CN102856456B - Vertical type light emitting diode - Google Patents
Vertical type light emitting diode Download PDFInfo
- Publication number
- CN102856456B CN102856456B CN201210351448.9A CN201210351448A CN102856456B CN 102856456 B CN102856456 B CN 102856456B CN 201210351448 A CN201210351448 A CN 201210351448A CN 102856456 B CN102856456 B CN 102856456B
- Authority
- CN
- China
- Prior art keywords
- layer
- emitting diode
- type
- light
- light emitting
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Led Devices (AREA)
Abstract
The invention discloses a kind of vertical type light emitting diode, it has substrate, the lower surface of described substrate is formed with transparent metal ohmic contact layer, be formed with n-type electrode below described transparent metal ohmic contact layer, this n-type electrode realizes being electrically connected with described substrate by described transparent metal ohmic contact layer; The upper surface of described substrate is formed with successively GaN resilient coating, n-type GaN layer, multiple quantum well light emitting layer (MQW), p-type AlGaN layer, p-type GaN layer, transparent electrode layer, p metal electrode, the surface of described GaN resilient coating is roughened process rear formation first surface roughened layer; The upper surface of described vertical type light emitting diode, lower surface and all sides all form second surface roughened layer.
Description
Technical field
The invention belongs to technical field of semiconductors, particularly a kind of light-emitting diode of vertical-type.
Background technology
Semiconductor light-emitting-diode application is increasingly extensive, and in illumination, particularly have the trend replacing incandescent lamp and fluorescent lamp, but also face some technical problems at present, particularly light extraction efficiency is lower.
In recent years, in order to improve luminous power and the efficiency of light-emitting diode, develop the light-emitting diode of vertical stratification, relative to the light-emitting diode of positive assembling structure, the light-emitting diode plurality of advantages of vertical stratification.For the light-emitting diode of positive assembling structure, because n, p-electrode are all in the same side of substrate, therefore electric current must between the n of homonymy, p-type electrode lateral flow, so just cause current crowding, caloric value is high.And two of light emitting diode with vertical structure electrodes are in the both sides of light-emitting diode respectively, electric current almost all flows vertically through epitaxial loayer, does not have the electric current of lateral flow, therefore homogeneous current distribution, and the heat of generation is relatively less.And because two electrodes of vertical stratification are in both sides, therefore go out the stop that can not be subject to same lateral electrode in photoreduction process, its light extraction efficiency is higher.
In the practical work process of light-emitting diode, when light leaves diode inside, in any case it all cannot avoid loss occurs, causing the main cause of loss, is that the semi-conducting material owing to forming LED surface layer has high index of refraction.High optical refractive index can cause light to produce total reflection at this semiconductor material surface, thus the light that LED internal is sent cannot be launched fully.At present, improve the total reflection of light in diode inside by surface texture technology in the industry, thus raising luminous efficiency, but, because prior art usually only carries out roughening treatment to the surface that diode portion is grouped into structure, which results in its roughened surface skewness, therefore cannot effective improving luminous efficiency.
Simultaneously, light-emitting diode send only by its internal structure luminescent layer produce, the light that luminescent layer sends mainly is sent by the front of light-emitting diode, and the light sent from its side must first through the total reflection of LED internal structure, the light path of light is changed could be sent by side.Which results in existing light-emitting diode front bright dipping too much and side bright dipping is not enough, therefore also just cause the uneven of light-emitting diode bright dipping.
Fig. 1 is existing vertical type light emitting diode.In Fig. 1, be formed with transparent metal ohmic contact layer 100 below substrate 101, n-type electrode 111 realizes being electrically connected with this substrate 101 by this transparent metal ohmic contact layer 100.And above substrate 101, form GaN resilient coating 102, n-type GaN layer 103, multiple quantum well light emitting layer (MQW) 104, p-type AlGaN layer 105, p-type GaN layer 106, transparent electrode layer 107, p metal electrode 112 successively; Wherein GaN resilient coating 102 surface is roughened process, to form nano level jagged surface coarsening layer 122.
In the light emitting diode construction shown in Fig. 1, because roughened layer is only formed at the inside of light-emitting diode, on the surface of i.e. GaN resilient coating 102, therefore, although the light produced by multiple quantum well light emitting layer 104 is through the reflection of roughened layer 122, can improve the luminous efficiency of side in certain degree, but this roughened layer be in LED internal is also not enough to improve luminous efficiency further.
And, the light-emitting diode of structure shown in Figure 1, what visible multiple quantum well light emitting layer 104 sent wide is manyly appeared by the front of light-emitting diode, namely appeared by the upper surface of transparent electrode layer 107, only have a small amount of light to be appeared by the side of light-emitting diode after the total reflection of transparent electrode layer 107.Therefore, the uniformity of luminance of the light-emitting diode of structure shown in Fig. 1 need to improve.
Summary of the invention
The present invention is directed to the problem of prior art, propose a kind of vertical type light emitting diode with coarse surface and reflector, thus improve luminous efficiency and the uniformity of luminance of light-emitting diode.
The vertical type light emitting diode that the present invention proposes has substrate, the lower surface of described substrate is formed with transparent metal ohmic contact layer, be formed with n-type electrode below described transparent metal ohmic contact layer, this n-type electrode realizes being electrically connected with described substrate by described transparent metal ohmic contact layer; The upper surface of described substrate is formed with successively GaN resilient coating, n-type GaN layer, multiple quantum well light emitting layer (MQW), p-type AlGaN layer, p-type GaN layer, transparent electrode layer, p metal electrode; The surface of described GaN resilient coating is roughened process rear formation first surface roughened layer; The upper surface of described vertical type light emitting diode, lower surface and all sides all form second surface roughened layer.
Wherein, described first surface roughened layer and second surface roughened layer are all nanoscale zigzag roughened layer.
Wherein, the upper surface of described p-type GaN layer is formed with the parallel reflector of two rows.
Wherein, described reflector is the anti-layer of Al/Ag alloying metal, AlAs/AlxGa1-xAs distributed Bragg reflecting layer (DBR) or AlInP/ (AlxGa1-x) yIn1-yP distributed Bragg reflecting layer (DBR).
Accompanying drawing explanation
Accompanying drawing 1 is the light emitting diode construction schematic diagram only having part coarse surface in prior art.
The light emitting diode construction schematic diagram with coarse surface and reflector that accompanying drawing 2 proposes for the present invention.
The planar structure schematic diagram that accompanying drawing 3 is light-emitting diode shown in Fig. 2.
Embodiment
Fig. 2 is the vertical type light emitting diode that the present invention proposes, and it has the surface of comprehensive alligatoring, and has reflector, therefore, it is possible to significantly improve luminous efficiency and uniformity of luminance.
See Fig. 2, the structure of light-emitting diode 2 is as described below: be formed with transparent resistive metal layer 200 in the below of substrate 201, and n-type electrode 211 realizes being electrically connected with this substrate 201 by this transparent metal ohmic contact layer 200.Surface on the substrate 201, it forms GaN resilient coating 202, n-type GaN layer 203, multiple quantum well light emitting layer (MQW) 204, p-type AlGaN layer 205, p-type GaN layer 206, transparent electrode layer 207, p metal electrode 212 successively.
In order to the luminous efficiency of light-emitting diode 2 significantly can be improved, in the vertical type light emitting diode structure that the present invention proposes, except carrying out roughening treatment on GaN resilient coating 202 surface, to be formed beyond nano level jagged surface coarsening layer 222, also by the upper surface of light-emitting diode 2, namely the upper surface of transparent electrode layer 207 carries out roughening treatment, meanwhile, also further roughening treatment is carried out equally in all sides of light-emitting diode 2, thus form surface coarsening layer 221 as shown in Figure 2.This roughening treatment can carry out wet etching by being immersed in alkaline solution by light-emitting diode 2, utilizes alkaline solution to carry out corrosion to its surface and has come.Also plasma chambers can being utilized to carry out dry etching to light-emitting diode come, wet etching can also being carried out and then utilize plasma chambers to carry out dry etching having combined by being first immersed in alkaline solution.Combine for wet etching and dry etching and form the technique of surface coarsening layer, the present invention does not limit must dry etching after first wet etching, adopts first dry etching to be equally also fine at wet etching.
After roughening treatment is carried out to the whole outer surface of light-emitting diode 2, the light that multiple quantum well light emitting layer 204 sends is behind each surface arriving light-emitting diode 2, light outside transmission critical angle is due to the repeatedly refraction through surface coarsening layer, finally can enter critical angle interior by each surface transmission out, thus make light-emitting diode 2 send more light, therefore also just improve luminous efficiency.
In order to solve the problem of lumination of light emitting diode lack of uniformity in prior art, the light-emitting diode that the present invention proposes also is provided with reflector further.See Fig. 2, two row reflector 231 and 232 are provided with in p-type GaN layer 206, this reflector 231 and 232 can be Al/Ag alloying metal reflector, also can be AlAs/AlxGa1-xAs or AlInP/ (AlxGa1-x) yIn1-yP distributed Bragg reflecting layer (DBR).This reflector 231 and 232 can be arranged on the upper surface (as shown in Figure 2) of p-type GaN layer 206, also can be arranged on the upper surface (not shown in Fig. 2) of p-type AlGaN layer 205, or the lower surface being arranged on p-type GaN layer 206 or p-type AlGaN layer 205 also can.
See Fig. 2, by arranging reflector 231 and 232, a part for the light sent by multiple quantum well light emitting layer 204 is directly appeared by the front of light-emitting diode 2, and another part is then appeared by the side of light-emitting diode 2 after the reflection in reflector 231 and 232.Owing to there being the existence in reflector 231 and 232, the light that so can arrive light-emitting diode 2 front is just restricted to the part in Fig. 2 between reflector 231 and 232, and the light reflected by reflector 231 and 232 can only appear from the side of light-emitting diode 2, therefore, this design just can improve the uniformity of luminance of light-emitting diode front and side.
Fig. 3 is the floor map of Fig. 2, is namely overlooked by the top of Fig. 2 and the schematic diagram obtained.See Fig. 3, reflector 231 and 232 is two parallel array structures, a part for the light that the multiple quantum well light emitting layer 204 of light-emitting diode 2 sends is appeared by the region 300 in Fig. 3, and another part light appears from the side of light-emitting diode due to the reflection in reflector 232 and 231.
So far, foregoing description specifically understands light emitting diode construction of the present invention, now for existing light-emitting diode, while the structure that the present invention proposes can increase substantially luminous efficiency, the uniformity of luminance of light-emitting diode can also be improved further.The embodiment of description is above only the preferred embodiments of the present invention, and it is not intended to limit the present invention.Those skilled in the art, under the prerequisite not departing from spirit of the present invention, can make any amendment, and protection scope of the present invention are limited to the appended claims to the present invention.
Claims (2)
1. a vertical type light emitting diode, it is made up of 8 Rotating fields, described light-emitting diode has transparent metal ohmic contact layer (200), n-type electrode (211) is directly formed at the lower surface of transparent metal ohmic contact layer (200), directly be formed with substrate (201) at the upper surface of transparent metal ohmic contact layer (200), this n-type electrode (211) realizes being electrically connected with described substrate (201) by described transparent metal ohmic contact layer (200); The upper surface of described substrate (201) is directly formed with GaN resilient coating (202), GaN resilient coating (202) is directly formed n-type GaN layer (203), n-type GaN layer (203) is upper directly forms multiple quantum well light emitting layer (204); Multiple quantum well light emitting layer (204) is upper directly forms p-type AlGaN layer (205); P-type AlGaN layer (205) is directly formed p-type GaN layer (206), p-type GaN layer (206) is directly formed transparent electrode layer (207), transparent electrode layer (207) is upper directly forms p metal electrode (212), it is characterized in that:
The surface of described GaN resilient coating (202) is roughened process rear formation first surface roughened layer (222);
The upper surface of described vertical type light emitting diode, lower surface and all sides all form second surface roughened layer (221);
Described first surface roughened layer (222) and second surface roughened layer (221) are all nanoscale zigzag roughened layer;
Described light-emitting diode is also provided with reflector (231 further, 231), this reflector (231,231) is only arranged in p-type GaN layer, and the upper surface of reflector (232,231) and the upper surface flush of p-type GaN layer (206);
Wherein, the upper surface of described transparent electrode layer (207) blanket p-type GaN layer (206) and reflector (231,232).
2. vertical type light emitting diode as claimed in claim 1, is characterized in that:
Described reflector is the anti-layer of Al/Ag alloying metal, AlAs/AlxGa1-xAs distributed Bragg reflecting layer (DBR) or AlInP/ (AlxGa1-x) yIn1-yP distributed Bragg reflecting layer (DBR).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210351448.9A CN102856456B (en) | 2012-09-20 | 2012-09-20 | Vertical type light emitting diode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210351448.9A CN102856456B (en) | 2012-09-20 | 2012-09-20 | Vertical type light emitting diode |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102856456A CN102856456A (en) | 2013-01-02 |
| CN102856456B true CN102856456B (en) | 2015-11-25 |
Family
ID=47402847
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210351448.9A Expired - Fee Related CN102856456B (en) | 2012-09-20 | 2012-09-20 | Vertical type light emitting diode |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102856456B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105470361A (en) * | 2015-12-31 | 2016-04-06 | 天津三安光电有限公司 | Roughened invisible light all-angle light-emitting diode and fabrication method thereof |
| GB2595685B (en) * | 2020-06-03 | 2024-08-07 | Plessey Semiconductors Ltd | Spacer LED architecture for high efficiency micro LED displays |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101075652A (en) * | 2006-09-05 | 2007-11-21 | 武汉迪源光电科技有限公司 | Production of coarsening electrode for high-brightness packed LED chip and vertical LED chip |
| CN101789477A (en) * | 2010-02-24 | 2010-07-28 | 中国科学院半导体研究所 | Method for preparing all-side-wall saw-tooth coarsened light-emitting diode chip |
| CN102064251A (en) * | 2010-11-23 | 2011-05-18 | 吉林大学 | High-power SiC substrate vertical structure light-emitting diode and preparation method thereof |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000065667A1 (en) * | 1999-04-28 | 2000-11-02 | Nova Crystals, Inc. | Led having embedded light reflectors to enhance led output efficiency |
| SG140473A1 (en) * | 2006-08-16 | 2008-03-28 | Tinggi Tech Private Ltd | Improvements in external light efficiency of light emitting diodes |
-
2012
- 2012-09-20 CN CN201210351448.9A patent/CN102856456B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101075652A (en) * | 2006-09-05 | 2007-11-21 | 武汉迪源光电科技有限公司 | Production of coarsening electrode for high-brightness packed LED chip and vertical LED chip |
| CN101789477A (en) * | 2010-02-24 | 2010-07-28 | 中国科学院半导体研究所 | Method for preparing all-side-wall saw-tooth coarsened light-emitting diode chip |
| CN102064251A (en) * | 2010-11-23 | 2011-05-18 | 吉林大学 | High-power SiC substrate vertical structure light-emitting diode and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102856456A (en) | 2013-01-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102074629B (en) | Light emitting diode with sandwich-type current blocking structure | |
| KR101761385B1 (en) | Light emitting device | |
| JP2011129890A (en) | Light-emitting device showing uniform spread of current | |
| CN105355742A (en) | Light emitting diode chip and manufacturing method thereof | |
| CN102983233B (en) | The manufacture method of gallium nitride based light emitting diode | |
| CN102856456B (en) | Vertical type light emitting diode | |
| CN102983232B (en) | The manufacture method of vertical type light emitting diode | |
| CN102881796B (en) | Light-emitting device with annular reflective layer | |
| TWI569471B (en) | Semiconductor light emitting structure and manufacturing method thereof | |
| CN104465919B (en) | Light-emitting diode and manufacturing method thereof | |
| CN102983231B (en) | There is the manufacture method of the light-emitting diode in cubic circulus reflector | |
| CN102790156B (en) | Semiconductor light emitting structure | |
| CN106159054A (en) | Light emitting diode | |
| CN102832309B (en) | There is cubic circulus reflector gallium nitride based light emitting diode | |
| CN102856457B (en) | Gallium nitride based light emitting diode | |
| CN201893369U (en) | LED (Light-Emitting Diode) | |
| CN103594593B (en) | There is the manufacture method of the inverted light-emitting diode (LED) of alligatoring transparency electrode | |
| CN205828417U (en) | A kind of filament light-emitting diode chip for backlight unit | |
| CN103594591B (en) | There is the manufacture method of the inverted light-emitting diode (LED) of transparency electrode | |
| CN102983238B (en) | Manufacturing method of luminescent device with annular reflecting layer | |
| EP2445017A2 (en) | Vertical light-emitting semiconductor device | |
| CN103594594B (en) | There is the inverted light-emitting diode (LED) of roughening transparency electrode | |
| CN202917531U (en) | High-efficiency high-voltage LED chip | |
| CN103606617B (en) | There is the inverted light-emitting diode (LED) of transparency electrode | |
| CN103594569B (en) | There is the manufacture method of the inverted light-emitting diode (LED) of alligatoring transparency electrode |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20151125 Termination date: 20160920 |