Multi-fin FINFET device including epitaxial growth barrier on outside surfaces of outermost fins and related methods
A multi-fin FINFET device may include a substrate and a plurality of semiconductor fins extending upwardly from the substrate and being spaced apart along the substrate. Each semiconductor fin may have opposing first and second ends and a medial portion therebetween, and outermost fins of the plurality of semiconductor fins may comprise an epitaxial growth barrier on outside surfaces thereof. The FINFET may further include at least one gate overlying the medial portions of the semiconductor fins, a plurality of raised epitaxial semiconductor source regions between the semiconductor fins adjacent the first ends thereof, and a plurality of raised epitaxial semiconductor drain regions between the semiconductor fins adjacent the second ends thereof.
1. A device, comprising:
a substrate;
a fin over the substrate, the fin having a first sidewall surface and a second sidewall surface opposite to the first sidewall surface, the second sidewall surface including an upper portion and a lower portion; and
an epitaxial growth barrier layer over the first sidewall surface, the lower portion of the second sidewall surface being free of the epitaxial growth barrier layer.
2. The device of claim 1 wherein the fin includes a top surface meeting the first sidewall surface and the second sidewall surface, and the epitaxial growth barrier layer is on the top surface of the fin.
3. The device of claim 1 wherein the epitaxial growth barrier layer is on the upper portion of the second sidewall surface.
4. The device of claim 1 , comprising an epitaxy layer on the lower portion of the second sidewall surface.
5. The device of claim 4 wherein the epitaxy layer includes a convex cross-section shape.
6. The device of claim 4 wherein the fin includes a top surface meeting the first sidewall surface and the second sidewall surface, and the epitaxy layer includes a top surface that is lower than the top surface of the fin with respect to the substrate.
7. The device of claim 1 wherein the epitaxial growth barrier layer is a compound including one or more of a semiconductor material of the first fin, carbon and fluorine.
8. The device of claim 1 wherein the fin includes a first dimension at a first point in a first direction transverse a surface of the substrate and a second dimension at a second point in the first direction, the second point being further from the substrate than the first point, the second dimension being smaller than the first dimension.
9. The device of claim 1 , comprising a gate structure over the fin.
10. A method, comprising:
forming a first fin and a second fin over a substrate, the first fin and the second fin parallel to one another, the first fin having a first sidewall surface and a second sidewall surface opposite to the first sidewall surface, the second sidewall surface including an upper portion and a lower portion, the second sidewall surface being closer to the second fin than the first sidewall surface; and
forming an epitaxial growth barrier layer on the first sidewall surface, the lower portion of the second sidewall surface being free of the epitaxial growth barrier layer.
11. The method of claim 10 wherein the forming the epitaxial growth barrier layer includes:
performing an ion implantation on the first fin at an angle offset from normal to the substrate.
12. The method of claim 11 wherein the second fin blocks ions of the ion implantation from reaching the lower portion of the second sidewall surface.
13. The method of claim 10 wherein the forming the first fin includes forming the first fin having a top surface meeting the first sidewall surface and the second sidewall surface, and wherein the forming the epitaxial growth barrier layer includes forming the epitaxial growth barrier layer on the top surface of the first fin.
14. The method of claim 10 wherein the forming the epitaxial growth barrier layer includes forming the epitaxial growth barrier layer on the upper portion of the second sidewall surface.
15. The method of claim 10 , comprising forming an epitaxy layer on the lower portion of the second sidewall surface of the first fin.
16. The method of claim 15 wherein the forming the epitaxy layer includes forming the epitaxy layer having a convex cross-section shape.
17. The method of claim 15 wherein the forming the epitaxial growth barrier layer includes forming the epitaxial growth barrier layer on the upper portion of the second sidewall surface; and
wherein epitaxial growth barrier layer prevents the epitaxy layer from being formed on the upper portion of the second sidewall surface.
18. The method of claim 15 , wherein the forming the first fin includes forming the first fin having a top surface meeting the first sidewall surface and the second sidewall surface; and
wherein the forming the epitaxy layer includes forming the epitaxy layer having a top surface that is lower than the top surface of the first fin with respect to the substrate.
19. A structure, comprising:
a substrate;
a fin over the substrate, the fin having a first sidewall surface and a second sidewall surface opposite to the first sidewall surface, the second sidewall surface including an upper portion and a lower portion;
an epitaxial growth barrier layer over the first sidewall surface, the lower portion of the second sidewall surface being free of the epitaxial growth barrier layer; and
a first conductive structure extending over a first end of the fin.
20. The structure of claim 19 , comprising a second conductive structure extending over a second end of the fin.