Highly-reliable NAND flash memory using Al2O3-inserted inter-poly dielectric

The improvement of device performances has been achieved successfully through OAO IPD EOT scaling, which shows that OAO IPD is applicable to sub-40nm devices which require aggressive scaling of IPD EOT. Charge loss of OAO IPD at high temperature is explained by thermionic emission of alumina traps. Trap profiles of alumina were obtained by monitoring Vth shift above 100°C. OAO IPD shows good data retention at room temperature, which is consistent with trap profiles.