Structure and method for a sidewall SONOS memory device

A method of manufacturing a semiconductor memory device using a sub-0.130 micron manufacturing process, comprising:

• forming a gate stack on a substrate, the gate stack having a sidewall and the gate stack having a gate width of about 130 nanometers or less;
• 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.

A method of manufacturing a non-volatile memory, comprising:

• forming a gate stack directly over a substrate, the gate stack comprising a sidewall;
• forming a tunneling oxide layer over the substrate;
• forming a silicon nitride layer directly over the tunneling oxide layer;
• forming a sacrificial oxide layer directly over the silicon nitride layer;
• removing portions of the tunneling oxide layer;
• removing portions of the silicon nitride layer;
• removing portions of the sacrificial oxide layer to form an oxide-nitride-oxide structure, wherein a remaining portion of the silicon nitride layer in the oxide-nitride-oxide structure is a storage film;
• forming a logic oxide spacer material over the substrate;
• forming a silicon nitride spacer material directly over the logic oxide spacer material;
• removing portions of the logic oxide spacer material and portions of the silicon nitride spacer material to form a silicon nitride spacer adjacent to the sidewall;
• wherein a first portion of the oxide-nitride-oxide structure is directly adjacent and substantially aligned with the sidewall of the gate stack and a second portion of the oxide-nitride-oxide structure is directly adjacent and substantially aligned with a channel region in the substrate, wherein the channel region in the substrate is adjacent the gate stack, and wherein the storage film is encapsulated by oxide materials of the oxide-nitride-oxide structure and of the logic oxide spacer material;
• and
• forming a source/drain region in the substrate and directly adjacent the silicon nitride spacer.