CN101290965B - Semiconductor light-emitting diode of III-nitrides - Google Patents
Semiconductor light-emitting diode of III-nitrides Download PDFInfo
- Publication number
- CN101290965B CN101290965B CN2008101147154A CN200810114715A CN101290965B CN 101290965 B CN101290965 B CN 101290965B CN 2008101147154 A CN2008101147154 A CN 2008101147154A CN 200810114715 A CN200810114715 A CN 200810114715A CN 101290965 B CN101290965 B CN 101290965B
- Authority
- CN
- China
- Prior art keywords
- barrier layer
- layer
- emitting diode
- quantum well
- gan
- 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
Images
Abstract
The invention relates to a 'group III nitride compound semiconductor light emitting diode', belonging to the compound semiconductor technical field. An active layer of the group III nitride compound semiconductor light emitting diode has a quantum-well structure with magnetic field inside. The quantum-well structure consists of a first barrier layer positioned on one side of a p-type region, a quantum-well layer, and a second barrier layer positioned on one side of an n-type region. The group III nitride compound semiconductor light emitting diode is characterized in that a third barrier layeris inserted into the quantum-well layer. The thickness of the third barrier layer meets the following conditions: (1) holes injected from the p-type region can be shielded between the third barrier layer and the first barrier layer position on one side of the p-type region; (2) electrons injected from the n-type region can freely pass through the third barrier layer and move toward a region withlowest energy. With the insertion of the third barrier layer, the space overlap of valve functions of the electrons and the holes as well as the recombination efficiency of light emission is increasedby one to two times.
Description
Technical field
The invention belongs to the compound semiconductor technical field, is about being material LED with the III group-III nitride semiconductor.
Background technology
With the III group-III nitride semiconductor is the blueness and the green LED of material, owing to be expected to replace existing incandescent lamp or fluorescent lamp becomes a kind of efficient height, long general lighting light source of life-span, and be subjected to countries in the world research and development personnel's great attention.Semiconductor light-emitting-diode is to utilize from n-type doped region injected electrons and carry out luminous compound and luminous in the active layer that is sandwiched in n-type doped region and p-type doped region from p-type doped region injected holes.Therefore the luminous recombination probability in electronics and hole is big more, and the luminous efficiency of semiconductor light-emitting-diode is that internal quantum is just high more.The energy conversion efficiency of light-emitting diode equals the outside of internal quantum and light and takes out the product of efficient.Internal quantum generally by the quality decision of crystal, has had the raising of leap recently along with the progressive internal quantum of crystal technique.For example, for the blue LED that is of a size of 300 μ mx300 μ m, under the low current condition of work of 20mA, its internal quantum can reach more than 50% at an easy rate.But, realize the universalness of general lighting device, also exist some and internal quantum to improve relevant problems that must solve.Specifically, surpassing under the big current work condition of 20mA and the green wavelength section, internal quantum sharply reduces.Causing one of main reason that internal quantum descends in these fields is to have internal electric field in the active layer.
Blue and green LED generally is to utilize the organic metal vapour phase epitaxy method on the Sapphire Substrate of (0001) face (or c face) growing n-type layer, quantum well active layer and p type layer form successively.In this case, on the direction of growth, there is the powerful internal electric field that causes by piezoelectric effect and self poling effect.For example, with GaN/In
0.15Ga
0.85The N quantum well is in the blue LED of active layer, and the intensity of its internal electric field can reach 1MV/cm.As Fig. 1 (GaN/In
0.15Ga
0.85The band structure schematic diagram of N (3nm)/GaN quantum well and the wave function of Theoretical Calculation) shown in, wherein 1 is electronic band structure, 2 is the band structure in hole, 3 is the wave function of electronics, 4-is the wave function in hole, and 5 is the GaN barrier layer, and 6 is the thick In of 3nm
0.15Ga
0.85The N quantum well layer, 7 is the GaN barrier layer, owing to there is so strong internal electric field, the electronics of quantum well spatially separates with the wave function in hole 3,4, thereby causes luminous compounding efficiency significantly to reduce.In addition, the intensity of internal electric field strengthens along with the increase of In component, and in the component of In must reach green LED more than 0.25, the influence of internal electric field was then more remarkable.
Basically there are two kinds of methods to utilize at present, with the reduction of the internal quantum that suppresses to cause owing to internal electric field.First method is to reduce the thickness of quantum well layer, the space overlap part of the wave function in pressure increase electronics and hole.But the thickness of quantum well layer is too thin, and wave function can infiltrate barrier layer, and luminous combined efficiency is descended.By considering the balance of wave function between the inhibition effect of the apart of the infiltration of barrier layer and wave function, the thickness of quantum well layer is generally 3nm for the device of practicability.But as shown in Figure 1, even for the quantum well layer that has only 3nm thickness, the apart of the wave function in electronics and hole is still very strong.Second method is to use c-surface sapphire substrate in addition, thereby do not have the crystal of polarity in direction of growth growth.Up to the present, (11-02) face (or r-face) sapphire, (101-0) face (or m-face) sapphire, γ-LiAlO have been attempted
2And substrate such as GaN.The crystal of comparing and growing on the c-surface sapphire is at r-surface sapphire, m-surface sapphire and γ-LiAlO
2Want inferior many Deng the quality of the crystallization of growing on the xenogenesis substrate, also do not reach the level of practicability far away.In addition, the GaN substrate is very expensive, is more than 10 times of Sapphire Substrate price, also can not realize large-scale application now.
Summary of the invention
At the defective in the above-mentioned field, the invention provides a kind of quantum well structure that adopts is the III group-III nitride semiconductor light-emitting diode of active layer, this quantum well active layer can greatly suppress the apart of the wave function in electronics that the existence because of internal electric field causes and hole, thereby effectively improves the luminous combined efficiency of active layer.
III group-III nitride semiconductor light-emitting diode, its active layer is the quantum well structure that has internal electric field, described quantum well structure active layer is by first barrier layer, the quantum well layer that are positioned at p type zone one side and be positioned at that second barrier layer of n type zone one side constituted, it is characterized in that: insert the 3rd barrier layer in the described quantum well layer, the thickness of described the 3rd barrier layer meets the following conditions: (1) can be shielded in the 3rd barrier layer with between first barrier layer of the regional side of p type by p type zone injected holes; (2) can freely pass through the 3rd barrier layer by n type zone injected electrons, move to the zone that energy is minimum.
Described the 3rd barrier layer is Al
xGa
1-xN (0≤x≤0.2) or In
xGa
1-xN (x＜0.1), thickness is 0.5nm-2nm.
Described first barrier layer is Al
xGa
1-xN (0≤x≤0.2).
Described second barrier layer is Al
xGa
1-xN (0≤x≤0.2).
Described quantum well layer is In
xGa
1-xN (0.1≤x≤0.5).
Described first barrier layer, quantum well layer, second barrier layer are respectively Al
xGa
1-xN (0≤x≤0.2), In
xGa
1-xN (0.1≤x≤0.5), Al
xGa
1-xN (0≤x≤0.2); The 3rd barrier layer of aforementioned insertion is GaN, and the thickness of this layer is 1nm.
Described the 3rd barrier layer insertion position is the place between distance first barrier layer 0.5nm ~ 2.5nm.
According to III group-III nitride semiconductor light-emitting diode of the present invention, in the trap layer of the quantum well structure active layer that has strong internal electric field, insert i.e. the 3rd barrier layer of one deck barrier layer, by adjusting the thickness of this barrier layer, make this barrier layer can bring into play the effect of barrier layer and electronics is not brought into play substantially the effect of barrier layer the hole.For this structure,, and accumulate in the near interface (electron energy is minimum) that is positioned at the regional side of p type of quantum well layer herein by n type zone injected electrons whole the 3rd barrier layer by above-mentioned insertion basically; And by the insertion of p type zone injected holes owing to above-mentioned the 3rd barrier layer, be shielded in the 3rd barrier layer and the quantum well layer between the barrier layer of p type zone one side of insertion.Therefore, the space overlap of the wave function in electronics and hole partly increases, and makes to suppress to cause luminous combined efficiency to be declined to become possibility owing to internal electric field causes the apart of electronics and hole wave function.
If the 3rd barrier layer that inserts too thin (hole can not conductively-closed) or too thick (electronics can not move to low energy area), the insertion of the 3rd barrier layer can not be brought into play the effect that suppresses the wave function apart.Use under the situation of GaN as the 3rd barrier layer, the thickness of GaN preferably is controlled in the 0.5nm-2.0nm scope.Moreover, if the ground floor barrier layer 2.5nm that is positioned at p type zone one side in distance with the place insert the 3rd barrier layer, preferred distance is the place of 0.5nm ~ 2.5nm, compare with the general 3nm quantum well that adopts in the common commercially available device, can expect to suppress significantly the effect of wave function apart.
As blue LED, its first barrier layer is GaN, and second barrier layer is GaN, and quantum well layer is In
0.15Ga
0.85N, the 3rd barrier layer are GaN, and thickness is 1nm, and substrate is (0001) face (C face) sapphire.
As green LED, its first barrier layer is GaN, and second barrier layer is GaN, and quantum well layer is In
0.3Ga
0.7N, the 3rd barrier layer are GaN, and thickness is 1nm, and substrate is (0001) face (C face) sapphire.
Prove by experiment, the present invention inserts the 3rd barrier layer in quantum well layer, make the overlapping increase of electronics and hole function, luminous combined efficiency increases, from embodiments of the invention, its luminous combined efficiency is to insert the 3rd barrier layer 2-3 before doubly, has improved the luminous efficiency of III group-III nitride light-emitting diode greatly.
Description of drawings
Fig. 1 GaN/In
0.15Ga
0.85The band structure schematic diagram of N (3nm)/GaN quantum well and the wave function of Theoretical Calculation
The sectional schematic diagram of the crystal structure of Fig. 2 embodiment of the invention 1III group-III nitride light-emitting diode.
The band structure schematic diagram of the active layer of Fig. 3 embodiment of the invention 1III group-III nitride light-emitting diode and the wave function of Theoretical Calculation.
The sectional schematic diagram of the crystal structure of Fig. 4 embodiment of the invention 2III group-III nitride light-emitting diode.
Wherein: 1---electronic band structure, the band structure in 2---hole, the wave function of 3---electronics, the wave function in 4---hole, 5---GaN barrier layer, the In that 6---3nm is thick
0.15Ga
0.85The N quantum well layer, 7---GaN barrier layer, 8---(0001) surface sapphire substrate, 9---low temperature GaN resilient coating, the 10---Si doped n type GaN high temperature buffer layer and second barrier layer, the In that 11---3nm is thick
0.15Ga
0.85The N quantum well layer, GaN the 3rd barrier layer that 12---1nm is thick, the In that 13---2nm is thick
0.15Ga
0.85The N quantum well layer, 14---GaN first barrier layer, 15---Mg doped p type Al
0.2Ga
0.8The N electronic barrier layer, 16---Mg doped p type GaN ohmic contact layer, 17---electronic band structure, the band structure in 18---hole, the wave function of 19---electronics, the wave function in 20---hole, the In that 21---3nm is thick
0.3Ga
0.7The N quantum well layer, GaN the 3rd barrier layer that 22---1nm is thick, the In that 23---2nm is thick
0.3Ga
0.7The N quantum well layer.
Embodiment
At first, on (0001) surface sapphire substrate 8, utilize the organic metal vapour phase epitaxy method, at 550 ℃ of thick low temperature GaN resilient coatings 9 of growth one deck 40nm.Then, temperature is risen to 1040 ℃, growth thickness is Si doped n type GaN (n=2 * 10 of 4 μ m
18Cm
-3) as the high temperature buffer layer and second barrier layer 10.Then, reduce growth temperature to about 760 ℃, growth thickness is the undoped In of 3nm successively
0.15Ga
0.85N quantum well layer 11, thickness are that undoped GaN the 3rd barrier layer 12, the thickness of 1nm is the undoped In of 2nm
0.15Ga
0.85N quantum well layer 13, and thickness is undoped GaN first barrier layer 14 of 20nm.At last, growth temperature is risen to 1040 ℃, the layer thickness of growing is the Mg doped p type Al of 10nm
0.2Ga
0.8A N electronic barrier layer 15 and a layer thickness are the Mg doped p type GaN ohmic contact layer 16 of 150nm.Structure chart is seen Fig. 2.
Fig. 3 has provided the band structure of the quantum well active layer in the light emitting diode construction shown in Figure 2 and the wave function of Theoretical Calculation.Wherein 17 is electronic band structure, and 18 is the band structure in hole, and 19 is the wave function of electronics, and 20 is the wave function in hole, and 21 is the thick In of 3nm
0.3Ga
0.7The N quantum well layer, 22 is the thick GaN of 1nm the 3rd barrier layer, 23 is the thick In of 2nm
0.3Ga
0.7The N quantum well layer.Compare with the 3nm quantum well structure of Fig. 1, can be clear that the peak position of the wave function 19,20 in electronics and hole becomes close, the space overlap of wave function has increased.Utilize the wave function of Fig. 3 can calculate the space overlap integration in electronics and hole, that is: ∫ φ
eφ
hDz is at this φ
eAnd φ
hBe respectively the wave function in electronics and hole, z is the coordinate of crystal growth direction.And square being directly proportional of the space overlap integration of the luminous combined efficiency in electronics and hole and above-mentioned wave function.The 3nm quantum well structure that does not have the 3rd barrier layer that the luminous combined efficiency that can calculate the quantum well structure active layer of Fig. 3 thus is about Fig. 1 is GaN/In
0.15Ga
0.852.2 times of N (3nm)/GaN quantum well structure.
At first, on (0001) surface sapphire substrate 8, utilize the organic metal vapour phase epitaxy method, at 550 ℃ of thick low temperature GaN resilient coatings 9 of growth one deck 40nm.Then, temperature is risen to 1040 ℃, growth thickness is Si doped n type GaN (n=2 * 10 of 4 μ m
18Cm
-3) as the high temperature buffer layer and second barrier layer 10.Then, reduce growth temperature to about 760 ℃, growth thickness is the undoped In of 3nm successively
0.3Ga
0.7N quantum well layer 11, thickness are that undoped GaN the 3rd barrier layer 12, the thickness of 1nm is the undoped In of 2nm
0.3Ga
0.7N quantum well layer 13, and thickness is undoped GaN first barrier layer 14 of 20nm.At last, growth temperature is risen to 1040 ℃, the layer thickness of growing is the Mg doped p type Al of 10nm
0.2Ga
0.8A N electronic barrier layer 15 and a layer thickness are the Mg doped p type GaN ohmic contact layer 16 of 150nm.Structure chart is seen Fig. 4.
Being used for embodiment 1 identical method can calculate the luminous combined efficiency of the quantum well structure active layer of light-emitting diode shown in Figure 4 and be about that not have the 3nm of the 3rd barrier layer quantum well structure be GaN/In
0.3Ga
0.73.1 times of N (3nm)/GaN quantum well structure.This shows that method of the present invention is more obvious for stronger its effect of green light LED of internal electric field.
Claims (9)
1.III group-III nitride semiconductor light-emitting diode, its active layer is the quantum well structure that has internal electric field, described quantum well structure active layer is by first barrier layer, the quantum well layer that are positioned at p type zone one side and be positioned at that second barrier layer of n type zone one side constituted, it is characterized in that: insert the 3rd barrier layer in the described quantum well layer, the thickness of described the 3rd barrier layer meets the following conditions: (1) can be shielded in the 3rd barrier layer with between first barrier layer of the regional side of p type by p type zone injected holes; (2) can freely pass through the 3rd barrier layer by n type zone injected electrons, move to the zone that energy is minimum.
2. III group-III nitride semiconductor light-emitting diode according to claim 1, described the 3rd barrier layer is Al
xGa
1-xN, 0≤x≤0.2; Or In
xGa
1-xN, x＜0.1; Thickness is 0.5nm-2nm.
3. III group-III nitride semiconductor light-emitting diode according to claim 2, described first barrier layer is Al
xGa
1-xN, 0≤x≤0.2.
4. III group-III nitride semiconductor light-emitting diode according to claim 2, described second barrier layer is Al
xGa
1-xN, 0≤x≤0.2.
5. III group-III nitride semiconductor light-emitting diode according to claim 2, described quantum well layer is In
xGa
1-xN, 0.1≤x≤0.5.
6. III group-III nitride semiconductor light-emitting diode according to claim 2, described first barrier layer, quantum well layer, second barrier layer are respectively Al
xGa
1-xN, 0≤x≤0.2; In
xGa
1-xN, 0.1≤x≤0.5; Al
xGa
1-xN, 0≤x≤0.2; The 3rd barrier layer of aforementioned insertion is GaN, and the thickness of this layer is 1nm.
7. III group-III nitride semiconductor light-emitting diode according to claim 6, described the 3rd barrier layer insertion position are the place between distance first barrier layer 0.5nm～2.5nm.
8. III group-III nitride semiconductor light-emitting diode according to claim 6, described first barrier layer is GaN, and second barrier layer is GaN, and quantum well layer is In
0.15Ga
0.85N, the 3rd barrier layer are GaN, and thickness is 1nm, and substrate is the C surface sapphire.
9. III group-III nitride semiconductor light-emitting diode according to claim 6, described first barrier layer is GaN, and second barrier layer is GaN, and quantum well layer is In
0.3Ga
0.7N, the 3rd barrier layer are GaN, and thickness is 1nm, and substrate is the C surface sapphire.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008101147154A CN101290965B (en) | 2008-06-11 | 2008-06-11 | Semiconductor light-emitting diode of III-nitrides |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008101147154A CN101290965B (en) | 2008-06-11 | 2008-06-11 | Semiconductor light-emitting diode of III-nitrides |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101290965A CN101290965A (en) | 2008-10-22 |
| CN101290965B true CN101290965B (en) | 2010-06-09 |
Family
ID=40035122
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2008101147154A Expired - Fee Related CN101290965B (en) | 2008-06-11 | 2008-06-11 | Semiconductor light-emitting diode of III-nitrides |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101290965B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4940317B2 (en) * | 2010-02-25 | 2012-05-30 | 株式会社東芝 | Semiconductor light emitting device and manufacturing method thereof |
| CN104253182B (en) * | 2013-06-26 | 2019-07-16 | 南通同方半导体有限公司 | A kind of blue-ray LED epitaxial structure with asymmetric barrier layer |
| CN103531683B (en) * | 2013-09-23 | 2016-06-22 | 华灿光电股份有限公司 | A kind of gallium nitride light-emitting diode and preparation method thereof |
| CN107170865B (en) * | 2017-05-27 | 2019-05-14 | 安徽三安光电有限公司 | A kind of semiconductor light-emitting elements and preparation method thereof |
-
2008
- 2008-06-11 CN CN2008101147154A patent/CN101290965B/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN101290965A (en) | 2008-10-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106784210B (en) | A kind of epitaxial wafer of light emitting diode and preparation method thereof | |
| CN102157656B (en) | Nitride light-emitting diode capable of enhancing carrier injection efficiency and manufacturing method thereof | |
| US20130214250A1 (en) | Nitride based semiconductor light-emitting device | |
| CN108461592B (en) | A kind of LED epitaxial slice and its manufacturing method | |
| CN106611808B (en) | A kind of growing method of LED epitaxial slice | |
| CN102157657A (en) | GaN-based light emitting diode and preparation method thereof | |
| KR20090117538A (en) | Nitride semiconductor light emitting device | |
| CN101359710A (en) | Manufacturing method of green light LED | |
| CN106449915B (en) | A kind of growing method of LED epitaxial slice | |
| CN102185056A (en) | Gallium-nitride-based light emitting diode capable of improving electron injection efficiency | |
| CN104022197B (en) | A kind of LED epitaxial slice and its manufacture method | |
| CN109192825B (en) | Light emitting diode epitaxial wafer and manufacturing method thereof | |
| US10580936B2 (en) | Group III nitride semiconductor light-emitting device and production method therefor | |
| CN101714602A (en) | Multiple quantum well structure for photoelectric device | |
| US8759815B2 (en) | Nitride based semiconductor light emitting device | |
| CN104576852A (en) | Stress regulation method for luminous quantum wells of GaN-based LED epitaxial structure | |
| CN109742203A (en) | A kind of iii-nitride light emitting devices | |
| TW201338197A (en) | Light emitting device with graded composition hole tunneling layer | |
| WO2021128810A1 (en) | Light-emitting diode and method for manufacturing same | |
| CN109449264A (en) | A kind of LED epitaxial slice and its manufacturing method | |
| CN101290965B (en) | Semiconductor light-emitting diode of III-nitrides | |
| CN109004074A (en) | LED epitaxial structure and preparation method thereof | |
| CN109103312B (en) | Gallium nitride-based light emitting diode epitaxial wafer and manufacturing method thereof | |
| CN102881790A (en) | LED quantum well structure and growth method | |
| CN208507715U (en) | LED epitaxial structure |
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 | ||
| DD01 | Delivery of document by public notice |
Addressee: Beijing Yuji Technology Development Co. Document name: Notification of Passing Examination on Formalities |
|
| DD01 | Delivery of document by public notice | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20100609 Termination date: 20210611 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |