Features of two-dimensional to three-dimensional growth mode transition of Ge in SiGe/Si(001) heterostructures with strained layers

In vacuo deposition of ultrathin ionic liquid films combined with angle-resolved X-ray photoelectron spectroscopy demonstrates that the initial three-dimensional growth mode of [C2C1Im][OTf] deposited onto the bare Au(111) surface can be switched to two-dimensional growth by adding submonolayer amounts of Pd.

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Differences in The Growth Mechanism of InxGa1−xAs on GaAs Studied by The Electrical Properties of Al0.3Ga0.7As/InxGa1−xAs Heterostructures (0.2 ≤ × ≤ 0.4)

MRS Proceedings ◽

10.1557/proc-263-323 ◽

1992 ◽

Vol 263 ◽

Cited By ~ 1

Author(s):

T. Schweizer ◽

K. Köhler ◽

P. Ganser ◽

P. Hiesinger ◽

W. Rothemund

Keyword(s):

Electrical Properties ◽

Electron Mobility ◽

Three Dimensional ◽

Interface Roughness ◽

Growth Mode ◽

Misfit Dislocations ◽

Anisotropic Growth ◽

Two Dimensional ◽

Critical Layer Thickness ◽

Dimensional Growth

ABSTRACTLattice mismatched InxGa1−xAs layers with InAs mole fractions below 0.25 grow in a two dimensional growth mode on GaAs. If the thickness of these layers is beyond the critical layer thickness the strain relaxes through misfit dislocations. The misfit dislocation density in the <011> and <01-1> direction differs for n-type layers. This results in a highly anisotropic electron mobility for GaAs/InxGa1−xAs/Al0.3Ga0.7As inverted HEMT structures. A higher electron mobility in the < 011 > direction is measured in comparison to the <01-1> direction. The resistance ratio in the two perpendicular directions exceeds 105. For a three dimensional growth mode, the InxGa1−xAs layer shows interface roughness which degrades the transport properties of the normal Al0.3Ga0.7As/ InxGa1−xAs/ GaAs HEMT structures more than the inverted GaAs/InxGa1−xAs/ Al0.3Ga0.7As HEMT structures. For a three dimensional growth mode, an anisotropic electron mobility for Al0.3Ga0.7As/InxGal, As/GaAs HEMT structures is also observed. For these structures the highest electron mobility is measured in the < 01-1 > direction. This anisotropy could be explained by anisotropic growth rates in the <011> and < 01-1 > directions which results in growth islands with asymmetric extensions.

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Growth Evolution of (Zn,Cd)Se Quantum Dots Deduced from Spatially Resolved Structural and Optical Characterization

MRS Proceedings ◽

10.1557/proc-571-325 ◽

1999 ◽

Vol 571 ◽

Cited By ~ 1

Author(s):

K. Leonard ◽

D. Hommel ◽

A. Stockmann ◽

H. Selke ◽

J. Seufert ◽

...

Keyword(s):

Quantum Dots ◽

Quantum Wells ◽

Three Dimensional ◽

High Energy ◽

Growth Direction ◽

Growth Mode ◽

Gradual Transition ◽

Mode Transition ◽

Spatially Resolved ◽

Composition Fluctuations

ABSTRACTThe growth mode of CdSe layers grown by migration enhanced epitaxy between ZnSe barriers has been investigated. In situ reflection high-energy electron diffraction shows a gradual transition to a three-dimensional growth mode which, however, is not accompanied by a change of the surface lattice constant. High-resolution transmission electron micrographs reveal a strong Cd diffusion, leading to ternary ZnCdSe quantum wells. Furthermore. composition fluctuations perpendicular to the growth direction on a nanometer scale are found already prior to the beginning of the growth mode transition. In the case of heterostructures containing a CdSe layer that has undergone the growth mode transition, micrographs show Cd-rich quantum dots with diameters of around 8 nm and heights of around 1.5 nm within a ternary quantum well. By spatially resolved photoluminescence the emission from single quantum dots could be observed. The polarization dependence of the emission from single dots indicates an asymmetric shape of the dots with certain preferential orientations along the [110] and [110] directions.

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GaSb layers with low defect density deposited on (001) GaAs substrate in two-dimensional growth mode using molecular beam epitaxy

Current Applied Physics ◽

10.1016/j.cap.2019.02.012 ◽

2019 ◽

Vol 19 (4) ◽

pp. 542-547

Author(s):

Agata Jasik ◽

Iwona Sankowska ◽

Andrzej Wawro ◽

Jacek Ratajczak ◽

Dariusz Smoczyński ◽

...

Keyword(s):

Molecular Beam Epitaxy ◽

Gaas Substrate ◽

Molecular Beam ◽

Defect Density ◽

Growth Mode ◽

Two Dimensional ◽

Dimensional Growth

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A RHEED Study of MBE Growth of ZnSe on GaAs (111) A-(2 × 2)

Surface Review and Letters ◽

10.1142/s0218625x03005384 ◽

2003 ◽

Vol 10 (04) ◽

pp. 669-675

Author(s):

F. S. Gard ◽

J. D. Riley ◽

R. Leckey ◽

B. F. Usher

Keyword(s):

Growth Rate ◽

Electron Diffraction ◽

Substrate Temperature ◽

Three Dimensional ◽

High Energy ◽

Growth Mode ◽

Two Dimensional ◽

High Energy Electron ◽

Mbe Growth ◽

Atomic Flux

ZnSe epilayers have been grown under various Se/Zn atomic flux ratios in the range of 0.22–2.45 at a substrate temperature of 350°C on Zn pre-exposed GaAs (111) A surfaces. Real time reflection high energy electron diffraction (RHEED) observations have shown a transition from a two-dimensional (2D) to a three-dimensional (3D) growth mode. The transition time depends directly upon the growth rate. A detailed discussion is presented to explore the cause of this change in the growth mode.

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Crystallization Time Dependence of Nanohybrid Shish-Kebab Structure in HDPE/PA66 Nanofibers Composites via Solution Crystallization

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.110-116.3786 ◽

2011 ◽

Vol 110-116 ◽

pp. 3786-3790

Author(s):

Wen Juan Han ◽

Guo Qiang Zheng ◽

Yan Yan Liang ◽

Chun Tai Liu ◽

Chang Yu Shen

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Time Dependence ◽

Isothermal Crystallization ◽

Three Dimensional ◽

Crystallization Time ◽

Two Dimensional ◽

Solution Crystallization ◽

Dimensional Growth ◽

Scanning Electron

In this study, PA66 nanofibers were successfully solution electrospun. The crystalline morphological features of HDPE solution induced by nanofibers were investigated by scanning electron microscopy (SEM). Nanohybrid shish-kebab (NHSK) can be formed in HDPE solution via isothermal crystallization, in which PA66 nanofibers serve as shish and HDPE lamellae act as kebabs surrounding the nanofibers periodically. Additionally, crystallization time has significant effect on the structure of HDPE kebab in NHSK, i.e., as crystallization time increases, the size of the kebab increases and the crystals decorated on PA66 nanofibers exhibit a three-dimensional growth (i.e., aggregate of crystallites) rather than a two-dimensional one (i.e., disc-like lamellae normal to the axis of nanofiber).

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