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 comprising:
forming a first set of trenches in a semiconductor material, wherein forming the first set of trenches comprises forming a plurality of first mandrels and forming first sidewall spacers on the first mandrels;
filling the first set of trenches with a first insulator material; and
forming a second set of trenches in the semiconductor material, self-aligned to and alternating with the first set of trenches, to form a plurality of fins,
wherein a pitch of the first set of trenches is approximately one-half a pitch of the plurality of first mandrels.
2. The method of claim 1 , wherein the plurality of first mandrels are formed on an insulator layer.
3. The method of claim 1 , wherein a pitch of the plurality of fins is approximately one-quarter a pitch of the plurality of first mandrels.
4. The method of claim 1 , further comprising:
filling the second set of trenches with a second insulator material; and
recessing the first and second insulator materials to partially expose fin sidewalls.
5. The method of claim 1 , wherein forming the first set of trenches further comprises:
removing the plurality of first mandrels; and
etching trenches through spaces between the first sidewall spacers.
6. The method of claim 1 , wherein forming the second set of trenches further comprises forming second sidewall spacers on second mandrels formed from the first insulator material.
7. The method of claim 1 , wherein the first insulator material is present when the second set of trenches is formed.
8. The method of claim 1 , wherein filling the first set of trenches further comprises depositing a flowable oxide followed by an anneal process.
9. The method of claim 1 , wherein filling the second set of trenches further comprises depositing a flowable oxide followed by an anneal process.
10. A method comprising:
forming a first set of trenches in a semiconductor material, wherein forming the first set of trenches comprises forming a plurality of first mandrels;
filling the first set of trenches with a first insulator material; and
forming a second set of trenches in the semiconductor material, self-aligned to and alternating with the first set of trenches, to form a plurality of fins with the first insulator material still present,
wherein a pitch of the first set of trenches is approximately one-half a pitch of the plurality of the first mandrels.
11. The method of claim 10 , wherein forming the first set of trenches further comprises forming first sidewall spacers on the plurality of first mandrels.
12. The method of claim 11 , wherein the plurality of first mandrels and the first sidewall spacers are formed on an insulator layer.
13. The method of claim 10 , wherein forming the second set of trenches further comprises forming second sidewall spacers on second mandrels formed from the first insulator material.
14. The method of claim 13 , wherein the second sidewall spacers are formed by ALD.
15. The method of claim 10 , wherein a pitch of the plurality of fins is approximately one-quarter a pitch of the plurality of first mandrels.
16. The method of claim 10 , further comprising:
filling the second set of trenches with a second insulator material; and
recessing the first and second insulator materials to partially expose fin sidewalls.
17. A method comprising:
forming a first set of trenches in a semiconductor material, wherein forming the first set of trenches comprises forming a plurality of first mandrels and forming first sidewall spacers on the first mandrels;
filling the first set of trenches with a first insulator material; and
forming a second set of trenches in the semiconductor material, self-aligned to and alternating with the first set of trenches, to form a plurality of fins,
wherein a pitch of the plurality of fins is approximately one-quarter a pitch of the plurality of first mandrels.
18. A method comprising:
forming a first set of trenches in a semiconductor material, wherein forming the first set of trenches comprises forming a plurality of first mandrels;
filling the first set of trenches with a first insulator material; and
forming a second set of trenches in the semiconductor material, self-aligned to and alternating with the first set of trenches, to form a plurality of fins with the first insulator material still present,
wherein a pitch of the plurality of fins is approximately one-quarter a pitch of the plurality of first mandrels.
19. A method comprising:
forming a first set of trenches in a semiconductor material, wherein forming the first set of trenches comprises forming a plurality of first mandrels and forming first sidewall spacers on the first mandrels, and wherein forming the first set of trenches comprises (i) removing the plurality of first mandrels and (ii) etching trenches through spaces between the first sidewall spacers;
filling the first set of trenches with a first insulator material; and
forming a second set of trenches in the semiconductor material, self-aligned to and alternating with the first set of trenches, to form a plurality of fins.