The Polymer Society of Korea

Abstract

This study presents a photolithography (PR)-free platform for patterned ambipolar field-effect transistors (FETs) based on semiconductor single-walled carbon nanotubes (sc-SWNTs), enabled by a chemically crosslinkable self-assembled monolayer (SAM). High-purity sc-SWNT ink was obtained through a conjugated polymer wrapping method. The sc-SWNTs were chemically immobilized onto substrates through UV-induced crosslinking between the nanotubes and the SAM. Compared to physically adsorbed CNT films, this chemical crosslinking strategy enables the formation of CNT channels with thicknesses of only a few nanometers, while allowing shadow-mask-based patterning and providing robust post-processing stability. Consequently, this approach offers a simpler and more process-compatible manufacturing route than conventional PR-based patterning. As a result, CNT FETs exhibited clear ambipolar characteristics, with an average mobility of approximately 5 cm² V^-1 s^-1 and an on/off ratio about 10⁶.