A 30-inch roll-to-roll process for producing high-quality graphene films for flexible transparent electrodes is reported. The method involves chemical vapor deposition (CVD) growth of graphene on Cu substrates, followed by multiple roll-to-roll transfer and wet chemical doping to enhance electrical properties. The resulting graphene films exhibit a sheet resistance as low as ~30 Ω/sq with ~90% transparency, surpassing commercial transparent electrodes like indium tin oxide (ITO). Monolayer graphene films show sheet resistances as low as ~125 Ω/sq with 97.4% optical transmittance and half-integer quantum Hall effect, indicating high quality. A touch screen panel device based on these graphene electrodes demonstrates excellent mechanical and electrical performance. Graphene and related materials have attracted significant attention due to their unique electrical, mechanical, and chemical properties. Recent advances in CVD allow the growth of large-area graphene on Cu substrates. The process involves growing graphene on Cu foils at high temperatures (~1000°C), followed by roll-based transfer onto flexible substrates. This method enables the production of large-scale, high-quality graphene films with excellent scalability and processability. The roll-to-roll transfer process includes adhesion of polymer supports, etching of Cu layers, and release of graphene layers onto target substrates. The process is efficient and cost-effective, allowing for the production of multilayer graphene films with enhanced electrical and optical properties. The electrical properties of the graphene films are further improved through p-doping with nitric acid (HNO3), which significantly reduces sheet resistance. The resulting graphene films show a sheet resistance as low as ~30 Ω/sq with ~90% optical transmittance, surpassing ITO. The unique electronic band structure of graphene allows for modulation of charge carrier concentrations, enhancing electrical properties. The roll-to-roll process enables the continuous production of large-area graphene films, making them suitable for flexible transparent electrodes. The study demonstrates the potential of roll-to-roll production for large-scale graphene films, which can replace ITO in transparent electrodes. The method offers excellent scalability, processability, and flexibility, making it a promising candidate for commercial applications. The results highlight the potential of graphene-based transparent electrodes for flexible electronics and other applications.A 30-inch roll-to-roll process for producing high-quality graphene films for flexible transparent electrodes is reported. The method involves chemical vapor deposition (CVD) growth of graphene on Cu substrates, followed by multiple roll-to-roll transfer and wet chemical doping to enhance electrical properties. The resulting graphene films exhibit a sheet resistance as low as ~30 Ω/sq with ~90% transparency, surpassing commercial transparent electrodes like indium tin oxide (ITO). Monolayer graphene films show sheet resistances as low as ~125 Ω/sq with 97.4% optical transmittance and half-integer quantum Hall effect, indicating high quality. A touch screen panel device based on these graphene electrodes demonstrates excellent mechanical and electrical performance. Graphene and related materials have attracted significant attention due to their unique electrical, mechanical, and chemical properties. Recent advances in CVD allow the growth of large-area graphene on Cu substrates. The process involves growing graphene on Cu foils at high temperatures (~1000°C), followed by roll-based transfer onto flexible substrates. This method enables the production of large-scale, high-quality graphene films with excellent scalability and processability. The roll-to-roll transfer process includes adhesion of polymer supports, etching of Cu layers, and release of graphene layers onto target substrates. The process is efficient and cost-effective, allowing for the production of multilayer graphene films with enhanced electrical and optical properties. The electrical properties of the graphene films are further improved through p-doping with nitric acid (HNO3), which significantly reduces sheet resistance. The resulting graphene films show a sheet resistance as low as ~30 Ω/sq with ~90% optical transmittance, surpassing ITO. The unique electronic band structure of graphene allows for modulation of charge carrier concentrations, enhancing electrical properties. The roll-to-roll process enables the continuous production of large-area graphene films, making them suitable for flexible transparent electrodes. The study demonstrates the potential of roll-to-roll production for large-scale graphene films, which can replace ITO in transparent electrodes. The method offers excellent scalability, processability, and flexibility, making it a promising candidate for commercial applications. The results highlight the potential of graphene-based transparent electrodes for flexible electronics and other applications.