Conductance measurements of nanoscale regions with in situ transmission electron microscopy

Conductance measurements of nanostructures with simultaneous transmission electron microscopy (TEM) were performed on thin insulating SrF2 films (3 nm thick) and Fe–SrF2 granular films (10 nm thick) deposited on tip-shaped Au electrodes. By using a movable counter electrode, nanoscale regions were selected for investigation. Systematic measurements taken during the deformation of the SrF2 film by the counter-electrode provided a tunnelling barrier height of about 2.5 eV. The conductance of Fe–SrF2 in nanoscale (∼ 500 nm2) showed the Coulomb staircase like characteristics at room temperature. The staircase period approximately corresponded to the value estimated from the geometry observed by TEM. The feasibility of this method is briefly described.