Statistical simulations of oxide leakage current in MOS transistors and Floating Gate memories

The purpose of this paper is to illustrate a physicallybased model allowing the statistical simulations of oxide leakage currents in MOS transistors and Floating Gate memories. This model computes the leakage current through defects randomly generated in the oxide, in case accounting for the formation of percolation paths. Furthermore, a calculation procedure has been developed to calculate the threshold voltage of FG memories from the simulated oxide leakage current in some reliability conditions, thus allowing to investigate their actual Flash data retention issues and their future trends. To this regard, it will be shown how this simulation model can be used to investigate threshold voltage shift occurring in retention conditions in FG memories after both Program/Erase cycles, i.e. electrical stress and radiation exposure.