Postdeposition annealing effect on ( Ba 0.6 , Sr 0.4 ) TiO 3 thick films deposited by aerosol deposition method

The effect of thermal treatment on physical properties of ( Ba 0.6 , Sr 0.4 ) TiO 3 (BST60) ferroelectric thick films deposited by aerosol deposition (AD) technique has been investigated by x-ray photoelectron spectroscopy (XPS) and complex impedance spectroscopy (CIS) to explain the leakage current behavior of the films. The leakage current increases when the thermal treatment temperature was increased. By XPS analysis it was found that the films are not formed entirely of BST60 phase. Carbonates of Ba or/and Sr and TiO 2 coexist with the BST phase, and it is believed to play an important role in the properties of the AD-deposited BST60 thick films. CIS analysis revealed that the grain boundary region becomes less resistive with the increase in thermal treatment temperature. Also, it has been observed after comparing the electric modulus of green and thermally treated samples that the activation energy for electron-hole formation becomes smaller with the increase in thermal treatment temperature above 600 ° C . Decrease in resistivity at the grain boundary regions and activation energy is believed to be caused by the diffusion from the highly conductive isolated areas present in the grain boundary toward the entire grain boundary area with increase in thermal treatment temperature.