title: Microcrystallization of a Solution-Processable Organic Semiconductor in Capillaries for High-Performance Ambipolar Field-Effect Transistors.
abstract: We report on the use of microcrystallization in capillaries to fabricate patterned crystalline microstructures of the low-bandgap ambipolar quinoidal quaterthiophene derivative (QQT(CN)4) from a chloroform solution. Aligned needle-shaped QQT(CN)4 crystals were formed in thin film microstructures using either open- or closed- capillaries made of polydimethylsiloxane (PDMS). Their charge transport properties were evaluated in a bottom-gate top-contact transistor configuration. Hole and electron mobilities were found to be as high as 0.17 and 0.083 cm(2) V(-1) s(-1), respectively, approaching the values previously obtained in individual QQT(CN)4 single crystal microneedles. It was possible to control the size of the needle crystals and the microline arrays by adjusting the structure of the PDMS mold and the concentration of QQT(CN)4 solution. These results demonstrate that the microcrystallization in capillaries technique can be used to simultaneously pattern organic needle single crystals and control the microcrystallization processes. Such a simple and versatile method should be promising for the future development of high-performance organic electronic devices.
authors.affiliation: Department of Applied Chemistry and Biochemistry, Kumamoto University , Kumamoto 860-8555, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Watanabe
authors.affiliation: Department of Materials Science and Technology, Tokyo University of Science , Tokyo 162-0825, Japan.
authors.forename: Takuma
authors.initials: T
authors.lastname: Fujita
authors.forename: Jean-Charles
authors.initials: JC
authors.lastname: Ribierre
authors.affiliation: Graduate School of Natural Science and Technology, Okayama University , Okayama 700-0082 Japan.|Elements Chemistry Laboratory, RIKEN , Saitama 351-0198, Japan.
authors.forename: Kazuto
authors.initials: K
authors.lastname: Takaishi
authors.affiliation: Elements Chemistry Laboratory, RIKEN , Saitama 351-0198, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Muto
authors.forename: Chihaya
authors.initials: C
authors.lastname: Adachi
authors.affiliation: Elements Chemistry Laboratory, RIKEN , Saitama 351-0198, Japan.|Graduate School of Pharmaceutical Sciences, The University of Tokyo , Tokyo 113-0033, Japan.
authors.forename: Masanobu
authors.initials: M
authors.lastname: Uchiyama
authors.affiliation: Elements Chemistry Laboratory, RIKEN , Saitama 351-0198, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Aoyama
authors.affiliation: Department of Materials Science and Technology, Tokyo University of Science , Tokyo 162-0825, Japan.
authors.forename: Mutsuyoshi
authors.initials: M
authors.lastname: Matsumoto
keywords: ambipolar organic semiconductor; microcrystallization in capillaries; organic field effect transistor; single crystal; wet process