Superconducting Tl-Ca-Ba-Cu-oxide films have been prepared on yttria stabilized zirconia substrates via the reaction of T1 2 O vapor with precursor Ca-Ba-Cu-oxide films prepared by the spray pyrolysis of a solution of the metal nitrates. The vapor reaction process, evaluated in both air and oxygen ambients, was carried out in a two-zone reactor which permitted the independent control of the temperatures of the sample and of a boat containing thallium oxide. Sample temperatures of 865-905 °C and boat temperatures of 775-870 °C were investigated. X-ray diffraction analysis of the best samples, which were prepared in an oxygen ambient at sample temperatures of 895-900 °C and boat temperatures of 805-810 °C, revealed the presence of a highly oriented Tl 2 Ca2Ba 2 Cu3O 10+) , phase with a trace of the Tl 2 CaBa 2 Cu 2 0 8+r phase. FWHM's of ~ 2° 9 were obtained in x-ray rocking curve analyses of the oriented 2223 phase. T c (0) values of 95-105 K were measured for the better samples, and a zero field critical current density of 28 800 amps/cm 2 was measured at 77 K for the best sample. SEM micrographs taken of the highest J c samples reveal a highly textured structure consisting of platelike crystals.

Aluminum corrosion in a polymer-coated circuit model was studied using in-situ microscopy coupled with time-lapse video recording.Pinholes in the polymer coating and exposure to water with bias voltage of 40V applied between adjacent aluminum tracks resulted in fast anode corrosion, accompanied by gas evolution. A mathematical model is developed that is in good agreement with the observed current-time relationship. The rate of corrosion is controlled by the resistance of a 6000A thick water film occupying the space of the corroded Al film between wafer and polymer coating.A tentative corrosion mechanism is proposed.

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