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CONDUCTIVE ALUMINUM COMING SOON Researchers at Pacific Northwest National Laboratory (PNNL), Richland, Wash., are working on ways to increase the conductivity of aluminum and make it economically competitive with copper. [...]

In recent years a very large amount of data has been collected regarding devices formed by multiwalled carbon nanotubes (MWCNTs) in polymer matrix as well as single nanotubes. Conversely, very little investigation exists of nanotube networks composed of a small number of MWCNTs. A detailed investigation of the long time stability, adhesion to the surface, and topological structure of the interconnections between MWCNTs is reported here. Three different microscopy techniques, focused ion beam (FIB), scanning electron microscope (SEM), and atomic force microscope (AFM), were used to investigate the interconnection of MWCNTs deposited by electrophoresis on a thermally oxidized silicon wafer with aluminum microgap structures. SEM, AFM, and FIB imaging revealed an interesting interconnection morphology between the drop casted MWCNTs. In particular it was found that in some cases the MWCNTs were connected to each other in a geometry similar to a twisted structure. Furthermore a good stability of the sample in time has been found, proving a strong adhesion of the nanotubes to the oxide surface. Despite the fact that electrical contacts with aluminum to carbon nanotube--based devices are in general not very reliable, using the dielectrophoresis deposition technique with an adequate subsequent annealing procedure, long-term stable temperature sensors with carbon nanotube networks in the aluminum contact microgap were realized. Their temperature dependence can be explained by modeling the internanotube contact resistance. PACS Nos.: 73.63.Fg, 85.35.Kt, 68.37.Hk. Dans les dernieres annees, beaucoup de donnees ont ete accumulees concernant des dispositifs formes de nanotubes de carbone multicouches (MWCNT) dans des matrices de polymeres ou comme simples nanotubes. A contrario, peu est connu des reseaux de nanotubes constitues par un petit nombre de MWCNTs. Nous presentons ici une etude poussee de la stabilite a long terme, de l'adhesion a la surface et de la structure topologique des interconnexions entre les nanotubes multicouches. Trois differentes techniques microscopiques, le faisceau ionique focalise (FIB), le microscope electronique a balayage (SEM) et le microscope a force atomique (AFM), sont utilisees pour analyser les interconnexions de MWCNTs deposes par electrophorese sur la surface thermiquement oxydee d'un wafer de silicium avec des contacts micro-separes d'aluminium. Les techniques d'imagerie SEM, AFM et FIB revelent une interessante morphologie d'interconnexions entre les MWCNTs obtenus par drop casting. Dans certains cas particuliers, nous trouvons que les MWCNTs sont connectes les uns aux autres dans une geometrie similaire a une structure vrillee. Nous observons que l'echantillon a une bonne stabilite temporelle, ce qui prouve une forte adhesion entre les nanotubes et la surface d'oxyde. Malgre le fait que les contacts electriques d'aluminium avec des dispositifs bases sur les nanotubes de carbone sont en general peu fiables, l'utilisation d'une technique de depot bi-electrophorese avec une procedure adequate de recuits subsequents, permet d'obtenir une stabilite a long terme en temperature pour des senseurs faits de reseaux de nanotubes avec contact en aluminium micro-separes. [Traduit par la Redaction], 1. Introduction Carbon nanotube networks (CNNs) are very attractive for electronic and optoelectronic device applications. Besides single-walled carbon nanotube--based CNNs, that are, for example, used for the realization of thin [...]

An electric current, applied during deformation, has been shown to reduce the deformation force/energy, while also increasing the maximum achievable strain and decreasing springback. Considering this, the present work initiates the development of a finite element model to investigate electricity's thermal/structural effects on a tensile specimen. The model allows the effect of joule-heating to be separated from other nonthermal property changes caused by the electricity. Comparison with experimental tensile testing with respect to the predicted stress-strain behavior and transient temperature profiles demonstrates the model predicts these behaviors adequately. A multifield large deformation finite element model is then developed. The model evaluates the stress-strain characteristics of the material while the specimen is carrying a large dc current and is being deformed, incorporating the effect of thermal softening. The simulation results are compared with surface infrared temperature measurements in order to verify the finite element model and then to actual deformation results in order to attain more qualitative and quantitative insight into the effects of the electric field. [DOI: 10.1115/1.4000310]

Spatial and spectral information are combined and it is shown that single filaments in broad ridge (Al,In)GaN laser diodes (LDs) are phase-locked and form supermodes. Stable in-phase coupling of the single emitters or filaments over a wide current range is achieved in order to produce a stable laser beam for high power applications.

A study was conducted to examine the electrical and optical property modifications in presence of a floating nanometric metallic layer at the interface between two organic light-emitting diodes (OLEDs) in a stacked structure. Findings highlight that the presence of thin aluminum layer could cause the switching behavior, probably introducing a charge trapping interface.

Several theoretical analyses are conducted to explain the design and working of the high-Q, quartz thin film resonators that work at a frequency of 3.4GHz. The resonators are shown to exhibit excellent frequency-temperature behavior and hence are widely used in various different high-frequency timing devices.

Several experimental and computational studies are conducted to determine the forward current density ([J.sub.F])-forward voltage ([V.sub.F]) characteristics of 4H-silicon junction barrier Schottky (JBS) diodes. These characteristics are shown to be highly affected by the lateral spreading of the implanted aluminum ions and implantation-induced defects.