CN109841713A - The face the P ohmic contact layer of reversed polarity quaternary LED and the preparation method of current extending - Google Patents
The face the P ohmic contact layer of reversed polarity quaternary LED and the preparation method of current extending Download PDFInfo
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- CN109841713A CN109841713A CN201711189562.5A CN201711189562A CN109841713A CN 109841713 A CN109841713 A CN 109841713A CN 201711189562 A CN201711189562 A CN 201711189562A CN 109841713 A CN109841713 A CN 109841713A
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- reversed polarity
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- ohmic contact
- contact layer
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- 238000002360 preparation method Methods 0.000 title claims abstract description 18
- 229920002120 photoresistant polymer Polymers 0.000 claims abstract description 16
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 13
- 238000000137 annealing Methods 0.000 claims abstract description 12
- 229910052681 coesite Inorganic materials 0.000 claims abstract description 9
- 229910052906 cristobalite Inorganic materials 0.000 claims abstract description 9
- 239000000377 silicon dioxide Substances 0.000 claims abstract description 9
- 229910052682 stishovite Inorganic materials 0.000 claims abstract description 9
- 229910052905 tridymite Inorganic materials 0.000 claims abstract description 9
- 239000000758 substrate Substances 0.000 claims description 11
- 229910001218 Gallium arsenide Inorganic materials 0.000 claims description 7
- 238000000034 method Methods 0.000 claims description 7
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 claims description 6
- 238000005260 corrosion Methods 0.000 claims description 6
- 239000007788 liquid Substances 0.000 claims description 6
- 238000005530 etching Methods 0.000 claims description 4
- 238000001259 photo etching Methods 0.000 claims description 4
- 235000012239 silicon dioxide Nutrition 0.000 claims description 4
- DDFHBQSCUXNBSA-UHFFFAOYSA-N 5-(5-carboxythiophen-2-yl)thiophene-2-carboxylic acid Chemical compound S1C(C(=O)O)=CC=C1C1=CC=C(C(O)=O)S1 DDFHBQSCUXNBSA-UHFFFAOYSA-N 0.000 claims description 3
- 238000005566 electron beam evaporation Methods 0.000 claims description 3
- 238000000623 plasma-assisted chemical vapour deposition Methods 0.000 claims description 3
- 238000007747 plating Methods 0.000 claims description 3
- 238000007740 vapor deposition Methods 0.000 claims description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 3
- 238000005516 engineering process Methods 0.000 claims description 2
- 230000000694 effects Effects 0.000 abstract description 3
- 230000000243 photosynthetic effect Effects 0.000 abstract description 3
- 238000011031 large-scale manufacturing process Methods 0.000 abstract description 2
- 239000010408 film Substances 0.000 description 41
- 239000010931 gold Substances 0.000 description 5
- 239000004065 semiconductor Substances 0.000 description 4
- 230000008033 biological extinction Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000005611 electricity Effects 0.000 description 3
- 238000005286 illumination Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 2
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- 230000007797 corrosion Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000010409 thin film Substances 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
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- 230000007613 environmental effect Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000005431 greenhouse gas Substances 0.000 description 1
- -1 not mercurous Substances 0.000 description 1
- 238000007788 roughening Methods 0.000 description 1
- 229910052594 sapphire Inorganic materials 0.000 description 1
- 239000010980 sapphire Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Abstract
The face the P ohmic contact layer of reversed polarity quaternary LED a kind of and the preparation method of current extending include the following steps: a) to grow one layer on p-type GaP layerFilm；B) negative photoresist is applied, negative photo glue-line is formed；C) corrode in the current expansion figure on p-type GaP layers of upper surfaceFilm；D) ito film except the current expansion figure on GaP layers of upper surface of p-type is removed；E) ito film in the current expansion figure on GaP layers of upper surface of p-type is subjected to high annealing.The reversed polarity AlGaInP quaternary LED chip of more high photosynthetic efficiency is obtained, the quality of chip is improved.Pass through conventional SiO2Film growth and negative photoresist stripping means obtain the P surface current extension layer of ito film, make ito film by high annealing and the face P GaP forms good Ohmic contact, easy to operate and can obtain more stable light-out effect, are suitble to large-scale production.
Description
Technical field
The present invention relates to photoelectron technical fields, and in particular to a kind of face the P ohmic contact layer and electricity of reversed polarity quaternary LED
Flow the preparation method of extension layer.
Background technique
Illumination new light sources of the LED as 21 century, under same brightness, semiconductor lamp power consumption is only the l/ of ordinary incandescent lamp
10, and the service life can extend 100 times.LED component is cold light source, and light efficiency is high, and operating voltage is low, and power consumption is small, small in size, can
Planar package is easy to develop light and thin type product, and the firm in structure and service life is very long, the harmful substances such as not mercurous, lead of light source itself, nothing
Infrared and ultraviolet pollution will not be generated in production and use to extraneous pollution.Therefore, semiconductor lamp have energy-saving and environmental protection,
The features such as service life is long, as transistor substitutes electron tube, semiconductor lamp substitutes traditional incandescent lamp and fluorescent lamp, also will be
Trend of the times.No matter from the angle saved electric energy, reduce greenhouse gas emission, or from the angle to reduce environmental pollution, LED makees
All there is the very high potential of substitution conventional illumination sources for novel illumination light source.
AlGaInP material system is initially the laser diode for being used to manufacture visible light, first by Japanese researchers
It is proposed in middle 1980s.LED the and LD device in that period, it is usually used matched with GaAs substrate
For Ga0.5In0.5P as active light emitting area, emission wavelength is 650 nm, is obtained extensively in quaternary laser pen and DVD, player
Using.Later, researcher's discovery introduced Al component in GaInP can further shorten emission wavelength, but if Al contains
Measure it is excessively high the luminous efficiency that will lead to device is sharply declined because when the Al content in GaInP is more than 0.53, AlGaInP
It will become indirect band-gap semiconductor, so AlGaInP material generally only is used to prepare the LED device of 570 nm or more of emission wavelength
Part.1997, the AlGaInP base LED birth of first multiple quantum wells (MQW) compound Bragg mirror (DBR) structure in the world
Raw, the LED component based on the design of such structure still occupies the very big share of LED low-end market so far.
Reversed polarity AlGaInP quaternary LED chip is widely used in high-power red-light LED field of display screen, antipole at this stage
Property i.e. carry out substrate displacement, the biggish GaAs substrate of extinction is replaced into monocrystalline conduction Si substrate or Sapphire Substrate etc., replace
After by the removal of GaAs substrate etching, erode corrosion barrier layer again and expose heavily doped layer, it is subsequent Au to be deposited on heavily doped layer
Film forms Ohmic contact, and subsequent photoetching prepares Ohmic contact layer pattern again, prepares the face P ohmic contact layer at this stage and be all made of AuBe
As the ohmic contact layer of GaP, and AuBe extinction makes the face P ohmic contact layer will affect luminous efficiency, how to reduce the face P ohm
The extinction of contact can preferably obtain Ohmic contact and current expansion again becomes problem main at this stage.
Chinese patent document CN205723599U discloses the reversed polarity AlGaInP base LED of surface covering ITO a kind of,
Surface covers the reversed polarity AlGaInP base LED of ITO, and metal is mainly disposed in the permanent substrate for have back electrode
Bonded layer, ODR reflecting mirror, epitaxial layer, ITO extension current extending and main electrode；The ODR reflecting mirror is by gold interconnected
Belong to reflecting layer and media coating is constituted, media coating is connected with epitaxial layer；Metallic reflector is connected with metal bonding layer；
Ohmic contact point is provided between ITO current extending and epitaxial layer；ITO current expansion layer surface is in roughening shape.The invention is suitable
For the current expansion of reversed polarity AlGaInP base LED N-type layer, the Ohmic contact and current expansion in the face P it are not related to.
Summary of the invention
That to overcome the above deficiencies, the invention provides a kind of preparation flows is easy, is largely lifted out
The preparation method of the face the P ohmic contact layer and current extending of light efficiency and more stable reversed polarity quaternary LED.
The present invention overcomes the technical solution used by its technical problem to be:
The face the P ohmic contact layer of reversed polarity quaternary LED a kind of and the preparation method of current extending, include the following steps:
A) the reversed polarity AlGaInP quaternary LED epitaxial wafer of reversed polarity quaternary epitaxial layer is grown on being completed in GaAs substrate
P-type GaP layer on grow one layerFilm；
B) in reversed polarity AlGaInP quaternary LED epitaxial waferNegative photoresist is applied on film, forms negative photo glue-line；
C) it is etched on negative photo glue-line by photoetching and forms current expansion figure, corrode the electric current on p-type GaP layers of upper surface
It extends in figureFilm；
D) one layer of ito film is deposited by way of electron beam evaporation plating in reversed polarity AlGaInP quaternary LED epitaxial wafer, by negative
Property photoresist stripping process by except the current expansion figure on GaP layers of upper surface of p-type ito film remove；
E) ito film in the current expansion figure on GaP layers of upper surface of p-type is subjected to high annealing, is made on p-type GaP layer
The face P ohmic contact layer and current extending.
Preferably, it is grown in step a) by the method for PECVD growthFilm.
Preferably, in step a)Film with a thickness of 0.3-0.4。
Preferably, in step b) negative photo glue-line with a thickness of 1.5-3。
Preferably, in the current expansion figure in step c) on p-type GaP layers of upper surface of corrosionThe step of film are as follows:
C-1 the hydrofluoric acid and pure water that the ammonium fluoride solution for being) 96% using concentration, content are 40% are 3 according to mass volume ratio:
The proportional arrangement of 6:18 or 3:9:18Corrosive liquid；
C-2) reversed polarity AlGaInP quaternary LED epitaxial wafer is placed inIt is carried out in corrosive liquidCorrosion, by negative photoresist
The SiO2 film that layer exposes is corroded.
Preferably, in step c)The etching time of film is 1-2 minutes.
Preferably, the current expansion figure in step c) is cylindrical or linear structure.
Preferably, in step d) ito film with a thickness of 0.1-0.13。
Preferably, the vapor deposition temperature of ito film is 220 DEG C -300 DEG C in step d).
Preferably, the annealing temperature of ito film is 450-550 DEG C in step e).
The beneficial effects of the present invention are: by first growing one layer on the face reversed polarity AlGaInP quaternary LED epitaxial wafer P
SiO2Film, then apply negative photo glue-line on surface and pass through conventional lithographic for the SiO of P surface current extended area2It erodes, then passes through
The method of negative photoresist removing obtains the P surface current extension layer of ITO, then can be with the face P GaP by high annealing ito thin film
Forming good Ohmic contact also can make the extension of P surface current more preferable, obtain the reversed polarity AlGaInP quaternary LED core of more high photosynthetic efficiency
Piece improves the quality of chip.Pass through conventional SiO2Film growth and negative photoresist stripping means obtain the face the P electricity of ito film
Extension layer is flowed, ito film is made by high annealing and the face P GaP forms good Ohmic contact, it is easy to operate and can obtain more stable
Light-out effect, be suitble to large-scale production.
Detailed description of the invention
Fig. 1 is the schematic diagram of the section structure of reversed polarity quaternary LED chip of the invention；
Fig. 2 is the schematic diagram of the section structure of reversed polarity quaternary LED chip made from step a) of the invention；
Fig. 3 is the schematic diagram of the section structure of reversed polarity quaternary LED chip made from step b) of the invention；
In figure, 2. GaP layers of 4.SiO2 film of reversed polarity quaternary epitaxial layer 3.P type of 1.GaAs substrate, 5. negative photo glue-line
6.ITO film.
Specific embodiment
With reference to the accompanying drawing 1, the present invention will be further described for attached drawing 2.
The face the P ohmic contact layer of reversed polarity quaternary LED a kind of and the preparation method of current extending, include the following steps:
A) the reversed polarity AlGaInP quaternary LED extension of reversed polarity quaternary epitaxial layer 2 is grown on being completed in GaAs substrate 1
One layer is grown on the p-type GaP layer 3 of pieceFilm；
B) in reversed polarity AlGaInP quaternary LED epitaxial waferNegative photoresist is applied on film, forms negative photo glue-line 5；
C) it is etched on negative photo glue-line 5 by photoetching and forms current expansion figure, corrode the electricity on 3 upper surface of p-type GaP layer
In stream extension figureFilm；
D) one layer of ito film 6 is deposited by way of electron beam evaporation plating in reversed polarity AlGaInP quaternary LED epitaxial wafer, passes through
Negative photoresist stripping technology removes the ito film 6 except the current expansion figure on 3 upper surface of p-type GaP layer；
E) ito film 6 in the current expansion figure on 3 upper surface of p-type GaP layer is subjected to high annealing, on p-type GaP layer 3
The face P ohmic contact layer and current extending is made.
In the prior art, the current extending on the p-type GaP layer 3 of reversed polarity AlGaInP quaternary LED chip be all using
Au film, Au, which can form good Ohmic contact with GaP layers of the face P but also result in part and go out light, to be stopped and is absorbed by Au film
The present invention on the face reversed polarity AlGaInP quaternary LED epitaxial wafer P by first growing one layer of SiO2Film 4, then apply and bear on surface
Property photoresist layer 5 by conventional lithographic by the SiO of P surface current extended area2It erodes, then the side removed by negative photoresist
Method obtains the P surface current extension layer of ITO, then can form good Ohmic contact with the face P GaP by high annealing ito thin film
Also the extension of P surface current can be made more preferable, the reversed polarity AlGaInP quaternary LED chip of more high photosynthetic efficiency is obtained, improve the product of chip
Matter.Pass through conventional SiO2Film growth and negative photoresist stripping means obtain the P surface current extension layer of ito film, pass through high temperature
Annealing makes ito film and the face P GaP forms good Ohmic contact, easy to operate and can obtain more stable light-out effect, is suitble to rule
Modelling production.
Embodiment 1:
It is grown in step a) by the method for PECVD growthFilm.
Embodiment 2:
In step a)Film with a thickness of 0.3-0.4。
Embodiment 3:
Negative photo glue-line 5 with a thickness of 1.5-3 in step b)。
Embodiment 4:
In current expansion figure in step c) on corrosion 3 upper surface of p-type GaP layerThe step of film are as follows:
C-1 the hydrofluoric acid and pure water that the ammonium fluoride solution for being) 96% using concentration, content are 40% are 3 according to mass volume ratio:
The proportional arrangement of 6:18 or 3:9:18Corrosive liquid；
C-2) reversed polarity AlGaInP quaternary LED epitaxial wafer is placed inIt is carried out in corrosive liquidCorrosion, by negative photoresist
The SiO2 film 4 that layer 5 exposes is corroded.
Embodiment 5:
In step c)The etching time of film is 1-2 minutes.
Embodiment 6:
Current expansion figure in step c) is cylindrical or linear structure.
Embodiment 7:
Ito film 6 with a thickness of 0.1-0.13 in step d)。
Embodiment 8:
The vapor deposition temperature of ito film 6 is 220 DEG C -300 DEG C in step d).
Embodiment 9:
The annealing temperature of ito film 6 is 450-550 DEG C in step e).
Claims (10)
1. the face the P ohmic contact layer of reversed polarity quaternary LED a kind of and the preparation method of current extending, which is characterized in that including
Following steps:
A) the reversed polarity AlGaInP quaternary LED of reversed polarity quaternary epitaxial layer (2) is grown on being completed in GaAs substrate (1)
One layer is grown on GaP layers of p-type (3) of epitaxial waferFilm；
B) in reversed polarity AlGaInP quaternary LED epitaxial waferNegative photoresist is applied on film, is formed negative photo glue-line (5)；
C) it is etched on negative photo glue-line (5) by photoetching and forms current expansion figure, corroded on p-type GaP layers of (3) upper surface
Current expansion figure inFilm；
D) one layer of ito film (6) is deposited by way of electron beam evaporation plating in reversed polarity AlGaInP quaternary LED epitaxial wafer, leads to
Negative photoresist stripping technology is crossed to remove the ito film (6) except the current expansion figure on GaP layers of p-type (3) upper surface；
E) ito film (6) in the current expansion figure on GaP layers of p-type (3) upper surface is subjected to high annealing, at GaP layers of p-type
(3) face P ohmic contact layer and current extending are made on.
2. the face the P ohmic contact layer of reversed polarity quaternary LED according to claim 1 and the preparation method of current extending,
It is characterized by: being grown in step a) by the method for PECVD growthFilm.
3. the face the P ohmic contact layer of reversed polarity quaternary LED according to claim 1 and the preparation method of current extending,
It is characterized by: in step a)Film with a thickness of 0.3-0.4。
4. the face the P ohmic contact layer of reversed polarity quaternary LED according to claim 1 and the preparation method of current extending,
It is characterized by: in step b) negative photo glue-line (5) with a thickness of 1.5-3。
5. the face the P ohmic contact layer of reversed polarity quaternary LED according to claim 1 and the preparation method of current extending,
It is characterized in that, corroding in the current expansion figure on p-type GaP layers of (3) upper surface in step c)The step of film are as follows:
C-1 the hydrofluoric acid and pure water that the ammonium fluoride solution for being) 96% using concentration, content are 40% are 3 according to mass volume ratio:
The proportional arrangement of 6:18 or 3:9:18Corrosive liquid；
C-2) reversed polarity AlGaInP quaternary LED epitaxial wafer is placed inIt is carried out in corrosive liquidCorrosion, by negative photoresist
The SiO2 film (4) that layer (5) exposes is corroded.
6. the face the P ohmic contact layer of reversed polarity quaternary LED according to claim 1 and the preparation method of current extending,
It is characterized by: in step c)The etching time of film is 1-2 minutes.
7. the face the P ohmic contact layer of reversed polarity quaternary LED according to claim 1 and the preparation method of current extending,
It is characterized by: the current expansion figure in step c) is cylindrical or linear structure.
8. the face the P ohmic contact layer of reversed polarity quaternary LED according to claim 1 and the preparation method of current extending,
It is characterized by: in step d) ito film (6) with a thickness of 0.1-0.13。
9. the face the P ohmic contact layer of reversed polarity quaternary LED according to claim 1 and the preparation method of current extending,
It is characterized by: the vapor deposition temperature of ito film (6) is 220 DEG C -300 DEG C in step d).
10. the face the P ohmic contact layer of reversed polarity quaternary LED according to claim 1 and the preparation method of current extending,
It is characterized by: the annealing temperature of ito film (6) is 450-550 DEG C in step e).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711189562.5A CN109841713A (en) | 2017-11-24 | 2017-11-24 | The face the P ohmic contact layer of reversed polarity quaternary LED and the preparation method of current extending |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711189562.5A CN109841713A (en) | 2017-11-24 | 2017-11-24 | The face the P ohmic contact layer of reversed polarity quaternary LED and the preparation method of current extending |
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| Publication Number | Publication Date |
|---|---|
| CN109841713A true CN109841713A (en) | 2019-06-04 |
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ID=66876108
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711189562.5A Pending CN109841713A (en) | 2017-11-24 | 2017-11-24 | The face the P ohmic contact layer of reversed polarity quaternary LED and the preparation method of current extending |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115207182A (en) * | 2022-09-15 | 2022-10-18 | 南昌凯捷半导体科技有限公司 | Red light mini LED with P-surface thin film conducting layer and preparation method thereof |
-
2017
- 2017-11-24 CN CN201711189562.5A patent/CN109841713A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115207182A (en) * | 2022-09-15 | 2022-10-18 | 南昌凯捷半导体科技有限公司 | Red light mini LED with P-surface thin film conducting layer and preparation method thereof |
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