Performance and reliability of Hf AlO_x-based interpoly dielectrics for floating-gate Flash memory

摘要

This paper discusses the performance and reliability of aggressively scaled HfAlO_x-based interpoly dielectric stacks in combination with high-workfunction metal gates for sub-45 nm non-volatile memory technologies. It is shown that a less than 5 nm EOT IPD stack can provide a large program/erase (P/E) window, while operating at moderate voltages and has very good retention, with an extrapolated 10-year retention window of about 3 V at 150 ℃. The impact of the process sequence and metal gate material is discussed. The viability of the material is considered in view of the demands of various Flash memory technologies and direction for further improvements are discussed.