KR20130027303A

KR20130027303A - Light emitting device

Info

Publication number: KR20130027303A
Application number: KR1020110090804A
Authority: KR
Inventors: 최병연; 정재웅; 이용경
Original assignee: 엘지이노텍 주식회사
Priority date: 2011-09-07
Filing date: 2011-09-07
Publication date: 2013-03-15

Abstract

PURPOSE: A light emitting device is provided to prevent a light extraction structure from being separated from a transparent electrode layer by forming an adhesion layer between the light extraction structures. CONSTITUTION: A light emitting structure(130) is located on a growth substrate(110). The light emitting structure includes a first conductive semiconductor layer(131), an active layer(132), and a second conductive semiconductor layer(133). A transparent electrode layer(140) is located on the light emitting structure. A plurality of light extraction structures are located on the transparent electrode layer. The light extraction structure includes zinc oxide. An adhesion layer(160) is located between the plurality of light extraction structures.

Description

[0001]

An embodiment relates to a light emitting element.

Light Emitting Diode (LED) is a device that converts an electric signal into a light form using the characteristics of a compound semiconductor, and is used for home appliances, remote controllers, electronic displays, indicators, and various automation devices. There is a trend.

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 usage area of the LED expands in this way, the luminance required for electric light used for living, electric light for rescue signals, etc. increases, and therefore, it is important to increase the light emission luminance of the LED.

In particular, for this purpose, various techniques for improving the light extraction efficiency of LEDs have been introduced. In the publication number 10-2011-0024038, a technical content of a method for manufacturing zinc oxide nanorods is disclosed. When used as a light extraction structure can increase the light extraction efficiency. However, the zinc oxide nanorods have a problem in that they are peeled from the transparent electrode layer because of poor adhesion to the transparent electrode layer.

The embodiment provides a light emitting device capable of preventing the light extraction structure from being peeled from the transparent electrode layer by forming an adhesive layer between the light extraction structures.

The light emitting device according to the embodiment includes a light emitting structure including a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer, a transparent electrode layer on the light emitting structure, and a plurality of light extracting structures on the transparent electrode layer. And an adhesive layer positioned between the plurality of light extracting structures.

The light emitting device according to the embodiment prevents the light extraction structure from being peeled from the transparent electrode layer, thereby improving light extraction efficiency by the light extraction structure, and improving the reliability of the light emitting device.

1 is a cross-sectional view illustrating a cross-sectional view of a horizontal light emitting device according to an embodiment, and FIG. 2 is an enlarged view of portion A of FIG. 1.
3 is a cross-sectional view showing a cross section of a vertical light emitting device according to the embodiment.
4 to 10 are views showing a manufacturing process of a light emitting device according to the embodiment.
11 is a cross-sectional view of a light emitting device package including a light emitting device according to an embodiment.
12A is a perspective view illustrating a lighting apparatus including a light emitting device module according to an embodiment, and FIG. 12B is a cross-sectional view taken along line C ′ of the lighting apparatus of FIG. 12A.
13 and 14 are exploded perspective views of a liquid crystal display including an optical sheet according to an embodiment.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as 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 scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.

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 flipping a device shown in the figure, a device described as "below" or "beneath" of another device may be placed "above" of another device. Thus, the exemplary term "below" can include both downward and upward directions. The device can also be oriented in other directions, so that spatially relative terms can be interpreted according to orientation.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the 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 otherwise defined, all terms (including technical and scientific terms) used in the present specification may be used in a sense that can be commonly understood by those skilled in the art. 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 cross-sectional view of a horizontal light emitting device according to an embodiment, and FIG. 2 is an enlarged view of portion A of FIG. 1.

1 and 2, the light emitting device 100 according to the embodiment includes a growth substrate 110, a buffer layer 120, a first conductivity type semiconductor layer 131, an active layer 132, and a second conductivity type semiconductor. It may include a light emitting structure 130 including a layer 133, a transparent electrode layer 140, a plurality of light extracting structure 150, an adhesive layer 160 and the first electrode 170 and the second electrode 180. have.

The growth substrate 110 may be formed of a conductive substrate or an insulating substrate. For example, sapphire (Al ₂ O ₃ ), SiC, Si, GaAs, GaN, ZnO, Si, GaP, InP, Ge, and Ga ₂ 0 It may be formed of at least one of _three . The growth substrate 110 may be wet-washed to remove impurities from the surface, and the growth substrate 110 may be patterned (Ptterned SubStrate, PSS) to improve light extraction efficiency, but is not limited thereto. .

The buffer layer 120 may be formed on the growth substrate 110 to mitigate lattice mismatch between the growth substrate 110 and the first conductive semiconductor layer 131 and to easily grow the conductive semiconductor layers.

The buffer layer 120 may be formed of AlInN / GaN stacked structure including AlN and GaN, InGaN / GaN stacked structure, and AlInGaN / InGaN / GaN stacked structure.

The light emitting structure 130 is positioned on the growth substrate 110 and may include a first conductive semiconductor layer 131, an active layer 132, and a second conductive semiconductor layer 133. The active layer 132 may be interposed between the semiconductor layer 131 and the second conductive semiconductor layer 133.

The first conductive semiconductor layer 131 is a semiconductor material having a composition formula of Al _x In _y Ga _(1-xy) N (0 = x = 1, 0 = y = 1, 0 = x + y = 1) For example, one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, and AlInN. And may be formed using another Group 5 element instead of N. For example, at least one of AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, and InP. In addition, when the first conductivity type semiconductor layer 131 is an N type conductivity type semiconductor layer, for example, Si, Ge, Sn, Se, Te, or the like may be included as an N type impurity.

The active layer 132 may be formed on the first conductive semiconductor layer 131. The active layer 132 is a region where electrons and holes are recombined. The active layer 132 transitions to a low energy level as the electrons and holes recombine, and may generate light having a corresponding wavelength.

The active layer 132 includes a semiconductor material having a composition formula of In _x Al _y Ga ₁ _-x- _y N (0? X? 1, 0? _Y? 1, 0? _X + y? 1) And may be formed of a single quantum well structure or a multi quantum well (MQW) structure.

Therefore, more electrons are collected at the lower energy level of the quantum well layer, and as a result, the probability of recombination of electrons and holes can be increased, thereby improving the light emitting effect. It may also include a quantum wire structure or a quantum dot structure.

The second conductivity type semiconductor layer 133 may be formed on the active layer 132. The second conductive semiconductor layer 133 may be implemented as a p-type conductive semiconductor layer to inject holes into the active layer 132. For example, the p-type conductive semiconductor layer is a semiconductor material having a composition formula of In _x Al _y Ga ₁ _-x- _y N (0≤x≤1, 0≤y≤1, 0≤x + y≤1), for example For example, it may be selected from GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, and the like, and may be doped with p-type impurities such as Mg, Zn, Ca, Sr, and Ba.

The first conductive semiconductor layer 131, the active layer 132, and the second conductive semiconductor layer 133 may be formed of metal organic chemical vapor deposition (MOCVD) or chemical vapor deposition (CVD). Deposition), Plasma-Enhanced Chemical Vapor Deposition (PECVD), Molecular Beam Epitaxy (MBE), Hydride Vapor Phase Epitaxy (HVPE), Sputtering It may be formed using, but is not limited thereto.

The transparent electrode layer 140 may be formed on the second conductive semiconductor layer 133.

The transparent electrode layer 140 may be formed of indium tin oxide (ITO), aluminum zinc oxide (AZO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), or indium zinc oxide (IZO). aluminum zinc oxide (IGZO), indium gallium zinc oxide (IGZO), indium gallium tin oxide (IGTO), antimony tin oxide (ATO), gallium zinc oxide (GZO), IrO _x , RuO _x , RuO _x / ITO, Ni / IrO _x / Au, or Ni / IrO _x / Au / ITO. However, it is not limited thereto.

A plurality of light extracting structures 150 may be formed on the transparent electrode layer 140. The light extraction structure 150 may be formed in a rod shape, the rod shape may be a cylindrical shape or a polygonal pillar shape, but is not limited thereto. In addition, the light extraction structure 150 may include zinc oxide (ZnO), for example, may be a zinc oxide (ZnO) nano-rod.

The light extraction structure 150 formed as described above may increase the light extraction efficiency. The light generated from the active layer 132 passes through the transparent electrode layer 140 and is emitted to the outside of the light emitting device 100. At this time, the refractive index of the transparent electrode layer 140 is greater than the refractive index of the outside air so that the transparent electrode layer 140 Total reflection may occur at the surface of

As described above, when the light extracting structure 150 having a refractive index similar to that of the transparent electrode layer 140 is formed on the surface of the transparent electrode layer 140 in the shape of a rod, the light incident on the light extracting structure 150 from the transparent electrode layer 140 is light. The light emitting device 100 may be transferred to the outside of the light emitting device 100 through total reflection within the extraction structure 150.

Therefore, light loss due to total reflection on the surface of the transparent electrode layer 140 may be reduced, and the light extraction phenomenon of the light extracting structure 150 may be used to increase the extraction efficiency of light generated in the active layer.

The plurality of light extracting structures 150 may be positioned at a distance from each other, and the adhesive layer 160 may be located in a space where the plurality of light extracting structures 150 are spaced apart from each other.

The adhesive layer 160 is in contact with the upper surface of the transparent electrode layer 140 and in contact with at least a portion of the side surface of the light extraction structure 150 to prevent the light extraction structure 150 from being separated from the transparent electrode layer 140.

The adhesive layer 160 may be formed of a material having a good adhesive strength with the transparent electrode layer 140, and may include SiO 2.

Referring to FIG. 2, in order for the light extracting structure 150 to transmit incident light using the optical waveguide phenomenon, the height h1 of the light extracting structure 150 must be greater than the wavelength of the incident light, and the light extracting structure ( If the height h1 of 150 is too large, the height h1 of the light extracting structure 150 may be 0.5 μm to 3 μm because the height h1 may be easily broken by an external impact.

In addition, the height h2 of the adhesive layer 160 may vary depending on the height h1 of the light extracting structure 150, but may be 0.5 μm or more in order to support and protect the light extracting structure 150. When the height h2 of the 160 is formed to be greater than the height h1 of the light extraction structure 150 to cover the light extraction structure 150, the height h2 may affect the light extraction efficiency. The height h2 may be smaller than or equal to the height h1 of the light extracting structure 150 and may be 3 μm or less.

Referring back to FIG. 1, the first electrode 170 may be formed on the first conductive semiconductor layer 131, and the second electrode 180 may be formed on the second conductive semiconductor layer 133 and the transparent electrode layer 140. ) May be formed.

In this case, mesa etching may be performed from the second conductive semiconductor layer 133 to a part of the first conductive semiconductor layer 131 to secure a space for forming the first electrode 160. The first electrode 160 may be formed in an etched and exposed area of the surface of the first conductive semiconductor layer 131.

In addition, the first electrode 170 and the second electrode 160 may be formed of a conductive material, for example, indium (In), cobalt (Co), silicon (Si), germanium (Ge), and gold (Au). ), Palladium (Pd), platinum (Pt), ruthenium (Ru), rhenium (Re), magnesium (Mg), zinc (Zn), hafnium (Hf), tantalum (Ta), rhodium (Rh), iridium (Ir) ), Tungsten (W), titanium (Ti), silver (Ag), chromium (Cr), molybdenum (Mo), niobium (Nb), aluminum (Al), nickel (Ni) and copper (Cu) It may be formed or formed of two or more alloys, it may be formed by stacking two or more different materials.

3 is a cross-sectional view showing a cross section of a vertical light emitting device according to the embodiment.

Referring to FIG. 3, the vertical light emitting device 200 according to the embodiment includes a support substrate 210, a first conductive semiconductor layer 231, an active layer 232, and a second conductive semiconductor layer 233. The light emitting structure 230, the second electrode layer 240, the conductive layer 280, the transparent electrode layer 290, the plurality of light extracting structures 250, the adhesive layer 260, and the first electrode 270 may be included. have. Compared to the embodiment of FIG. 1, the substrate further includes a support substrate 210, a conductive layer 280, and a second electrode layer 240, and the transparent electrode layer 290 is formed to be in contact with the first conductive semiconductor layer 233. There is a difference. Description of the same components will be omitted below.

Support substrate 210 may be formed of a conductive material, for example, gold (Au), nickel (Ni), tungsten (W), molybdenum (Mo), copper (Cu), aluminum (Al), tantalum ( Ta), silver (Ag), platinum (Pt), chromium (Cr), Si, Ge, GaAs, ZnO, GaN, Ga ₂ O ₃ or SiC, SiGe, CuW, or any one of two or more alloys It may be formed by stacking two or more different materials.

The support substrate 210 may facilitate the emission of heat generated from the light emitting device 200 to improve the thermal stability of the light emitting device 200.

A coupling layer (not shown) may be formed on the support substrate 210 to couple the support substrate 210 and the conductive layer 280. The bonding layer (not shown) is, for example, a group consisting of gold (Au), tin (Sn), indium (In), silver (Ag), nickel (Ni), niobium (Nb), and copper (Cu). It may be formed of a material selected from or alloys thereof.

The conductive layer 280 is a material selected from the group consisting of nickel (nickel), platinum (Pt), titanium (Ti), tungsten (W), vanadium (V), iron (Fe), and molybdenum (Mo). Or they may be made of an alloy optionally included.

The conductive layer 280 may be formed using a sputter deposition method. When using a sputtering deposition method, when ionized atoms are accelerated by an electric field and impinge on the source material of the conductive layer 280, atoms of the source material are ejected and deposited. In addition, according to the embodiment, an electrochemical metal deposition method, a bonding method using a eutectic metal, or the like may be used. In some embodiments, the conductive layer 280 may be formed of a plurality of layers.

The conductive layer 280 has an effect of minimizing mechanical damage (breaking or peeling, etc.) that may occur in the manufacturing process of the light emitting device.

In addition, the conductive layer 280 has an effect of preventing the metal material constituting the support substrate 210 or the bonding layer (not shown) from being diffused into the light emitting structure 230.

Referring to FIG. 3 again, the second electrode layer 240 may selectively use a metal and a transparent conductive layer, and provide power to the light emitting structure 230. The second electrode layer 240 may be formed including a conductive material. For example, nickel (Ni), platinum (Pt), ruthenium (Ru), iridium (Ir), rhodium (Rh), tantalum (Ta), molybdenum (Mo), titanium (Ti), silver (Ag), tungsten (W), copper (Cu), chromium (Cr), palladium (Pd), vanadium (V), cobalt (Co), niobium (Nb), zirconium (Zr), indium tin oxide (ITO), Aluminum zinc oxide (AZO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), indium gallium (IGTO) tin oxide), antimony tin oxide (ATO), gallium zinc oxide (GZO), IrO _x , RuO _x , RuO _x / ITO, Ni / IrO _x / Au, or Ni / IrO _x / Au / ITO Can be. However, it is not limited thereto.

In addition, the second electrode layer 240 may be formed as a single layer or a multilayer of a reflective electrode material having ohmic characteristics.

The second electrode layer 240 is a structure of an ohmic layer 241 / reflection layer 242 / bonding layer (not shown), a laminated structure of the ohmic layer 241 / reflection layer 242, or a reflective layer (including ohmic) 242. ) / Bonding layer (not shown), but is not limited thereto.

The ohmic layer 241 is in ohmic contact with a lower surface of the light emitting structure (eg, the second conductivity-type semiconductor layer 233), and may be formed in a layer or a plurality of patterns. The ohmic layer 241 may selectively use a light transmitting conductive layer and a metal. For example, indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), and indium aluminum zinc (AZO) oxide), IGZO (indium gallium zinc oxide), IGTO (indium gallium tin oxide), AZO (aluminum zinc oxide), ATO (antimony tin oxide), GZO (gallium zinc oxide), IZON (IZO Nitride), AGZO (Al- Ga ZnO), IGZO (In-Ga ZnO), ZnO, IrOx, RuOx, NiO, RuOx / ITO, Ni / IrOx / Au, and Ni / IrOx / Au / ITO, Ag, Ni, Cr, Ti, Al, Rh , Pd, Ir, Sn, In, Ru, Mg, Zn, Pt, Au, can be formed including at least one of Hf, and is not limited to these materials. The ohmic layer 241 may be formed by sputtering or electron beam deposition. The reflective layer 242 reflects light toward the upper direction of the light emitting device 200 when some of the light generated from the active layer 232 of the light emitting structure 230 is directed toward the support substrate 210. It is possible to improve the light extraction efficiency of 200).

The reflective layer 242 is made of a metal layer including aluminum (Al), silver (Ag), nickel (Ni), platinum (Pt), rhodium (Rh), or an alloy containing Al, Ag, Pt or Rh, It may be formed in multiple layers using the metal material and light transmitting conductive materials such as IZO, IZTO, IAZO, IGZO, IGTO, AZO, and ATO. In addition, the reflective layer 242 may be laminated with IZO / Ni, AZO / Ag, IZO / Ag / Ni, AZO / Ag / Ni, or the like. In addition, when the reflective layer 242 is formed of a material in ohmic contact with the light emitting structure (eg, the second conductivity-type semiconductor layer 233), the ohmic layer 241 may not be separately formed, but is not limited thereto.

Although the reflective layer 242 and the ohmic layer 241 are described as having the same width and length, at least one of the width and the length may be different and the present invention is not limited thereto.

The bonding layer (not shown) may include a barrier metal or a bonding metal such as titanium (Ti), gold (Au), tin (Sn), nickel (Ni), chromium (Cr) ), Indium (In), bismuth (Bi), copper (Cu), silver (Ag), or tantalum (Ta).

4 to 10 are views showing a manufacturing process of a light emitting device according to the embodiment.

Referring to FIG. 4, first, the buffer layer 120, the first conductive semiconductor layer 131, the active layer 132, and the second conductive semiconductor layer 133 are sequentially formed on the growth substrate 110.

The growth substrate 110 may be selected from the group consisting of sapphire substrate (Al ₂ O ₃ ), GaN, SiC, ZnO, Si, GaP, InP, and GaAs.

The buffer layer 120 may be formed of a combination of Group 3 and Group 5 elements, or may be formed of any one of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, and AlInN, and dopants may be doped.

An undoped semiconductor layer may be formed on the growth substrate 110 or the buffer layer 120, and either or both of the buffer layer 120 and the undoped conductive semiconductor layer (not shown) are formed. It may or may not be formed and is not limited to this structure.

The first conductive semiconductor layer 131, the active layer 132, and the second conductive semiconductor layer 133 may be sequentially formed on the growth substrate 110.

The first conductive semiconductor layer 131 injects silane gas (SiH4) containing N-type impurities such as trimethyl gallium gas (TMGa), ammonia gas (NH3), nitrogen gas (N2), and silicon (Si) into the chamber. Can be formed.

The active layer 132 may be grown in a nitrogen atmosphere while injecting trimethyl gallium gas (TMGa) and trimethyl indium gas (TMIn), and a single quantum well structure, a multi quantum well structure (MQW), and a quantum line It may be formed of at least one of a wire structure or a quantum dot structure.

The second conductive semiconductor layer 133 has trimethyl gallium gas (TMGa), trimethyl aluminum gas (TMAl), bicetyl cyclopentadienyl magnesium (EtCp2Mg) {Mg ( C2H5C5H4) 2} and the like can be grown, but is not limited thereto.

Then, the manufacturing process of the horizontal light emitting device and the vertical light emitting device is different.

5 to 7 are views showing the manufacturing process of the horizontal light emitting device after the process shown in FIG.

5 to 7, the transparent electrode layer 140 may be formed on the second conductive semiconductor layer 133, and the first conductive semiconductor layer 131 may be formed on the second conductive semiconductor layer 133. Mesa is etched up to a part of the surface by the Reactive Ion Etching (RIE) method. For example, when an insulating substrate such as a sapphire substrate is used, electrodes can not be formed under the substrate. Therefore, mesa etching is performed from the second conductivity type semiconductor layer 133 to a portion of the first conductivity type semiconductor layer 131 , It is possible to secure a space in which electrodes can be formed. Accordingly, the first electrode 170 may be formed in an etched and exposed area of the surface of the first conductive semiconductor layer 131.

A plurality of light extracting structures 150 may be formed on the transparent electrode layer 140.

The light extracting structure 150 may be formed of a zinc oxide (ZnO) nanorod using a hydrothermal synthesis method.

In the growth method of zinc oxide (ZnO) nanorods, a seed solution is first prepared by heating a mixture of zinc acetate and ethanol at 90 ° C., and then depositing the seed solution on the transparent electrode layer 140. Afterwards, zinc ions (Zn ²⁺ ) contained in the seed solution may be heat-treated at 100 ° C. for 15 to 20 minutes to crystallize into zinc nanoparticles to form a seed layer capable of growing zinc oxide nanorods. . Next, when the seed layer is immersed in a mixed solution of zinc nitrate hexahydrate and hexamethylenetetramin, zinc oxide (ZnO) nanorods may be grown on the seed layer.

An adhesive layer 160 may be formed between the plurality of light extracting structures 150 formed of zinc oxide (ZnO) nanorods.

The adhesive layer 160 may be formed by depositing SiO 2 on the transparent electrode layer 140 using a PECVD method.

A portion of the light extracting structure 150 and the adhesive layer 160 are etched to expose the transparent electrode layer 140 and the second conductive semiconductor layer 133 so that the second conductive semiconductor layer 133 and the transparent electrode layer 140 are exposed. The second electrode 180 may be formed on the second electrode 180.

8 to 10 are diagrams illustrating a manufacturing process of the vertical light emitting device after the process shown in FIG. 4.

Referring to FIG. 8, a second electrode layer 240 may be formed on the second conductive semiconductor layer 133, and a support substrate 210 on which the conductive layer 280 is disposed may be bonded and bonded. In this case, the growth substrate 110 disposed on the first conductivity type semiconductor layer 131 may be separated.

At this time, the growth substrate 110 can be removed by a physical or / and chemical method, and the physical method can be removed, for example, by a LLO (laser lift off) method.

Meanwhile, after the growth substrate 110 is removed, the buffer layer 120 disposed on the light emitting structure 130 may be removed. In this case, the buffer layer 120 may be removed through a dry or wet etching method or a polishing process.

9 and 10, a transparent electrode layer 290 may be formed on the first conductive semiconductor layer 131, and the light extracting structure 250 and the adhesive layer may be formed on the transparent electrode layer 290 as described above. 260 may be formed.

In addition, although not shown, the outer area of the light emitting structure 230 may be etched to have an inclination, and a passivation (not shown) may be formed on a part or the entire area of the outer circumferential surface of the light emitting structure 230. Passivation (not shown) may be formed of an insulating material.

The first electrode 270 may be formed on the surface of the first conductive semiconductor layer 231.

In addition, at least one process in the process sequence shown in FIGS. 4 to 10 may be reversed, but the present invention is not limited thereto.

11 is a cross-sectional view showing a cross section of a light emitting device package including a light emitting device according to the embodiment.

Referring to FIG. 11, the light emitting device package 300 according to the embodiment includes a body 310 in which a cavity is formed, a light source unit 320 mounted in a cavity of the body 310, and an encapsulant 350 filled in a cavity. can do.

The body 310 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 (Al2O3), beryllium oxide (BeO), a printed circuit board (PCB, Printed Circuit Board), it may be formed of at least one. 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 and described with reference to FIGS. 1 to 3. The light emitting device may be, for example, a colored light emitting device emitting light of red, green, blue, white, or the like, or an ultraviolet (UV) light emitting device emitting ultraviolet light, but is not limited thereto. 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, and may reflect light generated from the light source unit 320 to increase light efficiency, and also generate heat generated from the light source unit 320. Can be discharged to the outside.

11 illustrates that both the first electrode 330 and the second electrode 340 are bonded to the light source unit 320 by the wire 360, but 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 unit 320 by the wire 360, or may be electrically connected to the light source unit 320 without the wire 360 by a flip chip method. have.

The first electrode 330 and the second electrode 340 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), hafnium (Hf), ruthenium (Ru), iron (Fe) may include one or more materials or alloys. In addition, the first electrode 330 and the second electrode 340 may be formed to have a single layer or a multilayer structure, but 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 transparent silicone, epoxy, and other resin materials, and may be formed by filling in a cavity and then ultraviolet 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 implement white light.

The phosphor (not shown) included in the encapsulant 350 may be a blue light emitting phosphor, a cyan light emitting phosphor, a green light emitting phosphor, a yellow green light emitting phosphor, a yellow light emitting phosphor, or a yellow red light emitting phosphor according to a wavelength of light emitted from the light source unit 320. One of orange luminescent phosphor, and red luminescent phosphor can be applied.

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

12A is a perspective view illustrating a lighting apparatus including a light emitting device module according to an embodiment, and FIG. 12B is a cross-sectional view illustrating a C-C 'cross section of the lighting apparatus of FIG. 12A.

That is, FIG. 12B is a cross-sectional view of the lighting apparatus 400 of FIG. 12A cut in the plane of the longitudinal direction Z and the height direction X, and viewed in the horizontal direction Y. FIG.

12A and 12B, the lighting device 400 may include a body 410, a cover 430 fastened to the body 410, and a closing cap 450 positioned at both ends of the body 410. have.

The lower surface of the body 410 is fastened to the light emitting device module 440, the body 410 is conductive and so that the heat generated from the light emitting device package 444 can be discharged to the outside through the upper surface of the body 410 The heat dissipation effect may be formed of an excellent metal material, but is not limited thereto.

In particular, the light emitting device module 440 may include a sealing part (not shown) surrounding the light emitting device package 444 to prevent penetration of foreign matters, thereby improving reliability, and also providing reliable lighting apparatus 400. Implementation of.

The light emitting device package 444 may be mounted on the substrate 442 in multiple colors and in multiple rows to form a module. The light emitting device package 444 may be mounted at the same interval or may be mounted at various separation distances as necessary to adjust brightness. As the substrate 442, a metal core PCB (MCPCB) or a PCB made of FR4 may be used.

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

The cover 430 protects the light emitting device module 440 from the outside and the like. In addition, the cover 430 may include diffusing particles to prevent glare of the light generated from the light emitting device package 444 and to uniformly emit light to the outside, and may also 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 either side. In addition, a phosphor may be applied to at least one of an inner surface and an outer surface of the cover 430.

On the other hand, since the light generated from the light emitting device package 444 is emitted to the outside through the cover 430, the cover 430 should be excellent in the light transmittance, sufficient to withstand the heat generated in the light emitting device package 444 The cover 430 is formed of a material including polyethylene terephthalate (PET), polycarbonate (PC), or polymethyl methacrylate (PMMA). It is preferable.

Closing cap 450 is located at both ends of the body 410 may be used for sealing the power supply (not shown). In addition, the closing cap 450 is a power pin 452 is formed, the lighting device 400 according to the embodiment can be used immediately without a separate device to the terminal from which the existing fluorescent lamps are removed.

13 and 14 are exploded perspective views of a liquid crystal display device including an optical sheet according to an embodiment.

FIG. 13 illustrates an edge-light method, and the liquid crystal display 500 may include a liquid crystal display panel 510 and a backlight unit 570 for providing light to the liquid crystal display panel 510.

The liquid crystal display panel 510 may display an image by using 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 interposed therebetween.

The color filter substrate 512 may implement colors of an image displayed through the liquid crystal display panel 510.

The thin film transistor substrate 514 is electrically connected to the printed circuit board 518 on which a plurality of circuit components are mounted through the 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 of a thin film on another substrate of a transparent material such as glass or plastic.

The backlight unit 570 may convert the light provided from the light emitting device module 520, the light emitting device module 520 into a surface light source, and provide the light guide plate 530 to the liquid crystal display panel 510. Reflective sheet for reflecting the light emitted from the rear of the light guide plate 530 and the plurality of films 550, 566, 564 to uniform the luminance distribution of the light provided from the 530 and improve the vertical incidence ( 540.

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

In particular, the light emitting device module 520 may include a sealing part (not shown) surrounding the light emitting device package 524 to prevent foreign matter from penetrating, thereby improving reliability, and also providing reliable backlight unit 570. Implementation of.

Meanwhile, 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 condensing the diffused light to improve vertical incidence. ), And may include a protective film 564 to protect the prism film 550.

14 is an exploded perspective view of a liquid crystal display device including the optical sheet according to the embodiment. However, the parts shown and described in FIG. 13 will not be repeatedly described in detail.

14 is a direct view, 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.

Since the liquid crystal display panel 610 is the same as that described with reference to FIG. 10, a detailed description thereof will be omitted.

The backlight unit 670 may include a plurality of light emitting device modules 623, a reflective sheet 624, a lower chassis 630 in which the light emitting device modules 623 and the reflective sheet 624 are accommodated, and an upper portion of the light emitting device module 623. It may include a diffusion plate 640 and a plurality of optical film 660 disposed in the.

LED Module 623 A plurality of light emitting device packages 622 and a plurality of light emitting device packages 622 may be mounted to include a PCB substrate 621 to form a module.

In particular, the light emitting device module 623 may include a sealing part (not shown) surrounding the light emitting device package 622 to prevent foreign matter from penetrating, thereby improving reliability, and also providing reliable backlight unit 670. Implementation of.

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

On the other hand, the light generated from the light emitting device module 623 is incident on the diffusion plate 640, the optical film 660 is disposed on the diffusion plate 640. The optical film 660 includes a diffusion film 666, a prism film 650, and a protective film 664.

Although the above has been illustrated and described with respect to preferred embodiments of the present invention, the present invention is not limited to the specific embodiments described above, but in the art to which the invention pertains without departing from the spirit 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.

100, 200: light emitting device 110: growth substrate
120: buffer layer 130: light emitting structure
140: transparent electrode layer 150: light extraction structure
160: Adhesive layer

Claims

A light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer;
A transparent electrode layer on the light emitting structure;
A plurality of light extracting structures positioned on the transparent electrode layer; And
Light emitting device comprising an adhesive layer located between the plurality of light extraction structure.

The method of claim 1,
The plurality of light extracting structures are rod-shaped light emitting device.

The method of claim 1,
The plurality of light extracting structures include zinc oxide (ZnO).

The method of claim 1,
The adhesive layer is a light emitting device containing SiO2.

The method of claim 1,
The adhesive layer is in contact with the upper surface of the transparent electrode layer.

The method of claim 1,
The light emitting device has a height of 0.5um to 3um of the plurality of light extracting structures.

The method of claim 1,
The adhesive layer has a height of 0.5um to 3um.

The method of claim 1,
The height of the adhesive layer is less than or equal to the height of the light extraction structure.

The method of claim 1,
Further includes a growth substrate,
The first conductive semiconductor layer, the active layer and the second conductive semiconductor layer are sequentially disposed on the growth substrate, wherein the transparent electrode layer is in contact with the second conductive semiconductor layer.

10. The method of claim 9,
The light emitting device further comprises a first electrode on the first conductive semiconductor layer and a second electrode on the transparent electrode layer.

The method of claim 1,
Further comprising a support substrate,
The second conductive semiconductor layer, the active layer and the first conductive semiconductor layer are sequentially positioned on the support substrate, wherein the transparent electrode layer is in contact with the first conductive semiconductor layer.

The method of claim 11,
And a second electrode layer disposed between the support substrate and the second conductive semiconductor layer, and a first electrode disposed on the transparent electrode layer.