One-Step Fabrication of Graphene Transistors Based on Coffee-Ring Structure of Chemically Exfoliated Graphene Derivatives

Abstract

Graphene has received much attention as a promising electric material for electrodes or channel region of transistor. However, its use in transistor fabrication requires many different processes like a transfer process to a target substrate, patterning through photolithography, preparing the source and the drain electrodes, and et cetera, all of which increases the manufacturing cost. Recently creating patterns for channels or electrodes via solution process has been proposed as a way to reduce the cost. When a spilled drop of dispersed graphene ink dries on a solid surface in the solution-based pattering process, it leaves a dense, ring-like deposit along the perimeter and this is known as the “coffee-ring effect”. Here, we introduce a facile process to prepare the channel and source/drain electrodes in one-step solution process for a graphene tr ansistor using a coffee-ring effect, and have proven its functionality. Thickness and electric properties of both the channel region and the electrodes have ben investigated with conductive AFM. An XPS was performed to investigate the effects of reduction and the conductivity change in graphene oxide(GO) in photo-reduction process by Intensely Pulsed White Light (IPWL).