Evaluation of process parameters and nanoparticle seeding of sol-gel derived lead-magnesium-niobium titanate thin films

A near morphotropic phase boundary lead-magnesium-niobium titanate material system was synthesised by the sol-gel method; its thin films were deposited with or without nanoparticle (np) seeding and processed by the rapid thermal annealing. Influences of some process parameters and the np seeding on various properties of the resultant films were systematically investigated. Although no reduction in annealing temperature was achieved upon np seeding, the results indicated that nps might indeed play a role as nucleation centres during the crystallisation. All in all, the lead-magnesium-niobium titanate thin film system described here (particularly those annealed at higher temperatures) appeared to be suitable for its potential applications in wireless communication systems as ultrahigh dielectric constant ε value capacitors; the unexposed film annealed at 750°C, for instance, exhibited the highest dielectric constant ε (1425) with a low loss (loss tangent, ~0·04) along with a strongly pronounced perovskite phase (96·5%).