• 文献标题:   Time Evolution Studies on Strain and Doping of Graphene Grown on a Copper Substrate Using Raman Spectroscopy
  • 文献类型:   Article
  • 作  者:   LEE U, HAN Y, LEE S, KIM JS, LEE YH, KIM UJ, SON H
  • 作者关键词:   graphene, cu oxidation, strain, pdoping, anticorrosion barrier
  • 出版物名称:   ACS NANO
  • ISSN:   1936-0851 EI 1936-086X
  • 通讯作者地址:   Chung Ang Univ
  • 被引频次:   7
  • DOI:   10.1021/acsnano.9b08205
  • 出版年:   2020

▎ 摘  要

The enhanced growth of Cu oxides underneath graphene grown on a Cu substrate has been of great interest to many groups. In this work, the strain and doping status of graphene, based on the gradual growth of Cu oxides from underneath, were systematically studied using time evolution Raman spectroscopy. The compressive strain to graphene, due to the thermal expansion coefficient difference between graphene and the Cu substrate, was almost released by the nonuniform Cu2O growth; however, slight tensile strain was exerted. This induced p-doping in the graphene with a carrier density up to 1.7 X 10(13) cm(-2) when it was exposed to air for up to 30 days. With longer exposure to ambient conditions (>1 year), we observed that graphene/Cu2O hybrid structures significantly slow down the oxidation compared to that using a bare Cu substrate. The thickness of the CuO layer on the bare Cu substrate was increased to approximately 270 nm. These findings were confirmed through white light interference measurements and scanning electron microscopy.