Nonvolatile Schottky Barrier Multibit Cell With Source-Side Injected Programming and Reverse Drain-Side Hole Erasing

This paper presents a novel Schottky barrier multibit cell with source-side injected programming and reverse drain-side hole erasing. Based on the unique ambipolar conduction of Schottky barrier devices, the source Schottky barrier promotes the amounts of hot electrons at a positive gate voltage to perform source-side injected programming, whereas the drain Schottky barrier enhances the generations of hot holes at a negative gate voltage to carry out reverse drain-side erasing. The proposed Schottky barrier charge-trapping cells are numerically demonstrated to exhibit low-voltage and high-efficiency programming/erasing without the presence of any gate versus source/drain bias tradeoff. The tight and matched distributions of injected carriers make this Schottky barrier cell excellent in future multibit-cell applications.