Metal-oxide-high- k -oxide-silicon memory structure using an Yb ₂O₃ charge trapping layer

In this letter, we proposed a metal-oxide-high- k -oxide-silicon (MOHOS)-type memory structure using a high- k Yb₂O₃ charge trapping layer for flash memory applications. When using Fowler-Nordheim for charging and discharging, the high- k Yb₂O₃ MOHOS-type memories that had been annealed at 800 °C exhibited large threshold voltage shifting (memory window of ∼2.2 V) and excellent data retention (charge loss of ∼6% measured time up to 104 s and at room temperature) because of the higher probability for trapping the charge carrier due to the formation of the Yb-silicate layer and the smooth surface roughness.