A Localized Two-Bit/Cell Nanowire SONOS Memory Using Schottky Barrier Source-Side Injected Programming

A localized two-bit/cell silicon nanowire silicon-oxide-nitride-oxide-silicon memory is experimentally presented for the use in future multibit/cell or NOR Flash applications. Instead of conventional channel-hot-electron programming used in charge-trapping cells, the localized charge storages are performed using the Schottky barrier source-side electron programming. The selection of applying a drain or source voltage determines the injected location of storage bits during cell programming. The locally trapped charges decouple the conduction of electron current from the ambipolar hole current to generate an enlarged sensing window. The results of reliability and characterization tests confirm the localized storage cells preserve excellent low voltage, operation speed, cycling endurance, and thermal retention as the nonlocalized counterparts.