Physical description of anomalous charge loss in floating gate based NVM's and identification of its dominant parameter

A model for anomalous charge loss is presented based on the physical description of charge transport through the tunnel oxide. This physics based model considers phonon-assistance as well as arbitrary 3-dimensional distributions of oxide defects (electron traps). After identifying the trap-trap distance as the most important parameter the 3-dimensional model can be simplified to a tunneling model, which describes one tunneling step only. The consistency of the simplified 1-step model with the percolation model for anomalous charge loss description is shown. Also the accelerated testing method for anomalous charge loss is confirmed and validated by these models.