Organic transistors based on oxidized single-walled carbon nanotube electrodes patterned via simple spray coating

Abstract

We developed a facile spray-printing method to fabricate oxidized single-walled carbon nanotube (Oxy-SWCNT) source-drain electrodes for use in organic field-effect transistors (OFETs). Surface oxidized SWCNT bundles enables the solution processability of Oxy-SWCNT without dispersant. The spray printing of an Oxy-SWCNT solution via a shadow mask led to electrode patterns with excellent transparency and electrical conductivity. Pattern resolution was optimized by adjusting printing volume and substrate temperature. The performance of the pentacene FETs with Oxy-SWCNT electrodes was compared with that of conventional Au electrodes. The FETs with Oxy-SWCNT electrodes exhibited higher charge carrier mobilities, on/off current ratios, and optical transmittances than those of FETs with Au electrodes. The increased device performance of the FETs with Oxy-SWCNT electrodes is due to the low contact resistance resulting from the efficient charge injection and transport across the electrode-channel interface. High work function (−5.1 eV) of the Oxy-SWCNT facilitated the charge injection. Our study demonstrates that Oxy-SWCNTs exhibit exceptional potential as a printable electrode material for OFETs and promise a better replacement for electrodes in transparent and flexible electronics.