Semipolar or nonpolar group III-nitride substrates
Aspects of the disclosure provide for mechanisms for producing group III-nitride substrates. In accordance with some embodiments, a method for producing a group III-nitride substrate is provided. The method may include: forming, on a growth template, an epitaxial layer of a group III-nitride material comprising a surface with a first crystallographic orientation, wherein the first crystallographic orientation comprises a semipolar orientation or a nonpolar orientation; and separating the epitaxial layer of the group III-nitride material from the growth template to produce the group III-nitride substrate, wherein the growth template comprises a semiconductor layer of the group III-nitride material. The group III-nitride material may include gallium.
1. A method, comprising:
forming, on a growth template, an epitaxial layer of a group III-nitride material comprising a surface with a first crystallographic orientation, wherein the first crystallographic orientation comprises a semipolar orientation or a nonpolar orientation; and
separating the epitaxial layer of the group III-nitride material from the growth template to produce a group III-nitride substrate comprising the epitaxial layer of the group III-nitride material, wherein the growth template comprises a semiconductor layer of the group III-nitride material, and wherein the size of the epitaxial layer separated from the growth template is substantially the same as the size of the growth template.
2. The method of claim 1 , wherein the epitaxial layer of the group III-nitride material is free of stacking faults.
3. The method of claim 1 , wherein forming the epitaxial layer of the group III-nitride material comprises growing the group III-nitride material to a thickness greater than 100 microns.
4. The method of claim 1 , wherein the group III-nitride material comprises gallium.
5. The method of claim 1 , wherein the semiconductor layer is free of stacking faults.
6. The method of claim 1 , wherein forming, on the growth template, the epitaxial layer of the group III-nitride material comprises growing the group III-nitride material utilizing at least one of a hydride vapor phase epitaxy (HVPE) process, a molecular beam epitaxy (MBE) process, or a metalorganic chemical vapor deposition (MOCVD) process.
7. The method of claim 1 , wherein the epitaxial layer of the group III-nitride material is separated from the growth template along a longitudinal direction of the growth template.
8. The method of claim 1 , wherein growing the epitaxial layer of the group III-nitride material comprises growing the group III-nitride material on a process surface of the growth template, and wherein separating the epitaxial layer of the group III-nitride material from the growth template comprises separating the surface of the epitaxial layer from the process surface of the growth template.
9. The method of claim 8 , wherein the process surface of the growth template comprises a facet with the first crystallographic orientation.
10. The method of claim 8 , further comprising growing the semiconductor layer of the group III-nitride material on a foreign substrate, wherein a substrate surface of the foreign substrate is approximately parallel to a crystallographic plane of the foreign substrate with a second crystallographic orientation, and wherein the substrate surface of the foreign substrate is approximately parallel to the process surface of the growth template.
11. The method of claim 10 , wherein the foreign substrate comprises sapphire or silicon.
12. The method of claim 11 , wherein the first crystallographic orientation comprises (20 2 1), and wherein the second crystallographic orientation comprises (22 4 3).
13. The method of claim 10 , wherein growing the semiconductor layer further comprises removing stacking faults from at least one region of the semiconductor layer.
14. The method of claim 10 , further comprising:
growing a first facet of the semiconductor layer at a first growth rate, wherein the first facet has a crystallographic orientation associated with stacking faults; and
growing a second facet of the semiconductor layer at a second growth rate, wherein the second growth rate is greater than the first growth rate.
15. The method of claim 14 , further comprising doping the semiconductor layer with a dopant to control the first growth rate.
16. The method of claim 1 , wherein the semiconductor layer comprises an epitaxial layer comprising the group III-nitride material of the first crystallographic orientation.
17. The method of claim 16 , wherein the first crystallographic orientation comprises at least one of (20 2 1), (20 21 ), (30 3 1), (30 31 ), (10 1 1), (11 2 2), (11 2 0), or (10 1 0).
18. The method of claim 17 , wherein separating the epitaxial layer of the group III-nitride material from the growth template to produce the group III-nitride substrate comprising the epitaxial layer of the group III-nitride material comprises separating the epitaxial layer of the group III-nitride material from the growth template along an interface between the epitaxial layer of the group III-nitride material and the growth template, wherein the interface is defined by a surface of the growth template and a surface of the epitaxial layer, and wherein the surface of the epitaxial layer is approximately parallel to a crystallographic plane with the first crystallographic orientation.
19. The method of claim 18 , wherein the surface of the growth template is approximately parallel to the crystallographic plane with the first crystallographic orientation.
20. The method of claim 1 , wherein a diameter of the epitaxial layer separated from the growth template is substantially the same as a diameter of the growth template.