KR20130140417A - Light emitting device and method for fabricating the same - Google Patents

Abstract

A light emitting device according to the embodiment includes: a semiconductor layer; an electrode finger part which is arranged on the semiconductor layer and forms an ohmic contact with the semiconductor layer; an ohmic part which is arranged on the semiconductor layer, is separated from the electrode finger part, and forms the ohmic contact with the semiconductor layer; and a pad part which is arranged on the electrode finger part and the ohmic part.

Description

TECHNICAL FIELD The present invention relates to a light emitting device,

The embodiment relates to a light emitting device and a method of manufacturing the same.

LED (Light Emitting Diode) is a device that converts electrical signals into infrared, visible light or light using the characteristics of compound semiconductors. It is used in household appliances, remote controls, display boards, The use area of LED is becoming wider. LED has advantages of low power consumption, semi-permanent lifetime, fast response speed, safety, and environmental friendliness compared to conventional light sources such as fluorescent lamps and incandescent lamps.

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.

LED semiconductors are grown by a process such as MOCVD or molecular beam epitaxy (MBE) on a substrate such as sapphire or silicon carbide (SiC) having a hexagonal system structure.

In the case of LED, the flow of current is highly related to the efficiency of the light emitting device. The ohmic contact layer among the components of the LED particularly affects the diffusion of the current of the light emitting device.

1 is a plan view illustrating a phenomenon in which a conventional etchant penetrates and corrodes. Referring to Figure 1 it can be seen that the pad portion may be corroded due to the penetration of the etchant. When the pad part is corroded by the penetration of the etchant, the pad part may be peeled off.

The embodiment provides a light emitting device having an improved pad peeling phenomenon due to an etchant and a method of manufacturing the light emitting device.

The light emitting device according to the present embodiment includes a semiconductor layer; An electrode finger disposed on the semiconductor layer and making ohmic contact with the semiconductor layer; An ohmic part disposed on the semiconductor layer and spaced apart from the electrode finger part and making an ohmic contact with the semiconductor layer; It may include a pad portion disposed on the electrode finger portion and the ohmic portion.

Method of manufacturing a light emitting device according to the present embodiment comprises the steps of forming a semiconductor layer; Disposing an electrode finger disposed on the semiconductor layer and making ohmic contact with the semiconductor layer; Disposing an ohmic part disposed on the semiconductor layer and spaced apart from the electrode finger part and making an ohmic contact with the semiconductor layer; And disposing a pad part on the electrode finger part and the ohmic part.

The light emitting device according to the embodiment can effectively prevent the penetration of the etchant can improve the phenomenon that the pad can be peeled off.

According to another embodiment, a light emitting device having an improved phenomenon that a pad may be peeled off may be manufactured.

1 is a plan view illustrating a phenomenon in which a conventional etchant penetrates and a pad part is corroded.
2A is a cross-sectional view showing the structure of a light emitting device according to the embodiment.
2B is a cross-sectional view showing the structure of a light emitting device according to the embodiment.
3A is a plan view showing the structure of a light emitting device according to the embodiment.
3B is a plan view illustrating the structure of a light emitting device according to the embodiment.
3C is a plan view illustrating a structure of a light emitting device according to the embodiment.
3D is a plan view illustrating a structure of a light emitting device according to the embodiment.
3E is a plan view showing the structure of a light emitting device according to the embodiment.
4A is a cross-sectional view illustrating a structure of a light emitting device according to the embodiment.
4B is a cross-sectional view illustrating a structure of a light emitting device according to the embodiment.
4C is a cross-sectional view illustrating a structure of the light emitting device according to the exemplary embodiment of FIG. 3A, taken along the AA ′ direction.
5A is a perspective view illustrating a light emitting device package including the light emitting device of the embodiment.
5B is a cross-sectional view illustrating a light emitting device package including the light emitting device of the embodiment.
6A is a perspective view illustrating a lighting device including a light emitting device module according to an embodiment.
6B is a cross-sectional view illustrating a lighting device including a light emitting device module according to an embodiment.
7 is an exploded perspective view illustrating a backlight unit including a light emitting device module according to an embodiment.
8 is an exploded perspective view illustrating a backlight unit including a light emitting device module according to an embodiment.

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

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

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

Unless otherwise defined, all terms (including technical and scientific terms) used in the present specification may be used in a sense that can be commonly understood by those skilled in the art. Also, commonly used predefined terms are not ideally or excessively interpreted unless explicitly defined otherwise.

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

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

Hereinafter, embodiments will be described in detail with reference to the drawings. 2A is a cross-sectional view illustrating a structure of a light emitting device 1000 according to an exemplary embodiment of the present invention. Referring to FIG. 2A, the light emitting device 1000 according to the embodiment may include an omnidirectional reflector layer 20 and an ODR layer disposed on the substrate 10 and reflecting light incident at any angle. 20 is disposed on the p-omic layer 30 and the p-omic layer 30 to make ohmic contact with the electrode, and the wavelength larger than a specific value according to the bandgap energy. The light emitting structure layer 50 including the transparent conductive layer 40 that transmits without being absorbed, the first semiconductor layer 52, the active layer 54, and the second semiconductor layer 56 disposed on the transparent conductive layer 40. ), An electrode finger part 70 disposed on the second semiconductor layer 56, and a pad part 100 disposed on the electrode finger part 70.

The substrate 10 may be formed of a semiconductor material according to an embodiment, and may be formed of, for example, silicon, germanium, gallium arsenide, zinc oxide, silicon carbide, It can be implemented with a carrier wafer such as a silicon germanium (SiGe), gallium nitride (GaN), gallium (ⅲ) oxide (Ga ₂ O _3).

The substrate 10 may be formed of a conductive material. According to the embodiment, the metal may be formed of, for example, gold (Au), nickel (Ni), tungsten (W), molybdenum (Mo), copper (Cu), aluminum (Al), tantalum (Ta), or silver. It may be formed of any one selected from (Ag), platinum (Pt), chromium (Cr) or formed of two or more alloys, and may be formed by stacking two or more of the above materials. When the substrate 10 is formed of a metal, the heat generated in the light emitting device 1000 can be easily released, thereby improving the thermal stability of the light emitting device.

The substrate 10 may have a PSS (Patterned Substrate) structure on its top surface in order to enhance light extraction efficiency, but the present invention is not limited thereto. The substrate 10 facilitates the release of heat generated in the light emitting device 1000, thereby improving the thermal stability of the light emitting device 1000.

The substrate 10 may be disposed under the ODR layer 20, but is not limited thereto. The substrate 10 may be disposed above the first electrode 90 in the case of a vertical LED.

In the ODR layer 20, silver (Ag) is mainly used for reflecting light, but it is not limited thereto. The ODR layer 20 may be formed of a metal having a high reflectivity. The ODR layer 20 can reflect any incoming light at any angle. The ODR layer 20 may be structurally patterned or a transparent layer may be inserted into the interlayer film to further enhance the reflectivity of this layer. The ODR layer 20 can improve the reflectance according to the incident angle by inserting indium tin oxide (ITO) on silver (Ag).

The ODR layer 20 may be disposed on top of the substrate 10, but is not limited thereto. The ODR layer 20 may be disposed under the p-ohmic layer 30, but is not limited thereto.

The p-ohmic layer 30 may be formed by laminating a single metal, a metal alloy, a metal oxide, or the like so as to efficiently inject holes. For example, the p-ohmic layer 30 may be formed of ITO, IZO (In-ZnO), GZO (Ga-ZnO), AZO (Al- ZnO), IGZO ITO, Ni / IrOx / Au, and Ni / IrOx / Au / ITO, Ni, and Ag.

The p-ohmic layer 30 is intended to make ohmic contact with the second semiconductor layer 56 well. The P-ohmic layer 30 may be disposed under the second semiconductor layer 56, but is not limited thereto.

The transparent conductive layer 40 serves as a conductive layer. The transparent conductive layer 40 may be made of a material such as GaP, but is not limited thereto.

The transparent conductive layer 40 can pass therethrough without absorption in the case of a wavelength larger than the wavelength corresponding to the band gap energy. For example, when the band gap energy is 2.24 eV, the transparent conductive layer 40 can transmit a wavelength of 553 nm or more without absorbing it.

The transparent conductive layer 40 may be disposed on the p-ohmic layer 30, but is not limited thereto. The transparent conductive layer 40 may be disposed under the light emitting structure layer 50, but is not limited thereto.

The light emitting structure layer 50 includes a first semiconductor layer 52, an active layer 54, and a second semiconductor layer 56.

The first semiconductor layer 52 may be disposed on the substrate 10. The first semiconductor layer 52 may be disposed on a buffer layer (not shown) to match the lattice constant difference with the substrate 10, but is not limited thereto. Although the first semiconductor layer 52 can be grown on the substrate 10, the first semiconductor layer 52 is not limited to the horizontal type light emitting device and can be applied to the vertical type light emitting device.

The first semiconductor layer 52 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 -x- y} N (0 ≦ x ≦ 1, 0 ≦ _y ≦ 1, A semiconductor material having a composition formula of 0 ≦ x + y ≦ 1, for example, gallium nitride (GaN), aluminum nitride (AlN), aluminum gallium nitride (AlGaN), indium gallium nitride (InGaN), indium nitride (InN), InAlGaN, AlInN and the like can be selected. The first semiconductor layer 52 may be doped with an n-type dopant such as, for example, silicon (Si), germanium (Ge), tin (Sn), selenium (Se) or tellurium (Te).

The active layer 54 may be disposed on the first semiconductor layer 52. The active layer 54 may be disposed between the second semiconductor layer 56 and the first semiconductor layer 52.

The active layer 54 may be formed of a semiconductor material. The active layer 54 may be formed of a single or multi-well structure or the like using a compound semiconductor material of Group 3-V group elements. The active layer 54 may be formed of a nitride semiconductor. For example, the active layer 54 may include gallium nitride (GaN), indium gallium nitride (InGaN), and indium gallium nitride (InAlGaN).

The second semiconductor layer 56 may be disposed on the active layer 54. The second semiconductor layer 56 may be formed of a p-type semiconductor layer doped with a p-type dopant. The second semiconductor layer 56 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 ( Gallium nitride), aluminum nitride (AlN), aluminum gallium nitride (AlGaN), indium gallium nitride (InGaN), indium nitride (InN), InAlGaN, AlInN, etc., and magnesium (Mg), zinc (Zn) P-type dopants such as Ca), strontium (Sr), and barium (Ba) may be doped.

The first semiconductor layer 52, the active layer 54 and the second semiconductor layer 56 may be formed by a method such as metal organic chemical vapor deposition (MOCVD), chemical vapor deposition (CVD) May be formed using a method such as plasma enhanced chemical vapor deposition (PECVD), molecular beam epitaxy (MBE), or hydride vapor phase epitaxy (HVPE) The present invention is not limited thereto.

The doping concentration of the conductive dopant in the first semiconductor layer 52 and the second semiconductor layer 56 may be uniform or non-uniform, but is not limited thereto.

The reflective layer (not shown) may be formed of a metal layer containing Al, Ag, or an alloy containing Al or Ag. The reflective layer (not shown) may be formed of aluminum or silver, and may effectively reflect the light generated in the active layer 54.

The reflective layer (not shown) may be disposed on the light emitting structure layer 50, but is not limited thereto. The reflective layer (not shown) may be disposed under the electrode fingers 70, but is not limited thereto.

The electrode fingers 70 may be formed by laminating a single metal, a metal alloy, a metal oxide, or the like so as to efficiently perform hole injection. For example, the electrode fingers 70 may be formed of ITO, IZO (In-ZnO), GZO (Ga-ZnO), AZO (Al-ZnO), IGZO (In- Ni / IrOx / Au, and at least one of Ni / IrOx / Au / ITO, Ni, and Ag. The electrode fingers 70 may be formed of GaAs. The electrode finger 70 may make an ohmic contact with the second semiconductor layer 56. The electrode fingers 70 can make an ohmic contact with the second semiconductor layer 56 to reduce the resistance and allow the current to flow well.

The electrode fingers 70 may be disposed on the reflective layer (not shown), but are not limited thereto. The electrode fingers 70 may be disposed under the pad unit 100, but are not limited thereto.

 The ohmic portion 200 may arrange the pad portion 100 on the ohmic portion 200 and the electrode finger 70 after the electrode finger 70 is disposed. The ohmic portion 200 may be disposed to prevent the chunks from penetrating under the pad portion 100 during texturing for increasing the light efficiency. The ohmic part 200 may be formed of the same material as the electrode finger part 70 and may be made of GaAs. The ohmic portion 200 may be formed of a material having a relatively lower etchant etch rate than the second semiconductor layer 56. The ohmic portion 200 can effectively prevent the pad portion 100 from being corroded when the lower semiconductor layer is corroded. When the material of the ohmic portion 200 is diffused into the lower semiconductor layer, the corrosion rate may be further lowered.

The ohmic portion 200 should make an ohmic contact with the semiconductor layer like the electrode finger 70. The ohmic portion 200 may be formed of a material that makes an ohmic contact with the second semiconductor layer 56. When the ohmic portion 200 makes an ohmic contact with the second semiconductor layer 56, the resistance can be reduced and the current can flow well. The ohmic portion 200 and the electrode fingers 70 should be doped with N-type when forming n-ohmic and P-type when forming with p-ohmic. In the case where the electrode finger 70 and the ohmic portion 200 are made of a group III-V compound, the Group I element may be doped when the Group VI element forms P-Ohmic when forming N- have. When the Group 4 element is doped, the electrode finger 70 and the ohmic portion 200 may form N-Ohmic or P-Ohmic in accordance with a substituent among the Group 3-5 compounds.

2B is a cross-sectional view illustrating the structure of the light emitting structure layer 50, the electrode finger unit 70, and the ohmic unit 200. The light emitting structure layer 50 and the electrode finger part 70 form an ohmic contact. The light emitting structure layer 50 and the ohmic part 200 form an ohmic contact. The light emitting structure layer 50 and the electrode finger 70 may make ohmic contact to reduce resistance, and may allow current to flow well between the foot structure layer 50 and the electrode finger 70. Similarly, the light emitting structure layer 50 and the ohmic unit 200 may also make ohmic contacts to allow current to flow well.

3A to 3E are plan views illustrating embodiments of the present invention. Referring to FIG. 3A, the electrode finger 70 and the ohmic part 200 may be one or more, and the number of the electrode finger 70 and the ohmic part 200 is not limited to the drawing. The pad part 100 is disposed above the electrode finger part 70 and the ohmic part 200, but the pad part 100 is not shown in FIG. 3A. In the ohmic part 200, when the pad part 100 is disposed above, the ohmic part 200 may be disposed under the pad part 100. In the electrode finger part 70, when the pad part 100 is disposed above, a part of the electrode finger part 70 may be disposed under the pad part 100.

Referring to FIG. 3A, the ohmic part 200 is illustrated in the shape of a donut, but is not limited thereto. The ohmic part 200 may be formed not only in the shape of a donut but also in the shape of a disc. The efficiency of the ohmic unit 200 is increased as the width is as thin as possible, and may be formed to have a thickness of 3 μm to 7 μm. In the ohmic part 200, it is difficult to form a thin width of 3 μm or less in a process, and when the width is formed to be 7 μm or more, efficiency may be greatly reduced.

The ohmic unit 200 may have the same width as the electrode finger unit 70 but is not limited thereto. When the ohmic portion 200 has the same width as the electrode finger portion 70, the ohmic portion 200 may be processed at a time in a process so that the ohmic portion 200 and the electrode finger portion 70 may be easily formed.

If the ohmic part 200 has a large distance from the electrode finger part 70, the etchant may penetrate therebetween, and thus it may be difficult to obtain an effect of improving the pad peeling phenomenon according to the present embodiment. As the ohmic part 200 is disposed closer to the electrode finger part 70, the penetration of the etchant may be effectively prevented, and the distance between the ohmic part 200 and the electrode finger part 70 may be 1 μm to 5 μm. have. The ohmic part 200 is hard to be disposed below 1 μm due to a process difficulty, and when the ohmic part 200 is larger than 5 μm, it is difficult to obtain an improvement effect.

3B to 3E illustrate a shape that may be formed by the ohmic part 200, but are not limited to the exemplary embodiment of the present invention and may include all possible patterns. The ohmic unit 200 is smaller than the pad unit 100 and is formed as large as possible, which is most effective in increasing efficiency by spreading current.

4A is a cross-sectional view of FIG. 3A and FIG. 4B is a cross-sectional view taken along the line A-A 'of FIG. 3A. The pad part 100 is not shown in FIG. 3A.

In another embodiment of the present invention will be described a method of manufacturing a light emitting device.

The light emitting device according to the present exemplary embodiment may include forming a semiconductor layer and disposing an electrode finger part 70 and an ohmic part 200 so as not to stick to each other on the semiconductor layer. When the ohmic portion 200 is disposed so as to be attached to all of the electrode finger portions 70, current hardly flows. The ohmic unit 200 may be disposed to be spaced apart from the electrode finger unit 70.

The pad part 100 may be disposed on the electrode finger part 70 and the ohmic part 200. The pad part 100 must be partially in contact with the electrode finger part 70. The pad unit 100 may be disposed such that all of the ohmic unit 200 is under the pad unit 100. The pad part 100 may be corroded by an etchant when texturing the lower semiconductor layer using an etchant to increase light efficiency. The pad part 100 may effectively prevent the penetration of the etchant by the electrode finger part 70 and the ohmic part 200, so that corrosion may not occur. Referring to FIG. 4C, an etching may be performed by covering the protective layer 250 to prevent corrosion of the pad part 100 during etching.

When the ohmic part 200 is formed of the same material as the electrode finger part 70, the electrode finger part 70 and the ohmic part 200 may be formed at a time in a process, which may be advantageous in terms of cost. It is not limited to this.

5A is a perspective view illustrating a light emitting device package 300 according to an exemplary embodiment of the present invention, and FIG. 5B is a cross-sectional view illustrating a light emitting device package 300 according to another exemplary embodiment.

5A and 5B, the light emitting device package 300 according to the embodiment includes a body 310 having a cavity, first and second electrodes 340 and 350 mounted on the body 310, A light emitting device 320 electrically connected to the two electrodes, and an encapsulant 330 formed in the cavity. The encapsulant 330 may include a phosphor (not shown).

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 ), new geo-isotactic polystyrene (SPS), metal materials, sapphire (Al ₂ O _3), beryllium oxide (BeO), is a printed circuit board (PCB, printed circuit board), it may be formed of at least one of ceramic. 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 emitting device 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.

The shape of the cavity formed in the body 310 as viewed from above may be circular, rectangular, polygonal, elliptical, or the like, and in particular, may have a curved shape, but is not limited thereto.

The encapsulant 330 may be filled in the cavity and may include a phosphor (not shown). The encapsulant 330 may be formed of transparent silicone, epoxy, and other resin materials. The encapsulant 330 may be formed in such a manner that the encapsulant 330 is filled in the cavity and then cured by ultraviolet rays or heat.

The phosphor (not shown) may be selected according to the wavelength of the light emitted from the light emitting device 320 to allow the light emitting device package 300 to realize white light.

The fluorescent material (not shown) included in the encapsulant 330 may be a blue light emitting phosphor, a blue light emitting fluorescent material, a green light emitting fluorescent material, a yellow green light emitting fluorescent material, a yellow light emitting fluorescent material, Fluorescent material, orange light-emitting fluorescent material, and red light-emitting fluorescent material may be applied.

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

When the light emitting device 320 is a green light emitting diode, a magenta fluorescent material or a blue and red fluorescent material (not shown) are mixed. When the light emitting device 320 is a red light emitting diode, For example, a mixture of blue and green phosphors.

The phosphor (not shown) may be a known one such as YAG, TAG, sulfide, silicate, aluminate, nitride, carbide, nitridosilicate, borate, fluoride, or phosphate.

The first electrode 340 and the second electrode 350 may be mounted on the body 310. The first electrode 340 and the second electrode 350 may be electrically connected to the light emitting device 320 to supply power to the light emitting device 320.

The first electrode 340 and the second electrode 350 are electrically separated from each other and reflect light generated from the light emitting device 320 to increase light efficiency. The first electrode 340 and the second electrode 350 may discharge heat generated from the light emitting device 320 to the outside.

The light emitting device 320 is mounted on the first electrode 340 but the present invention is not limited thereto and the light emitting device 320 and the first electrode 340 and the second electrode 350 may be wire bonded ) Method, a flip chip method, or a die bonding method.

The first electrode 340 and the second electrode 350 may be formed of a metal material such as titanium (Ti), copper (Cu), nickel (Ni), gold (Au), chromium (Cr), tantalum ), Platinum (Pt), tin (Sn), silver (Ag), phosphorous (P), aluminum (Al), indium (In), palladium (Pd), cobalt ), Hafnium (Hf), ruthenium (Ru), and iron (Fe). The first electrode 340 and the second electrode 350 may have a single-layer structure or a multi-layer structure, but the present invention is not limited thereto.

The light emitting device 320 is mounted on the first electrode 340 and may be a light emitting device that emits light such as red, green, blue, or white, or a UV (Ultra Violet) However, the present invention is not limited thereto. One or more light emitting devices 320 may be mounted.

The light emitting device 320 is applicable to both a horizontal type whose electrical terminals are all formed on the upper surface, a vertical type formed on the upper and lower surfaces, or a flip chip.

The light emitting device package 300 may include a light emitting device.

The light emitting device 320 may include a first active layer (not shown), a second active layer (not shown), and a carrier injection layer (not shown). The light emitting device 320 includes a carrier injection layer (not shown) to accelerate the mobility of holes provided in a second semiconductor layer (not shown) to provide a first active layer (not shown) and a second active layer (not shown) can do.

The reliability of the light emitting device package 300 including the light emitting device 320 including the carrier injection layer (not shown) and the light extraction amount can be maximized.

A light guide plate, a prism sheet, a diffusion sheet, and the like, which are optical members, may be disposed on a light path of the light emitting device package 300.

The light emitting device package 300, the substrate, and the optical member may function as a light unit. Another embodiment may be implemented as a display device, an indicating device, a lighting system including a light emitting device (not shown) or a light emitting device package 300, for example, the lighting system may include a lamp, a streetlight .

6A is a perspective view illustrating a lighting system 400 including a light emitting device according to an embodiment, and FIG. 6B is a cross-sectional view illustrating a cross-sectional view taken along line D-D ′ of the lighting system of FIG. 6A.

6B is a cross-sectional view of the illumination system 400 of FIG. 6A cut in the longitudinal direction Z and the height direction X and viewed in the horizontal direction Y. FIG.

6A and 6B, the lighting system 400 may include a body 410, a cover 430 coupled to the body 410, and a finishing cap 450 positioned at either end of the body 410 have.

The lower surface of the body 410 is fastened to the light emitting device module 443, the body 410 is conductive and so that the heat generated from the light emitting device package 444 can be discharged to the outside through the upper surface of the body 410 The heat dissipation effect may be formed of an excellent metal material, but is not limited thereto.

The light emitting device package 444 includes a light emitting device (not shown).

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

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

The cover 430 may protect the light emitting device module 443 from the foreign matters. The cover 430 may include diffusing particles to prevent glare of light generated from the light emitting device package 444 and to uniformly emit light to the outside, and may also include at least one of an inner surface and an outer surface of the cover 430. A prism pattern or the like may be formed on the surface. In addition, a phosphor may be applied to at least one of an inner surface and an outer surface of the cover 430.

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

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

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

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

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

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

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

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

The backlight unit 570 may convert the light provided from the light emitting device module 520, the light emitting device module 520 into a surface light source, and provide the light guide plate 530 to the liquid crystal display panel 510. Reflective sheet for reflecting the light emitted from the rear of the light guide plate 530 and the plurality of films 550, 560, 564 to uniform the luminance distribution of the light provided from the 530 and improve the vertical incidence ( 540.

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

The light extraction efficiency of the backlight unit 570 including the light emitting device package 524 can be improved and the reliability of the backlight unit 570 can be further improved.

The backlight unit 570 is a diffusion film 566 for diffusing light incident from the light guide plate 530 toward the liquid crystal display panel 510 and a prism film 550 for condensing the diffused light to improve vertical incidence. It may be configured, and may include a protective film 564 for protecting the prism film 550.

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

8 is a direct-view liquid crystal display device 600 according to the embodiment. The liquid crystal display 600 may include a liquid crystal display panel 610 and a backlight unit 670 for providing light to the liquid crystal display panel 610. Since the liquid crystal display panel 610 is the same as that described with reference to FIG. 7, a detailed description thereof will be omitted.

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

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

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

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

The configuration and the method of the embodiments described above are not limitedly applied, but the embodiments may be modified so that all or some of the embodiments are selectively combined so that various modifications can be made. .

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

10: substrate
20: ODR layer
30: p-ohmic layer
40: transparent conductive layer
50: light emitting structure layer
52: first semiconductor layer
54:
56: second semiconductor layer
70: electrode fingering
90: first electrode
100: pad portion
200: ohmic
250: protective layer

Claims (16)

A first semiconductor layer, an active layer, a second semiconductor layer; and
An electrode finger disposed on the second semiconductor layer and making ohmic contact with the second semiconductor layer;
An ohmic part disposed on the second semiconductor layer and spaced apart from the electrode finger part and making an ohmic contact with the second semiconductor layer;
A light emitting device comprising a pad portion disposed on the electrode finger portion and the concave portion. The method of claim 1,
Light emitting device comprising at least one electrode finger portion. The method of claim 1,
Light emitting device comprising at least one ohmic portion. The method of claim 1,
A light emitting device comprising a portion of the electrode finger portion disposed below the pad portion. The method of claim 1,
A light emitting device comprising all of the ohmic portion is disposed below the pad portion. The method of claim 1,
And the ohmic part is formed of a material whose reaction with an etchant is slower than the reaction of the second semiconductor layer. The method of claim 1,
The electrode finger unit comprises a light emitting device formed of a material doped with n-type or p-type. The method of claim 1,
And the ohmic part is formed of a material doped with an n-type or p-type. The method of claim 1,
The ohmic portion comprises a light emitting device formed of GaAs. The method of claim 1,
The electrode finger and the ohmic portion is formed of the same material. The method of claim 1,
The ohmic portion of the light emitting device comprising a smaller than the pad portion. The method of claim 1,
The ohmic portion of the light emitting device comprising a width of 3㎛ 7㎛. The method of claim 1,
Light emitting device comprising a disposed so that the distance between the ohmic portion and the electrode finger portion is 1㎛ to 5㎛. The method of claim 1,
The ohmic portion and the electrode finger portion comprises a light emitting device comprising the same width. Forming a first semiconductor layer, an active layer, and a second semiconductor layer;
Disposing an electrode finger portion disposed on the second semiconductor layer and making ohmic contact with the second semiconductor layer;
Forming an ohmic part disposed on the second semiconductor layer and spaced apart from the electrode finger part and making an ohmic contact with the second semiconductor layer;
Disposing a pad part on the electrode finger part and the ohmic part; And
A method of manufacturing a light emitting device, the method comprising: texturing the lower light emitting structure layer using an etchant. The method of claim 15,
And forming the electrode fingers and the ohmic parts from the same material.

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