• 文献标题:   Effect of 6H-SiC (11(2)over-bar0) substrate on epitaxial graphene revealed by Raman scattering
  • 文献类型:   Article
  • 作  者:   LIN JJ, GUO LW, JIA YP, CHEN LL, LU W, HUANG J, CHEN XL
  • 作者关键词:   epitaxial graphene, 6hsic 11 2 overbar0, temperature dependent raman scattering
  • 出版物名称:   CHINESE PHYSICS B
  • ISSN:   1674-1056 EI 1741-4199
  • 通讯作者地址:   Chinese Acad Sci
  • 被引频次:   3
  • DOI:   10.1088/1674-1056/22/1/016301
  • 出版年:   2013

▎ 摘  要

A nonpolar SiC(11 (2) over bar0) substrate has been used to fabricate epitaxial graphene (EG). Two EGs with layer numbers of 8-10 (referred to as MLG) and 2-3 (referred to as FLG) were used as representative to study the substrate effect on EG through temperature-dependent Raman scattering. It is found that Raman lineshifts of G and 2D peaks of the MLG with temperature are consistent with that of free graphene, as predicted by theory calculation, indicating that the substrate influence on the MLG is undetectable. While Raman G peak lineshifts of the FLG to that of the free graphene are obvious, however, its lineshift rate (-0.016 cm(-1)/K) is almost one third of that (-0.043 cm(-1)/K) of an EG on 6H-SiC (0001) in the temperature range from 300 K to 400 K, indicating a weak substrate effect from SiC (11 (2) over bar0) on the FLG. This renders the FLG with a high mobility around 1812 cm(2).V-1.s(-1) at room temperature even with a very high carrier concentration about 2.95 x 10(13) cm(-2) (p-type). These suggest SiC (11 (2) over bar0) is more suitable for fabricating EG with high performance.