Fin cut during replacement gate formation
A method is presented for forming a semiconductor structure. The method includes forming a plurality of vertical fins over a semiconductor layer formed over a substrate, depositing an oxide over the plurality of fins, and applying a cutting mask over a portion of the plurality of fins. The method further includes removing the oxide from the exposed portion of the plurality of fins, depositing a replacement gate stack, and etching portions of the replacement gate stack to remove exposed fins, the exposed fins forming recesses within the semiconductor layer. The method further includes depositing a spacer over the exposed fins and the recesses formed by the removed fins. A portion of the plurality of fins are cut during etching of the replacement gate stack and a portion of the oxide is removed before deposition of the replacement gate stack.
1. A method of forming a semiconductor structure, the method comprising:
forming a plurality of vertical fins over a semiconductor layer formed over a substrate;
depositing an oxide over the plurality of fins;
applying a cutting mask over a portion of the plurality of fins;
removing the oxide from the exposed portion of the plurality of fins;
depositing a replacement gate stack; and
etching portions of the replacement gate stack to remove exposed fins to form recesses within the semiconductor layer.
2. The method of claim 1 , further comprising depositing a spacer over the exposed fins and the recesses formed by the removed fins.
3. The method of claim 2 , wherein the spacer is a non-conducting dielectric layer.
4. The method of claim 1 , wherein a portion of the plurality of fins are cut during etching of the replacement gate stack.
5. The method of claim 1 , wherein a portion of the oxide is removed before deposition of the replacement gate stack.
6. The method of claim 1 , wherein the replacement gate stack includes a dummy gate and a gate hard mask.
7. The method of claim 6 , wherein the dummy gate is formed of amorphous Si.
8. The method of claim 1 , wherein the cutting mask is an organic planarization layer (OPL).
9. The method of claim 1 , wherein each of the plurality of vertical fins is formed by Si.
10. The method of claim 1 , wherein each of the plurality of vertical fins is formed by SiGe.