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Physical and chemical properties of plasma-polymerized SiOCH films were investigated using ring-type siloxane monomers with several kinds of side-chain chemicals, and a design principle of the material and plasma-process was derived to obtain a porous SiOCH film of k < 2.5 with sub-nanometer-scaled porous structure framed by the original ring siloxane backbone. Here, the backbone siloxane structure is fixed as a six-membered Si-O ring of the 0.35 nmΦ, and no progen gas and no post-cure-process were utilized. It was found that unsaturated hydrocarbon side chains such as vinyl increase the deposition rate, and the original monomer structure tends to be kept, reducing the dielectric constant with the porous structure. Large alkyl groups increase the hydrocarbon content in the film as well as the deposition rate. The low radio-frequency power plasma with high precursor concentration also helps the original chemical structure to be preserved. The best solution is to use the ring-type siloxane with both of the vinyl (unsaturated hydrocarbon) and the large alkyl (saturated hydrocarbon) under the low-power plasma condition with the high partial pressure of the precursor. The plasma-polymerized porous SiOCH film is a strong candidate for the low-k film in scale-down 45/32 nm node ultralarge-scaled integrated interconnects featured by the simple and low-cost fabrication processes. [ABSTRACT FROM AUTHOR]

A rigorous physics-based mathematical model for a solid oxide iron-air redox flow battery system is presented in this paper. The modeled flow battery system combines a Fe-FeO redox couple as the energy storage unit and a regenerative solid oxide fuel cell as the electrical functioning unit in a 2D axial symmetric geometry. This model was developed from fundamental theories of reaction engineering in which basic transport phenomena and chemical/electrochemical kinetics are included. The model shows good agreement with the experimental data. Simulation results for the chemical, electrochemical and transport behavior of the battery are discussed. [ABSTRACT FROM AUTHOR]

Scanning Kelvin probe (SKP) potentiometry was used to systematically investigate the effect of surface abrasion and subsequent heat-treatment on the open-circuit potential (OCP) of AA6016 in humid air. SKP is also used to follow the kinetics of filiform corrosion (FFC) and to determine characteristic potentials associated with the electrolyte-filled filiform head and dry filiform tail. It is shown that simply abrading with 180 grit SiC paper produces a surface potential ca. 0.2 V lower than the bulk. When the abraded sample was overcoated with a 30 μm layer of PVB (polyvinyl butyral) and exposed to HCI a fast, superficial filiform corrosion was observed in which metal loss was limited to the thickness of the surface layer (i.e., ca. 1 μm). Filiform head OCP values were similar to those of the surface layer, whereas filiform tail OCP values were similar to the bulk. A mechanism is proposed in which the ultrafine grain structure of the surface layer produces an anodic activation, and the potential difference between the surface layer and the bulk provides an increased thermodynamic driving force for corrosion. For postabrasion heat-treatment temperatures between 180 and 350°C the fast filiform process was followed by a slower, deeper form of FFC. [ABSTRACT FROM AUTHOR]