原位聚合沉积制备聚苯胺/聚酰亚胺/聚苯胺复合膜

以聚酰亚胺(PI)膜为基体,采用分散聚合原位沉积方法制得聚苯胺/聚酰亚胺/聚苯胺(PANI/PL/PANI)三层复合膜.复合膜表面PANI层外观质量优异,电导率达10~0S/cm.实验结果表明:加入高浓度空间稳定剂(聚乙烯吡咯烷酮,PVP)、调整氧化剂(过硫酸铵,APS)和介质酸(盐酸)的用量可制得表面质量和电导率高的复合膜.较适宜的反应条件为稳定剂质量浓度4%,APS与苯胺(An)的物质的量比为2:4,盐酸浓度为0.5 mol/L.     

Preparation of a Monodispersed Suspension of Barium Titanate Nanoparticles and Electrophoretic Deposition of Thin Films

A transparent and stable monodispersed suspension of nanocrystalline barium titanate was prepared by dispersing a piece of BaTiO₃ gel into a mixed solvent of 2-methoxyethanol and acethylacetone. The results of high-resolution transmission electron microscopy (HR-TEM) and size analyzer confirmed that the BaTiO₃ nanoparticles in the suspension had an average size of ∼10 nm with a narrow size distribution. Crystal structure characterization via TEM and X-ray diffraction indicated BaTiO₃ nanocrystallites to be a perovskite cubic phase. BaTiO₃ thin films of controlled thickness from 100 nm to several micrometers were electrophoretic deposited compactly on Pt/Ti/SiO₂/Si substrates. The deposited thin film had uniform nanostructure with a very smooth surface.     

Pulsed-Laser Deposition of Barium Titanate Thin Films

Barium titanate (BaTiO₃) thin films have been deposited on single-crystal magnesia (MgO) substrates by pulsed-laser ablation. Temperature dependence of capacitance measurements show a peak of 110°C, indicative that a ferroelectric phase transition has occurred at this temperature. This value is lower than that determined for single-crystal BaTiO₃, but consistent with that found for BaTiO₃ thin films produced by other methods. It has been demonstrated that the microstructure of the films can be varied by changes in the deposition parameters. Optimizing these variations permits the formation of thin films with controlled microstructures and properties.     

Coalescence of Thin Films of Gold Condensed on Glass

Thin films of gold were deposited by evaporation onto glass surfaces generated by slow fracture in a vacuum. Such films characteristically show an agglomerated or coalesced structure. Deliberate contamination of the substrate and growing films with O₂, CO₂, H₂O, and Ar by exposure to a pressure of 0.0013 Pa (1×10⁻⁵ torr) of the gas had no effect on the structure of films of an average thickness of 5 nm (50 Å). Similar treatment of the films with N₂ resulted in a decrease in the extent of agglomeration of the gold. Treatment of the substrate with N₂ prior to the deposition caused an even greater decrease in agglomeration. Films of an average thickness of 2 nm (20 Å) were not affected detectably by the N₂ treatment. The available evidence indicated that the N₂ acted directly on the glass and that the structure of the films was unaffected by minor variations in the age of the surface or by differences in the speed of the fracture which generated the surface. The film structure was not changed by extended exposure to the atmosphere.     

Novel Spray-Pyrolysis Deposition of Cuprous Oxide Thin Films

Spray pyrolysis of aqueous solutions that include copper(II) acetate, glucose, and 2-propanol was studied for the formation of cuprous oxide (Cu₂O) thin films on glass substrates. The deposition conditions, based on the phase relations of the films, were investigated in terms of solution concentration and substrate temperature. Also, the formation process was kinetically discussed. The Cu₂O thin film obtained here was composed of rounded grains ∼50 nm in size with a surface roughness of ∼30 nm. This film was reddish yellow and showed indirect and direct bandgap energies of 1.95 and 2.60 eV, respectively. Furthermore, the film exhibited p -type conduction, with a resistivity of ∼100 Omegacm.     

自组装金纳米粒子薄膜SERS研究

采用静电自组装技术制备了金纳米粒子薄膜,研究了薄膜的表面增强拉曼散射(SERS)活性。自组装金纳米粒子薄膜具有明显的SERS效应,其中2双层薄膜的增强效应最强。金纳米粒子相互靠近但又不至于连通的状态具有最强的增强效果。若金纳米粒子通过点、面接触形成连通网络,将导致入射光激发表面等离子体波的机率下低,使增强效果降低。     

原位聚合沉积透明导电聚苯胺薄膜的研究进展

苯胺在化学氧化聚合过程中,可自发地聚合沉积在不同基体表面,形成透明导电聚苯胺薄膜。重点介绍近年来国内外在玻璃、聚合物、纤维织物和二氧化硅基体表面原位聚合沉积透明导电聚苯胺薄膜的研究进展,并探讨了反应机理。展望了透明导电聚苯胺薄膜在光电器件和微电子器件领域的应用前景。     

Hydrolysis Deposition of Thin Films of Antimony-Doped Tin Oxide

Thin films of antimony-doped tin oxide have been obtained by a new technique, the so-called hydrolysis deposition method, in which hydrolyzed solids are precipitated from metal fluoride solutions. Mixed solutions of SnF₃ and SbF₃ produce antimony- and fluorine-doped tin oxide films. The amount of antimony can be controlled in a wide range by adjusting the initial fluoride concentrations of the solution. The film containing 2.9 mol% antimony heated at 500°C has an electrical resistivity of 1.0 × 10⁻³Ω·cm, which is lower than previously obtained by wet-chemical techniques.     

沉积温度对AZO薄膜性能的影响

在采用直流磁控溅射制备AZO(Aluminum Doped Zinc Oxide,掺铝氧化锌)薄膜的过程中,AZO薄膜的光电性能取决于镀膜过程中的各种工艺参数,包括溅射气压、沉积温度、溅射功率和靶基距等。本文主要研究在固定其它工艺参数不变的情况下,通过改变沉积温度在不同的温度下分别制备AZO薄膜,利用SEM、X射线衍射仪等测试不同AZO薄膜的微观结构,并分析研究不同沉积温度下制备AZO薄膜光电性能及结构的变化特性,以筛选出制备高质量AZO膜的最佳沉积温度。     

Nanocrystalline Tin Oxide Thin Films via Liquid Flow Deposition

Nanocrystalline films of SnO₂ were deposited by liquid flow deposition (LFD), i.e., by flowing aqueous solutions of SnCl₄·5H₂O and HCl over single-crystalline silicon substrates at 80°C. The substrates were either oxidized and fully hydrolyzed (bare silicon) or oxidized, hydrolyzed, and then coated with siloxy-anchored organic self-assembled monolayers (SAMs). Continuous, adherent films formed on sulfonate- and thioacetate-functionalized SAMs; adherent but sometimes discontinuous films formed on bare silicon and methyl-functionalized SAMs. The films contained equiaxed cassiterite crystals, ∼4–10 nm in size. The film thickness increased linearly with deposition time. The maximum growth rate observed was 85 nm·h⁻¹ on sulfonate SAM, and the maximum film thickness obtained was 1 μm. A new dimensionless parameter, the normalized residence time, τ, was introduced for the purpose of interpreting the influence of solution conditions (i.e., degree of supersaturation, as controlled via pH, and tin concentration) and flow characteristics (flow rate and the configuration of the deposition chamber) on the growth rate in LFD processes. The results were consistent with a particle attachment mechanism for film growth and inconsistent with heterogeneous nucleation on the substrate.     

Low Temperature Chemical Vapor Deposition of Aluminosilicate Thin Films on Carbon Fibers

We report the deposition of aluminum oxide and aluminosilicate thin films onto carbon fiber substrates, at temperatures of 200° and 250°C, respectively. For aluminosilicate films, the Al/Si ratio of the resultant film varied concomitantly with the composition of the liquid precursor mixture. The growth rate for the oxide films was 15–17 Å/min, comparable with other methods carried out at higher temperatures. Cross-section SEM images indicate that the deposited films are conformal, following the complex topography of the carbon fiber substrate. Preliminary gas-phase IR analysis suggests that the coatings decompose the nerve agent simulant dimethyl methylphosphonate at temperatures as low as 35°C, suggesting the utility of the reported methodology for the design/fabrication of actively protective fabrics and clothing.     

Chemical Vapor Deposition of Polymer Thin Films Using Cationic Initiation

Chemical vapor deposition (CVD) is an attractive technique for the fabrication of high‐quality polymer thin films. The scheme used to initiate polymer chain growth is fundamental to controlling polymer thin film chemistry. A new initiation scheme for polymer CVD utilizing cationic initiation with a strong Lewis acid, TiCl₄, in combination with a hydrogen donor, H₂O, is presented. This coinitiation scheme results in polystyrene deposition rates of 139 nm min^?1, relative to just 34 nm min^?1 when TiCl₄ is used alone. Characterization by Fourier transform infrared spectroscopy shows that the polymer structures of polystyrene films prepared by conventional solution‐based techniques and cationic CVD are similar. Synthesis of cross‐linked polymer thin films is also demonstrated by depositing poly(divinylbenzene) and showing its insolubility in a range of solvents. The practical utility of these poly(divinylbenzene) films as corrosion resistant coatings is demonstrated. In 1 n HCl, 200 nm thick films on stainless steel increase the polarization resistance by a factor of 44 relative to bare, untreated stainless steel.     

Low Vacuum Deposition of Aluminum Nitride Thin Films by Sputtering

Conventionally, sputtering deposition of thin films requires a low base pressure (high vacuum) to minimize influences of residual gases. Here, a high base pressure (low vacuum) was used, which can reduce significantly the overall processing time. Aluminum nitride ( AlN ) was selected as a model system of dielectric nitrides. All the analyses revealed that the obtained films under a low vacuum environment within specific processing windows exhibited characteristics similar to those of high‐vacuum made AlN films. Such a low vacuum deposition technique takes advantages of kinetically favorable formation of the nitride films and hence, has great potentials in many more technological applications.     

Chemical Solution Deposition of Columnar-Grained Metallic Lanthanum Nitrate Thin Films

Columnar and (100)-oriented LaNiO₃ thin films were prepared on silicon substrates by a chemical solution deposition (CSD) process using a 0.05 M solution. By reducing the individual layer thickness to 10 nm, columnar LaNiO₃ films with a lateral grain size of ∼120 nm were obtained. The success of this approach required restricting the individual layer thickness to a value below the grain size observed for equiaxed films. This change in microstructure resulted in an improvement in conductivity. The columnar LaNiO₃ film with a thickness of 300 nm showed a resistivity of 4.5 × 10⁻⁵Ω·cm, which is lower by one order of magnitude than that of fine-grain equiaxed films that typically result from CSD methods.     

Thin Copper, Gold, and Aluminum Films on Silicate Glass

The composition and structure of thin copper, gold, and aluminum films deposited on a substrate made of vitreous quartz are investigated. The composition of the film – substrate interfaces is analyzed.     

在单壁碳纳米管上自动沉积金纳米粒子时所用润湿剂的研究

在用单壁碳纳米管直接自动沉积Au纳米粒子的时候,可以使用不同的溶剂与水混合配制氯金酸溶液,此时这些溶剂所起的作用是润湿碳管表面,从而使Au纳米粒子可以更好地沉积在碳管上。通过将Au沉积在单壁碳纳米管一系列的实验比较,最后发现,润湿碳管的溶剂不仅可用乙醇,还可以使用甲醇、丙酮、异丙醇等,其中沉积效果较好的是：50％的乙醇和30％的丙酮的水溶液。     

Mechanism of Biaxial Alignment of Oxide Thin Films during Ion-Beam-Assisted Deposition

The mechanism of biaxial alignment was examined for yttria-stabilized zirconia (YSZ) and La_1−xCa_xMnO₃ (LCMO) films that were fabricated by ion-beam-assisted deposition (IBAD). Films that were deposited with both dual-ion-beam deposition and ion-assisted electron-beam evaporation were studied. The film texture formation was mostly dependent on the ratio of ion bombardment to molecule arrival and on the angle of the incident ions with respect to the substrate. Results were not dependent on the deposition technique. The observed IBAD YSZ and IBAD LCMO biaxial alignment did not occur because of ion channeling. It has been shown that the preferred film orientation develops because of anisotropy of ion-induced damage on various crystal surfaces.     

Characterization of Lead Oxide Thin Films Produced by Chemical Vapor Deposition

As a step toward creating a chemical vapor deposition (CVD) process for PbTiO₃ thin films, lead oxide films were deposited and then examined. The reaction was oxidation controlled, with an apparent activation energy of 97 kJ/mol in this low-temperature, low-pressure metalorganic CVD (MOCVD) process. Across the deposition parameters examined, several distinct types of morphology were observed. Growth occurred as a combination of layer-on-layer and island formation. The structural and chemical properties of the lead oxide were examined by Auger electron spectroscopy, Raman spectroscopy, X-ray diffraction, scanning electron microscopy, and electron diffraction. Various forms of lead oxide were produced (litharge, massicot, and scrutinyite, singly or in combination with each other). The deposition parameters used in this work showed a tendency to maintain the same crystalline form from the initial nucleation stages through post-deposition annealing. Lead oxide formed readily on SiO₂ surfaces (contrary to studies by other researchers) and, indeed, reacted with the underlying SiO₂ layer.     

化学浴沉积法制备Sb掺杂SnS薄膜

以氯化亚锡、硫代乙酰胺、三氯化锑为反应物,采用化学浴沉积法在玻璃衬底上沉积不同锑掺杂量(摩尔分数)硫化锡(Sn S:Sb)膜,研究了锑掺杂量对薄膜晶相结构、表面形貌和光电性能的影响。结果表明:锑掺杂Sn S薄膜是具有正交结构多晶薄膜,薄膜为纳米片组装成的花状球形颗粒。随着Sb掺杂量由1.8%增加到7.2%,其相应的禁带宽度从0.93 e V增加到1.30 e V。随着Sb掺杂量的增加,Sn S薄膜的电阻率呈现先下降后增大趋势,当Sb掺杂量为3.6%时,其最小值为5.21×103?·cm。