Structure of Ba0.7Sr0.3TiO3 Films Grown by Chemical Solution Deposition on Polycor Substrates

The structure of barium strontium titanate (BST) films grown by chemical solution deposition on polycor substrates was studied by transmission electron microscopy, high-resolution microscopy, and x-ray diffraction analysis. It was found that a grain structure inhomogeneous in cross section is formed after two-step crystallization at T = 700 and 950 degrees C. There are equiaxed grains (44.2 nm in average size) in the BST-polycor interfacial region and a multilevel columnar structure (grain height up to 150 nm) with {100} texture in the film bulk. Grain growth inhibition during high-temperature annealing and underlayer formation in the interfacial region are caused by a change in the substrate structure, i.e., grain reorientation and {112} texture formation.