title: 3D Hollow Framework Silver Nanowire Electrodes for High-Performance Bottom-Contact Organic Transistors.
abstract: We successfully fabricated high performance bottom-contact organic field-effect transistors (OFETs) using silver nanowire (AgNW) network electrodes by spray deposition. The synthesized AgNWs have the dimensions of 40-80 nm in diameter and 30-80 μm in length and are randomly distributed and interconnected to form a 3D hollow framework. The AgNWs networks, deposited by spray coating, yield an average optical transmittance of up to 88% and a sheet resistance as low as 10 ohm/sq. For using AgNWs as source/drain electrodes of OFETs with a bottom-contact configuration, the large contact resistance at the AgNWs/organic channel remains a critical issue for charge injection. To enhance charge injection, we fabricate semiconductor crystals on the AgNW using an adsorbed residual poly(N-vinylpyrrolidone) layer. The resulting bottom-contact OFETs exhibit high mobility up to 1.02 cm(2)/(V s) and are similar to that of the top-contact Au electrodes OFETs with low contact resistance. A morphological study shows that the pentacene crystals coalesced to form continuous morphology on the nanowires and are highly interconnected with those on the channel. These features contribute to efficient charge injection and encourage the improvement of the bottom-contact device performance. Furthermore, the large contact area of individual AgNWs spreading out to the channel at the edge of the electrode also improves device performance.
authors.affiliation: †POSTECH Organic Electronics Laboratory, Department of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyungbuk 790-784, Korea.
authors.forename: Jiye
authors.initials: J
authors.lastname: Kim
authors.affiliation: §School of Materials Science and Engineering, Yeungnam University, 280 Daehak-Ro, Gyungsan, Gyeongbuk 712-749, Korea.
authors.forename: So Hee
authors.initials: SH
authors.lastname: Lee
authors.affiliation: §School of Materials Science and Engineering, Yeungnam University, 280 Daehak-Ro, Gyungsan, Gyeongbuk 712-749, Korea.
authors.forename: Haekyoung
authors.initials: H
authors.lastname: Kim
authors.affiliation: ‡Department of Nano, Medical and Polymer Materials, Yeungnam University, 280 Daehak-Ro, Gyungsan, Gyeongbuk 712-749, Korea.
authors.forename: Se Hyun
authors.initials: SH
authors.lastname: Kim
authors.affiliation: †POSTECH Organic Electronics Laboratory, Department of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyungbuk 790-784, Korea.
authors.forename: Chan Eon
authors.initials: CE
authors.lastname: Park
keywords: bottom contact source/drain electrode; organic field-effect transistor; pentacene; silver nanowire; spray coating