Preparation of Copper Surface for the Synthesis of Single-Layer Graphene

Abstract

Chemical vapor deposition synthesis of graphene on copper foil from methane is the most promising technology for industrial production. However, an important problem of the formation of the additional graphene layers during synthesis arises due to the strong roughness of the initial copper foil. In this paper, various approaches are demonstrated to form a smooth copper surface before graphene synthesis to reduce the amount of few layer graphene islands. Six methods of surface processing of copper foils are studied and the decrease of the roughness from 250 to as low as 80 nm is achieved. The correlation between foil roughness and the formation of the additional layer is demonstrated. Under optimized conditions of surface treatment, the content of the additional graphene layer drops from 9 to 2.1%. The quality and the number of layers of synthesized graphene are analyzed by Raman spectroscopy, scanning electron microscopy and measurements of charge mobility.

Field Electron Emission from Crumpled CVD Graphene Patterns Printed via Laser-Induced Forward Transfer

“…The surface coverage density of the transferred carbon nanomaterial was larger in the case of multipass irradiation, which was confirmed by optical ( Figure 2 ) and electron ( Figure 3 ) microscopy. To estimate the percentage of surface coverage, we analyzed the SEM images with the graphics software previously used to calculate the amount of multilayer graphene on the surface [ 39 ]. After converting the SEM image to the black–white format, each pixel was represented by ‘0’ and ‘1’, and the percentage of surface coverage was calculated as 10.6 % for the single-pass and 17.9 % for the three-pass irradiated areas.…”

Growth and Characterization of Graphene Layers on Different Kinds of Copper Surfaces

“…Electropolishing has been frequently applied as part of the Cu foil pretreatment to lower its surface roughness and to achieve better quality of the grown graphene [ 37 , 38 ]. Here, we compare the characteristics of graphene grown on Cu foil electropolished prior to the CVD growth and on Cu foil that has not undergone such pretreatment.…”

Optical data of graphene grown by chemical vapor deposition on copper foil using spectroscopic ellipsometry

“…Ellipsometric parameters of materials on copper foil substrates were collected at an incidence angle of 70 degrees [1] , [2] , [3] . The amplitude ratio of materials on copper foil substrate vs. wavelength was generated on separate graphs based on copper foil substrate thickness and methane flow rate [4] , [5] , [6] , [7] .…”