Selective gallium nitride regrowth on (100) silicon
View Patent ↗A semiconductor structure including a (100) silicon substrate having a plurality openings located within the silicon substrate, wherein each opening exposes a surface of the silicon substrate having a (111) crystal plane. This structure further includes an epitaxial semiconductor material located on an uppermost surface of the (100) silicon substrate, and a gallium nitride material located adjacent to the surface of the silicon substrate having the (111) crystal plane and adjacent a portion of the epitaxial semiconductor material. The structure also includes at least one semiconductor device located upon and within the gallium nitride material and at least one other semiconductor device located upon and within the epitaxial semiconductor material.
1. A semiconductor structure comprising:
a (100) silicon substrate having a plurality openings located within the silicon substrate, wherein each opening exposes a surface of the silicon substrate having a (111) crystal plane;
an epitaxial semiconductor material located directly on an uppermost surface of said (100) silicon substrate;
a gallium nitride material located adjacent to the surface of the silicon substrate having the (111) crystal plane and adjacent a portion of said epitaxial semiconductor material, wherein said gallium nitride material has a bottommost surface that is located beneath a bottommost surface of said epitaxial semiconductor material and beneath said uppermost surface of said (100) silicon substrate; and
at least one semiconductor device located upon and within said gallium nitride material and at least one other semiconductor device located upon and within said epitaxial semiconductor material.
2. The semiconductor structure of claim 1 , further comprising an AlN buffer layer located between said portion of said epitaxial semiconductor material and said gallium nitride material.
3. The semiconductor structure of claim 1 , further comprising a dielectric spacer located between said portion of said epitaxial semiconductor material and said gallium nitride material.
4. The semiconductor structure of claim 3 , wherein a portion of said dielectric spacer is in contact with an AlN buffer layer present in each opening, said buffer layer is located between the surface of the silicon substrate having the (111) crystal plane and the gallium nitride material.
5. The semiconductor structure of claim 1 , further comprising a gap located between said portion of said epitaxial semiconductor material and said gallium nitride material.
6. The semiconductor structure of claim 1 , wherein said (100) silicon substrate comprises a bulk semiconductor material.
7. The semiconductor structure of claim 1 , wherein said (100) silicon substrate comprises a topmost layer of a silicon-on-insulator substrate.
8. The semiconductor structure of claim 1 , wherein said gallium nitride material is selected from GaN, GaAlN, GaInN and GaAlInN.
9. The semiconductor structure of claim 1 , wherein said gallium nitride material is single crystal and is of a single phase, wherein said single phase is a wurtzite phase.
10. The semiconductor structure of claim 1 , wherein each opening of said plurality of openings has an upper portion having a width that is larger than a width of a lower portion.
11. The semiconductor structure of claim 1 , wherein a portion of said gallium nitride material within each opening extends above a surface of the (100) silicon substrate having a non-(111) crystal plane.
12. The semiconductor structure of claim 1 , wherein said gallium nitride material consists essentially of GaN.
13. The semiconductor structure of claim 1 , wherein said epitaxial semiconductor material comprises silicon.
14. The semiconductor structure of claim 1 , wherein said epitaxial semiconductor material comprises a semiconductor material other than silicon.
15. The semiconductor structure of claim 1 , wherein said at least one semiconductor device located upon and within said gallium nitride material and said at least one other semiconductor device located upon and within said epitaxial semiconductor material each comprise a field effect transistor.
16. The semiconductor structure 1 , further comprising an interconnect located above said at least one semiconductor device located upon and within said gallium nitride material and at least one other semiconductor device located upon and within said epitaxial semiconductor material.