Metal nano-dot memory for high-density non-volatile memory application

New nonvolatile memory with extremely high density metal nanodots, MND (metal nanodot) memory, is proposed for a future high density nonvolatile memory application (Takata et al., 2003). Fundamental characteristics of the MND memory were evaluated. MND film is used as a charge retention layer in the MND memory. The MND film consists of the thin oxide film that dispersively includes high density metal dots with nanoscale. The MND film is formed by using sputtering technique with a special sputtering target. The diameter and the density of the MND in the film are typically 2-3 nm and around 2 × 10¹³/cm², respectively, which were superior to that of Si nanodot memory. Nonvolatile memory operation at a relatively low voltage and good endurance characteristic were confirmed in the MND memory fabricated according to the conventional MOS process.