Electronic states of sulfur vacancies formed on a MoS₂ surface

Sulfur vacancies formed on a MoS₂ surface have been predicted to have electronic states at the Fermi level, and to work as conductive atomic scale structures. We made sulfur vacancies on a MoS₂ surface by removing sulfur atoms using scanning tunneling microscopy (STM) induced field evaporation, and measured the current-voltage (I/V) characteristics of the vacancies. The I/V curve measured at the vacancies showed a linear increase at a zero bias region, indicating the existence of electronic states at the Fermi level. On the other hand, the I/V curve measured at a clean surface showed a gap of about 1 eV around the Fermi level, as was expected from the theoretical calculation. We also successfully carried out manipulation of Au nanoislands, which will be used as nanopads to be connected to a sulfur vacancy chain.