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Tunable 5.2 GHz bulk acoustic wave resonators utilizing BaxSr1-xTiO3 ferroelectric films with similar intrinsic properties but different interface roughness are fabricated and characterized. Increase in roughness from 3.2 nm up to 6.9 nm results in reduction in Q-factor from 350 down to 150 due to extrinsic acoustic losses caused by wave scattering at reflections from rough interfaces and other mechanisms associated with roughness. The increased roughness is a result of distortion of Pt bottom electrode caused by formation of heterogeneous enclosures of TiO2-x in the Pt layer. [ABSTRACT FROM AUTHOR]

Current and voltage noise measurements have been carried out on nanoparticle WO[sub 3] films. The fluctuation dissipation theorem holds, which indicates that the observed noise is an equilibrium phenomenon. Results on the thinnest films show that noise measurements can be used for quality assessment of nanocrystalline insulating films. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Advanced gas deposition was used to produce nanocrystalline gold films under conditions giving four different deposition rates. Grain growth and structural modification of the grain boundaries were probed during annealing by use of in situ electrical transport measurements. Time dependent resistivity data were fitted to a relaxation model whose activation energy went up upon increased isothermal annealing temperature. The grain boundary transmission coefficient for the samples scaled, up to a certain limit, with the deposition rate; this is believed to be due to a higher concentration of pores, or a wider grain boundary region containing a disordered structure, in samples prepared at low deposition rates. Such samples also displayed enhanced thermal stability with negligible grain growth up to 773 K upon annealing in vacuum for 2 h. Samples prepared above this limit, at the highest deposition rate, exhibited a decreased grain boundary transmission coefficient. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Reports on thin transparent tin oxide films doped with oxygen vacancies, antimony, fluorine or molybdenum. Experimental setup for the preparation of the films; Process optimization for optical and electrical properties; Analysis of the optical data; Film characterization with x-ray diffraction and transmission electron microscopy.

Studies the influence of the substrate morphology in YBa[sub2]Cu[sub3]O[sub7-x] thin films on yttria-stabilized ZrO[sub2] substrates. Details on the experiment; Results of the study; Discussion of findings.

Analyzes the structural and electrical characterization of epitaxial thin films. Details on the experimental techniques; Results of the study; Conclusions.

Describes the electromagnetic properties of YBa[sub2]Cu[sub3]O[sub7] (YBCO) step edge junctions and the microstructures of YBCO thin films grown on straight and wavy step edges on (001) LaAlO[sub3] (LAO) substrates. Information on the YBCO grain boundary; Factors to consider before growing a YBCO film; Technique used to study the microstructure of the YBCO film across the straight and wavy step edges on (001) LAO substrates.

Intrinsically tunable 0.67BiFeO3-0.33BaTiO3 (BF-BT) thin film bulk acoustic wave resonators with record high tunability of 4.4% and effective electromechanical coupling coefficient of 10% are fabricated and analyzed. The analysis, based on the theory of the dc field induced piezoelectric effect with the mechanical loading by the electrodes taken into account, reveals that the enhanced parameters are associated with the inherently high BF-BT electrostriction coefficient, which is found to be 5.9 × 1010 m/F. The Q-factor of the BF-BT resonators is up to 220 at 4.1 GHz and is limited mainly by acoustic wave scattering at reflection from a relatively rough top interface. [ABSTRACT FROM AUTHOR]

The ability to control optical effects at the nanoscale is a challenge that could be of great importance for a range of photonic applications. However, progress requires a deep understanding of the relationship between near-field and far-field properties of the individual elements of the nanostructure, as well as of the role of nano-optical interactions. Here, we show that the strong interaction between nanoholes in optically thin metal films can be used to readily tune their spectral response and visibility. Control of this interaction in short chains of nanoholes enables either amplification or almost total suppression of the scattered light. The phenomena are interpreted in terms of hole coupling mediated via antisymmetric surface plasmon polaritons, which makes the nanohole chains effectively behave as linear wire antennas. [ABSTRACT FROM AUTHOR]

Studies crack formation in epitaxial [110] thin films of YBa[sub2]Cu[sub3]O[sub7gamma] and PrBa[sub2]Cu[sub3])[sub7x] on [110]SrTiO[sub3] substrates. Lattice parameters and orientation; Crack spacings along the [001] direction as a function of deposition temperature and film thickness; Characterization of typical microstructures of the film.

Examines the elimination of pinholes in epitaxial thin film multilayers. Introduction of SrTiO[sub 3] (STO) and PrGaO[sub 3] intermediate layers; Deposition of YBa[sub 2]Cu[sub 3]O[sub 7-x] films on the (001) STO substrate; Characterization of microstructures using several electron microscope instruments.

Examines the use of KTaO[sub 3] for microwave applications. Combinations of high transition temperature superconducting and ferroelectric films; Growth of c-axis oriented YBa[sub 2]Cu[sub 3]O[sub 7-delta] (YBCO) films; Deposition of YBCO films on KTaO[sub 3].

Abstract: The microstructure of silver-containing indium tin oxide (ITO) films, deposited by sequential reactive direct current (DC) magnetron sputtering of ITO and Ag, was investigated by transmission electron microscopy (TEM) with selected area electron diffraction, high resolution TEM, energy dispersive spectroscopy, and energy-filtering TEM (EFTEM). All films had a columnar structure with (222) texture. The silver additive did not alter the ITO grain orientation, even though the columnar size of the ITO grains was decreased slightly when the silver content was increased. Nanoparticles of silver, with sizes ranging from 2 to 5 nm, were distributed in layers, as demonstrated by EFTEM using the Ag M4,5 peak. The influence of the silver deposit on the microstructure and properties of the ITO films is discussed. [Copyright &y& Elsevier]