When nanoparticles are embedded in the insulating layer of a MOS capacitor, the device exhibits hysteretic behavior. Depending on whether there are charges stored in the nanoparticles or not, the device shows different characteristics, and thus can act as a memory cell. External driving power is necessary only for the transition between the “charged” and “uncharged” states, and in that sense this memory is non-volatile. Previous work in the field contains many experimental and theoretical projects, attempting to understand, quantify, and utilize this intriguing effect of charge trapping which enables memory.

The objective of this study is to understand the dynamics of the charging and discharging of the traps, and to explore effects due to the discrete energy levels of the nanoparticle. We propose a simplified model based on the rate equations for the occupation probability of charges in the nanoparticles. In the derivation of this model we employ the theories of quantum dots and of charge tunneling in semiconductors. Finally, we implement this model and compare our numerical results to experimental data.