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The dc-dc converter is a critical component in a hybrid electric vehicle since it supplies power to an electronic control unit, as well as chassis electric components such as power windows, wipers, etc. In this paper, a low-cost diagnostic method for MOSFET faults in a zero-voltage-switching dc-dc converter is proposed. The proposed method utilizes the dc-link current patterns as the signatures of faults of MOSFETs. A presignal processing circuit consists of a peak detector and an integrator circuit. The ratio of peak-to-integral values, which is similar to the crest factor, is useful for diagnosis. Index Terms--Crest factor, dc-dc converter, fault diagnosis, MOSFET.

Stoichiometric (Ba0.5Sr0.5)TiO3 (BST) thin films with different thicknesses were produced on Pt/SiO2/Si substrates utilizing the conventional radio frequency magnetron sputtering technique with a ceramic target containing excess BaO and SrO. With increasing film thickness, the grain size of the BST films gradually increased. The dielectric constant increased from 348 to 758 when grain size increased from 32 to 82 nm in BST films deposited at 600 degrees C.

The influence of heat treatment on SrTiO3 thin films prepared by radio frequency magnetron sputtering was investigated. The results showed that three regions made up the thin films: an external surface layer, a main layer and an interface layer. Annealing at temperatures below 600 degrees celsius did not have any effect on the composition and width of the interface layer. However, annealing exerted a high degree of control over the electrical characteristics of the films.

The electric field-temperature phase diagram of Zr0.98sn0.02TiO4 is presented and examined using X-ray diffraction methods. The existence of commensurate phases corresponding to the rational values 1/21 and 1/23 for the incommensurate deviation factor were confirmed through accurate satellite position measurements. Results are discussed qualitatively in the light of Aubry's and Landau's 'devil's-staircase' approaches.

X-ray research shows that the electric files in the incommensurate phase transition in ZrTiO4 ceramic increasing dc electric field current results in rising normal incommensurate phase transition temperature (dTi/dEi) which are approximately equal to +1.7 degrees centigrade centimeters/kV. Electric field-temperature phase analysis is performed.

The germanium films were deposited on TiAlN bottom electrode at various temperatures by metal organic chemical vapor deposition using Ge(allyl)4(Ge(C3H5)4) and Sb(iPr)3(Sb(C3H7)3) precursors. Deposition of germanium films was only possible by a catalytic role of Sb metal by a thermal decomposition of Sb(iPr)3(Sb(C3H7)3) precursors. Deposition rate of the Ge films increases with increasing Sb bubbling temperature at a substrate temperature of 370 °C. The deposition characteristics of Ge films were controlled by a surface reaction in the temperature range from 360 to 380 °C and were controlled by a mass transport in the range of 380–400 °C. The step coverage of Ge films in 500×200 nm2 trench structure was approximately 93% at a substrate temperature of 370 °C. [ABSTRACT FROM AUTHOR]

Presents a study which prepared polycrystalline Pb(Zr[subx]Ti[sub1-x])O[sub3] (PZT) thin films on p-type silicon wafers by the metalorganic chemical vapor deposition process. Materials and methods used; Details on the x-ray diffraction and microstructural analyses of PZT thin films with different deposition temperatures; Effect of the compositional ratio between zirconium and titanium on PZT structure.

Presents a study that examined particle size dependence of the dielectric and piezoelectric properties of ceramic-polymer composites. Determination of the thickness of the surface layer of the composites; Calculation of the dielectric constant of the composites; Analysis of the hysteresis loop of the composites.

A fabrication method of homogeneous ([Sm.sub.0.5] [Y.sub.0.5]) [Ba.sub.2] [Cu.sub.3] [O.sub.7-[Delta]] superconductor substituted Y with Sm has been developed using zone melting process. A sample prepared by this method showed well textured microstructure and [([Sm.sub.0.5] [Y.sub.0.5]).sub.2] BaCu[O.sub.5] particles were uniformly dispersed in large ([Sm.sub.0.5] [Y.sub.0.5]) [Ba.sub.2] [Cu.sub.3] [O.sub.7-[Delta]] grain. The sample showed a sharp superconducting transition at 90.3 K. The magnetization measurements of the ([Sm.sub.0.5] [Y.sub.0.5]) [Ba.sub.2] [Cu.sub.3] [O.sub.7-[Delta]] sample exhibited the enhanced flux pinning compared with [YBa.sub.2] [Cu.sub.3] [O.sub.7-[Delta]] samples without Sm. Critical current densities of ([Sm.sub.0.5] [Y.sub.0.5]) [Ba.sub.2] [Cu.sub.3] [O.sub.7-[Delta]] was 1.8 x [10.sup.4] A/[cm.sup.2] at 10 kOe and 77 K. Index Terms - Critical current density, flux pinning, superconductor, zone melting process.