Monolayer graphene epitaxially grown on SiC(0001) was etched by H-plasma and studied by scanning tunneling microscopy and spectroscopy. The etching created partly hexagonal nanopits of monatomic depth as well as elevated regions with a height of about 0.12 nm which are stable at T = 78 K. The symmetric tunnel spectrum about the Femi energy and the absence of a 6×6 corrugation on the elevated regions suggest that in these regions the carbon buffer layer is decoupled from the SiC substrate and quasi-free-standing bilayer graphene appears at originally monolayer graphene on the buffer layer. This is a result of passivation of the SiC substrate by intercalated hydrogen as in previous reports for graphene on SiC(0001) heat treated in atomic hydrogen.
@article{arxiv.1812.06402,
title = {STM/S Observations of Graphene on SiC(0001) Etched by H-plasma},
author = {André E. B. Amend and Tomohiro Matsui and Hiroki Hibino and Hiroshi Fukuyama},
journal= {arXiv preprint arXiv:1812.06402},
year = {2019}
}
Comments
6 pages, 5 figures, ACSIN-14 and ICSPM-26 proceedings