Enhancement of charge storage performance in double-gate silicon nanocrystal memories with ultrathin body structure

We propose double-gate silicon nanocrystal memories (NCMs) with ultrathin body structure. Double-gate NCMs experimentally show larger threshold voltage shift (ΔV_th) and longer charge retention time than single-gate NCMs. These superior behaviors in double-gate NCMs are explained by the increase in the body potential due to electrons in one side nanocrystals that prevent electrons in the other side nanocrystals from escaping. Thinner transistor body enhances the mutual influence between electrons in both sides. It is also found that the endurance characteristics are also improved by the reduced potential difference in the tunnel oxide.