KR102302855B1 - Light emitting device, and lighting system - Google Patents

Abstract

The embodiment relates to a light emitting device, a method of manufacturing a light emitting device, a light emitting device package, and a lighting system.
The light emitting device according to the embodiment includes a first conductivity type semiconductor layer 112; an active layer 114 on the first conductivity-type semiconductor layer 112; an AlInGaN-based nitride semiconductor layer 124 on the active layer 114; A second conductivity type semiconductor layer 116 may be included on the AlInGaN-based nitride semiconductor layer 124 .

Description

Light emitting device and lighting system {LIGHT EMITTING DEVICE, AND LIGHTING SYSTEM}

The embodiment relates to a light emitting device, a method of manufacturing a light emitting device, a light emitting device package, and a lighting system.

A light emitting device (Light Emitting Device: LED) is a pn junction diode with a characteristic in which electric energy is converted into light energy, which can be produced by combining elements of Groups 3-5 or 2-6 on the periodic table, and the composition ratio of compound semiconductors Various colors can be realized by adjusting.

When a forward voltage is applied, the electrons of the n-layer and the holes of the p-layer combine to emit energy corresponding to the bad gap energy of the conduction band and the valence band. , this energy is emitted in the form of heat or light, and when it is emitted in the form of light, it becomes a light emitting device.

For example, since nitride semiconductors have high thermal stability and wide bandgap energy, they are receiving great attention in the field of developing optical devices or high-power electronic devices. In particular, a blue light emitting device, a green light emitting device, an ultraviolet (UV) light emitting device, and a red light emitting device using a nitride semiconductor have been commercialized and widely used.

On the other hand, the light emitting device is formed by depositing an epi layer of a light emitting structure organically and chemically using a heterogeneous substrate as a growth substrate. , and such lattice defects degrade the crystal quality of the epitaxial thin film, thereby reducing the optical efficiency.

In addition, according to the prior art, there is a problem in that the defect of the epitaxial layer causes the absorption of photons by changing the energy level, thereby lowering the light output.

An embodiment is to provide a light emitting device capable of improving the light efficiency by improving the crystal quality of the epitaxial layer thin film, a method of manufacturing the light emitting device, a light emitting device package, and a lighting system.

In addition, the embodiment is intended to provide a light emitting device capable of improving light output by removing defects in the epitaxial layer, a method of manufacturing the light emitting device, a light emitting device package, and a lighting system.

The light emitting device according to the embodiment includes a first conductivity type semiconductor layer 112; an active layer 114 on the first conductivity-type semiconductor layer 112; an AlInGaN-based nitride semiconductor layer 124 on the active layer 114; A second conductivity type semiconductor layer 116 may be included on the AlInGaN-based nitride semiconductor layer 124 .

The second conductivity type semiconductor layer 116 may include a first conductivity type element injection layer 125 .

The lighting system according to the embodiment may include a light emitting unit including the light emitting device.

The embodiment may provide a light emitting device capable of improving light efficiency by improving the crystal quality of the epitaxial layer thin film, a method of manufacturing the light emitting device, a light emitting device package, and a lighting system.

In addition, the embodiment may provide a light emitting device capable of improving light output by removing defects in the epitaxial layer, a method of manufacturing a light emitting device, a light emitting device package, and a lighting system.

1 is a cross-sectional view of a light emitting device according to an embodiment;
2 is an elemental analysis diagram of a light emitting device according to an embodiment;
3 is luminous intensity data of a light emitting device according to an embodiment;
4 is a partially enlarged view of a light emitting device according to an embodiment;
5 to 8 are cross-sectional views of a method of manufacturing a light emitting device according to an embodiment.
9 is a cross-sectional view of a light emitting device package according to an embodiment.
10 is a perspective view of a lighting unit according to an embodiment;

In the description of an embodiment, each layer (film), region, pattern or structure is “on/over” or “under” the substrate, each layer (film), region, pad or pattern. In the case of being described as being formed on, “on/over” and “under” include both “directly” or “indirectly” formed through another layer. do. In addition, the criteria for the upper / upper or lower of each layer will be described with reference to the drawings.

(Example)

1 is a cross-sectional view of a light emitting device 100 according to an embodiment, and FIG. 1 is illustrated based on a horizontal light emitting device, but the embodiment is not limited thereto.

The light emitting device 100 according to the embodiment includes a first conductivity-type semiconductor layer 112 , an active layer 114 on the first conductivity-type semiconductor layer 112 , and an AlInGaN-based nitride semiconductor on the active layer 114 . A second conductivity type semiconductor layer 116 may be included on the layer 124 and the AlInGaN-based nitride semiconductor layer 124 .

The first conductivity type semiconductor layer 112 , the active layer 114 , and the second conductivity type semiconductor layer 116 may be referred to as a light emitting structure 110 . Unexplained reference numbers among the reference numbers shown in FIG. 1 will be described in the following manufacturing method.

2 is an elemental analysis diagram of the light emitting device according to the embodiment, and FIG. 4 is a partially enlarged view of the second conductivity type semiconductor layer 116 of the light emitting device according to the embodiment.

According to the prior art, there is a problem in that the lattice defects caused by the lattice difference between the growth substrate and the epitaxial layer deteriorate the crystal quality of the epitaxial layer or absorb photons to lower the light efficiency or the light output.

Accordingly, the embodiment intends to provide a light emitting device capable of improving light efficiency by improving the crystal quality of the epitaxial layer thin film and a light emitting device capable of improving light output by removing defects in the epi layer.

To this end, the embodiment may include the first conductivity type element injection layer 125 in the second conductivity type semiconductor layer 116 . For example, the second conductivity-type semiconductor layer 116 may be a p-type semiconductor layer, and the second conductivity-type semiconductor layer 116 may include an n-type injection layer 125 .

According to the embodiment, as shown in FIG. 2 or FIG. 4 , the second conductivity type semiconductor layer 116 by forming the n-type injection layer 125 on the second conductivity type semiconductor layer 116 while being spaced apart from the active layer 114 , For example, it is possible to reduce the gallium vacancy by filling the gallium vacancy remaining in the p-type GaN layer. It is possible to reduce the emission wavelength YL (Yellow Luminescence), so that the light efficiency can be increased, and the degree of absorption of photons due to defects is reduced, thereby improving the light output.

3 is luminous intensity data of a light emitting device according to an embodiment.

As shown in FIG. 3, compared to the luminous intensity (R) of the comparative example in which n-type ions are not implanted into the p-type semiconductor layer, about 130 mW, in the case of the light emitting device to which the embodiment is applied, the luminous intensity (E) increases to about 135 mW or more, so that the It had the effect of remarkably improving the light output.

Referring to FIG. 2 , in the embodiment, the n-type injection layer 125 may be doped with Si as an n-type doping element, and the doping concentration of Si may be about 8x10 ¹⁸ to about 2x10 ¹⁹ (atoms/cm ³ ). .

In an embodiment, the doping concentration of the p-type element in the second conductivity-type semiconductor layer 116 may be higher than the doping concentration of the n-type element in the n-type injection layer 125, and when it is lower than this, the second conductivity-type semiconductor layer It may be difficult for 116 to function as the injection layer of the hole. Accordingly, the doping concentration of Si in the n-type injection layer 125 may not exceed ^{2 ×10 19} (atoms/cm 3 ).

Also, in the embodiment, the doping concentration of the n-type element in the n-type injection layer 125 may be less than ^{8×10 18} (atoms/cm ^{3 ).} For example, as shown in FIG. 3 , when the doping concentration of the n-type conductive element in the n-type first injection layer 125a ^{is less than 8x10 18} (atoms/cm ³ ), the doping amount of the Si doping element is small, so that the degree of luminance improvement is low. It may not be large compared to the comparative example.

In an embodiment, the thickness of the first conductivity type element injection layer 125 may be thinner than the thickness of the AlInGaN-based nitride semiconductor layer 124 . When the thickness of the first conductivity type element injection layer 125 is greater than the thickness of the AlInGaN-based nitride semiconductor layer 124 , the first conductivity type element injection layer 125 may block injection of holes.

4 is a partially enlarged view of a light emitting device according to an embodiment.

In an embodiment, the first conductivity-type element injection layer 125 may include an n-type first injection layer 125a and an n-type second injection layer 125b, and the n-type first injection layer 125a The doping concentration of the n-type element in the n-type element may be higher than the doping concentration of the n-type element in the n-type second injection layer 125b.

In an embodiment, the doping concentration of Si of the n-type second injection layer 125b may also be lower than the doping concentration of Si of the n-type first injection layer 125a within the range of ^{8x10 18} to 2x10 ¹⁹ (atoms/cm ^{3 ).} have.

In an embodiment, the thickness of the first n-type injection layer 125a having a high doping concentration may be thinner than that of the second n-type injection layer 125b. Through this, by reducing the distribution of the n-type second injection layer 125b having a low doping concentration, the luminous intensity may be improved while minimizing side effects due to the doping of the heterogeneous material.

According to the embodiment, the number of the n-type first injection layers 125a having a high doping concentration may be less than that of the n-type second injection layers 125b, and through this, the n-type second injection layers 125b having a low doping concentration. ), it is possible to improve the luminosity while minimizing the side effects caused by doping with heterogeneous substances.

According to the embodiment, the n-type first injection layer 125a and the n-type second injection layer 125b of different concentrations are formed on the second conductivity-type semiconductor layer 116 , so that the gallium vacancy may be variously distributed. By filling (Ga Vacancy), it is possible to effectively remove defects and improve luminosity.

The embodiment can provide a light emitting device capable of improving the optical efficiency by improving the crystal quality of the epitaxial layer thin film, and improving the light output by removing the defects of the epitaxial layer.

Hereinafter, a method of manufacturing a light emitting device according to an embodiment will be described with reference to FIGS. 5 to 8 .

First, a substrate 105 is prepared as shown in FIG. 4 . The substrate 105 may be formed of a material having excellent thermal conductivity, and may be a conductive substrate or an insulating substrate. For example, the substrate 105 may include at least one _{of GaAs, sapphire (Al 2} O ₃ ), SiC, Si, GaN, ZnO, GaP, InP, Ge, and Ga ₂ 0 _{3 .} A concave-convex structure P may be formed on the substrate 105 , but the present invention is not limited thereto. The substrate 105 may be wet-cleaned to remove impurities on the surface.

A buffer layer 107 may be formed on the substrate 105 . The buffer layer 107 may relieve a lattice mismatch between the material of the light emitting structure 110 and the substrate 105 , and the material of the buffer layer 107 may be a group III-5 compound semiconductor, for example, GaN, InN, or AlN. , InGaN, AlGaN, InAlGaN, may be formed of at least one of AlInN. An undoped semiconductor layer (not shown) may be formed on the buffer layer 107 , but is not limited thereto.

Thereafter, the light emitting structure 110 including the first conductivity type semiconductor layer 112 , the active layer 114 and the second conductivity type semiconductor layer 116 is formed on the substrate 105 or the buffer layer 107 . can

The first conductivity type semiconductor layer 112 may be implemented with a semiconductor compound, for example, a compound semiconductor such as a group 3-5 or group 2-6, and may be doped with a first conductivity type dopant. When the first conductivity-type semiconductor layer 112 is an n-type semiconductor layer, the n-type dopant may include Si, Ge, Sn, Se, and Te, but is not limited thereto.

For example, the first conductivity type semiconductor layer 112 may be In _x Al _y Ga _1-xy N (0≤x≤1, 0≤y≤1, 0≤x+y≤1) or In _x Al _y It may include a semiconductor material having a composition formula of Ga _{1-xy P (0≤x≤1, 0≤y≤1, 0≤x+y≤1).}

For example, the first conductivity type semiconductor layer 112 may be formed of at least one of AlGaP, InGaP, AlInGaP, InP, GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, and GaP. can be

The first conductivity type semiconductor layer 112 may be formed using a method such as chemical vapor deposition (CVD), molecular beam epitaxy (MBE), sputtering or hydroxide vapor phase epitaxy (HVPE), but is not limited thereto. .

In an embodiment, a current diffusion layer (not shown) may be formed on the first conductivity-type semiconductor layer 112 . The current diffusion layer may be an undoped GaN layer, but is not limited thereto.

In addition, according to the embodiment, an electron injection layer (not shown), which is a first conductivity type gallium nitride layer, is formed on the current diffusion layer to increase electron injection efficiency.

Also, according to the embodiment, a strain control layer (not shown) may be formed on the electron injection layer. For example, the strain control layer may _{include a superlattice structure formed of In y} Al _x Ga _(1-xy) N(0≤x≤1, 0≤y≤1)/GaN. The strain control layer can effectively relieve stress caused by a lattice mismatch between the first conductivity-type semiconductor layer 112 and the active layer 114 .

Next, an active layer 114 may be formed on the first conductivity type semiconductor layer 112 or the strain control layer.

In the active layer 114, electrons injected through the first conductivity-type semiconductor layer 112 and holes injected through the second conductivity-type semiconductor layer 116 formed later meet each other to form an energy band unique to the active layer (light emitting layer) material. A layer that emits light with an energy determined by

The active layer 114 may be formed of at least one of a single quantum well structure, a multi quantum well (MQW) structure, a quantum-wire structure, or a quantum dot structure.

The active layer 114 may include a well layer/barrier layer structure. For example, the active layer 114 may include any one or more pairs of InGaN/GaN, InGaN/InGaN, GaN/AlGaN, InAlGaN/GaN, GaAs/AlGaAs, InGaAs/AlGaAs, GaInP/AlGaInP, GaP/AlGaP, and InGaP/AlGaP. It may be formed in a structure, but is not limited thereto. The well layer may be formed of a material having a band gap lower than a band gap of the barrier layer.

Next, an AlInGaN-based nitride semiconductor layer 124 may be formed on the active layer 114 . The AlInGaN-based nitride semiconductor layer 124 does not recombine in the active layer 114 , and effectively blocks electrons overflowing into the second conductivity-type semiconductor layer 116 , while increasing the hole injection efficiency into the active layer 114 . can be increased The AlInGaN-based nitride semiconductor layer 124 may have a bandgap energy greater than that of the active layer 114 .

The AlInGaN-based nitride semiconductor layer 124 may be formed of an Al _x In _y Ga _(1-xy) N (0≤x≤1, 0≤y≤1)-based semiconductor, but is not limited thereto. In addition, the AlInGaN-based nitride semiconductor layer 124 is Al _z Ga _(1-z) N/GaN (0≤z≤1) or Al _z In _y Ga _(1-zy) N/GaN (0≤z≤1, 0≤y≤1) may be formed as a superlattice, but is not limited thereto.

In addition, the AlInGaN-based nitride semiconductor layer 124 may be doped with a predetermined second conductivity type element. For example, Mg is implanted into the AlInGaN-based nitride semiconductor layer 124 to block electrons overflowing and to increase hole implantation efficiency.

Next, the second conductivity-type semiconductor layer 116 may be implemented with a compound semiconductor such as Group III-5, Group II-6, or the like, and may be doped with a second conductivity-type dopant.

For example, the second conductivity type semiconductor layer 116 may be In _x Al _y Ga _1-xy N (0≤x≤1, 0≤y≤1, 0≤x+y≤1) or In _x Al _y It may be formed of a semiconductor material having a composition formula of Ga _{1-xy P (0≤x≤1, 0≤y≤1, 0≤x+y≤1).} When the second conductivity-type semiconductor layer 116 is a p-type semiconductor layer, Mg, Zn, Ca, Sr, Ba, or the like may be doped as a p-type dopant.

In an embodiment, the first conductivity-type semiconductor layer 112 may be an n-type semiconductor layer, and the second conductivity-type semiconductor layer 116 may be implemented as a p-type semiconductor layer, but is not limited thereto. In addition, a semiconductor having a polarity opposite to that of the second conductivity type, for example, an n-type semiconductor layer (not shown) may be formed on the second conductivity type semiconductor layer 116 . Accordingly, the light emitting structure 110 may be implemented as any one of an n-p junction structure, a p-n junction structure, an n-p-n junction structure, and a p-n-p junction structure.

Hereinafter, the features of the embodiment will be described in more detail with reference to FIG. 2 or FIG. 4 .

In the embodiment, as shown in FIG. 2 , the first conductivity type element injection layer 125 may be included in the second conductivity type semiconductor layer 116 , for example, SiH ₄ flow into the second conductivity type semiconductor layer 116 . As the (flow) process proceeds to form the n-type injection layer 125 , the gallium vacancy (Ga Vacancy) remaining in the p-type GaN layer can be filled _{to reduce the gallium vacancy (V Ga} ), thereby reducing lattice defects. It is possible to reduce YL (yellow luminescence), which is an emission wavelength not in the designed wavelength band, as the defect is reduced.

In the embodiment, the doping concentration of Si of the n-type injection layer 125 formed in the second conductivity-type semiconductor layer 116 may be 8x10 ¹⁸ to 2x10 ¹⁹ (atoms/cm ³ ).

In an embodiment, the doping concentration of the p-type element in the second conductivity-type semiconductor layer 116 may be higher than the doping concentration of the n-type element of the n-type injection layer 125 , and when it is lower than this, the second conductivity-type semiconductor layer It may be difficult for 116 to function as the injection layer of the hole. Accordingly, the doping concentration of Si of the n-type injection layer 125 may not exceed ^{2 ×10 19} (atoms/cm 3 ).

Also, in the embodiment, the doping concentration of the n-type element in the n-type injection layer 125 may be less than ^{8×10 18} (atoms/cm ^{3 ).} For example, when the doping concentration of the n-type element in the n-type injection layer 125 is ^{less than 8x10 18} (atoms/cm ³ ), the doping amount of the Si doping element is small, so that the degree of luminance improvement may not be large compared to the comparative example.

According to an embodiment, the first conductivity-type element injection layer 125 may include an n-type first injection layer 125a and an n-type second injection layer 125b, and the n-type first injection layer ( The doping concentration of the n-type element in 125a may be higher than that of the n-type element in the n-type second injection layer 125b.

In an embodiment, the doping concentration of Si of the n-type second injection layer 125b may be lower than the doping concentration of Si of the n-type first injection layer 125a within the range ^{of 8x10 18} to 2x10 ¹⁹ (atoms/cm ^{3 ).} have.

According to the embodiment, by forming the n-type injection layers 125 of different concentrations on the second conductivity type semiconductor layer 116 , Ga Vacancy, which may be distributed in various ways, is filled and defects are filled. It can be effectively removed to improve the luminosity.

Next, as shown in FIG. 6 , a configuration disposed on the upper side of the first conductivity-type semiconductor layer 112 may be partially removed to partially expose it. For example, a portion of the second conductivity type semiconductor layer 116 including the first conductivity type element injection layer 125 , the AlInGaN-based nitride semiconductor layer 124 , and the active layer 114 is formed by wet etching or dry etching. A portion of the upper surface of the first conductivity-type semiconductor layer 112 may be exposed by being removed, and a portion of the first conductivity-type semiconductor layer 112 may also be removed, but is not limited thereto.

Next, as shown in FIG. 7 , the current blocking layer 130 may be formed at a position where the second electrode 152 is to be formed. The current blocking layer 130 may include a non-conductive region, a first conductive ion implantation layer, a first conductive diffusion layer, an insulating material, an amorphous region, and the like.

Next, the light-transmitting electrode layer 140 may be formed on the second conductivity-type semiconductor layer 116 on which the current blocking layer 130 is formed. The light-transmitting electrode layer 140 may include an ohmic layer, and may be formed by stacking a single metal, a metal alloy, or a metal oxide in multiple layers to efficiently inject holes.

For example, the light-transmitting electrode layer 140 may be formed of an excellent material that is in electrical contact with a semiconductor. For example, the light-transmitting electrode layer 140 may include indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), or IGTO. (indium gallium tin oxide), AZO (aluminum zinc oxide), ATO (antimony tin oxide), GZO (gallium zinc oxide), IZON (IZO Nitride), AGZO (Al-Ga ZnO), IGZO (In-Ga ZnO), ZnO, IrOx, RuOx, NiO, RuOx/ITO, Ni/IrOx/Au, and Ni/IrOx/Au/ITO, Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt , Au, may be formed to include at least one of Hf, but is not limited thereto.

Thereafter, the passivation layer 160 may be formed as an insulating layer or the like on the side surface of the light emitting structure 110 and a part of the light-transmitting electrode layer 140 . The passivation layer 160 may expose a region where the first electrode 151 and the second electrode 152 are to be formed.

Next, as shown in FIG. 8 , a second electrode 152 may be formed on the light-transmitting electrode layer 140 to overlap the current blocking layer 130 , and on the exposed first conductivity-type semiconductor layer 112 . Since the first electrode 151 is formed, the light emitting device according to the embodiment may be manufactured.

The first electrode 151 or the second electrode 152 may include titanium (Ti), chromium (Cr), nickel (Ni), aluminum (Al), platinum (Pt), gold (Au), tungsten (W), It may be formed of at least one of molybdenum (Mo), but is not limited thereto.

A plurality of light emitting devices according to the embodiment may be arrayed on a substrate in the form of a package, and optical members such as a light guide plate, a prism sheet, a diffusion sheet, a fluorescent sheet, etc. may be disposed on a path of light emitted from the light emitting device package.

8 is a cross-sectional view of the light emitting device package 200 in which the light emitting device according to the embodiment is installed.

The light emitting device package 200 according to the embodiment includes a package body part 205 , a third electrode layer 213 and a fourth electrode layer 214 installed on the package body part 205 , and the package body part 205 . A molding member 230 provided in the light emitting device 100 and electrically connected to the third electrode layer 213 and the fourth electrode layer 214 and a phosphor 232 to surround the light emitting device 100 . may include.

The third electrode layer 213 and the fourth electrode layer 214 are electrically isolated from each other, and serve to provide power to the light emitting device 100 . In addition, the third electrode layer 213 and the fourth electrode layer 214 may serve to increase light efficiency by reflecting the light generated from the light emitting device 100 , and It can also serve to dissipate heat to the outside.

The light emitting device 100 may be electrically connected to the third electrode layer 213 and/or the fourth electrode layer 214 by any one of a wire method, a flip chip method, and a die bonding method.

The light emitting device according to the embodiment may be applied to a backlight unit, a lighting unit, a display device, an indicator device, a lamp, a street lamp, a vehicle lighting device, a vehicle display device, a smart watch, and the like, but is not limited thereto.

10 is an exploded perspective view of a lighting system including a light emitting device and a light emitting device package according to an embodiment.

The lighting device according to the embodiment may include a cover 2100 , a light source module 2200 , a heat sink 2400 , a power supply unit 2600 , an inner case 2700 , and a socket 2800 . In addition, the lighting device according to the embodiment may further include any one or more of the member 2300 and the holder 2500 . The light source module 2200 may include a light emitting device or a light emitting device package according to an embodiment.

The light source module 2200 may include a light source unit 2210 , a connection plate 2230 , and a connector 2250 . The member 2300 is disposed on the upper surface of the heat sink 2400 and includes a plurality of light source units 2210 and guide grooves 2310 into which the connector 2250 is inserted.

The holder 2500 blocks the receiving groove 2719 of the insulating part 2710 of the inner case 2700 . Accordingly, the power supply unit 2600 accommodated in the insulating unit 2710 of the inner case 2700 is sealed. The holder 2500 has a guide protrusion 2510 .

The power supply unit 2600 may include a protrusion part 2610 , a guide part 2630 , a base 2650 , and an extension part 2670 . The inner case 2700 may include a molding unit together with the power supply unit 2600 therein. The molding part is a part where the molding liquid is hardened, and allows the power supply unit 2600 to be fixed inside the inner case 2700 .

Features, structures, effects, etc. described in the above embodiments are included in at least one embodiment, and are not necessarily limited to only one embodiment. Furthermore, features, structures, effects, etc. illustrated in each embodiment can be combined or modified for other embodiments by those of ordinary skill in the art to which the embodiments belong. Accordingly, the contents related to such combinations and modifications should be interpreted as being included in the scope of the embodiments.

In the above, the embodiment has been mainly described, but this is only an example and not limiting the embodiment, and those of ordinary skill in the art to which the embodiment pertains are provided with several examples not illustrated above in the range that does not depart from the essential characteristics of the embodiment. It can be seen that variations and applications of branches are possible. For example, each component specifically shown in the embodiment can be implemented by modification. And differences related to such modifications and applications should be construed as being included in the scope of the embodiments set forth in the appended claims.

a first conductivity type semiconductor layer 112 , an active layer 114 ;
AlInGaN-based nitride semiconductor layer 124, second conductivity type semiconductor layer 116;
The first conductivity-type element injection layer 125 , the n-type first injection layer 125a , and the n-type second injection layer 125b

Claims (8)

a first conductivity type semiconductor layer doped with a first conductivity type element;
an active layer on the first conductivity type semiconductor layer;
an AlInGaN-based nitride semiconductor layer on the active layer; and
a second conductivity type semiconductor layer doped with a second conductivity type element on the AlInGaN-based nitride semiconductor layer;
The second conductivity type semiconductor layer includes a first conductivity type element injection layer disposed in the second conductivity type semiconductor layer and including the first conductivity type element,
The first conductivity type element includes an n-type doping element and the second conductivity type element includes a p-type doping element,
The thickness of the first conductive element injection layer is thinner than the thickness of the AlInGaN-based nitride semiconductor layer,
The first conductive element injection layer includes a first injection layer and a second injection layer,
The doping concentration of the first conductive type element doped in the first injection layer is higher than the doping concentration of the first conductive type element doped in the second injection layer,
The thickness of the first injection layer is thinner than the thickness of the second injection layer,
The number of the first injection layer is less than the number of the second injection layer,
The first injection layer and the second injection layer are light emitting devices disposed in a central region of the second conductivity type semiconductor layer spaced apart from the upper and lower surfaces of the second conductivity type semiconductor layer. delete delete delete delete delete delete delete

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