Preparation of nano-structured BaTiO3 thin film by electrophoretic deposition and its characterization

Nano-structured BaTiO3 (BTO) thin films were electrophoretically deposited from BTO nanoparticle suspensions. The microstructural properties of the nanoparticles and thin films were examined through XRD, HR-TEM, and SEM techniques. BTO nanocrystallites in a pseudo-cubic perovskite phase with an average particle size of about 10 nm were synthesized by a high-concentration sol-gel process. By dispersing a piece of BTO bulk gel into a mixed solvent of 2-methoxyethonal and acetylacetone, the well-dispersed and stable suspensions of BTO nanocrystallites were obtained. From these suspensions, crack-free nano-structured BTO thin films with different thickness from 100 nm to several micrometers were deposited on Pt/Ti/SiO2/Si substrates by electrophoretic deposition (EPD). The prepared films exhibited a uniform nanostructure, and a smooth surface with a roughness under 10 nm. The microstructural and dielectric properties of sintered BTO thin films were evaluated.