SILICON SINGLE-ELECTRON MEMORY USING ULTRA-SMALL FLOATING GATE

A single-electron memory having a ultra-small floating gate on a narrow channel is studied theoretically and experimentally. This device is fabricated based on Si by using self-aligned process, and exhibits quantized threshold voltage shifts and hysteresis curves in the electrical characteristics at room temperature. These are basic operation of the single-electron memory. A novel method to form small metal dots is also developed. Sn nanocrystals are formed in thin, thermally grown SiO2 layers by using low energy ion implantation followed by thermal annealing. Current-voltage characteristics of a diode in which Sn dots are embedded show a clear Coulomb gap and Coulomb staircases. These techniques are promising for making single-electron memories to be practical.