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Deviations from stoichiometry occurring during the crystal growth of lithium niobate have been studied by 93Nb NMR and by shifts in the ferroelectric transition temperature. The high-temperature phase equilibria of nonstoichiometric lithium niobate were accurately determined by these techniques together with DTA and crystal-growth experiments. The congruently melting composition is located at 48.6 mole% Li2O and the solid-solution region at room temperature extends from 48% to 50% Li2O. The implications of growth at noncongruently melting compositions on the compositional uniformity of lithium niobate are discussed in detail.

Deposition of nickel silicide nanowires has been achieved in the temperature range of 320 to 420°C by decomposition of silane on nickel surfaces. The substrates consisted of Ni foils and thin Ni films (ϳ10-100 nm) evaporated on 1-m-thick layers of SiO 2 predeposited on Si wafers. Nanowire growth between two metal pads was achieved with aid of an electric field. It was found that thinner diameter nanowires were produced at low temperatures and that the density of the nanowires was dependent on the reactor pressure. The current-voltage relationship of these nanowires has also been examined.

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