A Novel Ion-Bombarded and Plasma-Passivated Charge Storage Layer for SONOS-Type Nonvolatile Memory

A novel technique combination of ion bombardment (IB) and NH3 plasma treatment (PT) has been presented to yield a highly effective charge storage layer for Si/SiO2/Si3N4/SiO2/Si (SONOS)-type nonvolatile memory applications. The IB technique creates additional trap sites within the charge storage layer strikingly to enhance the charge trapping/detrapping efficiency of the storage layer, and the NH3 PT passivates shallow trap sites significantly to improve reliability characteristics. The distribution of trap sites corresponding with various energy levels is clearly described by discharge-based multipulse analysis. As compared with the control sample (without IB and NH3 PT), the ion-bombarded and NH3-plasma-passivatedmemory device has faster program/erase speeds and larger memory window. In addition, the competent reliability properties of the ion-bombarded and NH3-plasma-passivated memory, such as good endurance, long data retention, and acceptable disturbance, were also demonstrated in this letter.