KR20150142412A - Light emitting device - Google Patents

Abstract

According to an embodiment, a light emitting device includes: a light emitting structure including a first conductive semiconductor layer, an active layer placed under the first conductive semiconductor layer, and a second conductive semiconductor layer placed under the active layer; a window layer placed under the light emitting structure; a reflecting layer placed under the window layer; and a first electrode placed on the light emitting structure, and electrically connected to the first conductive semiconductor layer. The first conductive semiconductor layer includes the composition of (AlxGa1-x)yIn1-yP(0.4<x<=0.8, 0<y<=1). The first electrode includes a main electrode and a surrounding electrode extended from the main electrode to the surroundings and the main electrode of the first electrode has a circular shape having a diameter of 120 micrometers or less.

Description

[0001] LIGHT EMITTING DEVICE [0002]

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

Light emitting diodes (LEDs) are widely used as light emitting devices. Light emitting diodes convert electrical signals into light, such as infrared, visible, and ultraviolet, using the properties of compound semiconductors.

As the light efficiency of a light emitting device is increased, a light emitting device is applied to various fields including a display device and a lighting device.

Embodiments provide a light emitting device, a light emitting device package, and a light unit capable of improving light flux and lowering an operating voltage by selecting an electrode shape according to a composition of a light emitting structure.

A light emitting device according to an embodiment includes a light emitting structure including a first conductive semiconductor layer, an active layer disposed under the first conductive semiconductor layer, and a second conductive semiconductor layer disposed under the active layer; A window layer disposed below the light emitting structure; A reflective layer disposed below the window layer; A first electrode disposed on the light emitting structure and electrically connected to the first conductive semiconductor layer; Wherein the first conductivity type semiconductor layer includes a composition of (Al _x Ga _{1 -x} ) _y In _{1 -y} P (0.4 <x? 0.8, 0 <y? 1) And a peripheral electrode extending from the main electrode to the periphery, wherein the main electrode of the first electrode is provided in a circular shape having a diameter of 120 micrometers or less.

A light emitting device according to an embodiment includes a light emitting structure including a first conductive semiconductor layer, an active layer disposed under the first conductive semiconductor layer, and a second conductive semiconductor layer disposed under the active layer; A window layer disposed below the light emitting structure; A reflective layer disposed below the window layer; A first electrode disposed on the light emitting structure and electrically connected to the first conductive semiconductor layer; Wherein the first conductivity type semiconductor layer comprises a composition of (Al _x Ga _{1 -x} ) _y In _{1 -y} P (0.1 _x 0.4, 0 < y 1) And is provided in a circular shape having a diameter of not more than a micrometer.

The light emitting device, the light emitting device package, and the light unit according to the embodiments have advantages that the shape of the electrode can be selected according to the composition of the light emitting structure to improve the light flux and reduce the operating voltage.

1 is a view illustrating a light emitting device according to an embodiment.
2 is a view showing an example of the arrangement of the first electrode and the ohmic contact region applied to the light emitting device according to the embodiment.
FIG. 3 is a graph illustrating a change in operation voltage according to Al compositional change included in a light emitting structure in a light emitting device according to an embodiment.
4 is a graph illustrating a change in luminous flux according to Al compositional change included in a light emitting structure of a light emitting device according to an embodiment.
5 to 8 are views showing a method of manufacturing a light emitting device according to an embodiment.
9 and 10 are views showing another example of the light emitting device according to the embodiment.
11 is a view illustrating a light emitting device package according to an embodiment.
12 is a view showing a display device according to an embodiment.
13 is a view showing another example of the display device according to the embodiment.
14 is a view showing a lighting apparatus according to an embodiment.

In the description of the embodiments, it is to be understood that each layer (film), region, pattern or structure may be referred to as being "on" or "under" a substrate, each layer It is to be understood that the terms " on "and " under" include both " directly "or" indirectly " do. In addition, the criteria for the top / bottom or bottom / bottom of each layer are described with reference to the drawings.

Hereinafter, a light emitting device, a light emitting device package, a light unit, and a method of manufacturing a light emitting device according to embodiments will be described in detail with reference to the accompanying drawings.

1 is a view illustrating a light emitting device according to an embodiment.

The light emitting device according to the embodiment may include a light emitting structure 10, a window layer 15, a reflective layer 30, and a first electrode 60, as shown in FIG.

The light emitting structure 10 may include a first conductivity type semiconductor layer 11, an active layer 12, and a second conductivity type semiconductor layer 13. The active layer 12 may be disposed between the first conductive semiconductor layer 11 and the second conductive semiconductor layer 13. The active layer 12 may be disposed under the first conductive semiconductor layer 11 and the second conductive semiconductor layer 13 may be disposed under the active layer 12.

For example, the first conductivity type semiconductor layer 11 is formed of an n-type semiconductor layer doped with an n-type dopant as a first conductivity type dopant, and the second conductivity type semiconductor layer 13 is formed of a second conductivity type dopant Type semiconductor layer to which a p-type dopant is added. The first conductivity type semiconductor layer 11 may be formed of a p-type semiconductor layer, and the second conductivity type semiconductor layer 13 may be formed of an n-type semiconductor layer.

The first conductive semiconductor layer 11 may include, for example, an n-type semiconductor layer. The first conductive semiconductor layer 11 may be formed of a compound semiconductor. The first conductive semiconductor layer 11 may be formed of, for example, a Group II-VI compound semiconductor or a Group III-V compound semiconductor.

For example, the first conductive type semiconductor layer 11 (Al _x Ga _{1 -x) y} In _{1 -} can be implemented in a semiconductor material having a composition formula _y P (0≤x≤1, 0≤y≤1) have. In the composition formula of the first conductivity type semiconductor layer 11, y has a value of 0.5 and x may have a value of 0.5 to 0.8. The first conductive semiconductor layer 11 may be selected from AlGaInP, AlInP, GaP, GaInP, and the like, and may be doped with an n-type dopant such as Si, Ge, Sn, Se or Te.

The active layer 12 is formed in such a manner that electrons (or holes) injected through the first conductive type semiconductor layer 11 and holes (or electrons) injected through the second conductive type semiconductor layer 13 meet with each other, And is a layer that emits light due to a band gap difference of an energy band according to a material of the active layer 12. [ The active layer 12 may be formed of any one of a single well structure, a multi-well structure, a quantum dot structure and a quantum wire structure, but is not limited thereto.

The active layer 12 may be formed of a compound semiconductor. The active layer 12 may be formed of, for example, a Group II-VI or III-V compound semiconductor. The active layer 12 is by way of example _{(Al x Ga 1 -x) y} In 1 - can be implemented in a semiconductor material having a composition formula _y P (0≤x≤1, 0≤y≤1). The active layer 12 may be selected from, for example, AlGaInP, AlInP, GaP, GaInP, and the like. When the active layer 12 is implemented as a multi-well structure, the active layer 12 may be formed by stacking a plurality of well layers and a plurality of barrier layers.

The second conductive semiconductor layer 13 may be formed of, for example, a p-type semiconductor layer. The second conductive semiconductor layer 13 may be formed of a compound semiconductor. The second conductive semiconductor layer 13 may be formed of, for example, a Group II-VI compound semiconductor or a Group III-V compound semiconductor.

For example, the second conductive type semiconductor layer 13 _{(Al x Ga 1 -x) y} In 1 - can be implemented in a semiconductor material having a composition formula _y P (0≤x≤1, 0≤y≤1) have. The second conductive semiconductor layer 13 may be selected from AlGaInP, AlInP, GaP, GaInP, and the like, and may be doped with a p-type dopant such as Mg, Zn, Ca, Sr,

For example, the light emitting structure 10 may include at least two or more elements selected from aluminum (Al), gallium (Ga), indium (In), and phosphorous (P)

Meanwhile, the first conductive semiconductor layer 11 may include a p-type semiconductor layer and the second conductive semiconductor layer 13 may include an n-type semiconductor layer. Also, a semiconductor layer including an n-type or p-type semiconductor layer may be further formed under the second conductivity type semiconductor layer 13. Accordingly, the light emitting structure 10 may have at least one of np, pn, npn, and pnp junction structures. The doping concentration of impurities in the first conductivity type semiconductor layer 11 and the second conductivity type semiconductor layer 13 may be uniform or non-uniform. That is, the structure of the light emitting structure 10 may be variously formed, but the present invention is not limited thereto.

The light emitting device according to the embodiment may include the window layer 15. The window layer 15 _{(Al x Ga 1 -x) y} In 1 - can be implemented in a semiconductor material having a composition formula _y P (0≤x≤1, 0≤y≤1). The window layer 15 may be selected from, for example, AlGaInP, AlInP, GaP, GaInP, and the like. The window layer 15 may be disposed below the light emitting structure 10. The window layer 15 may be disposed under the second conductive semiconductor layer 13. The window layer 15 may contain impurities. The window layer 15 may include an impurity which is the same as the polarity of the impurity contained in the second conductive semiconductor layer 13. For example, the window layer 15 may include the same impurity as the impurity contained in the second conductivity type semiconductor layer 13. The window layer 15 may provide a current spreading effect.

The light emitting device according to the embodiment may include an ODR (Omni Directional Reflector) layer 21, an ohmic contact layer 23, and a reflective layer 30.

The ODR layer 21 may function to reflect light incident from the upper direction toward the upper direction. The ODR layer 21 may be formed to have a lower refractive index than the light emitting structure 10, for example. The ODR layer 21 is selected to have a low refractive index which is greatly different from the refractive index of the material forming the light emitting structure 10, thereby providing a reflective function. The ODR layer 21 may be disposed in contact with the window layer 15.

The ODR layer 21 may include an oxide or a nitride. The ODR layer 21 may be formed of, for example, SiO ₂ , SiN _x , Indium-Tin-Oxide (IZO), Indium-Zinc-Oxide (AZO), Aluminum- ), IZTO (indium-zinc-tin-oxide), IAZO (indium-aluminum-zinc-oxide), GZO (gallium-zinc-oxide), IGZO (indium- Tin-Oxide), and Aluminum-Zinc-Oxide (AZO).

The ohmic contact layer 23 may be disposed under the window layer 15. The ohmic contact layer 23 may be formed to be in ohmic contact with the window layer 15. The ohmic contact layer 23 may include a region in ohmic contact with the window layer 15. The ohmic contact layer 23 may include a plurality of ohmic contact regions which are spaced apart from each other and which are in ohmic contact with the window layer 15. For example, the ohmic contact layer 23 may include a plurality of dot-shaped ohmic contact regions spaced apart from each other.

The ohmic contact layer 23 may be electrically connected to the light emitting structure 10. The ohmic contact layer 23 may be electrically connected to the second conductive semiconductor layer 13. The ohmic contact layer 23 may be disposed through the ODR layer 21. For example, the ohmic contact region of the ohmic contact layer 23 may have a circular or oval top surface. The ohmic contact layer 23 may include at least one selected from the group consisting of Au, Au / AuBe / Au, AuZn, ITO, AuBe, and GeAu.

The reflective layer 30 may be disposed under the window layer 15. The reflective layer 30 may be disposed under the ohmic contact layer 23. [ The reflective layer 30 may be disposed under the ODR layer 21. The reflective layer 30 may function to reflect the light incident from the upper direction toward the upper direction. The reflective layer 30 may include a metal layer. The reflective layer 30 may include at least one selected from the group consisting of Ag, Au, and Al.

The light emitting device according to the embodiment may include a bonding layer 40 and a support substrate 50. The bonding layer 40 may function to attach the reflective layer 30 and the support substrate 50 to each other.

 The bonding layer 40 may be formed of a material such as Sn, AuSn, Pd, Al, Ti, Au, Ni, Cr, Ga, In, Bi, Cu, Ag, Nb, Ta, Ti / Au / And the like. The supporting substrate 50 may be a semiconductor substrate (for example, Si, Ge, GaN, GaAs, ZnO, SiC, or the like) into which Ti, Cr, Ni, Al, Pt, Au, W, Cu, SiGe, and the like).

The light emitting device according to the embodiment may include a first electrode 60, an electrode pad 70, and a protective layer 80 disposed on the light emitting structure 10.

The first electrode 60 may be electrically connected to the first conductive semiconductor layer 11. The first electrode 60 may be disposed in contact with the first conductive semiconductor layer 11. The first electrode 60 may be disposed in ohmic contact with the first conductive semiconductor layer 11. The first electrode 60 may include a region in ohmic contact with the light emitting structure 10. The first electrode 60 may include a region in ohmic contact with the first conductive semiconductor layer 11. The first electrode 60 may include at least one selected from Ge, Zn, Mg, Ca, Au, Ni, AuGe, and AuGe / Ni / Au.

The light emitting device according to the embodiment may further include a high-concentration impurity semiconductor layer between the first electrode 60 and the first conductivity type semiconductor layer 11. For example, the high concentration impurity semiconductor layer may be formed of a GaAs layer. The heavily doped impurity semiconductor layer may include an impurity having the same polarity as that of the first conductivity type semiconductor layer 11. The heavily doped impurity semiconductor layer may include impurities at a higher concentration than the first conductivity type semiconductor layer 11.

The electrode pad 70 may be electrically connected to the first electrode 60. The electrode pad 70 may be disposed on the first electrode 60. The electrode pad 70 may be disposed in contact with the first electrode 60. The electrode pad 70 may be connected to an external power source to provide power to the light emitting structure 10. The electrode pad 70 may be formed of a metal such as Cr, V, W, Ti, Zn, Ni, Cu, Al, Au, Mo, Ti / Au / Ti / Pt / Au, / Ni / Cu / Ni / Au, and the like.

According to an embodiment, the protective layer 80 may be disposed on the light emitting structure 10. The protective layer 80 may be disposed around the light emitting structure 10. The protective layer 80 may be disposed on a side surface of the light emitting structure 10. The protective layer 80 may be disposed around the window layer 15. A portion of the protective layer 80 may be disposed on a portion of the window layer 15.

The protective layer 80 may include at least one of oxide and nitride. The protective layer 80 may include at least one selected from the group consisting of SiO ₂ , Si _x O _y , Si ₃ N ₄ , Si _x N _y , SiO _x N _y , Al ₂ O ₃ , TiO ₂ , .

2 is a plan view showing an example of the arrangement of the first electrode 60 and the ohmic contact region applied to the light emitting device according to the embodiment.

The first electrode 60 according to the embodiment may be disposed on the light emitting structure 10. The first electrode 60 may include a main electrode 61 and a peripheral electrode 63. For example, the main electrode 61 may be disposed at a central region of the upper surface of the light emitting structure 10, and the peripheral electrode 63 may extend from the main electrode 61 to the periphery. The peripheral electrode 63 may be branched from the main electrode 61 and extend outwardly. For example, the width of the peripheral electrode 63 may be 4 to 5 micrometers. The main electrode 61 may include a circular or polygonal upper surface.

The first electrode 60 may be electrically connected to the first conductive semiconductor layer 11. The main electrode 61 may be electrically connected to the first conductive semiconductor layer 11. The peripheral electrode 63 may be electrically connected to the first conductivity type semiconductor layer 11.

According to the embodiment, the electrode pad 70 may be disposed at a position corresponding to the main electrode 61. The shape of the electrode pad 70 may include a circular or polygonal upper surface. The area of the electrode pad 70 may be equal to or smaller than the area of the main electrode 61, for example.

The electrode pad 70 may be electrically connected to the first electrode 60. The electrode pad 70 may be electrically connected to the main electrode 61. The electrode pad 70 may be electrically connected to the peripheral electrode 63. According to the embodiment, the electrode pad 70 may be disposed on the main electrode 61. The electrode pad 70 may be disposed in contact with the main electrode 61.

According to an embodiment, the protective layer 80 may be disposed on the light emitting structure 10. The passivation layer 80 may be disposed on the first conductive semiconductor layer 11. The first conductive semiconductor layer 11 may include a light extracting structure provided on an upper surface thereof. The light extracting structure may be referred to as a concave-convex structure. The light extracting structure may also be referred to as roughness. The passivation layer 80 may include a light extracting structure corresponding to the light extracting structure provided in the first conductivity type semiconductor layer 11.

According to the embodiment, the arrangement of the main electrode 61 and the peripheral electrode 63 can be variously modified. The arrangement of the pad electrode 70 may be variously modified corresponding to the arrangement of the main electrode 61 and the peripheral electrode 63.

1, the support substrate 50 may be formed of a conductive material, and a power source may be connected to the light emitting structure 10 by an external power source connected to the support substrate 50, . Power may be applied to the second conductivity type semiconductor layer 13 through the support substrate 50.

A second electrode electrically connected to the second conductivity type semiconductor layer 13 may be formed on the ohmic contact layer 23, the reflective layer 30, the bonding layer 40, 50).

3 and 4, it can be seen that the operating voltage and the light flux are changed according to the Al composition included in the light emitting structure 10 according to the embodiment. In addition, according to the embodiment, it was confirmed that the operating voltage and the luminous flux change tend to be different according to the shape of the first electrode 60 according to the Al composition.

FIG. 3 is a graph showing an operation voltage change according to Al compositional change included in the light emitting structure of the light emitting device according to the embodiment. FIG. 4 is a graph showing the change in the Al composition of the light emitting device according to the embodiment. Fig. 3 and 4 denote the case where the first electrode 60 includes both the main electrode 61 and the peripheral electrode 63 as shown in FIG. 2 , and 'circle' indicates that the first electrode 60 includes only the main electrode 61. In addition, the peripheral electrode 63 refers to an extension wiring branched from the main electrode 61. The peripheral electrode 63 may have a shape shown in FIG. 2 and extend radially or linearly from the main electrode 61 May be provided.

 Changes in the operating voltage and flux of light shown in FIGS. 3 and 4 can be summarized as shown in Table 1 below.

characteristic Electrode shape  Al composition 30% 40% 50% 60% 70% Operating voltage
(V) circle 2.30 2.40 2.62 2.86 3.22 star 2.30 2.32 2.38 2.45 2.65 Beam
(lm) circle 1.10 1.00 0.93 0.82 0.72 star 1.00 0.97 1.07 1.03 0.94

That is, the operating voltage tends to increase as the Al composition increases, and it can be seen that the light flux tends to decrease as the Al composition increases. However, when the Al composition is larger than about 40%, it can be seen that the luminous flux in the case of forming 'star' with respect to 'circle' shows a larger value and the operating voltage shows a smaller value.

With reference to this tendency, the light emitting device according to the embodiment can provide the shape of the first electrode 60 according to the Al composition as follows. Here, the Al composition represents the compositional change of Al contained in the first conductivity type semiconductor layer 11. In addition, the lower surface area of the light emitting structure 10 may be 0.1 mm 2 or less. For example, the lower surface of the light emitting structure 10 may be provided with a width of 300 mu m both in the lateral and vertical directions.

According to the embodiment, when the first conductivity type semiconductor layer 11 includes a composition of (Al _x Ga _{1 -x} ) _y In _{1 -y} P (0.4 <x ≦ 0.8, 0 <y ≦ 1) 2, the first electrode 60 may include the main electrode 61 and the peripheral electrode 63 extending from the main electrode 61 to the periphery. For example, the main electrode 61 of the first electrode 60 may be provided in a circular shape having a diameter of 120 micrometers or less. The main electrode 61 may be provided to have a diameter of 80 micrometers to 120 micrometers.

Meanwhile, as shown in FIG. 2, the ohmic contact layer 23 may include a plurality of ohmic contact regions having a dot shape. For example, the width of the point shape of the ohmic contact layer 23 may be selected from 5 micrometers to 15 micrometers. The ohmic contact region of the point shape of the ohmic contact layer 23 may be provided with 20 to 40 ohmic contact regions.

According to the embodiment, the first electrode 60 and the plurality of ohmic contact regions may be arranged so as not to overlap each other in the vertical direction. Accordingly, the current applied to the light emitting structure 10 can be diffused and flowed, and the luminous efficiency can be improved.

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

5, an etch stop layer 7, a first conductivity type semiconductor layer 11, an active layer 12, a second conductive type semiconductor layer 11, and a second conductive type semiconductor layer 11 are sequentially formed on a substrate 5, The semiconductor layer 13 and the window layer 15 may be formed. The first conductive semiconductor layer 11, the active layer 12 and the second conductive semiconductor layer 13 may be referred to as a light emitting structure 10.

The substrate 5 may be formed of at least one of, for example, a sapphire substrate (Al ₂ O ₃ ), SiC, GaAs, GaN, ZnO, Si, GaP, InP and Ge. A buffer layer may be further formed between the substrate 5 and the etch stop layer 7.

The etching stop layer 7 is an example _{(Al x Ga 1 -x) y} In 1 - can be implemented in a semiconductor material having a composition formula _y P (0≤x≤1, 0≤y≤1). The function of the etch stop layer 7 will be described later.

According to the embodiment, the first conductivity type semiconductor layer 11 is formed of an n-type semiconductor layer doped with an n-type dopant as a first conductivity type dopant, and the second conductivity type semiconductor layer 13 is formed of an n- And a p-type semiconductor layer doped with a p-type dopant as a dopant. The first conductivity type semiconductor layer 11 may be formed of a p-type semiconductor layer, and the second conductivity type semiconductor layer 13 may be formed of an n-type semiconductor layer.

The first conductive semiconductor layer 11 may include, for example, an n-type semiconductor layer. The first conductive semiconductor layer 11 may be formed of a compound semiconductor. The first conductive semiconductor layer 11 may be formed of, for example, a Group II-VI compound semiconductor or a Group III-V compound semiconductor.

For example, the first conductive type semiconductor layer 11 (Al _x Ga _{1 -x) y} In _{1 -} can be implemented in a semiconductor material having a composition formula _y P (0≤x≤1, 0≤y≤1) have. In the composition formula of the first conductivity type semiconductor layer 11, y has a value of 0.5 and x may have a value of 0.5 to 0.8. The first conductive semiconductor layer 11 may be selected from AlGaInP, AlInP, GaP, GaInP, and the like, and may be doped with an n-type dopant such as Si, Ge, Sn, Se or Te.

The active layer 12 is formed in such a manner that electrons (or holes) injected through the first conductive type semiconductor layer 11 and holes (or electrons) injected through the second conductive type semiconductor layer 13 meet with each other, And is a layer that emits light due to a band gap difference of an energy band according to a material of the active layer 12. [ The active layer 12 may be formed of any one of a single well structure, a multi-well structure, a quantum dot structure and a quantum wire structure, but is not limited thereto.

The active layer 12 may be formed of a compound semiconductor. The active layer 12 may be formed of, for example, a Group II-VI or III-V compound semiconductor. The active layer 12 is by way of example _{(Al x Ga 1 -x) y} In 1 - can be implemented in a semiconductor material having a composition formula _y P (0≤x≤1, 0≤y≤1). The active layer 12 may be selected from, for example, AlGaInP, AlInP, GaP, GaInP, and the like. When the active layer 12 is implemented as a multi-well structure, the active layer 12 may be formed by stacking a plurality of well layers and a plurality of barrier layers.

The second conductive semiconductor layer 13 may be formed of, for example, a p-type semiconductor layer. The second conductive semiconductor layer 13 may be formed of a compound semiconductor. The second conductive semiconductor layer 13 may be formed of, for example, a Group II-VI compound semiconductor or a Group III-V compound semiconductor.

For example, the second conductive type semiconductor layer 13 _{(Al x Ga 1 -x) y} In 1 - can be implemented in a semiconductor material having a composition formula _y P (0≤x≤1, 0≤y≤1) have. The second conductive semiconductor layer 13 may be selected from AlGaInP, AlInP, GaP, GaInP, and the like, and may be doped with a p-type dopant such as Mg, Zn, Ca, Sr,

For example, the light emitting structure 10 may include at least two or more elements selected from aluminum (Al), gallium (Ga), indium (In), and phosphorous (P)

The window layer 15 _{(Al x Ga 1 -x) y} In 1 - can be implemented in a semiconductor material having a composition formula _y P (0≤x≤1, 0≤y≤1). The window layer 15 may be selected from, for example, AlGaInP, AlInP, GaP, GaInP, and the like. The window layer 15 may provide a current spreading effect when the light emitting device is driven.

Next, an ODR layer 21, an ohmic contact layer 23, and a reflective layer 30 may be formed on the window layer 15, as shown in FIG.

The ODR layer 21 may reflect the incident light again. The ODR layer 21 may be formed to have a lower refractive index than the light emitting structure 10, for example. The ODR layer 21 is selected to have a low refractive index which is greatly different from the refractive index of the material forming the light emitting structure 10, thereby providing a reflective function. The ODR layer 21 may be disposed in contact with the window layer 15.

The ODR layer 21 may include an oxide or a nitride. The ODR layer _{21, SiO 2, SiNx, ITO (} Indium-Tin-Oxide), IZO (Indium-Zinc-Oxide), AZO (Aluminum-Zinc-Oxide), ATO (Antimony-Tin-Oxide) as an example IZTO (Indium-Zinc-Tin-Oxide), IZO (Indium-Aluminum-Zinc-Oxide), GZO (Gallium-Zinc-Oxide), IGZO -Oxide, and AZO (Aluminum-Zinc-Oxide).

 The ohmic contact layer 23 may be formed to be in ohmic contact with the window layer 15. The ohmic contact layer 23 may include a region in ohmic contact with the window layer 15. The ohmic contact layer 23 may be electrically connected to the light emitting structure 10. The ohmic contact layer 23 may be disposed through the ODR layer 21. For example, the ohmic contact layer 23 may be implemented with a top surface of a circular or oval shape. The ohmic contact layer 23 may include at least one selected from the group consisting of Au, Au / AuBe / Au, AuZn, ITO, AuBe, and GeAu.

The reflective layer 30 may be disposed on the ohmic contact layer 23. The reflective layer 30 may be disposed on the ODR layer 21. The reflective layer 30 may reflect the incident light again. The reflective layer 30 may include at least one selected from the group consisting of Ag, Au, and Al.

7, a bonding layer 40 and a support substrate 50 may be provided on the reflective layer 30. In this case,

The bonding layer 40 may function to attach the reflective layer 30 and the support substrate 50 to each other. The bonding layer 40 may be formed of a material such as Sn, AuSn, Pd, Al, Ti, Au, Ni, Cr, Ga, In, Bi, Cu, Ag, Nb, Ta, Ti / Au / And the like. The supporting substrate 50 may be a semiconductor substrate (for example, Si, Ge, GaN, GaAs, ZnO, SiC, or the like) into which Ti, Cr, Ni, Al, Pt, Au, W, Cu, SiGe, and the like).

Next, the substrate 5 is removed from the etch stop layer 7. As an example, the substrate 5 may be removed by an etching process. If the substrate 5 is implemented as GaAs, the substrate 5 may be removed by a wet etch process, and the etch stop layer 7 is not etched to etch only the substrate 5 The function of the stop layer can be performed. The etch stop layer 7 may be separated from the light emitting structure 10 through a separate removal process. For example, the etch stop layer 7 may be removed through a separate etch process. The etch stop layer 7 may be formed of a semiconductor material having a composition formula of (Al _x Ga _{1 -x} ) _y In _{1 -y} P (0? _X ? 1, 0? _Y ?

8, a first electrode 60 may be formed on the light emitting structure 10, and a light extracting structure may be formed on the first conductive semiconductor layer 11. Referring to FIG. Next, isolation etching may be performed to etch the side surfaces of the light emitting structure 10. A protective layer 80 and an electrode pad 70 may be formed on the light emitting structure 10.

The first electrode 60 according to the embodiment may be disposed on the light emitting structure 10. The first electrode 60 may include a main electrode 61 and a peripheral electrode 63. 2 and 8, the main electrode 61 may be disposed in a central region of the upper surface of the light emitting structure 10, and the peripheral electrode 63 may be disposed on the main electrode 61 And extend in the outward direction. For example, the width of the peripheral electrode 63 may be 4 to 5 micrometers. The main electrode 61 may include a circular or polygonal upper surface.

The first electrode 60 may be electrically connected to the first conductive semiconductor layer 11. The main electrode 61 may be electrically connected to the first conductive semiconductor layer 11. The peripheral electrode 63 may be electrically connected to the first conductivity type semiconductor layer 11.

According to the embodiment, the electrode pad 70 may be disposed at a position corresponding to the main electrode 61. The shape of the electrode pad 70 may include a circular or polygonal upper surface.

The electrode pad 70 may be electrically connected to the first electrode 60. The electrode pad 70 may be electrically connected to the main electrode 61. The electrode pad 70 may be electrically connected to the peripheral electrode 63. According to the embodiment, the electrode pad 70 may be disposed on the main electrode 61. The electrode pad 70 may be disposed in contact with the main electrode 61.

According to an embodiment, the protective layer 80 may be disposed on the light emitting structure 10. The passivation layer 80 may be disposed on the first conductive semiconductor layer 11. The first conductive semiconductor layer 11 may include a light extracting structure provided on an upper surface thereof. The light extracting structure may be referred to as a concave-convex structure. The light extracting structure may also be referred to as roughness. The passivation layer 80 may include a light extracting structure corresponding to the light extracting structure provided in the first conductivity type semiconductor layer 11.

According to the embodiment, the arrangement of the main electrode 61 and the peripheral electrode 63 can be variously modified. The arrangement of the pad electrode 70 may be variously modified corresponding to the arrangement of the main electrode 61 and the peripheral electrode 63.

9 and 10 are views showing another example of the light emitting device according to the embodiment. 9 and 10, in the description of the light emitting device according to the embodiment, the parts described with reference to FIGS. 1 to 8 may be omitted or briefly described.

The light emitting device according to the embodiment may include a light emitting structure 10, a window layer 15, a reflective layer 30, and a first electrode 60, as shown in FIGS.

The light emitting structure 10 may include a first conductivity type semiconductor layer 11, an active layer 12, and a second conductivity type semiconductor layer 13. The active layer 12 may be disposed between the first conductive semiconductor layer 11 and the second conductive semiconductor layer 13. The active layer 12 may be disposed under the first conductive semiconductor layer 11 and the second conductive semiconductor layer 13 may be disposed under the active layer 12.

The light emitting device according to the embodiment may include the window layer 15. The window layer 15 _{(Al x Ga 1 -x) y} In 1 - can be implemented in a semiconductor material having a composition formula _y P (0≤x≤1, 0≤y≤1). The window layer 15 may be selected from, for example, AlGaInP, AlInP, GaP, GaInP, and the like. The window layer 15 may be disposed below the light emitting structure 10. The window layer 15 may be disposed under the second conductive semiconductor layer 13. The window layer 15 may contain impurities. The window layer 15 may include an impurity which is the same as the polarity of the impurity contained in the second conductive semiconductor layer 13. For example, the window layer 15 may include the same impurity as the impurity contained in the second conductivity type semiconductor layer 13. The window layer 15 may provide a current spreading effect.

The light emitting device according to the embodiment may include an ODR (Omni Directional Reflector) layer 21, an ohmic contact layer 23, and a reflective layer 30.

The ODR layer 21 may function to reflect light incident from the upper direction toward the upper direction. The ODR layer 21 may be formed to have a lower refractive index than the light emitting structure 10, for example. The ODR layer 21 is selected to have a low refractive index which is greatly different from the refractive index of the material forming the light emitting structure 10, thereby providing a reflective function. The ODR layer 21 may be disposed in contact with the window layer 15.

The ohmic contact layer 23 may be disposed under the window layer 15. The ohmic contact layer 23 may be formed to be in ohmic contact with the window layer 15. The ohmic contact layer 23 may include a region in ohmic contact with the window layer 15. The ohmic contact layer 23 may include a plurality of ohmic contact regions which are spaced apart from each other and which are in ohmic contact with the window layer 15. For example, the ohmic contact layer 23 may include a plurality of dot-shaped ohmic contact regions spaced apart from each other.

The ohmic contact layer 23 may be electrically connected to the light emitting structure 10. The ohmic contact layer 23 may be electrically connected to the second conductive semiconductor layer 13. The ohmic contact layer 23 may be disposed through the ODR layer 21. For example, the ohmic contact region of the ohmic contact layer 23 may have a circular or oval top surface.

The reflective layer 30 may be disposed under the window layer 15. The reflective layer 30 may be disposed under the ohmic contact layer 23. [ The reflective layer 30 may be disposed under the ODR layer 21. The reflective layer 30 may function to reflect the light incident from the upper direction toward the upper direction. The reflective layer 30 may include a metal layer. The reflective layer 30 may include at least one selected from the group consisting of Ag, Au, and Al.

The light emitting device according to the embodiment may include a bonding layer 40 and a support substrate 50. The bonding layer 40 may function to attach the reflective layer 30 and the support substrate 50 to each other.

The light emitting device according to the embodiment may include a first electrode 60, an electrode pad 70, and a protective layer 80 disposed on the light emitting structure 10.

The first electrode 60 may be electrically connected to the first conductive semiconductor layer 11. The first electrode 60 may be disposed in contact with the first conductive semiconductor layer 11. The first electrode 60 may be disposed in ohmic contact with the first conductive semiconductor layer 11. The first electrode 60 may include a region in ohmic contact with the light emitting structure 10. The first electrode 60 may include a region in ohmic contact with the first conductive semiconductor layer 11. The first electrode 60 may include at least one selected from Ge, Zn, Mg, Ca, Au, Ni, AuGe, and AuGe / Ni / Au.

The light emitting device according to the embodiment may further include a high-concentration impurity semiconductor layer between the first electrode 60 and the first conductivity type semiconductor layer 11. For example, the high concentration impurity semiconductor layer may be formed of a GaAs layer. The heavily doped impurity semiconductor layer may include an impurity having the same polarity as that of the first conductivity type semiconductor layer 11. The heavily doped impurity semiconductor layer may include impurities at a higher concentration than the first conductivity type semiconductor layer 11.

The electrode pad 70 may be electrically connected to the first electrode 60. The electrode pad 70 may be disposed on the first electrode 60. The electrode pad 70 may be disposed in contact with the first electrode 60. The electrode pad 70 may be connected to an external power source to provide power to the light emitting structure 10.

According to an embodiment, the protective layer 80 may be disposed on the light emitting structure 10. The protective layer 80 may be disposed around the light emitting structure 10. The protective layer 80 may be disposed on a side surface of the light emitting structure 10. The protective layer 80 may be disposed around the window layer 15. A portion of the protective layer 80 may be disposed on a portion of the window layer 15.

3 and 4, it can be seen that the operating voltage and the luminous flux are changed according to the Al composition included in the light emitting structure 10 according to the embodiment. In addition, according to the embodiment, it was confirmed that the operating voltage and the luminous flux change tend to be different according to the shape of the first electrode 60 according to the Al composition.

That is, the operating voltage tends to increase as the Al composition increases, and it can be seen that the light flux tends to decrease as the Al composition increases. However, when the Al composition is larger than about 40%, it can be seen that the luminous flux in the case of forming 'star' with respect to 'circle' shows a larger value and the operating voltage shows a smaller value.

With reference to this tendency, the light emitting device according to the embodiment can provide the shape of the first electrode 60 according to the Al composition as follows. Here, the Al composition represents the compositional change of Al contained in the first conductivity type semiconductor layer 11. In addition, the lower surface area of the light emitting structure 10 may be 0.1 mm 2 or less. For example, the lower surface of the light emitting structure 10 may be provided with a width of 300 mu m both in the lateral and vertical directions.

According to the embodiment, when the first conductivity type semiconductor layer 11 includes a composition of (Al _x Ga _{1 -x} ) _y In _{1 -y} P (0.1? X? 0.4, 0 <y? 1) As shown in FIGS. 9 and 10, the first electrode 60 may be provided in a circular shape having a diameter of 120 micrometers or less. The first electrode 60 may be provided to have a diameter of 80 micrometers to 120 micrometers.

On the other hand, as shown in FIG. 10, the ohmic contact layer 23 may include a plurality of ohmic contact regions having a dot shape. For example, the width of the point shape of the ohmic contact layer 23 may be selected from 5 micrometers to 15 micrometers. The ohmic contact region of the point shape of the ohmic contact layer 23 may be provided with 20 to 40 ohmic contact regions.

According to the embodiment, the first electrode 60 and the plurality of ohmic contact regions may be arranged so as not to overlap each other in the vertical direction. Accordingly, the current applied to the light emitting structure 10 can be diffused and flowed, and the luminous efficiency can be improved.

11 is a view illustrating a light emitting device package to which the light emitting device according to the embodiment is applied.

Referring to FIG. 11, a light emitting device package according to an embodiment includes a body 120, first and second lead electrodes 131 and 132 disposed on the body 120, And a molding member 140 surrounding the light emitting device 100. The first and second lead electrodes 131 and 132 are electrically connected to the first and second lead electrodes 131 and 132, .

The body 120 may be formed of a silicon material, a synthetic resin material, or a metal material, and the inclined surface may be formed around the light emitting device 100.

The first lead electrode 131 and the second lead electrode 132 are electrically separated from each other to provide power to the light emitting device 100. The first lead electrode 131 and the second lead electrode 132 may increase the light efficiency by reflecting the light generated from the light emitting device 100 and the heat generated from the light emitting device 100 To the outside.

The light emitting device 100 may be disposed on the body 120 or may be disposed on the first lead electrode 131 or the second lead electrode 132.

The light emitting device 100 may be electrically connected to the first lead electrode 131 and the second lead electrode 132 by a wire, flip chip or die bonding method.

The molding member 140 may surround the light emitting device 100 to protect the light emitting device 100. In addition, the molding member 140 may include a phosphor to change the wavelength of light emitted from the light emitting device 100.

A plurality of light emitting devices or light emitting device packages according to the embodiments may be arrayed on a substrate, and a lens, a light guide plate, a prism sheet, a diffusion sheet, etc., which are optical members, 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. The light unit may be implemented as a top view or a side view type and may be provided in a display device such as a portable terminal and a notebook computer, or may be variously applied to a lighting device and a pointing device. Still another embodiment may be embodied as a lighting device including the light emitting device or the light emitting device package described in the above embodiments. For example, the lighting device may include a lamp, a streetlight, an electric signboard, and a headlight.

The light emitting device according to the embodiment can be applied to a light unit. The light unit includes a structure in which a plurality of light emitting elements are arrayed, and may include the display apparatus shown in Figs. 12 and 13, and the illumination apparatus shown in Fig.

12, a display device 1000 according to an embodiment includes a light guide plate 1041, a light emitting module 1031 for providing light to the light guide plate 1041, and a reflection member 1022 An optical sheet 1051 on the light guide plate 1041, a display panel 1061 on the optical sheet 1051, the light guide plate 1041, a light emitting module 1031, and a reflection member 1022 But is not limited to, a bottom cover 1011.

The bottom cover 1011, the reflective sheet 1022, the light guide plate 1041, and the optical sheet 1051 can be defined as a light unit 1050.

The light guide plate 1041 serves to diffuse light into a surface light source. The light guide plate 1041 may be made of a transparent material such as acrylic resin such as polymethyl methacrylate (PET), polyethylene terephthalate (PET), polycarbonate (PC), cycloolefin copolymer (COC), and polyethylene naphthalate Resin. &Lt; / RTI &gt;

The light emitting module 1031 provides light to at least one side of the light guide plate 1041, and ultimately acts as a light source of the display device.

At least one light emitting module 1031 may be provided, and light may be provided directly or indirectly from one side of the light guide plate 1041. The light emitting module 1031 may include a substrate 1033 and a light emitting device or a light emitting device package 200 according to the embodiment described above. The light emitting device package 200 may be arrayed on the substrate 1033 at predetermined intervals.

The substrate 1033 may be a printed circuit board (PCB) including a circuit pattern. However, the substrate 1033 may include not only a general PCB, but also a metal core PCB (MCPCB), a flexible PCB (FPCB), and the like. When the light emitting device package 200 is provided on the side surface of the bottom cover 1011 or on the heat dissipation plate, the substrate 1033 may be removed. Here, a part of the heat radiating plate may be in contact with the upper surface of the bottom cover 1011.

The plurality of light emitting device packages 200 may be mounted such that the light emitting surface of the light emitting device package 200 is spaced apart from the light guiding plate 1041 by a predetermined distance, but the present invention is not limited thereto. The light emitting device package 200 may directly or indirectly provide light to the light-incident portion, which is one side of the light guide plate 1041, but is not limited thereto.

The reflective member 1022 may be disposed under the light guide plate 1041. The reflection member 1022 reflects the light incident on the lower surface of the light guide plate 1041 so as to face upward, thereby improving the brightness of the light unit 1050. The reflective member 1022 may be formed of, for example, PET, PC, or PVC resin, but is not limited thereto. The reflective member 1022 may be an upper surface of the bottom cover 1011, but is not limited thereto.

The bottom cover 1011 may house the light guide plate 1041, the light emitting module 1031, the reflective member 1022, and the like. To this end, the bottom cover 1011 may be provided with a housing part 1012 having a box-like shape with an opened upper surface, but the present invention is not limited thereto. The bottom cover 1011 may be coupled to the top cover, but is not limited thereto.

The bottom cover 1011 may be formed of a metal material or a resin material, and may be manufactured using a process such as press molding or extrusion molding. In addition, the bottom cover 1011 may include a metal or a non-metal material having good thermal conductivity, but the present invention is not limited thereto.

The display panel 1061 is, for example, an LCD panel, including first and second transparent substrates facing each other, and a liquid crystal layer interposed between the first and second substrates. A polarizing plate may be attached to at least one surface of the display panel 1061, but the present invention is not limited thereto. The display panel 1061 displays information by light passing through the optical sheet 1051. Such a display device 1000 can be applied to various types of portable terminals, monitors of notebook computers, monitors of laptop computers, televisions, and the like.

The optical sheet 1051 is disposed between the display panel 1061 and the light guide plate 1041 and includes at least one light-transmitting sheet. The optical sheet 1051 may include at least one of a sheet such as a diffusion sheet, a horizontal and vertical prism sheet, and a brightness enhancement sheet. The diffusion sheet diffuses incident light, and the horizontal and / or vertical prism sheet condenses incident light into a display area. The brightness enhancing sheet improves the brightness by reusing the lost light. A protective sheet may be disposed on the display panel 1061, but the present invention is not limited thereto.

Here, the optical path of the light emitting module 1031 may include the light guide plate 1041 and the optical sheet 1051 as an optical member, but the present invention is not limited thereto.

13 is a view showing another example of the display device according to the embodiment.

13, the display device 1100 includes a bottom cover 1152, a substrate 1020 on which the above-described light emitting device 100 is arrayed, an optical member 1154, and a display panel 1155. The substrate 1020 and the light emitting device package 200 may be defined as a light emitting module 1060. The bottom cover 1152 may include a receiving portion 1153, but the present invention is not limited thereto.

Here, the optical member 1154 may include at least one of a lens, a light guide plate, a diffusion sheet, a horizontal and vertical prism sheet, and a brightness enhancement sheet. The light guide plate may be made of a PC material or a PMMA (poly methy methacrylate) material, and such a light guide plate may be removed. The diffusion sheet diffuses incident light, and the horizontal and vertical prism sheets condense incident light into a display area. The brightness enhancing sheet enhances brightness by reusing the lost light.

The optical member 1154 is disposed on the light emitting module 1060, and performs surface light source, diffusion, and light condensation of the light emitted from the light emitting module 1060.

14 is a view showing a lighting apparatus according to an embodiment.

14, the lighting apparatus according to the embodiment includes a cover 2100, a light source module 2200, a heat discharger 2400, a power supply unit 2600, an inner case 2700, and a socket 2800 . Further, the illumination device according to the embodiment may further include at least one of the member 2300 and the holder 2500. The light source module 2200 may include a light emitting device package according to an embodiment.

For example, the cover 2100 may have a shape of a bulb or a hemisphere, and may be provided in a shape in which the hollow is hollow and a part is opened. The cover 2100 may be optically coupled to the light source module 2200. For example, the cover 2100 may diffuse, scatter, or excite light provided from the light source module 2200. The cover 2100 may be a kind of optical member. The cover 2100 may be coupled to the heat discharging body 2400. The cover 2100 may have an engaging portion that engages with the heat discharging body 2400.

The inner surface of the cover 2100 may be coated with a milky white paint. Milky white paints may contain a diffusing agent to diffuse light. The surface roughness of the inner surface of the cover 2100 may be larger than the surface roughness of the outer surface of the cover 2100. This is for sufficiently diffusing and diffusing the light from the light source module 2200 and emitting it to the outside.

The cover 2100 may be made of glass, plastic, polypropylene (PP), polyethylene (PE), polycarbonate (PC), or the like. Here, polycarbonate is excellent in light resistance, heat resistance and strength. The cover 2100 may be transparent so that the light source module 2200 is visible from the outside, and may be opaque. The cover 2100 may be formed by blow molding.

The light source module 2200 may be disposed on one side of the heat discharging body 2400. Accordingly, heat from the light source module 2200 is conducted to the heat discharger 2400. The light source module 2200 may include a light source unit 2210, a connection plate 2230, and a connector 2250.

The member 2300 is disposed on the upper surface of the heat discharging body 2400 and has guide grooves 2310 through which the plurality of light source portions 2210 and the connector 2250 are inserted. The guide groove 2310 corresponds to the substrate of the light source unit 2210 and the connector 2250.

The surface of the member 2300 may be coated or coated with a light reflecting material. For example, the surface of the member 2300 may be coated or coated with a white paint. The member 2300 reflects the light reflected by the inner surface of the cover 2100 toward the cover 2100 in the direction toward the light source module 2200. Therefore, the light efficiency of the illumination device according to the embodiment can be improved.

The member 2300 may be made of an insulating material, for example. The connection plate 2230 of the light source module 2200 may include an electrically conductive material. Therefore, electrical contact can be made between the heat discharging body 2400 and the connecting plate 2230. The member 2300 may be formed of an insulating material to prevent an electrical short circuit between the connection plate 2230 and the heat discharging body 2400. The heat discharger 2400 receives heat from the light source module 2200 and heat from the power supply unit 2600 to dissipate heat.

The holder 2500 blocks the receiving groove 2719 of the insulating portion 2710 of the inner case 2700. Therefore, the power supply unit 2600 housed in the insulating portion 2710 of the inner case 2700 is sealed. The holder 2500 has a guide protrusion 2510. The guide protrusion 2510 has a hole through which the protrusion 2610 of the power supply unit 2600 passes.

The power supply unit 2600 processes or converts an electrical signal provided from the outside and provides the electrical signal to the light source module 2200. The power supply unit 2600 is housed in the receiving groove 2719 of the inner case 2700 and is sealed inside the inner case 2700 by the holder 2500.

The power supply unit 2600 may include a protrusion 2610, a guide 2630, a base 2650, and an extension 2670.

The guide portion 2630 has a shape protruding outward from one side of the base 2650. The guide portion 2630 may be inserted into the holder 2500. A plurality of components may be disposed on one side of the base 2650. The plurality of components include, for example, a DC converter for converting AC power supplied from an external power source into DC power, a driving chip for controlling driving of the light source module 2200, an ESD (ElectroStatic discharge) protective device, and the like, but the present invention is not limited thereto.

The extension portion 2670 has a shape protruding outward from the other side of the base 2650. The extension portion 2670 is inserted into the connection portion 2750 of the inner case 2700 and receives an external electrical signal.

For example, the extension portion 2670 may be provided to be equal to or smaller than the width of the connection portion 2750 of the inner case 2700. One end of each of the positive wire and the negative wire is electrically connected to the extension portion 2670 and the other end of the positive wire and the negative wire are electrically connected to the socket 2800 .

The inner case 2700 may include a molding part together with the power supply part 2600. The molding part is a hardened portion of the molding liquid so that the power supply unit 2600 can be fixed inside the inner case 2700.

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 one embodiment. Further, the features, structures, effects, and the like illustrated in the embodiments can be combined and modified by other persons having ordinary skill 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.

10 Light emitting structure 11 First conductive type semiconductor layer
12 active layer 13 second conductive semiconductor layer
15 window layer 21 ODR layer
23 ohmic contact layer 30 reflective layer
40 bonding layer 50 Support substrate
60 first electrode 61 main electrode
63 peripheral electrode 70 electrode pad
80 protective layer

Claims (9)

A light emitting structure including a first conductive semiconductor layer, an active layer disposed under the first conductive semiconductor layer, and a second conductive semiconductor layer disposed under the active layer;
A window layer disposed below the light emitting structure;
A reflective layer disposed below the window layer;
A first electrode disposed on the light emitting structure and electrically connected to the first conductive semiconductor layer;
/ RTI &gt;
Wherein the first conductive semiconductor layer includes a composition of (Al _x Ga _{1 -x} ) _y In _{1 -y} P (0.4 <x? 0.8, 0 <y? 1)
Wherein the first electrode includes a main electrode and a peripheral electrode extending from the main electrode to the periphery,
Wherein the main electrode of the first electrode is provided in a circular shape having a diameter of 120 micrometers or less. A light emitting structure including a first conductive semiconductor layer, an active layer disposed under the first conductive semiconductor layer, and a second conductive semiconductor layer disposed under the active layer;
A window layer disposed below the light emitting structure;
A reflective layer disposed below the window layer;
A first electrode disposed on the light emitting structure and electrically connected to the first conductive semiconductor layer;
/ RTI &gt;
Wherein the first conductive semiconductor layer includes a composition of (Al _x Ga _{1 -x} ) _y In _{1 -y} P (0.1? X? 0.4, 0 <y? 1)
Wherein the first electrode is provided in a circular shape having a diameter of 120 micrometers or less. 3. The method according to claim 1 or 2,
And the lower surface area of the light emitting structure is 0.1 mm 2 or less. 3. The method according to claim 1 or 2,
And an ohmic contact layer disposed under the window layer and electrically connected to the second conductive semiconductor layer. 5. The method of claim 4,
Wherein the ohmic contact layers are spaced apart from each other and arranged in a plurality of dots, the ohmic contact layers being in ohmic contact with the window layer. 6. The method of claim 5,
And a width of the ohmic contact region arranged in a point shape of the ohmic contact layer is 5 micrometers to 15 micrometers. The light emitting device according to claim 4, wherein the first electrode and the plurality of ohmic contact regions are arranged so as not to overlap each other in the vertical direction. 3. The method according to claim 1 or 2,
Wherein the reflective layer comprises a metal layer. 3. The method according to claim 1 or 2,
Wherein the window layer comprises a GaP semiconductor layer.

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