BaxSr1−xTiO3 thin films by a chemical process

Stoichiometric BaxSr1-xTiO3 samples with various of x were prepared by a solution method. The starting materials were titanium isopropoxide and hydroxides of barium and strontium. Powders were obtained by evaporation of the precursor solution, and thin films were deposited by spin coating. The annealing temperature required to obtain complete conversion to the crystalline material increases with increasing x and ranges from 150 to 600 °C. High quality polycrystalline films of Ba0.5Sr0.5TiO3 were achieved on a silicon substrate at 550 °C. Leakage current as a function of applied voltage (I–V) measurements on the metal-insulator-semiconductor structure (where the insulating layer is Ba0.5Sr0.5TiO3 film) on n-type silicon substrates showed diode-like behavior.