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The thickness dependence of microstructures of La0.8Ca0.2MnO3 (LCMO)/SrTiO3 (STO) thin films was investigated by high-resolution x-ray diffraction, small angle x-ray reflection, grazing incidence x-ray diffraction, scanning electron microscopy, and atomic force microscopy. The results show that all the LCMO films are well oriented in (00l) direction perpendicular to the substrate surface. Self-organized crystalline grains with a tetragonal shape are uniformly distributed on the film surface, indicating the deposition condition being of benefit to the formation of the crystalline grains. With increasing the film thickness, the crystalline quality of the LCMO film is improved, while the surface becomes rougher. There exists a nondesigned cap layer on the upper surface of the LCMO layer for all the samples. The mechanism is discussed briefly. [ABSTRACT FROM AUTHOR]

The microstructures of amorphous LaAlO3 thin films deposited on silicon substrates by the laser molecular-beam epitaxy were studied by the x-ray reflectivity and the angle-resolved x-ray photoelectron spectroscopy. It was shown that the film/substrate interface contains a La-rich LaxAlyOzSi layer and a SiOx layer. It was shown that the electron density of the LaAlO3 layer and the LaxAlyOzSi layer is not homogeneous along the growth direction due to the diffusion of La, Al, and Si. The growth kinetics of the LaAlO3 film was described by three processes: (1) formation of the SiOx layer at the early stage whose thickness saturates rapidly at about 13 Å; (2) formation of the LaxAlyOzSi layer by the out diffusion of Si and the inner diffusion of La, Al (mostly La). This stage continues as the film grows (3) In the deposition process of LaAlO3, the distributions of La and Al in the LaAlO3 layer change from inhomogeneous to homogeneous. [ABSTRACT FROM AUTHOR]

Elemental distributions of Ni, Mn, and Co nearby the interfaces of sputtered ultrathin NiMn/Co multilayers have been investigated by x-ray anomalous scattering. In the direction normal to the film, the elements Ni, Co, and Mn are observed to vary gradually at the Co/NiMn interface with each element having a different distribution. After the samples were annealed at 300 °C for periods of 3, 10, or 20 h, the elements are observed to vary gradually at the NiMn/Co interface, as well. To obtain information on the in-plane distribution of each element at the interfaces, x-ray diffuse scattering experiments were performed with x-ray energy close to the Ni, Co, and Mn K edges. Different geometrical interfacial correlated roughness is observed with different x-ray energy. [ABSTRACT FROM AUTHOR]

The scanning tunneling microscope (STM) was used for both spot coloring and bleaching on α-WO[sub 3-x] thin films. By wetting the STM tip with 1 M KOH solutions or de-ionized water before the tip approached, and keeping the humidity higher than 40%, the electrochemical reaction occurred at the tip–surface gap while the electrochromic reactions took place at the film surface. With a constant negative sample bias and grounded tip, a brown color circle or a light blue disk was formed on the surface with an enlarged diameter. The circle and disk formations were attributed to the production of alkali and hydrogen tungsten bronzes. By applying a positive sample bias with a grounded tip, the color of the hydrogen tungsten bronze could be bleached. The cathodic reduction of W[sup 6+] forms a color center at the W[sup 5+] site, while the anodic reaction removes an electron from the color center W[sup 5+] state. Raman spectroscopy indicated that for the colored state, the frequency for the W–O bond stretching mode increased, while for the W==O bonds it decreased. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Presents a study which performed theoretical simulations of x-ray double-crystal diffraction rocking curves for strain-relaxed superlattices based on x-ray dynamical diffraction theory. Details on calculations of rocking curves; Description of the model structure used for the calculation; Method used in preparing InGaAs, gallium arsenide, GeSi and silicon superlattices.

Presents a study which investigated the Si[sub1-subx]Ge[subx]/Si strained-layer superlattices grown by molecular beam epitaxy on silicon substrates by x-ray double crystal diffraction and x-ray grazing incidence diffraction. Components of the superlattices; Discussion on lattice relaxation; Results of double-crystal diffraction.

Investigates the effect of a surfactant on the growth of germanium-silicon (Si)/Si superlatticces using x-ray reflectivity. Solution for partially self-affine interface structure with isotropic height-height self-correlation functions; Calculation of the transmission and reflection of x-rays at an interface; Overview of the interface morphology in superlattices.

Provides information on a study that presented the magnetic properties of iron/palladium multilayers prepared by ultrahigh vacuum electron-beam evaporation. Experimental procedure; Results and discussion.

Deals with a study which examined the surface roughness of indium phosphide wafers by X-ray reflexivity and crystal truncation rod (CTR) measurements. Determination of the root-mean-square roughness and the lateral correlation scale; Components of the scattering intensities in the scans transverse to the specular reflection rod; Discussion on the sensitivities of the methods to the surface structure and the role of the resolution functions in the CTR measurements.

Elemental distributions of Fe, Mn, and Co in ultrathin FeMn/Co multilayers have been profiled by the x-ray anomalous scattering technique. Chemical intermixing is observed at the FeMn/Co interfaces with intermixing regions up to 14 Å. The chemical compositions in the intermixing regions are found to vary gradually from FeMn to FeMnCo[sub 2] and from FeMnCo[sub 2] to Co., respectively, but not from FeMn to Co. This result suggests that a reaction may occur and FeMnCo[sub 2] appears at the interface during the deposition. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Focuses on a study which investigated a microstructure of an A[sub1]Ba[sub2]-type ZnSTe/ZnSe quantum structure by x-ray two-axis diffraction and x-ray topography. Theoretical background; Description of the experimental setup; Findings.

Reports on the simulation of interference effects in the x-ray double-crystal rocking curves of Ge[subx]Si[sub1-x]/silicon strained-layer superlattices (SLS) on the x-ray dynamical scattering theory. Diffraction rocking curve of a nominal SLS sample.

Presents information on a study that examined the effects of annealing on the properties of magnetic granular CoCu alloy ribbons that were prepared by the melt-spun method. Research method; Results and discussion.