KR102035180B1

KR102035180B1 - Light emitting device

Info

Publication number: KR102035180B1
Application number: KR1020130010620A
Authority: KR
Inventors: 박범두; 김태진; 황선교; 성영운; 홍기용; 김민석; 이상준; 이태용
Original assignee: 엘지이노텍 주식회사
Priority date: 2013-01-30
Filing date: 2013-01-30
Publication date: 2019-10-22
Also published as: KR20140097899A

Abstract

The light emitting device according to the embodiment includes a conductive substrate; A first electrode layer disposed on the conductive substrate; A window layer disposed on the first electrode layer; A light emitting structure including a first semiconductor layer disposed on the window layer, a second semiconductor layer, and an active layer positioned between the first semiconductor layer and the second semiconductor layer; And a second electrode layer electrically connected to the second semiconductor layer, wherein the first electrode layer comprises a transparent electrode layer disposed between the conductive substrate and the window layer; An ohmic layer having a plurality of metal contact portions disposed on the transparent electrode layer and spaced apart from each other, wherein the metal contact portion has at least one surface in contact with the window layer, and the window layer is in a region where the metal contact portion is in contact with the first semiconductor. A doped region doped with a dopant of the same polarity as the polarity of the layer.

Description

Light emitting device

The embodiment relates to a light emitting device.

As a representative example of a light emitting device, an LED (Light Emitting Diode) is a device that converts an electrical signal into a form of infrared rays, visible rays or light using characteristics of a compound semiconductor. It is used in automation equipment and the like, and the use area of LED is gradually increasing.

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 becomes wider as described above, the luminance required for electric light used for living, electric light for rescue signals, etc. is increased, and it is important to increase the luminance of the LED.

In addition, the electrode of the light emitting device should be excellent in adhesive strength and excellent electrical properties.

In addition, research is being conducted to increase the luminance of the light emitting device and to reduce the voltage used.

The embodiment provides a light emitting device that lowers the VF and improves the light emitting efficiency.

The light emitting device according to the embodiment is doped with impurities only in the region where the metal contact portion is in contact with the window layer, and thus has an advantage of forming ohmic contact without significantly reducing the light efficiency.

Since the metal contact portion is disposed through the transparent electrode layer, there is an advantage that the ohmic contact with the light emitting structure is easy.

In addition, since the metal contact portion penetrates the transparent electrode layer, heat generated in the light emitting structure is easily discharged to the conductive substrate.

In addition, since the metal contact portion is in direct contact with the light emitting structure, there is an advantage that the voltage forward (VF) is reduced.

Since the area of the metal contact portion is smaller than that of the transparent electrode layer, the probability of obstructing the progress of light reflected from the metal reflective layer is reduced, thereby improving luminous efficiency.

1 is a cross-sectional view showing a light emitting device according to an embodiment of the present invention;
FIG. 2 is a cross-sectional plan view of the ohmic layer taken along line AA of FIG. 1;
2 is a cross-sectional view showing a light emitting device according to another embodiment of the present invention;
4 is a cross-sectional view showing a light emitting device according to another embodiment of the present invention;
5 to 10 are explanatory views showing a method of manufacturing a light emitting device according to the embodiment;
11 is a perspective view of a light emitting device package including a light emitting device according to the embodiment;
12 is a cross-sectional view of a light emitting device package including a light emitting device according to the embodiment;
13 is a perspective view illustrating a lighting system including a light emitting device according to the embodiment;
14 is a cross-sectional view showing a CC ′ section of the lighting system of FIG. 13;
15 is an exploded perspective view of a liquid crystal display device including the light emitting device according to the embodiment; and
16 is an exploded perspective view of a liquid crystal display including the light emitting device according to the 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 of a light emitting device according to an embodiment, and FIG. 2 is a plan cross-sectional view of an ohmic layer taken along line A-A of FIG. 1.

Referring to FIG. 1, the light emitting device 100 according to the embodiment may include a conductive substrate 110, a first electrode layer 120 disposed on the conductive substrate 110, and a window layer disposed on the first electrode layer 120. 130, the first semiconductor layer 141 disposed on the first electrode layer 120, the second semiconductor layer 145, and an active layer positioned between the first semiconductor layer 141 and the second semiconductor layer 145. A light emitting structure 140 having a 143; And a second electrode layer 150 electrically connected to the second semiconductor layer 145.

The conductive substrate 110 may support the light emitting structure 140 and provide power to the light emitting structure 140 together with the second electrode layer 150. The conductive substrate 110 may be formed of a material having excellent thermal conductivity or a conductive material, for example, gold (Au), nickel (Ni), tungsten (W), molybdenum (Mo), copper (Cu), or aluminum. (Al), tantalum (Ta), silver (Ag), platinum (Pt), chromium (Cr), silicon (Si), germanium (Ge), gallium (Ga), aceanide (As), zinc (Zn), If it is formed of any one selected from, or formed of two or more alloys may be formed of at least one oxide or nitride of these. In addition, it may include any one selected from Ga 2 O 3 or SiC, SiGe, CuW, it may be formed by stacking two or more different materials. That is, the conductive substrate 110 may be implemented as a carrier wafer.

The conductive substrate 110 may facilitate the emission of heat generated from the light emitting device 100 to improve the thermal stability of the light emitting device 100.

In an embodiment, the conductive substrate 110 is described as having conductivity, but may not have conductivity, but is not limited thereto.

The conductive substrate 110 includes a first electrode layer 120 for supplying power to the light emitting structure 140. Detailed description of the first electrode layer 120 will be described later.

A window layer 130 may be further included on the first electrode layer 120 to reduce a difference in reflectance between the first electrode layer 120 and the light emitting structure 140.

The window layer 130 reduces the difference in reflectance between the light emitting structure 140 and the first electrode layer 120 to prevent total reflection of light passing through the window layer 130, thereby increasing light extraction efficiency.

The window layer 130 may include any one of GaP, GaAsP, and AlGaAs.

The light emitting structure 140 includes a first semiconductor layer 141, a second semiconductor layer 145, and an active layer 143 between the first semiconductor layer 141 and the second semiconductor layer 145.

The second semiconductor layer 145 may be implemented as an n-type semiconductor layer, and the n-type semiconductor layer may be, for example, In _x Al _y Ga _1-xy N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ x a semiconductor material having a compositional formula of + y ≦ 1), for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, and the like, and for example, n, such as Si, Ge, Sn, Se, Te, etc. Type dopants may be doped. In addition, the second semiconductor layer 145 may be selected from a semiconductor material having a compositional formula of (Al _X Ga _1-X ) _0.5 In _0.5 P.

Meanwhile, a second electrode layer 150 electrically connected to the second semiconductor layer 145 may be disposed on the second semiconductor layer 145, and the second electrode layer 150 may have at least one pad or / and a predetermined pattern. It may include an electrode having. The second electrode layer 150 may be disposed in the center region, the outer region, or the corner region of the upper surface of the second semiconductor layer 145, but is not limited thereto. The second electrode layer 150 may be disposed in an area other than the second semiconductor layer 145, but is not limited thereto.

The second electrode layer 150 is a conductive material, for example, In, Co, Si, Ge, Au, Pd, Pt, Ru, Re, Mg, Zn, Hf, Ta, Rh, Ir, W, Ti, Ag, Cr , Mo, Nb, Al, Ni and Cu, it can be formed in a single layer or multiple layers using a metal or alloy selected from.

Concave-convex pattern 160 may be formed in a portion of the entire surface of the second semiconductor layer 145 on which the second electrode layer 150 is not formed or to improve the light extraction efficiency by a predetermined etching method.

Here, the second electrode layer 150 is described as being formed on a flat surface on which the uneven pattern 160 is not formed, but may be formed on the upper surface on which the uneven pattern 160 is formed, but is not limited thereto.

The uneven pattern 160 may be formed by performing etching on at least one region of the upper surface of the second semiconductor layer 145, but is not limited thereto. The etching process includes a wet or / and dry etching process. The uneven pattern 160 formed by etching may be irregularly formed in a random size, but is not limited thereto. The uneven pattern 160 is an uneven upper surface and may include at least one of regular irregularities and irregular irregularities.

Concave-convex pattern 160 may be formed so that the side cross section has a variety of shapes, such as cylinder, polygonal pillar, cone, polygonal pyramid, truncated cone, polygonal truncated cone.

The uneven pattern 160 may be formed by a method such as photo electrochemical (PEC), but is not limited thereto. As the uneven pattern 160 is formed on the upper surface of the second semiconductor layer 145, light generated from the active layer 143 may be totally reflected from the upper surface of the second semiconductor layer 145 to be prevented from being absorbed or scattered again. As a result, the light extraction efficiency of the light emitting device 100 may be improved.

An active layer 143 may be formed under the second semiconductor layer 145. The active layer 143 is a region where electrons and holes are recombined. The active layer 143 transitions to a low energy level as the electrons and holes recombine, and may generate light having a corresponding wavelength.

The active layer 143 may include, for example, a semiconductor material having a compositional formula of In _x Al _y Ga _1-xy N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ x + y ≦ 1). It may be formed of a single quantum well structure or a multi quantum well structure (MQW). In addition, the active layer 143 may be selected from a semiconductor material having a composition formula of (Al _X Ga _1-X ) _0.5 In _0.5 P.

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 first semiconductor layer 141 may be formed under the active layer 143. The first semiconductor layer 141 may be implemented as a p-type semiconductor layer to inject holes into the active layer 143. For example, the p-type semiconductor layer is a semiconductor material having a composition formula of In _x Al _y Ga _1-xy N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ x + y ≦ 1), for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN and the like may be selected, and p-type dopants such as Mg, Zn, Ca, Sr, Ba, and C may be doped. In addition, the first semiconductor layer 141 may be selected from a semiconductor material having a composition formula of (Al _X Ga _1-X ) _0.5 In _0.5 P.

In addition, a third semiconductor layer (not shown) may be formed under the first semiconductor layer 141. The third semiconductor layer may be implemented as a semiconductor layer having a polarity opposite to that of the second semiconductor layer.

Meanwhile, the above-described second semiconductor layer 145, the active layer 143, and the first semiconductor layer 141 may be formed of metal organic chemical vapor deposition (MOCVD), chemical vapor deposition (CVD), and plasma. Plasma-Enhanced Chemical Vapor Deposition (PECVD), Molecular Beam Epitaxy (MBE), Hydride Vapor Phase Epitaxy (HVPE), Sputtering But it is not limited thereto.

In addition, unlike the above-described embodiments, the second semiconductor layer 145 may be implemented as a p-type semiconductor layer, and the first semiconductor layer 141 may be implemented as an n-type semiconductor layer. Accordingly, the light emitting structure 140 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.

In addition, the passivation 170 may be formed to protect a portion or the entire region of the outer circumferential surface of the light emitting structure 140 from external impact, and to prevent electrical short.

1 and 2, the first electrode layer 120 may selectively use a metal and a transparent conductive layer, and provide power to the light emitting structure 140. The first electrode layer 120 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.

The first electrode layer 120 may include at least one of an ohmic layer 123 and an metal reflective layer 125. In addition, the first electrode layer 120 may include at least one of an ohmic layer 123, a metal reflective layer 125, and a metal adhesive layer 121.

For example, the first electrode layer 120 may have a form in which the ohmic layers 123 are sequentially stacked on the metal adhesive layer 121. In FIG. 1, the ohmic layer 123 is stacked on the metal adhesive layer 121.

The ohmic layer 123 is in contact with the window layer 130 or the first semiconductor layer 141. The ohmic layer 123 is a transparent electrode layer 123A disposed between the conductive substrate 110 and the light emitting structure 140, and is transparent. The electrode layers 123A may be provided with a plurality of metal contact portions 123B spaced apart from each other.

The transparent electrode layer 123A may be a material having conductivity while light reflected from the conductive substrate 110 or the metal reflective layer 125 is transmitted. For example, the transparent electrode layer 123A may include at least one of In ₂ O ₃ , SnO ₂ , ZnO, ITO, CTO, CuAlO ₂ , CuGaO _2, and SrCu ₂ O ₂ .

A plurality of metal contact portions 123B are spaced apart from each other in the transparent electrode layer 123A. The plurality of metal contact portions 123B are spaced apart from each other regularly or regularly. The metal contact portion 123B may be in ohmic contact with the light emitting structure 140. At least one surface of the metal contact portion 123B is disposed to contact the window layer 130.

In other words, a plurality of metal contact portions 123B may have a dot or island shape in the transparent electrode layer 123A, and one surface of the metal contact portions 123B may be disposed in contact with the window layer 130. In addition, the other surface of the metal contact portion 123B may be disposed to contact the transparent electrode layer 123A. However, the other surface of the metal contact portion 123B may be in contact with the conductive substrate 110 through the transparent electrode layer 123A. This will be described later.

The metal contact portion 123B may include a metal material having excellent conductivity. For example, the metal contact portion 123B may include Au or Au alloys (AuBe, AuGe).

In this case, the window layer 130 may be formed with a doped region 133 doped with an impurity in a region where the metal contact portion 123B contacts.

The doped region 133 is formed in a region where the metal contact portion 123B is in contact with the window layer 130, and is preferably doped with a dopant having the same polarity as that of the first semiconductor layer 141. Since the first semiconductor layer 141 is doped with a p-type dopant, the doping region 133 will be described based on being doped with a p-type dopant. Although the transmittance decreases, the ability to make ohmic adhesion with the metal contact portion 123B is increased. Therefore, since the doped region 133 is formed only in the region in contact with the metal contact portion 123B in the window layer 130, the window layer 130 and the metal contact portion 123B are in ohmic contact. In addition, the doped region 133 is reduced in the window layer 130, so that light transmittance is not significantly reduced. As a result, the formation of the doped region 133 in the window layer 130 may make ohmic contact between the window layer 130 and the metal contact portion 123B without significantly lowering the light transmittance of the window layer 130. To make it possible. Therefore, the window layer 130 and the metal contact portion 123B are in ohmic contact, so that the operating voltage of the light emitting device 100 is lowered, and the light transmittance of the window layer 130 does not decrease much. There is an advantage.

The p-type dopant doped in the doped region 133 of the window layer 130 may include any one of Mg, Zn, Ca, Sr, Ba, and C.

When the doped region 133 is doped at an excessively high concentration, the light transmittance may be significantly reduced, and when the doped region is too low, ohmic contact between the window layer 130 and the metal contact portion 123B may be difficult. Therefore, when the doped region 133 is doped by Mg, the doping concentration is 5e ¹⁸ / cm ³ to 1e ¹⁸ / cm ³ , and when doped by C, the doping concentration is 5e ¹⁹ / cm ³ to 1e ¹⁹ / It is preferred that it is cm ³ .

The doped regions 133 are spaced apart from each other in a dot or island shape on the window layer 130. Since the arrangement of the doped region 133 corresponds to the arrangement of the metal contact portion 123B, only the metal contact portion 123B will be described below.

The doped region 133 may be formed to a predetermined depth on the surface of the window layer 130. In addition, the doped region 133 may protrude from the surface of the window layer 130. That is, in the process of doping the entire surface of the window layer 130 and etching the region except the doped region 133, the surface of the window layer 130 is etched to form the surface of the window layer 130 of the doped region 133. Can protrude from However, the present invention is not limited thereto.

In particular, referring to FIG. 2, the planar area of the transparent electrode layer 123A is preferably greater than the planar area of the metal contact portion 123B, and more preferably, the planar area of the metal contact portion 123B is transparent. The electrode layer 123A may be in a range of about 10% to about 25% of the area of the plane. When the planar area of the metal contact portion 123B is smaller than 10% of the planar area of the transparent electrode layer 123A, the ohmic contact between the light emitting structure 140 and the first electrode layer 120 is difficult, and the metal contact portion 123B is inferior. If the planar area is larger than 25% of the planar area of the transparent electrode layer 123A, the light efficiency of the light emitting device 100 is lowered due to the metal contact portion 123B having a low light transmittance.

The planar area of the doped region 133 is formed to be the same as the planar area of the metal contact portion 123B described above. If the planar area of the doped region 133 is too small, it is difficult for the window layer 130 and the metal contact portion 123B to make ohmic contact, and if too large, the light effect of the light emitting device is greatly reduced.

If the planar area of the metal contact portion 123B is 10% to 25% of the planar area of the transparent electrode layer 123A, for example, the distance between the adjacent metal contact portions 123B is between 35 µm and 500 mm. It is preferable that the thickness of the metal contact portion 123B is from 10 μm to 20 μm. Of course, the separation distance between the doped regions 133 adjacent to each other may also be the same as the separation distance between the metal contact portions 123B.

The metal contact portion 123B is not limited in shape, but may have a rod shape. Preferably, the metal contact portion 123B has a shape of a cylinder or a polygonal column.

The first electrode layer 120 may be flat as shown in FIG. 1, but is not limited thereto and may have a step.

The first electrode layer 120 may further include a rapid bonding layer 121.

The quick bonding layer 121 may be formed under the ohmic layer 123 to enhance the adhesion between the layers. The quick bonding layer 121 may be formed using a material having excellent adhesion to the underlying material. For example, it may include any one of PbSn alloy, AuGe alloy, AuBe alloy, AuSn alloy, Sn, In and PdIn alloy. Also,

A diffusion barrier layer (not shown) may be further formed on the quick bonding layer 121. The diffusion barrier layer may prevent the material forming the conductive substrate 110 and the quick bonding layer 121 from being diffused into the light emitting structure 140. The diffusion barrier layer may be formed of a material that prevents diffusion of metals. For example, platinum (Pt), palladium (Pd), tungsten (W), nickel (Ni), ruthenium (Ru), molybdenum (Mo), At least one or two or more alloys of iridium (Ir), rhodium (Rh), tantalum (Ta), hafnium (Hf), zirconium (Zr), niobium (Nb), and vanadium (V) may be used. However, it is not limited thereto. The quick bonding layer 121 may be formed in a single layer or a multilayer structure.

3 is a cross-sectional view showing a light emitting device according to another embodiment of the present invention.

Referring to FIG. 3, in the light emitting device 100A according to the embodiment, the metal contact portion 123B is formed to penetrate the transparent electrode layer 123A as compared with the embodiment of FIG. 1.

The metal contact portion 123B penetrates through the transparent electrode layer 123A, and one surface thereof is in contact with the window layer 130, and the other surface thereof is in contact with the conductive substrate 110 or the quick bonding layer 121.

When the metal contact portion 123B is disposed through the transparent electrode layer 123A, ohmic contact with the light emitting structure 140 may be easily performed. In addition, since the metal contact portion 123B penetrates the transparent electrode layer 123A, heat generated in the light emitting structure 140 may be easily discharged to the conductive substrate 110.

In addition, since the metal contact portion 123B is in direct contact with the light emitting structure 140, there is an advantage that the voltage forward (VF) is reduced. In particular, since the conductivity of the transparent electrode layer 123A is lower than that of the metal contact portion 123B, the use voltage of about 10% is lowered compared to the case where the metal contact portion 123B does not penetrate the transparent electrode layer 123A. Have

4 is a cross-sectional view showing a light emitting device according to another embodiment of the present invention.

Referring to FIG. 4, the light emitting device 100B according to the embodiment further includes a metal reflective layer 125 and a current blocking layer 180 as compared with the embodiment of FIG. 1.

The first electrode layer 120 further includes a metal reflective layer 125. The metal reflective layer 125 is formed under the ohmic layer 123 to reflect the light directed toward the conductive substrate 110 among the light reflected by the active layer 143 to the upper portion of the light emitting structure 140.

The metal reflective layer 125 may be formed from a material having excellent reflective properties, such as Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, Hf, and a combination thereof. It may be formed in a multilayer using a metal material and a light transmitting conductive material such as IZO, IZTO, IAZO, IGZO, IGTO, AZO, ATO. In addition, the reflective layer (not shown) may be laminated with IZO / Ni, AZO / Ag, IZO / Ag / Ni, AZO / Ag / Ni, or the like.

The current blocking layer 180 is disposed to overlap at least one region in the vertical direction with the second electrode layer 150 under the light emitting structure 140, and has lower electrical conductivity than the ohmic layer 123 and the metal reflective layer 125. Can be. The current blocking layer 180 may include, for example, aluminum oxide (Al ₂ O ₃ ), silicon oxide (SiO ₂ ), silicon nitride (Si ₃ N ₄ ), titanium oxide (TiO _x ), indium tin oxide (ITO, Indium). Tin Oxide), aluminum zinc oxide (AZO), and indium zinc oxide (IZO). However, the present invention is not limited thereto.

The current blocking layer 180 prevents electrons injected into the active layer 143 from the second semiconductor layer 145 when the high current is applied to the first electrode layer 120 without recombination in the active layer 143. It may be an blocking layer. The current blocking layer 180 has a larger band gap than the active layer 143, so that electrons injected from the second semiconductor layer 145 do not recombine in the active layer 143 to the first semiconductor layer 141. Injection phenomenon can be prevented. Accordingly, the probability of recombination of electrons and holes in the active layer 143 may be increased and leakage current may be prevented.

5 to 10 are flowcharts illustrating a manufacturing process of the light emitting device of FIG. 1.

The light emitting device manufacturing method according to the embodiment is as follows.

Referring to FIG. 5, first, a light emitting structure 140 including a second semiconductor layer 145, an active layer 143, and a first semiconductor layer 141 is sequentially stacked on the growth substrate 101.

The growth substrate 101 may be selected from the group consisting of sapphire substrate (Al ₂ 0 ₃ ), GaN, SiC, ZnO, Si, GaP, InP, GaAs, and the like. A buffer layer (not shown) may be formed between the light emitting structures 140.

The buffer layer (not shown) may have a form in which Group 3 and Group 5 elements are combined, 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 (not shown) may be formed on the growth substrate 101 or the buffer layer (not shown), and either or both of the buffer layer and the undoped semiconductor layer (not shown) may be formed. It may or may not be formed and is not limited to this structure.

Referring to FIG. 6, the window layer 130 is disposed on the light emitting structure 140.

Thereafter, the surface of the window layer 130 is doped with impurities.

The PR (Photo Resist) 10 having a predetermined pattern may be disposed on the window layer 130. In this case, the PR 10 may be disposed in a predetermined pattern corresponding to the metal contact portion 123B in consideration of current spreading and light extraction efficiency.

Thereafter, an area other than the area vertically overlapping with the area where the PR 10 is disposed in the window layer 130 is removed. Accordingly, the doped region 133 is formed in the window layer 130.

Referring to FIG. 7, the PR 10 is removed and a transparent electrode layer 123A is formed on the window layer 130.

A PR (Photo Resist) 10 having a predetermined pattern may be disposed on the transparent electrode layer 123A. In this case, the PR 10 may be disposed in a predetermined pattern corresponding to the metal contact portion 123B in consideration of current spreading and light extraction efficiency.

Thereafter, regions other than the region vertically overlapping with the region where the PR 10 is disposed in the transparent electrode layer 123A are removed. In this case, the cross section to be removed may form a rectangle, and may have a curvature or a step. It does not limit to this. The removal method may be a wet etching, dry etching, or laser lift off method, but is not limited thereto.

Referring to FIG. 8, the PR 10 may be removed and a metal contact portion 123B may be formed in the etched region.

Referring to FIG. 9, the conductive substrate 110 on which the metal adhesive layer 121 is disposed is bonded and bonded, and the growth substrate 101 disposed on the second semiconductor layer 145 may be separated.

In this case, the growth substrate 101 may be removed by physical or / and chemical methods, and the physical method may be removed by, for example, a laser lift off (LLO) method.

Referring to FIG. 10, the passivation 170 may be formed on a part or the entire area of the outer circumferential surface of the light emitting structure 140.

In addition, the concave-convex pattern 160 may be formed on a portion or the entire surface of the second semiconductor layer 145 of the light emitting structure 140 by a predetermined etching method, and the surface of the second semiconductor layer 145 may be formed. The second electrode layer 150 is formed on the substrate.

In addition, at least one process in the process sequence shown in FIGS. 5 to 10 may be reversed, but the present invention is not limited thereto.

11 is a perspective view showing a light emitting device package including a light emitting device according to the embodiment, Figure 12 is a cross-sectional view showing a light emitting device package including a light emitting device according to the embodiment.

11 and 12, the light emitting device package 500 includes a body 510 having a cavity 520, first and second lead frames 540 and 550 mounted on the body 510, and a first one. And a light emitting device 530 electrically connected to the second lead frames 540 and 550, and an encapsulant (not shown) filled in the cavity 520 to cover the light emitting device 530.

The body 510 is made of a resin material such as polyphthalamide (PPA), silicon (Si), aluminum (Al), aluminum nitride (AlN), photosensitive glass (PSG), polyamide 9T (PA9T) ), Neo geotactic polystyrene (SPS), a metal material, sapphire (Al ₂ O ₃ ), beryllium oxide (BeO), may be formed of at least one of a printed circuit board (PCB, Printed Circuit Board). The body 510 may be formed by injection molding, etching, or the like, but is not limited thereto.

An inner surface of the body 510 may be formed with an inclined surface. The angle of reflection of the light emitted from the light emitting device 530 may vary according to the angle of the inclined surface, thereby adjusting the directivity angle of the light emitted to the outside.

As the directivity of the light decreases, the concentration of light emitted from the light emitting device 530 to the outside increases. On the contrary, the greater the directivity of the light, the less the concentration of light emitted from the light emitting device 530 to the outside.

On the other hand, the shape of the cavity 520 formed on the body 510 as viewed from above may be circular, rectangular, polygonal, elliptical, or the like, and may have a curved edge, but is not limited thereto.

The light emitting device 530 is mounted on the first lead frame 540 and may be, for example, a light emitting device emitting light of red, green, blue, white, or UV (ultraviolet) light emitting device emitting ultraviolet light. But it is not limited thereto. In addition, one or more light emitting devices 530 may be mounted.

In addition, the light emitting device 530 may be a horizontal type in which all of its electrical terminals are formed on an upper surface, or a vertical type or flip chip formed on an upper and a lower surface. Applicable

An encapsulant (not shown) may be filled in the cavity 520 to cover the light emitting device 530.

The encapsulant (not shown) may be formed of silicon, epoxy, and other resin materials, and may be formed by filling the cavity 520 and then UV or heat curing the same.

In addition, the encapsulant (not shown) may include a phosphor, and the phosphor may be selected from a wavelength of light emitted from the light emitting device 530 so that the light emitting device package 500 may realize white light.

The phosphor is one of a blue light emitting phosphor, a blue green light emitting phosphor, a green light emitting phosphor, a yellow green light emitting phosphor, a yellow light emitting phosphor, a yellow red light emitting phosphor, an orange light emitting phosphor, and a red light emitting phosphor according to the wavelength of light emitted from the light emitting element 530. Can be applied.

That is, the phosphor may be excited by light having the first light emitted from the light emitting device 530 to generate the second light. For example, when the light emitting element 530 is a blue light emitting diode and the phosphor is a yellow phosphor, the yellow phosphor may be excited by blue light to emit yellow light, and the blue light and blue light generated by the blue light emitting diode As the generated yellow light is mixed, the light emitting device package 500 may provide white light.

Similarly, when the light emitting element 530 is a green light emitting diode, a magenta phosphor or a mixture of blue and red phosphors is mixed. When the light emitting element 530 is a red light emitting diode, a cyan phosphor or a blue and green phosphor is used. For example,

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

The first and second lead frames 540 and 550 are made of a metal material, for example, titanium (Ti), copper (Cu), nickel (Ni), gold (Au), chromium (Cr), and tantalum (Ta). , Platinum (Pt), tin (Sn), silver (Ag), phosphorus (P), aluminum (Al), indium (In), palladium (Pd), cobalt (Co), silicon (Si), germanium (Ge) It may include one or more materials or alloys of hafnium (Hf), ruthenium (Ru), iron (Fe). In addition, the first and second lead frames 540 and 550 may be formed to have a single layer or a multilayer structure, but the embodiment is not limited thereto.

The first second lead frames 540 and 550 are spaced apart from each other and electrically separated from each other. The light emitting device 530 is mounted on the first and second lead frames 540 and 550, and the first and second lead frames 540 and 550 are in direct contact with the light emitting device 530 or a soldering member (not shown). May be electrically connected through a material having conductivity such as C). In addition, the light emitting device 530 may be electrically connected to the first and second lead frames 540 and 550 through wire bonding, but is not limited thereto. Therefore, when power is connected to the first and second lead frames 540 and 550, power may be applied to the light emitting device 530. Meanwhile, several lead frames (not shown) may be mounted in the body 510, and each lead frame (not shown) may be electrically connected to the light emitting device 530, but is not limited thereto.

FIG. 13 is a perspective view illustrating a lighting apparatus including a light emitting device according to an embodiment, and FIG. 14 is a cross-sectional view illustrating a C-C 'cross section of the lighting apparatus of FIG.

13 and 14, the lighting device 600 may include a body 610, a cover 630 fastened to the body 610, and a closing cap 650 located at both ends of the body 610. have.

The light emitting device module 640 is fastened to the lower surface of the body 610, and the body 610 is conductive so that heat generated in the light emitting device package 644 can be discharged to the outside through the upper surface of the body 610. And it may be formed of a metal material having an excellent heat dissipation effect.

The light emitting device package 644 may be mounted on the PCB 642 in a multi-colored, multi-row array to form an array. The light emitting device package 644 may be mounted at the same interval or may be mounted with various separation distances as necessary to adjust brightness. The PCB 642 may be a metal core PCB (MPPCB) or a PCB made of FR4.

Since the light emitting device package 644 may have an improved heat dissipation function including an extended lead frame (not shown), reliability and efficiency of the light emitting device package 644 may be improved, and the light emitting device package 622 and the light emitting device may be improved. The service life of the lighting device 600 including the device package 644 may be extended.

The cover 630 may be formed in a circular shape to surround the lower surface of the body 610, but is not limited thereto.

The cover 630 protects the light emitting device module 640 from the outside and the like. In addition, the cover 630 may include diffusing particles to prevent glare of the light generated from the light emitting device package 644, 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 630. 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 630.

On the other hand, since the light generated from the light emitting device package 644 is emitted to the outside through the cover 630, the cover 630 should have excellent light transmittance, and has sufficient heat resistance to withstand the heat generated from the light emitting device package 644. The cover 630 is preferably formed of a material including polyethylene terephthalate (PET), polycarbonate (PC), polymethyl methacrylate (PMMA), or the like. .

Closing cap 650 is located at both ends of the body 610 may be used for sealing the power supply (not shown). In addition, the closing cap 650, the power pin 652 is formed, the lighting device 600 according to the embodiment can be used immediately without a separate device in the terminal removed the existing fluorescent lamp.

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

FIG. 15 illustrates an edge-light method. The LCD 700 may include a liquid crystal display panel 710 and a backlight unit 770 for providing light to the liquid crystal display panel 710.

The liquid crystal display panel 710 may display an image using light provided from the backlight unit 770. The liquid crystal display panel 710 may include a color filter substrate 712 and a thin film transistor substrate 714 facing each other with a liquid crystal interposed therebetween.

The color filter substrate 712 may implement a color of an image displayed through the liquid crystal display panel 710.

The thin film transistor substrate 714 is electrically connected to the printed circuit board 718 on which a plurality of circuit components are mounted through the driving film 717. The thin film transistor substrate 714 may apply a driving voltage provided from the printed circuit board 718 to the liquid crystal in response to a driving signal provided from the printed circuit board 718.

The thin film transistor substrate 714 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 770 may include a light emitting device module 720 for outputting light, a light guide plate 730 for changing the light provided from the light emitting device module 720 into a surface light source, and providing the light to the liquid crystal display panel 710. Reflective sheet for reflecting the light emitted from the back of the light guide plate 730 and the plurality of films 752, 766, 764 to uniform the luminance distribution of the light provided from the 730 and improve the vertical incidence ( 747).

The light emitting device module 720 may include a PCB substrate 722 such that a plurality of light emitting device packages 724 and a plurality of light emitting device packages 724 are mounted to form an array. In this case, reliability of mounting the curved light emitting device package 724 may be improved.

Meanwhile, the backlight unit 770 includes a diffusion film 766 that diffuses light incident from the light guide plate 730 toward the liquid crystal display panel 710, and a prism film 752 that concentrates the diffused light to improve vertical incidence. It may be configured as), and may include a protective film 764 for protecting the prism film 750.

16 is an exploded perspective view of a liquid crystal display including the light emitting device according to the embodiment. However, the parts shown and described in FIG. 15 will not be repeatedly described in detail.

16 is a direct view, the liquid crystal display device 800 may include a liquid crystal display panel 810 and a backlight unit 870 for providing light to the liquid crystal display panel 810.

Since the liquid crystal display panel 810 is the same as that described with reference to FIG. 15, a detailed description thereof will be omitted.

The backlight unit 870 includes a plurality of light emitting device modules 823, a reflective sheet 824, a lower chassis 830 in which the light emitting device modules 823 and the reflective sheet 824 are accommodated, and an upper portion of the light emitting device module 823. It may include a diffusion plate 840 and a plurality of optical film 860 disposed in the.

LED Module 823 A plurality of light emitting device packages 822 and a plurality of light emitting device packages 822 may be mounted to include a PCB substrate 821 to form an array.

The reflective sheet 824 reflects light generated from the light emitting device package 822 in the direction in which the liquid crystal display panel 810 is located to improve light utilization efficiency.

Meanwhile, light generated by the light emitting device module 823 is incident on the diffusion plate 840, and the optical film 860 is disposed on the diffusion plate 840. The optical film 860 may include a diffusion film 866, a prism film 850, and a protective film 864.

In addition, the above description has been made with reference to the embodiment, which is merely an example, and is not intended to limit the present invention. Those skilled in the art to which the present invention pertains will be illustrated as above without departing from the essential characteristics of the present embodiment. Many variations and applications are available. For example, each component specifically shown in the embodiment can be modified. And differences relating to such modifications and applications will have to be construed as being included in the scope of the invention defined in the appended claims.

Claims

Conductive substrates;
A first electrode layer disposed on the conductive substrate;
A window layer disposed on the first electrode layer;
A light emitting structure including a first semiconductor layer disposed on the window layer, a second semiconductor layer, and an active layer positioned between the first semiconductor layer and the second semiconductor layer; And
A second electrode layer electrically connected to the second semiconductor layer;
The first electrode layer,
A transparent electrode layer disposed between the conductive substrate and the window layer;
An ohmic layer having a plurality of metal contact parts disposed on the transparent electrode layer and spaced apart from each other,
At least one surface of the metal contact portion contacts the window layer,
The window layer includes a doped region doped with a dopant having the same polarity as that of the first semiconductor layer in a region where the metal contact portion is in contact with the window contact layer.
And the doped region is formed only in a region of the window layer which contacts the metal contact portion.

The method of claim 1,
The transparent electrode layer,
A light emitting device comprising at least one of In ₂ O ₃ , SnO ₂ , ZnO, ITO, CTO, CuAlO ₂ , CuGaO _2, and SrCu ₂ O ₂ .

The method of claim 1,
The planar area of the transparent electrode layer is larger than the planar area of the metal contact portion.

The method of claim 1,
The window layer comprises a light emitting element comprising any one of GaP, GaAsP and AlGaAs.

The method of claim 1,
The metal contact portion,
A light emitting device penetrating the transparent electrode, the other surface is in contact with the conductive substrate.

The method of claim 1,
The metal contact portion is a light emitting device having a cylindrical or polygonal shape.

The method of claim 1,
Wherein the first semiconductor layer is doped with an n-type dopant, and the second semiconductor layer is doped with an n-type dopant.

The method of claim 1,
The light emitting structure
A light emitting element comprising Alkya NP or BAyNP.

The method of claim 1,
And the doped region is doped with a p-type dopant.

The method of claim 9,
The p-type dopant is a light emitting device containing any one of Mg, Zn, Ca, Sr, Ba and C.

The method of claim 1,
The doped region protrudes from the surface of the window layer.

The method of claim 1,
The metal contact portion includes Au or Au alloy.

The method of claim 1,
The first electrode layer is,
A light emitting device, further comprising a metal bonding layer disposed below the ohmic layer.

The method of claim 1,
The first electrode layer is,
The light emitting device further comprises a metal reflective layer disposed under the ohmic layer.

The method of claim 1,
The conductive substrate includes any one of Si, Ge, SiC, and AlN.

The method of claim 14,
The metal reflective layer includes any one of Au, Al, Ag, and Ni.

The method of claim 13,
The metal bonding layer is a light emitting device comprising any one of a PbSn alloy, AuGe alloy, AuBe alloy, AuSn alloy, Sn, In and PdIn alloy.

The method of claim 1,
A light emitting element is formed on the upper surface of the second semiconductor layer is an uneven pattern for improving the light extraction efficiency.

The method of claim 1,
2. A light emitting device in which a passivation layer is formed in at least part of an outer circumferential surface of the light emitting structure to isolate the outside.

The method of claim 1,
And at least one region overlapping the second electrode layer in a vertical direction below the light emitting structure, and further comprising a current blocking layer having a lower electrical conductivity than the first electrode layer.

The method of claim 20,
The current blocking layer,
Aluminum oxide (Al ₂ O ₃ ), silicon oxide (SiO ₂ ), silicon nitride (Si ₃ N ₄ ), titanium oxide (TiO _x ), aluminum zinc oxide (AZO) and indium zinc oxide (IZO, Indium Light emitting element comprising at least one of Zinc Oxide.

In the light emitting device package comprising a light emitting device,
The light emitting device,
Conductive substrates;
A first electrode layer disposed on the conductive substrate;
A window layer disposed on the first electrode layer;
A light emitting structure including a first semiconductor layer disposed on the window layer, a second semiconductor layer, and an active layer positioned between the first semiconductor layer and the second semiconductor layer; And
A second electrode layer electrically connected to the second semiconductor layer;
The first electrode layer,
A transparent electrode layer disposed between the conductive substrate and the window layer;
An ohmic layer having a plurality of metal contact parts disposed on the transparent electrode layer and spaced apart from each other,
At least one surface of the metal contact portion contacts the window layer,
The window layer includes a doped region doped with a dopant having the same polarity as that of the first semiconductor layer in a region where the metal contact portion is in contact with the window contact layer.
Wherein the doped region is formed only in a region of the window layer that contacts the metal contact portion.

In a lighting system including a light emitting element,
The light emitting device,
Conductive substrates;
A first electrode layer disposed on the conductive substrate;
A window layer disposed on the first electrode layer;
A light emitting structure including a first semiconductor layer disposed on the window layer, a second semiconductor layer, and an active layer positioned between the first semiconductor layer and the second semiconductor layer; And
A second electrode layer electrically connected to the second semiconductor layer;
The first electrode layer,
A transparent electrode layer disposed between the conductive substrate and the window layer;
An ohmic layer having a plurality of metal contact parts disposed on the transparent electrode layer and spaced apart from each other,
At least one surface of the metal contact portion contacts the window layer,
The window layer includes a doped region doped with a dopant having the same polarity as that of the first semiconductor layer in a region where the metal contact portion is in contact with the window contact layer.
And the doped region is formed only in an area of the window layer in contact with the metal contact portion.

In the backlight unit including a light emitting element,
The light emitting device,
Conductive substrates;
A first electrode layer disposed on the conductive substrate;
A window layer disposed on the first electrode layer;
A light emitting structure including a first semiconductor layer disposed on the window layer, a second semiconductor layer, and an active layer positioned between the first semiconductor layer and the second semiconductor layer; And
A second electrode layer electrically connected to the second semiconductor layer;
The first electrode layer,
A transparent electrode layer disposed between the conductive substrate and the window layer;
An ohmic layer having a plurality of metal contact parts disposed on the transparent electrode layer and spaced apart from each other,
At least one surface of the metal contact portion contacts the window layer,
The window layer includes a doped region doped with a dopant having the same polarity as that of the first semiconductor layer in a region where the metal contact portion is in contact with the window contact layer.
And the doped region is formed only in an area of the window layer in contact with the metal contact portion.