Growth mode transition to pyramid from layer by layer of heteroepitaxial PbTiO3 islands on a (001) vicinal SrTiO3 substrate fabricated by hydrothermal epitaxy

AbstractMetastable solid-solutions in the MgO-CaO system grow readily on MgO at 300°C by molecular beam epitaxy. We observe RHEED oscillations indicating a layer-by-layer growth mode; in-plane orientation can be described by the Matthews theory of island rotations. Although some films start to unmix at 500°C, others have been observed to be stable up to 900°C. The Mgl-xCaxO solid solutions grow despite a larger miscibility gap in this system than in any system for which epitaxial solid solutions have been grown. We describe attempts to use these materials as adjustable-lattice constant epitaxial building blocks

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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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Initial Growth and Crystallization Onset of Plasma Enhanced-Atomic Layer Deposited ZnO

Crystals ◽

10.3390/cryst10040291 ◽

2020 ◽

Vol 10 (4) ◽

pp. 291

Author(s):

Alberto Perrotta ◽

Julian Pilz ◽

Roland Resel ◽

Oliver Werzer ◽

Anna Maria Coclite

Keyword(s):

Atomic Layer ◽

Layer Growth ◽

Growth Mode ◽

Ex Situ ◽

Native Oxide ◽

Layer By Layer ◽

Initial Growth ◽

Island Growth ◽

X Ray ◽

Crystallization Onset

Direct plasma enhanced-atomic layer deposition (PE-ALD) is adopted for the growth of ZnO on c-Si with native oxide at room temperature. The initial stages of growth both in terms of thickness evolution and crystallization onset are followed ex-situ by a combination of spectroscopic ellipsometry and X-ray based techniques (diffraction, reflectivity, and fluorescence). Differently from the growth mode usually reported for thermal ALD ZnO (i.e., substrate-inhibited island growth), the effect of plasma surface activation resulted in a substrate-enhanced island growth. A transient region of accelerated island formation was found within the first 2 nm of deposition, resulting in the growth of amorphous ZnO as witnessed with grazing incidence X-ray diffraction. After the islands coalesced and a continuous layer formed, the first crystallites were found to grow, starting the layer-by-layer growth mode. High-temperature ALD ZnO layers were also investigated in terms of crystallization onset, showing that layers are amorphous up to a thickness of 3 nm, irrespective of the deposition temperature and growth orientation.

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Surfactant-Mediated Epitaxial Growth of Metallic Thin Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.117.55 ◽

2010 ◽

Vol 117 ◽

pp. 55-61

Author(s):

Masao Kamiko ◽

Ryoichi Yamamoto

Keyword(s):

Thin Film ◽

Thin Films ◽

Epitaxial Growth ◽

Film Growth ◽

Thin Film Growth ◽

Growth Mode ◽

Metallic Thin Films ◽

Layer By Layer ◽

Metallic Films ◽

Heteroepitaxial Growth

The effects of several surfactants on the homoepitaxial and heteroepitaxial growth of metallic films and multilayers have been studied and compared. Our measurements clearly revealed that pre-deposition of a small amount of surfactant prior to the adatom deposition changed thin film growth mode and structure. The pre-deposited surfactant enhanced layer-by-layer (LBL) growth of the homoepitaxial and heteroepitaxial growth of metallic films. The surfactant also enhanced the epitaxial growth of metallic multilayer.

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