KR20140025901A - Light emitting device - Google Patents

Abstract

An embodiment of the present invention is to provide a light emitting device which comprises: a light emitting structure having a first semiconductor layer, a second semiconductor layer. and an activating layer between the first semiconductor layer and the second semiconductor layer; a first electrode electrically connected to the first semiconductor layer; a second electrode electrically connected to the second semiconductor layer; and an optical conversion layer disposed to have a predetermined pattern on the first semiconductor layer and conversing a wavelength of the light emitted from the activating layer, wherein the optical conversion layer includes: a first optical conversion layer disposed on one side of the first electrode and having a first optical conversion particle with a first size; and a second optical conversion layer disposed on one side of the first optical conversion layer and having a second optical conversion particle with a second size.

Description

[0001]

An embodiment relates to a light emitting element.

BACKGROUND ART Light emitting devices such as a light emitting diode (LD) or a laser diode using semiconductor materials of Group 3-5 or 2-6 group semiconductors are widely used for various colors such as red, green, blue, and ultraviolet And it is possible to realize a white light beam having high efficiency by using a fluorescent material or combining colors.

Such a light emitting device has advantages such as low power consumption, semi-permanent lifetime, quick response speed, safety, and environmental friendliness compared to conventional light sources such as fluorescent lamps and incandescent lamps, It is important to increase the efficiency of the light emitting device as the brightness required for a lamp used in daily life and a light for a structural signal is increased.

The embodiment provides a light emitting device that improves a light flux and can easily increase a directivity angle.

A light emitting device according to an embodiment includes a first semiconductor layer, a second semiconductor layer, a light emitting structure including an active layer between the first and second semiconductor layers, a first electrode electrically connected to the first semiconductor layer, A second electrode electrically connected to the semiconductor layer; and a light conversion layer disposed on the first semiconductor layer in a predetermined pattern, the light conversion layer converting a wavelength of light emitted from the active layer, A first photo-conversion layer located on one side of the electrode and including first photo-conversion particles having a first size, and second photo-conversion particles positioned on one side of the first photo-conversion layer and having a second size, The second light conversion layer may include a second light conversion layer.

The light emitting device according to the embodiment improves the light flux to the first light conversion layer including the first light conversion particles having a first size adjacent to the periphery of the first electrode disposed on the light emitting structure, And a second light conversion layer including second light conversion particles having a second size different from the first size adjacent to the periphery of the layer.

The light emitting device according to the embodiment includes the photo-conversion particles having different sizes, so that the color conversion efficiency can be improved.

The light emitting device according to the embodiment can minimize the defect due to the pressure applied to the light emitting structure by adjusting the thickness of the second light conversion layer.

1 is a cross-sectional view illustrating a light emitting device according to a first embodiment.
FIG. 1A is a graph showing a change in the directional angle characteristic depending on the size of the photoconversion particle.
2 is a cross-sectional view illustrating a light emitting device according to a second embodiment.
3 is a cross-sectional view illustrating a light emitting device package including the light emitting device according to the embodiment.
4 is a perspective view illustrating a lighting device including a light emitting device module according to an embodiment.
5 is a cross-sectional view taken along the line C-C 'of the illumination device of FIG.
6 is an exploded perspective view of a liquid crystal display device including an optical sheet according to an embodiment.
7 is an exploded perspective view of a liquid crystal display device including an optical sheet according to an embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the invention to those skilled in the art. To fully disclose the scope of the invention to a person skilled in the art, and the invention is only defined by the scope of the claims. Thus, in some embodiments, well known process steps, well known device structures, and well-known techniques are not specifically described to avoid an undesirable interpretation of the present invention. Like reference numerals refer to like elements throughout the specification.

The terms spatially relative, "below", "beneath", "lower", "above", "upper" May be used to readily describe a device or a relationship of components to other devices or components. Spatially relative terms should be understood to include, in addition to the orientation shown in the drawings, terms that include different orientations of the device during use or operation. For example, when inverting an element shown in the figures, an element described as "below" or "beneath" of another element may be placed "above" another element. Thus, the exemplary term "below" can include both downward and upward directions. The elements can also be oriented in different directions, so that spatially relative terms can be interpreted according to orientation.

The terminology used herein is for the purpose of illustrating embodiments and is not intended to be limiting of the present invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. It is noted that the terms "comprises" and / or "comprising" used in the specification are intended to be inclusive in a manner similar to the components, steps, operations, and / Or additions.

Unless defined otherwise, all terms (including technical and scientific terms) used herein may be used in a sense commonly understood by one of ordinary skill in the art to which this invention belongs. Also, commonly used predefined terms are not ideally or excessively interpreted unless explicitly defined otherwise.

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.

Further, the angle and direction mentioned in the description of the structure of the light emitting device in the embodiment are based on those shown in the drawings. In the description of the structure of the light emitting device in the specification, reference points and positional relationship with respect to angles are not explicitly referred to, refer to the related drawings.

1 is a cross-sectional view illustrating a light emitting device according to a first embodiment.

1, a light emitting device 100 includes a first semiconductor layer 162, a second semiconductor layer 166, and first and second semiconductor layers 162 and 166 on a substrate 110 and a substrate 110, And a light emitting structure 160 including an active layer 164 therebetween.

The light emitting device 100 according to the embodiment includes a substrate 110, a coupling layer 120 disposed on the substrate 110, a capping layer 130 disposed on the coupling layer 120, A light emitting structure 160 may be formed on the first electrode 140 and the first electrode 140 and a second electrode 170 may be formed on the light emitting structure 160.

In the embodiment, the light emitting device 100 is a vertical type light emitting device in which electrodes are arranged vertically. However, it is also possible to etch one region of the light emitting structure 160, And may be a lateral type light emitting device, but is not limited thereto.

The substrate 110 may be disposed under the light emitting structure 160 to support the light emitting structure 160 and may have a light transmitting property.

At this time, the substrate 110 may have a light transmitting property by using a light transmitting material or by forming a predetermined material to a predetermined thickness or less, but the present invention is not limited thereto. The refractive index of the substrate 110 may be smaller than the refractive index of the first semiconductor layer 162 for light extraction efficiency, but is not limited thereto.

The substrate 110 may be formed of a semiconductor material. For example, the semiconductor material may be selected from the group consisting of silicon (Si), germanium (Ge), gallium arsenide (GaAs), zinc oxide (ZnO), silicon carbide (SiC), silicon germanium (SiGe), gallium nitride III < / RTI > oxide (Ga2O3).

The substrate 110 may be formed of a conductive material. For example, when the substrate 110 is formed of a metal, the substrate 110 may include at least one selected from the group consisting of gold (Au), nickel (Ni), tungsten (W), molybdenum (Mo), copper (Cu), aluminum (Al), tantalum (Ag), platinum (Pt), and chromium (Cr), or may be formed of two or more alloys, and two or more of the above materials may be laminated. And the thermal stability of the light emitting device 100 can be improved.

The substrate 110 may be formed using a material having excellent thermal conductivity, or may be formed of a conductive material, and may be formed using a metal material or a conductive ceramic. The substrate 110 may be formed of a single layer, and may be formed of a dual structure or a multiple structure.

A bonding layer 120 may be disposed on the substrate 110 for coupling the substrate 110 and the capping layer 130. The bonding layer 120 may be formed from a group consisting of, for example, Au, Sn, In, Ag, Ni, Nb and Cu. The material to be selected or an alloy thereof.

A capping layer 130 may be formed on the bonding layer 120. The capping layer 130 may have a groove (not shown) in which the first electrode 140 is disposed, but is not limited thereto.

That is, the capping layer 130 can determine the disposing position of the first electrode 140 and prevent the first electrode 140 from moving relative to the reflective electrode 142.

The first electrode 140 may include a reflective electrode 142 and a reflective electrode 142 disposed in the groove formed in the capping layer 130 and a transparent electrode 146 disposed on the capping layer 130 .

The reflective electrode 142 may be formed of a material having excellent reflection characteristics such as silver (Ag), nickel (Ni), aluminum (Al), rubidium (Rh), palladium (Pd), iridium (Ir) ), Magnesium (Mg), zinc (Zn), platinum (Pt), gold (Au), hafnium (Hf), and combinations thereof. The transparent electrode 146 may be formed, IZO (indium zinc oxide), IZTO (indium zinc oxide), IZO (indium aluminum zinc oxide), IGZO (indium gallium zinc oxide), IGTO (indium gallium tin oxide), AZO tin oxide, and combinations thereof. However, the present invention is not limited thereto.

The first electrode 140 may have a multilayer structure of the reflective electrode 142 and the transparent electrode 146. For example, the first electrode 140 may be formed of IZO / Ni, AZO / Ag, IZO / Ag / Ni, Ni or the like.

A channel layer 150 may be formed on a side surface of the first electrode 140 and a light emitting structure 160 may be disposed on the first electrode 140.

The light emitting structure 160 may include the active layer 164 between the first semiconductor layer 162, the second semiconductor layer 166 and the first and second semiconductor layers 162 and 166 as described above.

The first semiconductor layer 162 may be a p-type semiconductor layer injecting holes into the active layer 164 and the first semiconductor layer 162 may be formed in the active layer 164 in a blue color having a wavelength of about 400 to 550 nm Blue) light, a semiconductor material having a composition formula of InxAlyGa1-x-yN (0? X? 1, 0? Y? 1, 0? X + y? 1), for example GaP (Gallium nitride) Aluminum nitride (AlN), aluminum gallium nitride (AlGaN), indium gallium nitride (InGaN), indium nitride (InN), InAlGaN and AlInN. The first semiconductor layer 162 may be doped with a p-type dopant such as magnesium (Mg), zinc (Zn), calcium (Ca), strontium (Sr), barium (Ba)

When the active layer 164 generates red light having a wavelength of about 610 to 780 nm, the first semiconductor layer 162 may be formed of InxAlyGa1-x-yP (0? X? 1, 0? Y? 0? X + y? 1). For example, the first semiconductor layer 162 may be formed of GaP or AlGaInP, but is not limited thereto. The first semiconductor layer 162 may be doped with a p-type dopant such as magnesium (Mg), zinc (Zn), calcium (Ca), strontium (Sr), barium (Ba)

The active layer 164 may be formed on the first semiconductor layer 162. The active layer 164 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 Group 3-V group elements.

When the wavelength of the generated light is blue, the active layer 264, which is a quantum well structure, has a composition formula of InxAlyGa1-x-yN (0? X? 1, 0? Y? 1, 0? X + And a single or quantum well structure having a barrier layer having a composition formula of InaAlbGa1-a-bN (0? A? 1, 0? B? 1, 0? A + b? 1). The well layer may be formed of a material having an energy band gap smaller than the energy band gap of the barrier layer.

When the wavelength of the generated light is red, the active layer 264 as a quantum well structure has a composition formula of InxAlyGa1-x-yP (0? X? 1, 0? Y? 1, 0? X + y? 1) A well layer and a barrier layer having a composition formula of InaAlbGa1-a-bP (0? A? 1, 0? B? 1, 0? A + b? 1). The well layer may be formed of a material having an energy band gap smaller than the energy band gap of the barrier layer.

The second semiconductor layer 166 may be implemented as an n-type semiconductor layer.

For example, when the wavelength of light generated by the active layer 164 is blue, the second semiconductor layer 166 may be formed of InxAlyGa1-x-yN (0? X? 1, 0? Y? (AlN), AlGaN (Indium Gallium Nitride), InGaN (Indium Gallium nitride), InN (Indium nitride), InAlGaN, AlInN or the like having a composition formula of GaN Can be selected. The second semiconductor layer 166 may be doped with an n-type dopant such as silicon (Si), germanium (Ge), tin (Sn), selenium (Se), or tellurium (Te).

For example, when the wavelength of light generated by the active layer 164 is red, the second semiconductor layer 166 may be formed of InxAlyGa1-x-yP (0? X? 1, 0? Y? Lt; = 1), but the present invention is not limited thereto. For example, the first semiconductor layer 162 may be formed of GaP or AlGaInP, but is not limited thereto. The second semiconductor layer 166 may be doped with an n-type dopant such as silicon (Si), germanium (Ge), tin (Sn), selenium (Se), or tellurium (Te).

The light emitting structure 160 may include a third conductive semiconductor layer (not shown) having a polarity opposite to that of the second semiconductor layer 166 on the second semiconductor layer 166. Also, the first semiconductor layer 162 may be an n-type semiconductor layer and the second semiconductor layer 166 may be a p-type semiconductor layer. Accordingly, the light emitting structure 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.

The second semiconductor layer 166 may have irregularities (pss) in one region of its upper surface. The second semiconductor layer 166 may be etched in at least one region of the upper surface to form irregularities. The etching process may include a wet or dry etching process. The etched surface on which the etching of the second semiconductor layer 166 is performed may be an N (nitride) -face that is easily etched by wet etching, and the surface roughness may be improved compared to Ga (gallium) -face. As the etching process is performed, the upper surface of the second semiconductor layer 166 may be formed with irregularities that form a light extracting structure. The irregularities on the upper surface of the second semiconductor layer 166 may be irregularly formed in a random size, but the present invention is not limited thereto. The irregularities pss on the upper surface of the second semiconductor layer 166 may include at least one of a texture pattern, a concavo-convex pattern, and an uneven pattern, but the present invention is not limited thereto.

The concavo-convex (pss) of the second semiconductor layer 166 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, No.

The projections and depressions pss on the second semiconductor layer 166 may be formed at a period shorter than the wavelength of light generated in the active layer 164. For example, if the light generated in the active layer 164 is a red region of 620 to 700 nm, the period of the irregularities (pss) of the second semiconductor layer 166 may be 620 nm or less. If the light generated in the active layer 164 is a wave region of 450 to 480 nm, the period of the concavity and convexity of the second semiconductor layer 166 may be 450 nm or less.

The second semiconductor layer 166 may have a concavo-convex structure formed on the upper surface thereof so that the effective refractive index of the upper surface of the second semiconductor layer 166 may be smaller than that of the second semiconductor layer 166 itself, have.

The irregularities (pss) of the second semiconductor layer 166 may be formed by a wet etching method using a photoelectrochemical (PEC) or a KOH solution, but are not limited thereto.

The second semiconductor layer 166 is formed on the top of the second semiconductor layer 166 so that the light generated in the active layer 164 is totally reflected and reabsorbed or scattered within the light emitting structure 160 can be minimized. The second semiconductor layer 166 may have irregularities (pss) formed thereon to improve light extraction efficiency.

A second electrode 170 may be disposed on the second semiconductor layer 166 and the second electrode 170 may include at least one pad (not shown) and / or an electrode having a predetermined pattern, Not limited.

The second electrode 170 may be disposed in the center region, the outer region, or the edge region of the upper surface of the second semiconductor layer 166, but the present invention is not limited thereto. The second electrode 170 may be connected to at least one branch electrode (not shown) connected to a pad (not shown) and a pad (not shown) and extending in at least one direction. The second electrode 170 may be disposed on another region of the second semiconductor layer 166, but the present invention is not limited thereto.

The second electrode 170 may be formed of a conductive material such as indium (In), tungsten (Co), silicon (Si), germanium (Ge), gold (Au), palladium (Pd), platinum (Ru), rhenium (Re), magnesium (Mg), zinc (Zn), hafnium (Hf), tantalum (Ta), rhodium (Rh), iridium (Ir), tungsten A metal or an alloy selected from Ag, Cr, Mo, Nb, Al, Ni, Cu, and WTi, Or may be formed as a single layer or multiple layers.

On the other hand, the second electrode 170 may be disposed on the flat top surface of the second semiconductor layer 166 and may be disposed on uneven surfaces (pss), but is not limited thereto.

A protective layer 180 may be formed on the side surface and the top surface of the light emitting structure 160.

The protective layer 180 is formed on the concavo-convex portion (pss) of the second semiconductor layer 166, but may be formed only on the side surface of the light emitting structure 160, but is not limited thereto.

The protective layer 180 may have a high light transmittance and may be formed of an insulating material, for example, SiO 2, SiO x, SiO x N y, Si 3 N 4, or Al 2 O 3.

A light conversion layer 190 may be formed on the passivation layer 180 to convert the wavelength of the light emitted from the active layer 164.

The photo-conversion layer 190 may be located on one side of the second electrode 170. For example, the photo-conversion layer 190 surrounds the second electrode 170 and may be formed on the upper surface of the passivation layer 180, that is, the second semiconductor layer 166.

The photo-conversion layer 190 is disposed adjacent to the side of the second electrode 170 and includes a first photo-conversion layer 192 including first photo-conversion particles a1 having a first size d1, And a second photo-conversion layer 194 located on one side of the first photo-conversion layer 192 and including second photo-conversion particles a2 having a second size d2. The second light conversion layer 194 may be formed to surround the first light conversion layer 192, for example.

In the embodiment, the first and second light conversion layers 192 and 194 are described as being the same phosphor (not shown) that converts the light emitted from the active layer 164 into light of the same wavelength. However, And may be different phosphors to be converted, but is not limited thereto.

That is, the first size d1 of the first photo-conversion particles a1 included in the first photo-conversion layer 192 may be between 5 μm and 7 μm. The second size d2 of the second light conversion particles a2 included in the second light conversion layer 194 may be 15 mu m to 30 mu m.

When the first size d1 is less than 5 mu m, the degree of increase of the light flux may be small although the directivity angle is widened. When the first size d1 is more than 7 mu m, the degree of increase of the light flux may be improved, The effect can be small.

If the second size d2 is less than 15 mu m, the light flux is lowered and the directivity angle may be increased. When the second size d2 is larger than 30 mu m, the light flux is increased but the directivity angle is very low.

Table 1 below shows the experimental fluorescence obtained by examining the luminous flux and the color temperature according to the particle size.

[Table 1]

In Table 1, LM denotes a lumen, C _x and C _y denote color coordinates, CCT denotes a color temperature, and CRI denotes a color rendering index. In Table 1, the size of the large particles is 15 占 퐉 to 50 占 퐉, the sizes of the middle particles are 8 占 퐉 to 13 占 퐉, and the sizes of the small particles are 5 占 퐉 to 7 占 퐉.

Referring to Table 1, it can be seen that the light flux increases as the size of the photoconversion particle increases.

FIG. 1A is a graph showing a change in the orientation angle characteristic of the light emitting device according to the size of the light conversion particles. In Fig. 1A, the size of the large particles is 15 mu m to 50 mu m, the size of the medium particles is 8 mu m to 13 mu m, and the size of the small particles is 5 mu m to 7 mu m.

Referring to FIG. 1A, the larger the size of the photo-converted particles, the higher the color temperature, but the smaller the orientation angle.

The thickness of the second light conversion layer 194 may be between 40 μm and 100 μm.

When the thickness b2 of the second light conversion layer 194 is thinner than 40 占 퐉, defects due to pressure can be generated in the light emitting structure 160 during the process for reducing the thickness. When the thickness b2 is thicker than 100 占 퐉, It is difficult to uniformize the thickness of the second light conversion layer 194 on the light emitting device 100, and the light conversion efficiency of the light emitting device 100 may deteriorate.

1, the thickness b1 of the first light conversion layer 192 is shown to be thinner than the thickness b2 of the second light conversion layer 194, but there may be various embodiments not limited thereto.

The first photoconversion layer 192 and the second photoconversion layer 194 include photoconversion particles having different sizes to increase the luminous flux of the light emitted from the light emitting structure 160, It is possible to widen the directivity angle.

Accordingly, the light conversion layer 190 can broaden the directivity angle of the light emitting device 100 as a whole, so that it is easy to secure the directivity angle and the light flux.

2 is a cross-sectional view illustrating a light emitting device according to a second embodiment.

The light-emitting device 200 shown in Fig. 2 will not be described or briefly explained in the same manner as the light-emitting device 100 shown in Fig.

2, the light emitting device 200 includes a substrate 210, a first semiconductor layer 262, a second semiconductor layer 266, and first and second semiconductor layers 262 and 266 on the substrate 210, The light emitting structure 260 including the active layer 264 and the light converting layer 290 on the light emitting structure 260 may be included.

The light conversion layer 290 may surround the second electrode 270 and may have a predetermined pattern.

That is, the light conversion layer 290 includes a first light conversion layer 292 including first light conversion particles a1 having a first size d1 with respect to the second electrode 270, And a second photoconversion layer 294 comprising a second photoconversion particle a2 adjacent the layer 292 and having a second size d2.

In the second embodiment, the first and second light conversion layers 292 and 294 may be sequentially formed on the light conversion layer 290.

That is, the first light conversion layer 292 may increase the light flux through a portion disposed between the portion surrounding the second electrode 270 and the second light conversion layer 294.

Here, the first and second light conversion layers 292 and 294 may be formed concentrically with respect to the second electrode 270, or may have a different shape, but are not limited thereto .

Also, although not shown in the drawing, any one of the first and second light conversion layers 292 and 294 may be formed on the other layer and may also be formed on the second electrode 270, Do not limit.

The first size d1 of the first photo-conversion particles a1 included in the first photo-conversion layer 292 may be 5 탆 to 7 탆. The second size d2 of the second light conversion particles a2 included in the second light conversion layer 194 may be 15 mu m to 30 mu m.

When the first size d1 is less than 5 mu m, the degree of increase of the light flux may be small although the directivity angle is widened. When the first size d1 is more than 7 mu m, the degree of increase of the light flux may be improved, The effect can be small.

If the second size d2 is less than 15 mu m, the light flux is lowered and the directivity angle may be increased. When the second size d2 is larger than 30 mu m, the light flux is increased but the directivity angle is very low.

The thickness of the second light conversion layer 294 may be between 40 μm and 100 μm.

When the thickness b2 of the second light conversion layer 294 is thinner than 40 占 퐉, defects due to pressure can be generated in the light emitting structure 260 during the process for reducing the thickness. When the thickness b2 is thicker than 100 占 퐉, It is difficult to uniformize the thickness of the second light conversion layer 294 on the light emitting device 200, and the light conversion efficiency of the light emitting device 200 may be reduced.

2, the thickness b1 of the first photo-conversion layer 292 is shown to be thinner than the thickness b2 of the second photo-conversion layer 294, but there may be various embodiments not limited thereto.

The first and second photo-conversion layers 292 and 294 include photo-conversion particles of different sizes to increase the light flux of the light emitted from the light emitting structure 260, It is possible to widen the directivity angle.

Therefore, the light conversion layer 290 can broaden the directivity angle of the light emitting device 200 as a whole, so that it is easy to secure the directivity angle and the light flux.

3 is a cross-sectional view illustrating a light emitting device package including the light emitting device according to the embodiment.

3, the light emitting device package 300 includes a body 310 having a cavity, a light source 320 mounted on a cavity of the body 310, and an encapsulant 350 filled in the cavity 310 can do.

The body 310 may be made of a resin material such as polyphthalamide (PPA), silicon (Si), aluminum (Al), aluminum nitride (AlN), photo sensitive glass (PSG), polyamide 9T (SPS), a metal material, sapphire (Al2O3), beryllium oxide (BeO), a printed circuit board (PCB), and ceramics. The body 310 may be formed by injection molding, etching, or the like, but is not limited thereto.

The light source unit 320 may be mounted on the bottom surface of the body 310. For example, the light source unit 320 may be any one of the light emitting devices illustrated in FIGS. The light emitting device may be, for example, a colored light emitting device that emits light such as red, green, blue, or white, or a UV (Ultra Violet) light emitting device that emits ultraviolet light. In addition, one or more light emitting elements can be mounted.

The body 310 may include a first electrode 330 and a second electrode 340. The first electrode 330 and the second electrode 340 may be electrically connected to the light source 320 to supply power to the light source 320.

In addition, the first electrode 330 and the second electrode 340 are electrically separated from each other. The first electrode 330 and the second electrode 340 can reflect the light generated from the light source unit 320 to increase the light efficiency. Further, To the outside.

3 illustrates that both the first electrode 330 and the second electrode 340 are bonded to the light source 320 by the wire 360. However, the present invention is not limited thereto, Any one of the electrode 330 and the second electrode 340 may be bonded to the light source 320 by the wire 360 and may be electrically connected to the light source 320 without the wire 360 by the flip- have.

The first electrode 330 and the second electrode 340 may be formed of a metal material such as titanium (Ti), copper (Cu), nickel (Ni), gold (Au), chromium (Cr), tantalum Ta, Pt, Sn, Ag, P, Al, Pd, Co, Si, Ge, Ge), hafnium (Hf), ruthenium (Ru), and iron (Fe). The first electrode 330 and the second electrode 340 may have a single-layer structure or a multi-layer structure, but the present invention is not limited thereto.

The encapsulant 350 may be filled in the cavity and may include a phosphor (not shown). The encapsulant 350 may be formed of a transparent silicone, epoxy, or other resin material, and may be formed in such a manner that the encapsulant 350 is filled in the cavity and then cured by UV or thermal curing.

The phosphor (not shown) may be selected according to the wavelength of the light emitted from the light source unit 320 so that the light emitting device package 300 may emit white light.

The fluorescent material (not shown) included in the encapsulant 350 may be a blue light emitting phosphor, a blue light emitting fluorescent material, a green light emitting fluorescent material, a yellow green light emitting fluorescent material, a yellow light emitting fluorescent material, , An orange light-emitting fluorescent substance, and a red light-emitting fluorescent substance may be applied.

That is, the phosphor (not shown) may be excited by the light having the first light emitted from the light source 320 to generate the second light. For example, when the light source 320 is a blue light emitting diode and the phosphor (not shown) is a yellow phosphor, the yellow phosphor may be excited by blue light to emit yellow light, and blue light emitted from the blue light emitting diode and blue The light emitting device package 300 can provide white light as yellow light generated by excitation by light is mixed.

FIG. 4 is a perspective view illustrating a lighting device including a light emitting device module according to an embodiment, and FIG. 5 is a cross-sectional view illustrating a C-C 'cross section of the lighting device of FIG.

5 is a cross-sectional view of the lighting apparatus 400 of FIG. 4 cut in the longitudinal direction Z and the height direction X and viewed in the horizontal direction Y. FIG.

4 and 5, the lighting apparatus 400 may include a body 410, a cover 430 to be coupled to the body 410, and a finishing cap 450 positioned at both ends of the body 410 have.

The light emitting device module 440 is coupled to a lower surface of the body 410. The body 410 is electrically connected to the light emitting device package 444 through a conductive material such that heat generated from the light emitting device package 444 can be emitted to the outside through the upper surface of the body 410. [ And may be formed of a metal material having excellent heat dissipation effect, but is not limited thereto.

Particularly, the light emitting device module 440 includes a sealing portion (not shown) that surrounds the light emitting device package 444 to prevent foreign matter from penetrating, thereby improving the reliability. In addition, . ≪ / RTI >

The light emitting device package 444 may be mounted on the substrate 442 in a multi-color, multi-row manner to form a module. The light emitting device package 444 may be mounted at equal intervals or may be mounted with various spacings as needed. As such a substrate 442, MCPCB (Metal Core PCB) or FR4 PCB can be used.

The cover 430 may be formed in a circular shape so as to surround the lower surface of the body 410, but is not limited thereto.

The cover 430 protects the internal light emitting device module 440 from foreign substances or the like. The cover 430 may include diffusion particles to prevent glare of the light generated in the light emitting device package 444 and uniformly emit light to the outside and may include at least one of an inner surface and an outer surface of the cover 430 A prism pattern or the like may be formed on one side. Further, the phosphor may be coated on at least one of the inner surface and the outer surface of the cover 430.

Since the light generated from the light emitting device package 444 is emitted to the outside through the cover 430, the cover 430 must have a high light transmittance and sufficient to withstand the heat generated from the light emitting device package 444. [ The cover 430 may be formed of a material including polyethylene terephthalate (PET), polycarbonate (PC), polymethyl methacrylate (PMMA), or the like. .

The finishing cap 450 is located at both ends of the body 410 and can be used for sealing the power supply unit (not shown). In addition, the fin 450 is formed on the finishing cap 450, so that the lighting device 400 according to the embodiment can be used immediately without a separate device on the terminal from which the conventional fluorescent lamp is removed.

6 is an exploded perspective view of a liquid crystal display device including an optical sheet according to an embodiment.

6, the liquid crystal display device 500 may include a backlight unit 570 for providing light to the liquid crystal display panel 510 and the liquid crystal display panel 510 in an edge-light manner.

The liquid crystal display panel 510 can display an image using the light provided from the backlight unit 570. The liquid crystal display panel 510 may include a color filter substrate 512 and a thin film transistor substrate 514 facing each other with a liquid crystal therebetween.

The color filter substrate 512 can realize the color of an image to be displayed through the liquid crystal display panel 510.

The thin film transistor substrate 514 is electrically connected to a printed circuit board 518 on which a plurality of circuit components are mounted via a driving film 517. The thin film transistor substrate 514 may apply a driving voltage provided from the printed circuit board 518 to the liquid crystal in response to a driving signal provided from the printed circuit board 518.

The thin film transistor substrate 514 may include a thin film transistor and a pixel electrode formed as a thin film on another substrate of a transparent material such as glass or plastic.

The backlight unit 570 includes a light emitting device module 520 that outputs light, a light guide plate 530 that changes the light provided from the light emitting device module 520 into a surface light source and provides the light to the liquid crystal display panel 510, A plurality of films 550, 566, and 564 that uniformly distribute the luminance of light provided from the light guide plate 530 and improve vertical incidence, and a reflective sheet (not shown) that reflects light emitted to the rear of the light guide plate 530 to the light guide plate 530 540).

The light emitting device module 520 may include a PCB substrate 522 to mount a plurality of light emitting device packages 524 and a plurality of light emitting device packages 524 to form a module.

Particularly, the light emitting device module 520 includes a sealing portion (not shown) surrounding the light emitting device package 524 to prevent foreign matter from penetrating, thereby improving the reliability. In addition, . ≪ / RTI >

The backlight unit 570 includes a diffusion film 566 for diffusing light incident from the light guide plate 530 toward the liquid crystal display panel 510 and a prism film 550 for enhancing vertical incidence by condensing the diffused light And may include a protective film 564 for protecting the prism film 550. [

7 is an exploded perspective view of a liquid crystal display device including an optical sheet according to an embodiment. However, the parts shown and described in Fig. 6 are not repeatedly described in detail.

7, the liquid crystal display 600 may include a liquid crystal display panel 610 and a backlight unit 670 for providing light to the liquid crystal display panel 610 in a direct-down manner.

Since the liquid crystal display panel 610 is the same as that described in FIG. 4, detailed description is omitted.

The backlight unit 670 includes a plurality of light emitting element modules 623, a reflective sheet 624, a lower chassis 630 in which the light emitting element module 623 and the reflective sheet 624 are accommodated, And a plurality of optical films 660 disposed on the diffuser plate 640.

The light emitting device module 623 may include a PCB substrate 621 to mount a plurality of light emitting device packages 622 and a plurality of light emitting device packages 622 to form a module.

Particularly, the light emitting element module 623 includes a sealing portion (not shown) surrounding the light emitting element package 622 to prevent foreign matter from penetrating thereto, thereby improving reliability. Further, the reliability of the backlight unit 670 is improved, . ≪ / RTI >

The reflective sheet 624 reflects light generated from the light emitting device package 622 in a direction in which the liquid crystal display panel 610 is positioned, thereby improving light utilization efficiency.

The light emitted from the light emitting element module 623 is incident on the diffusion plate 640 and the optical film 660 is disposed on the diffusion plate 640. The optical film 660 is composed of a diffusion film 666, a prism film 650, and a protective film 664.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It should be understood that various modifications may be made by those skilled in the art without departing from the spirit and scope of the present invention.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It should be understood that various modifications may be made by those skilled in the art without departing from the spirit and scope of the present invention.

100: Light emitting element
110: substrate
120: bonding layer
130: capping layer
140: first electrode
150: channel layer
160: Light emitting structure
170: second electrode
180: protective layer
190: photo-conversion layer

Claims (12)

A light emitting structure including a first semiconductor layer, a second semiconductor layer, and an active layer between the first and second semiconductor layers;
A first electrode electrically connected to the first semiconductor layer;
A second electrode electrically connected to the second semiconductor layer; And
And a light conversion layer disposed on the first semiconductor layer in a predetermined pattern and converting a wavelength of light emitted from the active layer,
Wherein the light conversion layer comprises:
A first photo-conversion layer located at one side of the second electrode and including first photo-conversion particles having a first size; And
And a second light conversion layer disposed on one side of the first light conversion layer and including second light conversion particles having a second size. The method according to claim 1,
And the thickness of the second light conversion layer is 40 占 퐉 to 100 占 퐉. The method according to claim 1,
Wherein the first and second light conversion particles are formed by:
And a light emitting element that converts the light emitted from the active layer into light having the same wavelength. The method according to claim 1,
And the second size is 15 [mu] m to 30 [mu] m. The method according to claim 1,
The first size may be,
5 m to 7 m. The method according to claim 1,
A substrate below the first electrode,
Wherein the first electrode comprises:
A reflective electrode adjacent to the substrate; And
And a transparent electrode between the reflective electrode and the second semiconductor layer. The method according to claim 6,
And a capping layer between the substrate and the first electrode,
Wherein the capping layer comprises:
And a groove in which the first electrode is seated is formed. The method according to claim 1,
And a protective layer disposed on a side surface of the light emitting structure. 9. The method of claim 8,
And an insulating layer (channel layer) adjacent to a side surface of the first electrode and supporting the protective layer. The method according to claim 1,
Wherein the first size is smaller than the second size. The method according to claim 1,
And the thickness of the second light conversion layer is 40 占 퐉 to 100 占 퐉. An illumination system comprising the light-emitting device according to any one of claims 1 to 11.

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