CN109742203A - A kind of iii-nitride light emitting devices - Google Patents
A kind of iii-nitride light emitting devices Download PDFInfo
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- CN109742203A CN109742203A CN201910032647.5A CN201910032647A CN109742203A CN 109742203 A CN109742203 A CN 109742203A CN 201910032647 A CN201910032647 A CN 201910032647A CN 109742203 A CN109742203 A CN 109742203A
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Abstract
The invention discloses a kind of iii-nitride light emitting devices, including a substrate, and it is sequentially located at n-type semiconductor layer, active layer, electronic barrier layer, p-type semiconductor layer and P type contact layer on substrate, it is characterized by: the p-type semiconductor layer includes the hole injection layer and hole diffusion layer being successively set on electronic barrier layer, the hole injection layer and P type contact layer are all the highly doped nitride layer of Mg and C codope, and the hole diffusion layer is the low-mix nitride layer containing Al.The present invention has the advantages that hole injection layer and P type contact layer all use the form of Mg and C codope, hole concentration can be improved, the luminous efficiency and operating voltage of light emitting diode are improved to avoid self-compensation mechanism caused by Mg overdoping;In addition, being inserted into the low-doped nitride layer containing aluminium between highly doped hole injection layer and P type contact layer as hole diffusion layer, hole sideways diffusion ability can be improved, and promote the internal quantum efficiency of light emitting diode.
Description
Technical field
The present invention relates to technical field of semiconductors more particularly to a kind of iii-nitride light emitting devices.
Background technique
Light emitting diode (Light emitting diodes, LED) is a kind of electroluminescent device, has energy conservation, ring
Guarantor, the advantages that safety, the service life is long, low in energy consumption, brightness is high, waterproof, miniature, light beam are concentrated, easy maintenance, are widely used in friendship
The fields such as ventilating signal lamp, street lamp and large-area displays.The especially fast development of gallium nitride (GaN) based light-emitting diode, with
White-light illuminating based on blue light-emitting diode more becomes current research hotspot.
The epitaxial structure of current gallium nitride based light emitting diode includes n-type semiconductor layer, active layer, p-type semiconductor layer
And P type contact layer.Wherein the n-type dopant and p-type dopant of gallium nitride-based semiconductor are respectively silicon (Si) and magnesium (Mg), and
Activation energy of the Si and Mg in gallium nitride is respectively 17meV and 270meV, this means (thermal energy 26meV) at room temperature,
The n-type doping of gallium nitride is easy to may be implemented, but the p-type doping of gallium nitride is then not easily accomplished, and which results in current nitrogen
Change in gallium based light-emitting diode, because the hole concentration of p-type layer is relatively low, causes light-emitting diode luminous efficiency relatively low and work electricity
Press higher problem.
Summary of the invention
(1) the technical issues of solving
In view of the deficiencies of the prior art, it the present invention provides a kind of iii-nitride light emitting devices, solves in the prior art, nitridation
The p-type doping of gallium is not easily accomplished, and causes the hole concentration of p-type layer relatively low, causes light-emitting diode luminous efficiency relatively low and work
Make the higher problem of voltage.
(2) technical solution
In order to achieve the object, the invention provides the following technical scheme: a kind of iii-nitride light emitting devices, including a substrate, with
And it is sequentially located at n-type semiconductor layer, active layer, electronic barrier layer, p-type semiconductor layer and P type contact layer on substrate, feature
Be: the p-type semiconductor layer includes the hole injection layer and hole diffusion layer being successively set on electronic barrier layer, the sky
Cave implanted layer is the highly doped nitride layer of Mg and C codope, and the doping concentration of the Mg and C of the hole injection layer are respectively greater than
5E19cm-3And 5E17cm-3, the hole diffusion layer is the low-mix nitride layer containing Al.
Wherein: the P type contact layer is the highly doped nitride layer of Mg and C codope, in the P type contact layer, Mg and C's
The maximum value of doping concentration is respectively greater than 1E20cm-3And 1E18cm-3。
Wherein: the band gap width of the hole diffusion layer is greater than the band gap width of hole injection layer and P type contact layer.
Wherein: the hole diffusion layer is p-type AlGaN, and with a thickness of 10 ~ 50nm, it is dense that Al group is divided into 0.05 ~ 0.5, Mg doping
Degree is less than 2E19cm-3。
Wherein: the n-type semiconductor layer is N-shaped GaN, and with a thickness of 1 ~ 5 μm, Si doping concentration is 5E18 ~ 1E20cm-3。
Wherein: the active layer is that several InGaN potential well layers and AlGaN potential barrier are alternately stacked the multiple quantum wells to be formed
Structure, InGaN potential well layer with a thickness of 1 ~ 5nm, AlGaN potential barrier with a thickness of 5 ~ 15nm.
Wherein: the electronic barrier layer is AlN or AlGaN, with a thickness of 1 ~ 10nm.
Wherein: the hole injection layer is GaN, with a thickness of 10 ~ 100nm.
Wherein: the P type contact layer is GaN, with a thickness of 6 ~ 60nm.
Wherein: the substrate is sapphire (Al2O3) substrate, silicon (Si) substrate, silicon carbide (SiC) substrate, aluminium nitride
(AlN) substrate, gallium nitride (GaN) substrate, gallium oxide (Ga2O3) any one in substrate or zinc oxide (ZnO) substrate.
Wherein: the n-type semiconductor layer before growth can preferred growth buffer layer or stress release layer to alleviate N-shaped half
Lattice mismatch between conductor layer and substrate.
Wherein: the doping concentration of Mg and C can be fixed value or be to increase along epitaxial growth direction in the P type contact layer,
When the doping concentration of Mg and C is to increase along epitaxial growth direction, near the Mg and C of epi-layer surface in P type contact layer
Doping concentration highest is conducive to the production of p-type electrode ohmic contact in subsequent chip processing procedure.
(3) beneficial effect
Compared with prior art, the present invention provides a kind of iii-nitride light emitting devices, have following the utility model has the advantages that firstly, empty
Cave implanted layer and P type contact layer all use the form of Mg and C codope, can imitate to avoid self compensation caused by Mg overdoping
Answer, improve hole concentration, can increase active layer in light emitting diode hole injection, improve light emitting diode luminous efficiency and
Operating voltage;In addition, being inserted into the low-doped nitride layer conduct containing aluminium between highly doped hole injection layer and P type contact layer
Hole sideways diffusion ability can be improved in hole diffusion layer, improves the uniformity of current distribution in active layer, improves light-emitting diodes
The internal quantum efficiency of pipe.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of the embodiment of the present invention.
Appended drawing reference:
Substrate 1, n-type semiconductor layer 2, active layer 3, electronic barrier layer 4, p-type semiconductor layer 5, hole injection layer 51, hole diffusion
Layer 52, P type contact layer 6.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
Embodiment 1, as shown in Figure 1, a kind of iii-nitride light emitting devices, an including substrate 1, and be sequentially located at substrate 1
On n-type semiconductor layer 2, active layer 3, electronic barrier layer 4, p-type semiconductor layer 5 and P type contact layer 6, in which: the p-type half
Conductor layer 5 includes the hole injection layer 51 and hole diffusion layer 52 being successively set on electronic barrier layer 4, the hole injection layer
51 and P type contact layer 6 be all Mg and C codope highly doped nitride layer, the hole diffusion layer 52 be containing aluminium low-mix nitridation
Nitride layer.
Specifically, the substrate 1 is sapphire (Al2O3) substrate, silicon (Si) substrate, silicon carbide (SiC) substrate, aluminium nitride
(AlN) substrate, gallium nitride (GaN) substrate, gallium oxide (Ga2O3) any one in substrate or zinc oxide (ZnO) substrate.This reality
Apply the preferred sapphire of example.
Specifically, the n-type semiconductor layer 2 is the GaN of Si doping, with a thickness of 2.5 μm, doping concentration 5E19cm-3.It can
Selection of land, before growing the n-type semiconductor layer 2 can preferred growth buffer layer or stress release layer to alleviate n-type semiconductor layer
Lattice mismatch between substrate.
Specifically, the active layer 3 is that several InGaN potential well layers and AlGaN potential barrier are alternately stacked the volume to be formed
Sub- well structure, the periodicity of multiple quantum wells is 15 in the present embodiment, and potential well layer InGaN, wherein In group is divided into 0.14, with a thickness of
2.5nm, barrier layer GaN, with a thickness of 10nm.
Specifically, the electronic barrier layer 4 can be AlN or AlGaN, and the preferred AlN of the present embodiment is electronic barrier layer, thick
Degree is 2.5nm.
Specifically, the p-type semiconductor layer 5 includes hole injection layer 51 and hole diffusion layer 52, wherein hole injection layer
51 be the p-type GaN, Mg of Mg and C codope doping concentration be 1E20cm-3, the doping concentration of C is 7E17cm-3, with a thickness of
25nm;Hole diffusion layer 52 is the AlGaN of low-mix, and it is 5E18cm that wherein Al group, which is divided into 0.15, Mg doping concentration,-3, with a thickness of
30nm.The hole injection layer 51 carries out p-type doping by the way of Mg and C codope, it is possible to prevente effectively from Mg overdoping and
Caused self-compensation mechanism improves hole concentration, increases the hole injection in active layer, improves the luminous effect of light emitting diode
Rate;And hole diffusion layer 52 is the low-doped GaN layer of the component containing Al, energy gap is higher than hole injection layer 51 and P type contact layer
6, and the amount of Mg and C is below hole injection layer 51 and P type contact layer 6, resistance value is relative to hole injection layer 51 and p-type contact
Layer 6 is higher, is conducive to the sideways diffusion ability in hole, improves the uniformity of current distribution in active layer, improves light emitting diode
Internal quantum efficiency.
Specifically, it is 2E20cm that the P type contact layer 6, which is the doping concentration of the p-type GaN, Mg of Mg and C codope,-3, C's
Doping concentration is 2E18cm-3, with a thickness of 3nm.The P type contact layer 6 can be improved p-type by the way of Mg and C codope and connect
Hole concentration in contact layer, to reduce the operating voltage of light emitting diode.
The foregoing is only a preferred embodiment of the present invention, is not intended to restrict the invention, for the skill of this field
For art personnel, the invention may be variously modified and varied.All within the spirits and principles of the present invention, made any to repair
Change, equivalent replacement, improvement etc., should all be included in the protection scope of the present invention.
Claims (10)
1. a kind of iii-nitride light emitting devices, including a substrate, and be sequentially located on substrate n-type semiconductor layer, active layer,
Electronic barrier layer, p-type semiconductor layer and P type contact layer, it is characterised in that: the p-type semiconductor layer includes to be successively set on electricity
Hole injection layer and hole diffusion layer on sub- barrier layer, the hole injection layer are the highly doped nitride layer of Mg and C codope,
The doping concentration of the Mg and C of the hole injection layer are respectively greater than 5E19cm-3And 5E17cm-3, the hole diffusion layer is containing Al
Low-mix nitride layer.
2. a kind of iii-nitride light emitting devices according to claim 1, it is characterised in that: the P type contact layer is Mg and C
The highly doped nitride layer of codope, in the P type contact layer, the maximum value of the doping concentration of Mg and C is respectively greater than 1E20cm-3With
1E18cm-3。
3. a kind of iii-nitride light emitting devices according to claim 1, it is characterised in that: the band gap of the hole diffusion layer
Width is greater than the band gap width of hole injection layer and P type contact layer.
4. a kind of iii-nitride light emitting devices according to claim 1, it is characterised in that: the hole diffusion layer is p-type
AlGaN, with a thickness of 10 ~ 50nm, Al group is divided into 0.05 ~ 0.5, Mg doping concentration less than 2E19cm-3。
5. a kind of iii-nitride light emitting devices according to claim 1, it is characterised in that: the n-type semiconductor layer is N-shaped
GaN, with a thickness of 1 ~ 5 μm, Si doping concentration is 5E18 ~ 1E20cm-3。
6. a kind of iii-nitride light emitting devices according to claim 1, it is characterised in that: the active layer is several
InGaN potential well layer and AlGaN potential barrier are alternately stacked the multi-quantum pit structure to be formed, InGaN potential well layer with a thickness of 1 ~ 5nm,
AlGaN potential barrier with a thickness of 5 ~ 15nm.
7. a kind of iii-nitride light emitting devices according to claim 1, it is characterised in that: the electronic barrier layer is AlN
Or AlGaN, with a thickness of 1 ~ 10nm.
8. a kind of iii-nitride light emitting devices according to claim 1, it is characterised in that: the hole injection layer is GaN,
With a thickness of 10 ~ 100nm.
9. a kind of iii-nitride light emitting devices according to claim 1, it is characterised in that: the P type contact layer is GaN,
With a thickness of 6 ~ 60nm.
10. a kind of iii-nitride light emitting devices according to claim 1, it is characterised in that: the substrate is sapphire
(Al2O3) substrate, silicon (Si) substrate, silicon carbide (SiC) substrate, aluminium nitride (AlN) substrate, gallium nitride (GaN) substrate, gallium oxide
(Ga2O3) any one in substrate or zinc oxide (ZnO) substrate.
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CN113013301A (en) * | 2021-04-08 | 2021-06-22 | 厦门三安光电有限公司 | Nitride light emitting diode |
CN113808980A (en) * | 2020-09-30 | 2021-12-17 | 深圳市晶相技术有限公司 | Semiconductor epitaxial structure and application thereof |
CN113851927A (en) * | 2021-09-18 | 2021-12-28 | 常州纵慧芯光半导体科技有限公司 | Semiconductor laser |
CN113964246A (en) * | 2021-09-28 | 2022-01-21 | 厦门士兰明镓化合物半导体有限公司 | Epitaxial structure of light emitting diode and manufacturing method thereof |
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CN113808980A (en) * | 2020-09-30 | 2021-12-17 | 深圳市晶相技术有限公司 | Semiconductor epitaxial structure and application thereof |
CN112951961A (en) * | 2021-02-08 | 2021-06-11 | 江西乾照光电有限公司 | Deep ultraviolet LED and manufacturing method thereof |
CN113013301A (en) * | 2021-04-08 | 2021-06-22 | 厦门三安光电有限公司 | Nitride light emitting diode |
CN113851927A (en) * | 2021-09-18 | 2021-12-28 | 常州纵慧芯光半导体科技有限公司 | Semiconductor laser |
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CN113964246A (en) * | 2021-09-28 | 2022-01-21 | 厦门士兰明镓化合物半导体有限公司 | Epitaxial structure of light emitting diode and manufacturing method thereof |
CN113964246B (en) * | 2021-09-28 | 2024-05-31 | 厦门士兰明镓化合物半导体有限公司 | Epitaxial structure of light-emitting diode and manufacturing method thereof |
CN115132892A (en) * | 2021-12-30 | 2022-09-30 | 淮安澳洋顺昌光电技术有限公司 | Light emitting diode epitaxial structure and light emitting diode |
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