The Influence of Ink Chemistry on the Microstructure Evolution and GHz RF Response of Printed Ag Transmission Lines.

High-frequency transmission is limited to the skin depth in metals. Because poor conductivity cannot be compensated for by increasing the conductor thickness as with DC, optimal transport properties are prerequisites for radio frequency (RF) use. Structural and chemical analyses of transmission lines printed using a traditional ink consisting of Ag nanoflakes in a dispersing phase revealed that optimized thermal treatments yielded thorough burnout of the binder, significant grain growth, elimination of the pore volume, and electrical responses that were comparable to values obtained for thermally evaporated, fully dense Ag controls.

Synthesis, spectroscopic properties, and photoconductivity of black absorbers consisting of pt(bipyridine)(dithiolate) charge transfer complexes in the presence and absence of nitrofluorenone acceptors.

The diimine-dithiolato ambipolar complexes Pt(dbbpy)(tdt) and Pt(dmecb)(bdt) (dbbpy = 4,4'-di-tert-butyl-2,2'-bipyridine; tdt(2-) = 3,4-toluenedithiolate; dmecb = 4,4'-dimethoxyester-2,2'-bipyridine; bdt(2-) = benzene-1,2-dithiolate) are prepared herein. Pt(dmecb)(bdt) exhibits photoconductivity that remains constant (photocurrent density of 1.6 mA/cm(2) from a 20 nm thin film) across the entire visible region of the solar spectrum in a Schottky diode device structure.

Microstructure and electronic band structure of pulsed laser deposited iron fluoride thin film for battery electrodes.

Battery electrodes in thin-film form are free of the binders used with traditional powder electrodes and present an ideal platform to obtain basic insight to the evolution of the electrode-electrolyte interface passivation layer, the formation of secondary phases, and the structural underpinnings of reversibility. This is particularly relevant to the not yet fully understood conversion electrode materials, which possess enormous potential for providing transformative capacity improvements in next-generation lithium-ion batteries. However, this necessitates an understanding of the electronic charge transport properties and band structure of the thin films.

The influence of high dielectric constant aluminum oxide sputter deposition on the structure and properties of multilayer epitaxial graphene.

High dielectric constant aluminum oxide (Al(2)O(3)) is frequently used as the gate oxide in high electron mobility transistors and the impact of its deposition by radio frequency (RF) magnetron sputtering on the structural and electrical properties of multilayer epitaxial graphene (MLG) grown by graphitization of silicon carbide (SiC) is reported. Micro-Raman spectroscopy and temperature dependent Hall mobility measurements reveal that the processing induced changes to the structural and electrical properties of the MLG can be minimal when the oxide deposition conditions are optimal. High-resolution transmission electron microscopy (HRTEM) analysis confirms that the Al(2)O(3)/MLG interface is relatively sharp and that our thickness approximation of the MLG using angle resolved x-ray photoelectron spectroscopy (ARXPS) is accurate.

Structural and electrical characterization of ohmic contacts to graphitized silicon carbide.

Titanium was deposited onto silicon carbide (6H-SiC) using the 248 nm line of an excimer laser in a vacuum of 10(-6) Torr, and ohmic contacts were formed by annealing the structure at approximately 1000 degrees C. Further anneals between 1350 and 1430 degrees C did not degrade the formed contacts, and Raman analysis confirmed that sublimation of silicon from the near surface layers of the silicon carbide between the contact pads resulted in graphene formation after 5 min, 1428 degrees C anneals. The graphene formation was accompanied by a significant enhancement of ohmic behavior, and, it was found to be sensitive to the temperature ramp-up rate and annealing time.