Performance of a double crystal diffractometer with different channel-cut perfect Si crystals

2000 ◽  
Vol 276-278 ◽  
pp. 124-125 ◽  
Author(s):  
D Bellmann ◽  
P Staron ◽  
P Becker
Keyword(s):  
Double Crystal ◽  
Double Crystal Diffractometer

The Use of a Multi-Double-Crystal Diffractometer to Investigate Nickel Domains

1997 ◽  
Vol 30 (5) ◽  
pp. 849-853 ◽  
Author(s):  
W. Treimer ◽  
A. Höfer ◽  
H. Strothmann
Keyword(s):  
Single Crystals ◽  
Domain Structure ◽  
Small Angle ◽  
Angular Resolution ◽  
Main Peak ◽  
High Angular Resolution ◽  
Bloch Wall ◽  
Double Crystal ◽  
First Results ◽  
Double Crystal Diffractometer

The investigations of the domain structure in Ni single crystals is best performed with a double-crystal diffractometer. Conventional small-angle instruments do not have the necessary angular resolution to distinguish satellites of a main peak due to spin-dependent refraction of unpolarized neutrons by Bloch walls in Ni. With the help of a double-crystal diffractometer operating with lamellae crystals as monochromator and analyzer, the angular resolution is maintained but the intensity enhanced by a factor of 5.4. Within a series of measurements, it was possible to investigate Ni domains due to the high angular resolution of the new multi-double-crystal instrument and this improved intensity. The first results of the domain structure in (110) Ni single crystals and a good estimation of the Bloch wall thickness are given.

Defect structure analysis of polycrystalline materials by computer-controlled double-crystal diffractometer with position-sensitive detector

1983 ◽  
Vol 16 (1) ◽  
pp. 89-95 ◽  
Author(s):  
R. Yazici ◽  
W. Mayo ◽  
T. Takemoto ◽  
S. Weissmann
Keyword(s):  
Position Sensitive Detector ◽  
Polycrystalline Materials ◽  
Sensitive Detector ◽  
Double Crystal ◽  
Rocking Curve ◽  
X Ray ◽  
Local Lattice ◽  
Position Sensitive ◽  
The Individual ◽  
Double Crystal Diffractometer

The method represents an extension of a previously developed X-ray double-crystal diffractometer method when a film was used to record the crystallite reflections, each reflecting crystallite being regarded as the second crystal of a double-crystal diffractometer. By utilizing a position-sensitive detector (PSD) with interactive computer controls, the tedious and limiting task of data acquisition and analysis is greatly simplified. The specimen is irradiated with crystal-monochromated radiation and the numerous microscopic spots emanating from the reflecting crystallites are recorded separately by the position-sensitive detector and its associated multichannel analyzer at each increment of specimen rotation. An on-line minicomputer simultaneously collects these data and applies the necessary corrections. This process is then automatically repeated through the full rocking-curve range. The computer carries out the rocking-curve analysis of the individual crystallite reflections as well as that of the entire reflecting crystallite population. The instrument is provided with a specimen translation device which permits analysis of large sections of solid specimens. Thus, sites of local lattice defects induced either mechanically, chemically or by radiation can rapidly be established and quantitatively determined in terms of rocking-curve parameters as well as imaged by X-ray topography, by inserting a film in front of the PSD. The versatility and usefulness of the method is demonstrated by examples given from studies of fracture, fatigue and stress-corrosion cracking of commercial alloys.

Digital X-Ray Rocking Curve Topography

1986 ◽  
Vol 82 ◽  
Author(s):  
T. S. Ananthanarayanan ◽  
R. G. Rosemeier ◽  
W. E. Mayo ◽  
J. H. Dinan
Keyword(s):  
Bragg Reflection ◽  
Strain Tensor ◽  
Epitaxial Films ◽  
Double Crystal ◽  
Rocking Curve ◽  
X Ray ◽  
Density Maps ◽  
First Time ◽  
Considerable Body ◽  
Double Crystal Diffractometer

SUMMARYThere is a considerable body of work available illustrating the significance of X-ray rocking curve measurements in micro-electronic applications. For the first time a high resolution (100-150µm) 2-dimensional technique called DARC (Digital Autcmated Rocking Curve) topography has been implemented. This method is an enhancement of the conventional double crystal diffractometer using a real time 2-dimensional X-ray detector.Several materials have been successfully examined using DARC topography. Same of these include: Si, GaAs, AlGaAs, InGaAs, HgMnTe, Al, Inconel, steels, etc. By choosing the appropriate Bragg reflection multi-layered micro-electronic structures have been analyzed nondestructively. Several epitaxial films, including HgCdTe and ZnCdTe, grown by molecular beam epitaxy, have also been characterized using iARC topography. The rocking curve half width maps can be translated to dislocation density maps with relative ease. This technique also allows the deconvolution of the micro-plastic lattice strain ccaponent from the total strain tensor.

Surface Morphology and Lattice Misfit in Yig and La: Yig Films Grown by Lpe Method on GGG Substrate

1997 ◽  
Vol 494 ◽  
Author(s):  
Duk-yong Choi ◽  
Su-jin Chung
Keyword(s):  
Lattice Misfit ◽  
Growth Conditions ◽  
Lattice Parameter ◽  
Double Crystal ◽  
Lattice Matching ◽  
Flux System ◽  
La Doped ◽  
Effective Distribution Coefficient ◽  
Double Crystal Diffractometer ◽  
Effective Distribution

ABSTRACTY3Fe5O12(YIG) and La-doped YIG films were grown on the {111} GGG substrate using the PbO-B2O3 flux system. Pb, La incorporation and lattice misfit and annealing behaviors were studied. In the case of LPE growth of YIG film, lead ions from flux are substituted inevitably, and they play an important role in controlling film misfit. For a complete lattice matching, high supercooling is necessary in pure YIG growth, but this induces high defect concentration. In this experiment, La ions were added in the solution to sufficiently increase lattice parameter of the film grown under low supercooling. The concentration of substituted Pb and La were increased as the growth temperature was lowered and growth rate increased. The effective distribution coefficient of La was about 0.2 at a supercooling of 30 °C. The optimum growth conditions which bring about very small misfit were determined by measuring the misfit by double crystal diffractometer. Strain distributions of pre-annealed and annealed samples were investigated by triple crystal diffractometer.

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