Experimental and theoretical investigation of nano-crystal and nitride-trap memory devices

In this paper, we propose a thorough experimental and theoretical investiga tion of memory-cell structures employing discrete-trap type storage nodes, using either natural nitride traps or semiconductor nano-crystals, thus ope rating with a small finite number of electrons, A detailed account of stati c and dynamic charging/discharging phenomena occurring in these devices is given, based on bias-, time-, and temperature-dependent measurements. A com prehensive interpretation of experimental results is proposed by means of a physical modeling, In particular, two different models are proposed. The f irst one consists in a modified floating-gate-like approach, while the seco nd one is a trap-like approach, relying on the Shockley-Read-Hall statistic s, Using these two approaches, some general behavior laws for memory operat ion are formulated. Considerations on the suitability of each model on the particular structures are suggested.