This paper discusses the performance and reliability of aggressively scaled HfAlOx-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 rim 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 degrees C. 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. (c) 2008 Elsevier Ltd. All rights reserved.