新改-济南大学毕业论文于胜兰2011.doc

摘 要 为了对Bi3.15Nd0.85Ti3O12（BNT0.85）铁电薄膜结构和性能的影响，本论文采用-凝胶法(Sol-Gel)在Pt/Ti/SiO2/Si制备了。XRD425℃的制备工艺条件下，分别在退火温度为560℃保温时间为180s和退火温度为550℃保温时间为300s的条件下，制备出了 BNT0.85薄膜。通过测试薄膜的铁电性能可以看出，退火温度为560℃保温时间为180s条件下所得薄膜铁电性能较好，并且，随着电压的增大，BNT0.85薄膜剩余极化Pr回线矩形度逐渐增加560℃保温时间为180s条件下所得薄膜压电性能较好，该条件下 BNT0.85薄膜425℃、退火温度为560℃及保温时间为180s的制备工艺条件下，获得了a轴取向择优Bi3.15Nd0.85Ti3O12薄膜；-凝胶法；电滞回线  ABSTRACT In this paper ,in order to explore the effect of seeding layer on the structure and properties of Bi3.15Nd0.85Ti3O12 (BNT0.85) ferroelectric thin films, we deposited the seeding layer on Pt/Ti/SiO2/Si substrates using sol-gel method at different thickness, pretreatment temperatures, annealing temperatures and heat preservation time. XRD patterns show that different experimental conditions have an important effect on the crystallization of BNT0.85 films, and in the condition of each layer thickness of 70nm and pretreatment temperature of 425 ℃, BNT0.85 ferroelectric thin films were prepared at annealing temperatures of 560℃ for 180s and 550℃ for 300s, respectively. The analysis of ferroelectric properties shows that, the ferroelectric properties of BNT0.85 films prepared at annealing temperatures of 560℃ for 180s are better, and their values of the remanent polarization (Pr) and the rectangular of the hysteresis loop improve with the increase of the voltage applied. The analysis of piezoelectric properties shows that, the piezoelectric properties of BNT0.85 films prepared at annealing temperatures of 560℃ for 180s are also better, their full width at half maximum (FWHM) of the peak is smaller, the peak-to-peak distance is larger, and they have almost the same piezoresponse under positive and negative voltages and excellent uniformity. Therefore, BNT0.85 ferroelectric thin films which were prepared in the condition of each layer thickness of 70nm and pretreatment temperature of 425 ℃ at annealing temperatures of 560℃ for 180s are highest predominantly (100)-oriented films with better ferroelectric and pie