Poly films, patterned

Chitosan-stabilized Au NPs can be selectively synthesized on surfaces like poly (dimethylsiloxane) (PDMS) films using HAuC14 as precursor. The computation of surface plasmon bands (SPBs) based on Mie theory and experimental results indicates that the particles are partially coated by chitosan. The proposed mechanism implies that chitosan acts as a reducing/stabilizing agent. Furthermore, PDMS films patterned with chitosan could induce localized synthesis of gold nanoparticles in regions capped with chitosan only [110]. 

An array of 10- i,m microlenses was fabricated from the adhesion of an aminated silicasol on a poly[methyl(phenyl)silane-co-methyl(3,3,3-tri-fluoropropyl)silane] (CF3PMPS) film patterned by UV light irradiation.132 By soaking the UV-patterned polysilane film into the sol-gel solution, a convex xerogel layer adhered only to the UV-exposed poly silane, which was cured to form a glass that functioned as a condensing lens. 

Figure 11.12 Evolution of a bubble defect formed at (a) resist coat, (b) through development, and (c) patterning with ASML PAS5500/300 KrF stepper. Unexposed resist loss for the UTRfilm was 6-10 nm. The poly-Si patterns are 180-nm lines and spaces. Film thickness was 100 nm. ...

In another work [81] a silver thin-film pattern was covered with a polyimide protection layer with a 50 pm wide slit at the center of the pattern and the Ag AgCl layer was grown from there into the silver layer. A liquid junction was formed with a photocurable hydrophihc polymer. A silicone rubber passivation covered the entire area except for the pad and the end of the junction. The complete miniature liquid-junction reference electrode could maintain a stable level within 1 mV for time longer than 100 h with the aid of poly(vinyl pyrrolidone) matrix in the electrolyte layer. 

As an indication of the changes in deformation modes that can be produced in ionomers by increase of ion content, consider poly(styrene-co-sodium methacrylate). In ionomers of low ion content, the only observed deformation mode in strained thin films cast from tetra hydrofuran (THF), a nonpolar solvent, is localized crazing. But for ion contents near to or above the critical value of about 6 mol%, both crazing and shear deformation bands have been observed. This is demonstrated in the transmission electron microscope (TEM) scan of Fig. 3 for an ionomer of 8.2 mol% ion content. Somewhat similar deformation patterns have also been observed in a Na-SPS ionomer having an ion content of 7.5 mol%. Clearly, in both of these ionomers, the presence of a... 

Tetra(o-aminophenyl)porphyrin, H-Co-Nl TPP, can for the purpose of electrochemical polymerization be simplistically viewed as four aniline molecules with a common porphyrin substituent, and one expects that their oxidation should form a "poly(aniline)" matrix with embedded porphyrin sites. The pattern of cyclic voltammetric oxidative ECP (1) of this functionalized metal complex is shown in Fig. 2A. The growing current-potential envelope represents accumulation of a polymer film that is electroactive and conducts electrons at the potentials needed to continuously oxidize fresh monomer that diffuses in from the bulk solution. If the film were not fully electroactive at this potential, since the film is a dense membrane barrier that prevents monomer from reaching the electrode, film growth would soon cease and the electrode would become passified. This was the case for the phenolically substituted porphyrin in Fig. 1. 

Compression molded (150°C for 3 minutes press chilled with cold water immediately thereafter) samples of poly(trans-l,4-hexadiene) (14) and poly(5-methyl-l,4-hexadiene) were examined with a General Electric (XRD-3) X-ray unit. Transmission Laue X-ray photographs were taken using nickel filtered copper X-radiation. Samples were stretched to four times of their original lengths to obtain oriented fibers. The fiber patterns were obtained in a flat plate film holder with the specimen to film distance standardized at 5 centimeters. X-ray diffraction patterns were similarly obtained for the hydrogenated sample of poly(5-methyl-l,4-hexadiene). 

M Remmers, D Neher, and G Wegner, Photo-cross-linkable poly(p-phenylcnc)s. Synthesis, Langmuir-Blodgett multilayer film properties and pattern formation, Macromol. Chem. Phys., 198 2551-2561, 1997. 

In the patterning experiments, chlorinated poly(styrene) films were baked at 120 C for 15 mins, in a forced air oven, equilibrated for -12 hrs. inside the humidity-controlled glove box, exposed to deep-UV radiation and treated with TiCU under usual conditions. No significant variation in the lithographic parameters was observed by varying the relative humidity in the 30-60% range in the glove box. 

Figure 11. SEM of 0.4 pm line and space patterns in a 1.2 pm thick chlorinated poly(styrene) film exposed with 250 mJ/cm2 of 248 nm light, treated with TiCl4 and developed by O2 RIE.

A photooxidative scheme has been developed to pattern sub half-micron images in single layer resist schemes by photochemical generation of hydrophilic sites in hydrophobic polymers such as poly(styrene) and chlorinated poly(styrene) and by selective functionalization of these hydrophilic sites with TiCU followed by O2 RIE development. Sub half-micron features were resolved in 1-2 pm thick chlorinated poly(styrene) films with exposures at 248 nm on a KrF excimer laser stepper. The polymers are much more sensitive to 193 nm (sensitivity 3-32 mJ/cm2) than to 248 nm radiation (sensitivity -200 mJ/cm2) because of then-intense absorption at 193 nm. 

Scheme 3 Procedure used for preparing patterned hyperbranched poly(acrylic acid) films by /x-contact printing...

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