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Abstract: Memory devices based on MOS structures with Silicon nanocrystals (Si-nc) embedded in the gate oxide have been investigated at the nanoscale with a Conductive Atomic Force Microscope (C-AFM). The high lateral resolution of this technique allows to study extremely small areas (∼300 nm2) and, therefore, the electrical properties of a reduced number of Si-nc. C-AFM experiments have demonstrated that Si-nc enhance the gate oxide electrical conduction due to assisted tunneling. On the other hand, Si-nc can act as trapping centers. The amount of charge stored in Si-nc has been estimated through the change induced in the barrier height measured from the I-V characteristics. The results show that only ∼20% of the Si-nc are charged (in agreement with the macroscopic characterization), demonstrating that C-AFM is a powerful tool to investigate the performance of Si-nc memory devices. [Copyright &y& Elsevier]

We propose double-gate silicon nanocrystal memories (NCMs) with ultrathin body structure. Double-gate NCMs experimentally show larger threshold voltage shift (ΔVth) 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. [ABSTRACT FROM AUTHOR]