Abstract
Both lowering the "reset" current of resistance random access memory (ReRAM) and raising the resistance in the low resistance state are crucial for practical use of ReRAM. These requirements have been satisfied by using a hetero junction structure consisting of transition metal oxides, NiOy/TiOx/Pt, combining direct contact with the NiOy using a W-probe. It is considered that this configuration brought about extreme downsizing of the effective area of both the top and bottom electrodes for NiOy and thus decreased the number of filaments formed in "forming" process. Reducing the number of filaments is essential to these issues.