Abstract
Oblique deposition was used to fabricate two metal electrodes separated by a gap of less than 10 nm on a SiO2 substrate. By sweeping voltage between these electrodes, a negative resistance change of several digits was observed in vacuum. In this work, electrodes made of Au, Pd, Pt, and Ta were fabricated, and their electric properties were measured in vacuum. The negative resistance was observed for all of the four metals. The result of the measurements clearly shows the correlation between the voltage at the minimum resistance and the melting point. Also, the calculated temperature rise shows a correlation with the melting point. These facts support the effect that the thermal change of the electrode metal has a considerable effect on the electric properties of the nanogap switch (NGS).