title: Atomic dipole moment distribution of Si atoms on a Si111-(7 x 7) surface studied using noncontact scanning nonlinear dielectric microscopy.
abstract: A local atomic electric dipole moment distribution of Si atoms on Si(111)-(7 x 7) surface is clearly resolved by using a new technique called noncontact scanning nonlinear dielectric microscopy. The dc-bias voltage dependence of the atomic dipole moment on the Si(111)-(7 x 7) surface is measured. At the weak applied voltage of -0.5 V, a positive dipole moment is detected on the Si adatom sites, whereas a negative dipole moment is observed at the interstitial sites of inter Si adatoms. Moreover, the quantitative dependence of the surface dipole moment as a function of the applied dc voltage is also revealed at a fixed point above the sample surface. This is the first successful demonstration of direct atomic dipole moment observation achieved in the field of capacitance measurement.
authors.affiliation: Research Institute of Electrical Communication, Tohoku University 2-1-1 Katahira, Sendai 980-8577, Japan. cho@riec.tohoku.ac.jp
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Cho
authors.forename: Ryusuke
authors.initials: R
authors.lastname: Hirose