Low-temperature scanning probe microscopy of surface and subsurface charges

摘要

The operation of a cryogenic scanning force microscope is demonstrated with a sensitivity of about 50 fN/(Hz)~(1/2) at 5 kHz modulation. This microscope is used as an electrometer in noncontact mode in order to map the local electrostatic forces and capacitance of several nanostructures at 4.2 K. Capacitance imaging of nanostructured surfaces with subatto-Farad resolution is demonstrated.