Construction of Independently Driven Double-Tip Scanning Tunneling Microscope

Abstract

We construct an independently driven double-tip scanning tunneling microscope (STM) for evaluating electrical conduction within the micrometer scale under ambient condition. Each STM unit has an atomic resolution and enables the tip to approach an intended position within 10 mm² on the surface with three course driving stages and a piezoelectric devices which has a maximum scan area of 15 μm. The current flow between the two tips through the material can be detected in the range from 0.1 pA to 100 nA. The conductivity measurement of the poly(3-octylthiophene) thin films was demonstrated using this system.