Scaling effect of device area and film thickness on electrical and reliability characteristics of RRAM

We need to develop stackable, cross-point RRAM device without selection transistor to replace current NAND FLASH technology. Although various materials have been reported, it is difficult to meet device criteria such as high speed operation, low power switching, switching uniformity, endurance, long-term retention and selection device for cross-point array. We have investigated various RRAM devices such as interface switching type, filament type and PMC type. We found that the scaling of device area and film thickness improved device performance and reliability. Understanding of the switching mechanisms and atomic scale film control are necessary to meet the various requirements for future high density nonvolatile memory devices.