Solution-based metal electrode modification for improved charge injection in polymer field-effect transistors

被引：22
作者：
Frisch, J. [1 ]
Glowatzki, H. [1 ]
Janietz, S. [2 ]
Koch, N. [1 ]
机构：
[1] Univ Humberside, Inst Phys, D-12489 Berlin, Germany
[2] Fraunhofer Inst Angew Polymerforsch, D-14476 Golm, Germany
来源：
ORGANIC ELECTRONICS | 2009年 / 10卷 / 08期
关键词：
Organic electronics; Field-effect transistors; Electrodes; Interfaces; Work function; THIN-FILM TRANSISTORS; CONJUGATED POLYMERS;
D O I：
10.1016/j.orgel.2009.08.008
中图分类号：
T [工业技术];
学科分类号：
08 ;
摘要：
We report that solution-based treatment of Cu electrodes with strong electron acceptor molecules significantly decreases the contact resistance towards organic semiconductors, which is advantageous for applications such as organic field-effect transistors (OFETs). Spin-coating solutions of tetracyanoquinodimethane (TCNQ) or tetrafluoro-tetracyanoquinodimethane (F4-TCNQ) onto Cu electrodes results in strongly chemisorbed acceptor (sub)monolayers, which increase the electrode work function from 4.5 eV (bare Cu) up to 5.2 eV (F4-TCNQ-treated) even in air, as evidenced by X-ray photoelectron spectroscopy and photoelectron yield spectroscopy. The use of such modified electrodes in flexible OFETs with poly(3-hexylthiophene)-dithienyltetrafluorobenzene (P3HT-TFT) as semiconductor lead to a twofold increase of the on-current in the saturation regime and a decrease of the threshold voltage from -20 V (bare Cu) to -7 V (F4-TCNQ-treated). These results confirm that this simple solution-based process is viable for lowering organic/metal contact resistances in organic electronic devices. (C) 2009 Elsevier B.V. All rights reserved.
引用
收藏
页码：1459 / 1465
页数：7
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