过渡层对含氢非晶碳膜生长的影响

本文利用射频等离子体增强化学气相沉积（RFPECVD）工艺在不锈钢基底上制备了含氢非晶碳膜（a-C：H膜）。在沉积碳膜之前，首先在基底表面预先沉积了Ti／TiC、Ti／TiN和Ti／TiN／TiC等过渡层以提高膜基结合力。利用激光Raman光谱分析了过渡层对a-C：H膜生长过程及膜中sp^3含量的影响。实验结果表明，采用Ti／TiN／TiC过渡层时所制备的a-C：H膜中sp^3含量最多，同时膜基结合力最大。     

硅衬底碳化对异质外延SiC薄膜结构的影响

用LPMOCVD方法在P—Si（111）衬底上异质外延生长SiC,用碳化方法生长出具有单晶结构的3C—SiC薄膜,研究了开始碳化温度、丙烷流量和碳化时间对结晶质量的影响．结果表明,在较低的温度开始碳化不利于丙烷的分解,不能形成很好的过渡层;碳化时丙烷流量过大会造成碳污染,碳化时间过长使过渡层的结晶质量降低．最佳的碳化条件为：开始碳化温度1150℃,碳化时间和碳化时丙烷的流量分别为8min和2sccm．     

钛酸锶钡薄膜C-V曲线不对称现象研究

采用射频（RF）磁控溅射在Pt／Ti／SiO2／Si（100）衬底上制备了Ba0.6Sr0.4TiO3（BST）薄膜。通过研究BST薄膜的电容-偏压（C-V）特性曲线发现,溅射过程中的离子注入引起底电极／铁电薄膜界面处产生了过渡层,从而导致C-V曲线不对称。最后我们通过改进溅射工艺对这一机理进行了实验验证。     

Sol-gel独立前驱单体制备PZT铁电薄膜技术

采用醋酸铅、硝酸氧锆(硝酸锆)、钛酸丁酯独立稳定的前驱单体。sol—gel法旋转涂膜技术制备了PZT铁电薄膜。研究了水的添加量对溶胶形成的影响,比较了不同的溶胶浓度、膜层结构(PT／PZT／PT Sandwich)及热处理工艺条件对薄膜结构、铁电性能的影响。     

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。     

通过制备Ti/TiC和Si/SixNy过渡层在铜基体上沉积类金刚石膜的研究

将磁控溅射物理气相沉积（MS-PVD）和电子回旋共振-微波等离子体增强化学气相沉积（ECR—PECVD）技术相结合，在铜基体上通过制备两种不同的过渡层，成功地沉积了类金刚石膜。拉曼光谱结果分析表明，所制备的碳膜都具有典型的类金刚石结构特征。通过原子力显微镜对薄膜的微观形貌进行分析，采用纳米压痕测量薄膜的硬度和模量。并对Ti／TiC过渡层和Si／SixNy过渡层上沉积的类金刚石薄膜进行了研究对比。     

沥青过渡层对C/C复合材料力学性能的影响

在2D碳／碳（C／C）复合材料的碳纤维与基体热解碳间引入中间相沥青做过渡层，研究了中间相沥青的引入对C／C复合材料力学性能的影响．结果表明，与没有过渡层，普通沥青做过渡层、中间相沥青做过渡层的三类C／C复合材料比较．采用沥青做过渡层可以提高复合材料的力学性能，采用中间相沥青做过渡层制备的C／C复合材料的弯曲强度比采用普通沥青做过渡层提高44％，剪切强度提高15％．中间相沥青的引入可以使碳纤维束间和束内的结合强度不同，从而使基体断裂产生的裂纹扩散时发生偏转，复合材料的强度和韧性同时得到提高．     

新型定向碳纳米管/炭复合材料的制备与表征

采用化学气相沉积（CVD）方法制备了厚度超过4mm的定向碳纳米管（ACNTs）阵列，并以此为骨架，利用化学气相渗（CVI）工艺制备了新型的定向碳纳米管／炭（ACNT／C）复合材料。利用SEM、PLM、XRD、TGA和Raman光谱对ACNT／C复合材料进行了表征。结果表明：ACNT／C复合材料中的热解炭主要为类粗糙层（RL）结构，而在相同工艺条件下制备的炭／炭（C／C）复合材料的热解炭为典型的光滑层（SL）结构。ACNT／C复合材料晶化程度明显优于相同工艺条件下的C／C复合材料。同时，ACNT／C复合材料在空气中的热失重转变温度比相同工艺条件下制备的C／C复合材料提高了约50℃左右。     

热诱导相分离法制备低密度聚乙烯微孔膜——（1I）动力学因素对微孔膜结构的影响

选择低密度聚乙烯（LDPE）为主体材料，二苯醚（DPE）为稀释剂，研究了淬冷温度、粗化时间等影响液滴生长的动力学因素对热诱导相分离法（TIPS）制备LDPE／DPE微孔膜结构的影响。结果表明，在相同粗化时间的条件下，随着LDPE／DPE体系冷却温度的逐渐升高，孔径逐渐变大。对于质量百分数为20％LDPE／DPE体系，在结晶温度以下（0℃、30℃、60℃）粗化时。温度对微孔膜的孔径影响较小。而在90℃的恒温条件粗化时，体系始终处在液一注相分离区域，最终得到微孔膜的孔径接近5μm。在结晶温度以下（60℃）进行恒温粗化，粗化时间对微孔膜的孔径影响不大；而在结晶温度以上（90℃）进行恒温粗化时，则是随着粗化时间的延长，微孔膜的孔径逐渐变大。     

Ni—Cr衬底上MOCVD法制备YSZ过渡层的研究

用ＭＯＣＶＤ方法在柔性金属上衬底上沉积超导膜是潜在的实用高温超导成材方法。用适当方法原位快速地制备有择优取向的防扩散过渡层是其中的关键。本文报导用有机源Ｙ（ｄｐｍ）３和Ｚｒ（ｄｐｍ）４，采用ＭＯＣＶＤ方法在Ｎｉ基合金衬底上沉积了Ｙ稳定的ＺｒＯ２立方相过渡层，厚度约０．５μｍ。文中研究了氧分压和沉积温度对ＹＳＺ结晶和择优取向的影响。结果表明，在生长压力为１３０Ｐａ时，氧分压低至２０Ｐａ，制备出（１１     

Hybrid influences of defect dipole and intrinsic inducing field on orientation of PbTiO3 thin film deposited on Indium Tin Oxide/glass substrate

(001)/(100) oriented PbTiO₃ (PT) thin film is prepared on a non single crystal Indium Tin Oxide (ITO)/glass substrate by sol-gel method. The mechanism of orientation is investigated via dopant element, dopant amount, oxygen pressure of atmosphere, different type of substrate, different thickness of substrate, different sol concentration and blocking layer. By substituting 2% Zn^2 +, or 2% Fe^3 +, or 2% Co^2 + ions in the Ti site of PT perovskite phase and heating at the oxygen-poor atmosphere, the PT thin film grown on the ITO(260 nm)/glass substrate forms well with (001)/(100) orientation. Moreover, this orientation phenomenon only appears when the solution concentration is below 0.1 mol/L. The orientation of PT which is attributed to the hybrid influences of defect dipole from the PT and the intrinsic electrostatic field from the ITO substrate is revealed. This work represents an important step toward controllable formation of oriented thin film on a non single crystal substrate.     

Highly oriented (Pb, La)TiO3 thin films prepared by sol-gel process

Highly oriented lead lanthanum titanate (PLT) thin films on MgO (100) and c-plane sapphire single-crystal substrates have been prepared using the sol-gel process. The orientation and the mechanism of the highly preferred oriented PLT films derived sol-gel process have been investigated. The sol-gel PLT films fabricated on MgO (100) and c-plane sapphire substrates grow preferentially with (100) and (111) crystallographic orientations respectively, regardless of the film thickness and La content. In addition, it is confirmed that the tetragonality of the PLT perovskite structure decreases with an increase of La content. The a-axis orientation of the sol-gel PLT film on MgO (100) substrate is controlled only by formation of the intrinsic tensile stress during the crystallization of the film.     

Preparation of high (100) oriented PST thin films deposited on PT/Tb inducing layer by rf-sputtering method

Tb doped PbTiO₃ (PT) thin films with (001)/(100) preferred orientation are prepared by sol-gel method. High (100) oriented Pb_0.4Sr_0.6(Ti_0.97Mg_0.03)O_2.97(PST) thin films are then deposited on the Tb doped PbTiO₃ inducing layer by rf-sputtering technique. The crystalline phase structure and orientation of the thin film are determined by X-ray diffraction. The dielectric properties of the thin films are measured by an Impedance Analyzer. Results show that the Tb doped PT films exhibit preferred orientation. The PST thin films deposited on substrate with and without PT inducing layer show (100) orientation and random orientation respectively. Higher (100) orientation appears in the PST thin films deposited on thinner inducing PT layer (one layer compare to more layers). A dielectric tunability of 39% is obtained in the PST thin film deposited on thinner PT inducing layer. It is a little higher than that deposited on thicker inducing layer.     

Effect of chelating agents on the preferred orientation of ZnO films by sol-gel process

The effect of chelating agents of ZnO precursor solutions on crystallization behavior was investigated. Two different additives, monoethanolamine (MEA) and diethanolamine (DEA), and crystalline Pt (111)/Si and amorphous SiN _x /Si substrates, were used for this study. ZnO film grown on SiN _x /Si from a DEA-chelated precursor solution shows a poorly oriented microstructure with weak crystallization peaks, while ZnO film grown on Pt(111)/Si shows a c-axis preferred orientation. In the case of ZnO films prepared with a MEA-chelated precursor solution, all films show a strong preferred orientation irrespective of substrate type. This result clearly demonstrates the role of the chelating agent on the crystallographic orientation and crystallization behavior of sol-gel processed ZnO films.     

Lead zirconate titanate thin films on GaAs substrates

Thin films of the piezoceramic lead zirconate titanate (PZT) of composition Pb(Zr0.53Ti0.47)O3 have been prepared on a platinized GaAs substrate system using a propanediol based sol-gel technique. A Si3N4 buffer layer was deposited onto the GaAs by plasma-enhanced chemical vapour deposition so as to minimize Ga and As diffusion during film fabrication. Rapid thermal processing (RTP) techniques were used to thermally decompose the sol-gel layer to PZT in a further effort to avoid problems of Ga and As diffusion. Adhesion between the electrode and substrate was found to improve when an intermediate Ti layer deposited between the Pt and Si3N4 was oxidized prior to depositing the Pt layer. A crystalline PZT film was produced on the Pt/TiO2/Si3N4/GaAs by firing the sol-gel coating at 350°C for 1 min and then at 650°C for 10 s using RTP. A single deposition of precursor sol resulted in a film 0.5 μm thick. Measured average values of remanant polarization and coercive field were 14 μC cm-2 and 47 kV cm-1, respectively. The polarization value is rather low, as conventionally fired films on silicon have remanent polarization values of 20–30 μC cm-2; the lower values may be due to incomplete crystallization during RTP, but a degradation of properties due to Ga-As diffusion, despite the precautions, cannot be ruled out at this stage. This revised version was published online in November 2006 with corrections to the Cover Date.     

Fabrication of dye-sensitized solar cells using Nb2O5 blocking layer made by sol-gel method

In this study, nanocrystalline Nb2O5 thin film has been prepared via sol-gel process using niobium ethoxide as a precursor. Sol-gel films using various ratios of H2O/Nb have been prepared on fluorinated tin oxide (FTO) glass substrate, and used as electron-blocking layer of dye-sensitized solar cell (DSSC). The Nb2O5 film as deposited was amorphous, but became crystalline with hexagonal phase after heat treatment at 600 degrees C. With higher H2O/Nb molar ratio, denser and more uniform Nb2O5 film surface was obtained. DSSCs with the structure of FTO/Nb2O5/TiO2/Dye/EL/Pt/FTO have been prepared, and their solar-cell performance was evaluated. By introduction of Nb2O5 sol-gel film between FTO and TiO2 layer in DSSCs, energy conversion efficiency could be improved.     

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。     

玻璃基Pt/Pb(Zr_(0.4)Ti_(0.6))O_3/ITO电容器的结构及物理性能研究

采用溶胶-凝胶方法在玻璃基ITO电极上制备了Pt/Pb(Zr0.4Ti0.6)O3(PZT)/ITO电容器.采用X射线衍射仪、铁电测试仪、分光光度计对其微观结构、电学性能及光学性能进行了测量.结果表明PZT薄膜结晶良好,具有(101)高度择优取向.铁电电容器具有良好的保持特性和抗疲劳特性,具有较大的剩余极化强度和电阻率,5V电压下的剩余极化强度和电阻率分别为41.7μC/cm2和2.5×109Ω.cm;漏电流测量结果表明电压小于0.8V时为欧姆导电机制,当电压大于0.8V时,漏电流满足肖特基发射机制.光学透射谱结果表明在短波范围内,PZT表现出强吸收作用;在长波范围内,PZT表现为强透射,最大透射率达到95%.     

Pt／n—n＋-Si电极上化学沉积铁氰化镍薄膜及其应用

在表面外延生长9μm的n型层的磷重掺杂的硅基底n—n＋一Si）结构上沉积约40nm铂（Pt）,经氩气保护673K热处理30min作为半导体电极（Pt／n—n＋-Si）。将半导体电极和铁氰化钾、硫酸镍以及硝酸钠的溶液接触,沉积出稳定的铁氰化镍（NiHCF）薄膜。复合电极与Pt电极组成光电化学电池,在零偏电压条件下,通过测量该电池的光电流可检测过氧化氢。通过循环伏安和X-光电子能谱对NiHCF薄膜进行了分析与表征。     

在聚酰亚胺衬底上低温制备超薄热敏铂膜的研究

通过在聚合物衬底上制备热敏薄膜可以实现非平、屈曲物体表面温度的实时监控和测量。利用脉冲激光沉积技术在聚酰亚胺衬底上低温（250℃左右）制备了超薄铂热敏薄膜,其室温下的电阻温度系数为1．01×10^-3／K。通过增加ZnO过渡层,可使铂薄膜的电阻温度系数增大为1．55×10^-3／K。