Laser liftoff structure and related methods

• US 8,110,425 B2
• Filed: 03/20/2008
• Issued: 02/07/2012
• Est. Priority Date: 03/20/2007
• Status: Active Grant

• Current Assignee: Luminus Devices Incorporated (Sanan Optoelectronics Company Limited)
• Original Assignee: Luminus Devices Incorporated (Sanan Optoelectronics Company Limited)
• Inventors: Yun, Feng
• Primary Examiner(s): MULPURI, SAVITRI
• Application Number:
  US12/052,721
• Publication Number:
  US 20080274574A1
• Time in Patent Office: 1,419 Days
• Field of Search: 438/47
• US Class Current: 438/47
• CPC Class Codes: H01L 33/0075 comprising nitride compounds
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate

Abstract

Light-emitting devices, and related components, systems, and methods associated therewith are provided.

Claims

1. A method of making a light emitting device, the method comprising:

providing a first multi-layer stack, comprising

a substrate

a submount,

a wide bandgap buffer region between the substrate and the submount, wherein the buffer region includes a dislocation reduction region comprising a superlattice semiconductor structure; and

a sacrificial portion between the buffer region and the submount; and

exposing the sacrificial portion to electromagnetic radiation to at least partially decompose the sacrificial portion; and

removing the substrate and at least part of the buffer region from the first multi-layer stack to form a second multi-layer stack,

wherein the substrate and the buffer region are transparent to wavelengths of the electromagnetic radiation.

2. The method of claim 1, wherein the dislocation reduction region has a varying composition across a thickness of the region.

3. The method of claim 1, wherein the composition of at least one of the elements in the dislocation reduction region is graded across a thickness of the region.

4. The method of claim 1, wherein the superlattice semiconductor structure comprises an Al_xGa_1-xN/Al_yGa_1-yN superlattice.

5. The method of claim 1, wherein the electromagnetic radiation has a wavelength of smaller than 250 nm.

6. The method of claim 1, wherein the buffer region further comprises an AlN layer.

7. The method of claim 1, wherein the second multi-layer stack comprises the n-doped region at an upper surface of the second multi-layer stack.

8. The method of claim 1, wherein the multilayer stack comprises a light generating region.

9. The method of claim 1, wherein the sacrificial portion comprises a semiconductor material.

10. The method of claim 1, wherein the decomposing the sacrificial portion comprises forming a gas and a liquid.

11. The method of claim 1, wherein the substrate is formed of AlN.

12. The method of claim 1, wherein the first multi-layer stack includes an n-doped region formed directly on the buffer region.

13. The method of claim 12, wherein the n-doped region comprises the sacrificial portion.

14. The method of claim 12, wherein the n-doped region is less than 1000 nm.

15. The method of claim 12, wherein the n-doped region is less than 500 nm.

16. A method of making a light emitting device, the method comprising:

providing a first multi-layer stack, comprising;

a substrate;

a submount;

a wide bandgap buffer region between the substrate and the submount, wherein the buffer region includes a dislocation reduction region, the dislocation reduction region has a varying composition across a thickness of the region, and the composition of at least one of the elements in the dislocation reduction region is graded across a thickness of the region; and

a sacrificial portion between the buffer region and the submount; and

exposing the sacrificial portion to electromagnetic radiation to at least partially decompose the sacrificial portion; and

removing the substrate and at least part of the buffer region from the first multi-layer stack to form a second multi-layer stack,

wherein the substrate and the buffer region are transparent to wavelengths of the electromagnetic radiation; and

wherein the first multi-layer stack includes an n-doped region formed directly on the buffer region.

17. The method of claim 16, wherein the n-doped region comprises the sacrificial portion.

18. The method of claim 16, wherein the n-doped region is less than 1000 nm.

19. The method of claim 16, wherein the n-doped region is less than 500 nm.

20. The method of claim 16, wherein the electromagnetic radiation has a wavelength of smaller than 250 nm.

21. The method of claim 16, wherein the buffer region further comprises an AlN layer.

22. The method of claim 16, wherein the second multi-layer stack comprises the n-doped region at an upper surface of the second multi-layer stack.

23. The method of claim 16, wherein the multilayer stack comprises a light generating region.

24. The method of claim 16, wherein the sacrificial portion comprises a semiconductor material.

25. The method of claim 16, wherein the decomposing the sacrificial portion comprises forming a gas and a liquid.

26. The method of claim 16, wherein the substrate is formed of AlN.