Patent Publication Number: US-9899567-B2

Title: Light emitting device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a Continuation of copending U.S. application Ser. No. 14/179,420, filed on Feb. 12, 2014, which is a Continuation of U.S. application Ser. No. 12/943,628, filed on Nov. 10, 2010 (now U.S. Pat. No. 8,653,547, Issued on Feb. 18, 2014), which claims priority under 35 U.S.C. § 119(a) to Application No. 10-2010-0021289, filed in The Republic of Korea on Mar. 10, 2010, all of which are hereby expressly incorporated by reference into the present application. 
    
    
     BACKGROUND 
     Embodiments relate to a light emitting device and a light emitting device package. 
     A light emitting diode (LED) is a kind of a semiconductor device for converting electric energy into light. The LED has advantages such as low power consumption, a semi-permanent life cycle, a fast response time, safety, and environment friendly compared to the related art light source such as a fluorescent lamp and an incandescent bulb. Many studies are being in progress in order to replace the related art light source with an LED. Also, the LED is being increasingly used according to the trend as light sources of a lighting device such as a variety of lamps and streetlights, a lighting unit of a liquid crystal display device, and a scoreboard in indoor and outdoor places. 
     SUMMARY 
     Embodiments provide a light emitting device having a new structure and a light emitting device package. 
     Embodiments also provide a light emitting device having improved light emitting efficiency. 
     Embodiments also provide a light emitting device having improved light extraction efficiency. 
     Embodiments also provide a light emitting device, which emits uniform light. 
     In one embodiment, a light emitting device includes: a first electrode; a light emitting structure including a first semiconductor layer, an active layer, and a second semiconductor layer on the first electrode; a second electrode on the light emitting structure; and a reflective member on at least lateral surface of the second electrode. 
     In another embodiment, a light emitting device includes: a first electrode; an adhesive layer on the first electrode; a reflective layer on the adhesive layer; an ohmic contact layer on the reflective layer; a channel layer on the adhesive layer disposed on a lateral surface of the ohmic contact layer; a light emitting structure including a first semiconductor layer on the channel layer and the ohmic contact layer, an active layer on the first semiconductor layer, and a second semiconductor layer on the active layer; a second electrode on the light emitting structure, the second electrode having an inclined and uneven surface at least lateral surface thereof; a reflective member on the at least lateral surface of the second electrode, the reflective member having a shape corresponding to that of the lateral surface of the second electrode; and a passivation layer extending from a top surface of the channel layer to a lateral surface of the light emitting structure. 
     In further another embodiment, a light emitting device package includes: a body; at least one lead electrode on the body; and a light emitting device electrically connected to the lead electrode, wherein the light emitting device includes: a first electrode; a light emitting structure including a first semiconductor layer, an active layer, and a second semiconductor layer on the first electrode; a second electrode on the light emitting structure; and a reflective member on at least lateral surface of the second electrode. 
     The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features will be apparent from the description and drawings, and from the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side sectional view of a light emitting device according to a first embodiment. 
         FIG. 2  is a plan view illustrating the light emitting device of  FIG. 1 . 
         FIG. 3  is an enlarged view illustrating various formation structures of a second electrode and a reflective member in the light emitting device according to the first embodiment. 
         FIGS. 4 to 14  are views illustrating a process of manufacturing the light emitting device according to the first embodiment. 
         FIG. 15  is a side sectional view of a light emitting device according to a second embodiment. 
         FIG. 16  is a plan view illustrating the light emitting device of  FIG. 15 . 
         FIG. 17  is a side sectional view of a light emitting device according to a third embodiment. 
         FIG. 18  is a side sectional view of a light emitting device according to a fourth embodiment. 
         FIG. 19  is a sectional view of a light emitting device package including a light emitting device according to an embodiment. 
         FIG. 20  is an exploded perspective view of a display device according to am embodiment. 
         FIG. 21  is a view of a display device according to an embodiment. 
         FIG. 22  is a perspective view of a lighting device according to an embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     In the descriptions of embodiments, it will be understood that when a layer (or film), a region, a pattern, or a structure is referred to as being ‘on’ a substrate, a layer (or film), a region, a pad, or patterns, it can be directly on another layer or substrate, or intervening layers may also be present. Further, it will be understood that when a layer is referred to as being ‘under’ another layer, it can be directly under another layer, and one or more intervening layers may also be present. Further, the reference about ‘on’ and ‘under’ each layer will be made on the basis of drawings. 
     Hereinafter, embodiments will be described with reference to accompanying drawings. In the drawings, the thickness or size of each layer is exaggerated, omitted, or schematically illustrated for convenience in description and clarity. Also, the size of each element does not entirely reflect an actual size. 
       FIG. 1  is a side sectional view of a light emitting device according to a first embodiment, and  FIG. 2  is a plan view illustrating the light emitting device of  FIG. 1 . 
     Referring to  FIGS. 1 and 2 , a light emitting device  100  according to a first embodiment may include a first electrode  175 , an adhesive layer  170  on the first electrode  175 , a reflective layer  160  on the adhesive layer  170 , an ohmic contact layer  150  on the reflective layer  160 , a channel layer  140  around a top surface of the adhesive layer  170 , a light emitting structure  135  disposed on the ohmic contract layer  150  and the channel layer  140  to generate light, a second electrode  115  on the light emitting structure  135 , and a reflective member  190  disposed on at least one side of the second electrode  115 . The light emitting structure  135  may include a first conductive type semiconductor layer  130 , an active layer  120 , and a second conductive type semiconductor layer  110 . 
     The first electrode  175  may support a plurality of layers thereon as well as serve as an electrode. The first electrode  175  together with the second electrode  115  may supply power to the light emitting structure  135 . 
     For example, the first electrode  175  may include at least one selected from the group consisting of Ti, Ni, Pt, Au, W, Cu, Mo, Cu-M, and carrier wafers (e.g., Si, Ge, GaAs, ZnO, SiC, and SiGe). 
     The first electrode  175  may have a thickness changed according to a design of the light emitting device  100 . For example, the first electrode  175  may have a thickness of about 30 μm to about 500 μm. 
     The first electrode  175  may be plated and/or deposited below the light emitting structure  135  or may adhere to light emitting structure  135  in a sheet form, but is not limited thereto. 
     The adhesive layer  170  may be disposed on the first electrode  175 . The adhesive layer  170  may be a bonding layer and disposed below the channel layer  140 . The adhesive layer  170  has exposed lateral surfaces. The adhesive layer  170  may contact the reflective layer  160 , ends of the ohmic contact layer  150 , and the channel layer  140  to serve as a medium for enhancing an adhesive force between the layers, e.g., between the channel layer  140 , the ohmic contact layer  150 , and the reflective layer  160  and the first electrode  175 . 
     The adhesive layer  170  may be formed of a barrier metal or a bonding metal. For example, the adhesive layer  170  may include at least one selected from the group consisting of Ti, Au, Sn, Ni, Cr, Ga, In, Bi, Cu, Ag, and Ta. 
     The reflective layer  160  may be disposed on the adhesive layer  170 . The reflective layer  160  may reflect light incident from the light emitting structure  135  to improve light extraction efficiency. 
     For example, the reflective layer  160  may include at least one selected from the group consisting of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, and Hf or an alloy thereof, but is not limited thereto. Also, the reflective layer  160  may have a multi-layered structure, which is formed by using the foregoing metals together with transparent conductive materials such as In—ZnO (IZO), Ga—ZnO (GZO), Al—ZnO (AZO), Al—Ga—ZnO (AGZO), In—Ga—ZnO (IGZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium tin oxide (IGTO), and aluminum tin oxide (ATO). That is, for example, the reflective layer  160  may have a multi-layered structure such as IZO/Ni, AZO/Ag, IZO/Ag/Ni, or AZO/Ag/Ni. 
     The ohmic contact layer  150  may be disposed on the reflective layer  160 . The ohmic contact layer  150  may contact the first conductive type semiconductor layer  130  to smoothly supply power to the light emitting structure  135 . 
     Particularly, the ohmic contact layer  150  may be formed of one selected from the transparent conductive materials and the foregoing metals. For example, the ohmic contact layer may have a single- or multi-layered structure, which is formed by using at least one selected from the group consisting of indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), indium gallium tin oxide (IGTO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), IrOx, RuOx, RuOx/ITO, Ni, Ag, Ni/IrOx/Au, and Ni/IrOx/Au/ITO. 
     The ohmic contact layer  150  may have an end contacting the adhesive layer  170 . The ohmic contact layer  150  may contact the entire region of the first conductive type semiconductor layer  130  except a region of the first conductive type semiconductor layer  130  overlapping with the channel layer  140 . As described above, since the ohmic contact layer  150  contacts the first conductive type semiconductor layer  130  over as wide area as possible, current may be uniformly supplied to the active layer  120  through the entire region of the first conductive type semiconductor layer  130  contacting the ohmic contact layer  150 . Thus, light emitting efficiency may be significantly improved. 
     A current blocking layer (CBL)  145  may be disposed on the ohmic contact layer  150  to contact the first conductive type semiconductor layer  130 . At least portion of the CBL  145  may vertically overlap with the second electrode  115 . The CBL  145  may block the current supplied into the first conductive type semiconductor layer  130  through the ohmic contact layer  150 . Thus, the supply of the current supplied into the first conductive type semiconductor layer  130  may be blocked at and around the CBL  145 . That is, the CBL  145  may maximally prevent the current from concentrately flowing along the shortest path between the first electrode  175  and the second electrode  115 . As a result, the current flows into a region between the ohmic contact layer  150  and the first conductive type semiconductor layer  130  except the CBL  145 . Thus, since the current uniformly flows into the entire region of the first conductive type semiconductor layer  145 , the light emitting efficiency may be significantly improved. 
     Although it maximally prevents the current from flowing along the shortest path between the first electrode  175  and the second electrode  115  by the CBL  145 , the current flowing through the circumference of the CBL  145  flows into the shortest path between the first electrode  175  and the second electrode  115  in the first conductive type semiconductor layer  130  contacting the CBL  145 . Thus, the current having the same or similar distribution flows into the shortest path between the first electrode  175  and the second electrode  115  and the region of the first conductive type semiconductor layer  145  except the shortest path. 
     The CBL  145  may be formed of a material having conductivity or insulativity less than that of the ohmic contact layer  150  or a material, which short-circuit contacts the first conductive type semiconductor layer  130 . The CBL  145  may include at least one selected from the group consisting of ITO, IZO, IZTO, IAZO, IGZO, IGTO, AZO, ATO, ZnO, SiO 2 , SiO x , SiO x N y , Si 3 N 4 , Al 2 O 3 , TiO x , Ti, Al, and Cr. 
     The CBL  145  may be disposed between the ohmic contact layer  150  and the first conductive type semiconductor layer  130  or between the reflective layer  160  and the ohmic contact layer  150 , but is not limited thereto. 
     Also, the CBL  146  may be disposed inside a groove defined in the ohmic contact layer  150 , may protrude from the ohmic contact layer  150 , or may be disposed inside a hole passing through top and bottom surfaces of the ohmic contact layer  150 , but is not limited thereto. 
     The channel layer  140  may be disposed on a circumference region of a top surface of the adhesive layer  170 . That is, the channel layer  140  may be disposed on a circumference region between the light emitting structure  135  and the adhesive layer  170 . 
     The channel layer  140  may be formed of a material having insulativity or a material having conductivity less than that of the light emitting structure  135 . For example, the channel layer  140  may be formed of at least one selected from a group of consisting of SiO 2 , Si x O y , Si 3 N 4 , Si x N y , SiO x N y , Al 2 O 3 , TiO 2 . In this case, it may prevent the light emitting structure  135  and the first electrode  175  from being electrically short-circuited therebetween. Thus, reliability of the light emitting device  100  may be improved. 
     Alternatively, the channel layer  140  may be formed of a metal material having a superior adhesive force, for example, at least one selected from the group consisting of Ti, Ni, Pt, Pd, Rh, Ir, and W. In this case, the channel layer  140  may enhance an adhesive force between the light emitting structure  135  and the adhesive layer  170  to improve the reliability of the light emitting device  100 . Also, since the channel layer  140  is not broken or broken pieces of the channel layer  140  are not generated in a chip separation process such as a laser scribing process in which a plurality of chips is divided into individual chip units and a laser lift off (LLO) process in which a substrate is removed, the reliability of the light emitting device  100  may be improved. Also, in case where the channel layer  140  ohmic-contacts the first conductive type semiconductor layer  130 , since current may flow through the channel layer  140 , light may be generated in the active layer  120  vertically overlapping with the channel layer  140 . Thus, the light emitting efficiency of the light emitting device  100  may be further improved. For example, when the first conductive type semiconductor layer  130  is a p-type semiconductor layer, the channel layer  140  may be formed of a metal such Ti, Ni, and W, which form an ohmic-contact with respect to the p-type semiconductor, but is not limited thereto. 
     The light emitting structure  135  may be disposed on the ohmic contact layer  150  and the channel layer  140 . 
     The light emitting structure  135  has lateral surfaces vertically or inclinedly formed by an isolation etching process in which the plurality of chips is divided into individual chip units. Also, a portion of a top surface of the channel layer  140  may be exposed. 
     The light emitting structure  135  may be formed of a plurality of group III-V compound semiconductor materials. 
     The light emitting structure  135  may include the first conductive type semiconductor layer  130 , the active layer  120  on the first conductive type semiconductor layer  130 , and the second conductive type semiconductor layer  110  on the active layer  120 . 
     The first conductive type semiconductor layer  130  may be disposed on a portion of a region of the channel layer  140 , the ohmic contact layer  150 , and the CBL  145 . The first conductive type semiconductor layer  130  may be a p-type semiconductor layer, which is doped with a p-type dopant. The p-type semiconductor layer may be formed of at least one of group III-V compound semiconductor materials, for example, at least one selected from the group consisting of GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. The p-type dopant may be one of Mg, Zn, Ga, Sr, and Ba. The first conductive type semiconductor layer  130  may have a single- or multi-layered structure, but is not limited thereto. 
     The first conductive type semiconductor layer  130  may supply a plurality of carriers to the active layer  120 . 
     The active layer  120  may be disposed on the first conductive type semiconductor layer  130 . The active layer  120  may have at least one of a single quantum well structure, a multi quantum well (MQW) structure, a quantum wire structure, and a quantum dot structure, but is not limited thereto. 
     The active layer  120  may be formed at a cycle of a well layer and a barrier layer by using group III-V compound semiconductor materials. GaN, InGaN, and AlGaN may be used as component semiconductor materials for forming the active layer  120 . Thus, the active layer  120  may be formed at a cycle of an InGaN well layer/GaN barrier layer, an InGaN well layer/AlGaN barrier layer, or an InGaN well layer/InGaN barrier layer, but is not limited thereto. 
     The active layer  120  may recombine a plurality of holes supplied from the first conductive type semiconductor layer  130  with a plurality of electrons supplied from the second conductive type semiconductor layer  110  to generate light having a wavelength corresponding to that of a band gap depending on a semiconductor material of the active layer  120 . 
     Although not shown, a conductive clad layer may be disposed above and/or below the active layer  120 . The conductive clad layer may be formed of an AlGaN-based semiconductor. For example, a p-type clad layer, which is doped with a p-type dopant may be disposed between the first conductive type semiconductor layer  130  and the active layer  120 . Also, an n-type clad layer, which is doped with an n-type dopant may be disposed between the active layer  120  and the second conductive type semiconductor layer  110 . 
     The conductive clad layer may serve as a stopper by which the plurality of holes and electrons supplied from the active layer  120  are not transferred into the first and second conductive type semiconductor layers  130  and  110 . Thus, the holes and electrons supplied from the active layer  120  may be further recombined with each other by the conductive clad layer to improve the light emitting efficiency of the light emitting device  100 . 
     The active layer  120  may be disposed on the second conductive type semiconductor layer  110 . The second conductive type semiconductor layer  110  may be an n-type semiconductor layer, which is doped with the n-type dopant. The second conductive type semiconductor layer  110  may be formed of at least one of group III-V compound semiconductor materials, for example, at least one selected from the group consisting of GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. The n-type dopant may be one of Si, Ge, Sn, Se, and Te. The second conductive type semiconductor layer  110  may have a single- or multi-layered structure, but is not limited thereto. 
     A roughness or unevenness  112  may be disposed on the second conductive type semiconductor layer  110  to improve the light emitting efficiency. The roughness or unevenness  112  may have a random pattern shape formed by a wet etch process or a periodic pattern shape similar to a photonic crystal structure formed by a patterning process, but is not limited thereto. 
     The roughness or unevenness  112  may periodically have a concave shape and a convex shape. Each of the concave shape and the convex shape may have a rounded surface or both inclined surfaces, which are met at an apex thereof. 
     An n-type semiconductor layer may be disposed below the first conductive type semiconductor layer  130 . Since the first conductive type semiconductor layer  130  is the p-type semiconductor layer and the second conductive type semiconductor layer  110  is the n-type semiconductor layer, the light emitting structure may have at least one of an N-P junction structure, a P-N junction structure, an N-P-N junction structure, and a P-N-P junction structure. 
     The second electrode  115  may be disposed on a top surface of the light emitting structure  135 . The second electrode  115  may include a current spreading pattern  116   b , which spreads current to uniformly supply the current into an electrode pad region  116   a  to which a wire is bonded and the entire region of the light emitting structure  135  by being branched into at least one or more sides from the electrode pad region  116   a.    
     The electrode pad region  116   a  may have a square shape, a circular shape, an oval shape, or a polygonal shape, but is not limited thereto. 
     The second electrode  115  may have a single- or multi-layered structure including at least one selected from the group consisting of Au, Ti, Ni, Cu, Al, Cr, Ag, and Pt. Also, the second electrode  115  may have a thickness h of about 1 μm to about 10 μm, particularly, about 2 μm to about 5 μm. 
     Examples of the multi-layered structure of the second electrode  115  may include an ohmic layer formed of a metal such as Cr to ohmic-contact the light emitting structure  130  in a first layer that is the lowest layer, a reflective layer formed of a metal such as Al or Ag and having a high reflectance property in a second layer disposed on the first layer, a first diffusion barrier layer formed of a metal such as Ni for preventing interlayer diffusion in a third layer disposed on the second layer, a conductive layer formed of a metal such as Cu and having high conductivity in a fourth layer disposed on the third layer, a second diffusion barrier layer formed of a metal such as Ni for preventing interlayer diffusion in a fifth layer disposed on the fourth layer, and an adhesive layer  170  formed of a metal such as Au or Ti having a high adhesive force to easily bond a wire, but are not limited thereto. 
     Also, the electrode pad region  116   a  and the current spreading pattern  116   b  may have the same stacked structure or stacked structures different from each other. For example, since the current spreading pattern  116   b  does not require the adhesive layer for wire-bonding, the adhesive layer may not be provided. Also, the current spreading pattern  116   b  may be formed of a material having transmittance and conductivity, e.g., including at least one selected from the group consisting of ITO, IZO, IZTO, IAZO, IGZO, IGTO, AZO, ATO, and ZnO. 
     When the roughness or unevenness  112  is disposed on the top surface of the light emitting structure  135 , a roughness or unevenness having a shape equal or similar to that of the roughness or unevenness  112  may be naturally disposed on a top surface of the second electrode  115  by the roughness or unevenness  112 . The roughness or unevenness of the second electrode  115  may allow the reflective member  190  (that will be described later) to be firmly coupled to the second electrode  115 . 
     The reflective member  190  may be disposed on at least one lateral surface of the second electrode  115 . 
     Since the lateral surface of the second electrode  115  has a vertical surface, a lateral surface of the reflective member  190  disposed on the lateral surface of the second electrode  115  may also have a vertical surface equal or similar to that of the second electrode  115 . 
     The reflective member  190  may minimize a phenomenon in which light extracted through the top surface of the light emitting structure  135  is absorbed by the lateral surface of the second electrode  115 . Specifically, since the second electrode  115  has a relatively thicker thickness of about 1 μm to about 10 μm, particularly, about 2 μm to about 5 μm, an amount of the light absorbed into the lateral surface of the second electrode  115  in the light extracted through the top surface of the light emitting structure  135  can in no way be negligible in an aspect of the light extraction efficiency. Thus, since the reflective member  190  that may reflect the entire light from at least lateral surface of the second electrode  115  is disposed, the light extraction efficiency of the light emitting device  100  may be significantly improved. 
     The reflective member  190  may have a thickness of about 1 μm to about 10 μm according to its manufacturing process. When the reflective member  190  has a thickness of less than about 10 μm, the thickness of the reflective member  190  becomes much thinner to reduce the reflectance property. Thus, the light may be absorbed into the second electrode  115  through the reflective member  190  as ever. When the reflective member  190  has a thickness of greater than about 10 μm, the thickness of the reflective member  190  becomes much thicker to reduce a light extraction region of the light emitting structure  135 . Thus, the light extraction efficiency may be reduced. For example, the reflective member  190  may be formed of at least one or two or more alloys of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, and Hf. 
       FIG. 3  is an enlarged view illustrating various formation structures of the second electrode and the reflective member in the light emitting device according to the first embodiment. 
     Referring to  FIG. 3A , the reflective member  190  may be disposed on the entire region of the lateral surface and a circumference region of the top surface of the second electrode  115 , particularly, the electrode pad region  116   a . Also, the reflective member  190  may extend to contact a top surface of the second conductive type semiconductor layer  110 . The roughness or unevenness  112  equal or similar to the roughness or unevenness  112  disposed on the top surface of the second electrode  115  may be transferred onto the top surface of the reflective member  190  by the roughness or unevenness  112  disposed on the top surface of the second electrode  115 , but is not limited thereto. 
     Referring to  FIG. 3B , the reflective member  190  may be disposed on the entire region of the lateral surface and a circumference region of the top surface of the second electrode  115 , particularly, the electrode pad region  116   a . Also, the reflective member  190  may extend to contact the top surface of the second conductive type semiconductor layer  110 . An adhesive layer  195  may be disposed between the reflective member  190  and the second electrode  115 , particularly, the electrode pad region  116   a  to improve an adhesive force therebetween. The adhesive layer  195  may be formed of a metal material having a superior adhesive force such as Ni, Pt, or Ti. 
     Referring to  FIG. 3C , the reflective member  190  may be disposed on a portion of the lateral surface and the circumference region of the top surface of the second electrode  115 , particularly, the electrode pad region  116   a . Also, the reflective member  190  may not contact the top surface of the second conductive type semiconductor layer  110 . That is to say, the reflective member  190  may extend from the circumference region of the top surface of the electrode pad region  116   a  to the portion of the lateral surface of the second electrode  115 . The portion of the lateral surface of the electrode pad region  116   a  may be spaced from the top surface of the second conductive type semiconductor layer  110 . The formation structure of the reflective member  190  may result from a mask disposed on the second conductive type semiconductor layer  110  in the process of forming the reflective member  190 . 
     The reflective member  190  may be disposed to expose a portion of the top surface of the electrode pad region  116   a . That is to say, the portion of the top surface of the electrode pad region  116   a  may not be covered by the reflective member  190 . That is, the reflective member may not be disposed in a region in which the wire is bonded on the electrode pad region  116   a.    
     Referring again to  FIGS. 1 and 2 , a passivation layer  180  may be formed on at least lateral surface of the light emitting structure  135 . Particularly, the passivation layer  180  may have one end formed on the circumference region of the top surface of the second conductive type semiconductor layer  110  and the other end by way via or passing through the lateral surface of the light emitting structure  135  and formed on a top surface of the channel layer  140 , but is not limited thereto. That is to say, the passivation layer  180  may extend from the top surface of the channel layer  140  to the circumference region of the top surface of the second conductive type semiconductor layer  110  via the lateral surfaces of the first conductive type semiconductor layer  130 , the active layer  120 , and the second conductive type semiconductor layer  110 . 
     The passivation layer  180  may prevent electrical short circuit from occurring between the light emitting structure  135  and a conductive member such as an external electrode. For example, the passivation layer  180  may be formed of a material having insulativity such as SiO 2 , SiO x , SiO x N y , Si 3 N 4 , TiO 2 , or Al 2 O 3 , but is not limited thereto. 
     Hereinafter, a method of manufacturing a light emitting device according to an embodiment will be described in detail. However, explanations duplicated with the foregoing explanations will be omitted or simply described. 
       FIGS. 4 to 14  are views illustrating a process of manufacturing the light emitting device according to the first embodiment. 
     Referring to  FIG. 4 , a light emitting structure  135  may be formed on a substrate  101 . 
     For example, the substrate  101  may include at least one selected from the group consisting of sapphire (Al 2 O 3 ), SiC, GaAs, GaN, ZnO, Si, GaP, InP, and Ge, but is not limited thereto. 
     A second conductive type semiconductor layer  110 , an active layer  120 , and a first conductive type semiconductor layer  130  may be sequentially grown on the substrate  101  to form the light emitting structure  135 . 
     For example, the light emitting structure  135  may be formed using at least one of a metal organic chemical vapor deposition (MOCVD) process, a chemical vapor deposition (CVD) process, a plasma-enhanced chemical vapor deposition (PECVD) process, a molecular beam epitaxy (MBE) process, and a hydride vapor phase epitaxy (HVPE) process, but is not limited thereto. 
     A buffer layer (not shown) or an undoped semiconductor layer (not shown) may be formed between the light emitting structure  135  and the substrate  101  to reduce a lattice constant difference therebetween. 
     The buffer layer may include at least one selected from the group consisting of InAlGaN, GaN, AlGaN, InGaN, AlInN, AlN, or InN, but is not limited thereto. 
     Referring to  FIG. 5 , a channel layer  140  may be formed around a chip boundary region on the light emitting structure  135 , particularly, the first conductive type semiconductor layer  130 , i.e., a boundary region between a first chip region T 1  and a second chip region T 2 . The first chip region T 1  and the second chip region T 2  may be cut later by a scribing process to manufacture unit light emitting devices. Thus, each of the chip regions T 1  and T 2  may be defined as a region for obtaining a unit light emitting device. 
     The channel layer  140  may be formed around the boundary region between the first chip region T 1  and the second chip region T 2  using a mask pattern. Since the drawing is two-dimensionally illustrated,  FIG. 5  illustrates a structure in which the channel layer  140  is formed around any one chip region and the entire boundary region between all chip regions contacting the chip region. Thus, when viewed from an upper side, the channel layer  140  may have a ring shape, a loop shape, or a frame shape. The channel layer  140  may be formed using various deposition processes such as a sputtering process, an E-beam deposition process, and a plasma enhanced chemical vapor deposition (PECVD) process. 
     The channel layer  140  may be formed of a material having insulativity such as SiO 2 , Si x O y , Si 3 N 4 , Si x N y , SiO x N y , Al 2 O 3 , or TiO 2 , or a metal material having a superior adhesive force such as Ti, Ni, Pt, Pd, Rh, Ir, or W. Thus, the channel  140  may prevent electrical short circuit from occurring between the light emitting structure  135  and the first electrode  175  or enhance the adhesive force between the light emitting structure  135  and an adhesive layer  170  to improve reliability of a light emitting device  100 . 
     Referring to  FIG. 6 , a current blocking layer (CBL)  145  may be formed on the first conductive type semiconductor layer  130 . The CBL  145  may be formed using a mask pattern. The CBL  145  may be formed on the first conductive type semiconductor layer  130  in which at least portion thereof vertically overlaps with a second electrode  115  that will be formed by a post-process. 
     The CBL  145  may be formed of a material having conductivity or insulativity less than that of the ohmic contact layer  150  or a material, which short-circuit contacts the first conductive type semiconductor layer  130 . The CBL  145  may include at least one selected from the group consisting of ITO, IZO, IZTO, IAZO, IGZO, IGTO, AZO, ATO, ZnO, SiO 2 , SiO x , SiO x N y , Si 3 N 4 , Al 2 O 3 , TiO x , Ti, Al, and Cr. 
     Referring to  FIGS. 7 and 8 , an ohmic contact layer  150  may be formed on top surfaces of the first conductive type semiconductor layer  130  and the CBL  145  and portions of lateral and top surfaces of the channel layer  140 . A reflective layer  160  may be formed on the ohmic contact layer  150 . 
     The ohmic contact layer  150  may be formed of one selected from the transparent conductive materials and the foregoing metals. For example, the ohmic contact layer may have a single- or multi-layered structure, which is formed by using at least one selected from the group consisting of indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), indium gallium tin oxide (IGTO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), IrOx, RuOx, RuOx/ITO, Ni, Ag, Ni/IrOx/Au, and Ni/IrOx/Au/ITO. 
     For example, the reflective layer  160  may include at least one selected from the group consisting of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, and Hf or an alloy thereof, but is not limited thereto. Also, the reflective layer  160  may have a multi-layered structure, which is formed by using the foregoing metals together with transparent conductive materials such as In—ZnO (IZO), Ga—ZnO (GZO), Al—ZnO (AZO), Al—Ga—ZnO (AGZO), In—Ga—ZnO (IGZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium tin oxide (IGTO), or aluminum tin oxide (ATO). That is, for example, the reflective layer  160  may have a multi-layered structure such as IZO/Ni, AZO/Ag, IZO/Ag/Ni, or AZO/Ag/Ni. 
     For example, each of the ohmic contact layer  150  and the reflective layer  160  may be formed using any one of a sputtering process, an E-beam deposition process, and a plasma enhanced chemical vapor deposition (PECVD) process. 
     Referring to  FIG. 9 , the adhesive layer  170  may be formed on the reflective layer  160  and the channel layer  140 , and the first electrode  175  may be formed on the adhesive layer  170 . 
     The adhesive layer  170  may be formed of a barrier metal or a bonding metal. For example, the adhesive layer  170  may include at least one selected from the group consisting of Ti, Au, Sn, Ni, Cr, Ga, In, Bi, Cu, Ag, and Ta. 
     For example, the first electrode  175  may include at least one selected from the group consisting of Ti, Ni, Pt, Au, W, Cu, Mo, Cu-M, and carrier wafers (e.g., Si, Ge, GaAs, ZnO, SiC, and SiGe). 
     The first electrode  175  may be formed using a plating process or a deposition process, but is not limited thereto. 
     A separate sheet may be prepared to adhere to the adhesive layer  170  using a bonding process, thereby forming the first electrode  175 . 
     Referring to  FIG. 11 , the substrate  101  may be turned upside down (180°), and then, the substrate  101  may be removed. 
     The substrate  101  may be removed by at least one of a laser lift off (LLO) method, a chemical lift off (CLO) method, and a physical polishing method. 
     According to the LLO method, a laser is concentrately irradiated onto an interface between the substrate  101  and the second conductive type semiconductor layer  110  to separate the substrate  101  from the second conductive type semiconductor layer  110 . 
     According to the LLO method, the substrate  101  is removed so that the second conductive type semiconductor layer  110  is exposed using a wet etch process. 
     According to the physical polishing method, the substrate  101  is physically polished to sequentially remove the substrate  101  from a top surface thereof so that the second conductive type semiconductor layer  110  is exposed. 
     After the substrate  101  is removed, a cleaning process may be further performed to remove a residual of the substrate  101  remaining on the top surface of the second conductive type semiconductor layer  110 . The cleaning process may include an ashing process, which uses a plasma surface treatment or oxygen or nitrogen gas. 
     Referring to  FIG. 11 , an isolation etching process may be performed along a boundary region between first and second chip regions T 1  and T 2  to divide a unit chip region including the light emitting structure  135 . The channel layer  140  in the boundary region between the first and second chip regions T 1  and T 2  may be exposed by the isolation etching process. 
     For example, the isolation etching process may be performed by a dry etch process such as an inductively coupled plasma (ICP) process. 
     Referring to  FIG. 12 , a passivation layer  180  may be formed on at least lateral surface of the light emitting structure  135  and the channel layer  140  in the boundary region between the first and second chip regions T 1  and T 2 . That is to say, the passivation layer  180  may contact the top surface of the channel layer  140  in the boundary region between the first and second chip regions T 1  and T 2 . Also, the passivation layer  180  may extend up to the circumference region of the top surface of the second conductive type semiconductor layer  110  by way via or passing through the lateral surfaces of the first conductive type semiconductor layer  130 , the active layer  120 , and the second conductive type semiconductor layer  110 . 
     The passivation layer  180  may prevent electrical short circuit from occurring between the light emitting structure  135  and a conductive member such as an external electrode. For example, the passivation layer  180  may be formed of a material having insulativity such as SiO 2 , SiO x , SiO x N y , Si 3 N 4 , TiO 2 , or Al 2 O 3 , but is not limited thereto. 
     The passivation layer  180  may be formed by a deposition process such as an E-beam deposition process, a PECVD process, or a sputtering process. 
     A roughness or unevenness  112  may be formed on the top surface of the second conductive type semiconductor layer  110  exposed by the passivation layer  180  to improve light extraction efficiency. 
     A dry or wet etch process may be performed using the passivation layer  180  as a mask to form the roughness or unevenness  112 . Any roughness or unevenness is not formed on the second conductive type semiconductor layer  110  below the passivation layer  180  by the passivation layer  180 . 
     Although a process of forming the roughness or unevenness on the second conductive type semiconductor layer  110  after the passivation layer  180  is formed in  FIG. 12 , the roughness or unevenness may be formed on the second conductive type semiconductor layer  110  before the passivation layer  180  is formed. In this case, the roughness or unevenness may be formed on the entire lateral surfaces of the second conductive type semiconductor layer  110 , the active layer  120 , and the first conductive type semiconductor layer  130  as well as the top surface of the second conductive type semiconductor layer  110 . 
     Embodiments are not limited to a given order of forming the passivation layer  180  and the roughness or unevenness  112  formed on the second conductive type semiconductor layer  110 . 
     A second electrode may be formed on the second conductive type semiconductor layer  110  including the roughness or unevenness  112 . 
     The second electrode  115  may include an electrode pad region  116   a  to which a wire is bonded and a current spreading pattern  116   b , which spreads current to uniformly supply the current into the entire region of the light emitting structure  135  by being branched into at least one or more sides from the electrode pad region  116   a.    
     The electrode pad region  116   a  may have a square shape, a circular shape, an oval shape, or a polygonal shape, but is not limited thereto. 
     The second electrode  115  may have a single- or multi-layered structure including at least one selected from the group consisting of Au, Ti, Ni, Cu, Al, Cr, Ag, and Pt. 
     The second electrode  115  may be formed using a plating process or a deposition process. 
     Referring to  FIG. 13 , a reflective member  190  may be formed on at least lateral surface of the second electrode  115 . 
     The reflective member  190  may be formed on the entire region of the lateral surface and the circumference region of the top surface of the second electrode  115 , particularly, the electrode pad region  116   a.    
     For example, the reflective member  190  may be formed of at least one or two or more alloys of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, and Hf. 
     The reflective member  190  may be formed by the deposition process such as the E-beam deposition process, the PECVD process, or the sputtering process or may be formed by the plating process. 
     The reflective member  190  may be formed after a mask is formed on the light emitting structure  135 . In this case, it may prevent the light emitting structure  135  from being damaged by the process of manufacturing the reflective member  190 . 
     Also, in case where the adhesive layer  195  is formed between the reflective member  190  and the second electrode  115  (refer to  FIG. 3B ), the adhesive layer  195  may be formed on at least one lateral surface of the second electrode  115  before the reflective member  190  is formed. 
     Referring to  FIG. 14 , a chip separation process may be performed to cut the boundary region between the first and second chip regions T 1  and T 2 . As a result, since a plurality of chips is divided into individual chip units, the light emitting device  100  according to an embodiment may be manufactured. 
     For example, the chip separation process may include a breaking process in which a physical force using a blade is applied to separate the chips, a laser scribing process in which a laser is irradiated onto a boundary between the chips to separate the chips, and an etch process including a wet or dry etch process, but is not limited thereto. 
       FIG. 15  is a side sectional view of a light emitting device according to a second embodiment, and  FIG. 16  is a plan view illustrating the light emitting device of  FIG. 15 . 
     A second embodiment is equal or similar to the first embodiment except that a reflective member  190  is disposed on at least lateral surface of an electrode pad region  116   a  of a second electrode  115  as well as on the entire surface of a current spreading pattern  116   b  except an under surface of the current spreading pattern  116   b  of the second electrode  115 . 
     Thus, equivalent parts of the second embodiment are given the same term or reference number as in the first embodiment. 
     In addition, the same contents as those of the first embodiment will not be described in detail in the second embodiment. The contents, which are not described in the second embodiment, may be easily understood from the first embodiment. 
     Referring to  FIGS. 15 and 16 , in a light emitting device  100 A according to the second embodiment, the reflective member  190  may be disposed on at least lateral surface of the electrode pad region  116   a  of the second electrode  115  as well as on the entire surface of the current spreading pattern  116   b  except the under surface of the current spreading pattern  116   b  of the second electrode  115 . 
     That is to say, the reflective member  190  may cover a top surface and both lateral surfaces of the current spreading pattern  116   b.    
     According to the second embodiment, the reflective member  190  may be further disposed on the entire surface of the current spreading pattern  116   b  except the under surface of the current spreading pattern  116   b . Thus, since light extracted through a second conductive type semiconductor layer  110  is totally reflected by the reflective member  190  disposed on the at least lateral surface of the current spreading pattern  116   b , light losses may be minimized when compared to that of the first embodiment and light extraction efficiency may be improved. 
       FIG. 17  is a side sectional view of a light emitting device according to a third embodiment. 
     A third embodiment is equal or similar to the first embodiment except that a second electrode  115  has an inclined lateral surface, and also a reflective member  190  disposed on the lateral surface of the second electrode  115  is inclinedly disposed on the lateral surface of the second electrode  115 . 
     Thus, equivalent parts of the third embodiment are given the same term or reference number as in the first embodiment. 
     In addition, the same contents as those of the first embodiment will not be described in detail in the third embodiment. The contents, which are not described in the third embodiment, may be easily understood from the first embodiment. 
     Referring to  FIG. 17 , in a light emitting device  100 B according to the third embodiment, the second electrode  115  may have an inclined lateral surface. That is, the second electrode  115  may have an under surface having a width greater than that of a top surface thereof. 
     Similarly, since the second electrode  115  has the inclined lateral surface, the reflective member  190  disposed on the lateral surface of the second electrode  115  may also have an inclined surface equal or similar to that of the second electrode  115 . 
     In addition, the reflective member  190  may be disposed around a circumference region of the top surface of the second electrode  115 , like the first embodiment. Also, the reflective member  190  may contact a second conductive type semiconductor layer  110  or may be spaced from the second conductive type semiconductor layer  110 . 
     Thus, since the reflective member  190  has the inclined lateral surface, light extracted through the second conductive type semiconductor layer  110  may be reflected by the inclined surface of the reflective member  190  to improve light extraction efficiency. 
       FIG. 18  is a side sectional view of a light emitting device according to a fourth embodiment. 
     A fourth embodiment is equal or similar to the third embodiment except that a roughness or unevenness is disposed on each of lateral surfaces of a second electrode  115  and a reflective member  190 . 
     Thus, equivalent parts of the fourth embodiment are given the same term or reference number as in the third embodiment. 
     In addition, the same contents as those of the first and third embodiments will not be described in detail in the fourth embodiment. The contents, which are not described in the fourth embodiment, may be easily understood from the first and third embodiments. 
     Referring to  FIG. 18 , in a light emitting device  100 C according to the fourth embodiment, the second electrode  115  may have an inclined lateral surface. Also, the roughness or unevenness may be disposed on each of top and lateral surfaces of the second electrode  115 . 
     The second electrode  115  may have an under surface having a width greater than that of the top surface thereof. 
     In addition, the second electrode  115  may have the inclined lateral surface, and also, the roughness or unevenness may be disposed on the inclined lateral surface of the second electrode  115 . 
     Similarly, since the second electrode  115  has the inclined lateral surface and the roughness or unevenness is disposed on the inclined lateral surface of the second electrode  115 , the reflective member  190  disposed on the lateral surface of the second electrode  115  may also have a roughness or unevenness equal or similar to that of the second electrode  115 . 
     Thus, since the reflective member  190  has the inclined lateral surface, light extracted through a second conductive type semiconductor layer  110  may be reflected by the inclined surface of the reflective member  190  to improve light extraction efficiency. Also, since the roughness or unevenness may be disposed on the lateral surface of the reflective member  190 , the light extracted through the second conductive type semiconductor layer  110  may be randomly reflected by the roughness or unevenness of the reflective member  190 . As a result, the light may uniformly proceed in all directions of a light emitting structure  135  to improve light uniformity. 
       FIG. 19  is a sectional view of a light emitting device package including a light emitting device according to an embodiment. 
     Referring to  FIG. 19 , a light emitting device package  30  according to an embodiment includes a body part  20 , first and second electrode layers  31  and  32  disposed on the body part  20 , a light emitting device  1  disposed on the body part  20  and electrically connected to the first and second electrode layers  31  and  32 , and a molding member  40  surrounding the light emitting device  1  on the body part  20 . 
     The body part  20  may be formed of a silicon material, a synthetic resin material, or a metal material. Also, when viewed from an upper side, the body part  20  has a cavity  50  therein, and the cavity  50  has an inclined surface  53 . 
     The first electrode layer  31  and the second electrode layer  32  may be electrically separated from each other and pass through the inside of the body part  20 . That is, each of the first and second electrode layers  31  and  32  has one end disposed inside the cavity  50  and the other end attached to an outer surface of the body part  20  and exposed to the outside. 
     The first and second electrode layers  31  and  32  may provide power to the light emitting device  1 . Also, the first and second electrode layers  31  and  32  may reflect light generated in the light emitting device  1  to improve light efficiency. In addition, the first and second electrode layers  31  and  32  may discharge heat generated in the light emitting device  1  to the outside. 
     The light emitting device  1  may be disposed on the body part  20  or the first or second electrode layer  31  or  32 . 
     First and second wires  171  and  181  of the light emitting device  1  may be electrically connected to one of the first and second electrode layers  31  and  32 , but is not limited thereto. 
     The molding member  40  may surround the light emitting device  1  to protect the light emitting device  1 . Also, a phosphor may be contained in the molding member  40  to change a wavelength of light emitted from the light emitting device  1 . 
     The light emitting device or the light emitting device package according to an embodiment may be applied to a light unit. The light unit has a structure in which a plurality of light emitting devices or light emitting device packages is arrayed. Thus, the light unit may include a display device illustrated in  FIGS. 20 and 21  and a lighting device illustrate in  FIG. 22 . In addition, the light unit may include illumination lamps, traffic lights, vehicle headlights, and signs. 
       FIG. 20  is an exploded perspective view of a display device according to am embodiment. 
     Referring to  FIG. 20 , a display unit  1000  may include a light guide plate  1041 , a light emitting module  1031  providing light to the light guide plate  1041 , a reflective member  1022  below the light guide plate  1041 , an optical sheet  1051  above the light guide plate  1041 , a display panel  1061  above the optical sheet  1051 , and a bottom cover  1011  receiving the light guide plate  1031 , the light emitting module  1031 , and the reflective member  1022 , but is not limited thereto. 
     The bottom cover  1011 , the reflective member  1022 , the light guide plate  1041  may be defined as the light unit  1050 . 
     The light guide plate  1041  diffuses light supplied from the light emitting module  1031  to produce planar light. The light guide plate  1041  may be formed of a transparent material. For example, the light guide plate  1041  may be formed of one of an acrylic resin-based material such as polymethylmethacrylate (PMMA), a polyethylene terephthalate (PET) resin, a poly carbonate (PC) resin, a cyclic olefin copolymer (COC) resin, and a polyethylene naphthalate (PEN) resin. 
     The light emitting module  1031  is disposed on at least one lateral surface of the light guide plate  1041  to provide light to the at least one lateral surface of the light guide plate  1041 . Thus, the light emitting module  1031  may be used as a light source of a display device. 
     At least one light emitting module  1031  may be disposed on one lateral surface of the light guide plate  1041  to directly or indirectly provide light. The light emitting module  1031  may include a substrate  1033  and the light emitting device packages  30  according to the embodiment. The light emitting device packages  30  may be arrayed by a predetermined distance on the substrate  1033 . The substrate  1033  may be a printed circuit board (PCB), but is not limited thereto. Also, the substrate  1033  may include a metal core PCB or a flexible PCB, but is not limited thereto. When the light emitting device packages  30  are mounted on a lateral surface of the bottom cover  1011  or on a heatsink plate, the substrate  1033  may be removed. Here, a portion of the heatsink plate may contact a top surface of the bottom cover  1011 . Thus, heat generated in the light emitting device package  30  may be discharged into the bottom cover  1011  via the heatsink plate. 
     The plurality of light emitting device packages  30  may be mounted to allow a light emitting surface through which light is emitted onto the substrate  1033  to be spaced a predetermined distance from the light guide plate  1041 , but is not limited thereto. The light emitting device packages  30  may directly or indirectly provide light to a light incident surface that is a side of the light guide plate  1041 , but is not limited thereto. 
     The reflective member  1022  may be disposed below the light guide plate  1041 . Since the reflective member  1022  reflects light incident onto an under surface of the light guide plate  1041  to supply the light to the display panel  1061 , brightness of the display panel  1061  may be improved. For example, the reflective member  1022  may be formed of one of PET, PC, and PVC, but is not limited thereto. The reflective member  1022  may be the top surface of the bottom cover  1011 , but is not limited thereto. 
     The bottom cover  1011  may receive the light guide plate  1041 , the light emitting module  1031 , and the reflective member  1022 . For this, the bottom cover  1011  may include a receiving part  1012  having a box shape with an opened upper side, but is not limited thereto. The bottom cover  1011  may be coupled to a top cover (not shown), but is not limited thereto. 
     The bottom cover  1011  may be formed of a metal material or a resin material. Also, the bottom cover  1011  may be manufactured using a press molding process or an extrusion molding process. The bottom cover  1011  may be formed of a metal or non-metal material having superior heat conductivity, but is not limited thereto. 
     For example, the display panel  1061  may be a liquid crystal display (LCD) panel, and include first and second substrates formed of a transparent material and a liquid crystal layer between the first and second substrates. A polarizing plate may be attached to at least one surface of the display panel  1061 . The present disclosure is not limited to the attached structure of the polarizing plate. The display panel  1061  transmits or blocks light provided from the light emitting module  1031  to display information. The display unit  1000  may be applied to various portable terminals, a monitor for a notebook computer, a monitor for a laptop computer, television, etc. 
     The optical sheet  1051  is disposed between the display panel  1061  and the light guide plate  1041  and includes at least one transmission sheet. For example, the optical sheet  1051  may include at least one of a diffusion sheet, a horizontal or vertical prism sheet, a brightness enhanced sheet, etc. The diffusion sheet diffuses incident light, and the horizontal or/and vertical prism sheet collects the incident light into a display region. In addition, the brightness enhanced sheet reuses lost light to improve the brightness. Also, a protection sheet may be disposed on the display panel  1061 , but is not limited thereto. 
     Optical members such as the light guide plate  1041  and the optical sheet  1051  may be disposed on an optical path of the light emitting module  1031 , but is not limited thereto. 
       FIG. 21  is a view of a display device according to an embodiment. 
     Referring to  FIG. 21 , a display unit  1100  includes a bottom cover  1152 , a substrate  1120  on which the above-described light emitting device packages  30  are arrayed, an optical member  1154 , and a display panel  1155 . 
     The substrate  1120  and the light emitting device package  30  may be defined as a light emitting module  1060 . The bottom cover  1152 , the at least one light emitting module  1060 , and the optical member  1154  may be defined as a lighting unit. 
     The bottom cover  1152  may include a receiving part  1153 , but is not limited thereto. 
     The optical member  1154  may include at least one of a lens, a light guide plate, a diffusion sheet, horizontal and vertical prism sheets, and a bright enhancement sheet. The light guide plate may be formed of a PC material or PMMA material. In this case, the light guide plate may be removed. The diffusion sheet diffuses incident light, and the horizontal and vertical prism sheets collect the incident light into the display panel  1155 . The brightness enhanced sheet reuses lost light to improve brightness. 
     The optical member  1154  is disposed on the light emitting module  1060  to produce planar light using the light emitted from the light emitting module  1060  or diffuse and collect the light emitted from the light emitting module  1060 . 
       FIG. 22  is a perspective view of a lighting device according to an embodiment. 
     Referring to  FIG. 22 , the lighting unit  1500  may include a case  1510 , a light emitting module  1530  in the case  1510 , and a connection terminal  1520  disposed in the case  1510  to receive an electric power from an external power source. 
     The case  1510  may be preferably formed of a material having good heat shielding characteristics, for example, a metal material or a resin material. 
     The light emitting module  1530  may include a substrate  1532  and a light emitting device package  30  mounted on the substrate  1532 . The light emitting device package  30  may be provided in plurality, and the plurality of light emitting device packages  30  may be arrayed in a matrix shape or spaced a predetermined distance from each other. 
     The substrate  1532  may be an insulator substrate on which a circuit pattern is printed. For example, the substrate may include a general printed circuit board (PCB), a metal core PCB, a flexible PCB, a ceramic PCB, FR-4, etc. 
     Also, the substrate  1532  may be formed of a material to efficiently reflect light, and a surface thereof may be formed in a color capable of efficiently reflecting light. For example, the substrate may be a coated layer having a white color or a silver color. 
     The at least one light emitting device packages  30  may be mounted on the substrate  1532 . Each of the light emitting device packages  30  may include at least one light emitting diode (LED) chip. The LED chip may include a color LED emitting red, green, blue or white light, and a UV LED emitting ultraviolet (UV) rays. 
     The light emitting module  1530  may have a combination of several light emitting device packages  30  to obtain desired color and luminance. For example, the light emitting module  1530  may have a combination of a white LED, a red LED, and a green LED to obtain a high color rendering index (CRI). 
     The connection terminal  1520  may be electrically connected to the light emitting module  1530  to supply a power. The connection terminal  1520  may be screwed and coupled to an external power source in a socket type, but is not limited thereto. For example, the connection terminal  1520  may be made in a pin type and inserted into an external power source, or may be connected to the external power source through a wire. 
     According to the embodiments, in the method of manufacturing the light emitting device, the first electrode is prepared, and the light emitting structure including the first semiconductor layer, the active layer, and the second semiconductor layer are disposed on the first electrode. Also, the second electrode is disposed on the light emitting structure, and the reflective member is disposed on the at least lateral surface of the second electrode. 
     According to the embodiments, since the reflective member is disposed on the at least lateral surface of the second electrode, the light extracted through the light emitting structure may be reflected by the reflective member to improve the light extraction efficiency of the light emitting device. 
     According to the embodiments, the second electrode includes the electrode pad region and the current spreading patterns, which are branched into at least one or more sides from the electrode pad region. Here, since the reflective member is disposed on the at least lateral surface of the electrode pad region, the light extracted through the light emitting structure may be reflected by the electrode pad region to improve the light extraction efficiency of the light emitting device. 
     According to the embodiments, since the adhesive layer is disposed between the second electrode and the reflective member, the reflective member may further strongly adhere to the second electrode by the adhesive layer. 
     According to the embodiments, since the reflective member is disposed on at least lateral surface of each of the current spreading patterns, the light extracted through the light emitting structure may be reflected by the electrode pad region as well as the current spreading patterns to significantly improve the light extraction efficiency. 
     According to the embodiments, since the lateral surface of the electrode has the inclined surface and the unevenness, the light extracted through the light emitting structure may be randomly reflected by the unevenness to realize more uniform light. 
     Any reference in this specification to “one embodiment,” “an embodiment,” “example embodiment,” etc., means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with any embodiment, it is submitted that it is within the purview of one skilled in the art to affect such feature, structure, or characteristic in connection with other ones of the embodiments. 
     Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art.