Issue 36, 2014

Functionalized benzothieno[3,2 b]thiophenes (BTTs) for high performance organic thin-film transistors (OTFTs)

Abstract

New benzothieno[3,2-b]thiophene (BTT) derivatives, end-functionalized with biphenyl (Bp-BTT), naphthalenyl (Np-BTT), and benzothieno[3,2-b]thiophenyl (BBTT; dimer of BTT) moieties, were synthesized and characterized for bottom-gate/top-contact organic thin-film transistors (OTFTs). All three materials exhibit good environmental stability as assessed by thermogravimetric analysis, and no decomposition after extended light exposure, due to their wide band gaps and low-lying HOMOs. The single crystal structures of Bp-BTT and BBTT reveal flat molecular geometries, close π–π stacking, and short sulfur-to-sulfur distances, suggesting an ideal arrangement for charge transport. X-ray diffraction (XRD) measurements verify that the bulk crystal structures are preserved in the polycrystalline thin films. As a consequence, Bp-BTT and BBTT exhibit good OTFT performance, with µ = 0.34 cm2 V−1 s−1 (max) and Ion/Ioff = (3.3 ± 1.6) × 108 for Bp-BTT, and µ = 0.12 cm2 V−1 s−1 (max) and Ion/Ioff = (2.4 ± 0.9) × 107 for BBTT; whereas Np-BTT gives lower device performance with µ = 0.055 cm2 V−1 s−1 (max) and Ion/Ioff = (6.7 ± 3.4) × 108. In addition, octadecyltrichlorosilane (OTS) self-assembled monolayer (SAM) treatment of the SiO2 gate dielectric is found to be effective in enhancing the OTFT performance for all three BTT derivatives, by improving the interfacial semiconductor film morphology and in-plane crystallinity.

Graphical abstract: Functionalized benzothieno[3,2 b]thiophenes (BTTs) for high performance organic thin-film transistors (OTFTs)

Supplementary files

Article information

Article type
Paper
Submitted
28 May 2014
Accepted
25 Jun 2014
First published
06 Aug 2014

J. Mater. Chem. C, 2014,2, 7599-7607

Functionalized benzothieno[3,2 b]thiophenes (BTTs) for high performance organic thin-film transistors (OTFTs)

J. Youn, P. Huang, S. Zhang, C. Liu, S. Vegiraju, K. Prabakaran, C. Stern, C. Kim, M. Chen, A. Facchetti and T. J. Marks, J. Mater. Chem. C, 2014, 2, 7599 DOI: 10.1039/C4TC01115E

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements