Preparation and electrical properties of sol–gel derived (1−x)Pb(Sc1/2Nb1/2)O3−xPbTiO3 (x=0.6) thin films

The films of (1−x)Pb(Sc1/2Nb1/2)O3−xPbTiO3 (x=0.6, PSNT(40/60)) were successfully deposited on Pt/Ti/SiO2/Si substrates via spin coating method. Using combination of homogeneous precursor solutions and two-step heat treatment, it was possible to obtain the PSNT(40/60) thin films of perfect perovskite phase with virtually no pyrochlore phase after annealing just above 550°C. The root-mean-square surface roughness of a 240-nm-thick film was 3 nm as measured by atomic force microscope (AFM). The PSNT(40/60) films annealed at 650°C showed a well-saturated hysteresis loop at an applied voltage of 7 V with remnant polarization (Pr) and coercieve voltage (Vc) of 14 μC/cm2 and 1.5 V. The leakage current density was lower than 10−6 A/cm2 at an applied voltage of 7 V.