Contact-type scanning nonlinear dielectric microscopy (SNDM) can measure the distribution of linear and nonlinear dielectric properties of insulators with sub-nanometre resolution. SNDM, however, has a tip-abrasion problem, and this problem is one of the obstacles in obtaining a high-quality image.In this paper, in order to improve SNDM, we propose a non-contact scanning nonlinear dielectric microscopy (NC-SNDM) which focuses on the nonlinear dielectric signal for controlling the non-contact condition. With the NC-SNDM technique, topographic and SNDM images were obtained successfully. Moreover, from the calculation results, it was confirmed that NC-SNDM has atomic-order sensitivity to the gap between the tip and the specimen.

Non-contact scanning nonlinear dielectric microscopy (NC-SNDM) operated under ultra high vacuum (UHV) conditions was developed. This microscopy enables the simultaneous measurement of the topography and dielectric properties of a specimen. For electrically conductive materials, the tunnelling current is also measurable. The atomic structure of Si(111)7 × 7 was successfully resolved using this new SNDM technique. This is the first report on the achievement of atomic resolution in capacitance measurements.

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New bis(phenazasiline) compounds were prepared and a thin film transistor (TFT) device containing bis(phenazasiline) derivatives was fabricated. The bis(phenazasiline)s, prepared from 2-bromo-8-methylphenazasiline, were effective materials for TFT. Obtained bis(phenazasiline) derivatives were considered to be model compounds of phenazasiline-containing polymers in the prediction of TFT properties.

The effect of adsorbed water on the signal of scanning nonlinear dielectric microscopy (SNDM) is reported. By measuring SNDM image variation under various measurement conditions and by computing the theoretical SNDM signal corresponding to these conditions, we verified that the adsorbed water strongly affects the signal strength, depth sensitivity, and resolution of SNDM. From this study, we find that it is necessary to consider adsorbed water for detailed measurement of the surface polarization state by SNDM. In addition, we also confirmed that the surface paraelectric layer on a LiTaO3 single crystal grows upon heat treatment.