Light emitting diode component

• US 10,461,230 B2
• Filed: 05/07/2018
• Issued: 10/29/2019
• Est. Priority Date: 04/25/2013
• Status: Active Grant

• Current Assignee: Lumileds LLC (Apollo Global Management, Inc.)
• Original Assignee: Koninklijke Philips N.V.
• Inventors: Lopez, Toni
• Primary Examiner(s): Gheyas, Syed I
• Application Number:
  US15/972,480
• Publication Number:
  US 20180254390A1
• Time in Patent Office: 540 Days
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/507 the elements being in intimate contact with parts other than the semiconductor body or integrated with parts other than the semiconductor body
• CPC Class Codes: H01L 33/58 Optical field-shaping elements

Abstract

The present invention relates to a light emitting diode component, comprising a light emitting semiconductor structure having a top surface, and a micro-optical multilayer structure arranged to guide light out from said light emitting semiconductor structure, said micro-optical multilayer structure comprising a plurality of layers, wherein an i+1:th layer is arranged on top an i:th layer in a sequence as seen from said semiconductor structure, wherein a refractive index, n_i, of the i:th layer is greater than a refractive index, n_i+l, of the i+1:th layer, and wherein a thickness of the i+1:th layer is greater than a thickness of the i:th layer. The present invention also relates to a light emitting diode comprising such a light emitting diode component.

Claims

1. A method, comprising:

providing a light emitting semiconductor structure grown on a growth substrate;

removing at least a portion of the growth substrate; and

forming a multilayer structure arranged to guide light out from a surface of the light emitting semiconductor structure, the multilayer structure covering the surface of the light emitting structure, the multilayer structure comprising a plurality of layers, wherein an i+1;

th layer is arranged on top an i;

th layer in a sequence as seen from the light emitting semiconductor structure, wherein a refractive index, n_i, of the i;

th layer is greater than a refractive index, n_i+1, of the i+1;

th layer, wherein the value of i is selected from the set of positive integers, wherein a thickness of the i+1;

th layer is greater than a thickness of the i;

th layer.

2. The method of claim 1, wherein the thicknesses of the i+1:

th layer and the i;

th layer are on the order of hundreds of microns.

3. The method of claim 1, wherein a thickness of the i:

th layer, t_i, is given by;

t_i=√

A/tan[sin {circumflex over ( 

)}(−

1)(n_(i+1)/n_i)]

wherein A is the top surface area of the multilayer structure.

4. The method of claim 1, further comprising attaching the light emitting semiconductor structure to a mount.

5. The method of claim 1, wherein removing at least a portion of the growth substrate comprises removing the entire growth substrate.

6. The method of claim 5, further comprising roughening or patterning a surface of the light emitting semiconductor structure exposed by removing the entire growth substrate.

7. The method of claim 5, wherein forming a multilayer structure comprises forming the multilayer structure on a surface of the light emitting semiconductor structure exposed by removing the entire growth substrate.

8. The method of claim 5, further comprising disposing a wavelength converting material on a surface of the light emitting semiconductor structure exposed by removing the entire growth substrate.

9. The method of claim 1, wherein removing at least a portion of the growth substrate comprises a technique selected from the group consisting of laser-assisted lift off, grinding, chemical-mechanical polishing, and wet etching.

10. The method of claim 1, further comprising forming a wavelength converting material over the light emitting semiconductor structure.

11. The method of claim 1, further comprising forming a reflective material on a side surface of the light emitting semiconductor structure.

12. The method of claim 1, further comprising forming a lens over the light emitting semiconductor structure.

13. The method of claim 3, wherein the thicknesses of the i+1:

th layer and the i;

th layer are on the order of hundreds of microns, and the top surface area is in the order of hundred thousand of square micron.

14. A device, comprising:

a light emitting semiconductor structure attached to a mount; and

a multilayer structure disposed over a surface of the light emitting semiconductor structure from which at least a portion of a growth substrate has been removed, the multilayer structure covering the surface of the light emitting structure, the multilayer structure comprising a plurality of layers, wherein an i+1;

th layer is arranged on top an i;

th layer in a sequence as seen from the semiconductor structure, wherein a refractive index, n_i, of the i;

th layer is greater than a refractive index, n_i+1, of the i+1;

th layer ,wherein the value of i is selected from the set of positive integers, wherein a thickness of the i+1;

th layer is greater than a thickness of the i;

th layer.

15. The device of claim 14, wherein the multilayer structure is disposed in direct contact with the surface of the light emitting semiconductor structure from which at least a portion of a growth substrate has been removed.

16. The device of claim 14, further comprising a wavelength converting material disposed between the multilayer structure and the surface of the light emitting semiconductor structure from which at least a portion of a growth substrate has been removed.

17. The device of claim 16, further comprising an additional multilayer structure, wherein the wavelength converting layer is arranged in-between the multilayer structure and the additional multilayer structure.

18. The device of claim 14, further comprising a lens disposed over the multilayer structure.

19. The device of claim 14, wherein a first layer, as seen from the light emitting semiconductor structure, of the multilayer structure has a refractive index equal to the refractive index of a top region of the light emitting semiconductor structure.

20. The device of claim 14, further comprising a side layer arranged adjacent to a side surface of the semiconductor structure.

21. The device of claim 20, wherein the side layer is selected from the group consisting of a wavelength converting material, a phosphor material, a quantum dot, a fluorescent dye, a light reflecting coating material, high reflectance metals, and high diffuse reflectance fluoropolymers.

22. The device of claim 14, wherein the thicknesses of the i+1:

th layer and the i;

th layer are on the order of hundreds of microns, and the multilayer structure has a top surface area is in the order of hundred thousand of square micron.