Poly spin-casting

Figure Bl.19.30. Height and friction images of a spin-cast polystyrene-poly(methyl methacrylate) blend obtained with (a) gold and (b) silica probes under perfluorodecalin. Note the reversal of frictional contrast and the high spatial resolution. (Taken from [142], figure 7.)...

FIGURE 20.10 (a,b) Phase images of cryo-ultramicrotomed surfaces of triblock copolymer styrene and ethylene-butylene (SEES) samples of neat material and loaded with oil (40 wt%), respectively. (c,d) Phase images of film of triblock copolymer poly(methyl methacrylate-polyisobutylene-poly(methyl methacrylate) (PMMA-PIB-PMMA) immediately after spin-casting and after 3 h annealing at 100°C, respectively. Inserts in the top left and right comers of the images show power spectra with the value stmctural parameter of microphase separation. 

A unique methodology for the generation of nanoporous thin films using supercritical carbon dioxide (SCCO2) for potential nanolithographic applications was introduced in 2004 by Li et al. [53]. In this work, thin films of PS-poly(perfluorooctylethyl methacrylate) [PFMA] were spin-cast onto sili-... 

A. Satrijo, T. M. Swager, Facile Control of Chiral Packing in Poly(p-phenylene-vinylene) Spin-cast Films, Macromolecules, 2005, 38, 4054-4057. 

Nonconjugated poly[l,3-propanedioxy-l,4-phenylene-l,2-ethenylene(2,5-bis(tri-methylsilyl)-l,4-phenylene)- l,2-ethenylene-l,4-phenylene] (DSiPV) and conjugated MEH-PPV polymers are mixed by changing their weight ratios in 1,2-dichloroethane. The films of the blend polymers could be spin-cast from 1,2-dichloroethane solution with excellent reproducibility. AFM (atomic force microscopy) and SEM images show no indication of phase separation or layer formation due to the immiscibility of two polymers. The structures of DSiPV and MEH-PPV are shown in Fig. 24. 

TABLE 1. Effect of poly[5,5 -bis(3-dodecyl-2-thienyl)-2,2 -dithiophene] of varying molecnlar weights of the cnrrent invention on mobility and cnrrent on/off ratio when spin casted onto thin film transistor devices. 

Acridine and diphenyl butadiene were obtained from Aldrich poly (methylmethacrylate)(PMMA) from KTI Chemicals (as a 9 wt.% solution in chlorobenzene). Solutions for spin-casting were prepared as follows 1 ml of IM acridine (in 2-ethoxy ethyl acetate) in 9 ml of 9 wt.% PMMA (thus 16 wt.% acridine in film) 0.3 g diphenyl butadiene in 7 ml of 9% PMMA solution (thus 30 wt.% diphenyl butadiene)... 

Films were prepared by spin-casting at 3000 rpm for 30 sec. on fused silica substrates (similar dimensions to conventional 3 inch diameter silicon wafers) the films were not baked. Films of poly [2-(9- acridyl)ethyl methacrylate-co-methyl methacrylate] (herein... 

Recently, Bayer [63,64] commercialized poly(ethylenedioxythiophene)-poly-styrene sulfonate (PEDT-PSS), under the trade name TP AI4071. The PEDT-PSS is prepared as a stable dispersion in water. Films of PEDT-PSS are semi-transparent and can be spin-cast with a surface resistance of approximately 500 D/square and with 75% transmission. 

Several polymer/polyelectrolyte-nanocrystal hybrid devices have been fabricated seeking to exploit the electro and photoluminescent properties of such material [179-188]. Device fabrication in all these cases is by low-cost self-assembly based techniques. These devices utilize thin films of these hybrids obtained either by multilayer deposition or drop/spin casting methods. Thus, solar cells have been made from poly(2-hexylthiophene)-CdSe nanorod multilayers, lasers from drop cast films of CdSe-titania composites and an infrared emitter from multilayers... 

For single-layer devices, the emitting layer was spin-cast at 1000-2000 rpm from solutions in formic acid [for polypyridine (PPy) and poly (pyridylvinylene) (PPyV)] or xylenes [(for copolymers of pyridylvinylene (PyV) and phenylenevinylene... 

Figure 18. (Left) SFM images of poly(r -butylacrylate) brushes with varying degree of polymerization, n, of the polyfn-butylacrylate) side chains on mica (spin cast samples). (Right) Persistence length of a molecular brush as a function of the side chain length n. The continuous line describes the power function lp

Poly(arylene vinyene)s (PAVs) represent the most widely studied group of electroluminescent polymers. The parent compound poly(para-phenylene vinylene) (PPV, 1, Fig. 6.1) [5] is insoluble and so must be processed as a precursor polymer but derivatives such as MEH-PPV (2) [6] with solubilizing alkyl, aryl, silyl, or al-koxy chains show good solubility in organic solvents and so can be readily processed by techniques such as spin casting. By appropriate choice of substituents... 

As mentioned earlier, the COMA positive resists tend to have higher optical absorption at 193 nm than polymethacrylate and COBRA systems, which would produce a tapered image profile. To overcome this potential problem, the T-top formation by absorption of base into the top layer (see above) has been intentionally incorporated in the lithographic process (amine gradient process) [281]. Poly(acrylic acid-co-methyl acrylate) and L-proline were dissolved in water and spin-cast on a COMA resist. During PEB the amine in the overcoat diffuses into the COMA resist layer and compensates for the acid gradient caused by illumination, providing a vertical profile. 

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