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A detailed characterization of the structural changes induced by xenon preamorphizing implant (PAI) treatment on ultralow energy arsenic-implanted (001) silicon is described. It is observed that end-of-range defects, present after implant below the amorphous-to-crystalline interface, transform from small Si interstitial clusters to dislocation loops during annealing depending on the implant conditions.

The type, length, and width of the 311 defects created with different times during the annealing of an ion-beam-doped Si are measured using grazing-incidence x-ray scattering. The results agree well with computer simulation predictions and transmission-electron-microscopy measurements, demonstrating that x-ray methods can be used as a nondestructive, rapid method to characterize the 311 defects.

Research was conducted to study the structure factor of diffuse scattering and amorphous scattering in W/Si multilayer under the simultaneous excitation of x-ray standing waves. The dynamically broadened first multilayer Bragg peak was modeled by the Darwin theory of dynamic diffraction while the decay of diffuse intensity was determined in a grazing incidence geometry. Results showed that the phase shifts can be computed without using the recursive matrix technique.

Multilayers for the water window region of the soft x rays have been prepared by pulsed laser ablation with amorphous [Ni.sub.50][Nb.sub.50] and amorphous C. The structural characterization of the multilayers, period d = 2.41 nm, shows that the interfaces are sharp with a roughness of only 0.4 nm that is chemical, not morphological, in origin. The interface roughness was found to be uncorrelated in the direction normal to the plane of the film. The normal incidence soft-x-ray reflectivity of the multilayer at 4.85-nm wavelength is 0.06%, 1 order of magnitude lower than the theoretically predicted value. However, the resolution limit [Lambda]/[Delta][Lambda] of the multilayer was found to be 16.7, close to the theoretically predicted value. Key words: Soft x rays, multilayers, x-ray microscopy.

An in situ combination of atomic force microscopy and micro x-ray diffraction was developed to study the elastic behavior of nanosized objects such as a single self-assembled 450 nm high SiGe island. The pressure required to compress the island lattice to the Si value amounted to about 3 GPa and was found to be in good accordance with finite-element method simulations of the displacement field in the pressurized object.

Nanogranular Co/Cu multilayers made of thin fragmented Co layers separated by thicker Cu layers are deposited in order to analyze how the structure and the microstructure of magnetic nanogranular samples have changed as the average particle size is reduced and how these changes have affected the giant magnetoresistive response of the samples. The diffraction measurements have shown that the degree of structural disorder has increased by decreasing the thickness of the Co layers.

The effect of the reduction of the magnetic layer thickness on sample correlated roughness in Co/Cu granular samples produced through the incomplete layer method is examined. The fragmentation process has promoted conformal nanoscale roughness and has lowered the giant magnetoresistance response of the system.

Diffraction method is used for examining the structure of polycrystalline [Ni.sub.3]N layers in periodic C/Ni multilayers, where the method is modulated by a standing wave created by the interference of the radiation. This method is used for analyzing the profiles of the crystallize sizes and strains in multilayers.

A study examines the stoichiometry, structure, and defects of slef-assembled heteroepitaxial Ge nanodots on twin-free type B oriented cubic [Pr.sub.2][O.sub.3](111) layers on Si(111) substrates. Results indicate that mutually isolated hemispherical Ge nanocrystals can be grown on cubic [Pr.sub.2][O.sub.3](111)/Si(111) support systems.

A new synthesis method for preparation of thin films and powders consisting of zeolite beta nanocrystals embedded in ordered mesoporous silica matrix is described. It is shown that the incorporation of beta nanocrystals in the mesoporous silica matrix and the mesophase order itself can be controlled through the variation of the fractional amounts of the zeolite nanoparticles and silica/surfactant solutions.

Studies the structural assembly of Cd-arachidate molecules in multilayers. Formation of a layered structure on the substrates revealed by the grazing incidence x-ray reflection studies; Results of reflectivity simulations; Interface roughness.

Ordering of colloidal Co nanoparticles on various types of substrates by grazing-incidence and scanning electron microscopy was studied. Results revealed that it is possible to improve ordering of nanoparticles over larger areas by choosing a flat substrate.

Growth and dissolution of near-surface defects after boron implantation in silicon is investigated. The nature and kinetic behavior of the implantation induced defects is revealed.