FET No. Raman peaks of graphene films on polycrystalline Cu foil at Step (i) exhibited broad variation compared to those after transferring onto SiO2 (Steps (iii), (iv), and (v)). This is likely due to the polycrystalline nature of Cu foil and wrinkle-like structures that form because of Cu contraction during cooling post-CVD synthesis. The (ωG, ω2D) on Cu foil cannot be vector-decomposed into nH and ε because ω2D depends on Fermi velocity νF. 55, The three parameters-nH, ε, and νF-are independent; therefore, isolating their contributions requires knowledge of at least one. Although νF on Cu foil is expected to be lower than that on SiO2, 55 the spatial variation due to Cu polycrystalline nature renders precisely estimating νF difficult. Therefore, we traced these values across process steps rather than vector-decomposing (ωG, ω2D).