Group III-V substrate material with particular crystallographic features
A substrate including a body comprising a Group III-V material and having an upper surface, the body comprising an offcut angle defined between the upper surface and a crystallographic reference plane, and the body further having an offcut angle variation of not greater than about 0.6 degrees.
1. A method of forming a substrate comprising:
providing a body comprising a Group III-V material, the body having an upper surface and a rear surface opposite the upper surface; and
shaping the body to change a physical bow of the body and a crystallographic bow of the body, wherein shaping comprises applying an axial force to the body in a direction perpendicular to a plane defined by the upper surface.
2. The method of claim 1 , wherein the axial force is not greater than about 1000 N.
3. The method of claim 2 , wherein the axial force is applied preferentially to one of a center portion or peripheral portion of the body depending upon a curvature of the body.
4. The method of claim 1 , wherein shaping further comprises binding the body to a flattened position.
5. The method of claim 1 , wherein shaping comprises:
heating the body and a binding material to a temperature sufficient to change the binding material to a liquid phase; and
cooling the body after heating to solidify the binding material into a solid phase and bind the body to the platen.
6. The method of claim 1 , wherein shaping comprises reducing the bow by at least about 10% based on an equation ΔBow=[(h 1 −h 2 )/h 1 )], wherein h 1 is a bow of the body before shaping and h 2 is a bow of the wafer after shaping.
7. The method of claim 1 , wherein after shaping, the body comprises an offcut angle defined between the upper surface and a crystallographic reference plane, and wherein after shaping the body comprises an offcut angle variation (2β) is not greater than about 0.6 degrees (+/−0.3 degrees).
8. The method of claim 4 , wherein binding comprises attaching the body to a shaping platen while applying a force to the body to change the physical bow and crystallographic bow of the body.
9. The method of claim 4 , wherein binding comprises adhering the body to a shaping platen using a binding material.
10. The method of claim 5 , wherein the binding material comprises an organic material.
11. The method of claim 5 , wherein the binding material comprises a wax.
12. The method of claim 5 , wherein heating the body comprises heating at a temperature of at least about 40° C.
13. A method of forming a substrate comprising:
shaping a body comprising a Group III-V material to change a physical bow of the body and a crystallographic bow of the body, wherein the body has an upper surface and a rear surface opposite the upper surface, and wherein shaping comprises compressing the body.
14. The method of claim 13 , wherein compressing the body includes pressing the body between an upper platen coupled to an upper surface and a lower platen coupled to the rear surface.
15. The method of claim 14 , wherein shaping comprises adhering the body to a lower platen during compressing the body.
16. The method of claim 15 , wherein adhering comprises removably coupling the body to the lower platen.
17. The method of claim 15 , wherein adhering comprises placing an adhesive material on the rear surface of the body.
18. The method of claim 13 , wherein shaping comprises reducing the bow by at least about 10% based on an equation ΔBow=[(h 1 −h 2 )/h 1 )], wherein h 1 is a bow of the body before shaping and h 2 is a bow of the wafer after shaping.
19. The method of claim 13 , wherein after shaping, the body comprises an offcut angle defined between the upper surface and a crystallographic reference plane, the offcut angle (α) being not greater than about 2 degrees.
20. The method of claim 13 , wherein after shaping the body comprises an offcut angle variation (2β) not greater than about 0.5 degrees (+/−025 degrees).