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Examines the initial kinetics of surface-energy-driven grain growth (SEDGG) in silicon that occurred during rapid thermal annealing. Description of the SEDGG; Fraction of the area of a thin film transformed to secondary grains; Definition of extended fraction.

Deals with a study which investigated the mechanical properties of nanocomposite Ag-Al[sub2]O[sub3] and Fe-SiO[sub2] granular metal films by low-load indentation and laser ultrasonic methods. Film preparation and microstructural analysis; Mechanical testing methods; Results and discussion.

Presents a study on the mechanical properties of silver-Al[sub2]O[sub3] and nickel (Ni)-Al[sub2]O[sub3] granular metal thin films as well as the magnetic behavior of the Ni-based films. Enhancements in the mechanical properties of the materials; Hardness behavior of Ni-Al[sub2]O[sub3] films; Results concerning the magnetic ordering temperature of the samples.

Presents information on a study that discovered that the apparent expansivity of nickel/copper multilayers was found to depend on the interface densities in the multilayers. Experimental techniques; Results of the study; Conclusion.

Magnetic nano-network structure has been fabricated by electrochemical deposition Ni onto laser modified Au film. Scanning electron microscopy images show that the network has a three-dimensional interconnecting branch structure with branch diameter of about 100 nm, constructed from grains with diameter of about 25 nm. Because of this structure, the Ni network has enhanced coercivity, in-plane isotropy, and a combination of longitudinal and transverse anisotropic magnetoresistance. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Hiperco®50 alloy heat treated between 450 and 650 °C exhibits superior mechanical properties. We report the measurements of the ac core loss at various frequencies up to 4500 Hz of the Hiperco®50 alloy samples annealed at 450 and 650 °C. The 650 °C annealed specimens have lower ac core loss than that of the 450 °C annealed ones. The total core loss, consisting of contributions from hysteresis core loss and eddy-current core loss, depends on frequency f as af+bf [SUP2]. The eddy-current loss of a single laminate is minor compared to the hysteresis loss. [ABSTRACT FROM AUTHOR]

Hiperco[sup ®] FeCoV alloys are soft magnetic materials suitable for applications at high temperatures and under high stresses. We have studied the evolution of the rolling texture and its effects on the mechanical and magnetic properties after annealing the Hiperco[sup ®] sheets at high temperatures. X-ray pole-figure measurements reveal that the main texture of the as-rolled HA50HS and HA50 sheets is {001}<11¯0>. This rolling texture causes the mechanical and magnetic properties to exhibit a uniaxial anisotropy, which is reduced by annealing. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The effects of acetic acid, tartaric acid, and Pb-mediated underpotential deposition (UPD) on the filling characteristics of copper electrodeposition in sub-micron trenches were studied. In the absence of other electrolyte additives, potentiostatic and galvanostatic depositions from electrolytes containing organic acids were capable of producing dense filling in sub-micron trenches due to higher deposition rates at the trench bottoms compared to the side-walls and adjacent surfaces surrounding the recessed features. The mechanism for dense filling of trenches from depositions in the organic acid containing electrolytes did not appear to match previously identified mechanisms for superfilling associated with surfactant effects. Instead, the differential deposition rates across the trench profile were attributed to textural and/or structural differences in the copper seed layer as the copper deposition rates were enhanced at both the bottom and adjacent surfaces surrounding the trenches, or sidewalls of the trench depending on the organic acid species present in the electrolyte. The organic acids induced conformal and smooth depositions improving with increasing overpotential. Pb mediated UPD yielded smooth, conformal films relative to non-mediated deposition under otherwise identical conditions. The density of the UPD mediated films was best at higher Pb coverage during Cu deposition. [ABSTRACT FROM AUTHOR]

Gibbs formulated a complete and general thermodynamics for surfaces in multicomponent fluid systems. When considering solid-fluid surfaces, he restricted attention to single-component solids in contact with fluids that could contain multiple components. Attempts that have been offered to generalize Gibbs' results for surfaces between multicomponent solids and fluid are problematic owing to the difficulty that the surface chemical potentials for components that also reside on substitutional lattice sites in the solids are not well defined. Therefore any expressions involving these surface chemical potentials, such as the conventional definition of the surface energy, will also not be well defined. In order to formulate a general thermodynamics of equilibrium that takes into account capillary effects in systems containing surfaces between a multicomponent solids and fluids, it is shown that the concept of thermodynamic availability (exergy) can be employed that, when applied to surfaces, depends on the extensive but not the intensive variables (such as the chemical potentials) of the surfaces. Using this approach, Gibbs-Thomson-Freundlich effects for finite-size solids, an adsorption equation for solid-fluid surfaces and the thermodynamics of nucleation during solidification can be treated in a straightforward manner without referring to the ill-defined surface chemical potentials. A derivation is given that appears to be the first one that properly generalizes Gibbs' analysis for the reversible work to form a critical nucleus to the case of solidification. [ABSTRACT FROM AUTHOR]

High aspect ratio Fe0.55Co0.45 alloy nanowires were fabricated by electrochemical deposition from sulfamate solution into nanoporous templates with diameters between 20 and 200 nm and lengths up to 6 µm. The capability to fill narrow (down to 20 nm in diameter) and deep (micrometer size) pores with high magnetic flux density Fe-Co alloys makes it a potential candidate for deposition of the writer poles in hard disk drives. The deposited nanowires were polycrystalline with a grain size of about 10-40 nm. Strong magnetic shape anisotropy is characteristic of the deposited high aspect ratio Fe-Co nanowires. The saturation magnetization of the nanowires was about 22-24 kG, in excellent agreement with values reported for bulk Fe-Co alloys. For nanowires with diameters in the range from 30 to 100 nm, magnetic reversal is shown to be consistent with the curling model. [ABSTRACT FROM AUTHOR]

Presents a study that developed the mechanics of thin film epitaxy using an equilibrium thermodynamics formalism and linear elasticity. Discussion on the issues involved in determining the equilibrium coherency stress and strain states of the film; Presentation of the thermodynamic system; Conditions for equilibrium; Assessment of critical film thickness.

The equation of motion for a one-dimensional inhomogeneous medium is derived using the Lagrangian description of a continuous medium. The equations of motion are determined from the Euler-Lagrange equations derived from the Lagrangian density. A general form of the solution is obtained and the specific solution for the special case of a medium whose elastic stiffness changes linearly with distance in the propagation direction is determined. The displacement field is calculated for this case showing the effects of the inhomogeneity on shape and signal velocity of elastic pulses. [ABSTRACT FROM AUTHOR]

We describe a method of precision transport of nanowires in suspension using a combination of dielectrophoretic force and electrophoretic force, which, respectively, aligns and transports the nanowires. The transport of nanowires can be made to follow any prescribed trajectory with any orientation by the voltages applied to the patterned electrodes. The same method applies to multiwall carbon nanotubes as well. We have joined end to end two oppositely charged nanowires separated by 200 μm into a microelectromechanical device. [ABSTRACT FROM AUTHOR]

The authors report a versatile and efficient method for assembling nanowires in suspension into scaffolds using ac electric fields. The electric field and its gradient aligns and transports, respectively, the nanowires into scaffolds according to the electric field distributions. The assembling efficiency strongly depends on the frequency of the applied ac voltages and varies as square of the voltage. The assembly morphology is highly influenced by the frequency regardless of applied voltages. [ABSTRACT FROM AUTHOR]

The epitaxial growth of InAs nanowires on an InAs(111) substrate in a sealed quartz tube is described. The method is quite simple and fast, and uses only a bare InAs substrate and a gold colloid coated InAs(111) substrate. High quality InAs nanowires can be produced by this technique, with the nanowire diameter controllable by the variation of growth temperature. The composition of the seed particle at the tip of the nanowire indicates that the nanowires grew via the vapor-liquid-solid growth mechanism but with Au–In as the liquid alloy. [ABSTRACT FROM AUTHOR]