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The average strain in local regions of synthetic diamond was determined using the energy Fourier-transform spectrum in the analysis of digital Kikuchi patterns. The degree of broadening of the diffraction bands and their intersections in the images caused by deformations is quantitatively described through the average spatial period and the area of the radial distribution of the energy spectrum. The planar distribution of local strains made it possible to determine their anisotropy in the crystal in magnitude and direction.

A discrete two-dimensional Fourier transform and the power Fourier spectrum are used for determination of average strains near cracks in a welded seam of Ni-Cr-Fe alloy. The alignment of Kikuchi images with the help of genetic algorithms and subtraction of white Gaussian noise made it possible to more fully take into account the influence of instrumental factors on the formation of electron backscatter diffraction patterns. Keywords: Ni—Cr—Fe alloy, welded seam, Kikuchi method, Fourier transform, deformation.

Opportunities of multi-beam X-ray diffraction are demonstrated for determination of lattice strains in heterostructures and multi-layered systems., This article presents the results of research on multi-layered heterostructures by a modified calculation technique of multiple X-ray diffraction. The AlxIn1−xSb heterostructure and a Zn(Mn)Se/GaAs(001) multi-layered system were used as models to specify conditions for cases of coincidental coplanar three-beam or coincidental noncoplanar four-beam X-ray diffraction. These conditions provide the means for a high-precision determination of lattice parameters and strain anisotropy in layers.

The authors put forward a procedure of determination of strain tensor components through the analysis of distribution of intensity of back-scattered electrons in Kikuchi patterns. The strain state has been studied in local areas of a synthetic diamond crystal produced by the temperature gradient method in the Fe–Al–C system through growing onto a diamond single crystal synthesized in the Ni–Mn–C system. Characteristic surfaces of the strain tensors and strain ellipsoids have been plotted; special features of strain distribution in the crystal have been analyzed. Diagonal tensor components have been determined from the changes of distributions of intensity of individual bands, the other components have been found from the displacements of axes of zones relative to their positions in the standard Kikuchi pattern.

A new approach has been proposed to determination of local strains in crystals using patterns of electrons backscattering diffraction (Kikuchi patterns) and discrete two-dimensional Fourier transformations. The new approach has been tested in studying diamond samples synthesized under different conditions. The results obtained have been found to agree well with the data obtained by other methods.

The histogram method has been proposed to determine strains in diamond crystals by the analysis of reflection electron diffraction bands in Kikuchi patterns. The anisotropy has been defined of the local strain distribution on the surface of two diamond samples produced by the temperature gradient method in the Fe-Al-C system and by growing on a surface of a statically synthesized diamond single crystal (Ni-Mn-C) in the Mg-C + Bor system.

High-precision determination of the absolute value of lattice parameter for cubic single crystals is demonstrated by the example of silicon using coincidental multi-beam X-ray diffraction realized by superposition of two three-beam reflections at fixed sample temperature. Based on a semikinematical approximation of X-ray scattering theory, the algorithm for calculation of multi-beam diffractograms is developed enabling a more thorough quantitative analysis of experimental results.

In this paper we demonstrate possibilities of electron backscattering diffraction technique (Kikuchi method) for determination of strain distribution in local areas of synthetic diamond samples. To increase the precision of lattice parameter determination a correlation method and corresponding software were used for accurate identification of coordinates of Kikuchi lines intersections on the Kikuchi patterns. Consequently, subjective factors influencing on accuracy at determination of displacements of image details were minimized. Samples have been investigated by scanning electron microscope "Zeiss" EVO-50 using CCD detector. The complex analysis of location changes of Kikuchi lines intersections and Kikuchi line intensity profiles permits to specify peculiarities of strain distribution for diamonds grown by various methods.

The precision of lattice parameter determination can be significantly risen providing superposition of closely set maxima at Renninger-scan, which are in addition structure and spectral sensitive. This superposition can be achieved by means of lattice parameters change or wavelenght variation. We have realized that in the cases of coincidental coplanar or noncoplanar multiple x-ray diffraction. We have studied evolution of an angular distance between diffraction maxima near the range of coincidental multiple x-ray diffraction depending on stochiometric composition and temperature of sample. It has been shown that sensitivity of multiple diffraction is Δφ/Δa≈13.3 sec of arc /10-6 Å in the region of coincidental coplanar or noncoplanar x-ray diffraction.© (2008) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

By a numerical solution of the system of Takagi differential equations, the influence of a thin subsurface strained layer and a system of equal strained layers on three-beam diffraction effects of X-ray scattering in A3B5 compounds and diamond crystals have been investigated. It is established that the degree of suppression or enhancement of three-beam anomalous transmission significantly depends on the influence of the parameters of the strained layer on various effects typical for each multiple configuration, as well as on the structural features of the crystals being considered.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Influence of 1D strains of different type on unusual x-ray transmission in Ge crystal is studied. The (111,1 11/200), (111,1 1 1/220) and (220,202/022) three-wave Laue diffractions of CuK(alpha )-radiation are considered at (mu) t>10. Research is carried out by numerical solution of Takagi equation system. It is shown that 1D distortions (equidistant banding, acoustic strain and layer hidden under surface) caused different transformations of two- and three- wave scattering areas. Each of considered strains has its own distinctive influence on multiple unusual transmission. It is explained by various character of interaction between diffracted waves that leads to redistribution of intensity in three-wave area. In some cases the considerable enhancement of three-wave unusual transmission is observed at slight strains.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.