Light emitting diode and fabrication method thereof

• US 7,339,197 B2
• Filed: 01/26/2005
• Issued: 03/04/2008
• Est. Priority Date: 09/14/2004
• Status: Active Grant

• Current Assignee: Industrial Technology Research Institute
• Original Assignee: Industrial Technology Research Institute
• Inventors: Lin, Chao-Ying, Chiang, Pel-Fang, Huang, Sheng-Bang, Yin, Sun-Bin
• Primary Examiner(s): Whitehead, Jr.; Carl
• Assistant Examiner(s): Dolan; Jennifer M.
• Application Number:
  US11/042,116
• Publication Number:
  US 20060054904A1
• Time in Patent Office: 1,133 Days
• Field of Search: 257/95, 257/E33.067, 257/E33.071, 257/E33.074, 438/27, 438/28
• US Class Current: 257/95
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/1815 Shape
• 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 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/54 having a particular shape

Abstract

A light emitting diode. The light emitting diode comprises a lead frame, a plurality of light emitting chips in the lead frame, and a molding unit in an optical path of the light emitting chips, wherein the molding unit comprises a periodic microstructure.

Claims

1. A light emitting diode, comprising:

a lead frame;

a plurality of light emitting chips in the lead frame; and

a molding unit in an optical path of the light emitting chips, wherein the molding unit comprises a periodic microstructure, and the periodic microstructure comprises conical protrusions, asymmetric pyramidal protrusions or round top pyramidal protrusions.

2. The light emitting diode as claimed in claim 1 is a monochrome light emitting diode, a white light emitting diode or a full color light emitting diode.

3. The light emitting diode as claimed in claim 1, wherein the molding unit is transparent.

4. The light emitting diode as claimed in claim 1, wherein the asymmetric pyramidal protrusions comprise a base which is asymmetric triangular pyramidal, asymmetric rectangular pyramidal, asymmetric pentangular pyramidal or asymmetric hexangular pyramidal.

5. The light emitting diode as claimed in claim 1, wherein the conical protrusions comprises flat top conical protrusions.

6. The light emitting diode as claimed in claim 1, wherein the asymmetric pyramidal protrusions comprise flat top asymmetric pyramidal protrusions.

7. The light emitting diode as claimed in claim 6, wherein the flat top asymmetric pyramidal protrusion comprise a base which is asymmetric triangular pyramidal, asymmetric rectangular pyramidal asymmetric pentangular pyramidal or asymmetric hexangular pyramidal.

8. The light emitting diode as claimed in claim 1, wherein the conical protrusions comprises round top conical protrusions.

9. The light emitting diode as claimed in claim 1, wherein the round top pyramidal protrusions comprise round top symmetric pyramidal protrusions or round top asymmetric pyramidal protrusions.

10. The light emitting diode as claimed in claim 9, wherein the round top symmetric pyramidal protrusions comprise a base which is symmetric triangular pyramidal, square pyramidal, symmetric pentangular pyramidal or symmetric hexangular pyramidal;

the round top asymmetric pyramidal protrusions comprise base which is asymmetric triangular pyramidal, asymmetric rectangular pyramidal, asymmetric pentangular pyramidal or asymmetric hexangular pyramidal.

11. The light emitting diode as claimed in claim 1, wherein the microstructure has a size of about 20 um˜

1 mm.

12. A light emitting diode fabrication method, comprising:

providing a lead frame;

providing a plurality of light emitting chips in the lead frame;

patterning a surface of a molding unit to form a periodic microstructure; and

setting the molding unit in an optical path of the light emitting chips,

wherein the periodic microstructure comprises conical protrusions, asymmetric pyramidal protrusions or round top pyramidal protrusions.

13. The light emitting diode fabrication method as claimed in claim 12, wherein the light emitting diode is a monochrome light emitting diode, a white light emitting diode or a full color light emitting diode.

14. The light emitting diode fabrication method as claimed in claim 12, wherein the molding unit is transparent.

15. The light emitting diode fabrication method as claimed in claim 12, wherein the patterning step comprises a molding step.

16. The light emitting diode fabrication method as claimed in claim 15, wherein the molding step employs a mold having a microstructure thereon.

17. The light emitting diode fabrication method as claimed in claim 12, wherein the asymmetric pyramidal protrusions comprise a base which is asymmetric triangular pyramidal, asymmetric rectangular pyramidal, asymmetric pentangular pyramidal or asymmetric hexangular pyramidal.

18. The light emitting diode fabrication method as claimed in claim 12, wherein the conical protrusion comprises flat top conical protrusions.

19. The light emitting diode fabrication method as claimed in claim 18, wherein the asymmetric pyramidal protrusions comprise flat top asymmetric pyramidal protrusions.

20. The light emitting diode fabrication method as claimed in claim 19, wherein the flat top asymmetric pyramidal protrusions comprise a base which is asymmetric triangular pyramidal, asymmetric rectangular pyramidal, asymmetric pentangular pyramidal or asymmetric hexangular pyramidal.

21. The light emitting diode fabrication method as claimed in claim 12, wherein the conical protrusions comprises round top conical protrusions.

22. The light emitting diode fabrication method as claimed in claim 12, wherein the round top pyramidal protrusions comprise round top asymmetric pyramidal protrusions or round top asymmetric pyramidal protrusions.

23. The light emitting diode fabrication method as claimed in claim 22, wherein the round top symmetric pyramidal protrusion comprise a base which is symmetric triangular pyramidal, square pyramidal, symmetric pentangular pyramidal or symmetric hexangular pyramidal;

the round top asymmetric pyramidal protrusions comprise a base which is asymmetric triangular pyramidal, asymmetric rectangular pyramidal, asymmetric pentangular pyramidal or asymmetric hexangular pyramidal.

24. The light emitting diode fabrication method as claimed in claim 12, wherein the microstructure size is smaller than the light emitting chips size.

25. The light emitting diode fabrication method as claimed in claim 12, wherein the microstructure has a size of about 20 um˜

1 mm.