Methods and systems for gate dimension control in multi-gate structures for semiconductor devices
View Patent ↗Methods and systems are disclosed for gate dimension control in multi-gate structures for integrated circuit devices. Processing steps for formation of one or more subsequent gate structures are adjusted based upon dimensions determined for one or more previously formed gate structures. In this way, one or more features of the resulting multi-gate structures can be controlled with greater accuracy, and variations between a plurality of multi-gate structures can be reduced. Example multi-gate features and/or dimensions that can be controlled include overall gate length, overlap of gate structures, and/or any other desired features and/or dimensions of the multi-gate structures. Example multi-gate structures include multi-gate NVM (non-volatile memory) cells for NVM systems, such as for example, split-gate NVM cells having select gates (SGs) and control gates (CGs).
1. An integrated circuit device having a plurality of multi-gate structures, comprising:
a plurality of first gates for a plurality of multi-gate structures for an integrated circuit device; and
a plurality of second gates for the plurality of multi-gate structures;
wherein the plurality of multi-gate structures comprise at least one hundred or more multi-gate structures;
wherein overall gate lengths for the plurality of multi-gate structures vary by 10 percent or less;
wherein the multi-gate structures comprise multi-gate structures for multi-gate non-volatile memory (NVM) cells;
wherein the multi-gate NVM cells comprise split-gate NVM cells and each of the multi-gate structures comprises a select gate and a control gate;
wherein the overall gate lengths comprise combined gate lengths for the select gates and the control gates without including any gate overlaps;
wherein the overall gate length of the select gate and the control gate for each NVM cell is 280 to 320 nanometers; and
wherein an overlap of the control gate and the select gate for each NVM cell is 40 to 60 nanometers.
2. The integrated circuit device of claim 1 , wherein gate lengths for the first gates vary by more than 10 percent.
3. The integrated circuit device of claim 1 , wherein the multi-gate structures comprise one or more additional gates in addition to the first gates and the second gates.
4. The integrated circuit device of claim 1 , further comprising a charge storage layer between the select gates and the control gates for the split-gate NVM cells.
5. The integrated circuit device of claim 1 , wherein split-gate NVM cells have a device line size of about 50 nanometers or less.
6. The integrated circuit device of claim 1 , wherein the control gate overlaps the select gate for each NVM cell.