Thermal stability of amorphous LaScO3 films on silicon

The thermal stability of amorphous LaScO3 thin films deposited by molecular-beam deposition directly on (001) Si was investigated by high-resolution transmission electron microscopy (HRTEM), transmission infrared absorption spectroscopy (IRAS), and x-ray diffraction (XRD). IRAS indicated that the as-deposited films contained < 0.1 A of SiO2 at the interface between LaScO3 and silicon. XRD studies showed that the films remained amorphous after annealing in N-2 at 700 degrees C, although HRTEM showed structural order on an similar to 1 nm length scale even in the as-deposited films. By 800 degrees C, the LaScO3 had started to crystallize and formed a similar to 5 nm thick Sc-deficient interlayer between it and silicon. (c) 2006 American Institute of Physics

First-principles calculation of the band offset at BaO/BaTiO3_3 and SrO/SrTiO3_3 interfaces

We report first-principles density-functional pseudopotential calculations on the atomic structures, electronic properties, and band offsets of BaO/BaTiO$_3$ and SrO/SrTiO$_3$ nanosized heterojunctions grown on top of a silicon substrate. The density of states at the junction does not reveal any electronic induced interface states. A dominant perovskite character is found at the interface layer. The tunability of the band offset with the strain conditions imposed by the substrate is studied. Using previously reported theoretical data available for Si/SrO, Si/BaO and BaTiO$_{3}$/SrRuO$_{3}$ interfaces we extrapolate a value for the band alignments along the whole gate stacks of technological interest: Si/SrO/SrTiO$_3$ and Si/BaO/BaTiO$_3$/SrRuO$_3$ heterostructures.Comment: 12 pages, 6 figures, submitted to Phys. Rev.

Gills Just Want to Have Fun: Can Fish Play Games, Just like Us?

It is common to observe play in dogs, cats, and birds, but have we been ignoring play in one of the most common house pets of all&hellip; fish? Aquarium fish are often used as meditative decoration in family households, but it could be that fish have similarly diverse behavioral repertoires as mammals and birds. To examine this theory, we conducted field tests at local pet stores where a range of aquarium fish species was tested for responsiveness to laser pointer stimuli. Out of 66 species of fish tested, over 80% showed a tendency to be interested in the moving laser spots, particularly red ones. Whether this behavior constitutes play is an active topic of investigation that we examine in this work

Design and optimization of high-power, high-frequency FET's using pseudomorphic layers.

Strain modifies the bandstructure of a semiconductor such as GaAs in such a way that the threshold energy for impact ionization is increased in the strained layer. This effect and its application to submicron gate FET's are studied theoretically and experimentally. In the theoretical study the effects of strain on a semiconductor's bandstructure are studied. The effect of the bandstructure changes on impact ionization threshold energies is then shown. These calculated threshold energies are used in a two dimensional solution to the moments of the Boltzmann transport equation which includes impact ionization. This model is used to calculate the breakdown voltage in FET's and study the effects of the strained layers on these breakdown voltages. The model shows that breakdown in AlGaAs/GaAs HEMT's is dominated by impact ionization generation in the AlGaAs region. The most effective use of the thin, high threshold pseudomorphic material is in place of the AlGaAs layer under the gate. In the In\sb{0.52}Al\sb{0.48}As/In\sb{0.53}Ga\sb{0.47}As system the model shows that device breakdown is dominated by generation in the In\sb{0.53}Ga\sb{0.47}As channel. The best use of the pseudo-morphic layer in this case is in place of the channel. The experimental study includes the development of a submicron gate FET fabrication sequence. This fabrication study emphasizes the optimization of ohmic contacts to provide low access resistance and still be compatible with the rest of the fabrication process. After the FET fabrication sequence is developed, it is used to fabricate strained layer devices in both the GaAs system and the InGaAs on InP system. The power and frequency performance of these devices is compared to the power and frequency performance of lattice matched samples of similar design. These studies show that the pseudomorphic layers can improve the breakdown voltage of GaAs FET's by 65% with a corresponding improvement in the rf power output of 62%. The breakdown voltage of InAlAs/InGaAs FET's has been improved by 47% with the strained layers. The strained layer devices show no degradation in frequency performance compared to similar lattice matched devices.Ph.D.Electrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/104292/1/9513347.pdfDescription of 9513347.pdf : Restricted to UM users only

Relaunching Brands in the Automobile Industry

Das Thema der Arbeit umfasst und untersucht die Möglichkeiten, Chancen, Risiken, die ein Markenrelaunch bietet. Primär befasst sich die Ausarbeitung mit dem Markenrelaunch in der Automobilbranche. Eingehende Betrachtung finden Strukturdaten, Problemstellun-gen und Trends der Automobilindustrie. Inhaltlich befasst sich das Praxisbeispiel mit dem Markenrelaunch der Modellreihe Mercedes A-Klasse. Es wird sowohl die Markenidentität als auch das Markenimage im Detail analysiert. Die strategischen Fragen und operativen Umsetzungen im Prozess der Markenkommunikation sind explizit verifiziert. Im Rahmen des Fallbeispiels sind die Ursachen, die zum Relaunch führten, herausgear-beitet. Eine Analyse der Markenidentität erfolgt. Die Implementierung von Kontroll- und Evaluationstechniken sind orientierungsweisende Faktoren. Es kristallisiert sich heraus, dass ein Relaunch, ohne exakte Analyse von Zielen, Zielgruppen, Markendefinition, Wertevermittlung und öffentliche Kommunikation nicht umzusetzen ist. Im Praxisbeispiel gelang die Neuauflage, unter Berücksichtigung der getroffenen Maßnahmen

Study of microstructure in SrTiO₃/Si by high-resolution transmission electron microscopy

©2002 Materials Research Society. The original publication is available at: http://www.mrs.org/DOI: 10.1557/JMR.2002.0030Microstructure in the SrTiO₃/Si system has been studied using high-resolution transmission electron microscopy and image simulations. SrTiO₃ grows heteroepitaxially on Si with the orientation relationship given by (001)STO//(001)Si and [100]STO//[110]Si. The lattice misfit between the SrTiO₃ thin films and the Si substrate is accommodated by the presence of interfacial dislocations at the Si substrate side. The interface most likely consists of Si bonded to O in SrTiO₃. The alternative presentation of Sr and Si atoms along the interface leads to the formation of 2× and 3× Sr configurations. Structural defects in the SrTiO₃ thin film mainly consist of tilted domains and dislocations

Gills Just Want to Have Fun: Can Fish Play Games, Just like Us?

Simple Summary A pending question in animal biology is whether fish are capable of complex behaviors, such as play. We investigated this by shining laser pointers of various colors into home fish tank aquariums. We tested 66 different species and found that over 80% of fish showed an inquisitive response to the moving light stimuli, with the greatest interest in red laser spots. We review the literature on fish play and discuss whether the fish responses we observed can be considered play. It is common to observe play in dogs, cats, and birds, but have we been ignoring play in one of the most common house pets of all horizontal ellipsis fish? Aquarium fish are often used as meditative decoration in family households, but it could be that fish have similarly diverse behavioral repertoires as mammals and birds. To examine this theory, we conducted field tests at local pet stores where a range of aquarium fish species was tested for responsiveness to laser pointer stimuli. Out of 66 species of fish tested, over 80% showed a tendency to be interested in the moving laser spots, particularly red ones. Whether this behavior constitutes play is an active topic of investigation that we examine in this work