Structural, microstructural, optical and dielectric properties of Ba0.75Sr0 25TiO3 thin films deposited by sol-gel

The effects of annealing on the structure, microstructure, stoichiometry, optical and dielectric properties of Ba0.75Sr0.25TiO3 thin films have been studied. The films are grown on Pt(111)/TiO2/SiO2/Si(100) and auartz substrates by sol-gel. X-Ray diffraction measurements showed that the films annealed at temperatures of 500-675°C for 2h are polycrystalline. A significant change in the interfacial composition for thin films annealed at 825°C is observed. A relatively sharp tail of the transmission spectra for films annealed at temperature in the range 500-675°C indicates a narrow distribution of grain size for these films. Annealing films caused the dielectric constant to become more like the bulk.