Lead zirconate titanate (PZT) films were deposited on platinized silicon substrates by spin coating using PZT sols containing polyvinylpyrrolidone (PVP) as an additive. Single-layered 1-μm-thick PZT films with 60∕40 composition were fabricated using two successive spin coatings followed by a single heat treatment step. The crack formation was effectively suppressed by the presence of nanosized pores which were generated during the heat treatment. The film has a preferred orientation corresponding to the (100) crystallographic direction. The ferroelectric and piezoelectric properties of the specimen were comparable to those of a film with same composition and thickness but prepared by the conventional sol-gel procedure.

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A method to simultaneously measure the longitudinal (d33) and transverse (d31) piezoelectric coefficients of a lead zirconate titanate (PZT) thin film was developed. This system was based on the pneumatic loading method but was modified to monitor the radial strain when a pressurized gas was introduced into the chamber. The results of the bulk piezoelectric material measured by this system coincided with that measured by both the Berlincourt method and the resonance method. The effective d33 and the real d31 of the PZT thin film fabricated by the sol-gel multiple coating method, and poled at 300 kV/cm were 125 and −60 pC/N, respectively. The real d33 estimated upon considering the constraints by the silicon substrate was 180 pC/N.

The sintering behavior and piezoelectric properties of the lead zirconate titanate (Pb(ZrTi)O3, PZT)–lead zinc niobate (Pb(Zn1/3Nb2/3)O3, PZN) system were investigated. The sintering temperature required for full densification of the PZT‐PZN system was significantly lowered when the proportion of PZN was increased. The density of the specimen composed of 60% PZT and 40% PZN (0.6PZT‐0.4PZN, Pb((Zr0.47Ti0.53)0.6–(Zn1/3Nb2/3)0.4)O3) sintered at 880°C for 4 h was 8.15 g/cm3, which was >97% of the theoretical value. This improved densification behavior was attributed to the combined effects of the high sinterability of PZN and the stability of the PZT pcrovskite structure. The piezoelectric and dielectric properties of the 0.6PZT‐0.4PZN specimen sintered at 880°C were comparable with those of a specimen with the same composition sintered at 1200°C for 2 h. The piezoelectric coefficient (d33) and the electromechanical coupling factor (kp) of the 0.6PZT‐0.4PZN specimen sintered at 880°C were 460 pC/N and 0.6, respectively.

This study examined the effects of permanent residual compressive stress on the ferroelectric properties of PbZrxTi1−xO3 (PZT) films that was induced during cooling after annealing. PZT films were deposited on the tensile side of elastically bent silicon substrates by rf magnetron sputtering using a single oxide target. Compressive stress was induced on the film by removing the substrate from the holder immediately after annealing. The compressive stress effectively compensated for the inherent tensile stress that had developed during cooling. The ferroelectric properties were enhanced markedly by the induced stress; the remnant polarization and the saturation polarization increased by 35% and 24%, respectively, while the coercive field did not change much. Contrary to the ferroelectric properties, the dielectric properties decreased slightly by the stress.