KR20150080838A - Light emitting device - Google Patents

Abstract

A light emitting device according to an embodiment comprises a substrate; a light emitting structure formed on the substrate, and including a first semiconductor layer, a second semiconductor layer, and an active layer placed between the first semiconductor layer and the second semiconductor layer; a current limitation layer formed on a part of area on the second semiconductor layer; a conductive layer formed on the current limitation layer; a second electrode formed on the conductive layer, and having at least one part vertically overlapped with the current limitation layer and the conductive layer; and a transparent conductive layer located on the light emitting structure, and having at least one part vertically overlapped with the current limitation layer and the conductive layer.

Description

[0001]

The embodiment relates to a light emitting device having improved light efficiency.

As a typical example of a light emitting device, a light emitting diode (LED) is a device for converting an electric signal into an infrared ray, a visible ray, or a light using the characteristics of a compound semiconductor, and is used for various devices such as household appliances, remote controllers, Automation equipment, and the like, and the use area of LEDs is gradually widening.

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

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

On the other hand, an electrode is necessarily included in the light emitting device, but the light efficiency is lowered due to the resistance of the electrode. Therefore, efforts must be made to minimize the resistance at the electrode.

Embodiments provide a light emitting device that includes a current confined layer and a conductive layer and improves light efficiency.

A light emitting device according to an embodiment includes a substrate, a light emitting structure formed on the substrate, the light emitting structure including a first semiconductor layer, a second semiconductor layer, and an active layer between the first semiconductor layer and the second semiconductor layer; A current confinement layer formed on a part of the semiconductor layer; a conductive layer formed on the current confinement layer; and a second current confinement layer formed on the conductive layer, wherein at least a part of the current confinement layer and the conductive layer are vertically overlapped with each other An electrode, and a transparent conductive layer which is located on the light emitting structure and in which the current confining layer and the conductive layer are at least partially overlapped with each other in the vertical direction.

The light emitting device according to the embodiment includes the current confining layer and the conductive layer, thereby reducing the resistance generated at the second electrode and lowering the operating voltage.

Also, since the operating voltage is lowered, the light efficiency is improved.

1 is a cross-sectional view illustrating a light emitting device according to an embodiment.
2 is a cross-sectional view illustrating a light emitting device according to another embodiment.
Fig. 3 is an enlarged view of a portion of Fig. 2; Fig.
4 is a graph according to an experimental value referred to for explaining the operating voltage and light efficiency according to the length d1.
5 is a cross-sectional view illustrating a light emitting device package including a light emitting device according to an embodiment.
6 is an exploded perspective view of a display device including a light emitting device according to an embodiment.
7 is a cross-sectional view of the display device of Fig.
8 is an exploded perspective view of a lighting device including a light emitting device according to an embodiment.

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

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

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

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

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

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

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

1, a light emitting device 100 according to an embodiment includes a substrate 110, light emitting structures 130, 140 and 150, a first electrode 135, a current confining layer 170, a conductive layer 180, A transparent conductive layer 160 (TCL), and a second electrode 190.

The substrate 110 is preferably formed using a transparent material including sapphire. In addition to sapphire, the substrate 110 may include zinc oxide (ZnO), gallium nitride (GaN) gallium nitride (GaN), silicon carbide (SiC), silicon and aluminum nitride (AlN).

A buffer layer 120 may be disposed on the substrate 110 to mitigate lattice mismatch between the substrate 110 and the first semiconductor layer 130. The buffer layer 120 can be formed in a low-temperature atmosphere and can be selected from materials such as GaN, InN, AlN, AlInN, InGaN, AlGaN, and InAlGaN.

The first semiconductor layer 130 may be formed on the buffer layer 120. The first semiconductor layer 130 may include a p-type or n-type semiconductor layer.

The n-type semiconductor layer may be a semiconductor material having a composition formula of InxAlyGa1-x-yN (0 = x = 1, 0 = y = 1, 0 = x + y = 1), for example GaN, AlN, AlGaN, InGaN, InN , InAlGaN, AlInN and the like, and an n-type dopant such as Si, Ge or Sn can be doped.

The p-type semiconductor layer is made of a semiconductor material having a composition formula of InxAlyGa1-x-yN (0 = x = 1, 0 = y = 1, 0 = x + y = 1), for example, GaN, AlN, AlGaN, InGaN, InN InAlGaN, AlInN and the like, and a p-type dopant such as Mg, Zn, Ca, Sr, or Ba can be doped.

For example, the first semiconductor layer 130 may be formed using a metal organic chemical vapor deposition (MOCVD) method, a chemical vapor deposition (CVD) method, a plasma enhanced chemical vapor deposition (PECVD) method, ), A molecular beam epitaxy (MBE) method, a hydride vapor phase epitaxy (HVPE) method, and the like, but the present invention is not limited thereto.

The active layer 140 may be formed on the first semiconductor layer 130. The active layer 140 is a region where electrons and holes are recombined. As the electrons and the holes are recombined, the active layer 140 transits to a low energy level and can generate light having a wavelength corresponding thereto.

The active layer 140 may be formed of a semiconductor material having a composition formula of, for example, InxAlyGa1-x-yN (0 = x = 1, 0 = y = 1, 0 = x + y = 1) A quantum well structure or a multi quantum well (MQW) structure. It may also include a quantum wire structure or a quantum dot structure.

The second semiconductor layer 150 may be formed of, for example, a p-type semiconductor layer. The p-type semiconductor layer may be formed of InxAlyGa1-x AlN, AlGaN, InGaN, InN, InAlGaN, AlInN and the like having a composition formula of-yN (0 = x = 1, 0 = y = 1, 0 = x + y = 1) And p-type dopants such as Mg, Zn, Ca, Sr, and Ba can be doped.

A third conductive semiconductor layer (not shown) including an n-type or p-type semiconductor layer may be formed on the first and second semiconductor layers 130 and 150. The light emitting element 100 may include np, pn, npn , and a pnp junction structure.

In addition, the doping concentrations of the conductive dopants in the first semiconductor layer 130 and the second semiconductor layer 150 can be uniformly or nonuniformly formed. That is, the structure of the plurality of semiconductor layers may be variously formed, but the structure is not limited thereto.

In addition, unlike the above, the first semiconductor layer 130 may include a p-type semiconductor layer, and the second semiconductor layer 150 may include an n-type semiconductor layer. That is, the positions of the first semiconductor layer 130 and the second semiconductor layer 150 formed around the active layer 140 may be changed. However, in the following description, the first semiconductor layer 130 includes the n- And is close to the substrate 110. [0035]

The first electrode 135 may be formed in a plurality of positions in consideration of the size of the light emitting device 100. The second electrode 150 may be formed in a part of the active layer 140 A portion of the first semiconductor layer 130 is exposed, and a first electrode 135 is formed on the exposed top surface of the first semiconductor layer 130. When the transparent conductive layer 160 is formed in the light emitting structure, the transparent conductive layer 160, the second semiconductor layer 150, and a part of the active layer 140 are removed, and the exposed first semiconductor layer 130 may have a first electrode 135 formed thereon. However, the present invention is not limited thereto, and the first electrode 135 may be formed on the exposed surface of the first semiconductor layer 130 after the substrate 110 and the buffer layer 120 are removed.

The method of removing the upper surface of the first semiconductor layer 130 is not limited, but wet etching, dry etching, etc. may be used.

The first electrode 170 may be formed of a metal material such as titanium, copper, nickel, gold, chromium, tantalum, platinum, (Al), indium (In), palladium (Pd), cobalt (Co), silicon (Si), germanium (Ge), hafnium (Hf), tin (Sn), silver (Ag) Ruthenium (Ru), and iron (Fe). In addition, the first electrode 170 may have a single-layer structure or a multi-layer structure, but the present invention is not limited thereto.

The current confining layer 170 is formed in a part of the region on the second semiconductor layer 150. The current confining layer 170 (CBL) comprises a nonconductive or weakly conductive material, and may preferably consist of silicon dioxide (SiO2), or aluminum oxide (Al2O3) comprising silicon dioxide (SiO2).

On the other hand, the current confining layer 170 may be a layer having a high reflectance. For example, the current confining layer 170 may be a DBR (Distributed Bragg Reflector) layer.

A conductive layer 180 is formed on the current confining layer 170. The conductive layer 180 may be formed of a metal, a metal alloy, or a conductive semiconductor material having excellent electrical conductivity. For example, the conductive layer 180 may be copper (Cu), copper alloy (Cu Alloy), Si, Mo, SiGe, or the like. The conductive layer 180 may be formed using an electrochemical metal deposition method or a bonding method using a eutectic metal.

On the other hand, the conductive layer 180 may be formed of a metal layer containing aluminum (Al), silver (Ag), rhodium (Rh), or an alloy containing Al or Ag. Aluminum (Al), silver (Ag), rhodium (Rh), and the like can effectively reflect light generated in the active layer and greatly improve light extraction efficiency of the light emitting device.

The second electrode 190 is formed on the conductive layer 180 and at least a part of the current limiting layer 170 and the conductive layer 180 may overlap in the vertical direction.

The second electrode 190 may be formed of a metal material such as titanium, copper, nickel, gold, chromium, tantalum, platinum, (Al), indium (In), palladium (Pd), cobalt (Co), silicon (Si), germanium (Ge), hafnium (Hf), tin (Sn), silver (Ag) Ruthenium (Ru), and iron (Fe). In addition, the second electrode 190 may have a single-layer structure or a multi-layer structure, but the present invention is not limited thereto.

The transparent conductive layer 160 may be positioned on the light emitting structure 130, 140, 150 and at least a portion of the current confined layer 170 and the conductive layer 180 may overlap with each other in the vertical direction.

The transparent conductive layer 160 may be formed of at least one of a transparent conductive oxide (TCO), a transparent conductive nitride (TCN), and a transparent conductive oxide nitride (ITO).

The transparent conductive layer 60 may be formed of a material having a light transmittance of 50% or more and a sheet resistance of 10 Ω / sq or less. The transparent conductive layer 60 may include at least one of In, Sn, Zn, Cd, Ga, Al, Mg, Ti, Mo, Ni, Cu, Ag, Au, Sb, Pt, Rh, Ir, Ru, The material may be formed by bonding with at least one of O and N. [

For example, the transparent conductive oxide may be at least one selected from the group consisting of indium-tin oxide (ITO), zinc oxide (ZnO), aluminum doped zinc oxide (AZO), indium zinc oxide (IZO), antimony tin oxide (ATO) The transparent conductive nitride may be at least one of TiN, CrN, TaN, and In-N, and the transparent conductive oxynitride may be at least one of ITON ( Indium-Tin Oxide Nitride), ZnON, O-In-N, and IZON (Indium Zinc Oxide Nitride).

In general, Ohm's law is that the voltage is proportional to the resistance. Therefore, as the resistance becomes smaller, the voltage becomes lower. The resistance in the conductor is proportional to the length of the conductor and is inversely proportional to the cross-sectional area of the conductor.

The general physical properties may be applied to the second electrode pad 190. For example, when the cross-sectional area of the electrode pad increases, the resistance of the second electrode pad 190 decreases. When the resistance of the second electrode pad 190 is reduced, the operating voltage is reduced and the light efficiency is increased. However, when the cross-sectional area of the second electrode pad 190 is increased, the cost of the light emitting device 100 is increased, and optical loss is increased by an increased area.

According to the embodiment of the present invention, when the light emitting device 100 includes the current confining layer 170 and the conductive layer 180, the area of the second electrode pad 190 is increased. As a result, the effect of reducing the resistance of the second electrode pad 190 occurs. As a result, the operation voltage is reduced and the light efficiency is increased.

Here, when the widths of the current confinement layer 170 and the conductive layer 180 are larger than the width of the second electrode 190, the light efficiency is increased. The description will be made with reference to Figs. 3 to 5. Fig.

FIG. 2 is a cross-sectional view showing a light emitting device according to another embodiment, and FIG. 3 is an enlarged view of an enlarged view of FIG.

The description of the light emitting device 200 according to yet another embodiment, which is the same as the description of FIG. 1, will be omitted.

2 and 3, a light emitting device 200 according to an embodiment includes a substrate 210, light emitting structures 230 and 240, a first electrode 235, a current confining layer 270, A second conductive layer 280, a transparent conductive layer 260 (TCL), and a second electrode 290.

The transparent conductive layer 260 may include an opening 261. The second electrode 290 may be in contact with the conductive layer 290 through the opening 261.

The width W1 of the current confining layer 270 and the conductive layer 280 may be larger than the width W2 of the second electrode. When the width W1 of the current confinement layer 270 and the conductive layer 280 is equal to the width W2 of the second electrode, the operating voltage decreases but the light efficiency decreases accordingly. The width W1 of the current confinement layer 270 and the conductive layer 280 may be greater than the width W1 of the second electrode 290 in order to lower the operating voltage while maintaining the light efficiency.

In addition, the vertical extension line of the conductive layer 280 and the side surface of the second electrode 290 may have a predetermined distance d1. The distance d1 between the vertical extension of the conductive layer 280 and the side surface of the second electrode 290 may be 2 to 4 占 퐉.

4 is a graph according to an experimental value referred to for explaining the operating voltage and light efficiency according to the length d1.

4, the abscissa of the graph is the distance d1 between the vertical extension of the conductive layer 280 and the side of the second electrode 290. The left vertical axis of the graph is the light efficiency and the right vertical axis is the operating voltage.

As in the graph shown in Fig. 4, as dl increases, the light efficiency increases and decreases, and the operating voltage decreases. When d1 is in the range of 2 to 4 mu m, as in the case of the area indicated by reference numeral 410, the light efficiency can be maximized. That is, when d1 is smaller than 2 mu m, the operating voltage is not high, but the light efficiency is low. When d1 is larger than 4 mu m, the operating voltage is high and the light efficiency is low.

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

Referring to FIG. 5, a light emitting device package 300 according to an embodiment includes a body 310 having a cavity, a first electrode 330 and a second electrode 340 mounted on the body 310, A light source 320 which is electrically connected to the two electrodes 330 and 340 and an encapsulant 350 which is filled in the cavity to cover the light source 320.

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

The inner surface of the body 310 may be formed with an inclined surface. The reflection angle of the light emitted from the light source 320 can be changed according to the angle of the inclined surface, and thus the directivity angle of the light emitted to the outside can be adjusted.

Concentration of light emitted to the outside from the light source unit 320 increases as the directivity angle of light decreases. Conversely, as the directivity angle of light increases, the concentration of light emitted from the light source unit 320 decreases.

The shape of the cavity formed in the body 310 may be circular, square, polygonal, elliptical, or the like, and may have a curved shape, but the present invention is not limited thereto.

The light source unit 320 may be disposed in a cavity 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. The light emitting device may be a UV (Ultra Violet) light emitting device that emits ultraviolet rays, but the present invention is not limited thereto. In addition, one or more light emitting elements can be mounted.

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

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

5 illustrates that both the first electrode 330 and the second electrode 340 are bonded to the light source 320 by the wire 360. However, the present invention is not limited thereto. Particularly, in the case of the vertical light emitting device, Any one of the electrode 330 and the second electrode 340 may be bonded to the light source 320 by the wire 360 and may be electrically connected to the light source 320 without the wire 360 by the flip- have. Accordingly, when power is supplied to the first and second electrodes 330 and 340, power may be applied to the light emitting device 530. Meanwhile, a plurality of lead frames (not shown) may be mounted in the body 310 and each lead frame (not shown) may be electrically connected to the light emitting element 530, but is not limited thereto.

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

An encapsulant (not shown) may be filled in the cavity to cover the light source 320.

The encapsulant (not shown) may be formed of silicon, epoxy, or other resin material. The encapsulant may be filled in the cavity, and then the encapsulant may be ultraviolet or thermally cured.

The encapsulant (not shown) may include a fluorescent material, and the fluorescent material may be selected to be a wavelength of light emitted from the light source unit 320 so that the light emitting device package 300 may emit white light.

The phosphor may be one of a blue light emitting phosphor, a blue light emitting phosphor, a green light emitting phosphor, a yellow 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 depending on the wavelength of light emitted from the light source 320 Can be applied.

That is, the phosphor 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 portion 530 is a UV light emitting diode and the phosphor is a phosphor formed of a multilayer of red, green, and blue, the light in the ultraviolet region generated in the UV light emitting diode is excited while passing through the red, green, and blue phosphors, It can provide light.

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

The light emitting device according to the embodiment can be applied to an illumination system. The lighting system includes a structure in which a plurality of light emitting elements are arrayed and includes a display device shown in Figs. 6 and 7, a lighting device shown in Fig. 8, and may include a lighting lamp, a traffic light, a vehicle headlight, have.

6 is an exploded perspective view of a display device including a light emitting device according to an embodiment.

6, a display device 1000 according to an exemplary embodiment of the present invention includes a light guide plate 1041, a light source module 1031 for providing light to the light guide plate 1041, and a reflection member 1022 An optical sheet 1051 on the light guide plate 1041 and a display panel 1061 on the optical sheet 1051 and the light guide plate 1041 and the light source module 1031 and the reflection member 1022 But is not limited to, a bottom cover 1011.

The bottom cover 1011, the reflective sheet 1022, the light guide plate 1041, and the optical sheet 1051 can be defined as a light unit 1050.

The light guide plate 1041 serves to diffuse light into a surface light source. The light guide plate 1041 may be made of a transparent material, for example, acrylic resin such as polymethylmethacrylate (PET), polyethylene terephthalate (PET), polycarbonate (PC), cycloolefin copolymer (COC), and polyethylene naphtha late Resin. ≪ / RTI >

The light source module 1031 provides light to at least one side of the light guide plate 1041, and ultimately acts as a light source of the display device.

The light source module 1031 includes at least one light source module 1031 and may directly or indirectly provide light from one side of the light guide plate 1041. The light source module 1031 includes a substrate 1033 and a light emitting device 1035 according to the embodiment described above and the light emitting devices 1035 may be arrayed at a predetermined interval on the substrate 1033 .

The substrate 1033 may be a printed circuit board (PCB) including a circuit pattern (not shown). However, the substrate 1033 may include not only a general PCB, but also a metal core PCB (MCPCB), a flexible PCB (FPCB), and the like. When the light emitting element 1035 is mounted on the side surface of the bottom cover 1011 or on the heat radiation plate, the substrate 1033 can be removed. Here, a part of the heat radiating plate may be in contact with the upper surface of the bottom cover 1011.

The plurality of light emitting devices 1035 may be mounted on the substrate 1033 such that the light emitting surface is spaced apart from the light guiding plate 1041 by a predetermined distance. However, the present invention is not limited thereto. The light emitting device 1035 may directly or indirectly provide light to the light-incident portion, which is one surface of the light guide plate 1041, but the present invention is not limited thereto.

The reflective member 1022 may be disposed under the light guide plate 1041. The reflection member 1022 reflects the light incident on the lower surface of the light guide plate 1041 so as to face upward, thereby improving the brightness of the light unit 1050. The reflective member 1022 may be formed of, for example, PET, PC, or PVC resin, but is not limited thereto. The reflective member 1022 may be an upper surface of the bottom cover 1011, but is not limited thereto.

The bottom cover 1011 may house the light guide plate 1041, the light source module 1031, the reflective member 1022, and the like. To this end, the bottom cover 1011 may be provided with a housing portion 1012 having a box-like shape with an opened upper surface, but the present invention is not limited thereto. The bottom cover 1011 may be coupled to the top cover, but is not limited thereto.

The bottom cover 1011 may be formed of a metal material or a resin material, and may be manufactured using a process such as press molding or extrusion molding. In addition, the bottom cover 1011 may include a metal or a non-metal material having good thermal conductivity, but the present invention is not limited thereto.

The display panel 1061 is, for example, an LCD panel, including first and second transparent substrates facing each other, and a liquid crystal layer interposed between the first and second substrates. A polarizing plate may be attached to at least one surface of the display panel 1061, but the present invention is not limited thereto. The display panel 1061 displays information by light passing through the optical sheet 1051. Such a display device 1000 can be applied to various types of portable terminals, monitors of notebook computers, monitors of laptop computers, televisions, and the like.

The optical sheet 1051 is disposed between the display panel 1061 and the light guide plate 1041 and includes at least one light-transmitting sheet. The optical sheet 1051 may include at least one of a sheet such as a diffusion sheet, a horizontal and vertical prism sheet, and a brightness enhancement sheet. The diffusion sheet diffuses incident light, and the horizontal and / or vertical prism sheet condenses incident light into a display area. The brightness enhancing sheet improves the brightness by reusing the lost light. A protective sheet may be disposed on the display panel 1061, but the present invention is not limited thereto.

Here, the optical path of the light source module 1031 may include the light guide plate 1041 and the optical sheet 1051 as an optical member, but the invention is not limited thereto.

7 is a cross-sectional view illustrating a display device including a light emitting device according to an embodiment.

7, the display device 1100 includes a bottom cover 1152, a substrate 1120 on which the above-described light emitting device 1124 is arrayed, an optical member 1154, and a display panel 1155.

The substrate 1120 and the light emitting device 1124 may be defined as a light source module 1160. The bottom cover 1152, the at least one light source module 1160, and the optical member 1154 may be defined as a light unit 1150. The bottom cover 1152 may include a receiving portion 1153, but the present invention is not limited thereto. The light source module 1160 includes a substrate 1120 and a plurality of light emitting devices 1124 arranged on the substrate 1120.

Here, the optical member 1154 may include at least one of a lens, a light guide plate, a diffusion sheet, a horizontal and vertical prism sheet, and a brightness enhancement sheet. The light guide plate may be made of a PC material or a polymethyl methacrylate (PMMA) material, and the light guide plate may be removed. The diffusion sheet diffuses incident light, and the horizontal and vertical prism sheets condense incident light into a display area. The brightness enhancing sheet enhances brightness by reusing the lost light.

The optical member 1154 is disposed on the light source module 1160 and performs surface light source, diffusion, and light condensation of light emitted from the light source module 1160.

8 is an exploded perspective view of a lighting device including a light emitting device according to an embodiment.

8, the lighting apparatus according to the embodiment includes a cover 2100, a light source module 2200, a heat discharger 2400, a power supply unit 2600, an inner case 2700, and a socket 2800 . Further, the illumination device according to the embodiment may further include at least one of the member 2300 and the holder 2500. The light source module 2200 may include a light emitting device according to an embodiment of the present invention.

For example, the cover 2100 may have a shape of a bulb or a hemisphere, and may be provided in a shape in which the hollow is hollow and a part is opened. The cover 2100 may be optically coupled to the light source module 2200. For example, the cover 2100 may diffuse, scatter, or excite light provided from the light source module 2200. The cover 2100 may be a kind of optical member. The cover 2100 may be coupled to the heat discharging body 2400. The cover 2100 may have an engaging portion that engages with the heat discharging body 2400.

The inner surface of the cover 2100 may be coated with a milky white paint. Milky white paints may contain a diffusing agent to diffuse light. The surface roughness of the inner surface of the cover 2100 may be larger than the surface roughness of the outer surface of the cover 2100. This is for sufficiently diffusing and diffusing the light from the light source module 2200 and emitting it to the outside.

The cover 2100 may be made of glass, plastic, polypropylene (PP), polyethylene (PE), polycarbonate (PC), or the like. Here, polycarbonate is excellent in light resistance, heat resistance and strength. The cover 2100 may be transparent so that the light source module 2200 is visible from the outside, and may be opaque. The cover 2100 may be formed by blow molding.

The light source module 2200 may be disposed on one side of the heat discharging body 2400. Accordingly, heat from the light source module 2200 is conducted to the heat discharger 2400. The light source module 2200 may include a light emitting device 2210, a connection plate 2230, and a connector 2250.

The member 2300 is disposed on the upper surface of the heat discharging body 2400 and has guide grooves 2310 into which the plurality of light emitting elements 2210 and the connector 2250 are inserted. The guide groove 2310 corresponds to the substrate of the light emitting device 2210 and the connector 2250.

The surface of the member 2300 may be coated or coated with a light reflecting material. For example, the surface of the member 2300 may be coated or coated with a white paint. The member 2300 reflects the light reflected by the inner surface of the cover 2100 toward the cover 2100 in the direction toward the light source module 2200. Therefore, the light efficiency of the illumination device according to the embodiment can be improved.

The member 2300 may be made of an insulating material, for example. The connection plate 2230 of the light source module 2200 may include an electrically conductive material. Therefore, electrical contact can be made between the heat discharging body 2400 and the connecting plate 2230. The member 2300 may be formed of an insulating material to prevent an electrical short circuit between the connection plate 2230 and the heat discharging body 2400. The heat discharger 2400 receives heat from the light source module 2200 and heat from the power supply unit 2600 to dissipate heat.

The holder 2500 blocks the receiving groove 2719 of the insulating portion 2710 of the inner case 2700. Therefore, the power supply unit 2600 housed in the insulating portion 2710 of the inner case 2700 is sealed. The holder 2500 has a guide protrusion 2510. The guide protrusion 2510 may have a hole through which the protrusion 2610 of the power supply unit 2600 passes.

The power supply unit 2600 processes or converts an electrical signal provided from the outside and provides the electrical signal to the light source module 2200. The power supply unit 2600 is housed in the receiving groove 2719 of the inner case 2700 and is sealed inside the inner case 2700 by the holder 2500.

The power supply unit 2600 may include a protrusion 2610, a guide unit 2630, a base 2650, and a protrusion 2670.

The guide portion 2630 has a shape protruding outward from one side of the base 2650. The guide portion 2630 may be inserted into the holder 2500. A plurality of components may be disposed on one side of the base 2650. The plurality of components include, for example, a DC converter for converting AC power supplied from an external power source into DC power, a driving chip for controlling driving of the light source module 2200, an ESD (ElectroStatic discharge) protective device, and the like, but the present invention is not limited thereto.

The protrusion 2670 has a shape protruding outward from the other side of the base 2650. The protrusion 2670 is inserted into the connection portion 2750 of the inner case 2700 and receives an external electrical signal. For example, the protrusion 2670 may be equal to or smaller than the width of the connection portion 2750 of the inner case 2700. One end of each of the positive wire and the negative wire is electrically connected to the protrusion 2670 and the other end of the positive wire and the negative wire are electrically connected to the socket 2800.

The inner case 2700 may include a molding part together with the power supply part 2600. The molding part is a hardened portion of the molding liquid so that the power supply unit 2600 can be fixed inside the inner case 2700.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of illustration, It can be seen that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (8)

Board;
A light emitting structure formed on the substrate, the light emitting structure including a first semiconductor layer, a second semiconductor layer, and an active layer between the first semiconductor layer and the second semiconductor layer;
A current confinement layer formed in a partial region on the second semiconductor layer;
A conductive layer formed on the current confining layer;
A second electrode formed on the conductive layer, the second electrode overlapping at least a part of the current confined layer and the conductive layer in a vertical direction; And
And a transparent conductive layer which is located on the light emitting structure and in which at least a part of the current confining layer and the conductive layer overlap with each other in a vertical direction. The method according to claim 1,
Wherein the current confinement layer and the conductive layer have a width greater than a width of the second electrode. 3. The method of claim 2,
And a distance (d1) between a vertical extension line of the conductive layer and a side surface of the second electrode is 2 占 퐉 or more and 4 占 퐉 or less. The method according to claim 1,
Wherein the current confined layer is a DBR (Distributed Bragg Reflector) layer. The method according to claim 1,
Wherein the conductive layer is aluminum (Al), silver (Ag), or rhodium (Rh). The method according to claim 1,
Wherein the transparent conductive layer comprises an opening. The method according to claim 6,
And the second electrode and the conductive layer are in contact with each other. The method according to claim 1,
Wherein a width of the current confining layer is 9 占 퐉 or more and 12 占 퐉 or less.

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