溅射PZT薄膜的晶体结构和快速热处理

采用常温射频（ＲＦ）溅射法和快速热处理相结合的技术，在Ｐｔ／Ｔｉ／ＳｉＯ２／Ｓｉ衬底上，制备出具有铁电性的ＰＺＴ薄膜。研究了快速热处理工艺条件对ＰＺＴ薄膜性能的影响。通过Ｚ射线衍射法、ＳＥＭ和ＡＥＳ等方法，分析了ＰＺＴ薄膜的晶体结构、微结构、薄膜和电极间的界面效应。     

PZT／Si薄膜的扩散反应研究

运用ＸＰＳ和ＡＥＳ研究了ＰＺＴ膜／Ｓｉ在热处理过程中的薄膜及界面化学反应；在热处理过程中，气氛中的气通过ＰＺＴ的缺陷通道扩散到ＰＺＴ／Ｓｉ同旧，并与界面上的硅发生氧化反应形成ＳｉＯ２界面层。同时基底上的硅通过ＰＺＴ的缺陷扩散么样品表面形成ＳｉＯ２表面层。此外，在ＰＺＴ／Ｓｉ界面上，Ｔｉ的氧化物和Ｓｉ发生还原反应，形成了ＴｉＳｉｘ金属硅化物，并残留在ＰＺＴ膜层和和ＳｉＯ２界面层中。在ＰＺＴ膜层内，有     

Pt扩散阻挡层对PZT／Si薄膜化学结构和性能的影响

运用ＸＰＳ和ＡＥＳ研究了Ｐｔ扩散阻挡层对ＰＺＴ薄膜／Ｓｉ界面休学结构和性能的影响：在ＰＺＴ薄膜和Ｓｉ工间增加Ｐｔ扩散阻挡层，可以抑制ＴｉＣｘ物种和ＴｉＳｉｘ物种的形成，促进ＰＺＴ薄膜的形成反应。Ｐｔ扩散阻挡层的存在阻断了氧和Ｓｉ的相互扩散反应，促进ＰＺＴ物种形成钙钛矿型晶体结构，使得形成的ＰＴ薄膜具有和体相材料相摈 电常数和铁电性能。     

快速热处理对PZT薄膜的微结构及电性能的影响

采用改进的溶胶一凝胶技术,在Ｐｔ／Ｔｉ／ＴｉＯ２／ＳｉＯ２／Ｓｉ（１００）基片上制备了太电ＰＺＴ薄膜,用ＸＲＤ和ＡＦＭ技术分析了不同热处理工艺条件下ＰＺＴ薄膜的微观形貌变化及相结构演化,系统测试了ＰＺＴ薄膜的铁电性能。工艺－结构－性能研究结果表明：快速热处理工艺（ＲＴＡ）有利于ＰＺＴ薄膜保持较低的漏电流密度,热处理温度是影响晶粒大小的主要因素,而保温时间则对ＰＺＴ薄膜的致密性、晶粒均匀度和晶界结合     

脉冲激光淀积法在Pt/TiO_2/SiO_2/Si(001)衬底上制备Pb(Ta_(0.05)Zr_(0.45)Ti_(0.50))O_3薄膜的铁电性质研究

用脉冲激光淀积方法在Ｐｔ／ＴｉＯ２／ ＳｉＯ２／ Ｓｉ（００１） 衬底上制备了掺Ｔａ 的ＰＺＴ 薄膜。此薄膜显示了理想的铁电性。漏电流特性表明这种异质结构中Ｓｃｈｏｔｔｋｙ 场发射机制起主要作用。扫描电镜形貌照片表明ＰＺＴ 薄膜结晶很好并且异质结构界面无明显扩散。     

PZT／Si界面氧化反应机理及动力学研究

运用俄歇电子能谱深度剖析和线形分析研究了ＰＺＴ／Ｓｉ界面氧化反应的机理和动力学过程，研究结果表明，在ＰＴ／Ｓｉ样品的热处理过程中，环境气氛中的氧可以透过ＰＺＴ薄膜层扩散到ＰＴ／Ｓｉ界面，并与硅基底反庆形成ＳｉＯ２界面层，界面氧化反应由氧在ＰＴ层和ＳｉＯ２层中的扩散过程所控制。     

脉冲激光淀积法在Pt／TiO2／SiO2／Si（001）衬底上制备Pb（Ta0.05Zr0.45T …

用脉冲激光淀积方法在Ｐｔ／ＴｉＯ２／ＳｉＯ２／Ｓｉ（００１）衬底上制备了掺Ｔａ的ＰＺＴ薄膜,此薄膜显示了理想的铁电性。漏电流特性表明这种异质结构中Ｓｃｈｏｔｔｋｙ场发射机制起主要作用。扫描电镜形貌照射表明ＰＺＴ薄膜结晶很好并且异质结构界面无明显扩散。     

溅射工艺参数对PZT铁电薄膜相变过程的影响

采用射频磁控溅射工艺,在（１１１）Ｐｔ／Ｔｉ／ＳｉＯ２／Ｓｉ衬底上用ＰＺＴ（５３／４７）陶瓷靶制备铁电薄膜。用快速光热退火炉对原位沉积的薄膜进行ＲＴＡ处理。     

钇改性PZT薄膜的极化印刻研究

铁电ＰＺＴ薄膜的极化印刻（ｉｍｐｒｉｎｔｉｎｇ）是ＰＺＴ不挥发存储器失效的重要原因之一．本文研究了不同钇量改性的ＰＺＴ（４０／６０）铁电薄膜在高温（１２０℃）和偏置电压下的极化印刻特性,发现适量的钇掺杂,改善了ＰＺＴ薄膜电容器单元的极化印刻．     

高取向度PZT铁电薄膜的研制

用无机盐替代锆卤,通过Ｓｏｌ＝Ｇｅｌ方法,合成均匀、稳定的ＰＺＴ溶胶。采用Ｐｔ／Ｔｉ／ＳｉＯ２／Ｐｉ基片加入ＰＴ过渡层,经快速热处理制备出沿（１００）高度定向的ＰＺＴ陶瓷薄膜,此薄膜具有良好的铁电性能。     

Deflection of wafers and cantilevers with Pt/LNO/PZT/LNO/Pt/Ti/SiO2 multilayered structure

The present paper describes a Pt/LNO/PZT/LNO/Pt/Ti/SiO₂ multilayers deposited on 4-inch Si wafers. We have evaluated the variation of the deflection of the Si wafers with deposition of each of the thin films. The deposition of the multilayers has resulted in downward deflection (center is higher than edge) of the Si wafers. The multilayers have been also deposited onto SOI wafers and fabricated into piezoelectric micro cantilevers through MEMS bulk micromachining. The micro cantilevers have shown the upward deflection. We have characterized the ferroelectric and piezoelectric properties of the PZT thin films through electrical tests of the micro cantilevers. The dielectric constant, saturation polarization, remanent polarization and coercive field were measured to be 1050, 31.3 μC/cm², 9.1 μC/cm² and 21 kV/cm, respectively. The transverse piezoelectric constant, d₃₁, was measured to be − 110 pm/V from the DC response of the micro cantilevers.     

Ferroelectric and piezoelectric behavior of (111)-oriented Pb(ZrxTi1−x)O3 thin films on cobalt ferrite nano-seed layered Pt(111)/Si substrate

Perfect (111)-oriented Pb(Zr_xTi_1?x)O₃ (PZT) thin films were grown on cobalt ferrite buffered Pt(111)/Ti/SiO₂/Si substrate by pulsed laser deposition method using various targets with different Zr/Ti ratios ranging from 30/70 to 70/30. The results of X-ray diffraction analyses indicated that the composition of morphotropic phase boundary in the present PZT films is same as the bulk PZT (Zr/Ti = 52/48). The effect of Zr/Ti ratio of the PZT films was investigated by the ferroelectric domain structure and the piezoelectric characteristics of the films by piezoresponse force microscopy, as well as polarization measurement. The results revealed that the present tetragonal PZT film has a higher ferroelectric domain switching than rhombohedral one and the film with composition of Zr/Ti = 52/48 showed relatively high value of squareness of P–E loop and E_c as well as high piezoresponse.     

力电多场鼓包法测定PZT铁电薄膜的横向压电系数

为表征Pb(Zr_(0.52)Ti_(0.48))O_3(PZT)薄膜的横向压电性能,以纯力场鼓包测试模型和铁电薄膜材料压电方程为基础,推导了PZT铁电薄膜的力电耦合鼓包本构模型。采用溶胶-凝胶法制备了PZT铁电薄膜,并通过化学腐蚀法获得PZT薄膜鼓包样品。在外加电压为0~14V的条件下进行鼓包测试。结果表明,在纯力场作用下,PZT薄膜的弹性模量和残余应力分别为91.9GPa和36.2MPa;随着电压从2V变化到14V,PZT薄膜的横向压电系数d31从-28.9pm/V变化到-45.8pm/V。本工作所发展的力电耦合鼓包测试技术及力电耦合鼓包本构模型为评价铁电薄膜材料的横向压电性能提供了一种有效的分析方法。     

Enhanced ferro- and piezoelectric properties in (100)-textured Nb-doped Pb(ZrxTi1 − x)O3 films with compositions at morphotropic phase boundary

To develop high-performance piezoelectric films on conventional Pt(111)/Ti/SiO₂/Si(100) substrates, sol-gel-derived highly [100]-textured Nb-doped Pb(Zr_xTi_1 − x)O₃ (PNZT) thin films with different Zr/Ti ratios ranging from 20/80 to 80/20 were prepared and characterized. The phase structure, ferroelectric and piezoelectric properties of the PZNT films were investigated as a function of Zr/Ti ratios, and it was confirmed that there was distinct phase transition of the PNZT system from tetragonal to rhombohedral when the Zr/Ti ratio varied across the morphotropic phase boundary (MPB). The Nb-doped PZT films showed enhanced remanent polarization but reduced coercive field, whose best values reached 75 μC/cm² and 82 kV/cm, respectively at the composition close to MPB. In addition, the [100]-textured PNZT film at MPB also shows a high piezoelectric coefficient up to 161 pm/V. All these properties are superior to those for undoped PZT films.     

电极对PZT铁电薄膜的微观结构和电性能的影响

采用溶胶—凝胶(sol—gel)工艺分别在Pt／Ti／SiO2／Si和LNO／Si电极上制备Pb(Zr0．53，Ti0．47)O3(PZT)铁电薄膜。研究了不同电极材料对PZT铁电薄膜的微结构及电性能的影响。(100)择优取向的PZT／LNO薄膜的介电性能和铁电性能较(111)／(100)取向的PZT／Pt薄膜略有下降，但在抗疲劳特性和漏电流特性方面都有了很大提高。PZT／LNO薄膜10m次极化反转后剩余极化几乎保持未变，直至10^12次反转后，剩余极化仅下降了17％。     

Preparation of (001)-oriented Pb(Zr,Ti)O/sub 3/ thin films and their piezoelectric applications

Preparation of (001)-oriented Pb(Zr,Ti)O₃ (PZT) thin films and their applications to a sensor and actuators were investigated. These thin films, which have a composition close to the morphotropic phase boundary, were epitaxially grown on (100)MgO single-crystal substrates by RF magnetron sputtering. These (001)-oriented PZT thin films could be obtained on various kinds of substrates, such as glass and Si, by introducing (100)-oriented MgO buffer layers. In addition, the (001)-oriented PZT thin films could be obtained on Si substrates without buffer layers by optimizing the sputtering conditions. All of these thin films showed excellent piezoelectric properties without the need for poling treatment. The PZT thin films on the MgO substrates had a high piezoelectric coefficient, d₃₁, of -100 pm/V, and an extremely low relative dielectric constant, epsiv_r, of 240. The PZT thin films on Si substrate had a very high d₃₁ of -150 pm/V and an epsiv_r = 700. These PZT thin films were applied to an angular rate sensor with a tuning fork in a car navigation system, to a dual-stage actuator for positioning the magnetic head of a high-density hard disk drive, and to an actuator for an inkjet printer head for industrial on-demand printers.     

Preparation of (001)-oriented Pb(Zr,Ti)O3 thin films and their piezoelectric applications

Preparation of (001)-oriented Pb(Zr,Ti)O(3) (PZT) thin films and their applications to a sensor and actuators were investigated. These thin films, which have a composition close to the morphotropic phase boundary, were epitaxially grown on (100)MgO single-crystal substrates by RF magnetron sputtering. These (001)-oriented PZT thin films could be obtained on various kinds of substrates, such as glass and Si, by introducing (100)-oriented MgO buffer layers. In addition, the (001) oriented PZT thin films could be obtained on Si substrates without buffer layers by optimizing the sputtering conditions. All of these thin films showed excellent piezoelectric properties without the need for poling treatment. The PZT thin films on the MgO substrates had a high piezoelectric coefficient, d(31), of -100 pm/V, and an extremely low relative dielectric constant, epsilon(r), of 240. The PZT thin films on Si substrate had a very high d(31) of -150 pm/V and an epsilon(r) = 700. These PZT thin films were applied to an angular rate sensor with a tuning fork in a car navigation system, to a dual-stage actuator for positioning the magnetic head of a high-density hard disk drive, and to an actuator for an inkjet printer head for industrial on-demand printers.     

Fabrication of single crystal PZT thin films on glass substrates

 We have successfully transferred heteroepitaxial Pb(Zr,Ti)O₃ (PZT) thin films from MgO substrates on to glass substrates. The transferred PZT thin films exhibit single crystal structure with ferroelectric properties similar to the as-grown epitaxial films. The transferring process comprises coating of Cr-metallized surface of epitaxial PZT thin films, pressing and cementing the Cr-metallized surface on to the glass substrates by silicone rubber, and removing the MgO substrates by chemical etching. This process realizes a fabrication of high-temperature processed PZT thin films onto the glass at room temperature. The process is also available for the transformation of PZT thin films on organic film sheet. The present transfer process reduces the effects of the inevitable strain and/or constraint to rigid substrates for heteroepitaxial growth and has a potential for integration of single crystal piezoelectric PZT devices onto a wide variety of MEMS.     

溶胶-凝胶法制作PZT微驱动器的研究

采用溶胶-凝胶法(Sol-gel)制备了PZT压电薄膜,利用PZT的压电效应制作以PZT薄膜为驱动的V型阀微驱动器.针对微驱动器的关键结构驱动膜,探索了Si/SiO2/Ti/Au/PZT/Cr/Au多层驱动膜结构制备方法,解决了在硅基底上制备PZT薄膜的问题,同时详细探讨了硅各向异性刻蚀微驱动器的关键部件驱动腔、单向阀的工艺,解决了集成制作的V型阀微驱动器的关键工艺问题,并通过SEM照片对V型阀和多层驱动膜进行了表征.研究结果表明,采用MEMS与IC技术结合的方法成功地完成了微驱动器的研制,得到的驱动腔硅杯平坦均匀.在V型阀微驱动器整体设计中需要的硅片数目少,降低了器件的复杂性,可以满足低功耗、小型化和批量生产的要求.