High resolution X-ray diffraction mapping studies on the domain structure of LaAlO3 single crystal substrates and its influence on SrTiO3 film growth

ABSTRACTFor nitride based devices such as LEDs, high power FETs and laser diodes, single crystal substrates of AlN are highly desirable. While the sublimation technique is suitable for growing bulk AlN crystals, appropriate seeds are also necessary for growing large diameter oriented boules. 4H- and 6H-SiC substrates which are readily available commercially can potentially be implemented as seeds for bulk AlN growth. However, issues regarding SiC decomposition at high temperatures, thermal expansion mismatch, single crystal growth, etc. need to be addressed. Towards this end, a series of growth experiments have been carried out in a resistively heated reactor using on and off-axis 4H- and 6H-SiC substrates as seeds for AlN growth from the vapor phase. Several hundred microns thick AlN layers have been grown under different growth conditions. Synchrotron white beam x-ray topography (SWBXT) has been used to map the defect distribution in the grown layers and high resolution triple axis x-ray diffraction (HRTXD) experiments were carried out to record reciprocal space maps from which tilt, mismatch and strain data can be obtained. These results are analyzed with respect to the growth conditions in order to gain a better understanding of this growth process.

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Scatterless hybrid metal–single-crystal slit for small-angle X-ray scattering and high-resolution X-ray diffraction

Journal of Applied Crystallography ◽

10.1107/s0021889808031129 ◽

2008 ◽

Vol 41 (6) ◽

pp. 1134-1139 ◽

Cited By ~ 98

Author(s):

Youli Li ◽

Roy Beck ◽

Tuo Huang ◽

Myung Chul Choi ◽

Morito Divinagracia

Keyword(s):

High Resolution ◽

Single Crystal ◽

Small Angle ◽

Incident Beam ◽

Single Crystal Substrate ◽

X Ray Diffraction ◽

Metal Base ◽

X Ray ◽

X Ray Scattering ◽

Ray Scattering

A simple hybrid design has been developed to produce practically scatterless aperture slits for small-angle X-ray scattering and high-resolution X-ray diffraction. The hybrid slit consists of a rectangular single-crystal substrate (e.g.Si or Ge) bonded to a high-density metal base with a large taper angle (> 10°). The beam-defining single-crystal tip is oriented far from any Bragg peak position with respect to the incident beam and hence produces none of the slit scattering commonly associated with conventional metal slits. It has been demonstrated that the incorporation of the scatterless slits leads to a much simplified design in small-angle X-ray scattering instruments employing only one or two apertures, with dramatically increased intensity (a threefold increase observed in the test setup) and improved low-angle resolution.

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Irradiated cubic single crystal SiC as a high temperature sensor

MRS Proceedings ◽

10.1557/proc-792-r5.3 ◽

2003 ◽

Vol 792 ◽

Cited By ~ 3

Author(s):

Alex A. Volinsky ◽

Lev Ginzbursky

Keyword(s):

Single Crystal ◽

Film Growth ◽

Space Shuttle ◽

Turbine Blades ◽

Maximum Temperature ◽

X Ray Diffraction ◽

Ceramic Tiles ◽

X Ray ◽

Single Crystal Sic ◽

Technology Modeling

ABSTRACTRadiation is known to cause point defects formation in different materials. In the case of cubic SiC single crystal radiation flux on the order of 2·1020 neutrons/cm2 at 0.18 MeV causes over 3% volume lattice expansion. Radiation-induced strain (measurable by X-Ray diffraction) can be relieved when the annealing temperature exceeds the temperature of irradiation. Based on this effect the original technology of maximum temperature measurement was developed a while ago. Single crystal SiC sensor small size (200–500 microns), wide temperature range (150–1450 °C), “no-lead” installation, and exceptional accuracy make it very attractive for use in small, rotating and “hard-to-access” parts, including, but not limited to gas turbine blades, space shuttle ceramic tiles, automobile engines, etc. With the advances in X-Ray diffraction measurements, crystal and thin film growth techniques, it is the time to revise and update this technology. Modeling radiation damage, as well as annealing effects are also beneficial.

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Absolute configuration and domain structure of AlPO4-5 studied by single crystal X-ray diffraction

Microporous and Mesoporous Materials ◽

10.1016/s1387-1811(00)00161-x ◽

2000 ◽

Vol 38 (2-3) ◽

pp. 403-412 ◽

Cited By ~ 30

Author(s):

G.J Klap ◽

H van Koningsveld ◽

H Graafsma ◽

A.M.M Schreurs

Keyword(s):

Single Crystal ◽

Domain Structure ◽

Absolute Configuration ◽

X Ray Diffraction ◽

X Ray

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Domain separation in single-crystal (ND4)2Cu(SO4)2⋅6D2O studied by x-ray diffraction at high resolution

Physical Review B ◽

10.1103/physrevb.48.13372 ◽

1993 ◽

Vol 48 (18) ◽

pp. 13372-13377 ◽

Cited By ~ 2

Author(s):

Brian N. Figgis ◽

Philip A. Reynolds ◽

Jonathan C. Hanson ◽

Ilpo Mutikainen

Keyword(s):

High Resolution ◽

Single Crystal ◽

X Ray Diffraction ◽

X Ray ◽

Domain Separation

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Synthesis, high-resolution NMR spectroscopic analysis, and single-crystal X-ray diffraction of isoxazoline tetracycles

Carbohydrate Research ◽

10.1016/s0008-6215(02)00258-6 ◽

2002 ◽

Vol 337 (24) ◽

pp. 2419-2425 ◽

Cited By ~ 3

Author(s):

Mirta L Fascio ◽

Angel Alvarez-Larena ◽

Norma B D'Accorso

Keyword(s):

High Resolution ◽

Single Crystal ◽

Spectroscopic Analysis ◽

X Ray Diffraction ◽

X Ray ◽

High Resolution Nmr

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Structure of fluorite-like compound based on Nd5Mo3O16with lead partly substituting for neodymium

Acta Crystallographica Section B Structural Science Crystal Engineering and Materials ◽

10.1107/s2052520615003315 ◽

2015 ◽

Vol 71 (2) ◽

pp. 186-193 ◽

Cited By ~ 7

Author(s):

Alexander M. Antipin ◽

Natalia I. Sorokina ◽

Olga A. Alekseeva ◽

Alexandra N. Kuskova ◽

Elena P. Kharitonova ◽

...

Keyword(s):

Crystal Structure ◽

High Resolution ◽

Single Crystal ◽

Experimental Verification ◽

X Ray Diffraction ◽

Transmission Microscopy ◽

X Ray ◽

Oxygen Ion ◽

First Time ◽

Edx Microanalysis

A single crystal of Nd5Mo3O16with lead partly substituting for neodymium, which has a fluorite-like structure, was studied by precision X-ray diffraction, high-resolution transmission microscopy and EDX microanalysis. The crystal structure is determined in the space group Pn\bar 3n. It was found that the Pb atoms substitute in part for Nd atoms in the structure and are located in the vicinity of Nd2 positions. Partial substitutions of Mo cations for Nd positions and of Nd for Mo positions in crystals of theLn5Mo3O16oxide family are corroborated by X-ray diffraction for the first time. The first experimental verification of the location of an additional oxygen ion in the voids abutting MoO4tetrahedra was obtained.

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