保持总的工作气压不变,在不同氩氧比条件下,采用射频磁控溅射法在铝电极层上制备了ZnO薄膜。用X射线衍射(XRD)、原子力显微镜(AFM)和压电响应力显微镜(PFM)分析了ZnO薄膜的择优取向、表面形貌和压电响应,并通过垂直PFM(VPFM)和水平PFM(LPFM)相位图研究了ZnO晶粒的极化特性。结果表明,氩氧比对ZnO薄膜的晶体结构和压电特性有显著影响,其中在氩氧比1∶1的条件下制备的ZnO薄膜具有最大的VPFM振幅和最佳的极化取向一致性。
With the same total working pressure,ZnO thin films were prepared on aluminum electrode layers by radio frequency magnetron sputtering at different Ar∶ O2 molar ratios. The preferred orientation,surface topography and piezoresponse were analyzed using X-ray diffraction( XRD), atom force microscopy( AFM) and piezoresponse force microscopy( PFM). The polarization characteristics of the ZnO grains were studied by vertical PFM( VPFM) and lateral PFM( LPFM) phase diagrams. The results show that the Ar∶ O2 molar ratio has great influence on the crystal structure and piezoelectric properties of the ZnO thin films,and among the samples,the one deposited at the Ar ∶ O2 molar ratio of 1 ∶ 1 shows the greatest VPFM amplitude and the best polarization orientation uniformity.