Silicon Oxide Contamination of Graphene Sheets Synthesized on Copper Substrates via Chemical Vapor Deposition

Abstract

Silicate particle formation on Cu foil during the synthesis of graphene by the commonly used thermal chemical vapor deposition inside of a quartz tube was studied and characterized. The formation of these particles was shown to form simultaneously alongside graphene layers. It is argued that the phase transition of quartz at 573 � C allows copper and hydrocarbon to diffuse into the quartz tube, which in turn causes silicate to precipitate onto the copper foil during the CVD process. Scanning electron microscopy was used to image the contamination and its evolution during prolonged growth times, and energy dispersive X-ray spectroscopy is utilized to identify and trace the potential source of the contamination. Raman spectroscopy and mapping was utilized to demonstrate the negative effects the contamination has on the graphene’s quality and uniformity by showing an increase in