• 文献标题:   Er intercalation and its impact on transport properties of epitaxial graphene
  • 文献类型:   Article
  • 作  者:   YANG MM, DUAN Y, KONG WX, ZHANG JZ, WANG JX, CAI Q
  • 作者关键词:   epitaxial graphene, intercalation, scanning tunneling microscopy stm, electrical transport
  • 出版物名称:   CHINESE PHYSICS B
  • ISSN:   1674-1056 EI 2058-3834
  • 通讯作者地址:  
  • 被引频次:   0
  • DOI:   10.1088/1674-1056/acbc6a
  • 出版年:   2023

▎ 摘  要

Intercalation of atomic species is a practicable method for epitaxial graphene to adjust the electronic band structure and to tune the coupling between graphene and SiC substrate. In this work, atomically flat epitaxial graphene is prepared on 4H-SiC(0001) using the flash heating method in an ultrahigh vacuum system. Scanning tunneling microscopy, Raman spectroscopy and electrical transport measurements are utilized to investigate surface morphological structures and transport properties of pristine and Er-intercalated epitaxial graphene. It is found that Er atoms are intercalated underneath the graphene layer after annealing at 900 degrees C, and the intercalation sites of Er atoms are located mainly at the buffer-layer/monolayer-graphene interface in monolayer domains. We also report the different behaviors of Er intercalation in monolayer and bilayer regions, and the experimental results show that the diffusion barrier for Er intercalated atoms in the buffer-layer/monolayer interface is at least 0.2 eV higher than that in the first/second graphene-layer interface. The appearance of Er atoms is found to have distinct impacts on the electronic transports of epitaxial graphene on SiC(0001).