Influence of Solvents in Micropatterning of Semiconductors by Microcontact Printing and Application to Thin-Film Transistor Devices

Abstract

Micropatterning of organic semiconductors without etching was successfully achieved by microcontact printing (µCP). We used poly(3-hexylthiophene) (P3HT) as a semiconductive conjugated polymer. We have shown that the width of the fabricated pattern can be controlled by the solvent properties of P3HT solution. Specifically, chloroform (CHCl3) was an effective solvent in fabricating micropatterns. We have succeeded in fabricating a pattern narrower than the corresponding pattern of a poly(dimethylsiloxane) (PDMS) elastomer stamp by controlling the solvent properties. Furthermore, we fabricated top-contact (TC) organic thin-film transistors (OTFTs) by stacking poly(3,4-ethylenedioxythiophene)/poly(4-stylenesulfonate) (PEDOT/PSS) thin films using µCP to form source and drain electrodes on the printed P3HT surface. We demonstrate that the fabricated OTFTs successfully operate. These results show that µCP is promising for application to various kinds of devices that need micropatterning.