Semiconductor device with fin and related methods
A semiconductor device may include a substrate, a fin above the substrate and having a channel region therein, and source and drain regions adjacent the channel region to generate shear and normal strain on the channel region. A semiconductor device may include a substrate, a fin above the substrate and having a channel region therein, source and drain regions adjacent the channel region, and a gate over the channel region. The fin may be canted with respect to the source and drain regions to generate shear and normal strain on the channel region.
1. A method, comprising:
forming a semiconductor fin over a dielectric layer that is over a top surface of a substrate, the semiconductor fin extending in a first direction;
forming a plurality of gate structures over the semiconductor fin, the plurality of gate structures extending in a second direction that is canted with respect to the first direction;
forming recesses on opposite sides of the plurality of gate structures, the recesses exposing the top surface of the substrate; and
epitaxially growing a semiconductor material in the recesses.
2. The method of claim 1 wherein the epitaxially growing the semiconductor material in the recesses comprises epitaxially growing the semiconductor material from top surface of the substrate and sidewall surfaces of remaining portions of the semiconductor fin.
3. The method of claim 1 wherein the forming the recesses comprises removing portions of the semiconductor fin and the dielectric layer on the opposite sides of the plurality of gate structures.
4. The method of claim 3 wherein the removing portions of the semiconductor fin and the dielectric layer on the opposite sides of the plurality of gate structures comprises etching the portions of the semiconductor fin and the dielectric layer on the opposite sides of the plurality of gate structures.
5. The method of claim 1 wherein the epitaxially growing the semiconductor material in the recesses comprises epitaxially growing silicon germanium in the recesses.
6. The method of claim 1 wherein the recesses expose sidewalls of remaining portions of the semiconductor fin and remaining portions of the dielectric layer.
7. A method, comprising:
forming a fin-shaped semiconductor structure over a substrate, the fin-shaped semiconductor structure oriented along a first direction;
forming a gate structure that interfaces the fin-shaped semiconductor structure at two or more surfaces of the fin-shaped semiconductor structure; and
forming a source or drain structure on a side of the gate structure, the source or drain structure interfacing with an edge surface of the fin-shaped semiconductor structure, the edge surface being at an oblique angle to the first direction.
8. The method of claim 7 wherein the forming the source or drain structure includes:
forming a recess in the fin-shaped semiconductor structure, the recess having a sidewall surface at the oblique angle to the first direction; and
epitaxially growing a semiconductor layer in the recess.
9. The method of claim 8 wherein the semiconductor layer is silicon germanium.
10. The method of claim 9 wherein the fin-shaped semiconductor structure is silicon.
11. The method of claim 7 wherein the oblique angle is in a range from 22.5 degrees to 67.5 degrees.
12. The method of claim 7 wherein the oblique angle is in a range from 40 degrees to 50 degrees.
13. The method of claim 8 wherein the forming the recess forms the recess through the fin-shaped semiconductor structure and exposes the substrate through the recess.
14. The method of claim 7 , comprising forming a dielectric layer over the substrate,
wherein the fin-shaped semiconductor structure is formed over the dielectric layer.
15. A method, comprising:
forming a plurality of semiconductor fin structures over a substrate, the plurality of semiconductor fin structures each oriented in a first direction;
forming a plurality of gate structures each overlapping the plurality of semiconductor fin structures, the plurality of gate structures each oriented along a second direction that is at an oblique angle to the first direction;
forming recesses in the plurality of semiconductor fin structures between the plurality of gate structures; and
forming source or drain structures in the recesses, the source or drain structures extending in the second direction.
16. The method of claim 15 wherein the oblique angle is in a range from 22.5 degrees to 67.5 degrees.
17. The method of claim 15 wherein the substrate is silicon.
18. The method of claim 15 wherein the forming the source or drain structures includes growing an epitaxial semiconductor layer in the recesses.
19. The method of claim 15 wherein the source or drain structures each contacts a respective one of the plurality of semiconductor fin structures at a surface along the second direction.
20. The method of claim 15 wherein the recesses are formed to reach the substrate.