LED lamp and LED lamp manufacturing method

• US 20030025450A1
• Filed: 07/29/2002
• Published: 02/06/2003
• Est. Priority Date: 08/01/2001
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Katayama, Hiroyuki, Murata, Kazuhisa, Katoh, Masaaki
• Granted Patent: US 6,939,188 B2
• Time in Patent Office: Days
• US Class Current: 313/512
• CPC Class Codes: G09F 9/33 being semiconductor devices, e.g. diodes
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• 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 2924/00012 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 2924/181 Encapsulation
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating

Abstract

An LED lamps capable of composing a display panel that is installed at any outdoor place and capable of displaying an image thereon with a high contrast under any working conditions at any place. The LED lamp comprises at least one LED chip for emitting visible light, a lead frame comprising a common part and separate parts for supplying electric power to each of electrode terminals of the LED chip and a transparent resin part disposed on the common lead frame for mounting the LED chip and converging light emitted from the LED chip, wherein the LED-chip-mounted surface is provided with an anti-reflection black-colored layer for absorbing light. The LED chip may be a four-element LED chip composed of an active layer of AlGaInP and the light-absorbing layer formed from any of black silver sulfide, silver oxide, iron oxide, chromium oxide, black silver paste and black copper paste.

Claims

1. An LED (Light-Emitting Diode) lamp comprising at least an LED chip for emitting visible light, a lead frame comprising a common part and separate parts for supplying electric power to each of electrode terminals of the LED chip and a transparent resin part disposed on the lead frame for mounting the LED chip and conversing light emitted from the LED chip, wherein the LED-chip-mounted surface with the LED chip mounted whereon is provided with a black-colored light-absorbing layer.

2. A LED lamp as defined in claim 1, wherein the LED chip is a four-element LED chip having an active layer of AlGaInP.

3. A LED lamp as defined in claim 1 or 2, wherein the LED-chip-mounted surface is in the form of a plain plate.

4. A LED lamp as defined in claim 1 or 2, wherein the LED-chip-mounted surface is in the form of a cup open in the direction of light path and having outwardly slanting wall surrounding the LED chip mounted therein.

5. A LED lamp as defined in claim 1 or 2, wherein the light-absorbing layer formed on the LED-chip-mounted surface is made of any one of black silver sulfide, black silver oxide, black iron oxide, black chromium oxide, black silver paste and black copper paste.

6. A LED lamp as defined in claim 1 or 2, wherein the light-absorbing layer formed on the LED-chip-mounted surface is made of any of main components such as nickel, chromium, zinc and black resin.

7. A method of manufacturing an LED lamp, whereby a black silver sulfide composing a light-absorbing layer as defined in claim 5 is formed by sulfurizing a silver surface with hydrogen sulfide solution or hydrogen sulfide gas after connecting electrode terminals of LED chips to a silver-plated common part by die-bonding using silver paste and separate parts by wire-bonding.

8. A method of manufacturing an LED lamp, whereby a black silver oxide composing a light-absorbing layer as defined in claim 6 is formed by oxidizing a silver surface by immersing into nitric acid solution or exposing to ultraviolet rays in oxygen gas atmosphere after connecting electrode terminals of LED chips to a silver-plated common part by die-bonding using silver paste and separate parts by wire-bonding.