title: Intense pulsed light induced crystallization of a liquid-crystalline polymer semiconductor for efficient production of flexible thin-film transistors.
abstract: Here we demonstrated the split-second crystallization of a liquid-crystalline conjugated polymer semiconductor induced by irradiation with intense pulsed white light (IPWL) for the efficient improvement of electrical properties of flexible thin film transistors. A few seconds of IPWL irradiation of poly(didodecylquaterthiophene-alt-didodecylbithiazole) (PQTBTz-C12) thin films generated heat energy through the photo-thermal effect, leading to the crystallization of PQTBTz-C12 and formation of nodule-like nanostructures. The IPWL-induced crystallization of PQTBTz-C12 resulted in a threefold improvement in the field-effect mobility of thin film transistors compared to as-prepared devices. The conformational change of the PQTBTz-C12 chains was found to be strongly related to the irradiation fluence. As a proof-of-concept, the IPWL treatment was successfully applied to the PQTBTz-C12 layer in flexible transistors based on plastic substrates. The performance of these flexible devices was significantly improved after only 0.6 s of IPWL treatment, without deformation of the plastic substrate.
authors.affiliation: Photo-electronic Hybrids Research Center, Korea Institute of Science and Technology, 02792 Seoul, Korea and Department of Electronics and Computer Engineering, Hanyang University, 04763 Seoul, Korea.
authors.forename: Hee Yeon
authors.initials: HY
authors.lastname: Yang
authors.affiliation: Department of Organic Materials and Fiber Engineering, Soongsil University, 06978 Seoul, Korea.
authors.forename: Han-Wool
authors.initials: HW
authors.lastname: Park
authors.affiliation: Center for Opto-Electronic Materials and Devices, Korea Institute of Science and Technology, 02792 Seoul, Korea. jalim@kist.re.kr.
authors.forename: Soo Jin
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Photo-electronic Hybrids Research Center, Korea Institute of Science and Technology, 02792 Seoul, Korea.
authors.forename: Jae-Min
authors.initials: JM
authors.lastname: Hong
authors.affiliation: Department of Electronics and Computer Engineering, Hanyang University, 04763 Seoul, Korea.
authors.forename: Tae Whan
authors.initials: TW
authors.lastname: Kim
authors.affiliation: Department of Organic Materials and Fiber Engineering, Soongsil University, 06978 Seoul, Korea.
authors.forename: Do Hwan
authors.initials: DH
authors.lastname: Kim
authors.affiliation: Center for Opto-Electronic Materials and Devices, Korea Institute of Science and Technology, 02792 Seoul, Korea. jalim@kist.re.kr.
authors.forename: Jung Ah
authors.initials: JA
authors.lastname: Lim