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The differences in the secondary processes proceeding in the silicon layer of SOI and reference bulk silicon wafers are revealed by using High-Resolution X-ray diffraction and Rutherford Backscattering spectroscopy methods. The damage depth profiles in the implanted layers described by both strain and static Debye-Waller factor profiles, were reconstructed from the diffraction patterns using an autofitting procedure, based on a genetic algorithm. The contribution of diffuse scattering was excluded using the triple-crystal diffractometry technique. The defect density profiles were obtained from the RBS/Channelling measurements, which were carried out using 4 He + beam at 2.0 MeV. The DICADA code, based on the theoretical description of dechanneling was used to interpret the RBS/C data. Accumulation kinetics, spatial distribution, and concentration of radiation-induced defects in the topmost silicon layer of SOI and a bulk silicon were shown to be essentially different. The influence of the fields was shown to lead to the loss of crystallinity of the thin surface layer of silicon in SOI due to accumulation of vacancy-type defects and increase of concentration of interstitial atoms near the internal interphase boundary "Si-SiO 2 ".

The combinatorial method, which was exclusively employed for the drug discovery until recently, has invaded the field of inorganic materials and is becoming a key technology in materials science today. Phosphors, with their diversity of possible mechanisms of luminescence, represent a typical example of a field where the combinatorial approach promises to be especially fruitful. Here, we present the results of systematic combinatorial exploration of different binary and ternary ZnO:dopant systems, which resulted in identification of bright luminescence in ZnO:(Y,Eu), ZnO:V, ZnO:W, and ZnO:(W,Mg) systems. Careful “zooming in”, i.e., fabrication and screening of more detailed libraries near the identified promising compositions, allowed us to find optimum phosphor compositions for the above-mentioned systems. The efficiency of the new phosphors in low-voltage cathodoluminescence is high and promises their prospective use in advanced flat panel display and lighting applications.

High-resolution X-ray diffraction (HRXRD), X-ray reflectometry (XRR), X-ray photoelectron spectroscopy (XPS), and Atomic-force microscopy (AFM) were used to study the influence of the chemical activity of implanted ions (N+, O+, F+ or Ne+) on the structure of the damaged Si layer in SIMOX substrates. The implantation conditions were chosen so that the number of primary defects and the projected range were approximately the same for the implanted ions. HRXRD showed that the depth distribution of the residual damage depends on the chemical activity of the impurity. This may result from the quasi-chemical interaction between the radiation-induced point defects (VSi and Sii) and the impurity atoms. The shape of the density profiles and the thickness of the transition surface layer obtained from the XRR data are different for the implanted ions. The [100] faceted surface features of the samples prepared by SIMOX technology are preserved after implantation with the ions. AFM revealed a reduction of the lateral correlation length. The magnitude of this effect depends on the chemical activity of the implanted ions. Silicon oxidation at a depth of 10–15 nm is shown by XPS to change depending on the implanted ion.

Graphite intercalation compounds containing cesium and oxygen were synthesized and isolated for the first time. The interplanar distance is 9.84 A.

Cette methode fournit un plus grand nombre d'informations comparee aux procedures des cristaux doubles et triples traditionnelles. Sous les conditions experimentales donnees, il n'est pas possible d'observer la dynamique de contrainte elastique dans le cas d'une implantation integrale

Intercalation of potassium superoxide KO 2 into graphite in the presence of potassium metal was studied. Graphite intercalation compounds of stage 1 (assigned formula C 4 KO 2 , c -axis repeat distance 8.44 A) and stage 2 (assigned formula C 8 KO 2 , c -axis repeat distance 11.75 A) were synthesized and isolated for the first time. A quadruple intercalate layer KOOK is supposed. In-plane structure of the intercalate layer is discussed mostly on the basis of X-ray diffraction intensity analysis and transmission electron microscopy electron diffraction. A metal-like temperature dependence of c -axis resistivity was obtained in the 1.5–300 K temperature range where the resistivity values at room temperature are 0.07 and 0.81 Ω cm for stage-1 and stage-2 compounds, respectively. The results of magnetic susceptibility measurements suggest that the oxygen species are in nonmagnetic states.

Recent advances in fumigation technique in the USSR are reviewed. The problem of fumigation in containers is being approached by introduction of the gas through air-holes. Mixtures of methyl bromide with carbon dioxide are being used increasingly against storage pests, and allow lower dosage rates and safer application conditions. Recent experience on quarantine fumigation of potato tubers against Phthorimaea operculella is reviewed, and finally research is reported on neutralizers and absorbents of methyl bromide used to facilitate degassing.