Improved Reliability of a High-k IPD Flash Cell through use of a Top-oxide

We report Flash cell write/erase and reliability data from a 2Mb demonstrator processed using a 0.13μm based eFlash technology comprising the high-k material, aluminum oxide (Al
₂
O
₃
) within the inter-poly dielectric (IPD) layer. With bottom and top-oxides (SiO
₂
) completing the OAO IPD stack, producing an EOT of 9.5nm, a 2.0V improvement in programming voltage over a Flash cell with a conventional ONO IPD is obtained. Retention studies reveal both the important role of the top-oxide, and, at elevated temperature, the robustness of the OAO construction.