Hybrid charge trap memory device with TaN nanocrystals formed by phase separation methods

Hybrid charge trapping layer consisting of TaN nanocrystals (NCs) and silicon nitride (SiN) has been fabricated and characterized for silicon-oxide-nitride-oxide-silicon (SONOS) type nonvolatile memory device. After annealing at 900degC, TaN NCs with average sizes of 3.5nm were formed by the phase separation method. Compared with a control sample without NC, memory devices with TaN NCs exhibit superior memory characteristics. The improvement can be explained by the formation of high density TaN NCs with a deeper trap energy level.