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Ferroelectric LiNb1–x Ta x O3 solid solutions with various Nb/Ta ratio were grown from the melt by the Czochralski method. The exact composition of the grown crystals was determined by inductively coupled plasma atomic mass spectrometry. The dependence of the crystal composition on the composition of the initial melt was obtained and explained by a wide separation between the phase boundaries of the liquid and solid phases on the LiNbO3–LiTaO3 phase diagram. Using high-resolution X-ray diffraction, the parameters a and c of a crystal unit cell were determined (LiNb0.88Ta0.12O3: a = 5.1574 Å and c = 13.8498 Å). Further, the Curie temperature T C of the crystals was measured using the differential scanning calorimetry technique. T C was found to depend on the composition of the crystals that allowed conditions for the monodomainization of the grown crystals to be defined (LiNb0.88Ta0.12O3: T C = 1102°C; LiNb0.33Ta0.67O3: T C = 794°C). Finally, the velocity of surface acoustic waves was determined by scanning electron microscopy and X-ray diffraction techniques (YZ-cut of a LiNb0.88Ta0.12O3 crystal: V = 3440 m s−1).

The influence of bulk acoustic wave excitation in langasite crystal on Raman spectra was studied. It was found that acoustic wave propagating in the crystal volume changes the intensity and position of the Raman scattering lines. Under bulk acoustic wave propagation conditions, Raman peak intensity changes less on 5% and peak position shifts on 0.5 cm−1. To detect such small changes, principal component analysis of Raman spectra was used.

The effect of photon annealing on deformation in the crystal structure of boron doped Cz-Si wafers has been studied using triple crystal X-ray diffraction. Conventional annealing of the entire surface of double-side polished silicon wafers with halogen lamps (photon annealing mode) and rapid thermal annealing produce compression deformation. Annealing with special phototemplate providing for local annealing of multiple separated wafer areas (local photon annealing mode) at relatively low wafer temperatures (less than 55 °C) produces tensile deformation. This effect however is not observed if the reverse side of the annealed wafer contains a mechanical gettering layer. A mechanism explaining the experimental results has been suggested and can be used for the synthesis of charge pumps in photoelectric converter structures.

The possibilities are presented of X-ray diffraction methods for studying the propagation of surface acoustic waves (SAWs) in solids, including diffraction under total external reflection conditions and Bragg diffraction, using acoustically modulated X-ray multilayer mirrors and crystals. SAW propagation was studied using both meridional and sagittal diffraction geometries where the SAW wavevectors and X-ray photons are collinear or perpendicular, respectively. SAW propagation in a crystal leads to sinusoidal modulation of the crystal lattice and the appearance of diffraction satellites on the rocking curve. The intensities and angular positions of these diffraction satellites are determined by the SAW wavelength, amplitude and attenuation. Therefore, diffraction methods allow the analysis of the SAW propagation process and determination of SAW parameters. The influence of X-ray energy on diffraction by acoustically modulated crystals is studied for the first time. It is shown that changes in the X-ray energy can change the angular region where diffraction satellites exist under conditions of total external reflection. By contrast, in the Bragg diffraction region changes in the X-ray photon energy lead to changes in the X-ray penetration depth into the crystal and redistribution of the diffracted intensity among diffraction satellites, but do not change the angular divergence between diffraction satellites on the rocking curve. It is also shown that, in X-ray diffraction on acoustically modulated crystals on a number of successive reflections, a decrease in interplanar spacing leads to an increase in the number of diffraction satellites and a redistribution of diffracted radiation between them.

Ferroelectric LiNb

Results of measurements of independent piezoelectric moduli d 11 and d 14 in Ca3NbGa3Si2O14, La3Ga5.5Ta0.5O14 and La3Ga5SiO14, promising single crystals of the calcium gallogermanate structural type, are presented. The moduli were measured with a triple-axis X-ray diffractometer under an external electric field which causes changes in the interplanar distances due to the reverse piezoelectric effect. The results of the X-ray diffractometry measurements agree fairly well (within less than 10%) with the results obtained by different methods.

The results of studying a two-dimensional X-ray focusing by an off-axis grazing incidence phase Fresnel zone plate on the laboratory X-ray source are presented. This optics enables obtaining a focal spot of ~2 µm on the laboratory X-ray source with a focusing efficiency of ~30% at a high signal/noise ratio.

We report direct optical reading of resistive switching in an amorphous TiO2 film. Changing TiO2 film conductivity under an applied electric field causes a change in the film reflection coefficient. To find this phenomenon, a sample with Al electrodes deposited on an amorphous TiO2 film in the form of an interdigital transducer was used. The experimental characteristic of a device shows a hysteresis of the reflection coefficient repeating the change in resistance under an applied electric field.

Development and search for new advanced materials of the lanthanum gallium silicate group with unique thermal properties is of great importance for the development of acoustoelectronics based on volume and surface acoustic waves. The processes of surface acoustic wave excitation and propagation in the La3Ga5.3Ta0.5Al0.2O14 crystal was studied using a double-crystal X-ray diffractometer with a BESSY II synchrotron radiation source. The X-ray diffraction spectra of acoustically modulated crystals were used to measure the surface acoustic wave velocity and power flow angles in different acoustic cuts of the La3Ga5.3Ta0.5Al0.2O14 crystal.

We report the epitaxial growth of c-plane GaN films on a novel langasite (La3Ga5SiO14, LGS) substrate by plasma-assisted molecular beam epitaxy. The in-plane epitaxial relationship and the structural properties of GaN films on an LGS substrate were investigated using in situ reflective high energy electron diffraction (RHEED), high resolution X-ray diffraction (HR-XRD) and Raman spectroscopy. The in-plane epitaxial relationship between GaN and LGS determined using RHEED pattern was found to be GaN[100]//LGS[210] and GaN[110]//LGS[140]. HR-XRD results confirmed the exact epitaxial relationship, and showed that six reflection peaks of GaN(102) were shifted around 19° from those of LGS(102). Raman analysis revealed that a minute compressive strain still existed in the GaN film due to the very small lattice mismatch between GaN and LGS. The results obtained in this study demonstrate that the nearly lattice-matched LGS can be a promising and futuristic substrate material for the growth of GaN, and it is foreseen that our results could be a reference for the further development of high performance nitride-based devices.

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. The independent piezoelectric constants d 11 and d 14 were measured by X-ray diffraction in the Bragg and Laue geometries. Excitation and propagation of surface acoustic waves 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.

The results of the investigation of multicomponent piezoelectric crystals of the group of galliumlanthanum silicate (langasite) are presented. The synthesis processes and the structure of crystals are investigated. The acoustic properties of the crystals are investigated using X-ray topography and diffractometry. The possibility of applying these piezoelectric crystals in high-temperature sensor devices based on surface acoustic waves is shown.

The X-ray optical properties of diffraction gratings fabricated on the basis of a Si(400) crystal with a period of D = 1 μm are studied by triple-crystal X-ray diffractometry. The diffraction gratings are manufactured both by silicon profiling during the process of plasma chemical etching and by forming a phase-shift grating on the surface of a Si crystal. The principal difference in the diffraction properties of these gratings is demonstrated. The presence of an Au phase-shift grating is shown to lead to the formation of a two-dimensional diffraction pattern, whereas Si profiling leads to the formation of only a one-dimensional diffraction pattern.

The process of the excitation and propagation of pseudosurface acoustic waves in crystals of the langasite family is studied via X-ray diffractometry for the first time. The investigations are carried out using the BESSY II synchrotron radiation source in the double-crystal X-ray diffractometer scheme. The process of pseudosurface acoustic wave propagation is studied based on an analysis of the diffraction spectra of acoustically modulated crystals. Both the velocities of the pseudosurface acoustic waves and the power flow angles of the acoustic energy are measured for the first time. The pseudosurface acoustic wave is shown to be flowing. Surface and pseudosurface acoustic waves generated by an interdigital transducer in the Z cut of a La3Ga5.5Ta0.5O14 crystal are compared.

A five-component crystal of the lanthanum–gallium silicate family Ca3TaGa3Si2O14 (CTGS) was grown by the Czochralski method. The CTGS crystal, like the langasite crystal (La3Ga5SiO14, LGS), 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 crystals grown by the Czochralski method. Surface acoustic wave (SAW) propagation in the CTGS crystal was investigated by the high-resolution X-ray diffraction method on the BESSY II synchrotron radiation source. The velocities of propagation and power flow angles of SAWs in the Y- and X-cuts of the CTGS crystal were determined from the X-ray diffraction spectra.

Ca3TaGa3Si2O14 (CTGS) crystals are a new promising material from the lanthanum-gallium silicate family, which can be employed in high-temperature sensors and other acoustoelectronic devices. The structural perfection and acoustic properties of CTGS crystals have been investigated via X-ray topography and diffractometry at the BESSY II synchrotron radiation source in the geometry of a double-crystal X-ray diffractometer.

A new promising piezoelectric material Ca3TaGa3Si2O14 (CTGS) has been grown using the Czochralski method. Its unit-cell parameters have been determined by means of the X-ray phase analysis method. The X-ray diffractometry method was used to study the crystal acoustic properties; the velocities of surface acoustic wave propagation were measured for the first time and the power flow angles were determined.

It is shown that the X-ray beam induced current method (XBIC) can be realized at the laboratory X-ray source using the polycapillary x-ray optics. The images of iron contaminated grain boundaries in multicrystalline Si are obtained. It is shown that the grain boundary XBIC contrast is 2-3 times smaller than the EBIC one. A simulation of XBIC and EBIC contrast values for two-dimensional defects is carried out and a good correlation between the experimental and calculated values is obtained. The dependence of grain boundary XBIC contrast on the X-ray beam width is calculated.

The features of formation of silicon structures with a periodically varying porosity are investigated by X-ray diffractometry. It is revealed that the magnitude of anode current density corresponding to the formation of a layer with higher porosity that is part of a multilayer porous structure also affects the porosity of a second, less porous layer. As time elapses, the single-crystalline matrix of which porous layers consist is amorphized and a structure consisting of amorphous layers with a periodically varying density arises.

Two nondestructive methods of X-ray lens testing—X-ray microtomography and phase contrast introscopy—are analyzed and compared. Refractive lenses fabricated via laser stereolithography are used as a comparative object. The first samples of photopolymer lenses have been created via the rotation method, in which a capillary filled with a Dikhrom Lyuks liquid photopolymer is exposed to UV radiation during centrifuge rotation. Lens samples have been fabricated at the centrifuge’s angular velocities lying in the range from 3000 to 5000 rpm. The features of photopolymer transition from the liquid state into the solid phase under UV irradiation have been investigated to estimate their influence on the formation of the required shape of a refractive profile.

The processes of the formation of domain structures in lithium tantalate crystals (≈300 μm thick) under electron irradiation in a scanning electron microscope were studied. Successive discrete quasi-point irradiations with an electron beam over the —Z-cut surface were used. This method of drawing by an electron beam made it possible to control the implanted charge and to examine the influence of the distances between conditionally point charges on the domain structure formed during switching. The effect of change in the direction of the beam displacement under irradiation on the domain-line width was investigated. The domain lattice with a period of 12 μm was formed on the —z face of the crystal, which transformed into a 2D-type structure deep in the crystal.

The dynamical theory based on Takagi-Taupin equations was used to model x-ray diffraction by the Z-cut of a LiNbO 3 crystal with short period regular domain structure. It found that the presence of even satellites on the x-ray diffraction spectra caused by the crystal lattice deformation. A proposed model of the deformation allowed us to achieve a very good agreement with the experimental data.

X-ray diffraction on a langatate crystal (La3Ga5.5Ta0.5O14, LGT) modulated by a Λ=12 μm Rayleigh surface acoustic wave (SAW) was studied in a double axis X-ray diffractometer scheme at the BESSY synchrotron radiation source. SAW propagation in the crystal causes sinusoidal modulation of the crystal lattice and the appearance of diffraction satellites on the rocking curves, with their number, angular positions, and intensities depending on the wavelength and amplitude of acoustic vibrations of the crystal lattice. Strong absorption of X-ray radiation in LGT enables the observation of the diffraction spectra extinction at certain SAW amplitudes. X-ray diffraction spectra analysis makes it possible to determine SAW amplitudes and wavelengths, to measure the power flow angles, and investigate the diffraction divergence in acoustic beam in LGT.

Congruent lithium niobate crystals with periodic domain structures formed by the method of thermoelectric postgrowth treatment have been investigated. Periodic domain structures in the samples of polar ZY-, YZ-, and YX-cuts were characterized by scanning electron microscopy, high resolution x-ray diffractometry, and topography. The evaluation and comparison of the secondary electron (SE) signal cycling, electron emission coefficient, and charge value to equalize the differences in the SE signal have allowed us to specify the features of ZY-and YZ-cut structures. A correlation between the crystal lattice distortions near domain boundaries and the type of domain walls has been found. The domain walls separating the areas with the tail-to-tail Ps vectors not only cause stronger crystal lattice distortions near them, but also are charged less quickly under electron irradiation.

Ca3NbGa3Si2O14 (CNGS), a five-component crystal of lanthanum-gallium silicate group, was grown by the Czochralski method. The parameters of the elementary unit cell of the crystal were measured by powder diffraction. The independent piezoelectric strain coefficients $$d{}_{11}$$ and $$d_{14}$$ were determined by the triple-axis X-ray diffraction in the Bragg and Laue geometries. Excitation and propagation of surface acoustic waves (SAW) were studied by high-resolution X-ray diffraction at BESSY II synchrotron radiation source. The velocity of SAW propagation and power flow angles in the $$Y$$ -, $$X$$ - and $$yxl/{+}36^\circ$$ -cuts of the CNGS crystal were determined from the analysis of the diffraction spectra. The CNGS crystal was found practically isotropic by its acoustic properties.

Bulk periodic domain structures created in LiNbO 3 crystal by the aftergrowth thermoelectrical treatment were studied by SEM and x-ray technique. Z and Y cuts, which have “tail-to-tail” and “head-to-head” domain walls, were comparatively investigated. In the SEM, a periodic domain contrast of the Z and Y cuts was studied and charge amount for equalization of the contrast was experimentally estimated. Special surface charging by an e-beam allowed the observation of domain contrast of highly distorted “tail-to-tail” domain walls. The SEM investigations were supported by x-ray results on crystal distortions near different domain walls.

The behavior of LiNbO3 and LiTaO3 crystals with domain structures in an external electric field was studied using high-resolution X-ray diffractometry and topography. Domain structures in Z-cut LiTaO3 and Y-cut LiNbO3 crystals have been formed by the aftergrowth thermoelectricall treatment technique were investigated. Strong elastic distortions near different domain boundaries in the Y-cut LiNbO3 crystal were detected. The possibility of using X-ray diffraction to measure piezoelectric charge constants tensor components is demonstrated.

X-ray topography is first used to totally examine the fundamental modes of acoustic oscillations in the bulk-acoustic-wave (BAW) resonator on the base of an AT-cut quartz crystal at the first and third harmonics. As is evident from the experiments, the anharmonic longitudinal oscillations of the resonator can be visualized, just as the fundamental transverse acoustic oscillations can be. The amplitude-frequency response (AFR) is related to the frequency dependence of diffracted x-ray intensity.

Pseudomorphic Si0.76Ge0.24/Si heterostructures grown by molecular-beam epitaxy were irradiated with 350-keV Ge+ ions at a temperature of 400°C so that the peak of the ions’ energy losses was located within the silicon substrate (deeper than the SiGe-Si interface). The effect of ion implantation on the relaxation of elastic stresses and the defect structure formed as a result of postimplantation annealing is studied. It is found that annealing at a temperature even as low as 600°C makes it possible to ensure a very high degree of relaxation of elastic stresses in the heterostructure and a comparatively low density of threading dislocations in the SiGe layer (

The dynamical theory was used to model X-ray diffraction by the YZ-cut of an LiNbO3crystal modulated by surface acoustic waves (SAWs). It includes both the calculation of the crystal lattice deformation, induced by a surface wave of Rayleigh type, and the simulation of X-ray wavefields in the crystal based on Takagi–Taupin equations. A detailed discussion is included on the effect of peak splitting occurring at high acoustic amplitudes. The developed theory entirely describes this effect and proves to be a powerful tool for understanding X-ray diffractometry and topography measurements by SAW-modulated crystals.

Results from using the current method, in which a current is induced by a focused X-ray beam (XBIC = X-ray beam induced current) on a laboratory source are presented. It is shown that by reducing the X-ray probe sizes and improving the resolution, there is a gain in contrast increase for obtained images of grain boundaries in a crystal.

X-ray diffraction on the X cut of a langasite crystal (La3Ga5SiO14) modulated by a Λ=12 μm Rayleigh surface acoustic wave (SAW) has been studied at the ESRF synchrotron radiation source. Due to the sinusoidal modulation of the crystal lattice involved by the SAW diffraction satellites appear on the rocking curve, with their number, angular positions, and intensities depending on the amplitude and wavelength of the ultrasonic superlattice. Full extinction of a specific satellite could be performed by adjusting the acoustic amplitude. It is shown that x-ray diffraction can be used to study surface acoustic wave field distributions in crystals.

Pseudomorphic Si0.76Ge0.24/Si heterostructures grown by molecular beam epitaxy were implanted with Ge+ ions at 400 °C in such a way that an ion-damaged region was located below the SiGe/Si interface. The effect of Ge+-ion irradiation on strain-relaxation rate and defect structure in the heterostructures was studied by transmission electron microscopy (TEM), X-ray diffraction (XRD), atomic force microscopy (AFM), and low-temperature photoluminescence (PL). It was found that annealing at a temperature as low as 600 °C resulted in very high degree of strain relaxation, while density of threading dislocations was low (

The effect of non-equilibrium point defects on strain relaxation in pseudomorphic Si 0.76 Ge 0.24 /Si heterostructures was studied by X-ray diffraction (XRD) and low-temperature photoluminescence (PL). The overcritical Si 0.76 Ge 0.24 layer was grown by molecular beam epitaxy at relatively low temperature in order to avoid strain relaxation during the growth and then the non-equilibrium point defect were introduced by Ge + ion implantation. The samples were annealed in the temperature range from 500 to 600 °C. The ion-irradiated heterostructures showed considerably different relaxation behavior than the unimplanted samples. For the same heat-treatment conditions, the degree of relaxation was found to increase as the implantation dose rose.

We examine the current state, prospects for development, and the application of X-ray optics at the IMT-IHPM: X-ray diffraction optics based on X-ray multilayer mirrors and crystals, X-ray acousto-optics based on X-ray diffraction by acoustically modulated crystals, and the application of X-ray methods of diagnostics for the investigation of piezoelectric crystals.

A five-component ordered crystal of lanthanum-gallium silicate family Ca3NbGa3Si2O14 (CNGS) was grown by the Czochralski method. The unit cell parameters were determined by using the powder diffraction technique. Independent piezoelectric strain coefficients d11 and d14 were measured by high-resolution X-ray diffraction under the external electric field application which caused changes in the interplanar spacing because of the reverse piezoelectric effect. Surface acoustic wave (SAW) propagation in CNGS crystal was investigated by X-ray diffraction method at the synchrotron radiation source BESSSY II. The velocities of SAW propagation and power flow angles were measured in the Y-, X-, and yxl/+36o-cuts of CNGS crystal.

X-ray diffraction on disordered La3Ga5SiO14 (LGS) and ordered Ca3TaGa3Si2O14 (CTGS) crystals modulated by surface (SAW) and pseudo-surface acoustic waves (PSAW) with wavelength of A=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, power flow angles of acoustic energy propagation.

The domain walls in LiNbO3 are studied using X-ray topography, X-ray diffraction, and scanning electron microscopy. It is shown that the regions of distortions of the crystal lattice near the domain walls of different types are different and have lateral sizes of 100–200 μm. The character and the magnitude of the distortions are substantially dependent on the method of formation of the domain structure. Under irradiation in a scanning electron microscope, the crystal region up to 25 μm in width near the “tail-to-tail” domain walls is charged more slowly and, unlike the “head-to-head” domain walls, exhibits a dynamic charge image in the secondary-electron regime.

Lithium tantalate crystals under the action of an external electric field have been studied by x-ray diffractometry. Both single-domain samples and crystals with a regular domain structure have been investigated. In the case of a single-domain crystal, the angular position of the Bragg peak varies under the action of an external electric field due to the reverse piezoelectric effect. According to this variation, the corresponding tensor component of piezoelectric constants can be calculated. In the crystal with a regular domain structure, a surface relief appears under the action of an external electric field. Piezoelectric constants can also be calculated using this relief.

Second generation of grazing-incidence-phase Fresnel zone plates is presented in this paper. The term grazing-incidence discrete Fresnel lens (GIDFL) for these zone plates is proposed. This lens performs a multilevel phase modulation of the incident X-ray radiation. With the increase of the number of levels, the GIDFL virtually becomes an ideal kinoform zone plate. X-ray optical properties of a four-level GIDFL are studied here. It is found that this lens is capable of focusing X-ray radiation with an efficiency of 75%. A model is proposed which describes the diffraction properties of these lenses and allows one to calculate the focal spot intensity.

Surface acoustic wave (SAW) propagation in a graphene film on the surface of piezoelectric crystals was studied at the BESSY II synchrotron radiation source. Talbot effect enabled the visualization of the SAW propagation on the crystal surface with the graphene film in a real time mode, and high-resolution x-ray diffraction permitted the determination of the SAW amplitude in the graphene/piezoelectric crystal system. The influence of the SAW on the electrical properties of the graphene film was examined. It was shown that the changing of the SAW amplitude enables controlling the magnitude and direction of current in graphene film on the surface of piezoelectric crystals.

The formation of fields of standing surface acoustic waves (SAW) in LiNbO/sub 3/ and La/sub 3/Ga/sub 5/SiO/sub 14/ (LGS) crystals was studied by high-resolution topography method on a laboratory X-ray source. The fields of standing SAW were formed using SAW-resonator structures consisting of interdigital transducer (IDT) and reflecting gratings. The SAW amplitudes and power flow angles were measured by X-ray topography, diffraction in acoustic beam was visualized, and the SAW interaction with the crystal structure defects was studied.

The result of X-ray diffraction study on a single crystal of the calcium-gallogermanate family Ca3TaGa3Si2O14 (CTGS) modulated by a surface acoustic wave (SAW) is presented. The power flow angle for SAW propagating along the X2 axis of the X-cut in CTGS was measured. The rocking curves for the CTGS crystal were recorded at different amplitudes of an input high frequency electric signal on interdigital transducer used to excite a SAW. Based on the data obtained, intensity dependence of diffraction satellites on the amplitude of electric signal exciting a SAW was built. Numerical simulation of the crystal rocking curves and dependence of diffraction satellite intensities on the SAW amplitude enabled the selection of a set of material constants at which the most complete coincidence of experimental and calculated results is observed.

X-ray diffraction on the crystal La3Ga5.5Ta0.5O14 modulated by surface acoustic waves (SAW) and pseudo-surface acoustic waves (PSAW) with wavelength of Λ=8 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 which propagates at an angle to the crystal surface.

X-ray Bragg diffraction on an acoustically modulated La3Ga5SiO14 crystal (langasite, LGS) was studied in the saggital geometry where a surface acoustic wave (SAW) serves as diffraction grating of normal incidence. A set of parabolic compound Be refracting lenses was used to focus x-ray radiation in order to obtain good angular and spatial resolution of diffraction satellites. X-ray diffraction spectra analysis provided information on the acoustic properties of the LGS crystal and enabled the determination of SAW amplitudes and wavelengths.

The x-ray beam induced current method (XBIC) is realized on the laboratory x-ray source using the polycapillary x-ray optics. It is shown that rather good images of grain boundaries in Si can be obtained by this method. The parameters of x-ray beam are estimated by the simulation of Schottky diode image. A good correlation between the experimental and calculated grain boundary XBIC contrast is obtained. The possibilities of laboratory source based XBIC method are estimated.

In present paper we report the fabrication process of a high-temperature SAW-sensor based on a langasite crystal. Interdigital transducers of the SAW-resonator structures were fabricated from Ir which was evaporated using magnetron sputtering technique. The SAW-sensors were designed with different coefficient of metallization of an IDT, which strongly influences on the value of the SAW velocity and resonance excitation frequency, respectively. The process of the SAW excitation was investigated using high-resolution X-ray diffraction technique