Two-bit/four-level Pr2O3 trapping layer for silicon-oxide-nitride-oxide-silicon-type flash memory

Abstract

This study proposes and demonstrates a silicon-oxide-nitride-oxide-silicon (SONOS)-type memory device based on a high-k dielectric praseodymium oxide (Pr2O3) trapping layer. In the proposed design, channel hot electron injection programming and band-to-band hot-hole injection erasing allow highly efficient two-bit and four-level device operation. The proposed design also has a total memory window of 5 V, a ten-year V-t retention window larger than 0.8 V between adjacent levels, and enough memory window for 10(5) programming/erasing cycles of endurance. The proposed SONOS-type Pr2O3 trapping layer flash memory exhibits large memory windows, high program/erase speed, good endurance, and good disturbance characteristics. (C) 2012 American Vacuum Society. [DOI: 10.1116/1.3668101]