Enhancement of piezoelectric properties by introducing heterogeneous structure

采用化学溶液沉积法制备了具有一定气孔或铂纳米颗粒的PZT薄膜，并用原子力显微镜(AFM)对其压电性能进行了测试。薄膜厚度约为300 nm。用扫描电子显微镜(SEM)和透射电子显微镜(TEM)对其微观结构进行了研究。通过改变旋涂速度来调节气孔的数量。最后估算了PZT薄膜的密度为0.92-0.98。另一方面，通过改变前驱体溶液的混合比例为0-9%来调节铂纳米粒子的量。结果表明，AFM估算的有效压电常数D33，AFM随着孔洞或铂纳米粒子数量的增加而增大。这些结果表明，非均相结构的引入增加了易被电场扭曲的不稳定晶格。

Pb(Zr,Ti)O3 (PZT) thin films with some amounts of pores or Pt nanoparticles were prepared by chemical solution deposition and their piezoelectric properties were evaluated by atomic force microscopy (AFM). Film thickness was approximately 300 nm. Their microstructures were also investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The amount of pores was adjusted by changing the speed of spin-coating. Finally, the densities of the PZT films were estimated to be 0.92-0.98. On the other hand, the amount of Pt nanoparticles was adjusted by changing the mixing ratios of precursor solutions to 0-9%. As a result, an effective piezoelectric constant d33,AFM estimated by the AFM was enhanced with increasing the amounts of pores or Pt nanoparticles. These results suggest that unstable lattices which were easily distorted with applying an electric field increased by introducing the heterogeneous structures.