Tunneling/shear force microscopy using piezoelectric tuning forks for characterization of topography and local electric surface properties

Characterization of novel nanoelectronic structures and materials requires advanced and high-resolution diagnostic methods. In this article new approach for high sensitivity measurements of electric surface properties using scanning probe microscopy is presented. In this procedure topography and tunneling current flowing between the metallic tip and the surface are observed simultaneously. In our design piezoelectric tuning fork equipped with metallic tip in shear force microscope is used.In our experiments we also applied an additional feedback loop to maintain constant tunneling current while scanning over electrical inhomogeneous surfaces. In this way crosstalk between topography and tunneling current measurements is reduced. The described method was tested on nanocrystalline diamond and gold thin films deposited on silicon substrates.