Modeling of a EEPROM device based on silicon quantum dots embedded in high-k dielectrics

The write/erase (W/E) and data retention characteristics of a memory device based on silicon/oxide/silicon dot/oxide/silicon structure were simulated. It was demonstrated that the replacement of the top blocking SiO2 with high-k dielectric results in several important improvements of memory characteristics. In particular, the application of high-k dielectric as a top oxide enhances the electric field in the tunnel oxide, which allows using a thicker bottom oxide to improve the data retention time. In addition, in a new device the magnitude of the W/E pulse and the programming time can also be reduced. A typical design of the new structure leads to a programming duration of 10 ms and maintains a memory window of 3 V after 10-year data retention.