A high- k Y2 O3 charge trapping layer for nonvolatile memory application

In this letter, a silicon-oxide-high- k -oxide-silicon memory structure using a high- k Y2 O3 film as the charge trapping layer is reported for nonvolatile memory application. From x-ray photoelectron spectroscopic analysis, we found that the Y2 O3 layer formed after annealing at 700 °C for 30 s. When using channel hot electron injection for charging and band-to-band hot hole for discharging, the high- k Y2 O3 memories exhibited large threshold voltage shifting (memory window of 2.3 V), excellent data retention (charge loss of 8% at room temperature), and good endurance characteristics (program/erase cycles up to 105) because of the higher probability for trapping the charge carrier due to the formation of a well-crystallized Y2 O3 structure.