A novel Multi - Nitridation ONO interpoly dielectric (MN-ONO) for highly reliable and high performance NAND Flash memory

Multi-Nitridation ONO has been demonstrated for the first time. Significant improvement are obtained in NAND Flash performance and reliability. (1) 1V program voltage reduction owing to 10A EOT (equivalant oxide thickness ) reduction (2) More than 20% tighter cell Vt distribution width can be achieved from ONO bird's beak free due to supressing encroachment of gate re-oxidation by Floating Gate (FG) / top oxide nitridation. And also, (3) good data retention can be realized by applying plasma oxidation on bottom oxide to suppress the trap assisted charge loss. MN-ONO is a promising technology for high density NAND Flash beyond 40nm generation.