采用溶胶-凝胶法(Sol-Gel)在Pt/Ti/SiO2/Si(100)衬底上制备了0.94(Na0.5 Bi0.5)TiO3-0.06BaTiO3(BNT-BT6)薄膜,研究了不同退火时间对其微结构和压电性能的影响.X射线衍射(XRD)结果表明,制备的BNT-BT6薄膜为钙钛矿型铁电薄膜,随着退火时间的延长,晶粒尺寸略有增加.原子力显微镜(AFM)结果表明,制备的薄膜表面比较平整、无裂缝.随着退火时间的延长,薄膜的粗糙度有所增加.在退火时长为60 min时薄膜表面具有最佳的均一性,在退火时间为90 min时薄膜均一性最差;优化退火时间,可提高薄膜结晶程度,避免焦绿石相的生成,进而提高BNT-BT6薄膜压电性能.压电力显微镜(PFM)结果表明,BNT-BT6薄膜的电畴为多畴结构.在不同退火时间下均有明显的压电响应,特别是在退火时间为60 min时,BNT-BT6原始电畴有着最高的振幅强度.在30 min、40 min、60 min和90 min退火时间时,其平均压电系数d33分别为48 pm/V、157 pm/V、186 pm/V和142 pm/V.%0.94(Na0.5 Bi0.5 )TiO3-0.06BaTiO3 (BNT-BT6)thin films were fabricated on Pt/Ti/SiO2/Si(100) substrate by sol-gel method.The effects of annealing time on microstructure and piezoelectric properties of BNT-BT6 thin films were investigated.X-ray diffraction (XRD)analysis showed that the thin films was perovskite structure. With the increase of annealing time,the grain size of thin films increased not clearly.The atomic force microscope (AFM)results indicated the surface of BNT-BT6 thin film was smooth,uniform and crack free.The surface rough-ness of BNT-BT6 thin films increased with annealing time increasing,and the homogeneity of surface was best at an-nealing time 60 min.The worst homogeneity of surface was at annealing time 90 min.By optimizing annealing time, crystallinity of thin film can be increased and pyrochlore phase can be avoided,which provides a benefit to piezoelectric properties of BNT-BT6 thin films.The piezoresponse force microscopy (PFM)analysis suggested that the domain of BNT-BT6 thin film was polydomain structure and at annealing time 60 min,the BNT-BT6 thin film had strongest pie-zoresponse.The average piezoelectric coefficient d33 of BNT-BT6 films were 48 pm/V,157 pm/V,186 pm/V and 142 pm/V at annealing time 30 min,40 min,60 min and 90 min respectively.
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