Structure distortions appearing near the surfaces of crystals irradiated by high energy ions (H, Kr, U) accelerated till energy of several MeV using respectively the accelerator U-120 (Kiev, Ukraine), the heavy ions accelerators (Caen, France and Darmstadt, Germany) were investigated by means of various X-ray diffraction methods (topography and diffractometry). Nonhomogeneous distribution of lattice distortions near the surfaces of irradiated crystals were discovered using these methods in all of the samples. Besides the barrier zones where the accelerated ions stopped, the wide distorted regions situated nearer the surface were found. The fine structure of different zones, their extents as well as the level of static Debye-Waller factor were determined. The depth distribution of this factor was compared with the results obtained by using the edge contrast measurements some years ago. This permitted us to draw conclusions about some relaxation of elastic strains in the interference regions after many years.

The structural perfection of Czochralski grown silicon crystals annealed at 1580-1620 K under hydrostatic pressure up to 10 9 Pa was investigated by X-ray diffractometry and topography supplemented by the method of absorption of infrared rays. Such treatment suppresses dissolution of oxygen--related defects. From the static Debye-Waller factor dependence on the reflection order it was concluded that large clusters or dislocation loops are the dominant type of defects for most of the samples.

A diffractometrical method for quantitative evaluation of structure perfection level in silicon single crystals containing various types of near surface distortions is described. The method is based on the spatial distribution analysis of the reflected intensity in the Bragg case of diffraction. To implement the proposed approach one has to satisfy the condition of the so-called low X-ray absorption because in this case the penetration depth of diffracted radiation exceeds the corresponding value of extinction length. It permits us to obtain a remarkable value of noncoherent reflectivity due to defects placed in deep (on the extension of absorption length) regions of a crystal and therefore, to increase the sensitivity of scattering for low distortions of crystal lattice. Using the method described here the extension of various disturbed layers as well as the level of the static Debye-Waller factor of a crystal can be determined. The effect of surface distortions caused by mechanical treatment and the influence of the following thermal annealing as well as irradiation by high energy protons on the defective structure of the samples were investigated.PACS numbers: 81.40.-z, 61.10.-i X-ray diffractometry based on determination of the integral characteristics (i.e. averaged over a scattering volume) of defect stuctures is one of the most effective methods for diagnostics of real single crystals. Now the nondestuctive methods of rapid stucture perfection control are developed and widely used in scientific and industrial laboratories. The methods, in particular, permit us to identify the type of predominate defects distributed homogeneously over the bulk of a crystal as well as to determine their mean dimension and concentration [1, 2].(309)

A new approach to structure perfection diagnostics of dislocation-free silicon crystals has been developed using the Bragg case of diffraction. The approach is being based on successive measurements of integral reflectivity and the spatial intensity distribution of reflected beam on the same diffraction planes of a real crystal by means of a single crystal diffractometer.

A new approach to determination of microdefect structure parameters by means of single crystal diffractometer is proposed. The approach is based on the measurements of the integral reflectivity of a sample for two selected X-ray wavelengths providing with the approximations of thin and thick crystal, respectively.