X-Ray Diffraction Study of a Thin GaAs Film on Si(100)

ABSTRACTA 900A single crystalline GaAs film deposited by molecular beam epitaxy (MBE) on a silicon crystal cut 4.1° from (001) surface was characterized with X-ray diffraction measurements of the mosaic spread, particle size and strain distribution, and lattice parameter. The GaAs film had a larger mosaic spread in the direction of the steps of the silicon surface and coherent particle sizes of about 900 Å compared to the estimated film thickness of approximately 1000 Å. Superlattice reflections gave an ordered domain size of about 330 Å. There is a residual strain gradient in the film which is nearly linear with the lattice constant differing by about 0.044 Å between the surface of the film and its interface with the silicon substrate. Lattice parameter measurements indicate a small expansion of 0.13% perpendicular to the plane of the film.

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Grazing-incidence X-ray diffraction of single GaAs nanowires at locations defined by focused ion beams

Journal of Applied Crystallography ◽

10.1107/s0021889813004226 ◽

2013 ◽

Vol 46 (4) ◽

pp. 887-892 ◽

Cited By ~ 4

Author(s):

Genziana Bussone ◽

Rüdiger Schott ◽

Andreas Biermanns ◽

Anton Davydok ◽

Dirk Reuter ◽

...

Keyword(s):

Gaas Substrate ◽

Lattice Spacing ◽

Molecular Beam ◽

Grazing Incidence ◽

Lattice Parameter ◽

Ion Beams ◽

Focused Ion Beams ◽

X Ray Diffraction ◽

X Ray ◽

Gaas Nanowires

Grazing-incidence X-ray diffraction measurements on single GaAs nanowires (NWs) grown on a (111)-oriented GaAs substrate by molecular beam epitaxy are reported. The positions of the NWs are intentionally determined by a direct implantation of Au with focused ion beams. This controlled arrangement in combination with a nanofocused X-ray beam allows the in-plane lattice parameter of single NWs to be probed, which is not possible for randomly grown NWs. Reciprocal space maps were collected at different heights along the NW to investigate the crystal structure. Simultaneously, substrate areas with different distances from the Au-implantation spots below the NWs were probed. Around the NWs, the data revealed a 0.4% decrease in the lattice spacing in the substrate compared with the expected unstrained value. This suggests the presence of a compressed region due to Au implantation.

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Investigation Of Helium Implanted Fe–Cr Alloys By Means Of X–Ray Diffraction And Positron Annihilation Spectroscopy

Journal of Electrical Engineering ◽

10.2478/jee-2015-0055 ◽

2015 ◽

Vol 66 (6) ◽

pp. 334-338

Author(s):

Patrik Novák ◽

Aleksandr Gokhman ◽

Edmund Dobročka ◽

Jozef Bokor ◽

Stanislav Pecko

Keyword(s):

Positron Annihilation ◽

Domain Size ◽

Surface Region ◽

Grazing Incidence ◽

Positron Annihilation Spectroscopy ◽

Lattice Parameter ◽

Implantation Dose ◽

X Ray Diffraction ◽

Coherent Domain Size ◽

X Ray

Abstract X-ray diffraction (XRD) and positron annihilation spectroscopy (PAS) have been used for the characterization of the two binary alloys Fe-Cr with Cr content 2.36 and 8.39 wt%. The influence of ion implantation on these alloys was studied. Different implantation doses of helium, up to 0.5 C/cm2, were used to simulate neutron-induced damage in a sub-surface region. To characterize the damage, a lattice parameter, coherent domain size, residual stress and a crystallographic texture have been studied by grazing incidence X-ray diffraction (GIXRD). It was found out that these parameters showed a similar dependence on the implantation dose as the positron lifetime determined by positron annihilation spectroscopy.

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Shape-fitting analyses of two-dimensional X-ray diffraction spots for strain-distribution evaluation in a β-FeSi2 nanofilm

Journal of Applied Crystallography ◽

10.1107/s1600576719007234 ◽

2019 ◽

Vol 52 (4) ◽

pp. 732-744 ◽

Cited By ~ 1

Author(s):

Shohei Takemoto ◽

Ken Hattori ◽

Masaaki Someta ◽

Azusa N. Hattori ◽

Hidekazu Tanaka ◽

...

Keyword(s):

Strain Distribution ◽

Domain Size ◽

Grazing Incidence ◽

X Ray Diffraction ◽

X Ray ◽

Shape Fitting ◽

Transmission Electron ◽

Minimum Residual ◽

Strain Components ◽

Homogeneous Domains

New fitting analyses for peak shapes in a 2D reciprocal-space map are demonstrated to evaluate the strain, strain distribution and domain size of a crystalline ultra-thin (15 Å) film of β-FeSi2(100) grown epitaxially on an Si(001) substrate, using grazing-incidence X-ray diffraction. A 2D Laue-fit analysis taking into account instrument broadening and the double-domain effect provides residual maps as a function of the inequivalent strains ∊ b and ∊ c along the b and c axes of β-FeSi2, respectively (and domain size D), reflecting the probability of existence of homogeneous domains with fixed ∊ b , ∊ c and D, in addition to the most probable minimum residual. A 2D Laue fit with an inhomogeneous domain distribution provides a population map with ∊ b and ∊ c , reflecting strain components contributing to the film. The population map also leads to a reference residual as a guide for the strains contributing to the residual map. The advantages of the 2D Laue fits are discussed by comparison with the Scherrer, Williamson–Hall and Gaussian fitting methods for equivalent systems. The analyzed results indicate that the β-FeSi2 nanofilm was considerably small strained, which was also confirmed by transmission electron microscopy, implying a weak interface interaction between the film and the substrate.

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Exploring Mechanical Alloying to Produce Doped ZnO

Materials Physics and Chemistry ◽

10.18282/mpc.v1i3.581 ◽

2019 ◽

Vol 1 (3) ◽

pp. 1

Author(s):

Belén Sotillo ◽

María Esther Solana ◽

Paloma Fernández

Keyword(s):

Mechanical Alloying ◽

Lattice Parameter ◽

Grinding Process ◽

Particle Sizes ◽

X Ray Diffraction ◽

X Ray ◽

Doped Zno

In this work, a mixture of ZnO and CeO2 powders are subjected to a milling procedure to monitor the mechanical alloying processes. ZnO-CeO2 powders have been milled during 10 to 60 hours, and have been characterized by X-ray diffraction (XRD), UV-Vis absorption, Raman and photoluminescence spectroscopies, in order to study the present phases, the tensional state of material and particle sizes. The evolution of the phases presents with the time of milling, and the possible changes in the lattice parameter will help us to estimate the efficiency of the grinding process for obtaining Ce doped ZnO.

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Epitaxial Growth of Zinc-Blende Ain by Plasma Source Molecular Beam Epitaxy

MRS Proceedings ◽

10.1557/proc-570-297 ◽

1999 ◽

Vol 570 ◽

Cited By ~ 1

Author(s):

Margarita P. Thompson ◽

Gregory W. Auner ◽

Andrew R. Drews ◽

Tsvetanka S. Zheleva ◽

Kenneth A. Jones

Keyword(s):

Molecular Beam Epitaxy ◽

Electron Diffraction ◽

Molecular Beam ◽

Plasma Source ◽

High Energy ◽

Lattice Parameter ◽

High Energy Electron ◽

X Ray Diffraction ◽

X Ray ◽

Zinc Blende

ABSTRACTEpitaxial zinc-blende AIN films as thick as 2000Å were deposited on Si (100) substrates by plasma source molecular beam epitaxy (PSMBE). The metastable zinc-blende form of AIN was observed to occur when pulse d.c. power was supplied to the PSMBE hollow cathode source. Reflection High Energy Electron Diffraction (RHEED) showed that the films possess a four fold symmetry. X-Ray Diffraction (XRD) revealed two strong peaks corresponding to the (200) and (400) reflections from the zinc-blende AIN. The lattice parameter of the films was calculated to be approximately 4.373Å. TEM, performed on one of the films, revealed that the AIN is cubic, single crystalline and epitaxial with respect to the Si (100) substrate.

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Antiphase Boundaries in Ordered Ni3FE Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006221x ◽

1969 ◽

Vol 27 ◽

pp. 62-63

Author(s):

Y. H. Liu

Keyword(s):

Domain Size ◽

Antiphase Domain ◽

X Ray Diffraction ◽

X Ray ◽

Hardening Mechanism ◽

Superlattice Structure ◽

Disordered Phase ◽

Domain Boundaries ◽

Atomic Scattering ◽

The Difference

Ordered Ni3Fe crystals possess a LI2 type superlattice similar to the Cu3Au structure. The difference in slip behavior of the superlattice as compared with that of a disordered phase has been well established. Cottrell first postulated that the increase in resistance for slip in the superlattice structure is attributed to the presence of antiphase domain boundaries. Following Cottrell's domain hardening mechanism, numerous workers have proposed other refined models also involving the presence of domain boundaries. Using the anomalous X-ray diffraction technique, Davies and Stoloff have shown that the hardness of the Ni3Fe superlattice varies with the domain size. So far, no direct observation of antiphase domain boundaries in Ni3Fe has been reported. Because the atomic scattering factors of the elements in NijFe are so close, the superlattice reflections are not easily detected. Furthermore, the domain configurations in NioFe are thought to be independent of the crystallographic orientations.

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Interfacial properties of GaSb/InAs superlattices

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100149969 ◽

1993 ◽

Vol 51 ◽

pp. 826-827

Author(s):

M. E. Twigg ◽

B. R. Bennett ◽

J. R. Waterman ◽

J. L. Davis ◽

B. V. Shanabrook ◽

...

Keyword(s):

Gaas Substrate ◽

Molecular Beam ◽

Infrared Detector ◽

Interfacial Properties ◽

Ex Situ ◽

X Ray Diffraction ◽

Absorption Coefficients ◽

X Ray ◽

Short Period ◽

High Optical Absorption

Recently, the GaSb/InAs superlattice system has received renewed attention. The interest stems from a model demonstrating that short period Ga1-xInxSb/InAs superlattices will have both a band gap less than 100 meV and high optical absorption coefficients, principal requirements for infrared detector applications. Because this superlattice system contains two species of cations and anions, it is possible to prepare either InSb-like or GaAs-like interfaces. As such, the system presents a unique opportunity to examine interfacial properties.We used molecular beam epitaxy (MBE) to prepare an extensive set of GaSb/InAs superlattices grown on an GaSb buffer, which, in turn had been grown on a (100) GaAs substrate. Through appropriate shutter sequences, the interfaces were directed to assume either an InSb-like or GaAs-like character. These superlattices were then studied with a variety of ex-situ probes such as x-ray diffraction and Raman spectroscopy. These probes confirmed that, indeed, predominantly InSb-like and GaAs-like interfaces had been achieved.

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Local Strain Distribution in ZnO Microstructures Visualized with Scanning Nano X‐Ray Diffraction and Impact on Electrical Properties

Advanced Engineering Materials ◽

10.1002/adem.202100201 ◽

2021 ◽

pp. 2100201

Author(s):

Philipp Jordt ◽

Stjepan B. Hrkac ◽

Jorit Gröttrup ◽

Anton Davydok ◽

Christina Krywka ◽

...

Keyword(s):

Electrical Properties ◽

Strain Distribution ◽

Local Strain ◽

X Ray Diffraction ◽

X Ray

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Growth of sillenite Bi12FeO20 single crystals: structural, thermal, optical, photocatalytic features and first principle calculations

Scientific Reports ◽

10.1038/s41598-020-78598-3 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Durga Sankar Vavilapalli ◽

Ambrose A. Melvin ◽

F. Bellarmine ◽

Ramanjaneyulu Mannam ◽

Srihari Velaga ◽

...

Keyword(s):

Single Crystal ◽

Single Crystals ◽

Photoelectron Spectroscopy ◽

Diffraction Method ◽

Lattice Parameter ◽

First Principle ◽

X Ray Diffraction ◽

X Ray ◽

First Principle Calculations ◽

Photodegradation Efficiency

AbstractIdeal sillenite type Bi12FeO20 (BFO) micron sized single crystals have been successfully grown via inexpensive hydrothermal method. The refined single crystal X-ray diffraction data reveals cubic Bi12FeO20 structure with single crystal parameters. Occurrence of rare Fe4+ state is identified via X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). The lattice parameter (a) and corresponding molar volume (Vm) of Bi12FeO20 have been measured in the temperature range of 30–700 °C by the X-ray diffraction method. The thermal expansion coefficient (α) 3.93 × 10–5 K−1 was calculated from the measured values of the parameters. Electronic structure and density of states are investigated by first principle calculations. Photoelectrochemical measurements on single crystals with bandgap of 2 eV reveal significant photo response. The photoactivity of as grown crystals were further investigated by degrading organic effluents such as Methylene blue (MB) and Congo red (CR) under natural sunlight. BFO showed photodegradation efficiency about 74.23% and 32.10% for degrading MB and CR respectively. Interesting morphology and microstructure of pointed spearhead like BFO crystals provide a new insight in designing and synthesizing multifunctional single crystals.

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