Light emitting diode package having multi-stepped reflecting surface structure and fabrication method thereof

• US 8,586,128 B2
• Filed: 05/18/2009
• Issued: 11/19/2013
• Est. Priority Date: 04/21/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Shin, Sang Hyun, Choi, Seog Moon, Lee, Young Ki
• Primary Examiner(s): Talbot, Brian K
• Application Number:
  US12/467,513
• Publication Number:
  US 20090227050A1
• Time in Patent Office: 1,646 Days
• Field of Search: 427/74, 427/77, 427/64
• US Class Current: 427/64
• CPC Class Codes: H01L 2224/48091 Arched
• 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 33/483 Containers
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/641 characterized by the materials

Abstract

A high luminance and high output LED package using an LED as a light source and a fabrication method thereof. The LED package includes an Al substrate with a recessed multi-stepped reflecting surface formed therein and a light source composed of LEDs mounted on the reflecting surface and electrically connected to patterned electrodes. The LED package also includes anodized insulation layers formed between the patterned electrodes and the substrate, and an encapsulant covering over the light source of the substrate. The LED package further includes an Al heat radiator formed under the LEDs to enhance heat radiation capacity. According to the present invention, the substrate is made of Al material and anodized to form insulation layers thereon, allowing superior heat radiation effect of the LED, thereby significantly increasing the lifetime and light emission efficiency of the LED package.

Claims

1. A method of fabricating an LED package, comprising:

etching a first surface of a substrate to integrally form a multi-stepped reflecting surface therein, the multi-stepped reflecting surface having a first inclined reflecting surface portion, a central reflecting surface portion, and a second inclined reflecting surface portion extending from the central reflecting surface portion;

anodizing second surfaces of the substrate to form insulation layers on an upper surface of the substrate and on a lower surface of the substrate excluding the central reflecting surface portion and the second inclined reflecting surface portion;

forming patterned electrodes on the insulation layers;

mounting a light source on the central reflecting surface portion of the substrate and electrically connecting the light source to the substrate and the patterned electrodes respectively; and

forming an encapsulant over the light source mounted on the substrate,

wherein one of the patterned electrodes formed on an upper surface of the insulation layer, which is formed on the upper surface of the substrate, extends from an upper part of the substrate to a middle step of the multi-stepped reflecting surface, without extending beyond the middle step, and is electrically connected with the light source,

wherein the etching step comprises;

forming a first photoresist layer on the first surface of the substrate and selectively etching the first surface of the substrate to form the first inclined reflecting surface portion; and

forming a second photoresist layer on an inner side of the first inclined reflecting surface portion and selectively etching an inner side surface of the substrate to form the second inclined reflecting surface portion and to form the central reflecting surface portion on which the light source is seated,

wherein the first inclined reflecting surface portion and the middle step between the first inclined reflecting surface portion and the second inclined reflecting surface portion have a ring shaped structure surrounding the central reflecting surface portion.

2. The method according to claim 1, wherein the encapsulant forming step comprises dispensing and curing a transparent material selected from the group consisting of a silicone resin, an epoxy resin, an Epoxy Molding Compound (EMC) and mixtures thereof in a recessed space of the reflecting surface of the substrate.

3. The method according to claim 1, further comprising dicing a mother substrate to produce a plurality of LED packages.

4. The method according to claim 1, wherein the substrate is anodized on the second surfaces thereof to form the insulation layers except on the multi-stepped reflecting surface.

5. The method according to claim 1, further comprising coating a highly reflective metallic material on the multi-stepped reflecting surface.