Multi-gate non-volatile memories with nanowires as charge storage material

Multi-gate non-volatile memory (NVM) cell is a promising approach in the next generation. In this work, the performance of NVMs using nanocrystals (NCs) and nanowires (NWs) as charge trapping materials were evaluated by three-dimensional simulation. It is found that the NWs located at different positions have different charge injection speeds. And the NW density will strongly affect the charge injection efficiency. The NW at channel center can result in large memory window and acceptable channel controllability. Although the total charges injected into NWs is lower than that injected into NCs under the same programming condition, using NWs as charge trapping material exhibits larger memory window and better channel controllability. It is suggested that the NW is a better choice than NC to be charge storage material from the perspective of memory performance.

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