Light emitting diode package structure and fabrication method

• US 9,966,514 B2
• Filed: 06/24/2016
• Issued: 05/08/2018
• Est. Priority Date: 07/02/2015
• Status: Active Grant

• Current Assignee: Quanzhou Sanan Semiconductor Technology Co., Ltd. (Sanan Optoelectronics Company Limited)
• Original Assignee: Xiamen Sanan Optoelectronics Technology Company Limited (Sanan Optoelectronics Company Limited)
• Inventors: Hsu, Chen-Ke, Shi, Junpeng, Cai, Pei-Song, Lin, Zhenduan, Huang, Hao, Liao, Chenjie, Chao, Chih-Wei, Lin, Qiuxia
• Primary Examiner(s): Geyer, Scott B
• Application Number:
  US15/192,993
• Publication Number:
  US 20170005245A1
• Time in Patent Office: 683 Days
• CPC Class Codes: H01L 2224/04105 Bonding areas formed on an encapsulation of the semiconductor or solid-state body, e.g. bonding areas on chip-scale packages
• CPC Class Codes: H01L 2224/19 Manufacturing methods of high density interconnect preforms
• CPC Class Codes: H01L 2924/18162 of a chip with build-up interconnect
• CPC Class Codes: H01L 2933/0016 relating to electrodes
• CPC Class Codes: H01L 2933/0033 relating to semiconductor body packages
• 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 2933/0066 relating to arrangements for conducting electric current to or from the semiconductor body
• CPC Class Codes: H01L 2933/0091 Scattering means in or on the semiconductor body or semiconductor body package H01L33/22 takes precedence
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• 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 33/508 having a non-uniform spatial arrangement or non-uniform concentration, e.g. patterned wavelength conversion layer, wavelength conversion layer with a concentration gradient of the wavelength conversion material
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls

Abstract

A light emitting diode package structure allows for an improved light-emitting efficiency by including a first reflecting material layer with through holes; a flip chip on the first reflecting material layer, with the electrodes inlaid in the through holes of the first reflecting material layer; a first transparent material layer surrounding the side surface of the flip chip except the electrodes; and a second reflecting material layer surrounding the first transparent material layer. An interface between the first transparent material layer and the reflecting material layer is an inclined plane, an arc plane, or an irregular shape, to thereby facilitate upward light reflection of the flip chip. A wavelength conversion material layer is over the first reflecting material layer, the flip chip, and the second reflecting material layer.

Claims

1. A light emitting diode package structure, comprising:

a first reflecting material layer comprising a reflective glue with through holes;

a flip chip over the first reflecting material layer, with electrodes inlaid in the through holes of the first reflecting material layer;

a first transparent material layer comprising a transparent glue surrounding a side surface of the flip chip other than the electrodes;

a second reflecting material layer comprising a reflective glue surrounding the first transparent material layer, wherein an interface between the first transparent material layer and the second reflecting material layer is an inclined plane, an arc plane, or an irregular shape, to thereby facilitate upward light reflection of the flip chip; and

a wavelength conversion material layer comprising a fluorescent material.

2. The light emitting diode package structure of claim 1, wherein:

an upper surface of the second reflecting material layer is flush with upper surfaces of the first transparent material layer and the flip chip, and makes the upper surfaces into a co-plane.

3. The light emitting diode package structure of claim 2, wherein:

a selective optical film is arranged on the co-plane such that the selective optical film is between the co-plane and the wavelength conversion material layer.

4. The light emitting diode package structure of claim 3, wherein:

the selective optical film is configured to transmit blue light and reflect green light, yellow light, and red light.

5. The light emitting diode package structure of claim 1, wherein:

an inner edge of a bottom of the second reflecting material layer is in contact with a side surface of the flip chip.

6. The light emitting diode package structure of claim 1, wherein:

an inner edge of a bottom of the second reflecting material layer has a gap from a side surface of the flip chip.

7. The light emitting diode package structure of claim 1, wherein:

the first transparent material layer does not contain a wavelength conversion material.

8. The light emitting diode package structure of claim 1, wherein:

the first transparent material layer contains a wavelength conversion material.

9. The light emitting diode package structure of claim 1, wherein:

an interface between the first transparent material layer and the second reflecting material layer is an inclined plane, an arc plane, or an irregular shape.

10. The light emitting diode package structure of claim 1, wherein:

an optical reflecting layer is inserted at an interface between the first transparent material layer and the second reflecting material layer.

11. The light emitting diode package structure of claim 1, wherein:

the wavelength conversion material layer has a thickness of 5 μ

m-200 μ

m and a planar upper surface.

12. The light emitting diode package structure of claim 1, wherein:

an upper surface of the wavelength conversion material layer is roughened.

13. The light emitting diode package structure of claim 1, wherein:

an upper surface of the wavelength conversion material layer has an arc structure.

14. The light emitting diode package structure of claim 1, wherein:

the wavelength conversion material layer has an optical lens.

15. The light emitting diode package structure of claim 1, wherein:

the flip chip electrodes contain Cu or Au and have a thickness of 10 μ

m-100 μ

m.

16. A light emitting diode package structure, comprising:

a first reflecting material layer comprising a reflective glue with through holes;

an inverted-trapezoidal flip chip on the first reflecting material layer, with electrodes inlaid in the through holes of the first reflecting material layer;

a second reflecting material layer comprising a reflective glue surrounding the inverted-trapezoidal flip chip, wherein an interface between the second reflecting material layer and the flip chip forms an optical cup for upward light reflection of the flip chip; and

a wavelength conversion material layer over the first reflecting material layer, the inverted-trapezoidal flip chip, and the second reflecting material layer.

17. The light emitting diode package structure of claim 16, wherein the light emitting diode package structure is manufactured by:

providing a fluorescent film;

bonding a plurality of flip chips to the fluorescent film where the flip chip electrodes are distal from the fluorescent film;

forming a transparent material layer comprising transparent glue on the fluorescent film surrounding a side surface of the flip chip except the electrodes, wherein a side surface of the transparent material layer between adjacent flip chips is in U shape or V shape;

filling the first reflecting material layer on the flip chip and the transparent material layer;

grinding or blasting the first reflecting material layer till the flip chip electrodes are exposed such that the upper surface of the first reflecting material layer is not higher than the upper surface of the flip chip electrodes; and

forming a plurality of units by cutting along central lines of adjacent flip chips to obtain a light emitting diode package structure.