing growth of QD layers was avoided, which would otherwise commonly lead to degradation of size homogeneity and generation of dislocations.

• OSTI ID: 20884773
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 8 Vol. 100; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CRYSTAL GROWTH
DISLOCATIONS
GALLIUM ARSENIDES
GALLIUM NITRIDES
HYDROGEN
INDIUM ARSENIDES
LAYERS
MOLECULAR BEAM EPITAXY
PHOTOLUMINESCENCE
QUANTUM DOTS
SEMICONDUCTOR MATERIALS
SUBSTRATES
X-RAY DIFFRACTION