Sung-Hae Lee

Investigation of hot carrier effects in n-MOSFETs thick oxide with HfSiON and SiON gate dielectrics

This paper reports the reliability characteristics of poly gated n-MOSFETs with HfSiON and SiON gate dielectrics in both thin and thick oxide of dual gate oxide scheme. Hot carrier stress (HCS) at Isub, max condition on thick oxide is found to be the most critical part among the various reliability concerns. Regardless of gate dielectric and gate oxide thickness, the degradation behavior of the condition of Isub, max and Vg=Vd HCS is mainly SS increase and Vth shift, respectively. Therefore, for precise evaluation of the device reliability, it is necessary that HC immunity at Isub, max stress should be checked in thick oxide transistor below 50 nm design rule era.

Highly-reliable NAND flash memory using Al 2 O 3 -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.