Graphene quality evaluation by Van der Pauw-Hall Method

Abstract

Evaluating graphene quality is crucial for both industrial applications and academic research. Traditional methods like Optical Microscope, Raman Spectroscope, Scanning and Transmission Electron Microscope, while common, face challenges in convience and providing electrical performance. To address these limitations, a cost-effective and rapid method was introduced for assessing macroscopic quality of graphene. This technique involves fine-tuning carrier concentration over 1013 cm-2 by controlling hydrochloric acid (HCl) doping time. Utilizing the Van der Pauw-Hall system, it tracks carrier concentration changes of graphene, allowing for mobility measurement under consistent carrier conditions. This facilitates a direct comparison of different graphene samples. The method shows reproducibility in evaluating HCl-doped graphene, which is consistent with the Raman characterizations. This advancement in graphene evaluation, focusing on mobility comparison at identical carrier concentrations, sets the stage for standardized assessments in the graphene industry.