Dielectric properties of artificially textured (Ba0.5Sr0.5)TiO3 thin film prepared by pulsed laser deposition

Metal-ferroelectric-metal (MFM)-structured (Ba0.5Sr0.5)TiO3 (BST) thin films were deposited on a Pt(111)/TiO2/SiO2/Si substrate by pulsed laser deposition. The textures of BST films, such as those with (111), (100), and (110) orientations, were successfully controlled by oxygen partial pressure and laser energy under deposition. In spite of the use of (III)-oriented platinized silicon substrates, highly (100)-textured BST film was formed by control of the oxygen flow rate. Voltagedependent dielectric properties, including dielectric constant (epsilon(r)) and dielectric loss (tan delta) of the BST capacitors, were studied by capacitance-voltage (C - V) measurements at room temperature. Tunability and figure of merit related to the texture ratio of BST (100) in BST films are also discussed. The texture-control method of MFM-structured BST film using the pulsed laser deposition technique indicated that such film could be a potential candidate for frequency agile device applications.