Method of making a dielectric for an integrated circuit

摘要

A composite 3-layer gate dielectric is disclosed. The upper and lower layers have a concentration of nitrogen atoms, while the middle layer has very few nitrogen atoms. The presence of the nitrogen atoms in the top sublayers provides resistance to boron diffusion from the top conductive layer and plasma damage during polysilicon gate stack formation and the presence of nitrogen in the bottom sublayer near the silicon-dielectric interface improves wearout, endurance, resistance to current stress and electron traps.