Effects of individual layer thickness on the structure and electrical properties of sol-gel-derived Ba0.8Sr0.2TiO3 thin films

Ba0.8Sr0.2TiO3 thin films were prepared with various individual layer thick nesses using a sol-gel process, The individual layer thickness strongly aff ected the structure, ferroelectricity, and dielectric properties of the fil ms, The films prepared with an individual layer thickness of 60 nm showed s mall equiaxed grains, cubic structure, temperature-independent dielectric c onstant, and no ferroelectricity, The films prepared with an individual lay er thickness of 8 nm showed columnar grains, tetragonal structure, good fer roelectricity, and two dielectric peaks in the dielectric constant-temperat ure curve. The individual layer thickness for layer-by-layer homoepitaxy gr owth that resulted in columnar grains was <20 nm.