High-Quality Monocrystal Graphene for Sound Pressure Sensing

Abstract

Graphene, owing to its excellent mechanical properties, shows promising application prospects in the field of sound pressure sensing, based on the inferences obtained from the Fabry-Perot interferometer (FPI). Currently, chemical vapor deposition (CVD) is an effective method to synthesize graphene artificially. It is challenging to grow large monocrystals by single-point nucleation. However, meeting multiple requirements (e.g., monocrystal and monolayer) is difficult when graphene is grown by multipoint nucleation, which critically limits their practical applications. In this study, we report the growth of monocrystal and monolayer graphene on a centimeter-scale Cu (111) substrate using CVD. Multiphysics coupling establishes the guidance results of gradient and constant temperature fields, obtains a high-purity Cu (111) substrate in a gradient temperature field, and grows monolayer graphene in a constant temperature field. Experiments show that choosing the optimum time during the temperature drop of the monocrystal substrate can cause total area coverage of Cu foil transfer toward Cu (111). The concentration gradient grew larger monocrystals of graphene on the Cu (111) substrate following multipoint nucleation. Furthermore, multilayer graphene with good uniformity was synthesized by wet transfer process. This work presents an effective resolution to enhance the sensing capability for graphene-based pressure sensors.

Keywords: Monolayer monocrystal graphene, monocrystallization of Cu (111), chemical vapor deposition, multilayer graphene