FinFET devices
FinFET devices and processes to prevent fin or gate collapse (e.g., flopover) in finFET devices are provided. The method includes forming a first set of trenches in a semiconductor material and filling the first set of trenches with insulator material. The method further includes forming a second set of trenches in the semiconductor material, alternating with the first set of trenches that are filled. The second set of trenches form semiconductor structures which have a dimension of fin structures. The method further includes filling the second set of trenches with insulator material. The method further includes recessing the insulator material within the first set of trenches and the second set of trenches to form the fin structures.
1. A method of forming a semiconductor structure comprising:
forming a first etch mask above a substrate;
etching a plurality of first trenches in the substrate using the first etch mask;
filling the plurality of first trenches with first trench-filling materials, wherein:
the first trench-filing materials comprise a first liner disposed on opposite sidewalls of the plurality of first trenches; and
lower portions of the plurality of first trenches comprise a first conductive material;
removing the first etch mask to expose protrusions formed by the first trench-filing materials filing the plurality of first trenches;
subsequent to removing the first etch mask, forming spacers on sidewalls of the protrusions; and
etching a plurality of second trenches in the substrate using the spacers and the protrusions as a second etch mask, wherein the plurality of second trenches are interleaved with the plurality of first trenches.
2. The method of claim 1 , wherein regions between adjacent first and second trenches comprise silicon.
3. The method of claim 1 , wherein:
the first trench-filling materials further comprise a dielectric material; and
upper portions of the plurality of first trenches comprise the dielectric material.
4. The method of claim 1 , further comprising:
filing the plurality of second trenches with second trench-filling materials, wherein the second trench-filing materials comprise a second liner disposed on opposite sidewalls of the plurality of second trenches.
5. The method of claim 4 , wherein:
the second trench-filling materials further comprise a second conductive material; and
lower portions of the plurality of second trenches comprise the second conductive material.
6. The method of claim 5 , wherein:
the first trench-filling materials further comprise a first conductive material;
lower portions of the plurality of first trenches comprise the first conductive material; and
the first conductive material and the second conductive material comprise source/drain regions.
7. The method of claim 5 , wherein:
the first trench-filling materials further comprise a first conductive material;
lower portions of the plurality of first trenches comprise the first conductive material;
the first conductive material comprises a first semiconductor material; and
the second conductive material comprises a second semiconductor material different than the first semiconductor material.
8. The method of claim 5 , wherein:
the first trench-filling materials further comprise a first conductive material;
lower portions of the plurality of first trenches comprise the first conductive material; and
the first conductive material and the second conductive material comprise a same semiconductor material.
9. The method of claim 8 , wherein the first conductive material and the second conductive material comprise different dopants.
10. The method of claim 4 , wherein:
the second trench-filling materials further comprise a dielectric material; and
upper portions of the plurality of second trenches comprise the dielectric material.
11. The method of claim 4 , wherein:
regions between adjacent first and second trenches comprise dummy gates; and
the first liner and the second liner define boundaries of the dummy gates.
12. The method of claim 1 , wherein regions between adjacent first and second trenches comprise dummy gates.
13. The method of claim 12 , wherein the dummy gates comprise silicon.
14. The method of claim 12 , wherein the first liner defines boundaries of the dummy gates.
15. The method of claim 1 , wherein forming the first etch mask comprises:
forming a plurality of mandrels;
forming spacers on sidewalls of the mandrels; and
removing the plurality of mandrels.
16. The method of claim 15 , wherein a pitch of the plurality of first trenches is approximately one-half of a pitch of the plurality of mandrels.
17. The method of claim 15 , wherein a pitch of the plurality of first trenches is approximately 25 nm.
18. The method of claim 1 , wherein the first liner comprises SiOCN or SiCBN.