Light-emitting devices including a nonperiodic pattern

• US 7,915,679 B2
• Filed: 09/27/2004
• Issued: 03/29/2011
• Est. Priority Date: 04/15/2003
• Status: Expired due to Fees

• Current Assignee: Luminus Devices Incorporated (Sanan Optoelectronics Company Limited)
• Original Assignee: Luminus Devices Incorporated (Sanan Optoelectronics Company Limited)
• Inventors: Erchak, Alexei A., Lidorikis, Elefterios, Luo, Chiyan
• Primary Examiner(s): Smith; Bradley K
• Assistant Examiner(s): Movva; Amar
• Application Number:
  US10/951,117
• Publication Number:
  US 20050051787A1
• Time in Patent Office: 2,374 Days
• Field of Search: 257/14, 257 79-103, 257/345, 257/E25.032
• US Class Current: 257/345
• CPC Class Codes: H01L 2933/0083 Periodic patterns for optical field-shaping in or on the semiconductor body or semiconductor body package, e.g. photonic bandgap structures
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H10K 50/85 Arrangements for extracting light from the devices
• CPC Class Codes: H10K 50/852 comprising a resonant cavity structure, e.g. Bragg reflector pair

Abstract

Light-emitting devices, and related components, systems and methods are disclosed. In some embodiments, the light-emitting devices include a multi-layer stack of materials. The stack of materials includes a light-generating region and a first layer supported by the light-generating region. The surface of the first layer is configured so that light generated by the light-generating region can emerge from the light-emitting device via the surface of the first layer. The surface has a dielectric function that varies spatially according to a nonperiodic pattern.

Claims

1. A light-emitting device, comprising:

a multi-layer stack of materials including a light-generating region and a first layer supported by the light-generating region, wherein;

a surface of the first layer is configured so that light generated by the light-generating region can emerge from the light-emitting device via the surface of the first layer; and

the surface has a dielectric function that varies spatially according to a nonperiodic pattern that is configured to increase light extraction from the device via the surface, the nonperiodic pattern is created by the configuration of a plurality of holes, wherein the holes are not encircled by other holes, wherein when viewed in a direction in which the holes extend from the surface into the first layer, the non-periodic pattern has no translational symmetry along the surface over a unit cell that has a length that is at least 50 times the peak wavelength of light generated by the light-generating region.

2. The light-emitting device of claim 1, wherein the nonperiodic pattern is selected from the group consisting of quasicrystalline patterns, Robinson patterns, and Amman patterns.

3. The light-emitting device of claim 1, wherein the multi-layer stack of materials comprises a multi-layer stack of semiconductor materials.

4. The light-emitting device of claim 3, wherein the first layer comprises a layer of n-doped semiconductor material, and the multi-layer stack further comprises a layer of p-doped semiconductor material.

5. The light-emitting device of claim 4, wherein the light-generating region is between the layer of n-doped semiconductor material and the layer of p-doped semiconductor material.

6. The light-emitting device of claim 5, further comprising a support that supports the multi-layer stack of materials.

7. The light-emitting device of claim 6, further comprising a layer of reflective material that is capable of reflecting at least about 50% of light generated by the light-generating region that impinges on the layer of reflective material, the layer of reflective material being between the support and the multi-layer stack of materials.

8. The light-emitting device of claim 7, wherein a distance between the layer of p-doped semiconductor material and the layer of reflective material is less than a distance between the layer of n-doped semiconductor material and the layer of reflective material.

9. The light-emitting device of claim 8, further comprising a p-ohmic contact layer between the layer of p-doped material and the layer of reflective material.

10. The light-emitting device of claim 1, further including a current-spreading layer between the first layer and the light-generating region.

11. The light-emitting device of claim 1, wherein the multi-layer stack of materials comprise semiconductor materials.

12. The light-emitting device of claim 11, wherein the semiconductor materials are selected from the group consisting of III-V semiconductor materials, organic semiconductor materials and silicon.

13. The light-emitting device of claim 1, wherein the pattern does not extend into the light-generating region.

14. The light-emitting device of claim 1, wherein the pattern does not extend beyond the first layer.

15. The light-emitting device of claim 1, wherein the pattern extends beyond the first layer.

16. The light-emitting device of claim 1, further comprising electrical contacts configured to inject current into the light-emitting device.

17. The light-emitting device of claim 16, wherein the electrical contacts are configured to vertically inject electrical current into the light-emitting device.

18. The light-emitting device of claim 1, wherein the pattern comprises a Penrose pattern.

19. The light-emitting device of claim 1, wherein the pattern is configured so that light emitted by the surface of the first layer has a spectrum of radiation modes, and the spectrum of radiation modes is substantially the same as a characteristic emission spectrum of the light-generating region.

20. The light-emitting device of claim 1, wherein the light-emitting device is selected from the group consisting of light-emitting diodes, lasers, optical amplifiers, and combinations thereof.

21. The light-emitting device of claim 1, wherein the light-emitting device comprises a light emitting diode.

22. The light-emitting device of claim 1, wherein the light-emitting device is selected from the group consisting of OLEDs, flat surface-emitting LEDs, HBLEDs, and combinations thereof.

23. The light-emitting device of claim 1, wherein the holes in the surface of the first layer have a size of less than about λ

/5, where λ

is a wavelength of light that can be generated by the light-generating region and that can emerge from the light-emitting device via the surface of the first layer.

24. The light-emitting device of claim 1, wherein a majority of the holes have substantially the same size.

25. The light-emitting device of claim 1, wherein a majority of nearest neighbor distances between the holes are substantially the same.

26. The light-emitting device of claim 1, wherein the pattern has in-plane symmetry.

27. The light-emitting device of claim 1, wherein the pattern has in-plane rotational symmetry.