LED light source device and manufacturing method for the same

• US 9,159,892 B2
• Filed: 07/01/2011
• Issued: 10/13/2015
• Est. Priority Date: 07/01/2010
• Status: Active Grant

• Current Assignee: Citizen Watch Co Limited (Citizen Electronics Company Limited)
• Original Assignee: Citizen Electronics Company Limited, Citizen Holdings Co., Ltd.
• Inventors: Fukushima, Mizue, Imazu, Kenji, Tsukada, Hiroshi, Tamura, Ryo
• Primary Examiner(s): HO, HOANG QUAN TRAN
• Application Number:
  US13/807,275
• Publication Number:
  US 20130099276A1
• Time in Patent Office: 1,565 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: H01L 2224/16225 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 2224/48237 connecting the wire to a die pad of the item
• 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 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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 2924/01322 Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/15153 the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/3025 Electromagnetic shielding
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• CPC Class Codes: H01L 33/52 Encapsulations
• 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
• CPC Class Codes: H01L 33/64 Heat extraction or cooling elements

Abstract

An object of the invention is to provide an LED light source device and a manufacturing method for the same that can maintain high reflectance over an extended period of time notwithstanding the interaction between light and heat. More specifically, the invention provides an LED light source device that includes a substrate, an electrode formed on the substrate, a white inorganic resist layer deposited over the substrate so as to cover a surface thereof everywhere except where the electrode is formed, and an LED element connected to the electrode, wherein the white inorganic resist layer contains fine white inorganic particles dispersed or mixed into an inorganic binder, and a method for manufacturing such an LED light source device.

Claims

1. An LED light source device comprising:

a substrate;

an electrode formed on said substrate;

a conductive post stacked on said electrode;

an LED element connected to said conductive post,

wherein a white inorganic resist layer contains fine white inorganic particles dispersed or mixed into an inorganic binder,

a white organic resist layer interposed between said white inorganic resist layer and said substrate,

said white inorganic resist layer is deposited over said substrate so as to cover a surface thereof everywhere except where said conductive post is formed, and

a level of the upper surface of said conductive post is substantially the same as a level of the upper surface of said white inorganic resist.

2. The LED light source device according to claim 1, wherein said conductive post has a columnar structure.

3. The LED light source device according to claim 1, wherein said LED element is flip-chip mounted on said conductive post.

4. The LED light source device according to claim 3, wherein said LED element is connected to said conductive post by gold-tin eutectic bonding.

5. The LED light source device according to claim 1, further comprising a zener diode covered with said white inorganic resist layer and connected to said LED element.

6. The LED light source device according to claim 1, wherein said substrate is a resin substrate.

7. The LED light source device according to claim 1, wherein said substrate is an inorganic substrate.

8. The LED light source device according to claim 1, wherein the surface of said white inorganic resist layer is even.

9. The LED light source device according to claim 1, wherein the surface of said white inorganic resist layer only around said conductive post is even.

10. The LED light source device according to claim 1, wherein an upper surface area of said conductive post is smaller than an upper surface area of said electrode.