Gate structure, semiconductor memory device having the gate structure and methods of fabricating the same

摘要

A gate structure using nanodots as a trap site, a semiconductor device having the gate structure and methods of fabricating the same are provided. The gate structure may include a tunneling layer, a plurality of nanodots on the tunneling layer, and a control insulating layer including a high-k dielectric layer on the tunneling layer and the nanodots. A semiconductor memory device may further include a semiconductor substrate, the gate structure according to example embodiments on the semiconductor substrate and a first impurity region and a second impurity region in the semiconductor substrate, wherein the gate structure is in contact with the first and second impurity regions.