Stability of Densely Contact-Electrified Charges on Thin Silicon Oxide in Air

Abstract

By changing the polarity of charged trap sites, we investigated the stability of densely contact-electrified charges on thin silicon oxide in air using a modified atomic force microscope. For usual silicon oxides with positively charged trap sites, a stable state is obtained only for negative charge deposition, while for modified silicon oxides with negatively charged trap sites, a stable state is obtained only for positive charge deposition. As a result, we concluded that charged trap sites make densely contact-electrified charges with the same polarity unstable due to the strong Coulomb repulsive force.