Abstract
Resistance Random Access Memory (ReRAM) is often made in the sandwiched structure where a transition metal oxide (TMO) film with polycrystalline structure is placed between the upper and the lower electrodes. Although whether resistance switching effect occurs in grains or in the grain boundary is key issue which decides the downsizing limit of memory cells, it has not been clarified yet. We prepared NiO/Pt structure using the DC sputtering method, and investigated the property of resistance change effect in the local area using conducting atomic force microscope. As a result, it was clarified that the resistance change occurred not in the NiO grain but in the NiO grain boundary. Therefore, it was suggested that the limitation of downsizing is decided according to the grain diameter.
