Comparative study of effects of Mo and W dopants on the ferroelectric property of Pb(Zr0.3Ti0.7) thin films

Abstract

Pb(Zr0.3Ti0.7)O3 thin films, respectively, doped with 1 mol% W and 1 mol% Mo have been deposited on the LaNiO3 bottom electrodes using pulse laser deposition. The x-ray diffraction analyses revealed that both dopants induced (1 1 0) orientation of the perovskite structures. Compared with the undoped PZT films, the doped PZT films showed smoother and denser surfaces. The XPS measurements indicated that W possessed a valence state of +6 in the PZTW films, but Mo showed mixed valence states of +4 and +6. The hysteresis loops and fatigue results of the undoped, the W-doped (PZTW) and the Mo-doped PZT (PZTM) films were obtained. While both the two doped films revealed better fatigue behaviour than undoped PZT, the PZTW film had a slow fatigue rate in comparison with the PZTM film, which is consistent with our previous theoretical predictions. © 2008 IOP Publishing Ltd.