Following the first promising results, in 2009 it was decided to anticipate a full industrial demonstrator, making use of the most advanced single exposure litho technology available.
A 1 Gbit NAND memory device was modified by Numonyx to become compatible with the new cell architecture and fully functional samples have been obtained.
First evaluation on the large statistical samples made available by the memory device did show good distribution of written and erased states, even if no programming algorithms were used to compensate for the threshold distribution, and confirmed the absence of cell to cell interference, which is the most important limit to NAND cell scaling. The device was used also to test new technology approaches to the cell architecture, introducing the Band Engineered Tunnel architecture (BET for short). Based on the replacement of the tunnel oxide by an oxide-nitride sandwich, the new structure allows for better programming characteristics and better reliability. Dedicated testing equipment has been developed for fast and reliable assessment of development memories, and it has been demonstrated on the 1Gbit device.