Method for manufacturing phosphor film and method for making LED package having the phosphor film

• US 8,658,445 B2
• Filed: 08/30/2012
• Issued: 02/25/2014
• Est. Priority Date: 02/16/2012
• Status: Active Grant

• Current Assignee: Advanced Optoelectronic Technology, Inc.
• Original Assignee: Advanced Optoelectronic Technology, Inc.
• Inventors: Tseng, Wen-Liang, Chen, Pin-Chuan, Chen, Lung-hsin
• Primary Examiner(s): BOOTH, RICHARD A
• Application Number:
  US13/600,128
• Publication Number:
  US 20130217160A1
• Time in Patent Office: 544 Days
• Field of Search: 438 26- 28, 438/112, 438/124, 438126-127
• US Class Current: 438/26
• CPC Class Codes: C09K 11/02 Use of particular materials as binders, particle coatings or suspension media therefor
• CPC Class Codes: C09K 11/08 containing inorganic luminescent materials
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/92247 the second connecting process involving a wire connector
• 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 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 33/50 Wavelength conversion elements

Abstract

A method for manufacturing a phosphor film for use in the an LED package, includes following steps: providing a mold comprising a first and a second molding part, the first molding part and the second molding part cooperatively forming a molding chamber, the first molding part defining an opening communicating with the molding chamber; filling a mixture of phosphor particles and a transparent glue into the first opening; moving a piston in the first opening along a direction from the first molding part to the second molding part, thereby pressing the mixture into the molding chamber; solidifying the mixture to form a phosphor film; and removing the phosphor film from the mold. The phosphor film is used to be attached to a top face of an LED chip opposite a substrate on which the LED chip is mounted.

Claims

1. A method for manufacturing a phosphor film for use in an LED (light emitting diode) package to change color of light from the LED package, comprising following steps:

providing a mold, the mold comprising a first molding part and a second molding part, the first molding part and the second molding part cooperatively forming a molding chamber, the first molding part defining an opening communicating with the molding chamber;

filling a mixture of phosphor particles and a transparent glue into the first opening;

providing a piston, the piston moving in the first opening along a direction from the first molding part to the second molding part, thereby pressing the mixture of the phosphor particles and the transparent glue into the molding chamber;

solidifying the mixture of the phosphor particles and the transparent glue to form a phosphor film; and

removing the phosphor film from the mold.

2. The method of claim 1, wherein the mold further comprises a plurality of second holes, the second holes are formed at a periphery of the first molding part and communicated with the molding chamber, and wherein when the mixture of the phosphor particles and the transparent glue is filled into the molding chamber, air in the molding chamber exhausts into outer environment through the second holes.

3. The method of claim 1, wherein before removing the phosphor film from the mold, the phosphor film is patterned to form a plurality of first through holes and second through holes, then the phosphor film is cut into a plurality of phosphor film units, each phosphor film unit comprises a first through hole and a second through hole.

4. The method of claim 3, wherein the phosphor film is patterned by cutting, pressing or etching.

5. The method of claim 1, wherein the phosphor particles are made of a material selected from a group consisting of sulfides, silicates, nitrides, nitrogen oxides, hydroxid, garnets and mixtures thereof.

6. The method of claim 1, wherein the transparent glue is made of a material selected from a group consisting of silicone and epoxy resin.

7. A method for making an LED package, comprising following steps:

providing a substrate, the substrate comprising a first electrode and a second electrode on an upper surface thereof;

forming an LED chip on the substrate, the LED chip having a first electrode pad and a second electrode pad; and

attaching a phosphor film to a surface of the LED chip opposite to the substrate, the first electrode pad being electrically connected with the first electrode, and the second electrode pad being electrically connected with the second electrode, the phosphor film being manufactured in following steps;

providing a mold, the mold comprising a first molding part and a second molding part, the first molding part and the second molding part cooperatively forming a molding chamber, the first molding part defining an opening communicating with the molding chamber;

filling a mixture of phosphor particles and a transparent glue into the first opening;

providing a piston, the piston moving in the first opening along a direction from the first molding part to the second molding part, thereby pressing the mixture of the phosphor particles and the transparent glue into the molding chamber;

solidifying the mixture of the phosphor particles and the transparent glue to form a phosphor film; and

removing the phosphor film from the mold.

8. The method of claim 7, wherein a reflector cup is formed on the surface of the substrate having the LED chip, the reflector cup surrounds the LED chip, the reflector cup and the substrate cooperatively form a reflector chamber, an opening of the reflector chamber gradually increases in a direction away from the LED chip.

9. The method of claim 7, wherein a transparent encapsulation is formed inside the reflector chamber to cover the LED chip and the phosphor film.

10. The method of claim 7, wherein the mold further comprises a plurality of second holes, the second holes are formed at a periphery of the first molding part and communicated with the molding chamber, when the mixture of the phosphor particles and the transparent glue is filled into the molding chamber, air in the molding chamber exhausts into outer environment through the second holes.

11. The method of claim 7, wherein before removing the phosphor film from the mold, the phosphor film is patterned to form a plurality of first through holes and second through holes, then the phosphor film is cut into a plurality of phosphor film units, each phosphor film unit comprises a first through hole and a second through hole.

12. The method of claim 11, wherein the phosphor film is patterned by cutting, pressing or etching.

13. The method of claim 11, wherein the step of attaching a phosphor film to a surface of the LED chip opposite to the substrate is to attach one of the phosphor film units to the surface of the LED chip, with the first electrode pad passing through the first through hole, and the second electrode pad passing through the second through hole of the one of the phosphor film units.

14. The method of claim 13, wherein the first electrode pad and the second electrode pad are electrically connected with the first electrode and the second electrode by wires.

15. The method of claim 7, wherein the phosphor particles are made of a material selected from a group consisting of sulfides, silicates, nitrides, nitrogen oxides, hydroxid, garnets and mixtures thereof.

16. The method of claim 7, wherein the transparent glue is made of a material selected from a group consisting of silicone and epoxy resin.