Low-Temperature Processing of Highly Oriented Pb(ZrXTi1-X)O3 Thin Film with Multi-Seeding Layers

An improved sol-gel process using molecular-designed alkoxide precursor was described for a lead zirconate titanate (PZT) thin film. This method involves the insertion of inter-layer films of a perovskite lead titanate (PT) layer as a transient seeding layer between each PZT layers, which offers nucleation sites to reduce the activation energy for the crystallization, leading to the low processing temperature (hereafter, abbreviated as a multi-seeding process). An intermediate pyrochlore phase developed in the film by annealing at around 400° C in an air, and then was completely converted to a perovskite phase at a low temperature of 450° C. The relative permittivity of the resulting film annealed at 450° C increased with increasing film thickness and reached about 350 at 1.9 µ m. In addition, highly oriented PZT film was obtained by annealing at 500° C for 2 hours in an air. This highly oriented film exhibited high relative permittivity of about 500 due to its microstructure. As a result, it was demonstrated that multi-seeding process was desirable for obtaining a single phase perovskite PZT film at low temperatures.