FRANK Luděk Institute of Scientific Instruments AS CR, v.v.i.

Examination of Graphene with Very Slow Electrons

Co-authors MIKMEKOVÁ Eliška

Although the graphene is available and extremely intensively studied for nearly full decade, methods for its examination and diagnostics require replenishing. Even checking continuity of the layers and reliable counting the layers of graphene and other 2D crystals should be performed easier. Scanning electron microscopy with slow and very slow electrons offers a novel tool enabling one to see the graphene samples at nanometer or even sub-nanometer lateral resolution in transmitted as well as reflected electrons and to count reliably the layers in both imaging modes. Thus, diagnostics can be performed on free-standing graphene samples as well as on graphene grown on surfaces of bulk substrates. Moreover, bombardment with very slow electrons acts as an ultimate cleaning procedure removing adsorbed gases from crystal surfaces, which can be monitored in the scanned transmission electron images taken below 50 eV.