KR102237134B1 - Light emitting device and lighting system - Google Patents

Abstract

The light emitting device according to the embodiment includes a light emitting structure including a first conductive type semiconductor layer, an active layer disposed on the first conductive type semiconductor layer, and a second conductive type semiconductor layer disposed on the active layer; And a light extracting structure disposed on the light extracting region of the light emitting structure, wherein the light emitting structure includes a non-polar nitride semiconductor, and the light extracting structure has an uneven structure including a plurality of protrusions, and the plurality of The protrusion is characterized in that it has a shape of at least one of a triangular pillar, a square pillar, or a polygonal pillar.
In another aspect, an embodiment includes a light emitting structure including a first conductivity type semiconductor layer, an active layer disposed on the first conductivity type semiconductor layer, and a second conductivity type semiconductor layer disposed on the active layer; And a light extraction structure disposed on the light extraction region of the light-emitting structure, wherein the light-emitting structure includes a semi-polar nitride semiconductor, and the light extraction structure has an uneven structure including a plurality of protrusions, and the plurality of The protrusion of is characterized in that it has a shape of at least one of a triangular pyramid, a square pyramid, a polygonal pyramid, or a cone.

Description

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

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

Light Emitting Device is a pn junction diode that converts electrical energy into light energy. It can be created as a compound semiconductor such as Group III and Group V on the periodic table. Various colors can be realized by controlling the composition ratio of the compound semiconductor. It is possible.

When the forward voltage is applied, the electrons in the n-layer and the holes in the p-layer are combined to emit energy equivalent to the band gap energy of the conduction band and the balance band. , This energy is mainly emitted in the form of heat or light, and when it is radiated in the form of light, it becomes a light-emitting device.

For example, nitride semiconductors are attracting great interest in the development of optical devices and high-power electronic devices due to their high thermal stability and wide bandgap energy. In particular, a blue light emitting device, a green light emitting device, and an ultraviolet (UV) light emitting device using a nitride semiconductor have been commercialized and widely used.

As the demand for high-efficiency LEDs has recently increased, improvement in light intensity has become an issue. As a way to improve the luminous intensity, the focus is on improving the internal quantum efficiency and light extraction efficiency of the light emitting device. However, in the case of the internal quantum efficiency, among these, the internal quantum efficiency increased almost to the limit value due to optimization of the growth process of the light emitting device. On the other hand, the amount of light generated in the light-emitting device is not emitted outside the light-emitting device and is absorbed in a large amount, so there is still a lot of room for an increase in light extraction efficiency.

This low light extraction efficiency is caused by a large difference in refractive index between the light emitting device and air. According to Snell's law, in order for a photon to be emitted from the inside of the light emitting device to the outside, the photon must be incident at a very small critical angle of refraction or less. Due to this, in the case of the surface of a flat light emitting device, only about 4% of the generated photons can go out. In order to solve this problem, a method of adding various light extraction structures to a light emitting device has been proposed.

The embodiment provides a light-emitting device, a method of manufacturing a light-emitting device, a light-emitting device package, and a lighting system capable of smoothly extracting photons generated in the light-emitting device to the outside by using a simple etching process to improve light extraction efficiency. I want to.

The light emitting device according to the embodiment includes a light emitting structure including a first conductive type semiconductor layer, an active layer disposed on the first conductive type semiconductor layer, and a second conductive type semiconductor layer disposed on the active layer; And a light extraction structure disposed on the light extraction region of the light-emitting structure, wherein the light-emitting structure includes a non-polar nitride semiconductor, and the light extraction structure has an uneven structure including a plurality of protrusions, and the plurality of The protrusion is characterized in that it has a shape of at least one of a triangular pillar, a square pillar, or a polygonal pillar.

In another aspect, an embodiment includes a light emitting structure including a first conductivity type semiconductor layer, an active layer disposed on the first conductivity type semiconductor layer, and a second conductivity type semiconductor layer disposed on the active layer; And a light extraction structure disposed on the light extraction region of the light-emitting structure, wherein the light-emitting structure includes a semi-polar nitride semiconductor, and the light extraction structure has an uneven structure including a plurality of protrusions, and the plurality of The protrusion of is characterized in that it has a shape of at least one of a triangular pyramid, a square pyramid, a polygonal pyramid, or a cone.

In addition, the lighting system according to the embodiment may include a light emitting module including the light emitting device.

According to the embodiment, a light emitting device having an optimal structure capable of increasing luminous intensity, a method of manufacturing a light emitting device, a light emitting device package, and a lighting system can be provided.

Specifically, according to the embodiment, there is an advantage of improving light extraction efficiency by arranging an uneven structure formed in a precise structure in a region where light is to be extracted from the light emitting structure.

In addition, the light emitting structure of the embodiment may include a semi-polar or non-polar nitride semiconductor layer to improve internal quantum efficiency.

In addition, in the embodiment, the light extracting structure disposed on the light emitting structure has the advantage that it can be easily formed through a simple process.

Finally, according to the embodiment, it is possible to provide a light emitting device, a method of manufacturing a light emitting device, a light emitting device package, and a lighting system capable of improving quantum confinement effect, improving luminous efficiency, and improving device reliability.

1 is a cross-sectional view of a light emitting device according to an embodiment.
2 is a perspective view of a protrusion forming a light extraction structure according to the first embodiment, and FIG. 3 is an SEM photograph of a portion of the light extraction structure according to the first embodiment.
4 is a perspective view of a protrusion forming a light extracting structure according to a second embodiment, and FIG. 5 is a SEM photograph of a part of the light extracting structure according to the second embodiment.
6 is a perspective view of a protrusion forming a light extracting structure according to the third embodiment, and FIG. 7 is a SEM photograph of a part of the light extracting structure according to the third embodiment.
8 is a perspective view of a protrusion forming a light extracting structure according to the fourth embodiment, and FIG. 9 is a SEM photograph of a part of the light extracting structure according to the fourth embodiment.
10 to 13 illustrate a process of manufacturing a light emitting device having a light extraction structure according to an embodiment.

In the description of the embodiment, each layer (film), region, pattern, or structure is “on/over” or “below” of the substrate 10, each layer (film), region, pad, or patterns. In the case of being described as being formed in "under)", "on/over" and "under" are "directly" or "indirectly" formed Includes everything. In addition, the criteria for the top/top or bottom of each layer will be described based on the drawings.

1 is a cross-sectional view of a light emitting device according to an embodiment.

Referring to FIG. 1, a light emitting device according to an embodiment includes a first conductivity type semiconductor layer 110, an active layer 120 on the first conductivity type semiconductor layer 110, and an active layer 120 on the first conductivity type semiconductor layer 110. A second conductivity type semiconductor layer 130 and a light extraction structure 140 may be included on the second conductivity type semiconductor layer 130.

First, it may be implemented as a nitride semiconductor including elements such as the first conductivity-type semiconductor layer 110 and groups 3-5 and 2-6. The first conductivity type semiconductor layer 110 may be doped with a first conductivity type dopant. When the first conductivity-type semiconductor layer 110 is an n-type semiconductor layer, the first conductivity-type dopant is an n-type dopant and may include Si, Ge, Sn, Se, and Te, but is not limited thereto.

The first conductivity type semiconductor layer 110 may include _{a semiconductor material having a composition formula of In x} Al _y Ga _1-xy N (0≤x≤1, 0≤y≤1, 0≤x+y≤1). I can. The first conductivity type semiconductor layer 110 may be configured to include any one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, InP. have.

An active layer 120 may be disposed on the first conductivity type semiconductor layer 110.

In the active layer 120, electrons injected through the first conductivity-type semiconductor layer 110 and holes injected through the second conductivity-type semiconductor layer 130 formed thereafter meet each other, so that the active layer 120 (light emitting layer) material is unique. It is a layer that emits photons with energy determined by the energy band of.

In an embodiment, the active layer 120 may be at least one of a single quantum well structure, a multi quantum well structure (MQW), a quantum-wire structure, or a quantum dot structure. have. In addition, the quantum well/quantum wall of the active layer 120 has a pair structure of at least one of InGaN/GaN, InGaN/InGaN, GaN/AlGaN, InAlGaN/GaN, GaAs(InGaAs)/AlGaAs, GaP(InGaP)/AlGaP. However, it is not limited thereto. The quantum well may be a material having a band gap lower than that of the quantum wall. In particular, in an embodiment, in order for the active layer 120 to operate within a high voltage and emit light in an ultraviolet wavelength band, the quantum well/quantum wall may have a GaN/AlGaN pair structure.

A second conductivity type semiconductor layer 130 may be disposed on the active layer 120.

In an embodiment, the second conductivity type semiconductor layer 130 may be implemented as a nitride semiconductor including an element such as Group 3-5, Group 2-6, etc., and may include a second conductivity type dopant. . For example, the second conductivity type semiconductor layer 130 is _{a semiconductor having a composition formula of In x} Al _y Ga _1-xy N (0≤x≤1, 0≤y≤1, 0≤x+y≤1) It may contain substances. When the second conductivity-type semiconductor layer 130 is a p-type semiconductor layer, the second conductivity-type dopant is a p-type dopant and may include Mg, Zn, Ca, Sr, Ba, or the like.

In an embodiment, the first conductivity-type semiconductor layer 110 may be a p-type semiconductor layer, and the second conductivity-type semiconductor layer 130 may be implemented as an n-type semiconductor layer, but is not limited thereto. In addition, a semiconductor, for example, an n-type semiconductor layer (not shown) having a polarity opposite to that of the second conductivity type may be formed on the second conductivity type semiconductor layer 130. Accordingly, the light emitting structure 10 may be implemented in any one of an n-p junction structure, a p-n junction structure, an n-p-n junction structure, and a p-n-p junction structure.

Hereinafter, for convenience of description, the first conductivity-type semiconductor layer 110, the active layer 120, and the second conductivity-type semiconductor layer 130 are collectively referred to as a light emitting structure.

Such a light emitting structure may be formed through epi-growth on the growth substrate 10.

In the case of a general light emitting structure, it may mainly include a polar nitride semiconductor layer grown in the c-axis. However, in the case of a polar nitride semiconductor, a quantum-confined stark effect may occur due to spontaneous and piezoelectric fields that inevitably occur depending on the growth direction of the nitride semiconductor.

Therefore, in order to solve this problem, in the embodiment, the light emitting structure may include a non-polar or semi-polar nitride semiconductor. For example, the light emitting structure may include a non-polar nitride semiconductor layer grown in the a-axis. Alternatively, the light emitting structure may include a semi-polar nitride semiconductor layer grown in the (11-22) axis.

As a method of determining whether the light emitting structure is polar or semi-polar, the non-polar person can know by analyzing the structure formed through the etching process, and it can be possible through optical analysis techniques such as PL and XRD as a non-destructive method.

On the other hand, since the photon generated in the active layer 120 has a large difference in refractive index with the background material outside the light emitting device, the critical angle at which the photon is emitted to the outside has a small value. Accordingly, all photons moving at an angle exceeding the critical angle are not emitted to the outside and are reflected back into the light emitting device, thereby reducing light extraction efficiency.

Particularly, when the region in which photons are emitted from the light emitting device (eg, the top or/and side surfaces of the light emitting structure) is flat, most of the photons are not emitted to the outside and are reflected and absorbed inside the light emitting device. Can occur.

In order to solve this problem, in an embodiment, a light extracting structure 140 may be disposed on the light emitting structure. In detail, a light extraction structure 140 having an uneven shape may be disposed in the light extraction region of the light emitting device. In this case, the light extraction region of the light emitting structure may correspond to the top surface or/and side surfaces of the light emitting structure.

The light extraction structure 140 may include at least one of a photonic crystal structure, a graded-refractive index layer insertion, and a patterned sapphire. However, the above-described configurations are difficult to process, incur excessive cost, and it is difficult to precisely control the uneven shape for light extraction.

In an embodiment, the light extracting structure 140 may have a shape in which a plurality of protrusions 141 are arranged, and the plurality of protrusions 141 may be disposed so as to overlap.

In addition, the plurality of protrusions 141 may have various sizes and may have random shapes.

However, in the embodiment, the shape of the plurality of protrusions 141 may have a certain tendency. That is, although not all of the protrusions 141 have a certain shape, the protrusions 141 may have a tendency of the following shape depending on the crystallinity or etching method of the light emitting structure.

In an embodiment, the plurality of protrusions 141 may be at least one of a triangular pillar, a square pillar, or a polygonal pillar. In another embodiment, the plurality of protrusions 141 may be at least one of a triangular pyramid, a square pyramid, a polygonal pyramid, or a cone. At this time, since the shape of the lower portion of the plurality of protrusions 141 corresponds to the shape of the light extracting structure 140 or the light emitting structure disposed under the protrusions, various shapes of the protrusions 141 described above are the upper shapes of the protrusions 141 It can be understood as explaining the tendency to

2 is a perspective view of a protrusion forming a light extraction structure according to the first embodiment, and FIG. 3 is an SEM photograph of a portion of the light extraction structure according to the first embodiment.

2 to 3, the protrusion 141 forming the light extracting structure 140 according to the first embodiment may be a polygonal column (eg, a triangular column shape). Specifically, the light extracting structure 140 may be a structure arranged to be overlapped so that a plurality of triangular pillars face down.

The shape and size of the light extraction structure 140 of the first embodiment can be precisely controlled by adjusting the pH concentration, the type of the basic solution, and the etching time when wet etching the non-polar nitride semiconductor layer using a basic solution. . That is, in the light extracting structure 140 of the first embodiment, when the light emitting structure includes a non-polar nitride semiconductor, the light-emitting region is basic wet-etched to form an uneven structure in a desired region in a desired shape.

The light extraction structure 140 of the first embodiment can easily form a precise uneven structure in the light extraction region of the light emitting structure, thereby improving light extraction efficiency.

4 is a perspective view of a protrusion forming a light extracting structure according to a second embodiment, and FIG. 5 is a SEM photograph of a part of the light extracting structure according to the second embodiment.

4 to 5, the protrusion 142 constituting the light extracting structure 140 according to the second embodiment is a polygonal pillar (eg, a triangular pillar shape), and a shape around the apex of the polygonal pillar is cut off. Can be Specifically, the light extracting structure 140 may have a structure in which a plurality of polygonal pillars etched around a vertex are arranged so that the side surface thereof is placed down.

As described above, the light extraction structure 140 of the second embodiment may have a structure in which the inclined surface is increased by etching a vertex in the uneven shape of the light extraction structure 140 of the first embodiment. Through this, the light extraction structure 140 according to the second exemplary embodiment further increases roughness, so that the light extraction efficiency may be further improved.

In the light extraction structure 140 of the second embodiment, the non-polar nitride semiconductor layer is wet-etched with a basic solution to form an uneven structure including polygonal pillars, and then wet-etched again with an acidic solution to etch around the vertices of the polygonal pillars. It can be formed by doing.

In the light-emitting structure 140 of the second embodiment, in a light-emitting structure including a non-polar nitride semiconductor layer, basic wet and acidic wet etching is performed on a desired region to easily form a precise uneven structure, thereby improving light extraction efficiency.

6 is a perspective view of a protrusion forming a light extracting structure according to the third embodiment, and FIG. 7 is a SEM photograph of a part of the light extracting structure according to the third embodiment.

6 to 7, the protrusion 143 forming the light extracting structure 140 according to the third embodiment may have a polygonal cone shape.

The shape and size of the light extraction structure 140 of the third embodiment can be controlled by adjusting the pH concentration, the type of the basic solution, the etching time, etc. when wet etching the semi-polar nitride semiconductor layer using a basic solution. That is, the light extraction structure 140 of the third embodiment has an uneven structure in a desired shape by basic wet etching only a region of the surface of the semi-polar nitride semiconductor where light is to be emitted when the light emitting structure includes a semi-polar nitride semiconductor. Can be formed.

Accordingly, the light extraction structure 140 of the third embodiment can improve light extraction efficiency by easily forming a precise uneven structure by basic wet etching of a desired region in a light emitting structure including a semi-polar nitride semiconductor layer.

8 is a perspective view of a protrusion forming a light extracting structure according to the fourth embodiment, and FIG. 9 is a SEM photograph of a part of the light extracting structure according to the fourth embodiment.

8 to 9, the protrusion 141 forming the light extracting structure 140 according to the fourth embodiment has a shape of a polygonal pyramid (eg, a triangular pyramid), and may have a shape in which the periphery of the upper apex of the polygonal pyramid is cut off. have. Specifically, the light extraction structure 140 may have a structure in which a plurality of triangular pyramids smoothly etched around a vertex are arranged.

The light extracting structure 140 of the fourth embodiment may have a structure in which the inclined surface is increased by etching a vertex in the uneven shape of the light extracting structure 140 of the third embodiment. Through this, the light extraction structure 140 according to the third exemplary embodiment further increases the roughness, so that the light extraction efficiency may be further improved.

In the light extraction structure 140 of the fourth embodiment, the semi-polar nitride semiconductor layer is wet-etched with a basic solution to form an uneven structure including a polygonal pyramid, and then wet-etched with an acidic solution to etch the vicinity of the vertex of the polygonal pyramid. Can be formed.

The light extraction structure 140 of the fourth embodiment improves light extraction efficiency by easily forming an uneven structure having high roughness by performing basic wet and acidic wet etching in a desired region in a light emitting structure including a non-polar nitride semiconductor layer. I can make it.

10 to 13 illustrate a process of manufacturing a light emitting device having a light extraction structure according to an embodiment. Hereinafter, a method of manufacturing a light emitting device according to an embodiment will be described with reference to FIGS. 10 to 13.

First, a substrate 10 is prepared as shown in FIG. 10.

In order to form the light extraction structure 140 according to the embodiment, the light emitting structure must be formed of a semi-polar or non-polar nitride semiconductor layer. Accordingly, the substrate 10 may be a material for growing the light emitting structure as a semi-polar or non-polar nitride semiconductor layer. For example, the substrate 10 may be formed of at least one _{of sapphire (Al 2} O ₃ ), SiC, Si, GaAs, GaN, ZnO, GaP, InP, Ge, and Ga ₂ 0 _3. A Patterned Sapphire Substrate (PSS) (not shown) may be formed on the substrate 10, but the embodiment is not limited thereto. Impurities on the surface may be removed by wet cleaning the substrate 10.

Next, a buffer layer 20 may be formed on the substrate 10. The buffer layer 20 may alleviate lattice mismatch between the material of the light emitting structure and the substrate 10, and the material of the buffer layer 20 is a group 3-5 compound semiconductor such as GaN, InN, AlN, InGaN, It may be formed of at least one of AlGaN, InAlGaN, and AlInN.

Thereafter, as shown in FIG. 11, a light emitting structure may be formed on the buffer layer 20.

In order to form the light extracting structure 140 of the first and second embodiments, the light emitting structure can be formed non-polar by growing a nitride semiconductor layer in the a-axis direction.

Alternatively, in order to form the light extraction structure 140 of the third and fourth embodiments, the light emitting structure may be formed semi-polar by growing a nitride semiconductor layer in the (11-22) axis direction.

More specifically, the light emitting structure may be formed of a GaN layer using a method such as chemical vapor deposition (CVD), molecular beam epitaxy (MBE), sputtering, or hydroxide vapor phase epitaxy (HVPE). At this time, in the chamber in which the process is performed, a silane gas (SiH) containing n-type or p-type impurities such as _{trimethyl gallium gas (TMGa), ammonia gas (NH 3} ), nitrogen gas (N _{2 ), and silicon (Si). 4} ) can be formed by injecting.

Thereafter, as shown in FIG. 12, the light-extracting structure 140 may be formed by wet etching a region from which light is to be extracted from the light-emitting structure.

The etching solution used in the embodiment may be potassium hydroxide (KOH, potassium hydroxide), phosphoric acid (H ₃ PO ₄ , Phosphoric acid).

Hereinafter, a method of forming the light extracting structure 140 according to the first to second embodiments will be described. First, the light emitting structure, which is a non-polar nitride semiconductor, may be washed with acetone and IPA solution, and then dried using nitrogen gas. Next, wet etching may be performed by adding a 2M potassium hydroxide solution heated to about 100 degrees to a region in which the light extraction structure 140 is to be formed in the light emitting structure. At this time, the temperature and concentration of the solution can be used in various ways other than the conditions indicated above, and can be adjusted to obtain a desired structure. The light extraction structure 140 having a concave-convex structure including a plurality of polygonal pillars of the first embodiment by performing etching with potassium hydroxide and then washing the light emitting structure with DI water and then drying it with nitrogen gas. Can be formed.

And, as shown in FIG. 13, after performing wet etching with potassium hydroxide, the light extracting structure 140 according to the third embodiment performs wet etching ^{in a phosphoric acid solution at around 100°} C., near the vertex of the triangular pillar. It can be formed by etching. At this time, the concentration of the phosphoric acid solution may be 80 to 90wt%. Even after phosphoric acid etching, a cleaning process using ultrapure water and nitrogen gas can be performed. If the concentration of the phosphoric acid solution is less than 80 wt, the etching becomes weak, and there is a problem that the roughness of the uneven structure is not sufficiently secured. On the other hand, if the concentration of the phosphoric acid solution exceeds 90wt, the light emitting structure may be damaged.

Hereinafter, a method of forming the light extracting structure 140 according to the third to fourth embodiments will be described. First, the light emitting structure, which is a semi-polar nitride semiconductor, may be washed with acetone and IPA solution and then dried using nitrogen gas. Next, wet etching may be performed by adding a 1 to 3M potassium hydroxide solution heated to about 100 degrees to a region in which the light extraction structure 140 is to be formed in the light emitting structure. At this time, the temperature and concentration of the solution may be used in various ways other than the conditions indicated above, and may be adjusted to obtain a desired structure. After performing the etching with potassium hydroxide, the light-emitting structure is washed with DI water and then dried with nitrogen gas, thereby extracting light having an uneven structure including a plurality of triangular pyramids of the second embodiment as shown in FIG. Structure 140 may be formed.

As shown in FIG. 13, the light extraction structure 140 according to the third embodiment is formed by performing wet etching with potassium hydroxide, and then performing wet etching in a phosphoric acid solution at around ^{100° C.} can do. At this time, the concentration of the phosphoric acid solution may be 890 ~ 90wt%. Even after phosphoric acid etching, a cleaning process using ultrapure water and nitrogen gas can be performed.

The light extraction structure 140 according to the embodiment can effectively change the surface of the non-polar or semi-polar nitride semiconductor layer through a simple process without special expensive equipment. In addition, by selectively using a basic etching solution and an acid etching solution, it is possible to implement various shapes of irregularities with high reproducibility. Existing dry etching, which changes the surface of a light emitting structure, causes a lot of damage to the device, but wet etching can be relatively free in these areas.

14 is a view showing a light emitting device package to which a light emitting device according to an embodiment is applied.

Referring to FIG. 14, a light emitting device package according to an embodiment includes a body 205, a first lead electrode 213 and a second lead electrode 214 disposed on the body 205, and the body 205 And a light emitting device provided on and electrically connected to the first lead electrode 213 and the second lead electrode 214, and a molding member 240 surrounding the light emitting device.

The body 205 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.

The first lead electrode 213 and the second lead electrode 214 are electrically separated from each other, and supply power to the light emitting device. In addition, the first lead electrode 213 and the second lead electrode 214 may reflect light generated from the light emitting device to increase light efficiency, and serve to discharge heat generated from the light emitting device to the outside. You can also do it.

The light emitting device may be disposed on the body 205 or may be disposed on the first lead electrode 213 or the second lead electrode 214.

The light emitting device may be electrically connected to the first lead electrode 213 and the second lead electrode 214 by any one of a wire method, a flip chip method, or a die bonding method.

In the embodiment, the light emitting device is mounted on the second lead electrode 214 and may be connected to the first lead electrode 213 and the wire 250, but the embodiment is not limited thereto.

The molding member 240 may surround the light emitting device to protect the light emitting device. In addition, the molding member 240 may include a phosphor 232 to change a wavelength of light emitted from the light emitting device.

A plurality of light emitting devices or light emitting device packages according to the embodiment may be arrayed on the substrate 10, and an optical member such as a lens, a light guide plate, a prism sheet, and a diffusion sheet may be disposed on the optical path of the light emitting device package. . The light emitting device package, the substrate 10, and the optical member may function as a light unit. The light unit may be implemented in a top view or a side view type, and may be provided to a display device such as a portable terminal and a notebook computer, or may be variously applied to a lighting device and an indication device. Another embodiment may be implemented with a lighting device including the light emitting device or the light emitting device package described in the above-described embodiments. For example, the lighting device may include a lamp, a street light, an electric sign, and a headlamp.

Features, structures, effects, and the like described in the embodiments above are included in at least one embodiment, and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects, and the like illustrated in each embodiment may be combined or modified for other embodiments by a person having ordinary knowledge in the field to which the embodiments belong. Therefore, contents related to such combinations and modifications should be construed as being included in the scope of the embodiments.

Although the embodiments have been described above, these are only examples and are not intended to limit the embodiments, and those of ordinary skill in the field to which the embodiments belong are not departing from the essential characteristics of the present embodiment. It will be seen that branch transformation and application are possible. For example, each component specifically shown in the embodiment can be modified and implemented. And differences related to these modifications and applications should be construed as being included in the scope of the embodiments set in the appended claims.

Claims (7)

A light emitting structure including a first conductivity type semiconductor layer, an active layer disposed on the first conductivity type semiconductor layer, and a second conductivity type semiconductor layer disposed on the active layer; And
Including; a light extraction structure disposed on the light extraction region of the light emitting structure,
The light emitting structure includes a non-polar or semi-polar nitride semiconductor,
The light extraction structure is disposed on an upper surface or on an upper surface and a side surface of the light emitting structure,
The light extraction structure has an uneven structure including a plurality of protrusions,
The plurality of protrusions of the uneven structure extend in a first direction,
The plurality of protrusions have a shape of at least one of a triangular pillar, a square pillar, or a polygonal pillar with a cut around a vertex,
The first surface exposed by being cut around the vertex in the plurality of protrusions is disposed to be inclined with respect to the first direction,
The vertical distance between the lower surface of the protrusion facing the active layer and the first surface changes toward the first direction,
A light emitting device having an acute angle of inclination between the lower surface of the protrusion and the first surface. delete delete delete delete delete delete

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