Surfactant-Mediated Growth of Ge/Si(001) Interface Studied by XPD

The influence of Sb as a surfactant on the formation of Si/Ge interface is studied by means of XPD (X-ray photoelectron diffraction) and AED (Auger electron diffraction) from Ge and Si core levels. The technique employed is particularly suitable for checking the film tetragonal distortion, the growth morphology and the sharpness of the interface. We found a layer by layer growth mode for 3 ML of Ge on Si(001) and related values of strain of the film close to the value predicted by the elastic theory which enforces the use of such a surfactant to obtain high quality and sharp heterostructures. In addition, studying the influence of 3 ML of the Si cap layer on the 3 ML Ge, we obtain no indication of Ge segregation into the Si cap layer. Finally, evidences of quality degradation after high temperature (T > 600° C ) annealing are shown.

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Growth twins in Bi2Ca1Sr2Cu2O8 superconductor single crystals

Journal of Materials Research ◽

10.1557/jmr.1990.0909 ◽

1990 ◽

Vol 5 (5) ◽

pp. 909-912 ◽

Cited By ~ 7

Author(s):

P. D. Han ◽

A. Asthana ◽

Z. Xu ◽

D. A. Payne

Keyword(s):

Electron Microscopy ◽

Crystal Growth ◽

Large Scale ◽

Layer Growth ◽

Layer By Layer ◽

X Ray Diffraction ◽

Growth Morphology ◽

X Ray ◽

Twin Formation ◽

First Time

Large-scale twin structures in single crystal Bi2Ca1Sr2Cu2O8 (2122) are reported for the first time. Symmetrical 90° (i.e., a-b) twins with a [110] type twin boundary were observed. A characteristic layer-growth morphology and jagged twin walls suggest that twin formation occurred layer by layer during crystal growth; i.e., the twins were growth twins. Hot-stage optical microscopy, x-ray diffraction, and electron microscopy results are discussed with reference to twin morphology.

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X-Ray Photoelectron and Auger Electron Forward-Scattering Studies of the Epitaxial Growth of Fe on Ag(100).

MRS Proceedings ◽

10.1557/proc-229-27 ◽

1991 ◽

Vol 229 ◽

Cited By ~ 12

Author(s):

William F. Egelhoff

Keyword(s):

Electron Diffraction ◽

Auger Electron ◽

High Energy ◽

Layer Growth ◽

Forward Scattering ◽

Energy Electron ◽

Atomic Step ◽

Layer By Layer ◽

X Ray ◽

Place Exchange

AbstractA controversy has arisen in the past year over whether or not the growth of Fe on Ag(100) at room temperature occurs by a layer-by-layer mechanism. The present work attempts to address this controversy with an investigation of the issues, primarily by x-ray photoelectron (XPS) and Auger electron forward scattering, but with important supporting data from low-energy electron diffraction (LEED), and reflection high-energy electron diffraction (RHEED) oscillations. The results of this work suggest that the origin of the controversy lies in different substrate preparation techniques which produce different atomic step densities on the Ag(100) surface. The step sites are implicated as being the initiators of major departures from a layer-by-layer growth mode whenever most of the deposited Fe atoms have sufficient mobility to reach these steps. However, even when the Fe atoms cannot reach these steps it appears that atomic place-exchange occurs with ≥25% of the top-layer Ag atoms. Atomic place-exchange mechanisms, which could account for this intermixing, have been observed in recent molecular-dynamics simulations of epitakial growth. Thus it seems probable that under the conditions that appear to produce layer-by-layer growth, the growth begins as layer-by-layer growth of an FeAg alloy, and only becomes layer-by-layer in pure Fe as the segregating Ag atoms gradually get left behind in the growing Fe film.

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Kinetic Control of CaF2 on Si(111) Growth Morphology

MRS Proceedings ◽

10.1557/proc-312-207 ◽

1993 ◽

Vol 312 ◽

Author(s):

J. D. Denlinger ◽

Eli Rotenberg ◽

U. Hessingert ◽

M. Leskovar ◽

Marjorie A. Olmstead

Keyword(s):

Photoelectron Spectroscopy ◽

Molecular Beam ◽

Layer Growth ◽

Layer By Layer ◽

X Ray ◽

Photoelectron Diffraction ◽

Triple Layer ◽

Growth Modes ◽

Level Shifts

AbstractThin (0.5 to 8 triple layer) CaF2 on Si(111) films were grown using molecular beam epitaxy (MBE) and characterized using an in situ combination of x-ray photoelectron spectroscopy (XPS) and componentresolved x-ray photoelectron diffraction (XPD). We identified surface, bulk-like, and interface F and Ca core-level shifts and used the XPS shifts and XPD modulations to identify the growth modes as a function of the kinetic parameters of CaF2 flux and Si temperature. We identify 3 distinct regimes: (i) for high temperatures and flux we find a complete reacted F-Ca-Si layer, overlaid by 2 layer high islands which coalesce, followed by layer-by-layer growth, (ii) for high temperature and low flux, we find the reacted F-Ca-Si layer to be partially covered with thick islands, and (iii) for low temperatures we find an incompletely occupied F-Ca-Si layer followed by layer-by-layer growth. In all cases we find the buried interface to be structurally identical to the unburied F-Ca-Si layer

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NEAR EDGE X-RAY ABSORPTION AND X-RAY PHOTOELECTRON DIFFRACTION STUDIES OF THE STRUCTURAL ENVIRONMENT OF Ge–Si SYSTEMS

Surface Review and Letters ◽

10.1142/s0218625x00000282 ◽

2000 ◽

Vol 07 (03) ◽

pp. 307-331 ◽

Cited By ~ 3

Author(s):

P. CASTRUCCI ◽

R. GUNNELLA ◽

N. PINTO ◽

R. BERNARDINI ◽

M. DE CRESCENZI ◽

...

Keyword(s):

Electron Diffraction ◽

Room Temperature ◽

Layer Growth ◽

Silicon Substrates ◽

Layer By Layer ◽

X Ray ◽

Photoelectron Diffraction ◽

Structural Environment ◽

Structural And Electronic Properties ◽

X Ray Absorption

Near edge X-ray absorption spectroscopy (XAS), X-ray photoelectron diffraction (XPD) and Auger electron diffraction (AED) are powerful techniques for the qualitative study of the structural and electronic properties of several systems. The recent development of a multiple scattering approach to simulating experimental spectra opened a friendly way to the study of structural environments of solids and surfaces. This article reviews recent X-ray absorption experiments using synchrotron radiation which were performed at Ge L edges and core level electron diffraction measurements obtained using a traditional X-ray source from Ge core levels for ultrathin Ge films deposited on silicon substrates. Thermodynamics and surface reconstruction have been found to play a crucial role in the first stages of Ge growth on Si(001) and Si(111) surfaces. Both techniques show the occurrence of intermixing processes even for room-temperature-grown Ge/Si(001) samples and give a straightforward measurement of the overlayer tetragonal distortion. The effects of Sb as a surfactant on the Ge/Si(001) interface have also been investigated. In this case, evidence of layer-by-layer growth of the fully strained Ge overlayer with a reduced intermixing is obtained when one monolayer of Sb is predeposited on the surface.

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High-Quality AlN by Initial Layer-by-Layer Growth on Surface-Controlled 4H-SiC(0001) Substrate

Japanese Journal of Applied Physics ◽

10.1143/jjap.42.l445 ◽

2003 ◽

Vol 42 (Part 2, No. 5A) ◽

pp. L445-L447 ◽

Cited By ~ 40

Author(s):

Norio Onojima ◽

Jun Suda ◽

Hiroyuki Matsunami

Keyword(s):

Layer Growth ◽

Layer By Layer ◽

High Quality ◽

Initial Layer

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Synthesis and Characterization of Zn Oxide Hexagonal Nano-Pole Films on Quartz Glass Substrate

International Journal of Chemical Reactor Engineering ◽

10.2202/1542-6580.2051 ◽

2009 ◽

Vol 7 (1) ◽

Author(s):

Jie Chen ◽

Jun Wang

Keyword(s):

Growth Mechanism ◽

Quartz Glass ◽

Photoelectron Spectroscopy ◽

Glass Substrate ◽

Sol Gel ◽

Layer Growth ◽

Layer By Layer ◽

Quartz Glass Substrate ◽

Wurtzite Phase ◽

X Ray

Hexagon-shaped Zn oxide nano-pole films with terraces and steps have been successfully fabricated by means of a combined approach involving sol-gel process, high-temperature heat treatment, and the hydrothermal method. The surface chemistry and morphological features of the films were characterized by means of x-ray photoelectron spectroscopy and scanning electron microcopy. All the diffraction peaks in x-ray diffraction pattern match with those of the hexagonal wurtzite phase of Zn oxide. Transmittance measurements show that the optical transmittance of the sample synthesized at 520°C on quartz glass substrate is the highest, reaching about 65% in the visible-light region. Based on the detailed structural characterization and the nucleation-growth kinetics, we find that the whole crystallization process of wurtzite Zn oxide nano-poles includes nanocatalysis and layer-by-layer growth mechanism. The present study provides an important understanding of the growth mechanism for nano-pole synthesis of Zn oxide and related materials.

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Four-inch high quality crack-free AlN layer grown on a high-temperature annealed AlN template by MOCVD

Journal of Semiconductors ◽

10.1088/1674-4926/42/12/122804 ◽

2021 ◽

Vol 42 (12) ◽

pp. 122804

Author(s):

Shangfeng Liu ◽

Ye Yuan ◽

Shanshan Sheng ◽

Tao Wang ◽

Jin Zhang ◽

...

Keyword(s):

High Temperature ◽

Vapor Deposition ◽

Physical Vapor Deposition ◽

Flat Surface ◽

Epitaxial Lateral Overgrowth ◽

High Temperature Annealing ◽

High Quality ◽

High Crystalline Quality ◽

X Ray ◽

Lateral Overgrowth

Abstract In this work, based on physical vapor deposition and high-temperature annealing (HTA), the 4-inch crack-free high-quality AlN template is initialized. Benefiting from the crystal recrystallization during the HTA process, the FWHMs of X-ray rocking curves for (002) and (102) planes are encouragingly decreased to 62 and 282 arcsec, respectively. On such an AlN template, an ultra-thin AlN with a thickness of ~700 nm grown by MOCVD shows good quality, thus avoiding the epitaxial lateral overgrowth (ELOG) process in which 3–4 μm AlN is essential to obtain the flat surface and high crystalline quality. The 4-inch scaled wafer provides an avenue to match UVC-LED with the fabrication process of traditional GaN-based blue LED, therefore significantly improving yields and decreasing cost.

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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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Growth of CaFeOX/LaFeO3 Superlattice on SrTiO3(100) Substrates

MRS Proceedings ◽

10.1557/opl.2011.245 ◽

2011 ◽

Vol 1292 ◽

Cited By ~ 3

Author(s):

Nobuyuki Iwata ◽

Mark Huijben ◽

Guus Rijnders ◽

Hiroshi Yamamoto ◽

Dave H. A. Blank

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Pulsed Laser ◽

Layer Growth ◽

Laser Deposition ◽

Growth Mode ◽

Layer By Layer ◽

X Ray Diffraction ◽

Reciprocal Space Mapping ◽

X Ray

ABSTRACTThe CaFeOX(CFO) and LaFeO3(LFO) thin films as well as superlattices were fabricated on SrTiO3(100) substrates by pulsed laser deposition (PLD) method. The tetragonal LFO film grew with layer-by-layer growth mode until approximately 40 layers. In the case of CFO, initial three layers showed layer-by-layer growth, and afterward the growth mode was transferred to two layers-by-two layers (TLTL) growth mode. The RHEED oscillation was observed until the end of the growth, approximately 50nm. Orthorhombic twin CaFeO2.5 (CFO2.5) structure was obtained. However, it is expected that the initial three CFO layers are CaFeO3 (CFO3) with the valence of Fe4+. The CFO and LFO superlattice showed a step-terraces surface, and the superlattice satellite peaks in a 2θ-θ and reciprocal space mapping (RSM) x-ray diffraction (XRD) measurements, indicating that the clear interfaces were fabricated.

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