KR102065383B1 - Light emitting device - Google Patents

Abstract

The embodiment relates to a light emitting device. The light emitting device according to the embodiment includes a first conductive semiconductor layer, an active layer disposed on the first conductive semiconductor layer, and an active layer disposed on the second conductive semiconductor layer and the second conductive semiconductor layer. The substrate may be spaced apart from each other by a predetermined distance, and may include a plurality of ohmic patterns including a first material and a second material layer disposed between the plurality of ohmic patterns.

Description

Light emitting device

The embodiment relates to a light emitting device.

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 mount device type for direct mounting on a printed circuit board (PCB) board. Accordingly, LED lamps, which are used as display elements, are also being developed as surface mount device types. . Such a surface mounting element can replace a conventional simple lighting lamp, which is used as a lighting display for various colors, a character display and an image display.

As the usage area of the LED is widened as described above, the luminance required for a lamp used for living, a lamp for rescue signals, etc. increases, and thus, it is necessary to increase the luminous efficiency in order to increase the luminous luminance of the LED.

In order for the light emitting device to emit light in the ultraviolet region, the light emitting structure should include Al, and in the case of the nitride semiconductor layer containing Al, it is very difficult to form ohmic because the band gap energy is very large. Accordingly, GaN or InGaN is used as the ohmic contact layer. In the case of GaN or InGaN, the bandgap energy is small, so that light in the ultraviolet region is absorbed.

Meanwhile, in Korean Patent Laid-Open Publication No. 10-2009-0012494, a transparent electrode layer forming a photonic crystal structure by having a plurality of holes arranged in a size and a period capable of forming a photon band gap with respect to light emitted from an active layer and the first Provided is a photonic crystal light emitting device including first and second electrodes electrically connected to a conductive semiconductor layer and a transparent electrode layer, respectively.

An object of the present invention is to provide a light emitting device including an ohmic contact layer capable of minimizing absorption loss of light generated in an active layer.

The light emitting device according to the embodiment includes a first conductive semiconductor layer, an active layer disposed on the first conductive semiconductor layer, and an active layer disposed on the second conductive semiconductor layer and the second conductive semiconductor layer. The substrate may be spaced apart from each other by a predetermined distance, and may include a plurality of ohmic patterns including a first material and a second material layer disposed between the plurality of ohmic patterns.

The light emitting device according to the embodiment may include a plurality of ohmic patterns spaced apart from each other and a reflective layer or a transmission layer between the ohmic patterns, thereby minimizing absorption loss of light generated in the active layer, thereby increasing the luminous efficiency of the light emitting device. have.

1 is a cross-sectional view showing a cross section of a horizontal light emitting device according to the embodiment.
FIG. 2 is an enlarged view of a 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 is an enlarged view of a portion B of FIG. 3.
5 to 10 are views showing a manufacturing process of the 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 the embodiment.
12A is a perspective view illustrating a lighting device including a light emitting device module according to an embodiment, and FIG. 12B is a cross-sectional view taken along line CC ′ of the lighting device 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. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various different forms, and only the embodiments make the disclosure of the present invention complete, and the general knowledge in the art to which the present invention belongs. It is provided to fully inform the person having the scope of the invention, which is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

The spatially relative terms " below ", " beneath ", " lower ", " above ", " upper " It may be used to easily describe the correlation of a device or components with other devices or components. Spatially relative terms are to be understood as terms that include different directions of the device in use or operation in addition to the directions shown in the figures. 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 encompass both an orientation of above and below. 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 this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, “comprises” and / or “comprising” refers to the presence of one or more other components, steps, operations and / or elements. Or does not exclude 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. In addition, the terms defined in the commonly used dictionaries are not ideally or excessively interpreted unless they are specifically defined clearly.

In the drawings, the thickness or size of each layer is exaggerated, omitted, or schematically illustrated for convenience and clarity of description. In addition, the size and area of each component does not necessarily reflect the actual size or area.

In addition, the angle and direction mentioned in the process of describing the structure of the light emitting device in the embodiment are based on those described in the drawings. In the description of the structure constituting the light emitting device in the specification, if the reference point and the positional relationship with respect to the angle is not clearly mentioned, reference is made to related drawings.

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

Referring to FIG. 1, the light emitting device 100 according to the embodiment may include 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 layer 133. ), A plurality of ohmic patterns 140, a second material layer 145, a first electrode 150, and a second electrode 160.

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 conductivity type semiconductor layer 131, an active layer 132, and a second conductivity type 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 compositional formula of Al _x In _y Ga _(1-xy) N (0 = x = 1, 0 = y = 1, 0 = x + y = 1), for example For example, at least one of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, and AlInN may be formed. It may also be formed using other Group 5 elements instead of N. For example, it may be formed of any one or more of AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, and InP. In addition, when the first conductivity-type semiconductor layer 131 is an n-type semiconductor layer, for example, the n-type impurity may include Si, Ge, Sn, Se, Te, or the like. Hereinafter, the first conductive semiconductor layer will be described as an example of an n-type semiconductor layer.

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 is, for example, including a semiconductor material having a compositional formula of _{In x Al y Ga 1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x + y≤1) It may be formed, and may be formed of a single quantum well structure or a multi quantum well structure (MQW).

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. In addition, a quantum wire structure or a quantum dot structure may be included.

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 semiconductor layer to inject holes into the active layer 132. For example, the p-type 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 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.

On the second conductive semiconductor layer 133, a plurality of ohmic patterns 140 including the first material may be spaced apart from each other by a predetermined distance.

The first material may include any one of GaN and InGaN, and may have a smaller bandgap energy than the material constituting the second conductive semiconductor layer 133. Accordingly, the ohmic can be easily formed.

A second material layer 145 including a first material and another second material may be formed between the plurality of ohmic patterns 140, and the second material layer 145 may include at least one of a transmission layer and a reflection layer. Can be.

Referring to FIG. 2, the second material layer 145 is formed as a transparent layer. When the second material layer 145 is formed as a transmissive layer, the transmissive layer may be formed of 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 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. In addition, the transmission layer 145 may be formed of a material having a transmittance of 80% or more of the light generated from the active layer 132.

Meanwhile, a part of the light generated by the active layer 132 may be incident to the ohmic pattern 140 or may be incident to the transmission layer 145. In this case, light incident on the ohmic pattern 140 may be absorbed or transmitted through the ohmic pattern 140, and light incident on the transmission layer 145 may be extracted to the outside of the light emitting device.

As described above, light incident on the transmission layer 145 may be extracted to the outside of the light emitting device, and thus the light extraction efficiency of the light emitting device may be increased.

Referring to FIG. 2, the heights of the plurality of ohmic patterns 140 and the second material layer 145 may be the same. In addition, the overall width of the plurality of ohmic patterns 140 may be 1 to 9 times the total width of the second material layer 145.

For example, the width of each of the plurality of ohmic patterns 140 may be referred to as t1, t2, t3,..., And the width of each of the second material layers 145 may be referred to as o1, o2, o3,. When t1 + t2 + t3 + ... may be from 1 to 9 times o1 + o2 + o3 + ...

 When the overall width of the plurality of ohmic patterns 140 is smaller than the overall width of the second material layer 145, the area in contact with the ohmic decreases, so that a stable ohmic may not be formed, and the plurality of ohmic patterns 140 may be formed. If the overall width of the N-A is greater than nine times the overall width of the second material layer 145, absorption of light generated in the active layer may increase.

Referring back to FIG. 1, the first electrode 150 may be formed on the first conductive semiconductor layer 131, and the second electrode 160 may be formed on the plurality of ohmic patterns 140 and the second material layer 145. ) May be formed.

In this case, mesa etching may be performed from the second conductive semiconductor layer 133 to a portion of the first conductive semiconductor layer 131 to secure a space for forming the first electrode 150. The first electrode 150 may be formed in an etched and exposed area of the surface of the first conductive semiconductor layer 131.

In addition, the first electrode 150 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 may include 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 may include a plurality of ohmic patterns 240, a second material layer 245, a second electrode layer 260, a conductive layer 270, and a first electrode 250. Compared with the embodiment of FIG. 1, there is a difference that the support substrate 210, the conductive layer 270, and the second electrode layer 260 are further included. 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 bonding layer (not shown) may be formed on the support substrate 210 to couple the support substrate 210 and the conductive layer 270 to each other. 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 270 is a material selected from the group consisting of nickel (Ni-nickel), platinum (Pt), titanium (Ti), tungsten (W), vanadium (V), iron (Fe), and molybdenum (Mo). Or they may be made of an alloy optionally included.

Conductive layer 270 may be formed using a sputtering deposition method. When using the sputter deposition method, when ionized atoms are accelerated by an electric field and collide with the source material of the conductive layer 270, 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 270 may be formed of a plurality of layers.

The conductive layer 270 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 270 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 260 may selectively use a metal and a transparent conductive layer, and provide power to the light emitting structure 230. The second electrode layer 260 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 260 may be formed as a single layer or multiple layers of a reflective electrode material having ohmic characteristics.

The second electrode layer 260 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.

The ohmic layer 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), indium aluminum zinc oxide (IZAO), and 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, Hf may be formed, including, but not limited to such materials. The ohmic layer may be formed by sputtering or electron beam deposition. The reflective layer reflects the 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.

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

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

The bonding layer may be a barrier metal, or a bonding metal such as titanium (Ti), gold (Au), tin (Sn), nickel (Ni), chromium (Cr), gallium (Ga), indium ( In), bismuth (Bi), copper (Cu), silver (Ag) or tantalum (Ta).

Meanwhile, referring to FIG. 4, the second material layer 245 is formed as a reflective layer. The reflective layer 245 may include at least one of SiO 2, TiO 2, and Ta 2 O 5.

The reflective layer 245 may be formed of a DBR layer in which a first layer 245a having a first refractive index and a second layer 245b having a second refractive index are alternately stacked.

In addition, the reflective layer 245 may be formed of a material having a reflectivity of 90% or more of light generated from the active layer 232.

Meanwhile, a part of the light generated by the active layer 232 may be incident to the ohmic pattern 240 or may be incident to the reflective layer 245. In this case, the light incident on the ohmic pattern 240 may be absorbed or transmitted through the ohmic pattern 240, and the light incident on the reflective layer 245 proceeds upward toward the light emitting device 200. It is possible to improve the light extraction efficiency of 200).

Meanwhile, the second material layer 245 may be formed as a transmissive layer as described in FIG. 2 as well as the reflective layer, but is not limited thereto.

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

Referring to FIG. 5, 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 is a silane gas (SiH ₄₎ containing N-type impurities such as trimethyl gallium gas (TMGa), ammonia gas (NH ₃ ), nitrogen gas (N ₂ ), and silicon (Si) in the chamber. ) Can be formed by injection.

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 conductivity-type semiconductor layer 133 is formed in a chamber of 960? Trimethyl gallium gas (TMGa), trimethyl aluminum gas (TMAl), bicetyl cyclopentadienyl magnesium (EtCp ₂ Mg) {Mg (C ₂ H ₅ C ₅ H ₄ ) ₂ } It can be grown by injecting, but is not limited thereto.

Referring to FIG. 6, a plurality of ohmic patterns 140 may be formed by growing a GaN or InGaN layer, and then etching or by selectively growing a GaN or InGaN layer using a mask. In this case, the number, shape, and arrangement of the plurality of ohmic patterns may be variously modified.

Referring to FIG. 7, a reflective layer or a transmission layer 145 may be formed between the plurality of ohmic patterns 140.

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

8 is a view showing a manufacturing process of the horizontal light emitting device after the process shown in FIG.

Referring to FIG. 8, Mesa is etched from the second conductive semiconductor layer 133 to a portion of the first conductive semiconductor layer 131 by a reactive ion etching (RIE) method. For example, when an insulating substrate is used, such as a sapphire substrate, an electrode cannot be formed under the substrate, thereby mesa etching from the second conductive semiconductor layer 133 to a part of the first conductive semiconductor layer 131. The space for forming the electrode can be secured. Accordingly, the first electrode 150 may be formed in an etched and exposed area of the surface of the first conductive semiconductor layer 131. In addition, the second electrode 150 may be formed on the plurality of ohmic patterns 140 and the second material layer 145.

9 and 10 are views showing a manufacturing process of the vertical light emitting device after the process shown in FIG.

Referring to FIG. 9, the second electrode layer 260 may be formed on the plurality of ohmic patterns 140 and the second material layer 145, and the support substrate 210 on which the conductive layer 270 is disposed is bonded and bonded. Can be. In this case, the growth substrate 110 disposed on the first conductivity type semiconductor layer 131 may be separated.

In this case, the growth substrate 210 may be removed by a physical or / and chemical method, and the physical method may be removed by, for example, a laser lift off (LLO) method.

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

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 250 may be formed on the surface of the first conductive semiconductor layer 231.

At least one process in the process sequence illustrated in FIGS. 5 to 10 may be reversed, but 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 4. 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 devices may be mounted.

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

In addition, the first lead frame 330 and the second lead frame 340 are electrically separated from each other, it is possible to reflect the light generated from the light source unit 320 to increase the light efficiency, and also generated in the light source unit 320 The waste heat to the outside.

11 illustrates that both the first lead frame 330 and the second lead frame 340 are bonded to the light source unit 320 by the wire 360, but is not limited thereto. In particular, in the case of a vertical light emitting device One of the first lead frame 330 and the second lead frame 340 may be bonded to the light source unit 320 by the wire 360, and the light source unit 320 without the wire 360 by a flip chip method. It may be electrically connected.

The first lead frame 330 and the second lead frame 340 is a metal material, for example, titanium (Ti), copper (Cu), nickel (Ni), gold (Au), chromium (Cr), tantalum Aluminum (Ta), Platinum (Pt), Tin (Sn), Silver (Ag), Phosphorus (P), Aluminum (Al), Indium (In), Palladium (Pd), Cobalt (Co), Silicon (Si), It may include one or more materials or alloys of germanium (Ge), hafnium (Hf), ruthenium (Ru), iron (Fe). In addition, the first lead frame 330 and the second lead frame 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 blue green 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 further 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 should be provided with heat resistance, and the cover 430 is made of a material including polyethylene terephthalate (PET), polycarbonate (PC), polymethyl methacrylate (PMMA), or the like. It is preferable to form.

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 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. 13, 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 above-described specific embodiments, and the present invention is not limited to the scope of the present 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.

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 above-described specific embodiments, and the present invention is not limited to the scope of the present 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.

110: growth substrate 120: buffer layer
131: first conductive semiconductor layer 132: active layer
133: second conductive semiconductor layer 140: ohmic pattern
150: first electrode 160: second electrode

Claims (12)

A buffer layer disposed on the substrate;
A first conductivity type semiconductor layer disposed on the buffer layer;
An active layer disposed on the first conductivity type semiconductor layer;
A second conductivity type semiconductor layer disposed on the active layer;
A plurality of compound semiconductor layers disposed on the second conductive semiconductor layer and including a first material;
A second material layer comprising a second material different from the first material and disposed on the second conductivity type semiconductor layer and disposed between the plurality of compound semiconductor layers; And
An electrode layer disposed on the compound semiconductor layer and the second material layer and including an ohmic layer;
The compound semiconductor layer is in ohmic contact with the ohmic layer of the electrode layer,
The plurality of compound semiconductor layers are disposed spaced apart from each other by a predetermined distance,
The first material of the compound semiconductor layer has a bandgap energy smaller than that of the second conductive semiconductor layer,
The height of the compound semiconductor layer and the second material layer is the same,
A side surface of the compound semiconductor layer is in direct contact with a side surface of the second material layer,
The overall width of the plurality of compound semiconductor layers is 1 to 9 times the total width of the second material layer,
The second material layer is a transmissive layer,
The permeable layer may be indium tin oxide (ITO), aluminum zinc oxide (AZO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), or indium aluminum zinc IAZO. oxide), 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 And at least one of Ni / IrO _x / Au / ITO. The method of claim 1,
The upper surface of the compound semiconductor layer and the upper surface of the second material layer is disposed on the same plane. delete delete delete The method of claim 1,
The second material layer is a light emitting device. The method of claim 6,
The reflective layer includes at least one of aluminum (Al), silver (Ag), nickel (Ni), platinum (Pt), and rhodium (Rh). The method of claim 6,
The reflective layer is a light emitting device in which the first layer and the second layer having different refractive index are alternately stacked. The method of claim 1,
The first material includes at least one of GaN and InGaN. The method of claim 1,
The first conductive semiconductor layer and the second conductive semiconductor layer include Al. delete delete

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