Aspect ratio of liquid phase epitaxial SiGe∕Si(001) islands as probed by high resolution x-ray diffraction

ABSTRACTX-ray diffraction has been used to study the mask-induced strain in GaAs layers grown by the liquid phase epitaxial lateral overgrowth (ELO) on (100) GaAs substrates. SiO2 mask has been investigated to produce seeding areas for the ELO growth. It has been found that SiO2 attracts the ELO layers, which leads to their pronounced bending towards the oxide film and to the appearance of vertical strain in laterally grown parts of ELO. When SiO2 is removed by selective etching this strain disappears. We show evidence that the bending of ELO layers is reduced when the density of substrate dislocations is increased. This is explained as being due to enhancement of the initial vertical growth rate by dislocations supplying steps on the upper surface of ELO.

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High Tc Superconductor Films Grown by the Liquid Phase Epitaxial Technique

MRS Proceedings ◽

10.1557/proc-169-723 ◽

1989 ◽

Vol 169 ◽

Cited By ~ 3

Author(s):

C. S. Yang ◽

A. S. Yue

Keyword(s):

Liquid Phase ◽

Cross Sections ◽

X Ray Diffraction ◽

High Tc ◽

Liquid Phase Epitaxial ◽

X Ray ◽

Diffraction Patterns ◽

High Degree ◽

Superconductor Films

AbstractHigh Tc superconducting YBa2Cu3O7 films have been prepared by the Liquid Phase Epitaxial (LPE) technique. The x‐ray diffraction patterns displayed a high degree of (00l) preferred orientations with c‐axes perpendicular to the film surfaces. The in‐situ grown YBa2Cu3O7 films showed zero‐resistivity at 76*K. Examination of the film cross sections by SEM revealed a growth mechanism.

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Studies on high resolution x-ray diffraction, optical and transport properties of InAsxSb1−x∕GaAs (x⩽0.06) heterostructure grown using liquid phase epitaxy

Journal of Applied Physics ◽

10.1063/1.1784620 ◽

2004 ◽

Vol 96 (9) ◽

pp. 4989-4997 ◽

Cited By ~ 19

Author(s):

V. K. Dixit ◽

Bhavtosh Bansal ◽

V. Venkataraman ◽

H. L. Bhat ◽

K. S. Chandrasekharan ◽

...

Keyword(s):

Liquid Phase ◽

High Resolution ◽

Transport Properties ◽

Liquid Phase Epitaxy ◽

X Ray Diffraction ◽

X Ray

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A High Resolution Study of G.P. Zones in Aluminum - 4.2 at % Silver

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055904 ◽

1982 ◽

Vol 40 ◽

pp. 722-723 ◽

Cited By ~ 1

Author(s):

R. Gronsky

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

High Resolution ◽

Computer Simulations ◽

Structural Characteristics ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Resolution Study

The phenomenon of clustering in Al-Ag alloys has been extensively studied since the early work of Guinierl, wherein the pre-precipitation state was characterized as an assembly of spherical, ordered, silver-rich G.P. zones. Subsequent x-ray and TEM investigations yielded results in general agreement with this model. However, serious discrepancies were later revealed by the detailed x-ray diffraction - based computer simulations of Gragg and Cohen, i.e., the silver-rich clusters were instead octahedral in shape and fully disordered, atleast below 170°C. The object of the present investigation is to examine directly the structural characteristics of G.P. zones in Al-Ag by high resolution transmission electron microscopy.

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Tubulin structure at intermediate resolution

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100140634 ◽

1995 ◽

Vol 53 ◽

pp. 852-853

Author(s):

K. H. Downing ◽

S. G. Wolf ◽

E. Nogales

Keyword(s):

High Resolution ◽

Structural Data ◽

Therapeutic Drug ◽

Zinc Ions ◽

Two Dimensional ◽

X Ray Diffraction ◽

X Ray ◽

Negative Stain ◽

Functional Mechanisms ◽

Tubulin Structure

Microtubules are involved in a host of critical cell activities, many of which involve transport of organelles through the cell. Different sets of microtubules appear to form during the cell cycle for different functions. Knowledge of the structure of tubulin will be necessary in order to understand the various functional mechanisms of microtubule assemble, disassembly, and interaction with other molecules, but tubulin has so far resisted crystallization for x-ray diffraction studies. Fortuitously, in the presence of zinc ions, tubulin also forms two-dimensional, crystalline sheets that are ideally suited for study by electron microscopy. We have refined procedures for forming the sheets and preparing them for EM, and have been able to obtain high-resolution structural data that sheds light on the formation and stabilization of microtubules, and even the interaction with a therapeutic drug.Tubulin sheets had been extensively studied in negative stain, demonstrating that the same protofilament structure was formed in the sheets and microtubules. For high resolution studies, we have found that the sheets embedded in either glucose or tannin diffract to around 3 Å.

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High-resolution X-ray diffraction in crystalline structures with quantum dots

Uspekhi Fizicheskih Nauk ◽

10.3367/ufnr.0185.201505a.0449 ◽

2015 ◽

Vol 185 (5) ◽

pp. 449-478

Author(s):

Vasilii I. Punegov

Keyword(s):

Quantum Dots ◽

High Resolution ◽

X Ray Diffraction ◽

X Ray ◽

Crystalline Structures

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Synthesis and Na+ Ion Conductivity of Stoichiometric Na3Zr2Si2PO12 by Liquid-Phase Sintering with NaPO3 Glass

Materials ◽

10.3390/ma14143790 ◽

2021 ◽

Vol 14 (14) ◽

pp. 3790

Author(s):

Yongzheng Ji ◽

Tsuyoshi Honma ◽

Takayuki Komatsu

Keyword(s):

Solid State ◽

Liquid Phase ◽

Sintering Temperature ◽

Liquid Phase Sintering ◽

Ion Conductivity ◽

X Ray Diffraction ◽

Conventional Solid State Reaction ◽

X Ray ◽

Sintering Time ◽

Lower Activation

Sodium super ionic conductor (NASICON)-type Na3Zr2Si2PO12 (NZSP) with the advantages of the high ionic conductivity, stability and safety is one of the most famous solid-state electrolytes. NZSP, however, requires the high sintering temperature about 1200 °C and long sintering time in the conventional solid-state reaction (SSR) method. In this study, the liquid-phase sintering (LPS) method was applied to synthesize NZSP with the use of NaPO3 glass with a low glass transition temperature of 292 °C. The formation of NZSP was confirmed by X-ray diffraction analyses in the samples obtained by the LPS method for the mixture of Na2ZrSi2O7, ZrO2, and NaPO3 glass. The sample sintered at 1000 °C for 10 h exhibited a higher Na+ ion conductivity of 1.81 mS/cm at 100 °C and a lower activation energy of 0.18 eV compared with the samples prepared by the SSR method. It is proposed that a new LPE method is effective for the synthesis of NZSP and the NaPO3 glass has a great contribution to the Na+ diffusion at the grain boundaries.

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Transient liquid phase bonding of Cu and Al using metallic particles interlayers

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405420988235 ◽

2021 ◽

pp. 095440542098823

Author(s):

Alireza Zaheri ◽

Mohammadreza Farahani ◽

Alireza Sadeghi ◽

Naser Souri

Keyword(s):

Liquid Phase ◽

Mechanical Test ◽

Transient Liquid Phase ◽

Transient Liquid Phase Bonding ◽

Joint Interface ◽

Test Results ◽

X Ray Diffraction ◽

X Ray ◽

Metallic Particles ◽

Powder Interlayer

The bonding strength, and microstructures of Cu and Al couples using metallic powders as interlayer during transient liquid phase bonding (TLP bonding) were investigated. The interfacial morphologies and microstructures were studied by scanning electron microscopy equipped with energy dispersive X-ray spectroscopy, and X-ray diffraction. First, to explore the optimum bonding time and temperature, nine samples were bonded without interlayers in a vacuum condition. Mechanical test results indicated that bonding at 560°C in 20 min returns the highest bond strength (84% of Al). This bonding condition was used to join ten samples with powder interlayers. Powders were prepared by mixing different combinations of Cu, Al (+Fe nanoparticles) and Zn. In the bonding zone, different Cu9Al4, CuAl, and CuAl2 intermetallic co-precipitate. The strongest bonding is formed in the sample with the 70Al (+Fe)-30Cu powder interlayer. Powder interlayers present thinner and more uniform intermetallic layers at the joint interface.

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Dislocation Arrangement in a Thick LEO GaN Film on Sapphire

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300004130 ◽

2000 ◽

Vol 5 (S1) ◽

pp. 97-103

Author(s):

Kathleen A. Dunn ◽

Susan E. Babcock ◽

Donald S. Stone ◽

Richard J. Matyi ◽

Ling Zhang ◽

...

Keyword(s):

High Resolution ◽

Electron Diffraction ◽

Threading Dislocations ◽

X Ray Diffraction ◽

Burgers Vector ◽

X Ray ◽

The Third ◽

Dislocation Arrangement ◽

Image Position ◽

Gan Film

Diffraction-contrast TEM, focused probe electron diffraction, and high-resolution X-ray diffraction were used to characterize the dislocation arrangements in a 16µm thick coalesced GaN film grown by MOVPE LEO. As is commonly observed, the threading dislocations that are duplicated from the template above the window bend toward (0001). At the coalescence plane they bend back to lie along [0001] and thread to the surface. In addition, three other sets of dislocations were observed. The first set consists of a wall of parallel dislocations lying in the coalescence plane and nearly parallel to the substrate, with Burgers vector (b) in the (0001) plane. The second set is comprised of rectangular loops with b = 1/3 [110] (perpendicular to the coalescence boundary) which originate in the coalescence boundary and extend laterally into the film on the (100). The third set of dislocations threads laterally through the film along the [100] bar axis with 1/3<110>-type Burgers vectors These sets result in a dislocation density of ∼109 cm−2. High resolution X-ray reciprocal space maps indicate wing tilt of ∼0.5º.

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