Development and Optimization of Re-Oxidized Tunnel Oxide with Nitrogen Incorporation for the Flash Memory Applications

The reliability properties of NOR flash memory with 65nm node being developed in Samsung electronics are greatly improved by using the newly proposed re-oxidized tunnel oxide. Especially, by optimizing the process variables such as the re-oxidation thickness/time, the partial pressure of NO during annealing, and the kinds of re-oxidizing materials, the Vth shifts post cycling and after post-cycling bake were decreased to the level of 28% and 42% of conventional NO annealed tunnel oxide, respectively.