Hysteresis Behavior of Capacitance-Voltage Curve in (Ba0.6Sr0.4)TiO3 Thick Films Caused by Strained Heterostructure

(Ba0.6Sr0.4)TiO3 (BST) films with 300-1700 nm thicknesses were deposited on SrTiO3 (STO), 0.5wt% Nb-doped STO and (La0.5Sr0.5)CoO3-coated STO substrates by pulsed laser deposition. X-ray diffraction analysis results indicate that the deposited BST thick films were epitaxially grown on the substrates and c-lattice parameter of BST was increased compared with that of the bulk material owing to stress in the film. The fabricated film capacitors showed a hysteresis curve in the capacitance-voltage curve at room temperature. Hysteresis width linearly increased with increasing BST c-lattice parameter. (C) 2009 The Japan Society of Applied Physics