Conducting films properties

Kinetic stability of lithium and the lithiated carbons results from film formation which yields protective layers on lithium or on the surfaces of carbonaceous materials, able to conduct lithium ions and to prevent the electrolyte from continuously being reduced film formation at the Li/PC interphase by the reductive decomposition of PC or EC/DMC yielding alkyl-carbonates passivates lithium, in contrast to the situation with DEC where lithium is dissolved to form lithium ethylcarbonate [149]. EMC is superior to DMC as a single solvent, due to better surface film properties at the carbon electrode [151]. However, the quality of films can be increased further by using the mixed solvent EMC/EC, in contrast to the recently proposed solvent methyl propyl carbonate (MPC) which may be used as a single sol-... 

Polyimides Powder, solutions Excellent high temperature properties, 400 to about 700 F. Difficult to process. High-temperature cable shielding, conductive film. 

Most polymers are very good electrical insulating materials because of their chemical composition, i.e., their electrical conductivity is exceptionally low. Because of this important property, many plastics are used to produce electrically nonconductive parts. However, the high surface resistance leads to an unwanted property the material is prone to electrostatic charge accumulation. To facilitate dissipation of the charge, antistatic agents are incorporated, which combine with atmospheric moisture on the plastic surface to form a conductive film. 

TCNQ-Polyphosphazene Systems. Tetracyanoquinodimethane (XX) salts crystallize in the form of stacked arrays that allow electrical semiconductivity (42). Although this phenomenon has been studied in many laboratories, it has not been possible to fabricate conductive films or wires from these substances because of the brittleness that is characteristic of organic single crystals. However, it seemed possible that, if the flexibility and ease of fabrication of many polyphosphazenes could be combined with the electrical properties of TCNQ, conducting polymers might be accessible. 

Ellipsometiy is unrivaled for the measurement of the properties of thin films, particularly those on electrodes in solution. It has extraordinary sensitivity and can measure films from submonolayers up to films having a thickness near to that of the wavelength of the light incident upon the electrode surface. Moreover, ellipsometiy gives not only the thickness of the film but also its refractive index and, in the case of conducting films, the absorption coefficient. 

The obtaining of tin(IV) alkoxides was first reported in a well-known publication by Meerwein and Bersin [1101] devoted to bimetallic alkoxides. At the end of the 1950s Bradley [222] and Make [1049] practically simultaneously devoted the synthetic approaches to and described the properties of nearly all major representatives of the Sn(OR)4homologous series. During the last 10 to 20 years interest in these compounds was renewed due to the prospect of their application in the synthesis of optically transparent and conducting films based on Sn02, and also of related ceramic materials. The alkoxides of Sn(IV) were considered in detail in a review by Hampden-Smith etal. [702],... 

Comparable to thiophene, pyrrole is a five-membered heterocycle, yet the ring nitrogen results in a molecule with distinctly different behavior and a far greater tendency to polymerize oxidatively. The first report of the synthesis of polypyrrole (PPy) 62 that alluded to its electrically conductive nature was published in 1968 [263]. This early material was obtained via electrochemical polymerization and was carried out in 0.1 N sulfuric acid to produce a black film. Since then, a number of improvements, which have resulted from in-depth solvent and electrolyte studies, have made the electrochemical synthesis of PPy the most widely employed method [264-266]. The properties of electrosynthesized PPy are quite sensitive to the electrochemical environment in which it is obtained. The use of various electrolytes yield materials with pronounced differences in conductivity, film morphology, and overall performance [267-270]. Furthermore, the water solubility of pyrrole allows aqueous electrochemistry [271], which is of prime importance for biological applications [272]. 

To fabricate the integrated circuit (IC), layers with various electrical properties must be introduced into or deposited onto the substrate. These layers may consist of insulating, semiconducting, and conducting films. The construction of the layers in only the desired areas relies on a series of patterning steps which is briefly illustrated in Figure 1. Light sensitive... 

Film growth is under oxygen-rich conditions so the films are stoichiometric. The high partial pressure of the reactive gas limits the surface mobility, so film properties are not ideal. Furthermore, dopants are oxidized and thus, TCO films become non-conductive. 

Properties such as high density and homogenous conductivity define the quality of ceramic targets. Ceramics with nonconductive inclusions exhibit arcing and nodule growth on the target surface, while targets with low density exhibit inferior film properties due to contaminations with different species. 

S. Holdkroft and B. L. Funt, Preparation and electrocatalytic properties of conducting films of polypyrrole containing platinum miroparticulates, J. Electroanal. Chem. 240, 89-103 (1998). 

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