Absolute measurement of lattice parameter in single crystals and epitaxic layers on a double-crystal X-ray diffractometer

AbstractThe high intensity and large beam size of a synchrotron radiation source have been exploited in order to obtain double crystal X-ray topographs of whole 2in. and 3in. slices of semi-insulating LEC GaAs single crystals. Exposure times, typically 30 minutes for high resolution topographs, are at least one order of magnitude down on those required when using a conventional source. Variations in relative lattice parameter and lattice tilt have been measured as a function of position on the slice. The defect structure has been imaged and dislocations are seen in cellular configurations, slip bands and linear arrays (lineage), the latter of which are shown to be associated with small lattice tilts, typically 30”. The defect structure revealed on the topographs has been correlated with 1μm infrared absorption micrographs which are believed to represent the concentration of the dominant deep level EL2.

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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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Generation of Defects and Strain by Ion Implantation in Ge (100) Single Crystals, and in Pseudomorphic GexSi1-x Films Grown on Si (100)

MRS Proceedings ◽

10.1557/proc-262-1079 ◽

1992 ◽

Vol 262 ◽

Cited By ~ 7

Author(s):

D. Y. C. Lie ◽

A. Vantomme ◽

F. Eisen ◽

M. -A. Nicolet ◽

V. Arbet-Engels ◽

...

Keyword(s):

Ion Implantation ◽

Single Crystals ◽

Room Temperature ◽

Defect Concentration ◽

Double Crystal ◽

X Ray ◽

Positive Strain ◽

Independent Coefficient ◽

The Relationship ◽

Si Ion Implantation

ABSTRACTWe have studied the damage and strain produced in Ge (100) single crystals by implantation of various doses of 300 keV 28Si ions at room temperature. The analyzing tools were x-ray double-crystal diffractometry, and MeV 4He channeling spectrometry. The damage induced by implantation produces positive strain in Ge (100). The maximum perpendicular strain and maximum defect concentration rise nonlinearly with increasing dose. These quantities are linearly related with a dose-independent coefficient of ∼ 0.013 for Ge (100) single crystals implanted at room temperature. The results are compared with those available for Si (100) self-implantation. We have also monitored the strain and defects generated in pseudomorphic Ge0.1Si0.9/Si (100) films induced by room temperature 28Si ion implantation. It is found that the relationship between the strain and defect concentration induced by ion implantation is no longer a simple linear one.

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Graded X-ray Optics for Synchrotron Radiation Applications

Journal of Synchrotron Radiation ◽

10.1107/s0909049597019043 ◽

1998 ◽

Vol 5 (3) ◽

pp. 239-245 ◽

Cited By ~ 9

Author(s):

A. Erko ◽

M. Veldkamp ◽

W. Gudat ◽

N. V. Abrosimov ◽

S. N. Rossolenko ◽

...

Keyword(s):

Synchrotron Radiation ◽

Magnetron Sputtering ◽

Single Crystals ◽

Theoretical Data ◽

Lattice Parameter ◽

Structure And Properties ◽

Czochralski Technique ◽

Spectral Measurements ◽

Optical Elements ◽

X Ray

Using X-ray diffractometry and spectral measurements, the structure and properties of graded X-ray optical elements have been examined. Experimental and theoretical data on X-ray supermirrors, which were prepared by the magnetron sputtering technique using precise thickness control, are reported. Measurements on graded aperiodic Si1−x Ge x single crystals, which were grown by the Czochralski technique, are also presented. The lattice parameter of such a crystal changes almost linearly with increasing Ge concentration. The measurements indicate that Si1−x Ge x crystals with concentrations up to 7 at.% Ge can be grown with a quality comparable to that of pure Si crystals.

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On the dilatation of synthetic type Ib diamond by substitutional nitrogen impurity

Philosophical Transactions of the Royal Society of London Series A Physical and Engineering Sciences ◽

10.1098/rsta.1991.0135 ◽

1991 ◽

Vol 337 (1648) ◽

pp. 497-520 ◽

Cited By ~ 46

Keyword(s):

Infrared Absorption ◽

Infrared Absorption Spectrum ◽

Internal Standard ◽

Optical Microscope ◽

Lattice Parameter ◽

Bragg Angle ◽

Growth Sector ◽

Double Crystal ◽

X Ray ◽

Nitrogen Impurity

Sequences of high Bragg-angle (0 B = 74°) double-crystal X-ray topographs taken at the SRS (Daresbury, U.K.) have yielded precise measurements of lattice parameter differences between growth sectors of different crystallographic forms in a large undoped synthetic diamond whose type Ib infrared absorption spectrum (principal peak at 1130 cm -1 ) indicated atomically dispersed nitrogen, singly substituting for carbon, as the only detectable impurity. The plate-shaped specimen, polished parallel to (110), 5.0 x 3.2 mm 2 in area, 0.7 mm thick, possessed an unusually well developed (110) growth sector containing nitrogen impurity concentration of only ca. 10 -6 , which served as an internal standard of pure-diamond lattice parameter with which lattice parameters of nitrogen-containing growth sectors were compared. The specimen’s suitability for precision diffractometry was checked by comprehensive tests using optical microscope techniques, cathodoluminescence and single-crystal X-ray topography. The double-crystal combination was silicon reference crystal, asymmetric 175 reflection, with diamond specimen symmetrical 440 reflection. The principal measurement was the increase of the lattice parameter, a 0 , of the (111) growth sector (nitrogen content 88 + 7 parts per 10 6 atomic) relative to that of the (110) sector: Aa 0 / a 0 = 1.18 + 0.07 x 10 -5 . In terms of measured infrared absorption coefficient at 1130 cm -1 , this gives Aa 0/a 0 = (2.95 + 0.27) x 10 -6 [p(1130 cm -1 )/cm -1 ], which is believed to hold for growth sectors of all crystallographic forms. Combination with the nitrogen assay findings of Woods, van Wyk & Collins ( Phil. Mag. B 62. 589-595 (1990)) provides a direct relation to c N , the fractional atomic concentration of substitutional nitrogen, as A a 0 / a 0 = (0.14 + 0.02) c N , which indicates that the effective volume of a single substitutional nitrogen atom in diamond is 1.41 +0.06 times that of the carbon atom it replaces. This substantial dilatation conflicts with several models for the substitutional nitrogen structure.

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A high-resolution double-crystal diffractometer method for the measurement of lattice parameter in single crystals

Journal of Crystal Growth ◽

10.1016/0022-0248(89)90528-9 ◽

1989 ◽

Vol 96 (2) ◽

pp. 316-326 ◽

Cited By ~ 12

Author(s):

M. Fatemi

Keyword(s):

High Resolution ◽

Single Crystals ◽

Lattice Parameter ◽

Double Crystal ◽

Double Crystal Diffractometer

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AN X-RAY DOUBLE-CRYSTAL SPECTROMETRIC INVESTIGATION OF THE BEHAVIOUR OF α-LiIO3 SINGLE CRYSTALS UNDER THE ACTION OF ELECTROSTATIC FIELD

Acta Physica Sinica ◽

10.7498/aps.27.126 ◽

1978 ◽

Vol 27 (2) ◽

pp. 126

Author(s):

LIANG JING-KUI ◽

YI SU-SHENG

Keyword(s):

Single Crystals ◽

Electrostatic Field ◽

Spectrometric Investigation ◽

Double Crystal ◽

X Ray

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X-Ray Double Crystal Diffractometer Investigations of Implanted Silicon: D+And N+

Advances in X-ray Analysis ◽

10.1154/s0376030800011174 ◽

1971 ◽

Vol 15 ◽

pp. 504-515 ◽

Cited By ~ 5

Author(s):

E. H. teKaat ◽

G. H. Schwuttke

Keyword(s):

Radiation Damage ◽

Lattice Parameter ◽

Double Peak ◽

Double Crystal ◽

X Ray ◽

Projected Range ◽

Insight Into ◽

Double Crystal Diffractometer

Double crystal diffractometer measurements on silicon bombarded to a fluence >1016ions/cm2with 1 MeV deuterium and 2 MeV nitrogen are reported. Such measurements provide insight into radiation damage in silicon through the observation of Bragg case pendelloesung fringes and double peak rocking curves. Bragg case pendelloesung fringes are used to determine nondestructively the projected range of ions in silicon. Double peak rocking curves are used to measure changes in lattice parameter with the ion dose. Finally, a model of radiation damage in silicon is presented.

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Determination of Zinc Sulfide and Cadmium Sulfide in Solid Solutions of Small Single Crystals Used for Semiconductors by X-Ray and Chemical Methods

Advances in X-ray Analysis ◽

10.1154/s0376030800001518 ◽

1961 ◽

Vol 5 ◽

pp. 142-152

Author(s):

Frank L. Chan

Keyword(s):

Cadmium Sulfide ◽

Single Crystals ◽

Zinc Sulfide ◽

Solid Solutions ◽

Lattice Parameter ◽

Chemical Methods ◽

Pure Zinc ◽

X Ray ◽

Mixed Sulfides

AbstractSingle crystals of cadmium sulfide and zinc sulfide have been grown and studied intensively by the Solid State Physics group at the Aeronautical Research Laboratory. The physical phenomena such as reflection, transmission, ultraviolet-excited emission, and electrical resistivity have been observed and characterized on single crystals of these sulfides. Much interest concerning these phenomena has also been centered on single crystals containing both cadmium sulfide and zinc sulfide.For research purposes, mixed crystals as small as a few tenths of 1 mg or less, to 0.5 g of the mixed sulfides, are being prepared. Special chemical methods are required to determine these constituents in them quantitatively. At times, these chemical methods are not applicable, since these methods invariably consume the sample, and, as a result, other observations on the same crystals cannot be performed.Changes in lattice parameter in single crystals of mixed sulfides as compared to pure zinc sulfide or cadmium sulfide provide excellent means for the determination of the percentage of these sulfides. In the X-ray method, single crystals used for the determination of the lattice parameters remain intact. The equipment adopted, procedure used, and the data obtained are illustrated and discussed.In the present study, crystals of cadmium sulfide (greenockite), alpha-zinc sulfide (wurtzite) and solid solutions of these two sulfides having a hexagonal unit cell were used. Since the lattice parameter a0 is found to follow Vegard's law, single-crystal rotation photographs described in this paper were obtained by rotating crystals around the c axis; the lattice parameter was determined with high precision by scanning along the zero-layer line with a microphotometer.

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