Improvement of retention and endurance characteristics of Si nanocrystal nonvolatile memory device

The nitrided nc-Si floating gate nonvolatile memory device with an ultrathin tunnel (3.5 nm) oxide layer was fabricated. A memory window of 1.3 V was obtained under P/E voltages of ±7 V for 1 ms, and it kept still about 1.1 V after ten years from the extrapolated data of retention characteristics. These results can be attributed to the nitrogen passivation of the traps at the surface of nc-Si. In addition, no detectable variation of the memory window has been displayed after 10⁷ P/E cycles, showing superior endurance characteristics.