直流磁控反应溅射制备IrO2薄膜

为研究氧化依（ＩｒＯ_２）对ＰＺＴ铁电薄膜疲劳性能的影响,利用直流（ＤＣ）磁控反应溅射（ｓｐｕｔｔｅｒｉｎｇ）工艺成功地在ＳｉＯ_２／Ｓｉ（１００）衬底上制得了高度取向的ＩｒＯ_２薄膜．并在其上制成ＰＺＴ铁电薄膜．讨论了溅射参数（溅射功率、 Ａｒ／Ｏ_２比、衬底温度）以及退火条件对氧化铱薄膜的结晶、取向和形态的影响．     

钛酸钡铁电薄膜的常压MOCVD制备及其物理性质的研究

本文报道了用常压金属有机化学气相沉积（ＡＰＭＯＣＶＤ）法在Ｓｉ衬底上制备高质量的钛酸钡铁电薄膜，钡的β－二酮螯合物（Ｂａ（ＤＰＭ）２）和异丙氧基钛（ＴＩＰ）作为金属有机源，在衬底温度为７００℃时，在Ｓｉ（１００），薄膜具有完全的（００１）取向，其介电常数（ε）为１０７。研究了衬底温度与薄膜的结晶性和取向性的关系；讨论了半导体衬底对酸钡铁电薄膜物理性质的影响，得到了薄膜的剩余自发极化强度（Ｐｒ）为２     

直流磁控反应溅射制备IrO2薄膜

为研究氧化铱（ＩｒＯ２）对ＰＺＴ铁电薄膜疲性能的影响。利用直流（ＤＣ）磁控反应溅射（ｓｐｕｔｔｅｒｉｎｇ）工艺成功地在ＳｉＯ２／Ｓｉ（１００）衬底上制得了高度取向的ＩｒＯ２薄膜,并在其上制成ＰＺＴ铁电薄膜,讨论了溅射参数（溅射功率、Ａｒ／Ｏ２比、衬底温度）以及退火条件对氧化铱薄膜的结晶,取向和形态的影响。     

水热法制备PLZT多元铁电薄膜的研究

研究了在水热条件下制备ＰＬＺＴ（８／６５／３５）多元铁电薄膜的优化工艺条件。讨论了反应温度,反应历程,反应时间等不同工艺条件对ＰＬＺＴ多元铁电薄膜结构、结晶取向的影响。结果表明,采用两步法合成工艺能够在Ｔｉ基片上制备出纯钙钛矿相结构,粒径为１μｍ,薄膜厚度为５μｍ介电数为ε＝４５０的ＰＬＺＴ（８／６５／３５）多元铁电薄膜。     

PLZT（28／0／100）薄膜的溶胶－凝胶制备技术及显微结构

用溶胶—凝胶技术及回旋法，在石英玻璃和单晶ｓｉ基片上制备ＰＬＺＴ（２８／０／１００）多晶薄膜；在ＳｒＴｉＯ３和α－Ａ１２Ｏ３单晶基片上外延生长择优取向薄膜．其外延关系分别为（１００）ＰＬＺＴ（２８／０／１００）／／（１００）ＳｒＴｉＯ３和（１００）ＰＬＺＴ（２８／０／１００）／／（０００１）Ａｌ２Ｏ３．用ＩＲ，ＸＲＤ．ＲＨＥＥＤ，ＳＥＭ和ＳＩＭＳ分析凝胶中杂质、凝胶的分子结构和薄膜的显微结构．结果表明，用溶胶—凝胶技术能制备出显微结构良好的多组份陶瓷薄膜．     

掺锡氧化铟基底上锆钛酸铅铁电薄膜的制备与表征

用溶胶-凝胶工艺在掺锡氧化铟导电氧化物基底上制备了锆钛酸铅（PZT）铁电薄膜．采用快速热处理工艺改进铁电薄膜的晶格取向，用X射线衍射仪分析了薄膜的结晶取向，分别基于Al／PZT／ITO，1TO／PZT／1TO电容结构利用Sawyer-Tower电路原理测试了薄膜的铁电性能．结果表明，在磁控溅射法生长的1TO表面能够制备出具有钙钛矿结构的（110）取向的PZT铁电薄膜，所得薄膜的相对介电常数达到1000，剩余极化强度Pr达到和Pt基底上接近的15．2uc／cm^2，矫顽场强Ec达到70．8kV/cm．并且利用TF Analyzer 2000铁电分析仪测试了PZT铁电薄膜的疲劳特性，发现ITO底电极上PZT薄膜经过108次反转后，剩余极化强度仅下降15％．研究表明：磁控溅射法制备的掺锡氧化铟透明导电薄膜ITO可以作为铁电薄膜的上下电极．     

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。     

激光脉冲沉积制备钛酸锶钡薄膜及其介电调协特性

在Pt（111）／Ti／SiO2／Si（100）衬底上,用脉冲激光沉积工艺制备出了高度a轴取向生长的（Ba0.65Sr0．35）TiO3（BsT）薄膜。薄膜为柱状生长的纳米晶粒,平均晶粒尺寸为50nm。在外加电场254kV／cm时,BST薄膜的相对介电常数与介电调谐率为810和76．3％。高的介电调谐率主要是BST薄膜具有高度a轴取向的柱状生长晶粒,因为来自沿平面c轴极化而产生的内部应力,在电场作用下,获得了高介电调谐率。     

氧离子束辅助激光制备具有组构的YBCO薄膜

应用氧离子束辅助准分子脉冲激光沉积薄膜技术,先在ＮｉＣｒ合金（Ｈａｓｔｅｌｌｏｙ ｃ－２７５）基底上在室温下淀积具有平面织构的钇稳锆（ＹＳＺ） 缓冲层薄膜,再在 ＹＳＺ／ＮｉＣｒ基底上在 ７５０℃下制备具有平面织构和高临界电流密度的 ＹＢａ２Ｃｕ３Ｏ７－Ｘ（ＹＢＣＯ）薄膜、 ＹＳＺ和 ＹＢＣＯ薄膜都为 ｃ－轴取向和平面织构的, ＹＳＺ（２０２）和 ＹＢＣＯ（１０３）的 Ｘ射线扫描衍射峰的全宽半峰值分别为 １８＇和 １１＇．ＹＢＣＯ薄膜的临界温度和临界电流密度分别为 ９０Ｋ（Ｒ＝０）和 ７．９ｘ１０５Ａ／ｃｍ２（７７Ｋ,零磁场）．     

沉积条件对RF反应溅射多晶ZnO薄膜结构的影响

采用ＲＦ反应溅射法在Ｓｉ（１１１）、玻璃衬底上制备了具有良好Ｃ轴承向的多晶ＺｎＯ薄膜。用ＸＲＤ分析了沉积条件（衬底温度、工作气体中的氧与氩气压比和衬底种类）对样品结构的影响,发现（１）薄膜的取向性随着衬底温或高而增强,超过４００℃后薄膜质量开始变差;（２）工作气体中氧与氩气压比（Ｐｏ２／ＰＡｒ）为２：３时,薄膜取向性最好;（３）薄膜晶粒尺寸１１－３４ｎｍ,相同沉积条件下,单晶硅衬底样品（００２）衍     

Effect of nanoparticles on ferroelectric and electrical properties of novel PMNT thin-films

This work studies the impact of adding nanoparticles to high-k PMNT (lead magnesium niobate-lead titanate, Pb(Mg_0.33Nb_0.67)_0.65Ti_0.35O₃) thin films. PMNT thin films were grown on Pt(111)/TiO₂/SiO₂/Si substrate using a sol-gel technique. Ligand stabilised PMNT nanoparticles were added to the sol-gel material with the aim of seeding the crystallization process. The measurements show that use of nanoparticles in PMNT thin films influences the remanent polarization, coercive field and dielectric constant. These characterization results support the ongoing investigation of the material ferroelectric and electrical properties which are necessary before the novel dielectric can be used in silicon applications.     

Improvement of the remnant polarization of 0.65Pb(Mg1/3Nb2/3)O3-0.35PbTiO3 thin films in a multilayer composite

It has been previously reported that the remnant polarization of 0.65Pb(Mg_1/3Nb_2/3)O₃-0.35PbTiO₃ (PMNT) thin films on Si-based substrates is much lower than that of bulk ceramics with the same composition, which is a problem for its integration in microdevices. The preparation of multilayer composites of PMNT and PbTiO₃ layers, which maintain large remnant polarization values even for the thinnest films, is explored in this work as an alternative for obtaining PMNT-based films with enhanced remanence. The multilayer composite thin films were fabricated onto Pt/TiO₂/SiO₂/Si (100) substrates by Chemical Solution Deposition. The deposited layers are ultrathin and the results show that there is no significant interdiffusion among them. Although the typical constraints related to the small grain size found in ultrathin layers and the associated lack of ferroelastic domains are present, the results show an improvement of the remanence of the PMNT layer in the multilayer composite film and that these composites can be good candidates for the integration of PMNT in devices.     

Properties of multilayer composite thin films based on morphotropic phase boundary Pb(Mg1/3Nb2/3)O3-PbTiO3

It has been reported that ferroelectric and piezoelectric properties of Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃ (PMNT) thin films, with compositions close to the morphotropic phase boundary (MPB), show lower values than those reported for bulk ceramics with the same composition, which has been attributed to a reduction of the remnant polarization caused by the small size of the grains in the films. An alternative has been proposed to take full advantage of the excellent piezoelectric properties of polycrystalline PMNT in thin film form: a multilayer configuration that uses ferroelectric layers with large remnant polarization, in this case PbTiO₃, to generate an internal electric bias within the PMNT layers and, thus, anchor an induced polarization on them, resulting in a consequent large piezoelectric behavior. The detailed study of the properties of these multilayer composite films reveals the complex correlations that arise in these heterostructures, which are key for the design of optimized piezoelectric films based on MPB PMNT.     

The influences of rapid-thermal annealing on the characteristics of Sr0.6Ba0.4Nb2O6 thin film

The Sr0.6Ba0.4Nb2O6 (SBN) thin films were successfully prepared on Pt/Ti/Si and SiO2/Si/Al substrates and crystallized subsequently using rapid thermal annealing (RTA) process in ambient atmosphere for 1 min. The surface morphologies and thicknesses of as-deposited and annealed SBN thin films were characterized by field emission scanning electron microscopy, and the thickness was about 246 nm. As compared with the as-deposited SBN thin films, the RTA-treated process had improved the crystalline structures and also had large influence on the crystalline orientation. When the annealing temperatures increased from 700 degrees C to 900 degrees C, the diffraction intensities of (410) and (001) peaks apparently increased. Annealed at 900 degrees C, the (001) peak had the maximum texture coefficient and SBN thin films showed a highly c-axis (001) orientation. The influences of different RTA-treated temperatures on the polarization-applied electric field (P-E) curves and the capacitance-voltage (C-V) curves were also investigated.     

Mechanical properties determined by nanoindentation tests of [Pb(Zr,Ti)O3] and [Pb(Mg1/3Nb2/3)1−xTixO3] sputtered thin films

As the introduction of piezoelectric materials into micro electromechanical systems increases, there is a correlating requirement for understanding the mechanical properties of these films. We have investigated the mechanical properties of unpoled PZT [Pb(Zr,Ti)O₃] and PMNT [Pb(Mg_1/3Nb_2/3)_1−xTi_xO₃] thin films deposited by sputtering. In this study, nano-indentation, a technique which allows determination of the transverse mechanical properties, is used. It is the easiest method for assessing the biaxial elastic modulus and the hardness of thin films. It was confirmed that neither cracks, nor pile-ups, were observed for indentation depths below 20% of the film's thickness.The continuous stiffness method was used and allowed us to demonstrate that the indentation modulus decreases continuously with increasing grain diameter. This can be explained by the orientation changes of the crystallites with increasing grain diameter. The indentation modulus measured under load, or at almost null load (that is when the ferroelectric domains are or are not oriented by the stress) are coherent with those determined by the same method with a hard bulk ceramic. These results tend to show that the compliance C_ij of the hard bulk ceramic can possibly be used with sputtered thin films. The hardness is almost independent of the grain diameter (H_b ≅ 7.5 ± 0.9 GPa) and higher than that for the bulk PZT ceramics considered in this study. PMNT and PZT films have appreciably the same mechanical characteristics. No influence of the film thickness was found on the values of both of these parameters.     

Crystallization behavior and domain structure in textured Pb(Zr0.52Ti0.48)O3 thin films by different annealing processes

Amorphous Pb(Zr_0.52Ti_0.48)O₃ (PZT) thin films were prepared on the Pt/Ti/SiO₂/Si substrates by radio-frequency magnetron sputtering at room temperature. After rapid thermal annealing (RTA) and conventional furnace annealing (CFA) at different temperatures, the films were transformed into polycrystalline PZT thin films with (111) and (100) orientation, respectively. The phase formation and ferroelectric domains correlated with different orientation were systematically investigated by X-ray diffraction and piezoresponse force microscopy. The results showed that the perovskite PZT crystal with [111] orientation hetero-nucleated preferentially on top of the PtPb intermetallic phase at the PZT/Pt interface during RTA process. It is of interest to find that the domain self-organized into a structure with rounded shape at the early stage of crystallization. While the nucleation of the films treated by CFA dominantly homo-nucleated, thus the (100) orientation grains with minimum surface energy were easy to grow. The texture effects on ferroelectric properties of PZT films were also discussed in relation to the domain structure.     

Zn^2＋掺杂的YBCO薄膜的超导性能研究

采用溶胶-凝胶法在LaAlO3（LAO）单晶衬底上制备了Zn^2＋掺杂的YBCO薄膜,用X射线衍射（XRD）、高分辨透射电子显微镜（HRTEM）以及标准四引线法分别研究了Zn^2＋掺杂的YBCO薄膜的微观结构、生长取向以及超导性能。结果表明,随Zn2＋掺杂浓度的增大薄膜的临界电流密度提高,而临界转变温度下降、临界转变温区变宽;但当掺杂量〉0.5%（摩尔分数）时,会影响YBCO的c轴取向生长,导致超导性能变差。通过优化掺杂比例后得到Zn2＋掺杂0.5%（摩尔分数）的YBCO薄膜具有最好的综合超导性能,其TC为91.3K,ΔT为1.1K,Jc约为1.54MA/cm^2（77K,0T）。     

Electron back-scattered diffraction of crystallized vanadium dioxide thin films on amorphous silicon dioxide

Crystalline films and isolated particles of vanadium dioxide (VO₂) were obtained through solid phase crystallization of amorphous vanadium oxide thin films sputtered on silicon dioxide. Electron back-scattered diffraction (EBSD) was used to study the crystals obtained in the thin films, to differentiate them from different vanadium oxide stoichiometries that may have formed during the annealing process, and to study their phase and orientation. EBSD showed that the crystallization process yielded crystalline vanadium dioxide thin films, semi-continuous thin films, and films of isolated particles, and did not show evidence of other vanadium oxide stoichiometries present. Indexing of the crystals for the orientation study was performed using EBSD patterns for the tetragonal phase of vanadium dioxide, since it was observed that EBSD patterns for the monoclinic and tetragonal phases of vanadium dioxide are not distinguishable by computer automated indexing. Using the EBSD patterns for the tetragonal phase of vanadium dioxide, orientation maps showed that all VO₂ crystals that were measurable (approximately the thickness of the film) had a preferred orientation with the c-axis of the tetragonal phase parallel to the plane of the specimen.     

Si(100)衬底上PLD法制备高取向度AlN薄膜

采用脉冲激光沉积法(PLD),以KrF准分子为脉冲激光源,Si(100)为衬底,同时引 入缓冲层TiN和Ti_0.8Al_0.2N,制备了结晶质量优异的A1N薄膜,X射线衍射(XRD)及反射 式高能电子衍射(RHEED)分析表明A1N薄膜呈(001)取向、二维层状生长.研究发现,薄膜 的生长模式依赖于缓冲层种类,直接在Si衬底上或MgO／Si衬底上的A1N薄膜呈三维岛状生 长;而同时引入缓冲层TiN和Ti_0.8Al_0.2N时,A1N薄膜呈二维层状生长.此外,激光能量密 度大小对A1N薄膜的结晶性有显著的影响,激光能量密度过大,薄膜表面粗糙,有颗粒状沉积 物生成.在氮气气氛中沉积,能使薄膜的取向由(001)改变为(100).     

MOD法制备的Bi3.25Nd0.75Ti3O12薄膜的铁电各向异性行为

采用金属有机分解法(MOD)在(111)Pt／Ti／SiO2／Si衬底上制备了含(117)成分的c轴择优取向和α轴择优取向的Bi3.25Nd0.75Ti3O12(BNT)薄膜．实验发现，BNT薄膜的品型结构主要依赖于预退火条件．电学性能测试表明，α轴择优取向的BNT薄膜具有高的剩余极化和矫顽场，较高的介电常数和介电损耗，以及较大的电容调谐率；而c轴择优取向的则相反．BNT薄膜具有同Bi4Ti3O12(BIT)薄膜相似的铁电各向异性行为．