Integration technique using thermal oxide select gate dielectric for select gate and replacement gate for logic

摘要

A control gate overlying a charge storage layer is formed. A thermally-grown oxygen-containing layer is formed over the control gate. A polysilicon layer is formed over the oxygen-containing layer and planarized. A first masking layer is formed defining a select gate location laterally adjacent the control gate and a second masking layer is formed defining a logic gate location. Exposed portions of the polysilicon layer are removed such that a select gate remains at the select gate location and a polysilicon portion remains at the logic gate location. A dielectric layer is formed around the select and control gates and polysilicon portion. The polysilicon portion is removed to result in an opening in the dielectric. A high-k gate dielectric and logic gate are formed in the opening.