Generalized Muller–Kern formula for equilibrium thickness of a wetting layer with respect to the dependence of the surface energy of island facets on the thickness of the 2D layer

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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Drying of solids wetted by thin liquid films

Canadian Journal of Physics ◽

10.1139/p90-151 ◽

1990 ◽

Vol 68 (9) ◽

pp. 1084-1088 ◽

Cited By ~ 312

Author(s):

F. Brochard Wyart ◽

J. Daillant

Keyword(s):

Molecular Size ◽

Liquid Films ◽

Nucleation And Growth ◽

Thin Liquid Films ◽

Wetting Layer ◽

Nonwetting Liquid ◽

Dry Patch ◽

Dry Spot ◽

Wetting Liquid ◽

Equilibrium Thickness

(i) A film of a nonwetting liquid is not stable. If it is thick (thickness e ≥ 1000 Å) it is metastable and evolves via nucleation and growth of a dry spot. If it is thin, it is unstable against spinodal decomposition (amplification of thermal undulations) and breaks into microscopic droplets of size ~e2/a (a = a molecular size), (ii) A film made with a wetting liquid is metastable and tends to shrink whenever e < eS (the equilibrium thickness of the wetting layer). Contrary to case (i) where the growth of a dry patch is controlled by capillary forces, the central role for drying in case (ii) is played by long-range forces, and the only process is nucleation and growth.

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On the free energy of nematic wetting layers

Canadian Journal of Chemistry ◽

10.1139/v88-094 ◽

1988 ◽

Vol 66 (4) ◽

pp. 553-556 ◽

Cited By ~ 16

Author(s):

Donald E. Sullivan ◽

Reinhard Lipowsky

Keyword(s):

Free Energy ◽

Layer Thickness ◽

Order Parameter ◽

Van Der Waals ◽

Van Der Waals Forces ◽

Wetting Layer ◽

Nematic Director ◽

The Mean ◽

Wetting Layers

The contributions to the free energy of a nematic wetting layer as a function of its thickness l are analyzed. The longest-range contribution is due to distortion of the nematic director across the film, resulting from different preferred molecular orientations at the two interfaces bounding the film. Van der Waals forces as well as the decaying tails of the interfacial order-parameter profiles yield contributions to the free energy of successively shorter range. These effects lead to crossovers between different scaling régimes for variation of the mean wetting-layer thickness with temperature. Experimental implications of the results are described.

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Temperature-dependent evolution of the wetting layer thickness during Ge deposition on Si(001)

Nanotechnology ◽

10.1088/0957-4484/22/28/285704 ◽

2011 ◽

Vol 22 (28) ◽

pp. 285704 ◽

Cited By ~ 13

Author(s):

R Bergamaschini ◽

M Brehm ◽

M Grydlik ◽

T Fromherz ◽

G Bauer ◽

...

Keyword(s):

Layer Thickness ◽

Wetting Layer ◽

Temperature Dependent

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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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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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