Abstract
We present a systematic study of extended defect creation in InGaAs/GaAs multiple quantum well (MQW) structures. Three sets of samples, grown by molecular beam epitaxy, were characterized by high-resolution x-ray diffraction and transmission electron microscopy. First, in a temperature series, optimal deposition temperature of 505 °C was found for the In composition of 20% as determined from dislocation loop (DL) density and inspection of diffuse scattering patterns. InGaAs decomposition and lateral layer thickness undulations were observed above this optimal temperature. Second, increase of MQW periodicity from ×5 to ×10 revealed a thickness-related cumulative deterioration, characterized by increased likelihood of defect intersection with continued MQW growth, as suggested by an increase of the secondary DL density from ∼1.6×10<sup>7</sup> cm<sup>-2</sup> to ∼6×10<sup>8</sup> cm<sup>-2</sup>. Additional strained layers experienced an ever-degrading quality of the growth surface. Third, a set consisting of samples with three different MQW periods was investigated. Different stages, suggested by a model of defect creation, were obtained for these different MQW periods, allowing specification of particular type, density, and spatial distribution of extended defects for each stage of defect creation.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 43-48 |
| Number of pages | 6 |
| Journal | Journal of Crystal Growth |
| Volume | 425 |
| DOIs | |
| State | Published - Jul 28 2015 |
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Keywords
- A1. Defects
- A1. High resolution x-ray diffraction
- A1. Nanostructures
- A3. Molecular beam epitaxy
- A3. Superlattices
- B2. Indium gallium arsenide
ASJC Scopus subject areas
- Condensed Matter Physics
- Materials Chemistry
- Inorganic Chemistry
Cite this
Defect creation in InGaAs/GaAs multiple quantum wells-I. Structural properties. / Karow, Matthias M.; Faleev, Nikolai N.; Smith, David; Honsberg, Christiana.
In: Journal of Crystal Growth, Vol. 425, 28.07.2015, p. 43-48.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Defect creation in InGaAs/GaAs multiple quantum wells-I. Structural properties
AU - Karow, Matthias M.
AU - Faleev, Nikolai N.
AU - Smith, David
AU - Honsberg, Christiana
PY - 2015/7/28
Y1 - 2015/7/28
N2 - We present a systematic study of extended defect creation in InGaAs/GaAs multiple quantum well (MQW) structures. Three sets of samples, grown by molecular beam epitaxy, were characterized by high-resolution x-ray diffraction and transmission electron microscopy. First, in a temperature series, optimal deposition temperature of 505 °C was found for the In composition of 20% as determined from dislocation loop (DL) density and inspection of diffuse scattering patterns. InGaAs decomposition and lateral layer thickness undulations were observed above this optimal temperature. Second, increase of MQW periodicity from ×5 to ×10 revealed a thickness-related cumulative deterioration, characterized by increased likelihood of defect intersection with continued MQW growth, as suggested by an increase of the secondary DL density from ∼1.6×107 cm-2 to ∼6×108 cm-2. Additional strained layers experienced an ever-degrading quality of the growth surface. Third, a set consisting of samples with three different MQW periods was investigated. Different stages, suggested by a model of defect creation, were obtained for these different MQW periods, allowing specification of particular type, density, and spatial distribution of extended defects for each stage of defect creation.
AB - We present a systematic study of extended defect creation in InGaAs/GaAs multiple quantum well (MQW) structures. Three sets of samples, grown by molecular beam epitaxy, were characterized by high-resolution x-ray diffraction and transmission electron microscopy. First, in a temperature series, optimal deposition temperature of 505 °C was found for the In composition of 20% as determined from dislocation loop (DL) density and inspection of diffuse scattering patterns. InGaAs decomposition and lateral layer thickness undulations were observed above this optimal temperature. Second, increase of MQW periodicity from ×5 to ×10 revealed a thickness-related cumulative deterioration, characterized by increased likelihood of defect intersection with continued MQW growth, as suggested by an increase of the secondary DL density from ∼1.6×107 cm-2 to ∼6×108 cm-2. Additional strained layers experienced an ever-degrading quality of the growth surface. Third, a set consisting of samples with three different MQW periods was investigated. Different stages, suggested by a model of defect creation, were obtained for these different MQW periods, allowing specification of particular type, density, and spatial distribution of extended defects for each stage of defect creation.
KW - A1. Defects
KW - A1. High resolution x-ray diffraction
KW - A1. Nanostructures
KW - A3. Molecular beam epitaxy
KW - A3. Superlattices
KW - B2. Indium gallium arsenide
UR - http://www.scopus.com/inward/record.url?scp=84937852024&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84937852024&partnerID=8YFLogxK
U2 - 10.1016/j.jcrysgro.2015.03.051
DO - 10.1016/j.jcrysgro.2015.03.051
M3 - Article
AN - SCOPUS:84937852024
VL - 425
SP - 43
EP - 48
JO - Journal of Crystal Growth
JF - Journal of Crystal Growth
SN - 0022-0248
ER -