用sol—gel法分别制备了直接沉积在Pt/Ti/SiO2/Si衬底上和加入了TiO2种子层的Bi3.15Nd0.85Ti3O12(BNT)铁电薄膜,研究了种子层对BNT薄膜结构和电学性能的影响.XRD结果表明直接沉积在Pt/Ti/SiO2/Si衬底上的BNT薄膜具有(117)和(001)的混合取向,而加入TiO2种子层之后薄膜的最强峰为(200)取向;FE-SEM显示具有TiO2种子层的BNT薄膜,其表面主要是由具有非C轴取向的晶粒组成且更为致密;直接沉积的BNT薄膜和具有TiO2种子层的BNT薄膜的剩余极化Pr值分别为26和43.6μC/cm^2,矫顽场强&分别为91和80.5kV/cm;疲劳测试表明两种薄膜均具有良好的抗疲劳特性,TiO2种子层的引入并没有降低BNT薄膜的疲劳特性;两种薄膜的漏电流密度均在10^-6-10^-5A/cm^2之间.
Bi3.15Nd0.85Ti3O12 (BNT) thin films with and without a TiO2 seeding layer were fabricated on Pt/Ti/SiO2/Si substrates by sol-gel method at 750℃. The effect of seeding layer on structural and electrical properties of BNT thin films was investigated. X-ray diffraction pattern shows that the BNT thin film deposited directly on Pt/Ti/SiO2/Si substrate exhibits predominantly (117) and (001) orientation while the BNT thin film grow on Pt/Ti/SiO2/Si substrate with a TiO2 seeding layer show a highly a axis orientation with the (200) strongest peak. The BNT thin film with a TiO2 seeding layer is a more dense and homogeneous than that deposite directly on Pt/Ti/SiO2/Si substrate. The Pr and Ec values of BNT films with and without TiO2 layer are 43.6 and 26μC/cm^2, and 91 and 80.5kV/cm, respectively. The fatigue test exhibits a very strong fatigue endurance up to 109 cycles for both films. The addition of TiO2 seeding layer does not decrease the fatigue characteristic of BNT thin film. The leakage current density are generally in the order of 10^-6 - 10^-5A/cm^2 for both samples.