SEMICONDUCTOR LIGHT EMITTING STRUCTURE

• US 20170047484A1
• Filed: 05/31/2016
• Published: 02/16/2017
• Est. Priority Date: 08/13/2015
• Status: Abandoned Application

• Current Assignee: Lextar Electronics Corporation
• Original Assignee: Lextar Electronics Corporation
• Inventors: Lai, Shih-Huan, Kuo, Shiou-Yi, Wang, Te-Chung
• Application Number:
  US15/168,285
• Publication Number:
  US 20170047484A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01L 33/145 with a current-blocking structure
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/382 the electrode extending partially in or entirely through the semiconductor body
• CPC Class Codes: H01L 33/405 Reflective materials
• CPC Class Codes: H01L 33/42 Transparent materials
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• 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 semiconductor light emitting structure includes a first type semiconductor layer, an active layer, a second type semiconductor layer, an electrode, a transparent conductive layer, a Bragg reflective layer and a metal layer. The first type semiconductor layer, the active layer and the second type semiconductor layer are stacked sequentially to form an epitaxy layer. The electrode is formed on the first type semiconductor layer. The transparent conductive layer is formed on the second type semiconductor layer. The Bragg reflective layer is formed on the transparent conductive layer. The Bragg reflective layer and electrode are disposed on opposite sides of the epitaxy layer. The metal layer is formed on the Bragg reflective layer. The Bragg reflective layer has a concave portion into which the metal layer is put. The metal layer has a current conducting portion embedded into the concave portion and electrically connected to the transparent conductive layer.

Claims

1. A semiconductor light emitting structure, comprising:

a first type semiconductor layer;

an active layer;

a second type semiconductor layer, wherein the second type semiconductor layer, the active layer and the first type semiconductor layer are stacked sequentially to form an epitaxy layer;

an electrode formed on the first type semiconductor layer;

a transparent conductive layer formed on the second type semiconductor layer;

a Bragg reflective layer formed on the transparent conductive layer, wherein the Bragg reflective layer and the electrode are formed on two opposite sides of the epitaxy layer; and

a metal layer formed on the Bragg reflective layer.

wherein, the Bragg reflective layer has a first concave portion into which the metal layer is put, such that the metal layer has a current conducting portion embedded into the first concave portion and electrically connected to the transparent conductive layer.

2. The semiconductor light emitting structure according to claim 1, further comprising a contact pad formed on the transparent conductive layer and located between the current conducting portion and the transparent conductive layer.

3. The semiconductor light emitting structure according to claim 1, wherein the transparent conductive layer has a second concave portion into which the Bragg reflective layer is embedded, such that the Bragg reflective layer has a current blocking portion embedded into the second concave portion and electrically connected to the second type semiconductor layer.

4. The semiconductor light emitting structure according to claim 3, wherein the position of the electrode is aligned with that of the current blocking portion.

5. The semiconductor light emitting structure according to claim 3, further comprising a contact pad formed on the transparent conductive layer and located between the current conducting portion and the transparent conductive layer.

6. A semiconductor light emitting structure, comprising:

a first type semiconductor layer;

an active layer;

a second type semiconductor layer, wherein the second type semiconductor layer, the active layer and the first type semiconductor layer are stacked sequentially to form an epitaxy layer;

a first Bragg reflective layer formed on the second type semiconductor layer.

a transparent conductive layer formed on the first Bragg reflective layer;

a second Bragg reflective layer formed on the transparent conductive layer, wherein the first Bragg reflective layer has a first recess into which the transparent conductive layer and the second Bragg reflective layer are put, such that the transparent conductive layer has a current diffusion portion embedded into the first recess; and

a metal layer formed on the second Bragg reflective layer, wherein the second Bragg reflective layer has a second recess into which the metal layer is put, such that the metal layer has a current conducting portion embedded into the second recess and electrically connected to the transparent conductive layer.

7. The semiconductor light emitting structure according to claim 6,

wherein the first Bragg reflective layer corresponding to the current conducting portion and forms a current blocking portion.

8. The semiconductor light emitting structure according to claim 6, wherein a reflectivity of the second Bragg reflective layer is larger than a reflectivity of the first Bragg reflective layer.

9. The semiconductor light emitting structure according to claim 7, further comprising an electrode formed on the first type semiconductor, wherein the electrode and the current blocking portion are disposed on two opposite sides of the epitaxy layer, and the position of the electrode is aligned with that of the current blocking portion.

10. The semiconductor light emitting structure according to claim 6, further comprising:

a first protection layer covering the metal layer and formed in a through hole passing through the second type semiconductor layer, the active layer and a part of the first type semiconductor layer;

a contact layer disposed on the first protection layer, wherein the contact layer is electrically connected to the first type semiconductor layer in the through hole;

a second protection layer covering the contact layer, wherein the second protection layer has a third recess and a fourth recess;

a first electrode disposed on the second protection layer and put into the third recess to be electrically connected to the metal layer; and

a second electrode disposed on the second protection layer and put into the fourth recess to be electrically connected to the contact layer.