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

Abstract

Graphene films were grown by chemical vapor deposition on Cu foil. The obtained samples were characterized by Raman spectroscopy, ellipsometry, X-ray photoelectron spectroscopy and electron back-scatter diffraction. We discuss the time-dependent changes in the samples, estimate the thickness of emerging Cu2O beneath the graphene and check the orientation-dependent affinity to oxidation of distinct Cu grains, which also governs the manner in which the initial strong Cu-graphene coupling and strain in the graphene lattice is released. Effects of electropolishing on the quality and the Raman response of the grown graphene layers are studied by microtexture polarization analysis. The obtained data are compared with the Raman signal of graphene after transfer on glass substrate revealing the complex interaction of graphene with the Cu substrate.

Optimization of Graphene Layers Grown on Pt/Ti/SiO2 by Hot Filament Chemical Vapor Deposition

“…The main peak at ≈284.6 eV reveals the presence of sp 2 C peak of graphene and the peak at ≈284.9 is assigned to sp 3 carbon. [ 35 ] Another possible assignment is to ascribe the 284.6 eV peak to monolayer graphene in a decoupled state and the 284.9 eV peak to monolayer graphene in a coupled state. [ 36 ] The term “coupled” describes the graphene that is in direct contact with the substrate, while “decoupled” refers to graphene that is separated from the substrate by intercalated atoms.…”

Atomic Layer Deposition Growth and Characterization of Al2O3 Layers on Cu-Supported CVD Graphene

“…The spectra taken from the as-grown graphene reflect a uniform picture of strong coupling to the Cu substrate [41], manifested by suppressed Raman intensity and a strong blue shift of the G and the 2D bands (≈10 and ≈35 cm −1 , respectively [39,42]). Multiple enhancement of the intensity of all Raman bands of the graphene in sample S1 is observed as an immediate consequence of the ALD process; however, the blue shift largely remains the same.…”

“…The ellipsometric data for Ψ and Δ were fitted within a model consisting of three consecutive layers. The first layer is a semi-infinite oblique copper substrate, whose optical constants were determined from measurements on a freshly prepared two-component Cu/graphene system [39]. The second layer is graphene, with the optical constants of graphite taken from Palik's Handbook of Optical Constants [40] (CompleteEASE 5.10 software).…”