Аннотация:We studied a Si(100)-2 × 1 surface by non-contact scanning nonlinear dielectric microscopy (NC-SNDM). Simultaneously taken images of the topography and electric dipole moment distribution show that negative electric dipole moments are locally formed on individual dimers on the surface. In addition, we obtained the dc bias voltage dependence of the εlocal(3) signal on a specific dimer by using an atom-tracking technique with NC-SNDM. We observed that the electric dipole induced a surface potential of around −250 mV on the dimer.