Silicon-quantum-dots (Si-QDs) with an areal density as high as ∼10¹²cm^-2 were self-assembled on thermally-grown SiO₂ by low pressure CVD using Si2H6, in which OH-terminated SiO₂ surface prior to the Si CVD was exposed to GeH₄ to create nucleation sites uniformly. After thermal oxidation of Si-QDs surface, two-dimensional electronic transport through the Si-QDs array was measured with co-planar Al electrodes evaporated on the array surface. Random telegraph signals were clearly observed at constant applied bias conditions in dark condition and under light irradiation at room temperature. The result indicates the charging and discharging of a dot adjacent to the percolation current path in the dots array.