Effects of (100)-Textured LaNiO₃ Electrode on Crystallization and Properties of Sol-Gel-Derived Pb(Zr_0.53Ti_0.47)O₃ Thin Films

Abstract

Sol-gel-derived thin films of Pb(Zr 0.53 Ti 0.47 )O 3 (PZT) were spin-coated onto the (100)-textured LaNiO 3 (LNO) electrode which was deposited on a Pt/Ti/SiO 2 /Si substrate by rf magnetron sputtering at 350° C. The annealing temperature for obtaining a perovskite PZT film on LNO was reduced by about 50° C compared with that direct deposition on Pt. Highly a - and c -axis-oriented PZT films were obtained by annealing at temperatures above 500° C, while randomly oriented films were formed on Pt electrode. Moreover, the grain size of PZT films grown on LNO was smaller than that of films on Pt. The dielectric constant, ε r , remanent polarization, P r , and coercive field, E c , of PZT films on LNO changed markedly with the annealing conditions. ε r increased and both P r and E c markedly decreased with increasing annealing temperature or time, which was attributed to the out-diffusion of LaNiO 3 into PZT films during annealing. Use of the LNO layer as a bottom electrode was also found to greatly improve the fatigue property of PZT films.