KR101297788B1 - Light emitting device - Google Patents

Abstract

PURPOSE: A light emitting device is provided to reduce light efficiency droop, thereby generating high power. CONSTITUTION: An n-type semiconductor layer is formed on a substrate. An electron barrier layer (103) is formed on the n-type semiconductor layer. An active layer (104) is formed on the electron barrier layer. A p-type semiconductor layer (105) is formed on the active layer. An undoped semiconductor layer is formed between the n-type semiconductor layer and the electron barrier layer.

Description

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting device, and more particularly, to a light emitting device capable of realizing a high output light emitting device by reducing the supply imbalance of holes and electrons to the active layer, thereby increasing the light emission efficiency and reducing the efficiency droop. It is about.

The light emitting device converts electrical energy into light energy and emits light to the outside. An example of such a light emitting device is a light emitting diode (LED) capable of generating light of various colors by recombination of holes and electrons in the active layers of junctions of p-type and n-type semiconductors when voltage is applied.

Light emitting diodes are attracting attention as next generation light emitting devices due to their environmentally friendly, high energy efficiency and high reliability.

Recently, as the technology of light emitting diodes develops and the brightness increases, it is required that a larger amount of current be supplied to the light emitting diodes.

However, an efficiency droop occurs when a larger amount of current is supplied to the light emitting diode. An efficiency droop is a phenomenon in which the external quantum efficiency decreases as the amount of current supplied increases, which is the biggest obstacle to realizing a high output light emitting diode for lighting, which is the main purpose of applying a light emitting diode (see FIG. 1). .

It is known that such a phenomenon in light efficiency is caused by a combination of various causes, and the mechanism is not precisely defined. One of these causes is the lack of hole supply due to the difference in speed between electrons and one hole. In other words, the same number of electrons and holes are required, but due to the large mass difference between electrons and holes, the mobility of electrons and holes remains largely different, resulting in a difference in supply of electrons and holes.

This difference in supply of electrons and holes leads to a lack of holes (oversupply of electrons), especially in high power light emitting diodes, resulting in current overflow or current leakage, in which electrons that failed to recombine due to insufficient holes overflow the active layer. There is a problem that (leakage) occurs.
In order to solve this problem, there have been attempts as in Korean Patent Laid-Open Publication No. 10-2012-0011198 published on February 7, 2012.

SUMMARY OF THE INVENTION An object of the present invention is to provide a light emitting device capable of realizing a high output light emitting device by reducing the supply imbalance of holes and electrons to the active layer to increase the luminous efficiency and reduce the efficiency droop.

A light emitting device according to an embodiment of the present invention for achieving the above object is a substrate; An n-type semiconductor layer formed on the substrate; An electron blocking layer formed on the n-type semiconductor layer; An active layer formed on the electron blocking layer; It characterized in that it comprises a p-type semiconductor layer formed on the active layer.

The electron blocking layer may have a higher bandgap energy than the n-type semiconductor layer.

The electron blocking layer may be formed of Al _X Ga _(1-X) N (0 <X≤1).

The electron blocking layer may have a thickness of 10nm to 50nm.

The active layer may be formed by alternately arranging at least one quantum well layer and a quantum barrier layer.

In addition, the light emitting device according to the embodiment of the present invention comprises a p-type electrode formed on the p-type semiconductor layer; And an n-type electrode formed on one side of the n-type semiconductor layer opposite to the surface in contact with the substrate.

In addition, the light emitting device according to the embodiment of the present invention may further include an undoped semiconductor layer formed between the electron blocking layer and the active layer.

In addition, the light emitting device according to the embodiment of the present invention may further include an undoped semiconductor layer formed between the n-type semiconductor layer and the electron blocking layer.

The undoped semiconductor layer may have a lower bandgap energy than the electron blocking layer.

The undoped semiconductor layer may have a thickness of 10 nm to 50 nm.

In addition, the light emitting device according to the embodiment of the present invention may further include an electron overflow prevention layer formed between the active layer and the p-type semiconductor layer.

The bandgap energy of the overflow prevention layer may be greater than the bandgap energy of the n-type semiconductor layer and less than the bandgap energy of the electron blocking layer.

In addition, a light emitting device according to an embodiment of the present invention for achieving the above object is a substrate; A p-type semiconductor layer formed on the substrate; An active layer formed on the p-type semiconductor layer; An electron blocking layer formed on the active layer; It characterized in that it comprises an n-type semiconductor layer formed on the electron blocking layer.

The electron blocking layer may have a higher bandgap energy than the n-type semiconductor layer.

The electron blocking layer may be formed of Al _X Ga _(1-X) N (0 <X≤1).

The electron blocking layer may have a thickness of 10nm to 50nm.

The active layer may be formed by alternately arranging at least one quantum well layer and a quantum barrier layer.

In addition, the light emitting device according to the embodiment of the present invention may include an n-type electrode formed on the n-type semiconductor layer.

In addition, the light emitting device according to the embodiment of the present invention may further include a p-type electrode interposed between the p-type semiconductor layer and the substrate.

In addition, the light emitting device according to the embodiment of the present invention may further include an electron overflow prevention layer formed between the active layer and the p-type semiconductor layer.

The bandgap energy of the overflow prevention layer may be greater than the bandgap energy of the n-type semiconductor layer and less than the bandgap energy of the electron blocking layer.

The light emitting device according to the embodiment of the present invention has an electron blocking layer formed between the n-type semiconductor layer and the active layer, thereby improving the hole injection efficiency without disturbing the supply of holes to the active layer and having a large mass smaller than the hole. It may disturb the supply of electrons having mobility.

Accordingly, the light emitting device according to the embodiment of the present invention can increase the light emitting efficiency by reducing the supply imbalance of electrons and holes to the active layer, and can implement the high output light emitting device by reducing the efficiency droop. It can be done.

1 is a graph for explaining a light efficiency deterioration phenomenon occurring in a high output light emitting diode.
2 is a cross-sectional view of a light emitting device according to an embodiment of the present invention.
3 is an energy band diagram of the light emitting device illustrated in FIG. 2.
FIG. 4 is an energy band diagram showing movement of electrons and holes when the light emitting device of FIG. 2 has a low current density.
5 is a cross-sectional view of a light emitting device according to another embodiment of the present invention.
FIG. 6 is an energy band diagram of the light emitting device illustrated in FIG. 5.
7 is a cross-sectional view of a light emitting device according to still another embodiment of the present invention.
FIG. 8 is an energy band diagram of the light emitting device illustrated in FIG. 7.
9 is a cross-sectional view of a light emitting device according to another embodiment of the present invention.
FIG. 10 is an energy band diagram of the light emitting device illustrated in FIG. 9.
11 is a cross-sectional view of a light emitting device according to still another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

2 is a cross-sectional view of a light emitting device according to an embodiment of the present invention, FIG. 3 is an energy band diagram of the light emitting device shown in FIG. 2, and FIG. 4 is a view showing electrons when the light emitting device of FIG. 2 has a low current density. An energy band diagram showing the movement of holes.

Referring to FIG. 2, the light emitting device 100 according to the exemplary embodiment may include a substrate 101, an n-type semiconductor layer 102, an electron blocking layer 103, an active layer 104, and a p-type semiconductor layer ( 105, p-type electrode 106 and n-type electrode 107. The light emitting device 100 may implement a horizontal light emitting diode.

The substrate 101 may be selected from a group consisting of sapphire substrate (Al ₂ O ₃ ), GaN, SiC, ZnO, Si, GaP, InP, Ga ₂ O ₃ , a conductive substrate and GaAs.

Semiconductor material having a composition formula of the n-type semiconductor layer 102 is _{In x Al y Ga 1 -x- y} N (0≤x≤1, 0 ≤y≤1, 0≤x + y≤1), For For example, it may be selected from InAlGaN, GaN, AlGaN, AlInN, InGaN, AlN, InN, and the like, and an n-type dopant such as Si, Ge, Sn, or the like may be doped. Here, the doping concentration of the n-type dopant may be 1 ~ 5 × 10 ¹⁸ cm ³ .

The electron blocking layer EBL 103 is formed on the n-type semiconductor layer 102 and has a higher bandgap energy than the n-type semiconductor layer 102 as shown in FIG. 3. The electron blocking layer 103 prevents the supply of electrons provided from the n-type semiconductor layer 102 to the active layer 104 without disturbing the supply of holes provided from the p-type semiconductor layer 105 to the active layer 104. Disturb. The electron blocking layer 103 may reduce the supply imbalance between the electrons and the holes to the active layer 104 by improving the hole injection efficiency while preventing the supply of electrons having a greater mobility than the holes. Accordingly, the electron blocking layer 103 may increase the luminous efficiency by recombination of electrons and holes, and current overflows in which electrons that are not recrystallized due to lack of holes in the active layer overflow out of the active layer. Alternatively, current leakage can be prevented from occurring.

On the other hand, referring to Figure 4 when the light emitting device 100 according to an embodiment of the present invention has a low current density, holes are first filled in the active layer 104 so that the overflow of the hole in the active layer 104 does not occur. However, when the light emitting device 100 according to the exemplary embodiment of the present invention has an increased current density for high power, electrons are supplied to the active layer 104 beyond the electron blocking layer 103 to recombine with the holes. Accordingly, the electron blocking layer 103 may be applied to implement a light emitting device for high power illumination, and may reduce the light efficiency resistance phenomenon.

The electron blocking layer 103 may be formed of Al _X Ga _(1-X) N (0 <X≤1), and may have a thickness of about 10 nm to about 50 nm so as not to significantly disturb the supply of electrons.

The active layer 104 is formed on the electron blocking layer 103, for example, In _x Al _y Ga _{1 -xy} N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ x + y ≦ 1). A single quantum well structure having a quantum well layer, and a multi quantum well structure in which at least one quantum well layer and a quantum barrier layer are alternately arranged (MQW: Multi Quantum Well) The quantum dot structure or the quantum wire structure may be formed of any one. 3 and 4, it is shown that the active layer 104 is formed of, for example, a multi quantum well structure (MQW). Here, the quantum barrier layer of the multi quantum well structure (MQW) constituting the active layer 104 may have a lower band gap energy than the electron blocking layer 103. This is because if the quantum barrier layer of the multi-quantum well structure (MQW) constituting the active layer 104 has a higher bandgap than the electron blocking layer 103, electrons cannot be smoothly transferred from the electron blocking layer 103 to the quantum barrier layer. Because.

The active layer 104 as described above may generate light by energy generated during the recombination of electrons and holes of the n-type conductive semiconductor layer 101 and the p-conductive semiconductor layer 105.

The p-type semiconductor layer 105 is formed on the active layer _{(104), In x Al y} Ga 1 -x- y N (0≤x≤1, 0 ≤y≤1, 0≤x + y≤1) A semiconductor material having a compositional formula may be selected from, for example, InAlGaN, GaN, AlGaN, AlInN, InGaN, AlN, InN, and the like, and p-type dopants such as Mg, Zn, Ca, Sr, and Ba may be doped. Here, the doping concentration of the p-type dopant may be 1 ~ 5 × 10 ¹⁷ cm ³ .

The p-type electrode 106 is formed on the p-type semiconductor layer 105, and is formed of a conductive metal to serve as an electrode.

The n-type electrode 107 is formed on one side of the n-type semiconductor layer 102 opposite to the surface in contact with the substrate 101, and is formed of a conductive metal to serve as an electrode.

As described above, the light emitting device 100 according to the exemplary embodiment of the present invention includes the electron blocking layer 103 formed between the n-type semiconductor layer 102 and the active layer 104, thereby forming holes in the active layer 104. It is possible to hinder the supply of electrons having a large mobility by having a mass smaller than the hole while improving the hole injection efficiency without disturbing the supply of.

Accordingly, the light emitting device 100 according to the embodiment of the present invention can increase the luminous efficiency by reducing the supply imbalance of electrons and holes to the active layer 104, and reduces the efficiency droop. It can enable the implementation of a high output light emitting device, for example a high output horizontal structure light emitting diode.

Next, a light emitting device 200 according to another embodiment of the present invention will be described.

5 is a cross-sectional view of a light emitting device according to another embodiment of the present invention, and FIG. 6 is an energy band diagram of the light emitting device shown in FIG.

The light emitting device 200 according to another embodiment of the present invention is different from the light emitting device 100 according to an embodiment of the present invention, except that an undoped semiconductor layer 208 is further formed. Has a configuration. Accordingly, in the light emitting device 200 according to another embodiment of the present invention, only the undoped semiconductor layer 208 will be described.

Referring to FIG. 5, a light emitting device 200 according to another embodiment of the present invention may include a substrate 101, an n-type semiconductor layer 102, an electron blocking layer 103, an undoped semiconductor layer 208, and an active layer ( 104, a p-type semiconductor layer 105, a p-type electrode 106 and an n-type electrode 107. The light emitting device 200 may implement a horizontal structure light emitting diode.

The undoped semiconductor layer 208 may be formed between the electron blocking layer 103 and the active layer 104, and may be formed of, for example, undoped GaN (u-GaN). The undoped semiconductor layer 208 has a lower bandgap energy than the electron blocking layer 103 as shown in FIG. 6. The undoped semiconductor layer 208 further interferes with the supply of electrons provided from the n-type semiconductor layer 102 to the active layer 104. The undoped semiconductor layer 208, together with the electron blocking layer 103, may block the supply of electrons to reduce the supply imbalance of electrons and holes to the active layer 104, thereby preventing electron overflow or current leakage. have. In addition, the undoped semiconductor layer 208 may improve the quality of the layer by reducing the difference in the lattice constant with the active layer 104. Here, the undoped semiconductor layer 208 may have a thickness of 10nm to 50nm so as not to significantly interfere with the supply of electrons.

As described above, the light emitting device 200 according to another embodiment of the present invention includes an undoped semiconductor layer 208 formed between the electron blocking layer 103 and the active layer 104, thereby improving the quality of the layer. In addition, the hole blocking efficiency may be improved together with the electron blocking layer 103 without hindering the supply of holes to the active layer 104, thereby preventing the supply of electrons having a large mobility by having a mass smaller than the holes.

Therefore, the light emitting device 200 according to another embodiment of the present invention can more effectively reduce the supply imbalance of electrons and holes to the active layer 104 to increase the luminous efficiency, and reduces the light efficiency drop phenomenon. It can be reduced to enable the implementation of high power light emitting devices, for example high power horizontal structure light emitting diodes.

Next, a light emitting device 300 according to another embodiment of the present invention will be described.

7 is a cross-sectional view of a light emitting device according to another embodiment of the present invention, and FIG. 8 is an energy band diagram of the light emitting device shown in FIG.

The light emitting device 300 according to another embodiment of the present invention differs only in that an undoped semiconductor layer 308 is further formed compared to the light emitting device 100 according to an embodiment of the present invention. Only have the same configuration. Accordingly, in the light emitting device 300 according to still another embodiment of the present invention, only the undoped semiconductor layer 308 will be described.

Referring to FIG. 7, the light emitting device 300 according to another embodiment of the present invention may include a substrate 101, an n-type semiconductor layer 102, an undoped semiconductor layer 308, an electron blocking layer 103, and an active layer. 104, a p-type semiconductor layer 105, a p-type electrode 106 and an n-type electrode 107. The light emitting device 300 may implement a horizontal structure light emitting diode.

The undoped semiconductor layer 308 may be formed between the n-type semiconductor layer 102 and the electron blocking layer 103, and may be formed of, for example, an undoped GaN layer. As shown in FIG. 8, the undoped semiconductor layer 308 has a lower bandgap energy than the electron blocking layer 103. The undoped semiconductor layer 308 additionally interferes with the supply of electrons provided from the n-type semiconductor layer 102 to the active layer 104. The undoped semiconductor layer 38, together with the electron blocking layer 103, may block the supply of electrons to reduce the supply imbalance of electrons and holes to the active layer 104, thereby preventing electron overflow or current leakage. have. In addition, the undoped semiconductor layer 308 may improve the quality of the layer by reducing the difference in the lattice constant with the electron blocking layer 103. Here, the undoped semiconductor layer 308 may have a thickness of 10nm to 50nm so as not to significantly interfere with the supply of electrons.

As described above, the light emitting device 300 according to another embodiment of the present invention includes an undoped semiconductor layer 308 formed between the n-type semiconductor layer 102 and the electron blocking layer 103, thereby providing a quality of the layer. Can improve the hole injection efficiency without disturbing the supply of holes to the active layer 104 together with the electron blocking layer 103 and have a mass less than the holes to interfere with the supply of electrons having large mobility. Can be.

Therefore, the light emitting device 300 according to another embodiment of the present invention can more effectively reduce the supply imbalance of electrons and holes to the active layer 104 to increase the luminous efficiency, and the light efficiency drop phenomenon (Efficiency droop) It can be possible to implement a high output light emitting device, for example, a high output horizontal structure light emitting diode.

Next, a light emitting device 400 according to another embodiment of the present invention will be described.

9 is a cross-sectional view of a light emitting device according to still another embodiment of the present invention, and FIG. 10 is an energy band diagram of the light emitting device shown in FIG. 9.

In the light emitting device 400 according to another embodiment of the present invention, an electron overflow prevention layer (EOPL) 409 is further formed as compared to the light emitting device 100 according to an embodiment of the present invention. Only points are different and have the same configuration. Accordingly, in the light emitting device 400 according to another exemplary embodiment, only the electron overflow prevention layer 409 will be described.

9, the light emitting device 400 according to another embodiment of the present invention may include a substrate 101, an n-type semiconductor layer 102, an electron blocking layer 103, an active layer 104, and an electron overflow prevention layer. 409, a p-type semiconductor layer 105, a p-type electrode 106, and an n-type electrode 107. The light emitting device 400 may implement a horizontal structure light emitting diode.

The electron overflow prevention layer 409 is formed between the active layer 104 and the p-type semiconductor layer 105. The electron overflow prevention layer 409 is formed of the same material as the electron blocking layer 103. The electron overflow prevention layer 409 effectively prevents electrons supplied from the n-type semiconductor layer 102 to the active layer 104 from overflowing to the p-type semiconductor layer 105 without recombination in the active layer 104. Accordingly, the electron overflow prevention layer 409 may reduce the consumption of electrons in the active layer 104 due to the overflow of electrons, thereby improving luminous efficiency of the light emitting device. Here, the electron overflow prevention layer 409 has a bandgap energy greater than the bandgap energy of the n-type semiconductor layer 102 and less than the bandgap energy of the electron blocking layer 103.

As described above, the light emitting device 400 according to another exemplary embodiment of the present invention includes an electron overflow prevention layer 409 formed between the active layer 104 and the p-type semiconductor layer 105, thereby preventing the electron blocking layer 103. ) And improve the hole injection efficiency without disturbing the supply of holes to the active layer 104 as much as possible to have a mass less than the hole to interfere with the supply of electrons having a large mobility, and to further increase the electron overflow Can be effectively prevented.

Therefore, the light emitting device 400 according to another embodiment of the present invention can increase the luminous efficiency by more effectively reducing the supply imbalance of electrons and holes to the active layer 104, the light efficiency drop phenomenon (Efficiency droop) It can be possible to implement a high output light emitting device, for example, a high output horizontal structure light emitting diode.

Next, a light emitting device 500 according to another embodiment of the present invention will be described.

11 is a cross-sectional view of a light emitting device according to still another embodiment of the present invention.

The light emitting device 500 according to another exemplary embodiment of the present invention may include a substrate 501, a p-type electrode 502, a p-type semiconductor layer 503, an active layer 504, an electron difference layer 505, and an n-type semiconductor. Layer 506 and n-type electrode 507. The light emitting device 500 may implement a vertical structure light emitting diode.

The substrate 501 serves as a support of the light emitting device 500. The substrate 501 is formed of an insulating material in the p-type semiconductor layer 503, or a conductive material such as Cu, Au, Ni, Mo, Cu-W, and a carrier wafer (for example, Si, Ge GaAs, ZnO, Sic, etc.).

The p-type electrode 502 is formed on the substrate 501 and may be formed of a conductive material to apply a voltage to the p-type semiconductor layer 503 and the n-type semiconductor layer 506 together with the n-type electrode 507. have. On the other hand, the p-type electrode 502 may be omitted if the substrate 501 is formed of a conductive material to serve as an electrode.

The p-type semiconductor layer 503 is formed on the substrate 501, more specifically, on the p-type electrode 502, formed of the same material as the p-type semiconductor layer 105 of FIG. Therefore, duplicate descriptions will be omitted.

Since the active layer 504 is formed on the p-type semiconductor layer 503 and is formed of the same material as the active layer 104 of FIG. 2 and plays the same role, redundant descriptions thereof will be omitted.

The electron blocking layer 505 is formed on the active layer 504, and is formed of the same material as the electron blocking layer 103 of FIG.

The n-type semiconductor layer 506 is formed on the electron blocking layer 505, and is formed of the same material as the n-type semiconductor layer 102 of FIG.

Since the n-type electrode 507 is formed on the n-type semiconductor layer 506, and formed of the same material as the n-type electrode 107 of FIG. 2 and play the same role, redundant description thereof will be omitted.

As described above, the light emitting device 500 according to another exemplary embodiment of the present invention includes the electron blocking layer 505 formed between the n-type semiconductor layer 506 and the active layer 504, thereby providing the active layer 504. It is possible to hinder the supply of electrons having a large mobility by having a mass smaller than the hole while improving the hole injection efficiency without disturbing the supply of holes.

Accordingly, the light emitting device 500 according to another embodiment of the present invention can increase the luminous efficiency by reducing the supply imbalance of electrons and holes to the active layer 504, and reduce the efficiency droop. It is possible to implement a high output light emitting device, for example, a high output vertical structure light emitting diode.

Although not shown, the light emitting device 500 of FIG. 11 may be formed by forming the overflow prevention layer 409 of FIG. 9 between the active layer 504 and the p-type semiconductor layer 503.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation and that those skilled in the art will understand that various modifications and equivalent arrangements may be made therein It will be possible.

100, 200, 300, 400, 500: light emitting element 101, 501: substrate
102, 507: n-type electrode 103, 505: electron blocking layer
104, 504: active layer 105, 503: p-type semiconductor layer
106, 502: p-type electrode 107, 507: n-type electrode
409: electronic overflow protection layer

Claims (21)

Board;
An n-type semiconductor layer formed on the substrate;
An electron blocking layer, which is a semiconductor layer formed on the n-type semiconductor layer;
An active layer formed on the electron blocking layer; And
A light emitting device comprising a p-type semiconductor layer formed on the active layer,
And a undoped semiconductor layer formed between the n-type semiconductor layer and the electron blocking layer. The method of claim 1,
The electron blocking layer has a higher band gap energy than the n-type semiconductor layer. The method of claim 1,
The electron blocking layer is formed of Al _X Ga _(1-X) N (0 < _X ≤ 1). The method of claim 1,
The electron blocking layer has a thickness of 10nm ~ 50nm. The method of claim 1,
The active layer is a light emitting device, characterized in that formed by alternating at least one quantum well layer and the quantum barrier layer. The method of claim 1,
A p-type electrode formed on the p-type semiconductor layer; And
The n-type semiconductor layer further comprises an n-type electrode formed on one side of the opposite surface of the n-type semiconductor layer in contact with the substrate. The method of claim 1,
And a undoped semiconductor layer formed between the electron blocking layer and the active layer. delete The method of claim 7, wherein
The undoped semiconductor layer has a lower band gap energy than the electron blocking layer. The method of claim 7, wherein
The undoped semiconductor layer has a thickness of 10nm to 50nm. 3. The method of claim 2,
And an electron overflow prevention layer formed between the active layer and the p-type semiconductor layer. Board;
An n-type semiconductor layer formed on the substrate;
An electron blocking layer, which is a semiconductor layer formed on the n-type semiconductor layer;
An active layer formed on the electron blocking layer; And
A light emitting device comprising a p-type semiconductor layer formed on the active layer,
Further comprising an electron overflow prevention layer formed between the active layer and the p-type semiconductor layer,
The band gap energy of the overflow prevention layer is greater than the band gap energy of the n-type semiconductor layer and less than the band gap energy of the electron blocking layer. Board;
A p-type semiconductor layer formed on the substrate;
An active layer formed on the p-type semiconductor layer;
An electron blocking layer, which is a semiconductor layer formed on the active layer; And
A light emitting device comprising an n-type semiconductor layer formed on the electron blocking layer,
And a undoped semiconductor layer formed between the n-type semiconductor layer and the electron blocking layer. The method of claim 13,
The electron blocking layer has a higher band gap energy than the n-type semiconductor layer. The method of claim 13,
The electron blocking layer is formed of Al _X Ga _(1-X) N (0 < _X ≤ 1). The method of claim 13,
The electron blocking layer has a thickness of 10nm ~ 50nm. The method of claim 13,
The active layer is a light emitting device, characterized in that formed by alternating at least one quantum well layer and the quantum barrier layer. The method of claim 13,
And an n-type electrode formed on the n-type semiconductor layer. The method of claim 18,
Light emitting device further comprises a p-type electrode interposed between the p-type semiconductor layer and the substrate. The method of claim 13,
And an electron overflow prevention layer formed between the active layer and the p-type semiconductor layer. Board;
A p-type semiconductor layer formed on the substrate;
An active layer formed on the p-type semiconductor layer;
An electron blocking layer, which is a semiconductor layer formed on the active layer; And
A light emitting device comprising an n-type semiconductor layer formed on the electron blocking layer,
Further comprising an electron overflow prevention layer formed between the active layer and the p-type semiconductor layer,
The band gap energy of the overflow prevention layer is greater than the band gap energy of the n-type semiconductor layer and less than the band gap energy of the electron blocking layer.

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