We have characterized the phase behavior of mixtures of the cationic surfactant cetyltrimethylammonium bromide (CTAB) and the organic salt 3-sodium-2-hydroxy naphthoate (SHN) over a wide range of surfactant concentrations using polarizing optical microscopy and X-ray diffraction. A variety of liquid crystalline phases, such as hexagonal, lamellar with and without curvature defects, and nematic, are observed in these mixtures. At high temperatures the curvature defects in the lamellar phase are annealed gradually on decreasing the water content. However, at lower temperatures these two lamellar structures are separated by an intermediate phase, where the bilayer defects appear to order into a lattice. The ternary phase diagram shows a high degree of symmetry about the line corresponding to equimolar CTAB/SHN composition, as in the case of mixtures of cationic and anionic surfactants.

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Experiments show that pure copper films can be formed at temperatures below 190 °C by H2 plasma assisted chemically vapor deposited copper(II)-hexafluoroacetylacetonate. A fundamental surface reaction mechanism has been derived for the reaction between dissociatively adsorbed precursor and atomic hydrogen produced in the plasma. The mechanism suggests that the deposition rate is proportional to [Cu(HFA),] 1/2 [H] and film purity improves with an increase in atomic hydrogen concentration. A new lumped parameter model has also been developed that agrees very well with experiments, to relate the operating conditions to the concentrations of Cu(HFA)2 and atomic hydrogen. Our model shows that at temperatures above 200 °C, surface recombination of atomic hydrogen decreases adsorbed [H] leading to copper films possessing high resistivity. It also indicates that at plasma powers above 60 W, high electron concentrations lead to the gasphase decomposition of the precursor and high film resistivity. An apparent activation energy of 5.0 kcal/mol is also suggested for the deposition, by the experiments and the reactor model.