Preparation of Pb(Zr_0.53Ti_0.47)O₃ Thick Films by an Interfacial Polymerization Method on Silicon Substrates and Their Electric and Piezoelectric Properties

Abstract

Pb(Zr 0.53 Ti 0.47 )O 3 (PZT) films of 10 to 50 µm in thickness were prepared by a new sol-gel process using an interfacial polymerization technique. The interfacial polymerization process is that an alkoxide precursor solution is poured on the surface of water in a container to form a gel film at the interface between the two immiscible liquids. The precursor solution was prepared by adding PZT alkoxide solution, PZT powders coated with Pb 5 Ge 3 O 11 (PG), and a surfactant into hexane solvent. After the polymerization at the interface, the gel films were gently placed on a silicon substrate by draining the water in the container. The gel films containing PZT powders were sintered at 950°C for 10 min to obtain crystallized PZT films. The remanent polarization of a PZT thick film was 33.1 µC/cm 2 . The piezoelectric d 33 constant measured with a Mach-Zehnder interferometer was 225 pm/V and was independent of frequency from 0.2 to 3 kHz. A process to create patterns of PZT thick films was developed. The resonance frequencies of four square patterns of 2×2 mm 2 in size were consistent, which indicated that the interfacial polymerization process enables the fabrication of uniform thick films in a large area.