30 inch Roll-Based Production of High-Quality Graphene Films for Flexible Transparent Electrodes

TL;DR

This paper demonstrates large-scale production of high-quality graphene films with excellent electrical and optical properties suitable for flexible transparent electrodes, using roll-to-roll transfer and chemical doping techniques.

Contribution

It introduces a scalable roll-to-roll process for producing high-quality graphene films with superior electrical and optical performance compared to traditional materials.

Findings

Graphene films achieved ~30 Ohm/sq sheet resistance at 90% transparency.

Monolayer graphene shows ~125 Ohm/sq resistance with 97.4% transmittance.

Fabricated touch screen panel exhibits excellent mechanical and electrical performance.

Abstract

We report that 30-inch scale multiple roll-to-roll transfer and wet chemical doping considerably enhance the electrical properties of the graphene films grown on roll-type Cu substrates by chemical vapor deposition. The resulting graphene films shows a sheet resistance as low as ~30 Ohm/sq at ~90 % transparency which is superior to commercial transparent electrodes such as indium tin oxides (ITO). The monolayer of graphene shows sheet resistances as low as ~125 Ohm/sq with 97.4% optical transmittance and half-integer quantum Hall effect, indicating the high-quality of these graphene films. As a practical application, we also fabricated a touch screen panel device based on the graphene transparent electrodes, showing extraordinary mechanical and electrical performances.