Confocal laser scanning microscopy as a real-time quality-assessment tool for industrial graphene synthesis
Document Type
Article
Publication Date
10-1-2020
Abstract
For the industrial quality control (QC) of the chemical vapor deposition (CVD) graphene, it is essential to develop a method to screen out unsatisfactory graphene films as efficiently as possible. However, previously proposed methods based on Raman spectroscopy or optical imaging after chemical etching are unable to provide non-invasive and fast analysis of large-area graphene films as grown on Cu foil substrates. Here we report that the reflection mode of confocal laser scanning microscopy (CLSM) provides a high-contrast image of graphene on Cu, enabling the real-time evaluation of the coverage and quality of graphene. The reflectance contrast,Rc, was found to be dependent on the incident laser wavelength, of which the maximum was obtained at 405 nm. In addition,Rcdecreases with increasing defect density of graphene. The dependence ofRcon the graphene's quality and laser wavelengths were explained by the tight-binding model calculation based on the Fresnel's interference formula. Thus, we believe that the reflection mode CLSM would be a very powerful quality-assessment tool for the mass production of CVD graphene films grown on Cu.
Keywords
graphene, CLSM, real-time quality-assessment, optical conductivity
Divisions
PHYSICS
Funders
None
Publication Title
2D MATERIALS
Volume
7
Issue
4
Publisher
IOP PUBLISHING LTD
Publisher Location
TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND