Annealing oxide gate dielectric layers for replacement metal gate field effect transistors
AssigneeInternational Business Machines Corporation
InventorsUnoh Kwon, Wing L. Lai, Vijay Narayanan, Ravikumar Ramachandran, Shahab Siddiqui
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Abstract
A method of manufacturing a semiconductor structure by forming an oxide layer above a substrate; optionally annealing the oxide layer to densify the oxide layer; forming a first sacrificial gate above the substrate; removing the first dummy gate; optionally annealing the first gate oxide layer; and forming a first replacement metal gate above the gate oxide layer. In some embodiments selective nitridation may be performed during the annealing step.
Claims20
A method of manufacturing a semiconductor structure, the method comprising:
- forming an oxide layer above a substrate;
- annealing the oxide layer to densify the oxide layer;
- forming a first sacrificial gate comprising a first gate oxide layer and a first dummy gate above the substrate, wherein forming the first sacrificial gate comprises:
- depositing a dummy gate layer above the oxide layer;
- etching the dummy gate layer to form the first dummy gate;
- and
- etching the oxide layer to form the first gate oxide layer separating the first dummy gate from the substrate,
- removing the first dummy gate of the first sacrificial gate;
- annealing the first gate oxide layer;
- and
- forming a first replacement metal gate above the gate oxide layer.
A method of manufacturing a semiconductor structure, the method comprising:
- forming an oxide layer above a substrate;
- annealing the oxide layer;
- selectively nitriding a portion of the oxide layer to form an NFET oxide layer, wherein a PFET oxide layer comprises an un-nitrided portion of the oxide layer;
- depositing a dummy gate layer above the NFET oxide layer and the PFET oxide layer;
- etching the dummy gate layer to form a first dummy gate above the NFET oxide layer and a second dummy gate above the PFET oxide layer;
- etching the NFET oxide layer to form an NFET oxide gate layer between the first dummy gate and the substrate;
- etching the PFET oxide layer to form an PFET oxide gate layer between the second dummy gate and the substrate;
- and
- replacing the first dummy gate with a first replacement metal gate and the second dummy gate with a second replacement metal gate.
A method of manufacturing a semiconductor structure, the method comprising:
- forming an oxide layer above a substrate;
- depositing a dummy gate layer above the oxide layer;
- etching the dummy gate layer to form a first dummy gate and a second dummy gate above the oxide layer;
- etching the oxide layer to form a first oxide gate layer between the first dummy gate and the substrate and a second oxide gate layer between the second dummy gate and the substrate;
- removing the first dummy gate and the second dummy gate to expose the first oxide gate layer and the second oxide gate layer;
- annealing the first oxide gate layer and the second oxide gate layer;
- selectively nitriding the first oxide gate layer, so that the first gate oxide layer has a greater nitrogen concentration than the second gate oxide layer;
- and
- forming a first replacement metal gate above the first oxide gate layer and a second replacement metal gate above the second oxide gate layer.
Dependencies are inferred from the claim text.