Light emitting device using gan led chip

• US 20100019247A1
• Filed: 10/05/2007
• Published: 01/28/2010
• Est. Priority Date: 10/05/2006
• Status: Active Grant

• Current Assignee: Mitsubishi Chemical Corporation (Mitsubishi Chemical Group Corp.)
• Original Assignee: Mitsubishi Chemical Corporation (Mitsubishi Chemical Group Corp.)
• Inventors: Taniguchi, Hirokazu, Shima, Toshihiko, Hiraoka, Shin, Okagawa, Hiroaki, Joichi, Takahide
• Granted Patent: US 8,158,990 B2
• Time in Patent Office: Days
• US Class Current: 257/76
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/32014 the layer connector being smaller than the bonding area, e.g. bond pad
• 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 2224/73265 Layer and wire connectors
• 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 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/405 Reflective materials
• 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

Abstract

A light emitting device is constituted by flip-chip mounting a GaN-based LED chip 100 of the following (a):

• (a) the a GaN-based LED chip 100 comprising a light-transmissive substrate 101 and GaN-based semiconductor layer L formed on the light-transmissive substrate 101, wherein the GaN-based semiconductor layer L has a laminate structure containing n-type layer 102, light emitting layer 103 and p-type layer 104 in this order from the light-transmissive substrate 101 side, wherein a positive electrode E101 is formed on the p-type layer 104, said electrode E101 containing a light-transmissive electrode E101a of an oxide semiconductor and a positive contact electrode E101b electrically connected to the light-transmissive electrode, and the area of the positive contact electrode E101b is less than ½ of the area of the upper surface of the p-type layer 104.

Claims

1. A light emitting device wherein a GaN-based LED chip of the following (a) is flip-chip mounted:

(a) a GaN-based LED chip comprising a light-transmissive substrate and a GaN-based semiconductor layer formed on the light-transmissive substrate, the GaN-based semiconductor layer having a laminate structure comprising an n-type layer, a light emitting layer and a p-type layer in this order from the light-transmissive substrate side,

wherein a positive electrode is formed on the p-type layer, said electrode comprising

a light-transmissive electrode composed of an oxide semiconductor and

a positive contact electrode electrically connected to the light-transmissive electrode, and

the area of the positive contact electrode is less than ½

of the area of the upper surface of the p-type layer.

2. The light emitting device of claim 1, wherein the positive contact electrode has an area less than ⅓

of the area of the upper surface of the p-type layer.

3. The light emitting device of claim 2, wherein the positive contact electrode has an area less than ¼

of the area of the upper surface of the p-type layer.

4. The light emitting device of claim 3, wherein the GaN-based LED chip is encapsulated with a resin.

5. The light emitting device of claim 4, wherein the light-transmissive electrode has a surface planarized by polishing.