title: Ambipolar Small-Molecule:Polymer Blend Semiconductors for Solution-Processable Organic Field-Effect Transistors.
abstract: We report on the fabrication of an organic thin-film semiconductor formed using a blend solution of soluble ambipolar small molecules and an insulating polymer binder that exhibits vertical phase separation and uniform film formation. The semiconductor thin films are produced in a single step from a mixture containing a small molecular semiconductor, namely, quinoidal biselenophene (QBS), and a binder polymer, namely, poly(2-vinylnaphthalene) (PVN). Organic field-effect transistors (OFETs) based on QBS/PVN blend semiconductor are then assembled using top-gate/bottom-contact device configuration, which achieve almost four times higher mobility than the neat QBS semiconductor. Depth profile via secondary ion mass spectrometry and atomic force microscopy images indicate that the QBS domains in the films made from the blend are evenly distributed with a smooth morphology at the bottom of the PVN layer. Bias stress test and variable-temperature measurements on QBS-based OFETs reveal that the QBS/PVN blend semiconductor remarkably reduces the number of trap sites at the gate dielectric/semiconductor interface and the activation energy in the transistor channel. This work provides a one-step solution processing technique, which makes use of soluble ambipolar small molecules to form a thin-film semiconductor for application in high-performance OFETs.
authors.affiliation: Research Institute for Solar and Sustainable energies (RISE), Heeger Center for Advanced Materials (HCAM), School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST) , Gwangju 500-712, Republic of Korea.
authors.forename: Minji
authors.initials: M
authors.lastname: Kang
authors.affiliation: Research Institute for Solar and Sustainable energies (RISE), Heeger Center for Advanced Materials (HCAM), School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST) , Gwangju 500-712, Republic of Korea.
authors.forename: Hansu
authors.initials: H
authors.lastname: Hwang
authors.affiliation: Department of Energy and Materials Engineering, Dongguk University , 30 Pildong-ro, 1-gil, Jung-gu, Seoul 04620, Republic of Korea.
authors.forename: Won-Tae
authors.initials: WT
authors.lastname: Park
authors.affiliation: Department of Physics, Blackett Laboratory, Imperial College London , London SW7 2AZ, United Kingdom.
authors.forename: Dongyoon
authors.initials: D
authors.lastname: Khim
authors.affiliation: Research Institute for Solar and Sustainable energies (RISE), Heeger Center for Advanced Materials (HCAM), School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST) , Gwangju 500-712, Republic of Korea.
authors.forename: Jun-Seok
authors.initials: JS
authors.lastname: Yeo
authors.affiliation: Research Institute for Solar and Sustainable energies (RISE), Heeger Center for Advanced Materials (HCAM), School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST) , Gwangju 500-712, Republic of Korea.
authors.forename: Yunseul
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Research Institute for Solar and Sustainable energies (RISE), Heeger Center for Advanced Materials (HCAM), School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST) , Gwangju 500-712, Republic of Korea.
authors.forename: Yeon-Ju
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Department of Energy and Materials Engineering, Dongguk University , 30 Pildong-ro, 1-gil, Jung-gu, Seoul 04620, Republic of Korea.
authors.forename: Yong-Young
authors.identifier: http://orcid.org/0000-0001-7222-2401
authors.initials: YY
authors.lastname: Noh
authors.affiliation: Research Institute for Solar and Sustainable energies (RISE), Heeger Center for Advanced Materials (HCAM), School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST) , Gwangju 500-712, Republic of Korea.
authors.forename: Dong-Yu
authors.identifier: http://orcid.org/0000-0003-2874-0329
authors.initials: DY
authors.lastname: Kim
keywords: ambipolar semiconductors; blend organic semiconductors; organic field-effect transistors; quinoids; small molecule; vertical phase separation