The interface states at the graphene-dielectric substrate are scientifically and industrially important to control the electronic properties for the graphene-based applications. In this report, we present the atomic and electronic structures of graphene on Ge(110), studied by scanning tunneling microscopy and spectroscopy (STM/STS) in an atomic scale. We observed Ge pentamers and ridge structures. The strong electric coupling at the interface and the existence of the Ge pentamers were confirmed by additional peaks at −0.55 V and −0.20 V in the dI/dV spectra. Based on the analysis of the energy gap mappings near the ridges of graphene, extracted from the two-dimensional STS measurements, we could tell the effects of the graphene strain and the interfacial gap distance on the electronic structures of graphene/Ge(110).
This research was supported by the Basic Science Research Program (Grant No. 2015R1A1A1A05027585, 2015M3A7B4050455), the SRC Center for Topological Matter (Grant No. 2011-0030046), the Pioneer Research Center Program (Grant No. NRF-2014M3C1A3053029) and Institute for Basic Science (Grant No. IBS-R011-D1) through the National Research Foundation (NRF) funded by the Ministry of Science and ICT (MSIT) in Korea, by Construction Technology Research Project (Grant No. 18SCIP-B146646-01) funded by the Ministry of Land, Infrastructure and Transport in Korea, and by Industrial Strategic Technology Development Program (Grant No. 10085617) funded by the Ministry of Trade Industry & Energy (MOTIE) in Korea.
