Thickness dependence of dielectric constant in barium strontium titanate thin films

Radio frequency magnetron sputtered Ba0.8Sr0.2TiO3 thin films have been dep osited on silicon Si/SiO2/Ti/TiN/Pt substrate. The structural and electrica l properties have been investigated using X-ray diffraction and capacitance -voltage characteristics of fabricated capacitors. The growth and orientati on of the film have been found to depend upon the type of substrates and de position temperatures. The effective dielectric constant of BST film in Si/ SiO2/Ti/TiN/Pt/BST/Al thin film capacitor is found to increase with the inc reasing thickness of the film. A space charge layer with low dielectric con stant is found to form at the film electrode interface.