Morphologies of Self-Assembled Quantum Dots: A Variational Approach

MRS Proceedings ◽

10.1557/proc-696-n5.10 ◽

2001 ◽

Vol 696 ◽

Author(s):

R. Arief Budiman ◽

Harry E. Ruda

Keyword(s):

Quantum Dots ◽

External Field ◽

Layer Thickness ◽

Variational Approach ◽

3D Model ◽

Strain Tensor ◽

Wetting Layer ◽

Island Formation ◽

Strained Layer ◽

Equilibrium Shapes

AbstractWe construct a 3D model for coherent island formation by (i) using a novel 3D strain tensor to account for bulk strains and (ii) representing adatom di.usion as an external field that perturbs an otherwise. at strained layer. Equilibrium shapes of coherent islands and wetting layer thickness are obtained. Coherently compressed layers are typically unstable, but become stable in tension. Comparisons with Si1-xGex/Si(001) and Si0.5Ge0.5/Si1-xGex(001) layers are discussed.

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Morphologies of Self-Assembled Quantum Dots: A Variational Approach

MRS Proceedings ◽

10.1557/proc-707-n5.10.1 ◽

2001 ◽

Vol 707 ◽

Author(s):

R. Arief Budiman ◽

Harry E. Ruda

Keyword(s):

Quantum Dots ◽

External Field ◽

Layer Thickness ◽

Variational Approach ◽

3D Model ◽

Strain Tensor ◽

Wetting Layer ◽

Strained Layer ◽

Adatom Diffusion ◽

Equilibrium Shapes

ABSTRACTWe construct a 3D model for coherent island formation by (i) using a novel 3D strain tensor to account for bulk strains and (ii) representing adatom diffusion as an external field that perturbs an otherwise flat strained layer. Equilibrium shapes of coherent islands and wetting layer thickness are obtained. Coherently compressed layers are typically unstable, but become stable in tension. Comparisons with Si1-xGex/Si(001) and Si0.5Ge0.5/Si1-xGex(001) layers are discussed.

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Impact of the wetting layer thickness on the emission wavelength of direct band gap GeSn/Ge quantum dots

Materials Research Express ◽

10.1088/2053-1591/aa785b ◽

2017 ◽

Vol 4 (7) ◽

pp. 075026 ◽

Cited By ~ 3

Author(s):

Bouraoui Ilahi ◽

Reem Al-Saigh ◽

Bassem Salem

Keyword(s):

Quantum Dots ◽

Band Gap ◽

Layer Thickness ◽

Emission Wavelength ◽

Wetting Layer ◽

Direct Band Gap ◽

Direct Band ◽

Ge Quantum Dots

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Effects of a InGaAs Strained Layer on Structures and Photoluminescence Characteristics of InAs Quantum Dots

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.148-149.897 ◽

2010 ◽

Vol 148-149 ◽

pp. 897-902

Author(s):

Jian Ming Yao ◽

Ling Min Kong ◽

Shi Lai Wang

Keyword(s):

Quantum Dots ◽

Integral Intensity ◽

Wetting Layer ◽

Ingaas Layer ◽

Temperature Dependent ◽

Inas Quantum Dots ◽

Strained Layer ◽

Gaas Matrix ◽

Electronic Microscope ◽

Temperature Dependent Photoluminescence

The influences of a thin InGaAs layer grown on GaAs(100) substrate before deposited InAs self-assembled quantum dots(SAQDs) were experimentally investigated. Scanning electronic microscope (SEM) measurements show that the InGaAs strained layer may release the strain between wetting layer and QDs, and then enlarge size of QDs. When the thickness of InAs layer is small, the QDs are chained. Temperature dependent photoluminescence (TDPL) measurements show that the PL peaks of InAs QDs with In0.1Ga0.9As show much more red shift compared with the QDs directly deposited on GaAs matrix, and PL integral intensity enhances as T rises from 50K to 90K. We attribute this enhancement to the small potential barrier between WL and QDs produced by the InGaAs stained layer.

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Raman Scattering Study for Self-Organized Ge Quantum Dots Formed on Si Substrate

MRS Proceedings ◽

10.1557/proc-744-m2.11 ◽

2002 ◽

Vol 744 ◽

Author(s):

T. R. Yang ◽

M. M. Dvoynenko ◽

Z. C. Feng ◽

I. Ferguson ◽

H. H. Cheng

Keyword(s):

Quantum Dots ◽

Raman Spectroscopy ◽

Raman Scattering ◽

Layer Thickness ◽

Line Width ◽

Wetting Layer ◽

Si Substrate ◽

Spectroscopy Technique ◽

Self Organized ◽

Scattering Study

ABSTRACTA Raman scattering study for self-organized Ge dots on Si substrate is presented. Raman signals from the Ge islands and Si substrate have been separated, by means of difference Raman spectroscopy technique. The wetting layer thickness and strain were estimated from the line width and the position of the peak. The estimated wetting layer thickness values are comparative with the Ge dot height obtained from microscopy measurements. As explained, the strain is observed to decrease with an increase of the Ge island height and the wetting layer thickness.

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