Abstract Although various applications extensively utilize polymer-assisted graphene transfer step, the role of residual polymer on graphene was not well-understood. Here, we report the effect of poly (methyl methacrylate) (PMMA) on chemical vapor deposition-grown hexagonal graphene via Raman spectroscopy. Analysis of bare-, PMMA-covered supported, and PMMA-covered suspended graphene exhibits that their G and 2D band positions are progressively downshifted in that order. Mapping of spatial G and 2D band shifts into doping and strain contributions shows that PMMA residue exerts moderate 0.15% tensile strain on graphene/substrate, as compared to that of bare graphene. During this tensile strain, residual PMMA-covered graphene maintains its doping level as much as bare graphene does.
Bibliographical noteFunding Information:
The authors appreciate J. Kim for help with the contrast simulation. This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology ( 2014R1A1A2055572 ), and in part by the Yonsei University Future-Leading Research Initiative of 2014. Appendix A
All Science Journal Classification (ASJC) codes
- Materials Science(all)