Published online by Cambridge University Press: 20 August 2014
The author reports that the spatial luminescent distribution from Cu substrate is in special sync with the Cu substrate morphology in terms of suspended formation of the deposited graphene fabricated via chemical vapor deposition. Moreover, the Raman 2D and G peak position of the graphene relatively shift to high frequency on the even Cu foil domain, showing more compressive strain than the uneven region. The author can reveal that the reducing compressive strain by virtue of the uneven Cu domains in order to minimize the interaction between graphene and Cu substrate has one of the important roles in forming suspended graphene. Current mapping in small dimension additionally shows that the current flow is mostly detected at the nano-terrace regions than the even, further substantiating the significance of the detailed underlying Cu substrate morphology. The author can also shows the correlation between the graphene strain revealed via 2D peak shift on Cu surface and the sheet resistance value of graphene on PET substrate, suggesting the degree of suspended formation of the graphene on Cu may be one of the important factors in increasing electrical performance on PET substrate.