Patent ID: 7405119

Claim:
A method of manufacturing a semiconductor device, comprising: forming a gate stack on a substrate, the gate stack having a sidewall; forming an oxide-nitride-oxide stack over the gate stack and along the sidewall; etching the oxide-nitride-oxide stack to form an oxide-nitride-oxide storage film structure having a generally L-shaped cross-section with a vertical portion along at least part of the gate stack sidewall and a horizontal portion along the substrate; forming a logic oxide spacer layer over the gate stack and the oxide-nitride-oxide storage film structure, such that a nitride portion of the oxide-nitride-oxide storage film structure is enclosed in oxide material of the oxide-nitride-oxide storage film structure and of the logic oxide spacer layer; forming a nitride spacer material over the gate stack, the oxide-nitride-oxide storage film structure, and the logic oxide spacer layer; etching the nitride spacer material to form a nitride spacer adjacent to the gate stack and at least partially over the oxide-nitride-oxide storage film structure and the logic oxide spacer layer; and forming a source/drain region in the substrate and directly adjacent the nitride spacer.