Method of making a light emitting device and light emitting device made thereof

• US 20140159099A1
• Filed: 12/06/2013
• Published: 06/12/2014
• Est. Priority Date: 12/07/2012
• Status: Active Grant

• Current Assignee: Epistar Corporation (Ennostar, Inc.)
• Original Assignee: Epistar Corporation (Ennostar, Inc.)
• Inventors: Wu, Jar-Yu, Su, Ching-Jang, Tseng, Chun-Lung, Shen, Ching-Hsing
• Granted Patent: US 9,425,362 B2
• Time in Patent Office: Days
• US Class Current: 257/99
• CPC Class Codes: H01L 2933/0025 relating to coatings
• CPC Class Codes: H01L 33/002 having heterojunctions or graded gap
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/42 Transparent materials
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating

Abstract

A method of manufacturing a light-emitting device comprises: providing a substrate, forming a light-emitting structure on the substrate, the light-emitting structure having an active layer; forming a protective layer on the light-emitting structure, the protective layer having a first thickness; etching the protective layer such that the protective layer has a second thickness less than the first thickness; and patterning the protective layer.

Claims

1. A method of making a light emitting device, comprising steps of:

providing a substrate;

forming a light-emitting structure having an active layer on the substrate;

forming a protective layer having a first thickness on the light-emitting structure;

etching the protective layer such that the protective layer has a second thickness smaller than the first thickness; and

patterning the protective layer.

2. The method of claim 1, wherein a difference between the first thickness and the second thickness is larger than 3000 Å

.

3. The method of claim 1, further comprising forming a trench in the substrate by a laser before etching the protective layer.

4. The method of claim 1, wherein the step of etching the protective layer comprises etching the protective layer by an acidic solution.

5. The method of claim 1, wherein the second thickness is between 3000-9700 Å

.

6. The method of claim 1, wherein the step of forming the light-emitting structure comprising sequentially forming a first semiconductor layer, an active layer, and a second semiconductor layer on the substrate;

and

etching the light-emitting structure to expose a part of the first semiconductor layer before forming the protective layer.

7. The method of claim 1, further comprising forming a transparent conductive layer on the protective layer and the light-emitting structure;

and forming an electrode on the transparent conductive layer at the position corresponding to the protective layer after patterning the protective layer.

8. A light-emitting device, comprising:

a substrate;

a light-emitting structure on the substrate comprising a first region and a second region; and

a barrier layer on the first region having a bottom surface and a sidewall;

wherein an angle between the sidewall and the bottom surface is between 10°

-70°

.

9. The device of claim 8, further comprising a transparent conductive layer formed between the sidewall of the barrier layer and the second region of the light-emitting structure, wherein a difference between a thickness of the transparent conductive layer at the sidewall on the barrier layer and a thickness of the transparent conductive layer on the second region of the light-emitting structure and the thickness of the transparent conductive layer at the sidewall on the barrier layer form a ratio not larger than 10%.

10. The device of claim 8, wherein a thickness of the barrier layer is larger than 3000 Å

and less than 9700 Å

.

11. The device of claim 8, further comprising

a transparent conductive layer formed on the barrier layer;

and

a first electrode formed on the transparent conductive layer at a position corresponding to the barrier layer, wherein the first electrode has a shape substantially the same with the barrier layer.

12. The device of claim 11, wherein the first electrode comprises a first electrode pad and an extended electrode;

the light-emitting device further comprises a second electrode which comprises a second electrode pad; and

wherein the extended electrode extends from the first electrode pad to the second electrode pad.

13. The device of claim 8, further comprising

a transparent conductive layer formed on the barrier layer;

and

an electrode formed on the transparent conductive layer wherein the electrode comprises an electrode pad and an extended electrode, the light-emitting structure comprises four sides, and the barrier layer comprises an electrode region on a position corresponding to the electrode and an extension region extending to the four sides from the electrode region.

14. The device of claim 8, wherein the barrier layer comprises an insulation material having a resistance larger than 10¹⁴ Ω

-cm.

15. The device of claim 8, wherein the substrate comprises an inclined sidewall.

16. The device of claim 15, wherein the inclined sidewall comprises a rough surface.