Analysis of Charge Retention Characteristics for Metal and Semiconductor Nanocrystal Non-volatile Memories

A charge retention model for nanocrystal MOSFET memory structure is proposed, taken into account the quantum confinement effect, to account for the better retention characteristics of metal nanocrystal memories over their semiconductor counterparts observed in the experiment. Simulation results are in consistent with experimental data, which confirms the validity of this model. The impact of nanocrystal size, tunneling dielectric material (especially high-К dielectrics) and thickness on the retention characteristics are investigated for both of the metal nanocrystal and semiconductor nanocrystal memories.