Langmuir films of polycyclic molecules on mercury

Langmuir films (LFs) of biphenyl and anthracene derivatives on the surface of liquid mercury were studied by surface-specific X-ray and surface tension measurements. Phases of lying-down, side-lying and standing-up molecules were found, some of which exhibit long-range lateral order. The molecular symmetry and the position and nature of the side-, end-, and headgroups are shown to dominate the structural evolution of the LFs with surface coverage.     

源气体流量比对F-DLC薄膜结构的影响

以高纯石墨作靶，CHF3/Ar作源气体采用反应磁控溅射法制备出了氟化类金刚石（F-DLC）薄膜。拉曼光谱表明，CHF3相对流量的增加会引起薄膜的D峰与G峰强度之比I（D）/I（G）减小，晶粒增大，芳香环结构出例下降。红外吸收光谱分析证实了这些推论，指出这是由于薄膜中氟含量上升的结果。     

光学薄膜在光通信中的应用

主要介绍了光学薄膜在光通信的无源型器件中的原理及应用,并与光纤光栅和平面光波导型的无源器件作简单比较。     

锆酸铅薄膜的生长特性与表面化学态

以醋酸铅和异丙醇锆为原料，乙二醇甲醚为溶剂。通过溶胶-凝胶法和快速退火工艺在Pt(111)／Ti／SiO2／Si(100)基片成功地制备出不开裂的钙钛矿PbZrO3薄膜。用XRD和原子力显微镜测量了薄膜随退火温度变化的结构和表面形貌特征，用XPS测试了650℃退火PbZrO3薄膜的表面化学态。     

Chemical compositions and optical properties of HfOxNy thin films at different substrate temperatures

High-k HfO_xN_y thin films have been grown by radio frequency (rf) reactive sputtering of metal Hf target in N₂/Ar/O₂ ambient at different substrate temperatures. The chemical compositions of the films have been investigated as a function of substrate temperature by X-ray photoelectron spectroscopy (XPS). XPS measurements showed that nitrogen concentration increases with an increase in substrate temperature. Room-temperature spectroscopic ellipsometry (SE) with photon energy 0.75–6.5 eV was used to investigate the optical properties of the films. SE results demonstrated that refractive index n increases with an increase in substrate temperature. Based on TL parameters which were obtained from the best fit results used in a simulation of the measured spectra, meanwhile, we conclude that the energy band gap (E_g) decreases with an increase in substrate temperature.     

Towards General Guidelines for Aligned,Nanoscale Assemblies of Hairy‐Rod Polyfluorene

This account highlights recent progress towards understanding the complex hierarchical levels of solid‐state structure in a prototypical helical hairy‐rod polyfluorene, poly[9,9‐bis(2‐ethylhexyl)fluorene‐2,7‐diyl] (or PF2/6). This branched‐side‐chain containing polyfluorene undergoes a systematic intermolecular self‐assembly and liquid‐crystalline phase behavior in combination with uniaxial and biaxial alignment. The latter processes yield full three‐dimensional orientation of the crystallites and polymer chains. Also reviewed are the impact of the molecular structure and phase behavior on surface morphology, anisotropic film formation, and, ultimately, the overall impact of these physical attributes on optical constants. This particular polyfluorene also represents a model system for demonstrating the applicability of mean‐field theory in detailing the self‐organization of aligned hairy‐rod block‐copolymer systems. These results of PF2/6 are compared to those of other archetypical π‐conjugated hairy‐rod polymers. General guidelines of how molecular weight influences nanostructure, phase behavior, alignment, and surface morphology are given.     

Formation of ordered microporous films with water as templates from poly(D,L‐lactic‐co‐glycolic acid) solution

Recently a method that uses water droplets at the air–solution interface as an ordered template was reported for the preparation of ordered micrometer‐size honeycomb structures. Here we show that the method can also be used for formation of honeycomb‐like porous films from random copolymers with certain hydrophilicity, besides those polymers with defined structures such as block copolymers, starlike homopolymers, amd amphiphilic polymers. This demonstrates that the stabilization of water droplets is the key factor for the regular structure. Also we indicate that size and structure of the films can be regulated by such variables as concentration and atmospheric humidity. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1846–1850, 2003     

LaNiO3薄膜热稳定性的研究

LaNiO3导电金属氧化物薄膜在现代应用科学研究中作为电极和过渡阻挡层倍受青睐，它具有很好的导电特性和稳定性。该文采用射频溅射法制备了具有(100)择优取向的赝立方结构LaNiO3-x薄膜，并进行了原位热处理。实验结果表明，在265℃的处理条件下，LaNiO3薄膜表现出不稳定性，晶格中的氧在2h内失去了2.7％。氧的损失对品格结构没有明显影响，但薄膜的导电性能明显下降，折射率和消光系数也具有相同幅度的下降。对薄膜的应用具有一定的影响。该文从LaNiO3薄膜的导电机理方面对实验现象给出了分析和解释。