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The electrical properties of the fresnoite BaO–TiO2–SiO2 system were studied over a range of amorphous and crystalline microstructures using as-quenched glass (BTS-gl), partially crystallized glass (BTS-pc, heat treated at 740°C for 100 min) and fully crystallized glass ceramic (BTS-gc, heat treated at 750°C for 180 min). Combination of impedance and moduli plots along with equivalent circuit models were utilized in an attempt to understand the contributions arising from different regions in the glass ceramic, i.e. the glassy matrix, crystalline phase, and crystal–glass interface region. Electrical conductivity of the samples exhibited frequency dispersions at different temperatures suggesting localized motion of ions. The activation energies calculated from dc resistivity–temperature plots (Edc) and relaxation frequency–temperature plots (Ef) seem to increase as the degree of crystallinity increases suggesting that ionic transport becomes more difficult in crystallized glasses.

The use of PZT films in sliver-mode high-frequency ultrasonic transducers applications requires thick, dense, and crack-free films with excellent piezoelectric and dielectric properties. In this work, PZT composite solutions were used to deposit PZT films >10 μm in thickness. It was found that the functional properties depend strongly on the mass ratio of PZT sol-gel solution to PZT powder in the composite solution. Both the remanent polarization, P(r), and transverse piezoelectric coefficient, e(31,) (f), increase with increasing proportion of the sol-gel solution in the precursor. Films prepared using a solution-to-powder mass ratio of 0.5 have a remanent polarization of 8 μC/cm(2), a dielectric constant of 450 (at 1 kHz), and e(31,) (f) = -2.8 C/m(2). Increasing the solution-to-powder mass ratio to 6, the films were found to have remanent polarizations as large as 37 μC/cm(2), a dielectric constant of 1250 (at 1 kHz) and e(31,) (f) = -5.8 C/m(2).

A KrF pulsed excimer laser (248 nm) was utilized to crystallize sputtered La-modified Pb(Zr,Ti)O3 (3:30:70) (PLZT) films on LaNiO3-coated silicon substrates. The film surface was irradiated with defocused laser pulses in an oxygen ambient at various substrate temperatures. Polycrystalline, phase pure perovskite PLZT thin films were produced for substrate temperatures of 250°C and higher. The dielectric constant and loss tangent values of laser-assisted crystallized (10 min exposure at 10 Hz using a substrate temperature of 400°C) PLZT thin films at 10 kHz were 406 and 0.027; in comparison, rapid thermal annealed films (annealed at 700°C for 1 min) showed values of 400 and 0.021, respectively. Laser crystallized films exhibited a remanent polarization value of 14 μC/cm2 with a coercive field |(E+c+E−c)|/2 of 95 kV/cm.