Effect of yttrium doping on the dielectric properties of CaCu3Ti4O12 thin film produced by chemical solution deposition

Pure and yttrium substituted CaCu₃Ti_4 − xY_xO_{12 − x / 2} (x = 0, 0.02, 0.1) thin films were prepared on boron doped silica substrate employing chemical solution deposition, spin coating and rapid thermal annealing. The phase and microstructure of the sintered films were examined using X-ray diffraction and scanning electron microscopy. Dielectric properties of the films were measured at room temperature using electrochemical impedance spectroscopy. Highly ordered polycrystalline CCTO thin film with bimodal grain size distribution was achieved at a sintering temperature of 800 °C. Yttrium doping was found to have beneficial effects on the dielectric properties of CCTO thin film. Dielectric parameters obtained for a CaCu₃Ti_4 − xY_xO_{12 − x / 2} (x = 0.02) film at 1 KHz were k ∼ 2700 and tan δ ∼ 0.07.