Fatigue in artificially layered Pb(Zr,Ti)O3 ferroelectric films

We have performed fatigue tests on lead zirconate titanate (PZT) multilayers having stacks of Pb(Zr0.8Ti0.2)O-3/Pb(Zr0.2Ti0.8)O-3 with repeated distances of 12 formula groups. The results are compared with single-layer n-type (0.5 at. % Ta-doped) PZT films. We conclude that fatigue is dominated by space-charge layers in each case, but that in the multilayer such space charge accumulates at the layer interfaces, rather than at the electrode-dielectric interface. The model, which includes both drift and diffusion, is quantitative and yields a rate-limiting mobility of 6.9+/-0.9x10(-12) cm(2)/V s, in excellent agreement with the oxygen vacancy mobility for perovskite oxides obtained from Zafar (C) 2002 American Institute of Physics.