Selectively patterned highly conductive poly(3,4-ethylenedioxythiophene)-tosylate electrodes for high performance organic field-effect transistors

Abstract

We have improved the performance of pentacene field-effect transistors by using highly conductive poly(3,4-ethylenedioxythiophene)-tosylate (PEDOT-Tos) source-drain electrodes (∼103 S/cm) formed by a simple solution-based process. A high field-effect mobility of 0.25 cm2/Vs and an ON/OFF current ratio of 107 were obtained in pentacene-based bottom contact organic field-effect transistors (OFETs), which constitutes an improvement over OFETs based on Au and PEDOT:PSS electrodes. Two-dimensional grazing incidence x-ray diffraction and ultraviolet photoemission spectroscopy results confirmed that the crystalline properties of the pentacene film and the hole injection from the PEDOT-Tos electrode to the pentacene layer are more efficient than those from Au and PEDOT:PSS electrodes.

Wafer‐Scale Patterning of Reduced Graphene Oxide Electrodes by Transfer‐and‐Reverse Stamping for High Performance OFETs

“…Overall, we conclude that the rGO electrodes that were patterned by TARS are applicable to various types of common organic semiconductors and yield superior device performance compared to those based on conventional metal electrodes. The electrical performance of our device is also comparable to those with organic patterned electrodes 10–12, 15–17…”

“…This value is higher than that of Al electrodes (4.28 eV)53 and thus one would expect that electron injection barrier and contact resistance is higher for rGO electrodes than Al electrodes. Analogously, one would expect that hole injection barrier and resulting contact resistance is higher for rGO electrodes than Au electrodes, because the work function for rGO is lower than that of Au (5.01 eV) 12. However, the transistor measurement, as shown above, resulted in the opposite results to the expectation based on work function argument.…”

“…Regarding these issues, various solution‐processable electrode materials have been investigated 6–9. For example, numerous research groups demonstrated OFETs based on poly(3,4‐ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) electrodes with their electrical performance comparable to those based on common metal electrodes 10–12. However, the conductivity of PEDOT:PSS is low and sensitive to moisture, prohibit its practical applications.…”

The Investigation of the Seebeck Effect of the Poly(3,4-Ethylenedioxythiophene)-Tosylate with the Various Concentrations of an Oxidant

“…We investigated the relationship between the thermopower and the electrical conductivity as a function of the concentration of the oxidant of PEDOT with a tosylate counter-ion (PEDOT-Tos). The synthesis of PEDOT-Tos was performed by the oxidation polymerization of EDOT and the doping of neutral PEDOT by tosylate [28]. We split the amounts of iron(III)·tosylate as 1, 10, 20, 40, 60, and 80 wt % with respect to n -butanol, and EDOT was added to each prepared solution.…”

A NIR-Light-Driven Twisted and Coiled Polymer Actuator with a PEDOT-Tos/Nylon-6 Composite for Durable and Remotely Controllable Artificial Muscle

“…The dark greenish solution was filled into the vessel with the TCN and then it was sucked out of the vessel using a syringe after 3 min. The liquid coating on surface of the TCN was converted into a thin PEDOT-Tos layer (navy-blue color) via thermal polymerization of EDOT with oxidant during drying process in a heating oven at 60 °C for 1 h [ 28 , 29 ]. For eliminating excess oxidants [ 29 ], the resulting PEDOT-Tos layer formed on each TCN was washed with ethanol under magnetic stirring for 20 s and dried in a heating oven at 60 °C for 10 min.…”