【作者】 陈达；

【导师】 邹赫麟；

【作者基本信息】 大连理工大学 ， 测试计量技术及仪器， 2020， 硕士

【摘要】 本文分析了PZT材料的电学性能,探究了Pr掺杂对PZT薄膜各项性能的影响,优化了底电极、PZT薄膜和顶电极的图形化工艺,制作了压电微执行器,并对其振动性能进行了表征。主要研究内容如下所示:（1）研究Pr掺杂对PZT薄膜各项性能的影响。采用溶胶凝胶法按照化学式Pb_1.2-1.5xPr_xZr_0.52Ti_0.48O₃制备了不同Pr掺杂浓度的PPZT前驱体溶液,其中X=0、1、2、3、4、5;称取三水合醋酸铅药品时,采取铅过量20%的方法解决后续热处理过程中铅的挥发导致的薄膜内组分配比失衡的问题。采用多次旋凃-热处理的方式制得1μm厚的薄膜,热处理过程包括干燥去除水分、热解去除有机物和高温退火结晶。对PPZT薄膜的各项性能进行表征,实验结果表明,Pr掺杂浓度为2%的PPZT薄膜的综合性能最佳,其（100）晶向的择优取向度高达81.5%;横截面呈现出明显的致密钙钛矿柱状结构;介电常数最高,达到了1462.1,比未掺杂的PZT薄膜的介电常数（1324.7）提高了10.37%;剩余极化强度最大,达到了12.79μC/cm²,比未掺杂的PZT薄膜的剩余极化强度（7.83μC/cm²）提高了63.35%;经过10⁸次极化翻转后,剩余极化强度下降为初始值的61.4%,而未掺杂的PZT薄膜的剩余极化强度下降为初始值的39.5%。分析掺杂改性机理发现,三价态掺杂离子的引入会起到施主掺杂与受主掺杂的双重作用,对利用溶胶凝胶法制备的PZT薄膜性能的影响主要包括两个方面,一方面是引起薄膜内部的晶体结构发生变化,另一方面是改变内部电畴的翻转能力。通过对这两方面的影响进而改变薄膜的各项性能。（2）优化底电极、PZT薄膜和顶电极的图形化工艺。采用直流磁控溅射法工艺沉积Pt/Ti底电极和Pt顶电极。采用湿法腐蚀的方法对Pt/Ti底电极和PZT薄膜进行图形化,采用光刻、剥离工艺对Pt顶电极进行图形化。实验结果表明,Pt在王水中的腐蚀速率约为3.33nm/s,Ti在HF中的腐蚀速率约为5nm/s;PZT薄膜在配置的PZT腐蚀液中的平均腐蚀速率约为5.26nm/s。通过多次腐蚀-清洗-腐蚀的方法可以有效减小横向侧蚀。（3）制作压电微执行器并对其振动性能进行表征。对利用不同Pr掺杂浓度的PPZT薄膜制作的振动板施加幅值分别为5V、10V、15V、20V且频率为10kHz的正梯形波电压,实验结果表明,适量的Pr掺杂能够提高PZT薄膜的压电性能,电压为20V时,利用Pr掺杂浓度为2%的PPZT薄膜制作的压电微执行器的振幅最大,达到了414.5nm,比利用未掺杂的PZT薄膜制作的压电微执行器的振幅（298.1nm）提高了39%。更多还原

【Abstract】 This paper analyzed the electrical properties of PZT thin films,and explored the influence of Pr doping on the properties of them.The graphic processes of bottom electrode,PZT thin films and top electrode were optimized.The piezoelectric microactuators were fabricated and their vibration performances were characterized.The main research contents are shown below.（1）The influence of Pr doping on the properties of PZT films was studied.PPZT precursor solutions doped with different Pr concentrations were prepared by sol-gel method according to chemical formula Pb1.2-1.5x Pr_xZr_0.52Ti_0.48O₃,in which X=0,1,2,3,4 and 5.When weighing lead acetate trihydrate drugs,the method of lead excess of 20%was adopted to solve the problem of component ratio imbalance in the film caused by lead volatilization in the subsequent heat treatment.The PZT thin film with thickness of 1μm was prepared by multiple spins and heat treatment.The process of heat treatment includes drying to remove moisture,pyrolysis to remove organic matter and high temperature to anneal crystallization.The properties of PPZT thin films were characterized,and the experimental results showed that PPZT thin films doped with Pr concentration of 2%had the best comprehensive properties,where degree of preferential orientation of（100）crystal direction was up to 81.5%.The cross-section showed the obvious dense perovskite columnar structure.The dielectric constant was the highest,reaching 1462.1,which was 10.37%higher than that of undoped PZT thin film（1324.7）.The residual polarization intensity was the largest,reaching 12.79μC/cm²,which was 63.35%higher than that of the undoped PZT thin film（7.83μC/cm²）.After 10⁸ polarization reverses,the residual polarization strength decreased to 61.4%of the initial value,while the residual polarization strength of the undoped PZT thin film decreased to 39.5%of the initial value.In this paper,after analysis of doping modification mechanism,found that the introduction of three valence doped ions will play a dual role of donor-doping and acceptor-doping.The influence of this on the properties of PZT thin films prepared by sol-gel method mainly included two aspects:one was to change the crystal structure inside the films;the other was to change the turnover ability of internal electric domains.Through the influence of these two aspects,the properties of the films were changed.（2）The graphic technology of bottom electrode,PZT thin films and top electrode was introduced.The Pt/Ti bottom electrode and Pt top electrode were deposited by DC magnetron sputtering.The Pt/Ti bottom electrode and PZT film were graphically etched by wet corrosion.While the Pt top electrode was graphically etched by lithography and stripping.The experimental results showed that the corrosion rate of Pt in aqua aureus was about 3.33 nm/s,and that of Ti in HF was about 5 nm/s.The average corrosion rate of PZT thin films in the configured PZT corrosive liquid was about 5.26 nm/s.The lateral corrosion can be effectively reduced by means of repeated corrosion-cleaning-corrosion.（3）The piezoelectric microactuators were fabricated,whose vibration performance were characterized.A positive T-wave voltage with amplitude of 5V,10V,15V,20V and frequency of 10 kHz was applied to the vibration plates made of PPZT thin films with different Pr doping concentrations.The experimental results showed that proper Pr doping can improve the piezoelectric performance of PZT thin films.When the voltage was 20V,the amplitude of the piezoelectric microactuator made of PPZT thin film with Pr doped concentration of 2%was the highest,reaching 414.5 nm,which was 39%higher than that of the piezoelectric microactuator made of undoped PZT thin film（298.1 nm）.更多还原