KR20120133834A - Light emitting device and Manufacturing method for light emitting device - Google Patents

Abstract

A light emitting device according to an embodiment includes a light emitting structure including a first semiconductor layer, a second semiconductor layer, and an active layer formed between the first semiconductor layer and the second semiconductor layer; And a first light extracting structure formed on the second semiconductor layer, wherein the first light extracting structure includes a plurality of uneven portions, and side cross-sections of the uneven portions form an effervescent triangle having different inclinations of both sides. .

Description

Light emitting device and manufacturing method for light emitting device

The embodiment relates to a light emitting device and a light emitting device manufacturing method.

LED (Light Emitting Diode) is a device that converts electrical signals into infrared, visible light or light using the characteristics of compound semiconductors. It is used in household appliances, remote controls, display boards, The use area of LED is becoming wider.

In general, miniaturized LEDs are made of a surface mounting device for mounting directly on a PCB (Printed Circuit Board) substrate, and an LED lamp used as a display device is also being developed as a surface mounting device type . Such a surface mount device can replace a conventional simple lighting lamp, which is used for a lighting indicator for various colors, a character indicator, an image indicator, and the like.

As the use area of the LED is widened as described above, it is important to increase the luminance of the LED as the brightness required for a lamp used in daily life and a lamp for a structural signal is increased.

An embodiment is to provide a light emitting device having improved internal quantum efficiency and light extraction efficiency.

A light emitting device according to an embodiment includes a light emitting structure including a first semiconductor layer, a second semiconductor layer, and an active layer formed between the first semiconductor layer and the second semiconductor layer; And a first light extracting structure formed on the second semiconductor layer, wherein the first light extracting structure includes a plurality of uneven portions, and side cross-sections of the uneven portions form an effervescent triangle having different inclinations of both sides. .

In the light emitting device according to the embodiment, since the light extraction structures having different side slopes are formed, the light extraction efficiency of the light emitting device can be improved.

In addition, since the light extraction structure is densely formed, the light extraction efficiency of the light emitting device can be improved.

In addition, since the light extraction structure is formed together during the growth of the semiconductor layer, the etching process for forming the light extraction structure can be omitted, thereby reducing manufacturing cost and manufacturing time, and damage to the light emitting device by the etching process. And damage can be prevented.

In addition, since the light emitting structure of the light emitting device is formed to have a non-polar or semi-polar growth surface, quantum efficiency and crystal defects of the light emitting device can be improved.

In addition, since the side of the light emitting structure is formed to have a polarity, it is possible to easily form a light extraction structure on the side of the light emitting device through a wet etching process can be improved economic efficiency and reliability of the light emitting device and the light emitting device manufacturing process.

1A to 1D are diagrams illustrating each surface of a hexagonal crystal structure as a reference drawing for explaining the crystal structure of the substrate and the nitride semiconductor layer;
2A and 2B illustrate a growth pattern when growing a semiconductor layer having a first growth surface on a growth substrate having a second growth surface;
3A is a sectional view showing a light emitting device according to the embodiment;
3B is an enlarged fragmentary view of a region A of FIG. 3A;
3C is a conceptual diagram illustrating an uneven portion forming a light extraction structure of the light emitting device according to the embodiment;
3D is a sectional view showing a light emitting device according to the embodiment;
4 is a view showing a light extraction structure of a light emitting device according to the prior art;
5 is a view showing a light extraction structure of a light emitting device according to the embodiment;
6A is a sectional view showing a light emitting device according to the embodiment;
FIG. 6B is an enlarged view of a portion B of FIG. 6A;
6C is a conceptual diagram illustrating an uneven portion forming a light extraction structure of a light emitting device according to an embodiment;
6D is a sectional view showing a light emitting device according to the embodiment;
6E is a sectional view showing a light emitting device according to the embodiment;
7 is a view illustrating a step in which a nitride semiconductor layer is grown on a growth substrate to form a light emitting structure;
8 is a view illustrating a step in which a first light extracting structure is formed on a light emitting structure;
9A is a view illustrating a step of forming an electrode by removing a part of the light emitting structure;
9B is a view illustrating a step of forming a second light extracting structure by etching the light emitting structure;
10 is a view showing a step in which a nitride semiconductor layer is grown on a growth substrate to form a light emitting structure;
11 is a view showing a step in which a first light extracting structure is formed on a light emitting structure;
12 illustrates bonding the support substrate on the light emitting structure and removing the growth substrate;
13A is a view illustrating a step of forming a second electrode layer on a light emitting structure;
13B is a view showing a step of forming a second light extracting structure on a light emitting structure;
13C is a view showing a step of forming a third light extracting structure on a light emitting structure;
14A is a perspective view of a light emitting device package including a light emitting device according to the embodiment;
14B is a cross-sectional view of the light emitting device package shown in FIG. 14A;
15A is a perspective view of a lighting system including a light emitting device according to the embodiment;
FIG. 15B is a sectional view showing a section CC ′ of the lighting system of FIG. 15A; FIG.
16 is an exploded perspective view of a liquid crystal display device including a light emitting device according to the embodiment;
17 is an exploded perspective view of a liquid crystal display including the light emitting device according to the embodiment.

In the description of embodiments, each layer, region, pattern, or structure is “under” a substrate, each layer (film), region, pad, or “on” of a pattern or other structure. In the case of being described as being formed on the upper or lower, the "on", "under", upper, and lower are "direct" "directly" or "indirectly" through other layers or structures.

In addition, the description of the positional relationship between each layer or structure, please refer to this specification, or drawings attached to this specification.

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

Hereinafter, a light emitting device according to an embodiment will be described with reference to the accompanying drawings.

1A to 1D are reference views for explaining a crystal structure of a growth substrate and a nitride semiconductor layer, and include C-plane {0001}, A-plane {11-20}, and R-plane {1-102 of a hexagonal crystal structure. }, The M-plane {1-100} is shown.

The nitride semiconductor layer and its alloys are most stable in hexagonal crystal structure (especially hexagonal wurzite structure). This crystal structure has three basic axes [a ₁ , a ₂ , which have a rotational symmetry of 120 degrees with respect to each other, as shown in FIGS. 1a to 1d, and are all perpendicular to the vertical C-axis [0001]. a ₃ ].

The decision direction index is [0000], the family index of the decision direction index equivalent to one decision direction index is indicated as <0000>, the face direction index is (0000), and the family index of the face direction index equivalent to the one direction direction index Is represented by {0000}.

Therefore, the A-plane {11-20} described above is not only the (11-20) plane, but also the crystal plane that appears when the hexagonal crystal structure is rotated by 60 degrees about the C-axis [0001], that is, (-1-120). ), (-12-10), (1-210), (-2110), (2-1-10) shaving A-plane {11-20}.

Similarly, the R-plane {1-102} is not only the (1-102) plane, but also the crystal plane resulting from rotating the hexagonal crystal structure by 60 degrees about the C-axis [0001], that is, (-1102), (10 -12), (-1012), (01-12), (0-112) shaving R-plane {1-102}.

Similarly, the M-plane {1-100} is not only the (1-100) plane, but also the crystal plane that appears when the hexagonal crystal structure is rotated by 60 degrees about the C-axis [0001], that is, (-1100), (10 -10), (-1010), (01-10), and (0-110) shaving R-planes {1-102}.

1A to 1D, the growth substrate and the nitride semiconductor layer have a hexagonal crystal structure. That is, the growth substrate may be formed of a material having a hexagonal crystal structure, for example, sapphire (Al ₂ O ₃ ), SiC, GaAs, GaN, ZnO, or the like.

When the nitride semiconductor layer is grown on the substrate having the crystal structure shown in the drawing, when the nitride semiconductor layer is grown in the C-plane {0001} direction, the nitride thin film is easily grown and is used as a substrate for nitride growth because it is stable at high temperatures. However, the nitride semiconductor layer grown in the C-plane {0001} direction has a polarization effect. This polarization effect includes the lattice constant difference between the nitrides and the same C-axis when forming a heterojunction structure with spontaneous polarizaion, in which symmetrical elements included in the crystal structure are formed along the C-axis while the gallium and nitrogen layers are repeatedly stacked. There is a piezoelectric polariziton caused by the generation of stress due to the property of orientation. The piezoelectric coefficient of nitride has a large value compared to almost all semiconductor materials, and can cause very large polarization even with small strains. The electric field caused by the two polarizations changes the energy band structure of the quantum well structure, thereby distorting the distribution of electrons and holes. This effect is called the quantum confined stark effect (QCSE), which causes low internal quantum efficiency in light emitting devices that generate light by recombination of electrons and holes, and emits light such as red shift in the emission spectrum. It may adversely affect the electrical and optical characteristics of the device. In addition, the fast growth rate of the C-plane {0001} tends to increase crystal defects in the nitride semiconductor layer.

In the hexagonal crystal structure, the A-plane {11-20}, the R-plane {1-102}, and the M-plane {1-100} are non-polar or semipolar planes, and the C-plane {0001} The growth of the nitride semiconductor layer is difficult, but it does not generate an electrostatic field due to the polarization effect occurring in the C-plane {0001}, or the generation of the electrostatic field is reduced.

On the other hand, in the gallium nitride (GaN) crystal structure, the nonpolar planes are M-planes {1-100} and A-planes {11-20} parallel to the C-axis [0001], and the semipolar planes are C-axis [ 0001] and an R-plane {1-102} having an inclination.

2A and 2B are views showing a growth pattern when growing a semiconductor layer having a first growth surface on a growth substrate having a second growth surface.

Here, the second growth surface 240 refers to one surface of the growth substrate 210 on which the nitride semiconductor layer 220 is grown, and the first growth surface 230 is a nitride semiconductor layer grown on the growth substrate 210 ( It means a plane perpendicular to the growth direction of 220).

In the embodiment, a sapphire substrate is used as the growth substrate 210 to manufacture the light emitting device, but is not limited thereto. For example, a conductive or insulating substrate such as SiC may be used.

2A and 2B, the first growth surface 230 may be an A-plane {11-20}, and the second growth surface 240 may be an R-plane {1-120}. The first growth surface 230 may form a first crystal direction d1, and the second growth surface 240 may form a second crystal direction d2. As the first growth surface 230 is the A-plane {11-20}, the first crystal direction d1 may be in the <11-20> direction.

Since the first growth surface 230 of the nitride semiconductor layer 220 and the second growth surface 240 of the growth substrate 210 are nonpolar or semipolar surfaces, the piezoelectric polarization effect is suppressed to improve internal quantum efficiency of the light emitting device. And crystal defects can be improved.

Meanwhile, since the first growth surface 230 of the nitride semiconductor layer 220 is a nonpolar or semipolar crystal surface, a C-plane {0001} may be formed on the side surface 226 of the nitride semiconductor layer 220, and thus C Ga-face or N-face of -plane {0001} may be formed on the side surface 226 of the nitride semiconductor layer 220.

Ga-face and N-face of the C-plane {0001} can be easily etched through a wet etching process, the nitride when the first growth surface 230 of the nitride semiconductor layer 220 is a non-polar or semi-polar crystal surface The side surface 226 of the semiconductor layer 220 may be easily etched through a wet etching process, and thus a light extraction structure such as an uneven structure may be formed on the side surface 226 of the nitride semiconductor layer 220.

On the other hand, during the growth process of the nitride semiconductor layer 220, by varying at least one of the growth pressure, the growth temperature, the predetermined additive input conditions, and the source input conditions, the upper surface of the nitride semiconductor layer 220 is shown in Figure 2b As shown in FIG. 2A, a peak 224 that forms irregularities in the first crystal direction d1 may protrude. On the other hand, as shown in the figure, the top surface of the semiconductor layer is formed a peak 224 to form the unevenness in the first crystal direction d1, so that the top surface of the nitride semiconductor layer 220 during the growth process of the nitride semiconductor layer 220 It may have a roughness and an uneven portion may be formed to form a light extraction structure. This will be described later.

3A is a cross-sectional view illustrating a light emitting device according to an embodiment, FIG. 3B is a partially enlarged view illustrating region A of FIG. 3A, and FIG. 3C is a conceptual view illustrating an uneven portion forming a light extraction structure of the light emitting device according to the embodiment. 3D and 3E are cross-sectional views showing light emitting devices according to the embodiment.

Referring to FIG. 3A, the light emitting device 300 may include a support member 310 and a light emitting structure 360 disposed on the support member 310, and the light emitting structure 360 may include the first semiconductor layer 320. ), An active layer 330, an intermediate layer 340, and a second semiconductor layer 350.

The support member 310 may be formed of a material having a light transmitting property, for example, any one of sapphire (Al ₂ O ₃ ), GaN, ZnO, AlO, but is not limited thereto. In addition, the SiC support member may have a higher thermal conductivity than sapphire (Al ₂ O ₃ ).

Meanwhile, a PSS (Patterned SubStrate) structure may be provided on the upper surface of the support member 310 to increase light extraction efficiency. The support member 310 referred to herein may or may not have a PSS structure.

Meanwhile, a buffer layer (not shown) may be disposed on the support member 310 to mitigate lattice mismatch between the support member 310 and the first semiconductor layer 320 and to easily grow the semiconductor layer. The buffer layer (not shown) may be formed in a low temperature atmosphere, and may be formed of a material capable of alleviating the difference in lattice constant between the semiconductor layer and the support member. For example, materials such as GaN, InN, AlN, AlInN, InGaN, AlGaN, and InAlGaN can be selected and not limited thereto. The buffer layer (not shown) may grow as a single crystal on the support member 310, and the buffer layer (not shown) grown as the single crystal may improve the crystallinity of the first semiconductor layer 320 grown on the buffer layer (not shown). Can be.

The light emitting structure 360 including the first semiconductor layer 320, the active layer 330, and the second semiconductor layer 350 may be formed on the buffer layer (not shown).

The first semiconductor layer 320 may be positioned on the buffer layer (not shown). The first semiconductor layer 320 may be implemented as an n-type semiconductor layer, and may provide electrons to the active layer 330. The first semiconductor layer 320 is, for _{example, In x Al y Ga 1 -x-} y N (0 = x = 1, 0 = y = 1, 0 = x + y = 1) semiconductor material having a compositional formula of For example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, etc. may be selected, and n-type dopants such as Si, Ge, Sn, and the like may be doped.

In addition, an undoped semiconductor layer (not shown) may be further included below the first semiconductor layer 320, but embodiments are not limited thereto. The undoped semiconductor layer is a layer formed to improve the crystallinity of the first semiconductor layer 320, except that the n-type dopant is not doped and thus has a lower electrical conductivity than the first semiconductor layer 320. It may be the same as the semiconductor layer 320.

An active layer 330 may be formed on the first semiconductor layer 320. The active layer 330 may be formed of a single or multiple quantum well structure, a quantum-wire structure, a quantum dot structure, or the like using a compound semiconductor material of a group III-V group element.

For example, when the active layer 330 has a quantum well structure, a well having a composition formula of In _x Al _y Ga _{1 -x- y} N (0 = x = 1, 0 = y = 1, 0 = x + y = 1) _Have a single or multiple quantum well structure having a layer and a barrier layer having a compositional formula of In _a Al _b Ga _{1 -a- b} N (0 = a = 1, 0 = b = 1, 0 = a + b = 1). Can be. The well layer may be formed of a material having a band gap smaller than the band gap of the barrier layer.

A conductive clad layer (not shown) may be formed on or under the active layer 330. The conductive cladding layer (not shown) may be formed of an AlGaN-based semiconductor, and may have a band gap larger than that of the active layer 330.

The second semiconductor layer 350 may be implemented as a p-type semiconductor layer to inject holes into the active layer 330. A second semiconductor layer 350, for _{example, In x Al y Ga 1 -x-} y N (0 = x = 1, 0 = y = 1, 0 = x + y = 1) semiconductor material having a compositional formula of For example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, etc. may be selected, and p-type dopants such as Mg, Zn, Ca, Sr, and Ba may be doped.

Meanwhile, an intermediate layer 340 may be formed between the active layer 330 and the second semiconductor layer 350, and the intermediate layer 340 is injected into the active layer 330 from the first semiconductor layer 320 when a high current is applied. The electron may be an electron blocking layer that prevents electrons from recombining in the active layer 330 and flows into the second semiconductor layer 350. The intermediate layer 340 has a band gap relatively larger than that of the active layer 330, so that electrons injected from the first semiconductor layer 330 are injected into the second semiconductor layer 350 without recombination in the active layer 330. Can be prevented. Accordingly, the probability of recombination of electrons and holes in the active layer 340 may be increased and leakage current may be prevented.

The intermediate layer 340 may have a band gap larger than that of the barrier layer included in the active layer 330, and may be formed of a semiconductor layer including Al, such as p-type AlGaN, but is not limited thereto. .

The first semiconductor layer 320, the active layer 330, the intermediate layer 340, and the second semiconductor layer 350 may be, for example, metal organic chemical vapor deposition (MOCVD) or chemical vapor deposition (MOCVD). Chemical Vapor Deposition (CVD), Plasma-Enhanced Chemical Vapor Deposition (PECVD), Molecular Beam Epitaxy (MBE), Hydride Vapor Phase Epitaxy (HVPE), Sputtering It may be formed using a method such as, but is not limited thereto.

In addition, the doping concentrations of the conductive dopants in the first semiconductor layer 320 and the second semiconductor layer 350 may be uniformly or non-uniformly formed. That is, the plurality of semiconductor layers may be formed to have various doping concentration distributions, but the invention is not limited thereto.

In addition, the first semiconductor layer 320 may be implemented as a p-type semiconductor layer, the second semiconductor layer 350 may be implemented as an n-type semiconductor layer, and the n-type or p-type semiconductor is formed on the second semiconductor layer 350. A third semiconductor layer (not shown) including a layer may be formed. Accordingly, the light emitting device 300 may have at least one of np, pn, npn, and pnp junction structures.

Meanwhile, a portion of the active layer 330 and the second semiconductor layer 350 may be removed to expose a portion of the first semiconductor layer 320, and the first electrode 372 may be exposed on the exposed first semiconductor layer 320. This can be formed. That is, the first semiconductor layer 320 includes an upper surface facing the active layer 330 and a lower surface facing the support member 310, and the upper surface includes a region at least one region is exposed, and the first electrode 372 is It may be disposed on the exposed area of the upper surface.

Meanwhile, a method of exposing a portion of the first semiconductor layer 320 may use a predetermined etching method, but is not limited thereto. The etching method may be a wet etching method or a dry etching method.

In addition, a second electrode 374 and a first light extracting structure 380 may be formed on the second semiconductor layer 350.

Meanwhile, the first and second electrodes 372 and 374 may be conductive materials, for example, In, Co, Si, Ge, Au, Pd, Pt, Ru, Re, Mg, Zn, Hf, Ta, Rh, Ir, W It may include a metal selected from Ti, Ag, Cr, Mo, Nb, Al, Ni, Cu, and WTi, or may include an alloy thereof, may be formed in a single layer or multiple layers, but is not limited thereto. .

The first light extracting structure 380 may be formed in a portion or the entire area of the upper surface of the second semiconductor layer 350.

The first light extracting structure 380 may be formed by varying at least one of a growth temperature, a growth pressure, a source input condition, and other additive supply conditions during the growth of the second semiconductor layer 350, but is not limited thereto. . As the first light extracting structure 380 is formed on the second semiconductor layer 350, the second semiconductor layer 350 may include an uneven portion forming the first light extracting structure 380.

The uneven portion may be irregularly formed in a random size, but is not limited thereto. The uneven portion is an uneven upper surface and may include at least one of a texture pattern, an uneven pattern, and an uneven pattern.

As the first light extracting structure 380 is formed on the top surface of the transparent electrode layer (not shown) or the second semiconductor layer 350, the light generated from the active layer 330 is formed on the top surface of the second semiconductor layer 350. Since it can be totally reflected from the re-absorbed or scattered, it can contribute to the improvement of the light extraction efficiency of the light emitting device (300).

On the other hand, the uneven portion may have the form of an effervescent triangle having different slopes of both sides as shown in FIG. 3B. That is, each of θ1 and θ2 may have a different value from each other.

By forming an uneven portion having an elongated triangular cross-section having different inclinations at both sides, the range of the incident angle at which total reflection of light generated in the active layer 330 is prevented can be wider, and thus light extraction of the light emitting device 300 is performed. Efficiency can be improved.

On the other hand, the inclination θ1 and θ2 of the side of the uneven portion may have a slope of 30 ° to 60 °, respectively, the peak θ3 of the uneven portion may be formed at a right angle, but is not limited thereto.

Meanwhile, the height h1 of the uneven portion forming the first light extracting structure 380 may be 100 nm to 500 nm, and the width w1 of the uneven portion may have a value of 1.5 to 1.8 times the height h1 of the uneven portion. Not.

Meanwhile, as shown in FIG. 3B, the uneven parts forming the first light extracting structure 380 may be deflected in one direction, or each of the uneven parts may be deflected in different directions from each other. Not.

Meanwhile, the uneven portion may have a bottom surface S1 as shown in FIG. 3C. Since the bottom surface S1 of the uneven portion is formed to have a rectangular shape, the uneven portion may have a shape such as a square pyramid and a square pyramid.

Since the bottom surface S1 of the uneven portion is formed in a quadrangle, the first light extracting structure 380 having a more compact structure can be formed, and thus the light extraction efficiency of the light emitting device 300 can be improved. For example, 4 to 10 uneven parts may be formed in an area of 1 um ² .

Meanwhile, as illustrated in FIG. 3D, a second light extracting structure 382 may be formed on the side surface of the light emitting structure 360.

As described above, since the first growth surface of the nitride semiconductor layer forming the light emitting structure 360 is a nonpolar or semipolar crystal surface, the C-plane {0001} may be formed on the side surface of the light emitting structure 360, and thus Ga-face or N-face of the C-plane {0001} may be formed on the side of the light emitting structure (360).

Ga-face and N-face of the C-plane {0001} can be easily etched through the wet etching process, the side surface of the light emitting structure 360 can be easily etched through the wet etching process, thus the uneven portion A second light extracting structure 382 may be formed on the side surface of the light emitting structure 360.

4 is a view showing a light extraction structure of the light emitting device according to the prior art, Figure 5 is a view showing a light extraction structure of the light emitting device according to the embodiment.

First, referring to FIG. 4, the light extracting structure of the light emitting device according to the related art has a relatively non-dense distribution, and thus it can be understood that a flat region on the light emitting structure remains extensively. Therefore, the light generated in the active layer is totally reflected at the interface of the light emitting structure to reduce the light extraction efficiency and the light emitting efficiency of the light emitting device.

Subsequently, referring to FIG. 5, the light emitting device according to the embodiment may identify a light extraction structure in which the uneven portion having a relatively dense distribution is formed. Therefore, the light generated in the active layer is prevented from total reflection at the interface on the light emitting structure can be improved light extraction efficiency and luminous efficiency of the light emitting device.

6A is a cross-sectional view showing a light emitting device according to the embodiment, FIG. 6B is a partially enlarged view showing a region B of FIG. 6D and 6E are cross-sectional views showing light emitting devices according to the embodiment.

Referring to FIG. 6A, the light emitting device 400 according to the embodiment may include a support member 410, a first electrode layer 420, a first semiconductor layer 430, and an active layer 450 disposed on the support member 410. And a light emitting structure 470 including a second semiconductor layer 460, and a second electrode layer 480.

The support member 410 may be formed using a material having excellent thermal conductivity, and may be formed of a conductive material, and may be formed using a metal material or a conductive ceramic. The support member 410 may be formed of a single layer and may be formed of a double structure or multiple structures.

That is, the support member 410 may be formed of any one selected from a metal, for example, Au, Ni, W, Mo, Cu, Al, Ta, Ag, Pt, or Cr, or may be formed of two or more alloys. The above materials can be laminated and formed. In addition, the support member 410 is Si, Ge, GaAs, ZnO, SiC, SiGe, GaN, Ga ₂ O ₃ It may be implemented as a carrier wafer such as.

The support member 410 may facilitate the emission of heat generated from the light emitting device 400 to improve the thermal stability of the light emitting device 400.

The first electrode layer 420 may be formed on the supporting member 410, and the first electrode layer 420 may be an ohmic layer (not shown), a reflective layer (not shown), or a bonding layer. It may include at least one layer (bonding layer) (not shown). For example, the first electrode layer 420 may be a structure of an ohmic layer / reflective layer / bonding layer, a stacked structure of an ohmic layer / reflective layer, or a structure of a reflective layer (including ohmic) / bonding layer, but is not limited thereto. For example, the first electrode layer 420 may have a form in which a reflective layer and an ohmic layer are sequentially stacked on the insulating layer.

The reflective layer (not shown) may be disposed between the ohmic layer (not shown) and the insulating layer (not shown), and have excellent reflective properties such as Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg , Zn, Pt, Au, Hf, or a combination of these materials, or a combination of these materials or IZO, IZTO, IAZO, IGZO, IGTO, AZO, ATO, to form a multi-layer using a transparent conductive material such as Can be. Further, the reflective layer (not shown) can be laminated with IZO / Ni, AZO / Ag, IZO / Ag / Ni, AZO / Ag / Ni and the like. In addition, when the reflective layer (not shown) is formed of a material in ohmic contact with the light emitting structure 470 (for example, the first semiconductor layer 430), the ohmic layer (not shown) may not be separately formed, and the like is limited thereto. I do not.

The ohmic layer (not shown) is in ohmic contact with the bottom surface of the light emitting structure 470, and may be formed in a layer or a plurality of patterns. The ohmic layer (not shown) may be formed of a transparent electrode layer and a metal. For example, ITO (indium tin oxide), IZO (indium zinc oxide), IZTO (indium zinc tin oxide) ), IGZO (indium gallium zinc oxide), IGTO (indium gallium tin oxide), AZO (aluminum zinc oxide), ATO (antimony tin oxide), GZO (gallium zinc oxide), IrO _x , RuO _x , RuO _x / Ni, Ag, Ni / IrO _x / Au, and Ni / IrO _x / Au / ITO. The ohmic layer (not shown) is for smoothly injecting a carrier into the first semiconductor layer 430 and is not necessarily formed.

In addition, the first electrode layer 420 may include a bonding layer (not shown), wherein the bonding layer (not shown) may be a barrier metal or a bonding metal such as Ti, Au, Sn, and Ni. It may include, but is not limited to, at least one of Cr, Ga, In, Bi, Cu, Ag, or Ta.

The light emitting structure 470 may include at least a first semiconductor layer 430, an active layer 450, and a second semiconductor layer 460, between the first semiconductor layer 430 and the second semiconductor layer 460. The active layer 450 may be formed in the configuration shown.

The first semiconductor layer 430 may be formed on the first electrode layer 420. The first semiconductor layer 430 may be implemented as a p-type semiconductor layer doped with a p-type dopant. The p-type semiconductor layer contains a semiconductor material, for example, having a compositional formula of _{In x Al y Ga 1 -x- y} N (0 = x = 1, 0 = y = 1, 0 = x + y = 1) GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN and the like may be selected, and p-type dopants such as Mg, Zn, Ca, Sr, and Ba may be doped.

Meanwhile, a first light extracting structure 492 may be formed under the first semiconductor layer 430.

The first light extracting structure 492 may be formed on a portion or the entire area of the lower surface of the first semiconductor layer 430. The first light extracting structure 492 may be formed by varying at least one of a growth temperature, a growth pressure, a source input condition, and a predetermined additive input condition during the growth of the first semiconductor layer 430, but is not limited thereto. No. As the first light extracting structure 492 is formed under the first semiconductor layer 430, the first semiconductor layer 430 may include an uneven portion forming the first light extracting structure 492.

The uneven portion includes several protrusions protruding below the first semiconductor layer 430 and a depression formed between the protrusions, and may be irregularly formed in a random size, but are not limited thereto.

As the first light extracting structure 492 is formed under the first semiconductor layer 430, the light generated in the active layer 450 is an interface between the lower first semiconductor layer 430 and the first electrode layer 420. Can be prevented from being absorbed or lost. In addition, when the light generated in the active layer 450 proceeds downward, the light may be reflected by the lower first light extracting structure 492 with a larger direction angle, or reflected by the lower first electrode layer 420. When the light passes through the first light extracting structure 492, the light may have a larger directing angle, so that light extraction efficiency, light emission luminance, and light distribution of the light emitting device 400 may be improved.

On the other hand, the uneven portion may have a cross section in the form of an effervescent triangle having different inclinations of both sides as shown in FIG. 6B. That is, each of θ4 and θ5 may have a different value from each other.

By forming an uneven portion having an elongated triangular cross-section having different inclinations at both sides, the range of the incident angle at which total reflection of light generated in the active layer 450 is prevented can be wider, and thus light extraction of the light emitting device 400 is performed. Efficiency can be improved.

Meanwhile, as illustrated in FIG. 6B, the first light extracting structure 492 may be formed to be deflected in one direction, or may be formed to be deflected in different directions from each other, but is not limited thereto. On the other hand, the inclination θ4 and θ5 of the side of each concave-convex portion may have an inclination of 30 ° to 60 °, respectively, and the peak θ6 of each concave-convex portion may be formed at right angles, but is not limited thereto.

On the other hand, if the size of the uneven portion is large or small, since the light extraction efficiency of the light emitting device 400 may be reduced, the height h2 of the uneven portion may be from 100 nm to 500 nm, the width w2 of the uneven portion h2 is the height of the uneven portion It may have a value of 1.5 to 1.8 times, but is not limited thereto.

Meanwhile, as shown in FIG. 6C, each uneven portion may have a bottom surface S2 having a rectangular shape. Since the bottom surface S2 of the uneven portion is formed to have a quadrangular shape, the uneven portion may have, for example, an inverted square pyramid or a square pyramid.

Since the bottom surface S2 of the uneven portion is formed in a quadrangle, the first light extracting structure 492 having a more compact structure can be formed, and thus the light extraction efficiency of the light emitting device 400 can be improved. For example, 4 to 10 uneven parts may be formed in an area of 1 um ² .

Meanwhile, the first light extracting structure 492 including the uneven portion is formed under the first semiconductor layer 430, whereby the first semiconductor layer 430 and the first electrode layer 420 under the first semiconductor layer 430. ), The contact area between the?) Increases, so that the bonding between the light emitting structure 470 and the first electrode layer 420 can be more reliably formed.

In addition, since the first light extracting structure 492 is formed during the growth of the first semiconductor layer 430, a separate etching process may be omitted, thereby reducing the manufacturing cost and manufacturing time of the light emitting device 400. . In addition, damage and damage occurring in an etching process for forming the first light extracting structure 492 may be prevented, thereby improving reliability of the light emitting device 400.

The active layer 450 may be formed on the first semiconductor layer 430. The active layer 450 may be formed of a single or multiple quantum well structure, a quantum-wire structure, a quantum dot structure, or the like using a compound semiconductor material of a group III-V group element.

Well active layer 450 has a composition formula in this case formed of a quantum well structure, for _{example, In x Al y Ga 1 -x-} y N (0 = x = 1, 0 = y = 1, 0 = x + y = 1) It may have a single or quantum well structure having a layer and a barrier layer having a compositional formula of In _a Al _b Ga _{1 -a- b} N (0 = a = 1, 0 = b = 1, 0 = a + b = 1). have. The well layer may be formed of a material having a band gap smaller than the band gap of the barrier layer.

A conductive clad layer (not shown) may be formed on or under the active layer 450. The conductive clad layer (not shown) may be formed of an AlGaN-based semiconductor, and may have a band gap larger than that of the active layer 450.

Meanwhile, an intermediate layer 440 may be formed between the active layer 450 and the first semiconductor layer 430, and the intermediate layer 440 may be injected into the active layer 450 from the second semiconductor layer 460 when a high current is applied. The electron blocking layer may be an electron blocking layer that prevents electrons from flowing back into the first semiconductor layer 430 without recombination in the active layer 450. The intermediate layer (not shown) has a band gap relatively larger than that of the active layer 450, whereby electrons injected from the second semiconductor layer 460 are injected into the first semiconductor layer 430 without being recombined in the active layer 450. The phenomenon can be prevented. Accordingly, the probability of recombination of electrons and holes in the active layer 450 may be increased and leakage current may be prevented.

Meanwhile, the above-described intermediate layer 440 may have a band gap larger than that of the barrier layer included in the active layer 450, and may be formed of a semiconductor layer including Al such as p-type AlGaN, but is not limited thereto. .

The second semiconductor layer 460 may be formed on the active layer 450. The second semiconductor layer 460 may be implemented as an n-type semiconductor layer, and the n-type semiconductor layer may be, for example, In _x Al _y Ga _{1 -xy} N (0 = x = 1, 0 = y = 1, 0 = x semiconductor material having a compositional formula of + y = 1), for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, and the like, for example, n, such as Si, Ge, Sn, Se, Te, etc. Type dopants may be doped.

A second electrode layer 480 electrically connected to the second semiconductor layer 460 may be formed on the second semiconductor layer 460, and the second electrode layer 480 may include at least one pad or an electrode having a predetermined pattern. It may include. The second electrode layer 480 may be disposed in the center region, the outer region, or the corner region of the upper surface of the second semiconductor layer 460, but is not limited thereto. The second electrode layer 480 may be disposed in a region other than the second semiconductor layer 460, but is not limited thereto.

The second electrode layer 480 may be a conductive material such as In, Co, Si, Ge, Au, Pd, Pt, Ru, Re, Mg, Zn, Hf, Ta, Rh, Ir, W, Ti, Ag, Cr It may be formed in a single layer or multiple layers using a metal or an alloy selected from among Mo, Nb, Al, Ni, Cu, and WTi.

The light emitting structure 470 may include a third semiconductor layer (not shown) having a polarity opposite to that of the second semiconductor layer 460 on the second semiconductor layer 460. In addition, the first semiconductor layer 430 may be an n-type semiconductor layer, and the second semiconductor layer 460 may be implemented as a p-type semiconductor layer. Accordingly, the light emitting structure layer 470 may include at least one of an N-P junction, a P-N junction, an N-P-N junction, and a P-N-P junction structure.

Meanwhile, as illustrated in FIG. 6D, a second light extracting structure 494 may be formed on the side surface of the light emitting structure 470.

As described above, since the first growth surface of the nitride semiconductor layer forming the light emitting structure 470 is a nonpolar or semipolar crystal surface, the C-plane {0001} may be formed on the side surface of the light emitting structure 470, and thus Ga-face or N-face of the C-plane {0001} may be formed on the side of the light emitting structure 470.

Ga-face and N-face of the C-plane {0001} can be easily etched through a wet etching process, the side surface of the light emitting structure 470 can be easily etched through a wet etching process, thus the uneven portion A second light extracting structure 494 may be formed on the side surface of the light emitting structure 470.

Meanwhile, as illustrated in FIG. 6E, a third light extracting structure 496 may be formed on the upper surface of the light emitting structure 470.

The third light extracting structure 496 may be formed in a portion or the entire area of the upper surface of the second semiconductor layer 460. The third light extracting structure 496 may be formed by performing etching on at least one region of the upper surface of the second semiconductor layer 460, but is not limited thereto. The etching process may include a wet or / and dry etching process, and as the etching process is performed, an upper surface of the light transmissive electrode layer (not shown) or an upper surface of the second semiconductor layer 460 may be formed on the third light extracting structure 496. Roughness may be included. The roughness may be irregularly formed in a random size, but is not limited thereto. The roughness may be at least one of a texture pattern, a concave-convex pattern, and an uneven pattern, which is an uneven surface.

The roughness may be formed to have various shapes such as a cylinder, a polygonal column, a cone, a polygonal pyramid, a truncated cone, a polygonal pyramid, and the like, preferably including a horn shape.

The third light extracting structure 496 may be formed by a method such as photo electrochemical (PEC), but is not limited thereto. As the third light extracting structure 496 is formed on the upper surface of the transparent second semiconductor layer 460, the light generated from the active layer 450 is formed on the transparent electrode layer (not shown) or the upper portion of the second semiconductor layer 460. Since total reflection from the surface may be prevented from being reabsorbed or scattered, it may contribute to the improvement of light extraction efficiency of the light emitting device 400.

Meanwhile, the second light extracting structure 494 and the third light extracting structure 496 may be formed selectively or overlapping each other, but are not limited thereto.

7 to 9B are views illustrating a manufacturing process of the light emitting device according to the embodiment.

Hereinafter, a manufacturing process of a light emitting device according to an embodiment will be described with reference to FIGS. 7 to 9B.

7 illustrates a step in which a semiconductor layer is grown on a growth substrate 510 to form a light emitting structure 520.

The light emitting structure 520 may be grown by supplying a source on a growth substrate 510 at a predetermined growth pressure and a growth temperature atmosphere. The light emitting structure 520 may be formed of, for example, a nitride semiconductor layer, and may include a first semiconductor layer 522, an active layer 524, and a second semiconductor layer 526.

In addition, the light emitting structure 520 may be grown to have a non-polar growth surface as described above.

Subsequently, as shown in FIG. 8, roughness may be formed on the growth surface of the second semiconductor layer 526, and the roughness may include growth pressure, growth temperature, and source supply conditions at the growth stage of the second semiconductor layer 526. And additive input conditions and the like may be varied, but is not limited thereto.

For example, roughness may be formed by increasing a growth pressure during growth of the second semiconductor layer 526. That is, the growth step of the second semiconductor layer 526 includes a first step having a first growth pressure, and a second step performed after the first step and having a second growth pressure, wherein the second growth pressure is the first growth. It can be higher than the pressure.

Alternatively, for example, roughness may be formed by lowering a growth temperature during growth of the second semiconductor layer 526. That is, the growth step of the second semiconductor layer 526 includes a third step having a first growth temperature, and a fourth step performed after the third step and having a second growth temperature, wherein the second growth temperature is the first growth. It may be lower than the temperature.

 Alternatively, for example, roughness is formed on the growth surface of the second semiconductor layer 526 by varying an input amount of a predetermined additive, such as a surfactant, which makes the growth surface of the nitride semiconductor layer uniform during the growth of the second semiconductor layer 526. It is possible to, but not limited to.

Meanwhile, the source loading condition may vary depending on the growth temperature, the growth pressure, and the predetermined additive loading condition of the second semiconductor layer 526, but is not limited thereto.

Accordingly, a first light extracting structure 530 having a predetermined roughness may be formed on the second semiconductor layer 526, and the first light extracting structure 530 formed on the second semiconductor layer 526 emits light. The light extraction efficiency of the device 500 can be improved.

Since the first light extracting structure 530 may be formed during the growth of the second semiconductor layer 526, a separate etching process for forming the first light extracting structure 530 may be omitted, and thus a light emitting device ( 500) The manufacturing process can be shortened and manufacturing cost can be reduced. In addition, when the etching process is performed, damage that may occur to the light emitting structure 520 may be prevented, thereby improving reliability of the light emitting device 500. In addition, since the first light extraction structure 530 having a compact structure as described above may be formed, the light extraction efficiency and the light emission efficiency of the light emitting device 500 may be improved.

Subsequently, as shown in FIG. 9A, one region of the second semiconductor layer 526 and the active layer 524 is removed, and one region of the first semiconductor layer 522 is exposed, and then the second semiconductor layer 526 is removed. The second electrode 544 may be formed on the first electrode 542, and the first electrode 542 may be formed on the first semiconductor layer 522. In this case, one region of the second semiconductor layer 526 and the active layer 524 may be removed through a predetermined etching process.

Meanwhile, as illustrated in FIG. 9B, the light emitting structure 520 may be etched to form the second light extracting structure 532.

The second light extracting structure 532 may be formed through a wet etching process in which the resultant is immersed in a container containing an etchant such as potassium hydroxide (KOH) or sodium hydroxide (NaOH), but is not limited thereto. .

As described above, the Ga-face or N-face of the C-plane {0001} is formed on the side surface of the light emitting structure 520, and the Ga-face and N-face of the C-plane {0001} are subjected to a wet etching process. Since it can be easily etched, the side surface of the light emitting structure 520 can be easily etched through a wet etching process.

10 to 13C are views illustrating a manufacturing process of the light emitting device according to the embodiment.

In another embodiment, first, the light emitting structure 620 including the first semiconductor layer 622, the active layer 624, and the second semiconductor layer 626 may be grown on the growth substrate 610 as shown in FIG. 10. 11, the first light extracting structure 632 may be formed on the second semiconductor layer 626 during the growth of the second semiconductor layer 626.

As described above, the first light extracting structure 632 may be formed by varying a growth pressure, a growth temperature, a source input condition, and a predetermined additive input condition.

Subsequently, as illustrated in FIG. 12, the support substrate 650 of metal or conductive material may be formed on the first semiconductor layer 622, and the growth substrate 610 may be removed. The support substrate 650 may be formed by a separate sheet and formed by a bonding method, or may be formed by a plating method, a deposition method, or the like, but is not limited thereto. Meanwhile, a first electrode layer 640 may be formed between the support substrate 650 and the first semiconductor layer 622.

Meanwhile, the growth substrate 610 may be removed by at least one of laser lift off or etching, but is not limited thereto.

As the supporting substrate 610 is formed on the second semiconductor layer 626, the first light extracting structure 632 formed on the second semiconductor layer 626 may include the second semiconductor layer 626 and the supporting substrate 640. It can be placed in between. The first light extracting structure 632 formed on the second semiconductor layer 626 may improve light extraction efficiency of the light emitting device 600.

Meanwhile, as illustrated in FIG. 13A, the second electrode layer 660 may be formed on the top surface of the second semiconductor layer 626.

Meanwhile, as illustrated in FIG. 13B, a second light extracting structure 634 may be formed on the side surface of the light emitting structure 620.

The second light extracting structure 634 may be formed through a wet etching process in which the resultant is immersed in a container containing an etchant such as potassium hydroxide (KOH) or sodium hydroxide (NaOH), but is not limited thereto. .

As described above, the Ga-face or N-face of the C-plane {0001} is formed on the side of the light emitting structure 620, the Ga-face and N-face of the C-plane {0001} through a wet etching process Since it may be easily etched, the side surface of the light emitting structure 620 may be easily etched through a wet etching process.

Meanwhile, as illustrated in FIG. 13C, the third light extracting structure 636 may be formed on the upper surface of the light emitting structure 620, and the third light extracting structure 636 may be formed through a predetermined etching process.

The second light extracting structure 634 and the third light extracting structure 636 may be selectively or overlapping with each other, but are not limited thereto.

14A and 14B are a perspective view and a cross-sectional view of a light emitting device package according to an embodiment.

14A and 14B, the light emitting device package 700 includes a body 710 having a cavity 720, first and second lead frames 740 and 750 mounted on the body 710, and a first And a light emitting device 730 electrically connected to the second lead frames 740 and 750, and a resin layer (not shown) formed in the cavity 720 to cover the light emitting device 730.

The body 710 is made of a resin material such as polyphthalamide (PPA), silicon (Si), aluminum (Al), aluminum nitride (AlN), photosensitive glass (PSG), polyamide 9T (PA9T) ), Neo geotactic polystyrene (SPS), a metal material, sapphire (Al ₂ O ₃ ), beryllium oxide (BeO), may be formed of at least one of a printed circuit board (PCB, Printed Circuit Board). The body 710 may be formed by injection molding, etching, or the like, but is not limited thereto.

The inner surface of the body 710 may be formed inclined surface. The angle of reflection of the light emitted from the light emitting device 730 may vary according to the angle of the inclined surface, thereby adjusting the directing angle of the light emitted to the outside.

As the directivity of light decreases, the concentration of light emitted from the light emitting device 730 to the outside increases. On the contrary, the greater the directivity of light, the less the concentration of light emitted from the light emitting device 730 to the outside.

On the other hand, the shape of the cavity 720 formed on the body 710 as viewed from above may be circular, rectangular, polygonal, elliptical, or the like, and may have a curved shape, but is not limited thereto.

The light emitting device 730 is mounted on the first lead frame 740 and may be, for example, a light emitting device emitting light of red, green, blue, white or the like, or a UV (Ultra Violet) light emitting device emitting ultraviolet light. But it is not limited thereto. In addition, one or more light emitting devices 730 may be mounted.

In addition, the light emitting device 730 may be a horizontal type in which all of its electrical terminals are formed on an upper surface, or a vertical type or flip chip formed on an upper and a lower surface. Applicable

On the other hand, the light emitting device 730 according to the embodiment includes a light extraction structure (not shown) including a concave-convex portion having different side inclinations, the light extraction efficiency can be improved, and thus the light emitting efficiency of the light emitting device package 700 This can be improved.

The resin layer (not shown) may be filled in the cavity 720 to cover the light emitting device 730.

The resin layer (not shown) may be formed of silicon, epoxy, and other resin materials, and may be formed by filling the cavity 720 and then UV or heat curing the same.

In addition, the resin layer (not shown) may include a phosphor, and the phosphor may be selected from a wavelength of light emitted from the light emitting device 730 so that the light emitting device package 700 may realize white light.

The phosphor is one of a blue light emitting phosphor, a blue green light emitting phosphor, a green light emitting phosphor, a yellow green light emitting phosphor, a yellow light emitting phosphor, a yellow red light emitting phosphor, an orange light emitting phosphor, and a red light emitting phosphor according to a wavelength of light emitted from the light emitting element 730. Can be applied.

That is, the phosphor may be excited by the light having the first light emitted from the light emitting device 730 to generate the second light. For example, when the light emitting element 730 is a blue light emitting diode and the phosphor is a yellow phosphor, the yellow phosphor may be excited by blue light to emit yellow light, and the blue light and blue light generated by the blue light emitting diode may be used. As the generated yellow light is mixed, the light emitting device package 700 may provide white light.

Similarly, when the light emitting element 730 is a green light emitting diode, a magenta phosphor or a mixture of blue and red phosphors is used. When the light emitting element 730 is a red light emitting diode, a cyan phosphor or a blue and green phosphor is used. For example,

Such a fluorescent material may be a known fluorescent material such as a YAG, TAG, sulfide, silicate, aluminate, nitride, carbide, nitridosilicate, borate, fluoride or phosphate.

The first and second lead frames 740 and 750 are made of a metal material, for example, titanium (Ti), copper (Cu), nickel (Ni), gold (Au), chromium (Cr), and tantalum (Ta). , Platinum (Pt), tin (Sn), silver (Ag), phosphorus (P), aluminum (Al), indium (In), palladium (Pd), cobalt (Co), silicon (Si), germanium (Ge) It may include one or more materials or alloys of hafnium (Hf), ruthenium (Ru), iron (Fe). In addition, the first and second lead frames 740 and 750 may be formed to have a single layer or a multilayer structure, but the embodiment is not limited thereto.

The first second lead frames 740 and 750 are spaced apart from each other and electrically separated from each other. The light emitting device 730 is mounted on the first and second lead frames 740 and 750, and the first and second lead frames 740 and 750 are in direct contact with the light emitting device 730 or a soldering member (not shown). May be electrically connected through a material having conductivity such as C). In addition, the light emitting device 730 may be electrically connected to the first and second lead frames 740 and 750 through wire bonding, but is not limited thereto. Therefore, when power is connected to the first and second lead frames 740 and 750, power may be applied to the light emitting device 730. Meanwhile, several lead frames (not shown) may be mounted in the body 710, and each lead frame (not shown) may be electrically connected to the light emitting device 730, but is not limited thereto.

A plurality of light emitting device packages 700 according to the embodiment may be arranged on a substrate, and a light guide plate, a prism sheet, a diffusion sheet, or the like, which is an optical member, may be disposed on an optical path of the light emitting device package 700. Such a light emitting device package, a substrate, and an optical member can function as a light unit. Another embodiment may be implemented as a display device, an indicator device, or a lighting system including the light emitting device or the light emitting device package described in the above embodiments, and for example, the lighting system may include a lamp or a street lamp.

15A is a perspective view illustrating a lighting apparatus including a light emitting device package according to an embodiment, and FIG. 15B is a cross-sectional view illustrating a C-C 'cross section of the lighting apparatus of FIG. 15A.

15A and 15B, the lighting device 800 may include a body 810, a cover 830 fastened to the body 810, and a closing cap 850 located at both ends of the body 810. have.

The light emitting device module 840 is fastened to the lower surface of the body 810, and the body 810 is conductive so that heat generated in the light emitting device package 844 may be discharged to the outside through the upper surface of the body 810. And it may be formed of a metal material having an excellent heat dissipation effect.

The light emitting device package 844 may be mounted on the PCB 842 in multiple colors and in multiple rows to form an array. The light emitting device package 844 may be mounted at the same interval or may be mounted with various separation distances as necessary to adjust brightness. As the PCB 842, a metal core PCB (MPPCB) or a PCB made of FR4 may be used.

Meanwhile, the light emitting device package 844 according to the embodiment includes a light emitting device (not shown), and the light emitting device (not shown) includes a light extraction structure (not shown) including an uneven portion having different side slopes, Since the extraction efficiency may be improved, the luminous efficiency of the light emitting device package 844 and the lighting device 800 may be improved.

The cover 830 may be formed in a circular shape to surround the lower surface of the body 810, but is not limited thereto.

The cover 830 protects the light emitting device module 840 from the foreign matter and the like. In addition, the cover 830 may include diffusing particles to prevent glare of the light generated from the light emitting device package 844 and to uniformly emit light to the outside, and may further include at least one of an inner surface and an outer surface of the cover 830. A prism pattern or the like may be formed on either side. In addition, a phosphor may be applied to at least one of an inner surface and an outer surface of the cover 830.

On the other hand, since the light generated from the light emitting device package 844 is emitted to the outside through the cover 830, the cover 830 should have excellent light transmittance, and has sufficient heat resistance to withstand the heat generated by the light emitting device package 844. The cover 830 is preferably formed of a material including polyethylene terephthalate (PET), polycarbonate (PC), polymethyl methacrylate (PMMA), or the like. .

Closing cap 850 is located at both ends of the body 810 may be used for sealing the power supply (not shown). In addition, the closing cap 850 is formed with a power pin 852, the lighting device 800 according to the embodiment can be used immediately without a separate device to the terminal from which the existing fluorescent lamps are removed.

16 is an exploded perspective view of a liquid crystal display including the light emitting device according to the embodiment.

FIG. 16 illustrates an edge-light method, and the liquid crystal display 900 may include a liquid crystal display panel 910 and a backlight unit 970 for providing light to the liquid crystal display panel 910.

The liquid crystal display panel 910 may display an image using light provided from the backlight unit 970. The liquid crystal display panel 910 may include a color filter substrate 912 and a thin film transistor substrate 914 facing each other with the liquid crystal interposed therebetween.

The color filter substrate 912 may implement a color of an image displayed through the liquid crystal display panel 910.

The thin film transistor substrate 914 is electrically connected to the printed circuit board 918 on which a plurality of circuit components are mounted through the driving film 917. The thin film transistor substrate 914 may apply a driving voltage provided from the printed circuit board 918 to the liquid crystal in response to a driving signal provided from the printed circuit board 918.

The thin film transistor substrate 914 may include a thin film transistor and a pixel electrode formed of a thin film on another substrate of a transparent material such as glass or plastic.

The backlight unit 970 may convert the light provided from the light emitting device module 920, the light emitting device module 920 into a surface light source, and provide the light guide plate 930 and the light guide plate to the liquid crystal display panel 910. Reflective sheet reflecting the light emitted to the light guide plate 930 to the plurality of films 950, 966, 964 and the light guide plate 930 to uniform the luminance distribution of the light provided from the 930 and to improve the vertical incidence ( 947).

The light emitting device module 920 may include a PCB substrate 922 such that a plurality of light emitting device packages 924 and a plurality of light emitting device packages 924 are mounted to form an array.

Meanwhile, the light emitting device package 9224 according to the embodiment includes a light emitting device (not shown), and the light emitting device (not shown) includes a light extraction structure (not shown) including an uneven portion having different side slopes, Since the extraction efficiency may be improved, the light emission efficiency of the light emitting device package 924 and the backlight unit 970 may be improved.

The backlight unit 970 includes a diffusion film 966 for diffusing light incident from the light guide plate 930 toward the liquid crystal display panel 910, and a prism film 950 for condensing the diffused light to improve vertical incidence. ), And may include a protective film 964 for protecting the prism film 950.

17 is an exploded perspective view of a liquid crystal display including the light emitting device according to the embodiment. However, the parts illustrated and described in FIG. 16 will not be repeatedly described in detail.

17 illustrates a direct method, the liquid crystal display 1000 may include a liquid crystal display panel 1010 and a backlight unit 1070 for providing light to the liquid crystal display panel 1010.

Since the liquid crystal display panel 1010 is the same as that described with reference to FIG. 16, a detailed description thereof will be omitted.

The backlight unit 1070 may include a plurality of light emitting device modules 1023, a reflective sheet 1024, a lower chassis 1030 in which the light emitting device modules 1023 and the reflective sheet 1024 are accommodated, and an upper portion of the light emitting device module 1023. It may include a diffusion plate 1040 and a plurality of optical film 1060 disposed in the.

LED Module 1023 A plurality of light emitting device packages 1022 and a plurality of light emitting device packages 1022 may be mounted to include a PCB substrate 1021 to form an array.

Meanwhile, the light emitting device package 1022 according to the embodiment includes a light emitting device (not shown), and the light emitting device (not shown) includes a light extraction structure (not shown) including an uneven portion having different side slopes, Since the extraction efficiency may be improved, the light emission efficiency of the light emitting device package 1022 and the backlight unit 1070 may be improved.

The reflective sheet 1024 reflects the light generated from the light emitting device package 1022 in the direction in which the liquid crystal display panel 1010 is positioned to improve light utilization efficiency.

Meanwhile, the light generated by the light emitting device module 1023 is incident on the diffuser plate 1040, and the optical film 1060 is disposed on the diffuser plate 1040. The optical film 1060 may include a diffuser film 1066, a prism film 1050, and a protective film 1064.

Meanwhile, the light emitting device according to the embodiment is not limited to the configuration and method of the embodiments described above, but the embodiments may be modified so that all or some of the embodiments may be selectively And may be configured in combination.

In addition, while the preferred embodiments have been shown and described, the present invention is not limited to the specific embodiments described above, and the present invention is not limited to the specific embodiments described above, and the present invention may be used in the art without departing from the gist of the invention as claimed in the claims. Various modifications can be made by those skilled in the art, and these modifications should not be individually understood from the technical spirit or the prospect of the present invention.

300 light emitting element 310 support substrate
320: first semiconductor layer 330: active layer
340: intermediate layer 350: second semiconductor layer
360: light emitting structure 380: first light extraction structure

Claims (18)

A light emitting structure including a first semiconductor layer, a second semiconductor layer, and an active layer formed between the first semiconductor layer and the second semiconductor layer; And
And a first light extracting structure formed on the first growth surface of the light emitting structure.
The first light extraction structure includes a plurality of uneven parts,
The side cross section of the uneven part is
A light emitting device that forms an effervescent triangle having different inclinations on both sides. The method of claim 1,
The first growth surface is
A light emitting device comprising at least one of a nonpolar crystal plane and a semipolar crystal plane. The method of claim 2,
The first growth surface is any one of the A-plane {11-20}, R-plane {1102}, M-plane {1-100} The method of claim 1,
The slope of the side,
Light emitting device 30 to 60 degrees. The method of claim 1,
The height of the uneven portion,
100 nm to 500 nm light emitting device. The method of claim 5,
The width of the uneven portion,
Light emitting device is 1.5 times to 1.8 times the height of the uneven portion. The method of claim 1,
The uneven portion,
Light emitting device formed to have a number of 4 to 10 per 1 um ² . The method of claim 1,
And a support substrate formed on the first semiconductor layer and the second semiconductor layer. The method of claim 1,
And a second light extracting structure formed on a side of the light emitting structure. 10. The method of claim 9,
The light emitting structure is formed of a nitride semiconductor layer,
The nitride semiconductor layer includes a C-plane {0001},
The second light extraction structure,
A light emitting device formed on the C-plane {0001}. The method of claim 10,
The second light extraction structure,
A light emitting device formed on the Ga-face or N-face of the nitride semiconductor layer. The method of claim 1,
And a third light extracting structure formed on an upper surface of the light emitting structure. Preparing a growth substrate;
A second step of growing a nitride semiconductor layer on the growth substrate,
The second step comprises:
Growing a first semiconductor layer on the growth substrate;
A fourth step of growing an active layer on the first semiconductor layer; And
And a fifth step of growing a second semiconductor layer on the active layer.
The fifth step,
A sixth step and a seventh step,
The sixth and seventh steps,
A light emitting device manufacturing method in which at least one of a growth temperature, a growth pressure, an additive amount, and a source amount is different from each other. The method of claim 13.
The sixth step has a first growth temperature, and the seventh step has a second growth temperature,
And the second growth temperature is lower than the first growth temperature. The method of claim 13,
The sixth step has a first growth pressure, and the seventh step has a second growth pressure,
And the second growth pressure is higher than the first growth pressure. The method of claim 13,
The nitride semiconductor layer includes a first growth surface, and the growth substrate includes a second growth surface,
The first growth surface and the second growth surface is a light emitting device manufacturing method of any one of a non-polar crystal surface and a semi-polar crystal surface. 17. The method of claim 16,
The first growth surface is any one of the A-plane {11-20}, R-plane {1102}, M-plane {1-100}. 17. The method of claim 16,
The second growth surface is any one of the A-plane {11-20}, R-plane {1102}, M-plane {1-100}.

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