KR101667925B1 - Light emitting device and light emitting device package - Google Patents

Abstract

A second conductivity type semiconductor layer formed on the light emitting layer; and a light emitting layer formed on the first conductivity type semiconductor layer, the light emitting layer, and the light emitting layer, the quantum well layer and the quantum barrier Layer lattice constant of the first conductivity type semiconductor layer or the second conductivity type semiconductor layer is greater than a planar lattice constant of the quantum barrier layer and less than a planar lattice constant of the quantum well layer.

Description

[0001] LIGHT EMITTING DEVICE AND LIGHT EMITTING DEVICE PACKAGE [0002]

Embodiments relate to a light emitting device and a light emitting device package.

BACKGROUND ART Light emitting devices such as a light emitting diode (LD) or a laser diode using semiconductor materials of Group 3-5 or 2-6 group semiconductors are widely used for various colors such as red, green, blue, and ultraviolet And it is possible to realize white light rays with high efficiency by using fluorescent materials or colors, and it is possible to realize low energy consumption, semi-permanent life time, quick response speed, safety and environment friendliness compared to conventional light sources such as fluorescent lamps and incandescent lamps .

Therefore, a transmission module of the optical communication means, a light emitting diode backlight replacing a cold cathode fluorescent lamp (CCFL) constituting a backlight of an LCD (Liquid Crystal Display) display device, a white light emitting element capable of replacing a fluorescent lamp or an incandescent lamp Diode lighting, automotive headlights, and traffic lights.

The embodiments are intended to provide a light emitting device and a light emitting device package with high efficiency by effectively mitigating the compressive stress applied to the quantum well layer in the light emitting layer and significantly improving the spontaneous emission efficiency of the quantum well layer.

The light emitting layer includes a quantum well layer and a quantum barrier layer. The first conductive semiconductor layer includes a first conductive semiconductor layer, a light emitting layer formed on the first conductive semiconductor layer, a second conductive semiconductor layer formed on the light emitting layer, And the planar direction lattice constant of the conductive type semiconductor layer or the second conductivity type semiconductor layer is larger than the planar direction lattice constant of the quantum barrier layer and smaller than the planar direction lattice constant of the quantum well layer.

At least one of the first conductivity type semiconductor layer, the second conductivity type semiconductor layer, the quantum well layer and the quantum barrier layer includes indium (In), and the first conductivity type semiconductor layer or the second conductivity type semiconductor layer The indium content may be greater than the indium content of the quantum barrier layer and less than the indium content of the quantum well layer.

Here, the quantum well layer may be In _x Ga _1-x N, the quantum barrier layer may be In _y Ga _1-y N, the first conductivity type semiconductor layer or the second conductivity type semiconductor layer may be In _z Ga _1-z N , Indium (In) x, y, and z may have a composition of x>z> y.

At least one of the quantum well layer and the quantum barrier layer includes indium (In), and the indium content of the quantum barrier layer May be less than the indium content of the quantum well layer.

Here, the quantum well layer is In _x Ga _1-x N, the quantum barrier layer is In _y Ga _1-y N, and the first conductivity type semiconductor layer or the second conductivity type semiconductor layer is made of Mg _z Zn _1-z O , Indium (In) x, and y may have the composition x> y.

Any one of the first and second conductivity type semiconductor layers, the quantum well layer and the quantum barrier layer may have different energy band gaps.

Here, the energy band gap of the quantum barrier layer is larger than the energy band gap of the quantum well layer, and the energy band gap of the first conductivity type semiconductor layer or the second conductivity type semiconductor layer may be larger or smaller than the energy band gap of the quantum barrier layer have.

In addition, the luminescent layer may be a multiple quantum well structure in which a quantum well layer and a quantum barrier layer are repeatedly formed. At least one of the quantum barrier layer and the quantum well layer may have a lattice constant of the first and second conductivity type semiconductors The distance from one of the layers can be gradually increased.

Further, the plane direction lattice constant of at least one of the quantum barrier layer and the quantum well layer may be gradiently varied in the thickness direction.

The light emitting layer includes a quantum well layer and a quantum barrier layer, and the quantum well layer and the quantum well layer are formed on the first conductivity type semiconductor layer, the light emitting layer formed on the first conductivity type semiconductor layer, the second conductivity type semiconductor layer formed on the light emitting layer, The barrier layer has a tensile stress with respect to the first conductivity type semiconductor layer or the second conductivity type semiconductor layer and the quantum well layer provides a light emitting element having compressive stress with respect to the first conductivity type semiconductor layer or the second conductivity type semiconductor layer do.

Here, the planar lattice constant of the first conductivity type semiconductor layer or the second conductivity type semiconductor layer may be larger than the planar lattice constant of the quantum barrier layer and less than the planar lattice constant of the quantum well layer.

By forming the plane direction lattice constant of the semiconductor layer to be greater than the planar lattice constant of the quantum barrier layer and less than the planar lattice constant of the quantum well layer, the embodiments have a tensile stress on the semiconductor layer, The layers have a compressive stress on the semiconductor layer and cancel each other out.

That is, due to the semiconductor layer having the lattice constant between the quantum well layer and the quantum barrier layer, the quantum barrier layer having tensile stress serves as a stress buffer layer for buffering the compressive stress of the quantum well layer.

Therefore, the internal stress relaxation reduces the internal stress field acting on the quantum well layer, thereby reducing the spatial separation of the wave function of electrons and holes in the quantum well layer, thereby increasing the spontaneous emission efficiency of the light emitting device.

In addition, by forming the quantum barrier layer and the quantum well layer in such a manner that the lattice constants in the plane direction of the quantum well layer are varied in the thickness direction, an energy band structure can be formed in which electrons and protons can be implanted in a satisfactory manner, The device can be manufactured.

1A and 1B are structural cross-sectional views illustrating a light emitting device according to an embodiment of the present invention.
FIGS. 2 and 3 are views showing stress states of respective layers according to a difference in lattice constant
4 is a graph showing the band gap energy according to the in-plane lattice constant of the InGaN semiconductor layer
5 is a graph showing the band gap energy according to the plane direction lattice constant of the MgZnO semiconductor layer
6A and 6B are energy band diagrams of the light emitting device according to FIG.
7 to 9 are views showing the lattice constant difference of each layer of the light emitting device according to another embodiment
Figs. 10-14 show energy band diagrams < RTI ID = 0.0 >
15 to 17 are views showing the lattice constant difference of each layer of the light emitting device according to another embodiment
Figs. 18-20 illustrate the energy band diagrams < RTI ID = 0.0 >
21 to 23 are views showing the lattice constant difference of each layer of the light emitting device according to another embodiment
Figs. 24-26 illustrate the energy band diagrams < RTI ID = 0.0 >
FIGS. 27 to 29 are views showing the lattice constant difference of each layer of the light emitting device according to another embodiment
30 to 32 show the energy band diagram according to Figs. 27 to 29
33A and 33B are graphs comparing the compressive stresses of a general quantum well structure and a stress buffering quantum well structure according to the present invention
34 is a graph showing a comparison between a general quantum well structure and an amount of an optical matrix element represented by a plane direction wave vector function of a stress buffering quantum well structure according to the present invention
35 is a graph comparing a spontaneous emission rate with a general quantum well structure and a stress buffering quantum well structure according to the present invention
36 and 37 are graphs showing the degree of compressive stress applied to the quantum well according to the Mg ratio of the MgZnO semiconductor layer
38 is a view showing a horizontal light emitting element having a stress buffering type quantum well structure
39 is a view showing a vertical light emitting device having a stress buffering type quantum well structure
40 is a view showing a hybrid light emitting device having a stress buffering type quantum well structure
41 is a sectional view of an embodiment of a light emitting device package
42 is a view showing an embodiment of a lighting device having a light emitting element

Hereinafter, embodiments will be described with reference to the accompanying drawings.

In the description of the embodiments, it is to be understood that each layer (film), region, pattern or structure is formed "on" or "under" a substrate, each layer The terms " on "and " under " encompass both being formed" directly "or" indirectly " In addition, the criteria for above or below each layer will be described with reference to the drawings.

The thickness and size of each layer in the drawings are exaggerated, omitted, or schematically shown for convenience and clarity of explanation. Also, the size of each component does not entirely reflect the actual size.

1A and 1B are sectional views illustrating a light emitting device according to an embodiment of the present invention. FIG. 1A is a light emitting device having a light emitting layer having a single quantum well structure, and FIG. 1B is a light emitting device having a multiple quantum well structure.

1A and 1B, the light emitting device includes a first conductivity type semiconductor layer 10, a light emitting layer 30, and a second conductivity type semiconductor layer 50, and the light emitting layer 30 includes a quantum well layer (33) and a quantum barrier layer (31).

The light emitting layer 30 may be a single quantum well structure having one quantum well layer 33 as shown in FIG. 1A, or may be a multi quantum well structure having a plurality of quantum well layers 33 as shown in FIG. Structure (multi-quantum well).

Here, the first conductive semiconductor layer 10 may be an n-type semiconductor layer as an electron injecting layer and the second conductive semiconductor layer 50 may be a p-type semiconductor as a hole injecting layer. Conversely, the first conductive semiconductor layer 10 may be a p-type semiconductor as a hole injection layer, and the second conductivity type semiconductor layer 50 may be an n-type semiconductor as an electron injection layer.

The thickness of the quantum barrier layer 31 is about 5-15 nm, the thickness of the quantum well layer 33 is about 1.5-5 nm, the thickness of the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 is And preferably about 10 nm to 200 mu m.

This is because if the thicknesses of the quantum barrier layer 31 and the quantum well layer 33 are out of the above ranges, injection and bonding of electrons and holes are difficult, and the luminous efficiency may be lowered.

The planar lattice constant of the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 is larger than the planar lattice constant of the quantum barrier layer 31 and the planar direction lattice constant of the quantum well layer 33 Is preferably smaller than a constant.

In addition, the planar lattice constant of the quantum barrier layer 31 may be smaller than the lattice constant of the quantum well layer 33.

Here, the planar direction lattice constant of the quantum barrier layer 31 is about 3.12 - 3.25 ANGSTROM, and the planar direction lattice constant of the quantum well layer 33 is about 3.2 SIMILAR 3.55 ANGSTROM. The first and second conductivity type semiconductor layers 10, 50) may be about 3.2 - 3.4 Å.

As described above, the plane direction lattice constant of the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 is made different from the plane lattice constant of the quantum barrier layer 31 and the quantum well layer 33 The reason is as follows.

2 and 3 are diagrams showing stress states of respective layers according to the difference in lattice constant. FIG. 2 is a graph showing the relationship between the surface direction lattice constant of the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50, And FIG. 3 is a view showing a stress state when the planar lattice constant of the barrier layer 31 is the same. FIG. 3 is a view showing a stress state when the planar lattice constant of the barrier layer 31 is the same. Is greater than the planar lattice constant of the barrier layer 31 and less than the planar lattice constant of the quantum well layer 33. [

2, when the planar direction lattice constant of the quantum barrier layer 31 is smaller than the planar direction lattice constant of the quantum well layer 33 in the light emitting layer including the quantum barrier layer 31 and the quantum well layer 33 , The quantum well layer 33 is subjected to stress.

For example, when GaN and InN, which are nitride semiconductor materials, grow in the form of thin films with the same crystallographic orientation on a heterogeneous bulk substrate, the difference in their plane direction lattice constants becomes as large as about 10%.

In other words, the in-plane lattice constant of InN is about 10% larger than that of GaN.

Therefore, the in-plane lattice constant of the InGaN quantum well layer formed by mixing GaN and InN at a certain ratio becomes larger than the planar lattice constant of the GaN quantum barrier layer.

Therefore, in the light emitting layer of the InGaN quantum well layer / GaN quantum barrier layer structure formed on the first and second conductivity type GaN semiconductor layers, the InGaN quantum well layer undergoes a severe compressive stress.

Thus, the severe compressive stress acting on the InGaN quantum well layer generates a large internal field and modifies the energy band structure of the InGaN quantum well layer. As a result, electrons and holes in the InGaN quantum well layer are spatially So that the spontaneous emission rate is remarkably lowered.

Therefore, in order to effectively relax the compressive stress of the InGaN quantum well layer, the surface direction lattice constant of the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50, as shown in FIG. 3, Direction lattice constant of the quantum well layer 33 and smaller than the planar lattice constant of the quantum well layer 33. [

At least one of the first conductivity type semiconductor layer 10, the second conductivity type semiconductor layer 50, the quantum well layer 33, and the quantum barrier layer 31 may be formed as an example for adjusting the surface direction lattice constant And the indium content of the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 is larger than the indium content of the quantum barrier layer 31 and the indium content of the quantum well layer 33 It can be formed to be smaller than the indium content.

Here, the quantum well layer 33 is made of In _x Ga _1-x N, the quantum barrier layer 31 is made of In _y Ga _1-y N, the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 ) it is preferably may be of in _z Ga _1-z N, an indium (in) composition of the x, y, z are x>z> y.

The composition range of indium (In) x, y, and z can be adjusted to 0 ≤ x, y, z ≤ 0.3, the composition range of indium (In) x is 0 <x ≤ 0.3, 0? Y? 0.1, and the composition range of indium (In) z may be 0 <z <0.3.

FIG. 4 is a graph showing the band gap energy according to the in-plane lattice constant of the InGaN semiconductor layer. As shown in FIG. 4, by adjusting the content of indium (In) of InGaN within a certain range, Can be adjusted.

Therefore, since the in-plane lattice constant of the InGaN semiconductor layer is larger than the in-plane lattice constant of the InGaN quantum barrier layer, the InGaN quantum barrier layer is subjected to tensile stress, and the InGaN quantum well layer has the in- Direction lattice constant of the InGaN quantum well layer, the InGaN quantum well layer undergoes compressive stress.

At this time, the tensile stress acting on the quantum barrier layer partially cushions the compressive stress acting on the quantum well layer.

This internal stress relaxation reduces the internal stress field acting on the quantum well layer, which in turn reduces the spatial separation of the wave function of electrons and holes in the quantum well layer, thereby increasing the spontaneous emission efficiency of the light emitting device.

In another embodiment, the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 includes magnesium (Mg), and at least one of the quantum well layer 33 and the quantum barrier layer 31 And the indium content of the quantum barrier layer 31 is preferably smaller than the indium content of the quantum well layer 33. In addition,

Here, the quantum well layer 33 is made of In _x Ga _1-x N, the quantum barrier layer 31 is made of In _y Ga _1-y N, the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 ) Is made of Mg _z Zn _1-z O, and the composition of indium (In) x, y is preferably x> y.

The composition range of indium (In) x is 0 <x ≦ 0.3, the composition range of indium (In) y is 0 ≦ y ≦ 0.1, and the composition range of magnesium (Mg) have.

FIG. 5 is a graph showing the band gap energy according to the planar lattice constant of the MgZnO semiconductor layer. As shown in FIG. 5, by adjusting the content of magnesium (Mg) in MgZnO within a certain range, Can be adjusted.

Therefore, since the in-plane lattice constant of the MgZnO semiconductor layer is larger than the in-plane lattice constant of the InGaN quantum barrier layer, the InGaN quantum barrier layer is subjected to tensile stress, and the InGaN quantum well layer has the in- Direction lattice constant of the InGaN quantum well layer, the InGaN quantum well layer undergoes compressive stress.

At this time, the tensile stress acting on the quantum barrier layer partially cushions the compressive stress acting on the quantum well layer.

This internal stress relaxation reduces the internal stress field acting on the quantum well layer, which in turn reduces the spatial separation of the wave function of electrons and holes in the quantum well layer, thereby increasing the spontaneous emission efficiency of the light emitting device.

In another embodiment of the present invention, at least one of the first conductivity type semiconductor layer, the second conductivity type semiconductor layer, the quantum well layer, and the quantum barrier layer includes indium (In) The second conductivity type semiconductor layer may be configured to include aluminum (Al).

Here, the indium content of the first conductivity type semiconductor layer or the second conductivity type semiconductor layer may be larger than the indium content of the quantum barrier layer and smaller than the indium content of the quantum well layer.

In some cases, the indium content of the first conductivity type semiconductor layer or the second conductivity type semiconductor layer may be smaller than the indium content of the quantum barrier layer and the indium content of the quantum well layer.

For example, the quantum well layer may be In _x Ga _1-x N, the quantum barrier layer may be In _y Ga _1-y N, the first conductivity type semiconductor layer or the second conductivity type semiconductor layer may be In _z Al _a Ga _1-za N, and the composition of indium (In) x, y, and z may be x>z> y.

6A and 6B are energy band diagrams of the light emitting device according to FIG. 1B. As shown in FIGS. 6A and 6B, any one of the first and second conductivity type semiconductor layers 10 and 50, The quantum barrier layer 33, and the quantum barrier layer 31 have different energy band gaps.

That is, the energy band gap of the quantum barrier layer 31 is larger than the energy band gap of the quantum well layer 33, and the energy band gap of the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 is May be larger or smaller than the energy bandgap of the quantum barrier layer (31).

Here, the energy band gap of the quantum barrier layer 31 is about 3.0-5.0 eV, the energy band gap of the quantum well layer 33 is about 0.65-3.2 eV, the first conductivity type semiconductor layer 10, The energy band gap of the semiconductor layer 50 may be about 2.0 - 8.0 eV.

7 to 9 are diagrams showing the lattice constant difference of each layer of the light emitting device according to another embodiment.

7 to 9, the plane direction lattice constant of the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 is larger than the plane direction lattice constant of the quantum barrier layer 31, Is smaller than the planar lattice constant of the well layer (33).

In addition, the planar lattice constant of at least one of the quantum barrier layer 31 and the quantum well layer 33 may gradually increase from one of the first and second conductivity type semiconductor layers 10 and 50 .

Here, FIG. 7 shows that the planar lattice constant of the quantum barrier layer 31 gradually increases as the distance from the one of the first and second conductivity type semiconductor layers 10 and 50 increases, and all the quantum well layers 33 have the same indium content, the indium content gradually increases as the quantum barrier layer 31 is further away from any one of the first and second conductivity type semiconductor layers 10, 50.

That is, the quantum barrier layer 31, which is distant from the first and second conductivity type semiconductor layers 10 and 50 than the indium content of the quantum barrier layer 31 adjacent to the first and second conductivity type semiconductor layers 10 and 50, And the quantum barrier layers 31 adjacent to each other may have different indium contents from each other.

8 is a diagram showing that the planar lattice constant of the quantum well layer 33 gradually increases as the distance from the one of the first and second conductivity type semiconductor layers 10 and 50 increases. The indium content gradually increases as the quantum well layer 33 is away from any one of the first and second conductivity type semiconductor layers 10 and 50. However,

That is, the quantum well layer 33, which is distant from the first and second conductivity-type semiconductor layers 10 and 50 than the indium content of the quantum well layer 33 adjacent to the first and second conductivity type semiconductor layers 10 and 50, And the quantum well layers 33 adjacent to each other may have different indium contents from each other.

Next, FIG. 9 is a view showing that the planar lattice constant of the quantum barrier layer 31 and quantum well layer 33 gradually increases as the distance from the one of the first and second conductivity type semiconductor layers 10 and 50 increases , The indium content gradually increases as the quantum well layer 33 and the quantum barrier layer 31 are away from any one of the first and second conductivity type semiconductor layers 10 and 50.

That is, the indium content of the quantum well layer 33 and the quantum barrier layer 31 adjacent to the first and second conductivity type semiconductor layers 10 and 50 is larger than the indium content of the first and second conductivity type semiconductor layers 10 and 50 The indium content of the remained quantum well layer 33 and the quantum barrier layer 31 is higher and the quantum well layers 33 adjacent to each other or the quantum barrier layers 31 adjacent to each other may have different indium contents from each other.

Although not shown, in some cases, at least one of the remaining quantum well layers 33 except the first quantum well layer 33 adjacent to the first and second conductivity type semiconductor layers 10 and 50, You can also have constants.

Alternatively, at least one of the quantum barrier layers 31 other than the first quantum barrier layer 31 adjacent to the first and second conductivity type semiconductor layers 10 and 50 may have a different lattice constant.

Figs. 10 to 14 are energy band diagrams according to Figs. 7 to 9. Fig.

10 is an energy band diagram according to the lattice constant difference in FIG. 7, in which the energy band gap of the quantum barrier layer 31 is the energy band gap of the first and second conductivity type semiconductor layers 10 and 50 It can be seen that the farther away from either one, the smaller becomes.

FIG. 11 is an energy band diagram according to the lattice constant difference in FIG. 8, in which the energy band gap of the quantum well layer 33 is the energy band gap of the first and second conductivity type semiconductor layers 10 and 50 It can be seen that the farther away from either one, the smaller becomes.

FIG. 12 is an energy band diagram according to the lattice constant difference in FIG. 9, in which the energy band gap of the quantum barrier layer 31 and the quantum well layer 33 is different from that of the first and second conductivity type semiconductors And gradually decreases as the distance from any one of the layers 10 and 50 increases.

FIGS. 13 and 14 are energy band diagrams according to another embodiment. FIG. 13 is a graph showing the energy band diagram of the remaining quantum barrier layers except for the first quantum barrier layer 31 adjacent to the first and second conductivity type semiconductor layers 10 and 50 31 may be different from each other in energy band gap, and FIG.

14 is a graph showing that the energy band gap of at least one of the quantum well layers 33 other than the first quantum well layer 33 adjacent to the first and second conductivity type semiconductor layers 10 and 50 may be different from each other Fig.

15 to 17 are diagrams showing the lattice constant difference of each layer of the light emitting device according to another embodiment.

15 to 17, the plane direction lattice constant of the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 is larger than the plane direction lattice constant of the quantum barrier layer 31, Is smaller than the planar lattice constant of the well layer (33).

In addition, the plane direction lattice constant of at least one of the quantum barrier layer 31 and the quantum well layer 33 may be formed so as to be gradated in the thickness direction.

15 shows a case where the first quantum barrier layer 31a has a planar direction lattice constant in the thickness direction toward the quantum well layer 33a from the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 And the second quantum barrier layer 31b gradually decreases in planar direction lattice constant in the thickness direction from the edge region toward the center region, all the quantum well layers 33 have the same indium content, The indium content of the quantum barrier layer 31 gradually varies in the thickness direction.

That is, in the case of the first quantum barrier layer 31a located between the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 and the quantum well layer 33a, The indium content gradually increases in the thickness direction from the layers 10 and 50 toward the quantum well layer 33a.

In the case of the second quantum barrier layer 31b located between the first quantum well layer 33a and the second quantum well layer 33b, the thickness from the edge region toward the center region of the second quantum barrier layer 31b The indium content gradually decreases in the direction of the orientation.

16 shows that the quantum well layer 33 gradually increases in planar direction lattice constant in the thickness direction from the edge region to the center region of the quantum well layer 33. All the quantum barrier layers 31 have the indium content Are the same, but the quantum well layer 31 gradually changes in indium content in the thickness direction.

That is, in the case of the quantum well layer 33 located between the first quantum barrier layer 31a and the second quantum barrier layer 31b, the indium content in the thickness direction toward the center region from the edge region of the quantum well layer 33 .

17 is a diagram showing the difference in planar lattice constant including both the quantum barrier layer 31 of FIG. 15 and the quantum well layer 33 of FIG. 16, in which the quantum barrier layer 31 and the quantum well layer 33, The indium content gradually changes in the thickness direction.

18 to 20 are energy band diagrams according to Figs. 15 to 17. Fig.

FIG. 18 is an energy band diagram according to the lattice constant difference in FIG. 15, FIG. 19 is an energy band diagram according to the lattice constant difference in FIG. 16, and FIG. 20 is an energy band diagram according to the lattice constant difference in FIG.

As shown in FIGS. 18 to 20, it can be seen that the energy band gap of the quantum barrier layer 31 and the quantum well layer 33 gradually change in the thickness direction.

21 to 23 are views showing lattice constant differences of respective layers of a light emitting device according to another embodiment.

21 to 23, the plane direction lattice constant of the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 is larger than the plane direction lattice constant of the quantum barrier layer 31, Is smaller than the planar lattice constant of the well layer (33).

In addition, the plane direction lattice constant of at least one of the quantum barrier layer 31 and the quantum well layer 33 may be formed so as to be gradated in the thickness direction.

21 shows that the quantum barrier layer 31 has a lattice constant increasing in the plane direction from the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 toward the quantum well layer 33 And the quantum barrier layer 31 is formed from the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 to the quantum well layer 33. In this case, The indium content gradually increases in the direction of the thickness toward the recess 33.

That is, in the case of the first quantum barrier layer 31 located between the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 and the quantum well layer 33, The indium content at the interface of the quantum barrier layer 31 adjacent to the layers 10 and 50 may be greater than the indium content at the interface of the quantum barrier layer 31 adjacent to the quantum well layer 33. [

22 is a view showing that the quantum well layer 33 gradually increases in planar direction lattice constant in the thickness direction toward the second quantum barrier layer 31b from the first quantum barrier layer 31a, ) Have the same indium content but the quantum well layer 33 gradually increases in indium content in the thickness direction from the first quantum barrier layer 31a to the second quantum barrier layer 31b.

That is, in the case of the first quantum well layer 33 located between the first quantum barrier layer 31a and the second quantum barrier layer 31b, the interface between the quantum well layer 33 adjacent to the first quantum barrier layer 31a The indium content at the interface of the quantum well layer 33 adjacent to the second quantum barrier layer 31b is greater than the indium content at the second quantum well layer 33b.

23 is a view showing that the planar direction lattice constant gradually increases in the thickness direction away from the first and second conductivity type semiconductor layers 10 and 50 by the quantum barrier layer 31 and the quantum well layer 33, The layer 31 and the quantum well layer 33 gradually increase in indium content in the thickness direction away from the first and second conductivity type semiconductor layers 10 and 50.

Figs. 24 to 26 are energy band diagrams according to Figs. 21 to 23. Fig.

FIG. 24 is an energy band diagram according to the lattice constant difference in FIG. 21, FIG. 25 is an energy band diagram according to the lattice constant difference in FIG. 22, and FIG. 26 is an energy band diagram according to the lattice constant difference in FIG.

As shown in Figs. 24 to 26, it can be seen that the energy band gap of the quantum barrier layer 31 and quantum well layer 33 gradually varies in the thickness direction.

27 to 29 are views showing lattice constant difference of each layer of the light emitting device according to another embodiment.

27 to 29, the plane direction lattice constant of the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 is larger than the plane direction lattice constant of the quantum barrier layer 31, Is smaller than the planar lattice constant of the well layer (33).

In addition, the plane direction lattice constant of at least one of the quantum barrier layer 31 and the quantum well layer 33 may be formed so as to be gradated in the thickness direction.

27 is a plan view of the first quantum barrier layer 31a in the thickness direction from the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 toward the first quantum well layer 33a, And the second quantum barrier layer 31b gradually decreases in planar direction lattice constant in the thickness direction from the first quantum well layer 33a to the second quantum well layer 33b, The quantum well layer 33 has indium contents equal to each other, but the quantum barrier layer 31 gradually varies in indium content in the thickness direction.

That is, in the case of the first quantum barrier layer 31a located between the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 and the first quantum well layer 33a, Type semiconductor layer 10, 50 gradually increases in the thickness direction toward the first quantum well layer 33a.

In the case of the second quantum barrier layer 31b located between the first quantum well layer 33a and the second quantum well layer 33b, a second quantum well layer 33b is formed from the first quantum well layer 33a, The indium content gradually decreases in the direction of the thickness toward the substrate.

28 shows that the first quantum well layer 33a gradually increases in planar direction lattice constant in the thickness direction from the first quantum barrier layer 31a to the second quantum barrier layer 31b and the second quantum well layer 33b ) Of the quantum well layer 33 gradually decreases in the direction of thickness in the thickness direction. In all the quantum barrier layers 31, the indium contents are equal to each other, while the quantum well layer 33 gradually changes in indium content in the thickness direction.

That is, in the case of the first quantum well layer 33a located between the first quantum barrier layer 31a and the second quantum barrier layer 31b, the indium content gradually increases in the thickness direction, and the second quantum barrier layer 31b ) And the second quantum well layer 33b located between the third quantum barrier layer, the indium content gradually decreases in the thickness direction.

29 is a view showing the difference in planar lattice constant including both the quantum barrier layer 31 of FIG. 27 and the quantum well layer 33 of FIG. 29. The quantum barrier layer 31 and the quantum well layer 33 The indium content gradually changes in the thickness direction.

30 to 32 are energy band diagrams according to Figs. 27 to 29. Fig.

FIG. 30 is an energy band diagram according to the lattice constant difference in FIG. 27, FIG. 31 is an energy band diagram according to the lattice constant difference in FIG. 28, and FIG. 32 is an energy band diagram according to the lattice constant difference in FIG.

As shown in FIGS. 30 to 32, it can be seen that the energy band gap of the quantum barrier layer 31 and the quantum well layer 33 gradually change in the thickness direction.

As described above, the embodiments of the present invention allow the quantum barrier layer to have a tensile stress with respect to the semiconductor layer by forming the surface direction lattice constant of the semiconductor layer larger than the surface direction lattice constant of the quantum barrier layer and smaller than the surface direction lattice constant of the quantum well layer. With the stress, the quantum well layers have a compressive stress on the semiconductor layer and cancel each other out.

That is, due to the semiconductor layer having the lattice constant between the quantum well layer and the quantum barrier layer, the quantum barrier layer having tensile stress serves as a stress buffer layer for buffering the compressive stress of the quantum well layer.

Therefore, the internal stress relaxation reduces the internal stress field acting on the quantum well layer, thereby reducing the spatial separation of the wave function of electrons and holes in the quantum well layer, thereby increasing the spontaneous emission efficiency of the light emitting device.

In addition, by forming the quantum barrier layer and the quantum well layer in such a manner that the lattice constants in the plane direction of the quantum well layer are varied in the thickness direction, an energy band structure can be formed in which electrons and protons can be implanted in a satisfactory manner, The device can be manufactured.

33A and 33B are graphs comparing compressive stresses of a general quantum well structure and a stress buffering quantum well structure according to the present invention.

33A is a potential profile and a wave function distribution diagram of the first conduction band subband (C1) and the first phase transition band (HH1) for the InGaN / GaN quantum well structure on a general GaN semiconductor layer, (C1) and the first potential vs. subband (HH1) for the InGaN / InGaN quantum well structure on the stress buffered InGaN semiconductor layer according to the following equation (1).

In the general quantum well structure, due to the severe compressive stress acting on the InGaN quantum well layer, a large internal field is generated to change the energy band structure of the InGaN quantum well layer.

Therefore, as shown in FIG. 33A, due to the deformation of the energy band structure, it can be seen that the energy band has a slope having a steep slope, and a compressive stress is about 2.74% in a general quantum well structure.

On the other hand, in the stress buffering quantum well structure according to the present invention, since the in-plane lattice constant of the InGaN semiconductor layer is larger than the planar lattice constant of the quantum barrier layer and smaller than the planar lattice constant of the quantum well layer, The tensile stress acting partially compensates the compressive stress applied to the quantum well layer, thereby reducing the internal stress field acting on the quantum well layer.

Therefore, as shown in Fig. 33B, it can be seen that the inclination of the slope of the energy band is relaxed as compared with the general quantum well structure, and the compressive stress is about 1.18%, indicating that the compressive stress is smaller than that of a general quantum well structure .

Fig. 34 is a graph comparing the quantum well structure of the general quantum well with the quantities of optical matrix elements represented by the surface direction wave vector functions of the stress buffering quantum well structure according to the present invention. Fig. 35 is a graph showing the relationship between the general quantum well structure and the stress And a spontaneous emission rate for a buffered quantum well structure.

As shown in Fig. 34, there are many more optical matrix elements of the stress buffering type quantum well structure according to the present invention than the optical matrix elements of the general quantum well structure.

These results are due to the reduction of the internal stress field in the light emitting layer as the degree of crystal lattice mismatch decreases.

As a result, as shown in FIG. 35, it can be seen that the spontaneous luminous efficiency of the light emitting device having the stress buffering type quantum well structure according to the present invention is greatly increased compared to the spontaneous luminous efficiency of the light emitting device having a general quantum well structure have.

36 and 37 are graphs showing the degree of compressive stress applied to the quantum well according to the Mg ratio of the MgZnO semiconductor layer.

FIG. 36 is a graph showing the degree of compressive stress applied to the quantum well depending on the Mg ratio of the MgZnO semiconductor layer at a constant quantum well thickness, and FIG. 37 is a graph showing the degree of compressive stress applied to the quantum well, This is a graph showing the degree of compressive stress applied to the quantum well.

As shown in FIGS. 36 and 37, it can be seen that as the Mg ratio of the MgZnO semiconductor layer increases, the compressive stress applied to the quantum well decreases.

36 and 37 are graphs showing the result of calculating the stress acting on the quantum well in the range of about 0 to 0.1 in the case of considering a green LED having an emission wavelength of about 530 nm as an example, And the stress acting on the quantum well increases as the flow rate of indium increases.

38 is a view showing a horizontal light emitting device having a stress buffering type quantum well structure.

The first conductivity type semiconductor layer 10, the light emitting layer 30 and the second conductivity type semiconductor layer 50 are formed on the substrate 1 and the light emitting layer 30 is formed on the quantum well layer 33 and a quantum barrier layer 31.

A first electrode 60 is formed on the first conductivity type semiconductor layer 10 and a second electrode 70 is formed on the second conductivity type semiconductor layer 50.

Here, the quantum barrier layer 31 has a tensile stress with respect to the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50, and the quantum well layer 33 has tensile stress with respect to the first conductivity type semiconductor layer 10 ) Or the second conductivity type semiconductor layer (50).

The planar lattice constant of the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 is larger than the planar lattice constant of the quantum barrier layer 31 and the planar direction lattice constant of the quantum well layer 33 Is preferably smaller than a constant.

For example, sapphire (Al ₂ O ₃ ), GaN, SiC, ZnO, Si, GaP, InP, Ga ₂ O ₃ , and GaAs may be used as the substrate 1.

In addition, an undoped semiconductor layer (not shown) may be further formed under the first conductivity type semiconductor layer 10, but the present invention is not limited thereto.

The first conductivity type semiconductor layer 10 may be selected from GaN, AlN, AlGaN, InGaN, InN, InAlGaN and AlInN and may be doped with an n-type dopant such as Si, Ge, Sn, Se or Te.

The undoped semiconductor layer is formed to improve the crystallinity of the first conductivity type semiconductor layer 10. The n-type dopant is not doped and has a lower electrical conductivity than the first conductivity type semiconductor layer 10 May be the same as the first conductivity type semiconductor layer 10.

The light emitting layer 30 may include at least one of a quantum wire structure, a quantum dot structure, a single quantum well structure or a multi quantum well structure (MQW).

The light emitting layer 30 can generate light by energy generated in the recombination process of electrons and holes provided from the first conductivity type semiconductor layer 10 and the second conductivity type semiconductor layer 50.

The second conductive semiconductor layer 50 may be selected from GaN, AlN, AlGaN, InGaN, InN, InAlGaN, and AlInN, and may be doped with a p-type dopant such as Mg, Zn, Ca, .

Here, the first conductivity type semiconductor layer 10 may be a p-type semiconductor layer and the second conductivity type semiconductor layer 50 may be an n-type semiconductor layer, as described above.

In addition, a third conductive semiconductor layer (not shown) including an n-type or p-type semiconductor layer may be formed on the first conductivity type semiconductor layer 10. Accordingly, pn, npn, and pnp junction structures.

In addition, the doping concentrations of the conductive dopants in the first conductivity type semiconductor layer 10 and the second conductivity type semiconductor layer 50 can be uniform or non-uniform.

That is, the structure of the plurality of semiconductor layers may be variously formed, but is not limited thereto.

The first electrode 60 and the second electrode 70 may be formed of at least one of aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), copper (Cu) Layer structure or a multi-layer structure.

39 is a view showing a vertical light emitting device having a stress buffering type quantum well structure.

A second conductivity type semiconductor layer 50, a light emitting layer 30, and a first conductivity type semiconductor layer 10 are formed on a support layer 80 formed of a metal or a conductive semiconductor layer, The light emitting layer 30 includes a quantum well layer 33 and a quantum barrier layer 31.

A first electrode 60 is formed on the first conductivity type semiconductor layer 10 and a second electrode 70 is formed between the second conductivity type semiconductor layer 50 and the support layer 80.

The second electrode 70 may be composed of an ohmic electrode 71 and a reflective electrode 72 and the ohmic electrode 71 may be a transparent electrode.

Here, the quantum barrier layer 31 has a tensile stress with respect to the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50, and the quantum well layer 33 has tensile stress with respect to the first conductivity type semiconductor layer 10 ) Or the second conductivity type semiconductor layer (50).

The planar lattice constant of the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 is larger than the planar lattice constant of the quantum barrier layer 31 and the planar direction lattice constant of the quantum well layer 33 Is preferably smaller than a constant.

40 is a view showing a hybrid light emitting device having a stress buffering type quantum well structure.

40, a first conductivity type semiconductor layer 10, a light emitting layer 30, and a second conductivity type semiconductor layer 50 are formed on a substrate 1, and the light emitting layer 30 is a quantum well layer 33 and a quantum barrier layer 31.

A first electrode 60 is formed on the first conductivity type semiconductor layer 10 and a second electrode 70 is formed between the substrate 1 and the first conductivity type semiconductor layer 10, -Type semiconductor layer 10 and the light emitting layer 30 to be contacted with the second conductivity type semiconductor layer 50.

That is, the second electrode 70 is contacted with the second conductive type semiconductor layer 50 through the hole formed to pass through the first conductive type semiconductor layer 10 and the light emitting layer 30.

The insulating film 80 is coated on the side surface of the hole, and the second electrode 70 is electrically insulated.

The quantum barrier layer 31 has a tensile stress with respect to the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 and the quantum well layer 33 has a tensile stress with respect to the first conductivity type semiconductor layer 10 ) Or the second conductivity type semiconductor layer (50).

The planar lattice constant of the first conductivity type semiconductor layer 10 or the second conductivity type semiconductor layer 50 is larger than the planar lattice constant of the quantum barrier layer 31 and the planar direction lattice constant of the quantum well layer 33 Is preferably smaller than a constant.

The substrate 1 may be made of a transparent material such as sapphire (Al ₂ O ₃ ), GaN, SiC, ZnO, Si, GaP, InP, Ga ₂ O ₃ , Or a conductive semiconductor layer.

Next, an undoped semiconductor layer (not shown) may be further formed between the first conductivity type semiconductor layer 10 and the second electrode 70, but the present invention is not limited thereto.

The first conductivity type semiconductor layer 10 may be selected from GaN, AlN, AlGaN, InGaN, InN, InAlGaN and AlInN and may be doped with an n-type dopant such as Si, Ge, Sn, Se or Te.

The undoped semiconductor layer is formed to improve the crystallinity of the first conductivity type semiconductor layer 10. The n-type dopant is not doped and has a lower electrical conductivity than the first conductivity type semiconductor layer 10 May be the same as the first conductivity type semiconductor layer 10.

The light emitting layer 30 may include at least one of a quantum wire structure, a quantum dot structure, a single quantum well structure or a multi quantum well structure (MQW).

The light emitting layer 30 can generate light by energy generated in the recombination process of electrons and holes provided from the first conductivity type semiconductor layer 10 and the second conductivity type semiconductor layer 50.

The second conductive semiconductor layer 50 may be selected from GaN, AlN, AlGaN, InGaN, InN, InAlGaN, and AlInN, and may be doped with a p-type dopant such as Mg, Zn, Ca, .

Here, the first conductivity type semiconductor layer 10 may be a p-type semiconductor layer and the second conductivity type semiconductor layer 50 may be an n-type semiconductor layer, as described above.

In addition, a third conductive semiconductor layer (not shown) including an n-type or p-type semiconductor layer may be formed on the first conductivity type semiconductor layer 10. Accordingly, pn, npn, and pnp junction structures.

In addition, the doping concentrations of the conductive dopants in the first conductivity type semiconductor layer 10 and the second conductivity type semiconductor layer 50 can be uniform or non-uniform.

That is, the structure of the plurality of semiconductor layers may be variously formed, but is not limited thereto.

The first electrode 60 and the second electrode 70 may be formed of at least one of aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), copper (Cu) Layer structure or a multi-layer structure.

As described above, the embodiments of the present invention can provide a highly efficient light emitting device by effectively relaxing the compressive stress applied to the quantum well layer in the light emitting layer and drastically improving the spontaneous emission efficiency of the quantum well layer.

41 is a cross-sectional view of an embodiment of a light emitting device package.

41, a light emitting device package according to an embodiment includes a package body 320, a first electrode layer 311 and a second electrode layer 312 provided on the package body 320, a package body 320, The light emitting device 300 includes a first electrode layer 311 and a second electrode layer 312 electrically connected to the first electrode layer 311 and the second electrode layer 312 and a filler 340 surrounding the light emitting device 300.

Here, the package body 320 may be formed of a silicon material, a synthetic resin material, or a metal material, and an inclined surface may be formed around the light emitting device 300 to enhance light extraction efficiency.

The first electrode layer 311 and the second electrode layer 312 are electrically isolated from each other and provide power to the light emitting device 300.

The first electrode layer 311 and the second electrode layer 312 may reflect the light generated by the light emitting device 300 to increase the light efficiency and may be configured to discharge heat generated from the light emitting device 300 to the outside It can also play a role.

The light emitting device 300 may be mounted on the package body 320 or on the first electrode layer 311 or the second electrode layer 312.

The light emitting device 300 may be electrically connected to the first electrode layer 311 and the second electrode layer 312 by any one of wire, flip chip, and die bonding methods.

The filler 340 can surround and protect the light emitting device 300.

The filler 340 may include a phosphor to change the wavelength of light emitted from the light emitting device 300.

The light emitting device package may include at least one of the light emitting devices of the above-described embodiments, but may not be limited thereto.

A plurality of light emitting device packages according to the embodiments may be arranged on a substrate, and a light guide plate, a prism sheet, a diffusion sheet, and the like may be disposed on the light path of the light emitting device package.

Such a light emitting device package, a substrate, and an optical member can function as a light unit.

Still another embodiment may be implemented as a display device, an indicating device, a lighting system including the semiconductor light emitting device or the light emitting device package described in the above embodiments, for example, the lighting system may include a lamp, a streetlight .

Such an illumination system can be used as an illumination light for collecting light by focusing a plurality of LEDs. In particular, the illumination system can be embedded in a ceiling or a wall of a building and can be used as a back light (down light) have.

42, an illuminating device includes an LED (light emitting diode) light source 20 and a light emitting diode (LED) light source 20 which emits light from the LED light source 20, as shown in FIG. 42. FIG. And a shade (30) for setting an emission-directing angle of light.

The LED light source 20 may include at least one LED 22 provided on a printed circuit board 21 and a plurality of LEDs 22 are arranged on the circuit board 21 .

The shade 30 condenses the light emitted from the LED light source 20 to have a predetermined directional angle to be emitted through the opening, and the inner surface of the shade 30 may have a mirror surface.

Here, the LED light source 20 and the shade may be spaced apart by a predetermined distance d.

As described above, the illumination device can be used as an illumination light for collecting light by collecting a plurality of LEDs 22, and is particularly mounted on a ceiling or wall of a building to expose the opening side of the shade 30 (Down light) that can be used to make it possible.

The features, structures, effects and the like described in the embodiments are included in at least one embodiment of the present invention and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects and the like illustrated in the embodiments can be combined and modified by other persons skilled in the art to which the embodiments belong. Therefore, it should be understood that the present invention is not limited to these combinations and modifications.

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 illustration, It can be seen that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (24)

A first conductive semiconductor layer;
A light emitting layer formed on the first conductive semiconductor layer; And
And a second conductivity type semiconductor layer formed on the light emitting layer,
Wherein the light emitting layer comprises a quantum well layer and a quantum barrier layer,
At least one of the first conductivity type semiconductor layer, the second conductivity type semiconductor layer, the quantum well layer, and the quantum barrier layer includes indium (In)
Wherein the first conductivity type semiconductor layer or the second conductivity type semiconductor layer includes aluminum (Al)
The indium content of the first conductivity type semiconductor layer or the second conductivity type semiconductor layer is larger than the indium content of the quantum barrier layer and smaller than the indium content of the quantum well layer,
Wherein a plane direction lattice constant of the first conductivity type semiconductor layer or the second conductivity type semiconductor layer is larger than a planar direction lattice constant of the quantum barrier layer and smaller than a planar direction lattice constant of the quantum well layer. The method according to claim 1,
Wherein the planar direction lattice constant of the quantum barrier layer is in the range of 3.12 to 3.25 ANGSTROM, the planar lattice constant of the quantum well layer is in the range of 3.2 to 3.55 ANGSTROM, and the first and second conductivity type semiconductor layers are in the range of 3.2 to 3.4 ANGSTROM. . The method according to claim 1,
At least one of the first conductivity type semiconductor layer, the second conductivity type semiconductor layer, the quantum well layer, and the quantum barrier layer includes indium (In)
Wherein the indium content of the first conductivity type semiconductor layer or the second conductivity type semiconductor layer is larger than the indium content of the quantum barrier layer and smaller than the indium content of the quantum well layer. The method according to claim 1,
Wherein the quantum well layer is In _x Ga _1-x N, the quantum barrier layer is In _y Ga _1-y N, the first conductivity type semiconductor layer or the second conductivity type semiconductor layer is made of In _z Ga _1-z N And the composition of indium (In) x, y, z is x>z> y. 5. The method of claim 4,
The composition range of indium (In) x, y, and z is 0? X, y, z? 0.3. 5. The method of claim 4,
The composition range of indium (In) x is 0 <x ≦ 0.3, the composition range of indium (In) y is 0 ≦ y ≦ 0.1, and the composition range of indium (In) Light emitting element. The method according to claim 1,
Wherein the first conductivity type semiconductor layer or the second conductivity type semiconductor layer includes magnesium (Mg), at least one of the quantum well layer and the quantum barrier layer includes indium (In)
Wherein an indium content of the quantum barrier layer is smaller than an indium content of the quantum well layer. The method according to claim 1,
Wherein the quantum well layer is In _x Ga _1-x N, the quantum barrier layer is In _y Ga _1-y N, the first conductivity type semiconductor layer or the second conductivity type semiconductor layer is Mg _z Zn _1-z O And the composition of indium (In) x, y is x > y. 9. The method of claim 8,
Wherein the composition range of the indium (In) x is 0 <x ≦ 0.3, the composition range of the indium (In) y is 0 ≦ y ≦ 0.1 and the composition range of the magnesium (Mg) Light emitting element. delete The method according to claim 1,
Wherein the quantum well layer is In _x Ga _1-x N, the quantum barrier layer is In _y Ga _1-y N, the first conductivity type semiconductor layer or the second conductivity type semiconductor layer is In _z Al _a Ga _1-za N, and the composition of indium (In) x, y, and z is x>z> y. The method according to claim 1,
Wherein the energy band gap of the quantum barrier layer is larger than the energy band gap of the quantum well layer and the energy band gap of the first conductivity type semiconductor layer or the second conductivity type semiconductor layer is larger than the energy band gap of the quantum well layer Or smaller. The method according to claim 1,
Wherein the energy band gap of the quantum well layer is 3.0 to 5.0 eV, the energy band gap of the quantum well layer is 0.65 to 3.2 eV, and the energy band gap of the first conductivity type semiconductor layer or the second conductivity type semiconductor layer is 2.0 - 8.0 eV. The method according to claim 1,
Wherein the thickness of the quantum well layer is 5 to 15 nm, the thickness of the quantum well layer is 1.5 to 5 nm, and the thickness of the first conductivity type semiconductor layer or the second conductivity type semiconductor layer is 10 nm to 200 μm. The method according to claim 1,
Wherein the light emitting layer is a multiple quantum well structure in which the quantum well layer and the quantum barrier layer are repeatedly layered. 16. The method of claim 15,
Wherein the planar lattice constant of at least one of the quantum barrier layer and the quantum well layer is gradually increased from the one of the first and second conductivity type semiconductor layers. The method according to claim 1,
Wherein a plane direction lattice constant of at least one of the quantum barrier layer and the quantum well layer varies in a gradient direction in a thickness direction. A first conductive semiconductor layer;
A light emitting layer formed on the first conductive semiconductor layer; And
And a second conductivity type semiconductor layer formed on the light emitting layer,
Wherein the light emitting layer comprises a quantum well layer and a quantum barrier layer,
The energy band gap of the quantum barrier layer and the quantum well layer gradually varies in the thickness direction,
Wherein the quantum barrier layer has a tensile stress with respect to the first conductivity type semiconductor layer or the second conductivity type semiconductor layer, and the quantum well layer has a compressive stress with respect to the first conductivity type semiconductor layer or the second conductivity type semiconductor layer A light emitting device having a stress. 19. The method of claim 18,
Wherein a plane direction lattice constant of the first conductivity type semiconductor layer or the second conductivity type semiconductor layer is larger than a planar direction lattice constant of the quantum barrier layer and smaller than a planar direction lattice constant of the quantum well layer. A package body;
A light emitting device according to any one of claims 1 to 9 and 11 to 19 provided on the package body;
A first electrode and a second electrode provided on the package body and connected to the light emitting element, respectively; And
And a filling material surrounding the light emitting element. delete 18. The light emitting device according to claim 17, wherein the surface direction lattice constant gradually increases in a thickness direction of the quantum well layer from the edge region of the quantum well layer toward the center region. The method of claim 1, wherein at least one of the first conductive semiconductor layer, the second conductive semiconductor layer, the quantum well layer, and the quantum barrier layer comprises indium (In)
Wherein an indium content of each of the quantum barrier layer and the quantum well layer gradually varies in a thickness direction. The method of claim 1, wherein at least one of the first conductive semiconductor layer, the second conductive semiconductor layer, the quantum well layer, and the quantum barrier layer comprises indium (In)
Wherein the quantum barrier layer includes a plurality of quantum barrier layers, the indium contents of the plurality of quantum barrier layers are equal to each other,
Wherein the quantum well layer includes a plurality of quantum well layers and the indium content of the plurality of quantum well layers gradually increases as the distance from one of the first and second conductivity type semiconductor layers increases.

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