LIGHT EMITTING DEVICE AND METHOD FOR MANUFACTURING THE SAME

• US 20190319169A1
• Filed: 06/26/2019
• Published: 10/17/2019
• Est. Priority Date: 08/11/2017
• Status: Active Grant

• Current Assignee: Xiamen San'An Optoelectronics Co.Ltd. (Sanan Optoelectronics Company Limited)
• Original Assignee: Xiamen San'An Optoelectronics Co.Ltd. (Sanan Optoelectronics Company Limited)
• Inventors: HUANG, Senpeng, LIN, Zhen-duan, WONG, Weng-Tack, SHI, Junpeng, CHEN, Shunyi, CHAO, Chih-Wei, HSU, Chen-ke
• Granted Patent: US 11,005,008 B2
• Time in Patent Office: Days
• CPC Class Codes: H01L 2224/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 2933/005 relating to encapsulations
• CPC Class Codes: H01L 2933/0058 relating to optical field-shaping elements
• CPC Class Codes: H01L 33/0041 characterised by field-effect operation
• CPC Class Codes: H01L 33/005 Processes
• CPC Class Codes: H01L 33/0058 comprising amorphous semiconductors
• 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 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• CPC Class Codes: H01L 33/50 Wavelength conversion elements
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

A light emitting device includes an LED chip, a light-transmissible member and a light-reflecting member. The LED chip has a plurality of interconnecting side surfaces having a roughened structure and a plurality of corners. The light-transmissible member covers the side surfaces and the corners and includes a light-transmissible material layer having a breadth value W(A) of a viscosity coefficient (A) range of the light-transmissible material, which satisfies a relation of W(A)∝B*D/C: where B represents a thickness of the light-transmissible material layer, represents a thickness of the LED chip measured from the first surface to the second surface, and D represents a roughness of the roughened structure. A method for manufacturing the light emitting device is also provided.

Claims

1. A light emitting device, comprising:

a light emitting diode (LED) chip having a first surface, a second surface opposite to said first surface, two electrodes disposed on said second surface, a plurality of interconnecting side surfaces each connected between said first surface and said second surface, and a plurality of corners, each of said corners being correspondingly defined by adjacent two of said side surfaces and said second surface, said side surfaces having a roughened structure;

a light-transmissible member covering said side surfaces and said corners, and being made from a light-transmissible material layer; and

a light-reflecting member surrounding said light-transmissible member,

wherein sad light-transmissible material layer has a breadth value (W(A)) of a viscosity coefficient (A) range defined by a difference between upper and lower limits of the viscosity coefficient (A) range of the light-transmissible layer, the breadth value satisfying a relation W(A)∝

B*D/C, where B represents a thickness of said light-transmissible material layer, C represents a thickness of said LED chip measured from said first surface to said second surface of said LED chip, and D represents a roughness of said roughened structure of said side surfaces of said LED chip.

2. The light emitting device of claim 1, wherein the thickness (B) of said light-transmissible material layer ranges from 10 μ

m to 60 μ

m.

3. The light emitting device of claim 1, wherein the thickness (C) of said LED chip ranges from 150 μ

m to 200 μ

m.

4. The light emitting device of claim 1, wherein the roughness (D) of said roughened structure ranges from 0.01 μ

m to 2 μ

m.

5. The light emitting device of claim 1, wherein said roughened structure has one of a periodic arrangement and a non-periodic arrangement.

6. The light emitting device of claim 1, wherein said roughened structure is formed by one of stealth dicing and surface modification.

7. The light emitting device of claim 6, wherein said roughened structure is formed by the stealth dicing with a focused laser beam at different focusing depths, the focusing depths being spaced apart from one another by a spacing ranging from 30 μ

m to 80 μ

m.

8. The light emitting device of claim 6, wherein the surface modification is selected from spraying with particles, bonding with particles, and deposition with particles.

9. The light emitting device of claim 1, further comprising a wavelength conversion member disposed on said first surface of said LED chip, said light-transmissible member and said light-reflecting member.

10. A method for manufacturing a light emitting device, comprising:

providing at least one light emitting diode (LED) chip having opposite first and second surfaces, two electrodes disposed on the second surface, a plurality of interconnecting side surfaces formed with a roughened structure and each connected between the first and second surfaces, and a plurality of corners, each of the corners being correspondingly defined by adjacent two of the side surfaces and the second surface;

forming a light-transmissible material layer on a wavelength conversion member;

attaching the at least one LED chip to the wavelength conversion member and the light-transmissible material layer with the first surface of the LED chip attached to the wavelength conversion member and with the side surfaces and the corners attached to the light-transmissible material layer;

curing the light-transmissible material layer to form a light-transmissible member that covers the side surfaces and the corners; and

surroundingly forming a light-reflecting member on the light-transmissible member;

wherein the light-transmissible material layer has a breadth value (W(A)) of a viscosity coefficient (A) range defined by a difference between upper and lower limits of the viscosity coefficient (A) range of the light-transmissible layer, the breadth value satisfying relation of W(A)∝

B*D/C, where B represents a thickness of the light-transmissible material layer measured from the wavelength conversion member, C represents a thickness of the LED chip measured from the first surface to the second surface of the LED chip, and D represents a roughness of the roughened structure of the side surfaces of the LED chip.

11. The method of claim 10, wherein the provision of the at least one LED chip includes providing a plurality of the LED chips, the method further comprising cutting the light-reflecting member and the wavelength conversion member among the LED chips.

12. The method of claim 10, wherein the viscosity coefficient (A) range of the light-transmissible material layer ranges between 1000 mPa·

s and 6000 mPa·

s.

13. The method of claim 10, wherein the curing of the light-transmissible material layer is performed by stepwise heating.

14. The method of claim 13, wherein the stepwise heating includes heating at 50°

C. for 15 minutes, followed by heating at 70°

C. for 15 minutes, and then heating at 150°

C. for 30 minutes.

15. The method of claim 10, wherein the curing of the light-transmissible material layer is performed by controlling the viscosity coefficient (A) range of the light-transmissible material layer to be within 1000 mPa·

s to 1500 mPa·

s for 10 to 60 minutes.

16. The method of claim 10, wherein the thickness (B) of the light-transmissible material layer ranges from 10 μ

m to 60 μ

m.

17. The method of claim 10, wherein the thickness (C) of the LED chip ranges from 150 μ

m to 200 μ

m.

18. The method of claim 10, wherein the roughness (D) of the roughened structure ranges from 0.01 μ

m to 2 μ

m.

19. The method of claim 10, wherein the roughened structure has one of a periodic arrangement and a non-periodic arrangement.

20. The method of claim 10, wherein the provision of the at least one light emitting diode (LED) chip includes forming the roughened structure by one of stealth dicing and surface modification.