Fabrication and dielectric properties of barium strontium titanate nano-particles/amorphous lead zirconate titanate composite thin film

A low temperature synthetic method, which combines metal-organic decomposition and a nm-seeding technique, was applied to the fabrication of barium strontium titanate (BST) nano-particle/amorphous lead zirconate titanate (PZT) composite thin films. A metal-organic solution of PZT was mixed with a suspension of BST nano-crystalline particles to prepare a precursor solution. The mixed solution was spin-coated on a Pt/Ti/SiO₂/Si substrate and annealed at various temperatures to prepare composite thin films with a thickness around 300 nm. Organic components in the films decomposed at 350 °C, and the composite film of PZT amorphous and BST nano-crystalline particles could be prepared at this temperature. The film had smooth surface with a root mean square roughness less than 20 nm. The dielectric constant and dissipation factor of the composite thin films at 10 kHz obtained 70 and 0.036, respectively.