Microstructure fabrication process induced modulations in CVD graphene

Abstract

The systematic Raman spectroscopic study of a “mimicked” graphene device fabrication is presented. Upon photoresist baking, compressive stress is induced in the graphene which disappears after it is removed. The indirect irradiation from the electron beam (through the photoresist) does not significantly alter graphene characteristic Raman peaks indicating that graphene quality is preserved upon the exposure. The 2D peak shifts and the intensity ratio of 2D and G band, I(2D)/I(G), decreases upon direct metal deposition (Co and Py) suggesting that the electronic modulation occurs due to sp2 C-C bond weakening. In contrast, a thin metal oxide film deposited graphene does not show either the significant 2D and G peaks shift or I(2D)/I(G) decrease upon the metal deposition suggesting the oxide protect the graphene quality in the fabrication process.

Modification of Graphene Oxide/V2O5·nH2O Nanocomposite Films via Direct Laser Irradiation

“…The G 1 component is associated with the in-plane stretching vibration . The G 2 component can be attributed to the bond angle disorder and surface functional groups (O–H). , The I D / I G1 and I G2 / I G1 intensity ratios were found to be 0.98 and 0.52 for GO. The second order overtone, 2D, is due to the two-phonon double resonance, while the D+G band is attributed to higher structure disorder of GO…”