Abstract
The memory characteristics of atomic layer deposited high-k Hf-based nanocrystals embedded in high-κ Al2O3 films in an n-Si/SiO2/HfO2/high-k nanocrystal/Al2O3/IrOx memory structure have been investigated. The high-k nanocrystals can be formed after high temperature (>900oC) annealing process. The high-k nanocrystal memory devices with a small EOT of ~ 8 nm show a large hysteresis memory window of 3.8 V at a sweeping gate voltage of ±9V, 0.2s. A hysteresis memory window of 0.9 V has also been observed under a small sweeping gate voltage of ±7 V. A good uniformity of the high-k nanocrystal memory devices is also observed. A large memory window of >2V and a low charge loss of 14% are achieved after ~8x105s (9 days) of retention time owing to the charge confinement in the high-k nanocrystals.