Selective area growth of semiconductors using patterned sol-gel materials
Systems and methods for growing semiconductor materials on substrates by using patterned sol-gel materials are provided. According to a first aspect of the invention, a method includes forming a pattern of a sol-gel material on a first region of substrate, and depositing a semiconductor material on a second region of the substrate by selective area growth. The second region is adjacent to the first region.
1. A method comprising:
first forming a protective layer on a first region and a second region of a substrate; and further comprising the additional steps of forming a pattern of a sol-gel material on the first region of the substrate; and
then removing the protective layer from the second region of the substrate; and
then depositing a semiconductor material on the second region of the substrate by selective area growth comprising nucleating the semiconductor material at a growth rate between 0.5 and 2.0 microns per hour and a V/III ratio between 10 and 250, wherein the second region is adjacent to the first region; and
wherein the semiconductor material and the substrate are lattice mismatched.
2. The method according to claim 1 , wherein the depositing of the semiconductor material further comprises:
after the nucleating of the semiconductor material, increasing a temperature of the substrate; and
forming a condensed film of the semiconductor material within the second region.
3. The method according to claim 2 , further comprising:
after the depositing of the semiconductor material on the second region, forming a continuous film of another semiconductor material, such that the continuous film extends over the first region and the second region, by lateral overgrowth of the another semiconductor material.
4. The method according to claim 3 , wherein the forming of the continuous film of the semiconductor material comprises:
growing the semiconductor material at a growth rate between 1 and 20 microns per hour and a V/III ratio between 100 and 500.
5. The method according to claim 2 , wherein the semiconductor material is deposited and the condensed film is formed by chemical vapor deposition.
6. The method according to claim 5 , wherein the semiconductor material is deposited and the film is formed by metalorganic chemical vapor deposition.
7. The method according to claim 1 , wherein the forming of the pattern of the sol-gel material comprises:
coating the sol-gel material onto the substrate;
stamping the sol-gel material with a polymer stamp; and
annealing the sol-gel material.
8. The method according to claim 1 , wherein the semiconductor material and the substrate are different materials.
9. The method according to claim 1 , wherein the semiconductor material comprises a III-V material.
10. The method according to claim 9 , wherein the semiconductor material comprises GaAs.
11. The method according to claim 9 , wherein the substrate comprises Si.
12. The method according to claim 1 , wherein the protective layer is a passivating layer.
13. The method according to claim 1 , further comprising:
after the forming of the pattern of the sol-gel material, increasing a density of the sol-gel material by heating the sol-gel material.
14. The method according to claim 1 , further comprising:
after the forming of the pattern of the sol-gel material, performing a dilute HF etch to remove native oxide from the sol-gel material.
15. The method according to claim 1 , wherein the semiconductor material is uncatalyzed.