Imaging of the surface structure of TiO2(110) by noncontact scanning nonlinear dielectric microscopy

Abstract

We have demonstrated that atom-resolved imaging of the n-type wide-gap semiconductor TiO2(110) can be achieved by noncontact scanning nonlinear dielectric microscopy (NC-SNDM). In the NC-SNDM images, parallel bright stripes along the [001] direction, reflecting Ti4+ rows, could be observed. An upward dipole moment was simultaneously measured at each Ti4+ site, although downward polarization could not be detected at the a2- sites. These results suggest that both the topography [εlocal (4)] and the electrical dipole moment [ε local (3)] are influenced by the Ti4+ interaction between the tip and sites. © 2010 American Institute of Physics.