Film Formation: Uniform films occupying~5 cm 5 cm were prepared by depositing 1000 lL of solution on a glass substrate. The solution was confined by inert sidewalls and allowed to dry. Films with thicknesses ranging from 1±3 lm were fabricated. Atomic force microscopy revealed a surface roughness of 4 nm over a 1 lm 1 lm region. The films exhibited interference fringes apparent in the absorption spectrum. Fabry±Perot fringe spacing indicated a phase index of 1.69 ± 0.03 between 1200 and 1500 nm. The films formed the core of planar waveguides on silica (refractive index~1.5), in which light is well-confined to the DNA±PbS material.TEM and EFTEM: TEM images were acquired using the transmitted-and scattered-electron detectors of a HD-2000 scanning transmission electron microscope operating at 200 kV (Hitachi). EFTEM imaging was performed with a Tecnai 20 (FEI, Eindhoven) transmission electron microscope equipped with an electron imaging spectrometer (Gatan, Pleasanton, CA) operated at 200 kV. Phosphorusenhanced images were collected at 155 eV energy loss, just beyond the L II,III phosphorus ionization edge. A 20 eV energy window was used. Bright-field images were collected at zero loss. For EFTEM sample preparation, carbon films 3±5 nm in thickness were floated onto 1000-mesh grids. The DNA±PbS solution was diluted in a mixture of Hepes (10 mM, pH 8) and MgCl 2 (1 mM). A small drop was placed onto the grid and allowed to adsorb to the film for 5 min. The grid was then rinsed three times with filtered distilled water and allowed to dry in air.

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ABSTRACT:In this paper, we describe a technique to prepare a copper layer on polyimide film using a polymer nanosheet as a nano-adhesion. We employ two kinds of functional polymer nanosheets: one works as an adhesion layer and the other works as a template layer to adsorb gold nanoparticles, which works as a catalyst for the electroless plating. The photoreactive polymer nanosheet was used to increase the adhesion force between the copper layer and polyimide. Furthermore, the cationic polymer nanosheets were used to adsorb a gold catalyst for electroless copper plating. Applying the technique, electroless plated copper was attached strongly onto polyimide film. Micrometer copper lines were fabricated by photopatterning the polymer nanosheets. The process using polymer nanosheets as an adhesive required no surface modification of polyimide substrate and enabled microscale copper line fabrication without discharging harmful waste. Consequently, the technique is useful for next-generation flexible printed board fabrication.

ABSTRACT:The monolayer behavior of poly(N-1H,1H-pentadecafluorooctylmethacrylamide (pC7F15MAA) spread on the air-water interface was investigated by measurement of surface pressure-area isotherm at different subphase temperatures. The monolayer of pC7F15MAA was transferred onto solid substrates as Y-type Langmuir-Blodgett (LB) film and the monolayer thickness was calculated by X-Ray diffraction techniques and surface plasmon measurements. Wettability and the surface structure of the LB film were investigated by measuring the static contact angle (cos θ) of water on the surface. The wettability varied slightly with increasing temperature. The critical surface tension measurement suggests that the surface of pC7F15MAA LB film covered mainly with CF 3 groups.KEY WORDS Langmuir-Blodgett Film / Fluorinated Polymer / Surface Plasmon Resonance / Wettability / The Langmuir-Blodgett (LB) technique is an excellent method for preparation of ultrathin films with controlled thickness at a molecular size and well-defined molecular orientation. 1 Recently, polymeric LB films have received much attention due to their superior mechanical and thermal stability than those of low molecular weight LB films 2 and the applications especially in the fields of coatings, optics, and electronics have been discussed. 3,4 The simplest method to fabricate the polymeric LB film is by deposition of preformed polymer monolayers. [5][6][7] For the fabrication of polymeric LB films, comb-like polymers with well-defined hydrophilic groups and hydrophobic hydrocarbon side chains are mostly studied. [8][9][10][11][12][13][14] Monolayer formation and LB film preparation in these polymers are determined by the balance of hydrophilic and hydrophobic interactions.Langmuir-Blodgett films of comb-like polymers with fluorocarbon side chains are attracting much recent attention due to their characteristic properties such as low friction, excellent insulation, excellent durability, and so on. 15,16 The fluorocarbon chains are also hydrophobic and have rigid character (stiffness of the C-F bond), which are suitable factors for stable monolayer formation. However, the deposition of the monolayer on solid substrates is difficult because of the weak interactions among the monolayer due to the low surface energy of fluorinated materials. Nonetheless, a few papers have been reported about monolayers and the fabrication of LB films from comb-like polymers with fluorocarbon side chains. [17][18][19][20][21] In previous works, we have found that polyacrylamide struc- ture is suitable for stable LB film formation due to the self-assembly property based on hydrogen bonding of amide group. 14,22,23 Using this excellent property of the acrylamide backbone, we have demonstrated that poly(N-fluoroalkylacrylamide)s form stable monolayers at the air-water interface and fairly uniform polymer LB films can be easily prepared. 24 In this work, we investigated the spreading behavior of poly(N-1H,1H-pentadecafluorooctylmethacrylamide) (Figure 1) on the water surface to prepare st...

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