LIGHT EMITTING DEVICE AND MANUFACTURE METHOD THEREOF

• US 20140186979A1
• Filed: 11/18/2013
• Published: 07/03/2014
• Est. Priority Date: 02/03/2005
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: Epistar Corporation
• Inventors: TU, Chuan-Cheng, WU, Jen-Chau, SHIEH, Yuh-Ren, CHEN, Tzer-Perng, HSIEH, Min-Hsun
• Granted Patent: US 9,018,655 B2
• Time in Patent Office: Days
• US Class Current: 438/27
• CPC Class Codes: H01L 2224/13 of an individual bump connector
• CPC Class Codes: H01L 2224/131 with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/16227 the bump connector connecting to a bond pad of the item
• CPC Class Codes: H01L 2224/2929 with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/73204 the bump connector being embedded into the layer connector
• CPC Class Codes: H01L 2224/81005 being a temporary or sacrificial substrate
• CPC Class Codes: H01L 2224/83101 as prepeg comprising a layer connector, e.g. provided in an insulating plate member
• CPC Class Codes: H01L 2224/83104 by applying pressure, e.g. by injection
• CPC Class Codes: H01L 2224/83851 being an anisotropic conductive adhesive
• CPC Class Codes: H01L 24/13 of an individual bump connector
• CPC Class Codes: H01L 24/16 of an individual bump connector
• CPC Class Codes: H01L 24/32 of an individual layer connector
• CPC Class Codes: H01L 24/73 Means for bonding being of different types provided for in two or more of groups H01L24/10, H01L24/18, H01L24/26, H01L24/34, H01L24/42, H01L24/50, H01L24/63, H01L24/71
• CPC Class Codes: H01L 24/81 using a bump connector
• CPC Class Codes: H01L 24/83 using a layer connector
• CPC Class Codes: H01L 27/153 in a repetitive configuration, e.g. LED bars
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/0002 : Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/0781 : being an ohmic electrical conductor
• CPC Class Codes: H01L 33/0093 : Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/0095 : Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H01L 33/22 : Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/38 : with a particular shape
• CPC Class Codes: H01L 33/504 : Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/52 : Encapsulations

Abstract

The present disclosure provides a method for forming a light-emitting apparatus, comprising providing a first board having a plurality of first metal contacts, providing a substrate, forming a plurality of light-emitting stacks and trenches on the substrate, wherein the light-emitting stacks are apart from each other by the plurality of the trenches, bonding the light-emitting stacks to the first board, forming an encapsulating material commonly on the plurality of the light-emitting stacks, and cutting the first board and the encapsulating material to form a plurality of chip-scale LED units.

Claims

1. A method for forming a light-emitting apparatus, comprising:

providing a first board having a plurality of first metal contacts;

providing a substrate;

forming a plurality of light-emitting stacks and trenches on the substrate, wherein the light-emitting stacks are apart from each other by the plurality of the trenches;

bonding the light-emitting stacks to the first board;

forming an encapsulating material commonly on the plurality of the light-emitting stacks; and

cutting the first board and the encapsulating material to form a plurality of chip--scale LED units.

2. The method of claim 1, further comprising removing the substrate before forming the encapsulating material.

3. The method of claim 1, further comprising forming a plurality of metal layers on the light-emitting stacks for bonding to the first metal contacts.

4. The method of claim 1, further comprising forming an opaque layer in the trench and enclosing the light-emitting stacks for preventing the light emitted from neighboring light-emitting stacks from mutually interfering or crosstalk.

5. The method of claim 1, further comprising selectively forming a first wavelength converting material on a first light-emitting stack and configured to convert the light emitted from the first light-emitting stack to a first light, wherein the first light-emitting stack is one of the plurality of light-emitting stacks.

6. The method of claim 5, further comprising selectively forming a second wavelength converting material on a second light-emitting stack and configured to convert the light emitted from the second light-emitting stack to a second light, wherein the second light-emitting stack is one of the plurality of light-emitting stacks.

7. The method of claim 6, wherein the plurality of light-emitting stacks comprise a third light-emitting stack devoid of any wavelength converting material formed thereon, wherein the light emitted from the first, second, and third light-emitting stacks is a blue light, and wherein the first light is a green light, and the second light is a red light.

8. The method of claim 1, further comprising an opaque layer formed in the trenches, wherein the encapsulating material is on the trench and the opaque layer.

9. The method of claim 6, further comprising forming a dielectric layer in the trench and between the opaque layer and the light-emitting stacks.

10. The method of claim 3, further comprising patterning the metal layers to form an uneven surface on the metal layers.

11. The method of claim 1, further comprising removing the substrate to expose an exposed surface of the light-emitting stacks after bonding the light-emitting stacks to the first board and roughening the exposed surface of the light-emitting stacks.

12. The method of claim 1, further comprising forming a reflecting layer between the light-emitting stacks and the first board.

13. The method of claim 1, further comprising forming an underfill material substantially over the surface of the first board before bonding the light-emitting stacks to the first metal contacts.

14. The method of claim 13, wherein the underfill material is electrically conductive, and the light-emitting stacks is electrically connected with the first board through the underfill material.

15. The method of claim 1, wherein the first metal contacts extend from a top surface of the first board to a bottom surface of the first board.

16. The method of claim 1, further comprising providing a second board having a plurality of second metal contacts, and bonding the plurality of chip-scale LED units to the second metal contacts of the second board.

17. The method of claim 1, wherein the light-emitting stacks are apart from each other by a distance less than 25 microns.

18. The method of claim 1, wherein one of the chip-scale LED units has an area less than 0.36 mm².

19. The method of claim 1, wherein one of the chip-scale LED units comprises single light-emitting stack, and the ratio of the area of the chip-scale LED unit to the area of the light-emitting stack is equal to or greater than 9.

20. The method of claim 1, wherein one of the chip-scale LED units comprises a plurality of light-emitting stacks, and the ratio of the area of the chip-scale LED unit to the total area of the light-emitting stacks is smaller than 2.