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The effect of photon annealing on the occurrence of deformations in the crystal structure of boron−doped silicon wafers produced by the Czochralski (Cz−Si) was studied by the method of triple−X−ray diffraction. It was found that the traditional annealing of silicon wafers with polished surfaces on both sides by halogen lamps in Photonic Annealing (PA) and rapid thermal annealing modes (RTA) leads to compression deformation. The same process with the use of original photo− mask, which allows local processing produces multiple, spatially separated regions of the plate produced by Lосаl Photonic Annealing (LPA) at relatively low temperatures (less than 55 °C), gives rise to a tensile strain. This established effect is not observed if on the back side of the plates there is mechanical gettering layer. The mechanism explaining the experimental results can be used in the formation of the charge pump in the structure of the photo electric converters (PEC).

The diffraction properties of phase gratings with the period D = 1.6, 1.0 and 0.5 µm fabricated on an Si(111) crystal by e-beam lithography were studied by triple-axis X-ray diffraction. A 100 nm-thick tungsten layer was used as a phase-shift layer. It is shown that the presence of a grating as a phase-shift W layer on the surface of the Si(111) crystal causes the formation of a complicated two-dimensional diffraction pattern related to the diffraction of X-rays on the phase grating at the X-ray entrance and exit from the crystal. A model of X-ray diffraction on the W phase diffraction grating is proposed.

We have demonstrated for the first time the possibility of preparing high-purity and praseodymium- and dysprosium-doped solid solutions based on lead halides and alkali metals: Rb1 − xCsxPb2Cl5, Rb1 − xCsxPb2Br5, Rb1 − xKxPb2Cl5, and RbPb2Cl5 − yBry. According to X-ray diffraction data, Rb1 − xCsxPb2Cl5 and Rb1 − xCsxPb2Br5 crystals in the solid solution range are isostructural with the constituent double salts RbPb2Cl5 and RbPb2Br5, respectively. The double salt Rb0.5K0.5Pb2Cl5 is isostructural with KPb2Cl5, and the double mixed salt RbPb2Cl2.5Br2.5 is isostructural with RbPb2Br5. The Pr3+ and Dy3+ concentrations in crystals of the solid solutions and mixed salts were determined by inductively coupled plasma mass spectrometry (ICP-MS). In the Rb1 − x (Cs, K)xPb2Hal5 (Hal = Cl, Br) solid solutions, the dopants were observed to be nonuniformly distributed over the host. According to ICP-MS analysis data and absorption spectra, the Pr3+ and Dy3+ concentrations in the RbPbCl2.5Br2.5 crystals were higher than those in RbPb2Br5.

In this work, a set of local electron irradiations has been used to fabricate domain gratings in conventional lithium tantalate crystals. The Z and Y-cuts of the crystals were irradiated in the SEM at 25 kV, using different distributions of square point writing by an e-beam. Peculiarities of the domain-inverted gratings that were located near the surface of the Y- cuts and in the crystal bulk of the Z-cuts have been investigated at the different drawing motives, doses of irradiations and crystallographic directions of e-beam movement during writing. The domain structures were examined in optical microscopes after chemical etching of the irradiated samples. The crystallographic Y directions were found to be important in e-beam drawing on Z-cut surfaces. Account should be taken of the crystallographic Z direction during e-beam writing and long domain-inverted grating fabrication on the Y-cuts. For both polar cuts, the reduction of intervals between the sequences of local irradiated areas down to 2–3 μm was ...

The process of diffuse x-ray scattering from a crystal modulated by surface acousdtic wave is considered. It is shown that the angular distribution of the diffuse scattering intensity depends on variation of the gradient of the ultrasonic wave amplitude in depth of the crystal. This distribution is formed both in the vicinity of the main diffraction peak and around its satellites. Theoretical reciprocal space maps of the diffuse scattering intensity distribution are obtained and compared to the experimental data.

Independent piezoelectric strain coefficients d11 and d14 in disordered La3Ga5.3Ta0.5Al0.2O14 (LGTA) and ordered Ca3TaGa3Si2O14 (CTGS) crystals of the langasite family were measured by high-resolution X-ray diffraction (HRXRD) under external electric field application which causes changes in the interplanar spacing because of the reverse piezoelectric effect. The experiment showed that the piezoelectric strain coefficients can be precisely determined by measuring changes in the interplanar spacing using the optical scheme of a triple-axis X-ray diffractometer. The measured independent piezoelectric strain coefficients d11 and d14 for LGTA and CTGS crystals were d11(LGTA)=6.455·10-12 C/N, d14(LGTA)=-5.117·10-12 C/N; d11(CTGS)=3.330·10-12 C/N, d14(CTGS)=-15.835·10-12 C/N.

X-ray diffraction on the La3Ga5SiO14 (LGS) crystal modulated by surface (SAW) and pseudo-surface acoustic waves (PSAW) with wavelength of Λ=6 μm was studied using a double axis X-ray diffractometer at the BESSY II synchrotron radiation source. The propagation of SAW and PSAW leads to sinusoidal modulation of the crystal lattice and gives rise to diffraction satellites on the rocking curve, with the intensity and angular divergence between the diffraction satellites depending on the wavelength and amplitude of the crystal lattice acoustic modulation. The analysis of diffraction spectra enables the determination of the amplitude and acoustic wavelengths, and power flow angles of acoustic energy propagation. The investigation of acoustic wave fields showed that PSAW is a flowing back wave.

A five-component crystal of lanthanum-gallium silicate group La3Ga5.3Ta0.5Al0.2O14 (LGTA) was grown by the Czochralski method. The LGTA crystal possesses unique thermal properties and substitution of Al for Ga in the unit cell leads to a substantial increase of electrical resistance at high temperatures. The unit cell parameters of LGTA were determined by powder diffraction. X-ray topography was used to study the crystal structure perfection: the growth banding normal to the growth axis were visualized. Excitation and propagation of surface acoustic waves (SAW) were studied by the double crystal X-ray diffraction at the BESSY II synchrotron radiation source. The analysis of the diffraction spectra of acoustically modulated crystals permitted the determination of the velocity of acoustic wave propagation and the power flow angles in different acoustic cuts of the LGTA crystal.

Using x-ray diffraction technique temperature dependence of SAW excitation frequency was measured for temperature range from 20 to 400 °C. Crystal lattice deformation caused by SAW propagation was calculated.

A five-component crystal of lanthanum-gallium silicate family Ca3TaGa3Si2O14 (CTGS) was grown by the Czochralski method. The CTGS crystal, like langasite crystals La3Ga5SiO14, possesses unique temperature properties and the fewer number of the Ga atoms in the unit cell makes the density much lower and, consequently, increases the velocity of acoustic wave propagation. The unit cell parameters were determined by the powder diffraction technique. The defects in the CTGS crystal structure were studied by X-ray topography which enables the visualization of growth banding characteristics of crystal grown by Czochralski method. Surface acoustic wave (SAW) propagation in the CTGS crystal was investigated by the high-resolution X-ray diffraction method. The velocities of propagation and power flow angles of SAW in the Yand X-cuts of the CTGS crystal were determined from the X-ray diffraction spectra.

A ferroelectric domain structure formed in the X cut of a LiNbO3 crystal by aftergrowth thermoelectrical treatment was studied by x-ray diffraction and topography methods. An external electric field applied along the X axis to the crystal causes shift deformations due to the reverse piezoelectric effect, which permits visualization of domain structures in the X cut of a LiNbO3 crystal. Oppositely directed inclinations of reflecting planes in adjacent domains, caused by the reverse piezoelectric effect, give rise to different diffraction angles in neighboring domains and make visualization of domain structure possible.

Regular domain structures formed in ferroelectric LiNbO3 and LiTaO3 crystals by the aftergrowth thermoelectrical treatment technique were studied by high-resolution x-ray diffraction and topography under an external electric field applied to the crystals. The application of an external electric field to the crystal causes longitudinal and shift deformations due to the reverse piezoelectric effect and, as a result, inverse changes in the Bragg angle values in adjacent domains. The changes in the Bragg angle values lead to an increase in the x-ray topographic contrast of the domain structure images and allow the direction of the polar and piezoelectrically active axis in adjacent domains to be unambiguously determined. In addition, it was shown that the x-ray diffraction technique can be used to study the behavior of elastic deformations near domain boundaries under an external electric field applied to crystals.

X-ray Bragg diffraction on the X, Y, and (011) cuts of a langasite crystal (La/sub 3/Ga/sub 5/SiO/sub 14/, LGS) modulated by a Rayleigh surface acoustic wave (SAW) has been studied using a high-resolution X-ray topography method. This X-ray topography technique was used for direct imaging of the standing SAW in LGS, to measure the SAW amplitudes and power flow angles, to visualize the diffraction patterns in acoustic beams, and to study the process of the SAW interaction with crystal structure defects.