title: Simple push coating of polymer thin-film transistors.
abstract: Solution processibility is a unique advantage of organic semiconductors, permitting the low-cost production of flexible electronics under ambient conditions. However, the solution affinity to substrate surfaces remains a serious dilemma; liquid manipulation is more difficult on highly hydrophobic surfaces, but the use of such surfaces is indispensable for improving device characteristics. Here we demonstrate a simple technique, which we call 'push coating', to produce uniform large-area semiconducting polymer films over a hydrophobic surface with eliminating material loss. We utilize a poly(dimethylsiloxane)-based trilayer stamp whose conformal contact with the substrate enables capillarity-induced wetting of the surface. Films are formed through solvent sorption and retention in the stamp, allowing the stamp to be peeled perfectly from the film. The planar film formation on hydrophobic surfaces also enables subsequent fine film patterning. The technique improves the crystallinity and field-effect mobility of stamped semiconductor films, constituting a major step towards flexible electronics production.
authors.affiliation: National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 4 and 5, Tsukuba 305-8562, Japan.
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Ikawa
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Yamada
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Matsui
authors.forename: Hiromi
authors.initials: H
authors.lastname: Minemawari
authors.forename: Jun'ya
authors.initials: J
authors.lastname: Tsutsumi
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Horii
authors.forename: Masayuki
authors.initials: M
authors.lastname: Chikamatsu
authors.forename: Reiko
authors.initials: R
authors.lastname: Azumi
authors.forename: Reiji
authors.initials: R
authors.lastname: Kumai
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Hasegawa