Photolithographic Transparent Flexible Graphene Oxide/PEDOT:PSS Electrode Array for Conformal Organic Transistor

Abstract

A facile and damage-free patterning pro- cess was proposed to solve the incompatibility in the traditional photolithography process by introducing graphene oxide (GO) as a protective layer for poly (3,4-ethylenedioxythiophene): polystyrene (PEDOT:PSS) film. As a result, a high-resolution GO/PEDOT:PSS elec- trode array with a feature size down to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$3 ~\mu \text{m}$ </tex-math></inline-formula> was fabricated. Moreover, the PEDOT:PSS films exhibit average optical transparency up to 92.6% in the visible light range, excellent conductivity (~2000 S cm−1), and high conformability. Based on the GO/PEDOT:PSS electrode array, the confor- mal organic field-effect transistors with the highest mobility of up to 1.4 cm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{{2}}\,\,\text{V}^{-{1}}\,\,\text{s}^{-{1}}$ </tex-math></inline-formula> and average mobility of 0.83 cm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{\vphantom {\text {D}^{\text {j}}}{2}}\,\,\text{V}^{-{1}}\,\,\text{s}^{-{1}}$ </tex-math></inline-formula> by layer-by-layer lamination were successfully fabricated. Our process was highly compatible with traditional photolithographic patterning techniques, which may provide a route for the integration of complex soft electronics.