具有ABO3型钙钛矿结构的Pb(ZrxTi1-x)O3(PZT)展示出良好的铁电极化性能,是使用最广的铁电材料.然而,在将它应用于铁电存储时,PZT薄膜遭遇到极化疲劳问题而被SrBi2Ta2O9(SBT)等铁电体所替代,这一问题至今未能得到妥善解决.文章首先通过变温极化疲劳实验充分理解PZT极化疲劳的基本过程,然后有针对性地进行材料设计,获得基本无极化疲劳的PZT铁电薄膜.
Perovskite Pb ( ZrxTi1-x ) O3 (PZT) represents one of the most extensively utilized ferroelectrics, in spite of its lead contamination. However, its application in ferroelectric random access memories (FeRAMs) has been hindered due to serious polarization fatigue upon repeated domain switching, so that it has eventually been replaced by layered perovskite ferroelectric Sr/BiTa5O9 (SBT), among others. Since polarization fatigue remains an unsolved physical issue we address this problem by a comprehensive approach in which the associated mechanisms are investigated by fatigue testing at different temperatures, amplitudes and frequencies of the electric field. As a result, we have developed a novel strategy by which the fatigue of PZT thin films deposited on Pt-coated Si wafers can be essentially suppressed.