Effect of bottom electrodes on structures and electric properties of PLT ferroelectric thin films

Abstract

Lead lanthanum titanate (PLT) thin film with 10 at.% of La and 15 at.% of excess Pb were deposited on Pt/Ti electrodes with different thickness of Ti layer by metallo-organic decomposition (MOD) process. X-ray diffraction (XRD) and scanning electron microscopy (SEM) have been applied to investigate the micro structure and morphology of the PLT thin films. The grain sizes of PLT thin films are between 0.9/spl sim/1.5 /spl mu/m. The thickness of the Ti layer has a dominant effect on the dielectric and ferroelectric properties of the PLT films. The dielectric constants of the thin films annealed at 550/spl deg/C for 1 hr are between 510/spl sim/580, the dielectric loss tangent is less than 2%. The remanent polarization is between 6.3/spl sim/7.6 /spl mu/m/cm/sup 2/ and the coercive field is about 68.9/spl sim/83.7 kV/cm at 1 kHz.