A series of highly soluble maleimide-based polymers with photoreactive pendant group were synthesized and used as a gate dielectric insulator for organic thin film transistors. Photoalignment properties were characterized by UV-visible spectroscopy and the alignment of liquid crystals. Photopolymerization of polymer-coated organic thin film transistors with linearly polarized UV light induces anisotropy in field-effect mobility. The gate dielectric insulator based on the photoalignable maleimide shows higher field-effect mobility and on/off current ratio than those from a SiO 2 gate dielectric insulator with the values of 0.3 cm 2 V 21 s 21 and 10 4 , respectively. Our results demonstrate that the photo-induced anisotropy of alignment films to control the molecular order of semiconducting pentacene is a promising technology for improving the performance of organic thin film transistors.

Thermal and Photochemical Reactions of Benzosilacyclobutenes with Alcohols. Intermediacy of o-Silaquinone Methide in the Photochemical Reactions.-The thermal reaction of the easily obtainable benzosilacyclobutenes (V) with alcohols (VI) (12 examples) yields, in contrast to an earlier report and contrary to a similar photochemical reaction, a mixture of the silanes (VII) and (VIII). The photolysis of (V) and probably the thermolytic formation of the tolylsilanes (VII) too, proceeds via an o-silaquinone methide intermediate (IX). -(KANG, K.-T.; YOON, U. C.; SEO, H. C.; KIM, K. N.; SONG, H. Y.; LEE, J. C.; Bull. Korean Chem.

Substituent‐induced electroluminescence polymers—poly[2‐(2‐dimethyldodecylsilylphenyl)‐1,4‐phenylenevinylene] [(o‐R3Si)PhPPV], poly[2‐(3‐dimethyldodecylsilylphenyl)‐1,4‐phenylenevinylene] [(m‐R3Si)PhPPV], and poly[2‐(4‐dimethyldodecylsilylphenyl)‐1,4‐phenylenevinylene] [(p‐R3Si)PhPPV]—were synthesized according to the Gilch polymerization method. The band gap and spectroscopic data were tuned by the dimethyldodecylsilyl substituent being changed from the ortho position to the para position in the phenyl side group along the polymer backbone. The weight‐average molecular weights and polydispersities were 8.0–96 × 104 and 3.0–3.4, respectively. The maximum photoluminescence wavelengths for (o‐R3Si)PhPPV, (m‐R3Si)PhPPV, and (p‐R3Si)PhPPV appeared around 500–530 nm in the green emission region. Double‐layer light‐emitting diodes with an indium tin oxide/poly(3,4‐ethylenedioxythiophene)/polymer/Al configuration were fabricated with these polymers. The turn‐on voltages and the maximum brightness of (o‐R3Si)PhPPV, (m‐R3Si)PhPPV, and (p‐R3Si)PhPPV were 6.5–8.7 V and 1986–5895 cd/m2, respectively. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2347–2355, 2004

ABSTRACT:A new class of photoresist matrix polymers based on vinyl ether-maleic anhydride (VEMA) alternating copolymers was developed for ArF single-layer lithography. These polymers were synthesized by copolymerization of alkyl vinyl ether and maleic anhydride alternating copolymers with acrylate derivatives containing bulky alicyclic acid-labile protecting groups. The resulting polymers showed good control of polymerization and high transmittance. Also, these resists exhibited good adhesion to the substrate, high dry-etching resistance against CF 4 mixture gas (1.02 times the etching rate of deep UV resist), and high selectivity to silicon oxide etching. Using an ArF excimer laser exposure system with 0.6 NA, 120-nm L/S patterns were resolved under conventional illumination.