Patent Publication Number: US-9419184-B2

Title: Light-emitting device, light-emitting device package, and light unit

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a Continuation Application of prior U.S. patent application Ser. No. 14/405,447 filed Dec. 4, 2014, which is a U.S. National Stage Application under 35 U.S.C. §371 of PCT Application No. PCT/KR2013/004574, filed May 24, 2013, which claims priority to Korean Patent Application No. 10-2012-0061370, filed Jun. 8, 2012, whose entire disclosures are hereby incorporated by reference. 
    
    
     TECHNICAL FIELD 
     The embodiment relates to a light-emitting device, a light-emitting device package, and a light unit. 
     BACKGROUND ART 
     A light-emitting diode (LED) has been extensively used as one of light-emitting devices. The LED converts electrical signals into the form of light such as infra-red light, ultra-violet light, and visible light by using the characteristic of a compound semiconductor. 
     As the light efficiency of the light-emitting device is increased, the LED has been used in various fields such as display apparatuses and lighting appliances. 
     DISCLOSURE 
     Technical Problem 
     The embodiment provides a light-emitting device, a light-emitting device package, and a light unit, capable of improving light extraction efficiency. 
     Technical Solution 
     A light-emitting device according to the embodiment includes a light-emitting structure including a first conductive semiconductor layer, an active layer under the first conductive semiconductor layer, and a second conductive semiconductor layer under the active layer; a reflective electrode under the light-emitting structure; and an electrode arranged inside the first conductive semiconductor layer and comprising a conductive ion implantation layer. 
     A light-emitting device package according to the embodiment includes a body; a light-emitting device on the body; and first and second lead electrodes electrically connected to the light-emitting device, wherein the light-emitting device includes a light-emitting structure including a first conductive semiconductor layer, an active layer under the first conductive semiconductor layer, and a second conductive semiconductor layer under the active layer; a reflective electrode under the light-emitting structure; and an electrode arranged inside the first conductive semiconductor layer and comprising a conductive ion implantation layer. 
     A light unit according to the embodiment includes a substrate; a light-emitting device on the substrate; and an optical member serving as an optical path for light emitted from the light-emitting device, wherein the light-emitting device includes a light-emitting structure including a first conductive semiconductor layer, an active layer under the first conductive semiconductor layer, and a second conductive semiconductor layer under the active layer; a reflective electrode under the light-emitting structure; and an electrode arranged inside the first conductive semiconductor layer and comprising a conductive ion implantation layer. 
     Advantageous Effects 
     The light-emitting device, the light-emitting device package, and the light unit according to the embodiment can improve the light extraction efficiency. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  is a view showing a light-emitting device according to the embodiment. 
         FIG. 2  is a view showing an electrode part and a pad part of a light-emitting device according to the embodiment. 
         FIGS. 3 to 7  are views showing a method of fabricating a light-emitting device according to the embodiment. 
         FIGS. 8 and 9  are views showing a modified light-emitting device according to the embodiment. 
         FIG. 10  is a view showing a light-emitting device package according to the embodiment. 
         FIG. 11  is a view showing a display device according to the embodiment. 
         FIG. 12  is a view showing another example of the display device according to the embodiment. 
         FIGS. 13 to 15  are views showing a lighting apparatus according to the embodiment. 
         FIGS. 16 and 17  are views showing another example of a lighting apparatus according to the embodiment. 
     
    
    
     BEST MODE 
     Mode for Invention 
     In the description of the embodiments, it will be understood that, when a layer (or film), a region, a pattern, or a structure is referred to as being “on” or “under” another substrate, another layer (or film), another region, another pad, or another pattern, it can be “directly” or “indirectly” over the other substrate, layer (or film), region, pad, or pattern, or one or more intervening layers may also be present. Such a position of the layer has been described with reference to the drawings. 
     The thickness and size of each layer shown in the drawings may be exaggerated, omitted or schematically drawn for the purpose of convenience or clarity. In addition, the size of elements does not utterly reflect an actual size. 
     Hereinafter, a light-emitting device, a light-emitting device package, a light unit, and a method for fabricating the light-emitting device according to the embodiments will be described in detail with reference to accompanying drawings. 
       FIG. 1  is a view showing a light-emitting device according to the embodiment. 
     As shown in  FIG. 1 , the light-emitting device according to the embodiment may include a light-emitting structure  10 , a reflective electrode  17  and an electrode  80 . 
     The light-emitting structure  10  may include a first conductive semiconductor layer  11 , an active layer  12 , and a second conductive semiconductor layer  13 . The active layer  12  may be interposed between the first conductive semiconductor layer  11  and the second conductive semiconductor layer  13 . The active layer  12  may be provided under the first conductive semiconductor layer  11 , and the second conductive semiconductor layer  13  may be provided under the active layer  12 . 
     For instance, the first conductive semiconductor layer  11  may include an N-type semiconductor layer doped with N-type dopants serving as first conductive dopants, and the second conductive semiconductor layer  13  may include a P-type semiconductor layer doped with P-type dopants serving as second conductive dopants. In addition, the first conductive semiconductor layer  11  may include a P-type semiconductor layer, and the second conductive semiconductor layer  13  may include an N-type semiconductor layer. 
     For example, the first conductive semiconductor layer  11  may include an N-type semiconductor layer. The first conductive semiconductor layer  11  may be realized by using a compound semiconductor. The first conductive semiconductor layer  11  may be realized by using a group II-VI compound semiconductor, or a group III-V compound semiconductor. 
     For example, the first conductive first semiconductor layer  11  may be realized by using a semiconductor material having a compositional formula of In x Al y Ga 1-x-y N (0≦x≦1, 0≦y≦1, 0≦x+y≦1). For example, the first conductive first semiconductor layer  11  may include one selected from the group consisting of GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP doped with N-type dopants such as Si, Ge, Sn, Se, and Te. 
     The active layer  12  emits light having a wavelength corresponding to the energy band gap difference according to materials constituting the active layer  13  through the combination of electrons (or holes) injected through the first conductive semiconductor layer  11  and holes (or electrons) injected through the second conductive semiconductor layer  13 . The active layer  12  may have one of a single quantum well (SQW) structure, a multi-quantum well (MQW) structure, a quantum dot structure, and a quantum wire structure, but the embodiment is not limited thereto. 
     The active layer  12  may be realized by using a compound semiconductor. The active layer  12  may be realized by using a semiconductor material having a compositional formula of In x Al y Ga 1-x-y N (0≦x≦1, 0≦y≦1, 0≦x+y≦1). When the active layer  12  has an MQW structure, the active layer  12  may be formed by stacking a plurality of well layers and a plurality of barrier layers. For example, the active layer  12  may have a cycle of InGaN well layer/GaN barrier layer. 
     For example, the second conductive semiconductor layer  13  may include a P-type semiconductor layer. The second conductive semiconductor layer  13  may be realized by using a compound semiconductor. For example, the second conductive semiconductor layer  13  may be realized by using a group II-VI compound semiconductor, or a group II-V compound semiconductor. 
     For example, the second conductive semiconductor layer  13  may be realized by using a semiconductor material having a compositional formula of In x Al y Ga 1-x-y N (0≦x≦1, 0≦y≦1, 0≦x+y≦1). For example, the second conductive semiconductor layer  13  may include one selected from the group consisting of GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP doped with P-type dopants such as Mg, Zn, Ca, Sr, and Ba. 
     Meanwhile, the first conductive semiconductor layer  11  may include a P-type semiconductor layer and the second conductive semiconductor layer  13  may include the N-type semiconductor layer. In addition, a semiconductor layer including an N-type or P-type semiconductor layer may be additionally provided under the second conductive semiconductor layer  13 . Accordingly, the first light-emitting structure  10  may have at least one of an NP junction structure, a PN junction structure, an NPN junction structure, or a PNP junction structure. In addition, impurities may be doped into the first conductive semiconductor layer  11  and the second conductive semiconductor layer  13  with uniform or non-uniform doping concentration. In other words, the first light-emitting structure  10  may have various structures, and the embodiment is not limited thereto. 
     In addition, a first conductive InGaN/GaN superlattice structure or InGaN/InGaN superlattice structure may be formed between the first conductive semiconductor layer  11  and the active layer  12 . In addition, a second conductive AlGaN layer may be formed between the second conductive semiconductor layer  13  and the active layer  13 . 
     The reflective electrode  17  may be disposed under the light-emitting structure  10 . An ohmic contact layer  15  may be further disposed between the light-emitting structure  10  and the reflective electrode  17 . A metal layer  50  may be disposed under the light-emitting structure  10  and around the ohmic contact layer  15 . The metal layer  50  may be disposed around a lower portion of the light-emitting structure  10 . The metal layer  50  may be disposed around the reflective electrode  17 . 
     A current blocking layer  30  may be disposed at a lower portion of the light-emitting structure  10 . The current blocking layer  30  can prevent current concentration and improve light extraction efficiency. For instance, the current blocking layer  30  can be formed through plasma processing, ion implantation or laser damage scheme. For example, the current blocking layer  30  can be formed by implanting oxygen ions into the second conductive semiconductor layer  13  through an implantation process. 
     For example, the ohmic contact layer  15  may include a transparent conductive oxide layer. For example, the ohmic contact layer  15  may include at least one selected from the group consisting of an ITO (Indium Tin Oxide), an IZO (Indium Zinc Oxide), an AZO (Aluminum Zinc Oxide), an AGZO (Aluminum Gallium Zinc Oxide), an IZTO (Indium Zinc Tin Oxide), an IAZO (Indium Aluminum Zinc Oxide), an IGZO (Indium Gallium Zinc Oxide), an IGTO (Indium Gallium Tin Oxide), an ATO (Antimony Tin Oxide), a GZO (Gallium Zinc Oxide), an IZON (IZO Nitride), ZnO, IrOx, RuOx, NiO, Pt and Ag. 
     The reflective electrode  17  may include a material having high reflectance. For example, the reflective electrode  17  may include a metal including at least one of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Cu, Au, and Hf, or an alloy thereof. In addition, the reflective electrode  17  may be formed in a multi-layer of the metal or the alloy thereof and a transmissive conductive material such as an ITO (Indium-Tin-Oxide), an IZO (Indium-Zinc-Oxide), an IZTO (Indium-Zinc-Tin-Oxide), an IAZO (Indium-Aluminum-Zinc-Oxide), an IGZO (Indium-Gallium-Zinc-Oxide), an IGTO (Indium-Gallium-Tin-Oxide), an AZO (Aluminum-Zinc-Oxide), or an ATO (Antimony-Tin-Oxide). For example, according to the embodiment, the reflective electrode  17  may include at least one of Ag, Al, an Ag—Pd—Cu alloy, and an Ag—Cu alloy. 
     The ohmic contact layer  15  may come into ohmic-contact with the light-emitting structure  10 . The reflective electrode  17  may reflect light incident thereto from the light-emitting structure  10  to increase the quantity of light extracted to an outside. 
     The metal layer  50  may include at least one of Cu, Ni, Ti, Ti—W, Cr, W, Pt, V, Fe, and Mo. The metal layer  50  may serve as a diffusion barrier layer. A bonding layer  60  and a support member  70  may be disposed under the metal layer  50 . 
     The metal layer  50  may prevent a material included in the bonding layer  60  from being diffused to the reflective electrode  17  in the process of providing the bonding layer  60 . The metal layer  50  may prevent a material, such as Sn, included in the bonding layer  60  from exerting an influence upon the reflective electrode  17 . 
     The bonding layer  60  may include barrier metal or bonding metal. For example, the bonding layer  60  may include at least one of Ti, Au, Sn, Ni, Cr, Ga, In, Bi, Cu, Ag, Nb, Pd and Ta. The support member  70  may support the light-emitting structure  10  according to the embodiment while performing a heat radiation function. The bonding layer  60  may be realized in the form of a seed layer. 
     The support member  70  may include at least one of semiconductor substrates (e.g., Si, Ge, GaN, GaAs, ZnO, SiC, and SiGe substrates) implanted with Ti, Cr, Ni, Al, Pt, Au, W, Cu, Mo, Cu—W, or impurities. For example, the support member  70  may be formed of insulating material. 
     Meanwhile, the light-emitting device according to the embodiment may include the electrode  80  which is a conductive ion implantation layer disposed in the first conductive semiconductor layer  11 . For instance, the electrode  80  can be formed by implanting metallic ions through an ion implantation process. The electrode  80  can be formed by implanting at least one material selected from Ti, Al and Si ions through an ion implantation process. 
     The electrode  80  may include metallic material. The electrode  80  may include at least metallic material selected from Ti, Al and Si ions. Incident light may transmit through the electrode  80 . Thus, light emitted from the light-emitting structure  10  may be transmitted to the outside without being absorbed in the electrode  80 , so that the light extraction efficiency can be improved. 
     The electrode  80  may be disposed in the first conductive semiconductor layer  11 . The electrode  80  may be formed with a depth in the range of 50 nm to 3000 nm. The electrode  80  may be spaced apart from the active layer  12 . The electrode  80  may be spaced apart from the active layer  12  by at least 100 nm. 
     The light-emitting device according to the embodiment may include a pad part  90  electrically connected to the electrode  80 . For instance, the pad part  90  may be formed on the first conductive semiconductor layer  11 . The pad part  90  may make contact with the electrode  80 . In addition, the pad part  90  may make contact with the first conductive semiconductor layer  11 . 
     The electrode  80  may include a plurality of wires disposed in the first conductive semiconductor layer  11 . In addition, the electrode  80  may include a connection wire disposed in the first conductive semiconductor layer  11  to electrically connect the wires to each other. 
     For instance, the electrode  80  and the pad part  90  may be configured as shown in  FIG. 2 . The electrode  80  may be disposed at an outer portion of the first conductive semiconductor layer  11  with a predetermined line width. In addition, the electrode  80  may be disposed at the center of the first conductive semiconductor layer  11  with a predetermined line width. However, the arrangement of the electrode  80  may not be limited above, but various modified. 
     The pad part  90  may be electrically connected to the electrode  80 . The pad part  90  may make contact with the electrode  80  or the first conductive semiconductor layer  11 . The pad part  90  may have an area smaller than a width of the electrode  80 . In addition, the pad part  90  may have an area larger than a width of the electrode  80 . 
     According to the embodiment, power may be applied to the light-emitting structure  10  through the reflective electrode  17  and the electrode  80 . According to the embodiment, the pad part  90  may be realized in the form of a multiple layer. The pad part  90  may include an ohmic layer, an intermediate layer, and an upper layer. The ohmic layer may include a material selected from the group consisting of Cr, V, W, Ti, and Zn to realize ohmic contact. The intermediate layer may be realized by using a material selected from the group consisting of Ni, Cu, and Al. For example, the upper layer may include Au. 
     A light extraction pattern may be provided on the top surface of the light-emitting structure  10 . A concavo-convex pattern may be provided on the top surface of the light-emitting structure  10 . For example, the light extraction pattern provided on the light-emitting structure  10  may be formed through a PEC (photo electro chemical) etching process. Therefore, according to the embodiment, the light extraction effect to the outside can be increased. 
     In addition, a light extraction pattern may be provided on the top surface of the electrode  80 . A concavo-convex pattern may be provided on the top surface of the electrode  80 . The electrode  80  may be formed of transparent material, so incident light may pass through the electrode  80 . The light emitted from the light-emitting structure  10  may be transmitted to the outside without being absorbed in the electrode  80 , so that the light extraction efficiency can be improved. 
     Hereinafter, a method of fabricating the light-emitting device according to the embodiment will be described with reference to  FIGS. 3 to 7 . 
     According to the method of fabricating the light-emitting device of the embodiment, as shown in  FIG. 3 , the first conductive semiconductor layer  11 , the active layer  12 , and the second conductive semiconductor layer  13  may be formed on a substrate  5 . The first conductive semiconductor layer  11 , the active layer  12 , and the second conductive semiconductor layer  13  may be defined as the light-emitting structure  10   
     For example, the substrate  5  may include at least one of a sapphire substrate (Al 2 O 3 ), SiC, GaAs, GaN, ZnO, Si, GaP, InP, and Ge, but the embodiment is not limited thereto. A buffer layer may be interposed between the first conductive semiconductor layer  11  and the substrate  5 . 
     For example, the first conductive semiconductor layer  11  may include an N-type semiconductor layer doped with N-type dopants serving as first conductive dopants, and the second conductive semiconductor layer  13  may include a P-type semiconductor layer doped with P-type dopants serving as second conductive dopants. In addition, the first conductive semiconductor layer  11  may include a P-type semiconductor layer, and the second conductive semiconductor layer  13  may include an N-type semiconductor layer. 
     For example, the first conductive semiconductor layer  11  may include an N-type semiconductor. The first conductive semiconductor layer  11  may include a semiconductor material having a compositional formula of In x Al y Ga 1-x-y N (0≦x≦1, 0≦y≦1, 0≦x+y≦1). For example, the first conductive semiconductor layer  11   a  may include one selected from the group consisting of InAlGaN, GaN, AlGaN, AlInN, InGaN, AlN, and InN, and may be doped with N-type dopants such as Si, Ge, Sn, Se, and Te. 
     The active layer  12  emits light having a wavelength corresponding to the energy band gap difference according to materials constituting the active layer  12  through the combination of electrons (or holes) injected through the first conductive semiconductor layer  11  and holes (or electrons) injected through the second conductive semiconductor layer  13 . The active layer  12  may have one of a single quantum well (SQW) structure, a multi-quantum well (MQW) structure, a quantum dot structure, and a quantum wire structure, but the embodiment is not limited thereto. 
     The active layer  12  may be realized by using a semiconductor material having a compositional formula of In x Al y Ga 1-x-y N (0≦x≦1, 0≦y≦1, 0≦x+y≦1). When the active layer  12  has an MQW structure, the active layer  12  may be formed by stacking a plurality of well layers and a plurality of barrier layers. For example, the active layer  12  may have a cycle of InGaN well layer/GaN barrier layer. 
     For example, the second conductive semiconductor layer  13  may be realized by using a P type semiconductor. The second conductive semiconductor layer  13  may be realized by using a semiconductor material having a compositional formula of In x Al y Ga 1-x-y N (0≦x≦1, 0≦y≦1, 0≦x+y≦1). For example, the second conductive semiconductor layer  13  may include one selected from the group consisting of InAlGaN, GaN, AlGaN, InGaN, AlInN, AlN, and InN, and may be doped with P-type dopants such as Mg, Zn, Ca, Sr, and Ba. 
     Meanwhile, the first conductive semiconductor layer  11  may include a P-type semiconductor layer and the second conductive semiconductor layer  13  may include the N-type semiconductor layer. In addition, a semiconductor layer including an N-type or P-type semiconductor layer may be additionally provided on the second conductive semiconductor layer  13 . Accordingly, the light-emitting structure  10  may have at least one of an NP junction structure, a PN junction structure, an NPN junction structure, or a PNP junction structure. In addition, impurities may be doped into the first conductive semiconductor layer  11  and the second conductive semiconductor layer  13  with uniform or non-uniform doping concentration. In other words, the light-emitting structure  10  may have various structures, and the embodiment is not limited thereto. 
     In addition, the first conductive InGaN/GaN superlattice structure or InGaN/InGaN superlattice structure may be formed between the first conductive semiconductor layer  11  and the active layer  12 . In addition, a second conductive AlGaN layer may be formed between the second conductive semiconductor layer  13  and the active layer  12 . 
     Next, as shown in  FIG. 4 , the current blocking layer  30  may be formed on the light-emitting structure  10 . The current blocking layer  30  may be formed on the second conductive semiconductor layer  13 . For instance, the current blocking layer  30  can be formed through plasma processing, ion implantation or laser damage scheme. For example, the current blocking layer  30  can be formed by implanting oxygen ions into the second conductive semiconductor layer  13  through an implantation process. 
     Then, as shown in  FIG. 5 , the ohmic contact layer  15  and the reflective electrode  17  may be formed on the light-emitting structure  10 . 
     For example, the ohmic contact layer  15  may include a transparent conductive oxide layer. For example, the ohmic contact layer  15  may include at least one selected from the group consisting of an ITO (Indium Tin Oxide), an IZO (Indium Zinc Oxide), an AZO (Aluminum Zinc Oxide), an AGZO (Aluminum Gallium Zinc Oxide), an IZTO (Indium Zinc Tin Oxide), an IAZO (Indium Aluminum Zinc Oxide), an IGZO (Indium Gallium Zinc Oxide), an IGTO (Indium Gallium Tin Oxide), an ATO (Antimony Tin Oxide), a GZO (Gallium Zinc Oxide), an IZON (IZO Nitride), ZnO, IrOx, RuOx, NiO, Pt and Ag. 
     The reflective electrode  17  may include a material having high reflectance. For example, the reflective electrode  17  may include a metal including at least one of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Cu, Au, and Hf, or an alloy thereof. In addition, the reflective electrode  17  may be formed in a multi-layer of the metal or the alloy thereof and a transmissive conductive material such as an ITO (Indium-Tin-Oxide), an IZO (Indium-Zinc-Oxide), an IZTO (Indium-Zinc-Tin-Oxide), an IAZO (Indium-Aluminum-Zinc-Oxide), an IGZO (Indium-Gallium-Zinc-Oxide), an IGTO (Indium-Gallium-Tin-Oxide), an AZO (Aluminum-Zinc-Oxide), or an ATO (Antimony-Tin-Oxide). For example, according to the embodiment, the reflective electrode  17  may include at least one of Ag, Al, an Ag—Pd—Cu alloy, and an Ag—Cu alloy. 
     In addition, as shown in  FIG. 5 , the metal layer  50  may be formed on the reflective layer  17 . The metal layer  50  may be formed around the ohmic contact layer  15  and on the reflective layer  17 . The metal layer  50  may include at least one of Cu, Ni, Ti, Ti—W, Cr, W, Pt, V, Fe, and Mo. The metal layer  50  may serve as a diffusion barrier layer. 
     Meanwhile, above processes for forming layers are illustrative purpose only and the process sequence may be variously changed. 
     Then, as shown in  FIG. 6 , the bonding layer  60  and the support member  70  may be provided on the metal layer  50 . The metal layer  50  may prevent a material included in the bonding layer  60  from being diffused to the reflective electrode  17  in the process of providing the bonding layer  60 . The metal layer  50  may prevent a material, such as Sn, included in the bonding layer  60  from exerting an influence upon the reflective electrode  17 . 
     The bonding layer  60  may include barrier metal or bonding metal. For example, the bonding layer  60  may include at least one of Ti, Au, Sn, Ni, Cr, Ga, In, Bi, Cu, Ag, Nb, Pd and Ta. The support member  70  may support the light-emitting structure  10  according to the embodiment while performing a heat radiation function. The bonding layer  60  may be realized in the form of a seed layer. 
     The support member  70  may include at least one of semiconductor substrates (e.g., Si, Ge, GaN, GaAs, ZnO, SiC, and SiGe substrates) implanted with Ti, Cr, Ni, Al, Pt, Au, W, Cu, Mo, Cu—W, or impurities. 
     Next, the substrate  5  is removed from the first conductive semiconductor layer  11 . According to one example, the substrate  5  may be removed through a laser lift off (LLO) process. The LLO process is a process to delaminate the substrate  5  from the first conductive semiconductor layer  11  by irradiating a laser to the bottom surface of the substrate  5 . 
     Then, as shown in  FIG. 7 , the lateral side of the light-emitting structure  10  is etched through an isolation etching process to expose a portion of the metal layer  30 . The isolation etching process may be performed through a dry etching process such as an inductively coupled plasma (ICP) process, but the embodiment is not limited thereto. 
     A first region of the metal layer  50  may be disposed under the light-emitting structure  10 . A second region of the metal layer  50  may extend outward from the first region. The second region of the metal layer  50  may horizontally extend from the first region. The second region of the metal layer  50  may be exposed to a lower outer peripheral portion of the light-emitting structure  10 . 
     A light extraction pattern may be provided on the top surface of the light-emitting structure  10 . A concavo-convex pattern may be provided on the top surface of the light-emitting structure  10 . For example, the light extraction pattern may be formed through a PEC (photo electro chemical) etching process. Therefore, according to the embodiment, the light extraction effect to the outside can be increased. According to the embodiment, the top surface of the light-emitting structure  10  may serve as an N plane, which has a higher roughness than a Ga plane, so the light extraction efficiency may be further improved. 
     Meanwhile, the light-emitting device according to the embodiment may include the electrode  80  which is a conductive ion implantation layer disposed in the first conductive semiconductor layer  11 . For instance, the electrode  80  can be formed by implanting metallic ions through an ion implantation process. The electrode  80  can be formed by implanting at least one material selected from Ti, Al and Si ions through an ion implantation process. 
     The electrode  80  may include metallic material. The electrode  80  may include at least metallic material selected from Ti, Al and Si ions. Incident light may transmit through the electrode  80 . Thus, light emitted from the light-emitting structure  10  may be transmitted to the outside without being absorbed in the electrode  80 , so that the light extraction efficiency can be improved. 
     The electrode  80  may be disposed in the first conductive semiconductor layer  11 . The electrode  80  may be formed with a depth in the range of 50 nm to 3000 nm. The electrode  80  may be spaced apart from the active layer  12 . The electrode  80  may be spaced apart from the active layer  12  by at least 100 nm. 
     The light-emitting device according to the embodiment may include the pad part  90  electrically connected to the electrode  80 . For instance, the pad part  90  may be formed on the first conductive semiconductor layer  11 . The pad part  90  may make contact with the electrode  80 . In addition, the pad part  90  may make contact with the first conductive semiconductor layer  11 . 
     The electrode  80  may include a plurality of wires disposed in the first conductive semiconductor layer  11 . In addition, the electrode  80  may include a connection wire disposed in the first conductive semiconductor layer  11  to electrically connect the wires to each other. 
     For instance, the electrode  80  and the pad part  90  may be configured as shown in  FIG. 2 . The electrode  80  may be disposed at an outer portion of the first conductive semiconductor layer  11  with a predetermined line width. In addition, the electrode  80  may be disposed at the center of the first conductive semiconductor layer  11  with a predetermined line width. However, the arrangement of the electrode  80  may not be limited above, but various modified. 
     The pad part  90  may be electrically connected to the electrode  80 . The pad part  90  may make contact with the electrode  80  or the first conductive semiconductor layer  11 . The pad part  90  may have an area smaller than a width of the electrode  80 . In addition, the pad part  90  may have an area larger than a width of the electrode  80 . 
     According to the embodiment, power may be applied to the light-emitting structure  10  through the reflective electrode  17  and the electrode  80 . According to the embodiment, the pad part  90  may be realized in the form of a multiple layer. The pad part  90  may include an ohmic layer, an intermediate layer, and an upper layer. The ohmic layer may include a material selected from the group consisting of Cr, V, W, Ti, and Zn to realize ohmic contact. The intermediate layer may be realized by using a material selected from the group consisting of Ni, Cu, and Al. For example, the upper layer may include Au. 
     In addition, a light extraction pattern may be provided on the top surface of the electrode  80 . A concavo-convex pattern may be provided on the top surface of the electrode  80 . The electrode  80  may be formed of transparent material, so incident light may pass through the electrode  80 . The light emitted from the light-emitting structure  10  may be transmitted to the outside without being absorbed in the electrode  80 , so that the light extraction efficiency can be improved. 
       FIG. 8  is a view showing another example of a light-emitting device according to the embodiment. In the following description about the light-emitting device shown in  FIG. 8 , components and structures the same as those described with reference to  FIG. 1  will not be further described in order to avoid redundancy. 
     The light-emitting device according to the embodiment shown in  FIG. 8  may not include the current blocking layer as compared with the light-emitting device shown in  FIG. 1 . Thus, the metal layer  50  may be disposed around a lower portion of the light-emitting structure  10 . A first region of the metal layer  50  may be disposed under the light-emitting structure  10 . The first region of the metal layer  50  may make contact with the lower portion of the light-emitting structure  10 . A second region of the metal layer  50  may extend outward from the first region. The second region of the metal layer  50  may horizontally extend from the first region. The second region of the metal layer  50  may be exposed to a lower outer peripheral portion of the light-emitting structure  10 . 
     The light-emitting device according to the embodiment may include the electrode  80  which is a conductive ion implantation layer disposed in the first conductive semiconductor layer  11 . For instance, the electrode  80  can be formed by implanting metallic ions through an ion implantation process. The electrode  80  can be formed by implanting at least one material selected from Ti, Al and Si ions through an ion implantation process. 
     The electrode  80  may include metallic material. The electrode  80  may include at least metallic material selected from Ti, Al and Si ions. Incident light may transmit through the electrode  80 . Thus, light emitted from the light-emitting structure  10  may be transmitted to the outside without being absorbed in the electrode  80 , so that the light extraction efficiency can be improved. 
     The electrode  80  may be disposed in the first conductive semiconductor layer  11 . The electrode  80  may be formed with a depth in the range of 50 nm to 3000 nm. The electrode  80  may be spaced apart from the active layer  12 . The electrode  80  may be spaced apart from the active layer  12  by at least 100 nm. 
     The light-emitting device according to the embodiment may include the pad part  90  electrically connected to the electrode  80 . For instance, the pad part  90  may be formed on the first conductive semiconductor layer  11 . The pad part  90  may make contact with the electrode  80 . In addition, the pad part  90  may make contact with the first conductive semiconductor layer  11 . 
     The electrode  80  may include a plurality of wires disposed in the first conductive semiconductor layer  11 . In addition, the electrode  80  may include a connection wire disposed in the first conductive semiconductor layer  11  to electrically connect the wires to each other. 
     For instance, the electrode  80  and the pad part  90  may be configured as shown in  FIG. 2 . The electrode  80  may be disposed at an outer portion of the first conductive semiconductor layer  11  with a predetermined line width. In addition, the electrode  80  may be disposed at the center of the first conductive semiconductor layer  11  with a predetermined line width. However, the arrangement of the electrode  80  may not be limited above, but various modified. 
     The pad part  90  may be electrically connected to the electrode  80 . The pad part  90  may make contact with the electrode  80  or the first conductive semiconductor layer  11 . The pad part  90  may have an area smaller than a width of the electrode  80 . In addition, the pad part  90  may have an area larger than a width of the electrode  80 . 
     According to the embodiment, power may be applied to the light-emitting structure  10  through the reflective electrode  17  and the electrode  80 . According to the embodiment, the pad part  90  may be realized in the form of a multiple layer. The pad part  90  may include an ohmic layer, an intermediate layer, and an upper layer. The ohmic layer may include a material selected from the group consisting of Cr, V, W, Ti, and Zn to realize ohmic contact. The intermediate layer may be realized by using a material selected from the group consisting of Ni, Cu, and Al. For example, the upper layer may include Au. 
     A light extraction pattern may be provided on the top surface of the light-emitting structure  10 . A concavo-convex pattern may be provided on the top surface of the light-emitting structure  10 . For example, the light extraction pattern provided on the light-emitting structure  10  may be formed through a PEC (photo electro chemical) etching process. Therefore, according to the embodiment, the light extraction effect to the outside can be increased. 
     In addition, a light extraction pattern may be provided on the top surface of the electrode  80 . A concavo-convex pattern may be provided on the top surface of the electrode  80 . The electrode  80  may be formed of transparent material, so incident light may pass through the electrode  80 . The light emitted from the light-emitting structure  10  may be transmitted to the outside without being absorbed in the electrode  80 , so that the light extraction efficiency can be improved. 
       FIG. 9  is a view showing another example of a light-emitting device according to the embodiment. In the following description about the light-emitting device shown in  FIG. 9 , components and structures the same as those described with reference to  FIG. 1  will not be further described in order to avoid redundancy. 
     The light-emitting device according to the embodiment may include the electrode  80  which is a conductive ion implantation layer disposed in the first conductive semiconductor layer  11 . For instance, the electrode  80  can be formed by implanting metallic ions through an ion implantation process. The electrode  80  can be formed by implanting at least one material selected from Ti, Al and Si ions through an ion implantation process. 
     The electrode  80  may include metallic material. The electrode  80  may include at least metallic material selected from Ti, Al and Si ions. Incident light may transmit through the electrode  80 . Thus, light emitted from the light-emitting structure  10  may be transmitted to the outside without being absorbed in the electrode  80 , so that the light extraction efficiency can be improved. 
     The electrode  80  may be disposed in the first conductive semiconductor layer  11 . The electrode  80  may be formed with a depth in the range of 50 nm to 3000 nm. The electrode  80  may be spaced apart from the active layer  12 . The electrode  80  may be spaced apart from the active layer  12  by at least 100 nm. 
     The light-emitting device according to the embodiment may include the pad part  90  electrically connected to the electrode  80 . For instance, the pad part  90  may be formed on the first conductive semiconductor layer  11 . The pad part  90  may make contact with the electrode  80 . In addition, the pad part  90  may make contact with the first conductive semiconductor layer  11 . 
     The electrode  80  may include a plurality of wires disposed in the first conductive semiconductor layer  11 . In addition, the electrode  80  may include a connection wire disposed in the first conductive semiconductor layer  11  to electrically connect the wires to each other. In this case, the formation depth of the wires and the connection wire that constitute the electrode  80  may be adjusted by controlling the energy during the ion implantation process. 
     The pad part  90  may be electrically connected to the electrode  80 . The pad part  90  may make contact with the electrode  80  or the first conductive semiconductor layer  11 . The pad part  90  may have an area smaller than a width of the electrode  80 . In addition, the pad part  90  may have an area larger than a width of the electrode  80 . 
     According to the embodiment, power may be applied to the light-emitting structure  10  through the reflective electrode  17  and the electrode  80 . According to the embodiment, the pad part  90  may be realized in the form of a multiple layer. The pad part  90  may include an ohmic layer, an intermediate layer, and an upper layer. The ohmic layer may include a material selected from the group consisting of Cr, V, W, Ti, and Zn to realize ohmic contact. The intermediate layer may be realized by using a material selected from the group consisting of Ni, Cu, and Al. For example, the upper layer may include Au. 
     A light extraction pattern may be provided on the top surface of the light-emitting structure  10 . A concavo-convex pattern may be provided on the top surface of the light-emitting structure  10 . For example, the light extraction pattern provided on the light-emitting structure  10  may be formed through a PEC (photo electro chemical) etching process. Therefore, according to the embodiment, the light extraction effect to the outside can be increased. 
     In addition, a light extraction pattern may be provided on the top surface of the electrode  80 . A concavo-convex pattern may be provided on the top surface of the electrode  80 . The electrode  80  may be formed of transparent material, so incident light may pass through the electrode  80 . The light emitted from the light-emitting structure  10  may be transmitted to the outside without being absorbed in the electrode  80 , so that the light extraction efficiency can be improved. 
       FIG. 10  is a view showing a light-emitting device package to which the light-emitting device according to the embodiment is applied. 
     Referring to  FIG. 10 , the light-emitting device package according to the embodiment may include a body  120 , first and second lead electrodes  131  and  132  formed on the body  120 , a light-emitting device  100  provided on the body  120  and electrically connected to the first and second lead electrodes  131  and  132  and a molding member  140  that surrounds the light-emitting device  100 . 
     The body  120  may include silicon, synthetic resin or metallic material, and an inclined surface may be formed in the vicinity of the light-emitting device  100 . 
     The first and second lead electrodes  131  and  132  are electrically isolated from each other to supply power to the light-emitting device  100 . The first and second lead electrode  131  and  132  can improve the light efficiency by reflecting the light emitted from the light-emitting device  100 . Further, the first and second lead electrodes  131  and  132  may dissipate heat generated from the light-emitting device  100  to the outside. 
     The light-emitting device  100  can be installed on the body  120  or the first or second lead electrode  131  or  132 . 
     The light-emitting device  100  may be electrically connected to the first and second lead electrodes  131  and  132  through one of a wire scheme, a flip-chip scheme, and a die-bonding scheme. 
     The molding member  140  may surround the light-emitting device  100  to protect the light-emitting device  100 . In addition, the molding member  140  may include phosphors to change the wavelength of the light emitted from the light-emitting device  100 . 
     A plurality of light-emitting device or light-emitting device packages according to the embodiment may be arrayed on a substrate, and an optical member including a lens, a light guide plate, a prism sheet, or a diffusion sheet may be provided on the optical path of the light emitted from the light-emitting device package. The light-emitting device package, the substrate, and the optical member may serve as a light unit. The light unit is realized in a top view type or a side view type and variously provided in display devices of a portable terminal and a laptop computer or a lighting apparatus and an indicator apparatus. In addition, a lighting apparatus according to another embodiment can include a light-emitting device, or a light-emitting device package according to the embodiment. For example, the lighting apparatus may include a lamp, a signal lamp, an electric sign board and a headlight of a vehicle. 
     The light-emitting device according to the embodiment may be applied to the light unit. The light unit has a structure in which a plurality of light-emitting devices are arrayed. The light unit may include a display device as shown in  FIGS. 11 and 12  and the lighting apparatus as shown in  FIGS. 13 to 17 . 
     Referring to  FIG. 11 , a display device  1000  according to the embodiment includes a light guide plate  1041 , a light-emitting module  1031  for supplying the light to the light guide plate  1041 , a reflective member  1022  provided below the light guide plate  1041 , an optical sheet  1051  provided above the light guide plate  1041 , a display panel  1061  provided above the optical sheet  1051 , and a bottom cover  1011  for receiving the light guide plate  1041 , the light-emitting module  1031 , and the reflective member  1022 . However, the embodiment is not limited to the above structure. 
     The bottom cover  1011 , the reflective member  1022 , the light guide plate  1041  and the optical sheet  1051  may constitute a light unit  1050 . 
     The light guide plate  1041  diffuses the light to provide surface light. The light guide plate  1041  may include transparent material. For example, the light guide plate  1041  may include one of acryl-based resin, such as PMMA (polymethyl methacrylate), PET (polyethylene terephthalate), PC (polycarbonate), COC (cyclic olefin copolymer) and PEN (polyethylene naphthalate) resin. 
     The light-emitting module  1031  supplies the light to at least one side of the light guide plate  1041 . The light-emitting module  1031  serves as the light source of the display device. 
     At least one light-emitting module  1031  is provided to directly or indirectly supply the light from one side of the light guide plate  1041 . The light-emitting module  1031  may include a substrate  1033  and light-emitting devices  100  or the light-emitting device package  200  according to the embodiment described above. The light-emitting packages  200  may be arrayed on the substrate  1033  while being spaced apart from each other at the predetermined interval. 
     The substrate  1033  may be a printed circuit board (PCB) including a circuit pattern. In addition, the substrate  1033  may also include a metal core PCB (MCPCB) or a flexible PCB (FPCB) as well as the PCB, but the embodiment is not limited thereto. If the light-emitting device packages  200  are installed on the lateral side of the bottom cover  1011  or on a heat dissipation plate, the substrate  1033  may be omitted. The heat dissipation plate may partially make contact with the top surface of the bottom cover  1011 . 
     In addition, the light-emitting device packages  200  are installed such that light exit surfaces of the light-emitting device packages  200  are spaced apart from the light guide plate  1041  at a predetermined distance, but the embodiment is not limited thereto. The light-emitting device packages  200  may directly or indirectly supply the light to a light incident part, which is one side of the light guide plate  1041 , but the embodiment is not limited thereto. 
     The reflective member  1022  may be disposed below the light guide plate  1041 . The reflective member  1022  reflects the light, which travels downward through the bottom surface of the light guide plate  1041 , upward, thereby improving the brightness of the light unit  1050 . For example, the reflective member  1022  may include PET, PC or PVC resin, but the embodiment is not limited thereto. The reflective member  1022  may serve as the top surface of the bottom cover  1011 , but the embodiment 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  therein. To this end, the bottom cover  1011  has a receiving section  1012  having a box shape with an opened top surface, but the embodiment is not limited thereto. The bottom cover  1011  can be coupled with the top cover (not shown), but the embodiment is not limited thereto. 
     The bottom cover  1011  can be manufactured through a press process or an extrusion process by using metallic material or resin material. In addition, the bottom cover  1011  may include metal or non-metallic material having superior thermal conductivity, but the embodiment is not limited thereto. 
     The display panel  1061 , for example, is an LCD panel including first and second transparent substrates, which are opposite to each other, and a liquid crystal layer interposed between the first and second substrates. A polarizing plate can be attached to at least one surface of the display panel  1061 , but the embodiment is not limited thereto. The display panel  1061  displays information by using light passing through the optical sheet  1051 . The display device  1000  can be applied to various portable terminals, monitors of notebook computers and laptop computers, and televisions. 
     The optical sheet  1051  is disposed between the display panel  1061  and the light guide plate  1041  and includes at least one transmissive sheet. For example, the optical sheet  1051  includes at least one of a diffusion sheet, horizontal and vertical prism sheets, and a brightness enhanced sheet. The diffusion sheet diffuses the incident light, the horizontal and/or vertical prism sheet concentrates the incident light onto a display region, and the brightness enhanced sheet improves the brightness by reusing the light to be lost. In addition, a protective sheet can be provided on the display panel  1061 , but the embodiment is not limited thereto. 
     The light guide plate  1041  and the optical sheet  1051  can be provided on the optical path of the light-emitting module  1031  as optical members, but the embodiment is not limited thereto. 
       FIG. 12  is a view showing another example of a display device according to the embodiment. 
     Referring to  FIG. 12 , the display device  1100  includes a bottom cover  1152 , a substrate  1020  on which the light-emitting devices  100  are arrayed, an optical member  1154 , and a display panel  1155 . 
     The substrate  1020  and the light-emitting device packages  200  may constitute a light-emitting module  1060 . The bottom cover  1152 , at least one light-emitting module  1060 , and the optical member  154  may constitute a light unit. 
     The bottom cover  1152  can be provided therein with a receiving section  1153 , but the embodiment is not limited thereto. 
     In this case, 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 brightness enhanced sheet. The light guide plate may include PC or PMMA (Poly methyl methacrylate). The light guide plate can be omitted. The diffusion sheet diffuses the incident light, the horizontal and vertical prism sheets concentrate the incident light onto a display region, and the brightness enhanced sheet improves the brightness by reusing the light to be lost. 
     The optical member  1154  is disposed above the light-emitting module  1060  in order to convert the light emitted from the light-emitting module  1060  into the surface light. In addition, the optical member  1154  may diffuse or collect the light. 
       FIGS. 13 to 15  are views showing a lighting apparatus according to the embodiment. 
       FIG. 13  is a top perspective view of the lighting apparatus,  FIG. 14  is a bottom perspective view of the lighting apparatus shown in  FIG. 13  and  FIG. 15  is an exploded perspective view of the lighting apparatus shown in  FIG. 13 . 
     Referring to  FIGS. 13 to 15 , the lighting apparatus according to the embodiment may include a cover  2100 , a light source module  2200 , a radiator  2400 , a power supply part  2600 , an inner case  2700 , and a socket  2800 . The lighting apparatus according to the embodiment may further include at least one of a member  2300  and a holder  2500 . The light source module  2200  may include the light-emitting device package according to the embodiment. 
     For example, the cover  2100  may have a bulb shape or a hemispheric shape. The cover  2100  may have a hollow structure which is partially open. The cover  2100  may be optically coupled with the light source module  2200 . For example, the cover  2100  may diffuse, scatter, or excite light provided from the light source module  2200 . The cover  2100  may be an optical member. The cover  2100  may be coupled with the radiator  2400 . The cover  2100  may include a coupling part which is coupled with the radiator  2400 . 
     The cover  2100  may include an inner surface coated with a milk-white pigment. The milk-white pigment may include a diffusion material to diffuse light. The roughness of the inner surface of the cover  2100  may be greater than the roughness of the outer surface of the cover  2100 . The surface roughness is provided for the purpose of sufficiently scattering and diffusing the light from the light source module  2200 . 
     The cover  2100  may include glass, plastic, polypropylene (PP), polyethylene (PE) or polycarbonate (PC). The polycarbonate (PC) has the superior light resistance, heat resistance and strength among the above materials. The cover  2100  may be transparent so that a user may view the light source module  2200  from the outside, or may be opaque. The cover  2100  may be formed through a blow molding scheme. 
     The light source module  220  may be disposed at one surface of the radiator  2400 . Accordingly, the heat from the light source module  220  is transferred to the radiator  2400 . The light source module  2200  may include a light source  2210 , a connection plate  2230 , and a connector  2250 . 
     The member  2300  is disposed on a top surface of the radiator  2400 , and includes guide grooves  2310  into which a plurality of light sources  2210  and the connector  2250  are inserted. The guide grooves  2310  correspond to a substrate of the light source  2210  and the connector  2250 . 
     A surface of the member  2300  may be coated with a light reflective material. For example, the surface of the member  2300  may be coated with white pigment. The member  2300  reflects again light, which is reflected by the inner surface of the cover  2100  and is returned to the direction of the light source module  2200 , to the direction of the cover  2100 . Accordingly, the light efficiency of the lighting apparatus according to the embodiment may be improved. 
     For example, the member  2300  may include an insulating material. The connection plate  2230  of the light source module  2200  may include an electrically conductive material. Accordingly, the radiator  2400  may be electrically connected to the connection plate  2230 . The member  2300  may be formed by an insulating material, thereby preventing the connection plate  2230  from being electrically shorted with the radiator  2400 . The radiator  2400  receives heat from the light source module  2200  and the power supply part  2600  and dissipates the heat. 
     The holder  2500  covers a receiving groove  2719  of an insulating part  2710  of an inner case  2700 . Accordingly, the power supply part  2600  received in the insulating part  2710  of the inner case  2700  is sealed. The holder  2500  includes a guide protrusion  2510 . The guide protrusion  2510  has a hole and a protrusion of the power supply part  2600  extends by passing through the hole. 
     The power supply part  2600  processes or converts an electric signal received from the outside and provides the processed or converted electric signal to the light source module  2200 . The power supply part  2600  is received in the receiving groove  2719  of the inner case  2700 , and is sealed inside the inner case  2700  by the holder  2500 . 
     The power supply part  2600  may include a protrusion  2610 , a guide part  2630 , a base  2650 , and an extension part  2670 . 
     The guide part  2630  has a shape protruding from one side of the base  2650  to the outside. The guide part  2630  may be inserted into the holder  2500 . A plurality of components may be disposed on one surface of the base  2650 . For example, the components may include a DC converter to convert AC power provided from an external power supply into DC power, a driving chip to control the driving of the light source module  2200 , and an electrostatic discharge (ESD) protection device to protect the light source module  2200 , but the embodiment is not limited thereto. 
     The extension part  2670  has a shape protruding from an opposite side of the base  2650  to the outside. The extension part  2670  is inserted into an inside of the connection part  2750  of the inner case  2700 , and receives an electric signal from the outside. For example, a width of the extension part  2670  may be smaller than or equal to a width of the connection part  2750  of the inner case  2700 . First terminals of a “+ electric wire” and a “− electric wire” are electrically connected to the extension part  2670  and second terminals of the “+ electric wire” and the “− electric wire” may be electrically connected to a socket  2800 . 
     The inner case  2700  may include a molding part therein together with the power supply part  2600 . The molding part is prepared by hardening molding liquid, and the power supply part  2600  may be fixed inside the inner case  2700  by the molding part. 
       FIGS. 16 and 17  are views showing another example of a lighting apparatus according to the embodiment. 
       FIG. 16  is a perspective view of the lighting apparatus according to the embodiment and  FIG. 17  is an exploded perspective view of the lighting apparatus shown in  FIG. 16 . In the following description about the lighting apparatus shown in  FIGS. 16 and 17 , components and structures the same as those described with reference to  FIGS. 13 to 15  will not be further described in order to avoid redundancy. 
     Referring to  FIGS. 16 and 17 , the lighting apparatus according to the embodiment may include a cover  3100 , a light source part  3200 , a radiator  3300 , a circuit part  3400 , an inner case  3500 , and a socket  3600 . The light source part  3200  may include the light-emitting device or the light-emitting device module according to the embodiment. 
     The cover  3100  may have a hollow bulb shape. The cover  3100  has an opening  3110 . The light source part  3200  and a member  3350  may be inserted through the opening  3110 . 
     The cover  3100  may be coupled with the radiator  3300  and may surround the light source part  3200  and the member  3350 . The light source part  3200  and the member  3350  may be blocked from the outside by the coupling between the cover  3100  and the radiator  3300 . The cover  3100  may be coupled with the radiator  3300  by an adhesive or various schemes such as a rotation coupling scheme and a hook coupling scheme. The rotation coupling scheme is a scheme where a thread of the cover  3100  is coupled with a screw groove of the radiator  3300 , and the cover  3100  is coupled with the radiator  3300  by rotation of the cover  3100 . The hook coupling scheme is a scheme where a projection of the cover  3100  is inserted into a groove of the radiator  3300  so that the cover  3100  is coupled with the radiator  3300 . 
     The light source part  3200  is disposed at the member  3350  of the radiator  3300 , and a plurality of light source parts  3200  may be provided. In detail, the light source part  3200  may be disposed on at least one of side surfaces of the member  3350 . In addition, the light source part  3200  may be disposed at an upper portion of the side surface of the member  3350 . 
     Referring to  FIG. 17 , the light source part  3200  may be disposed at three of six side surfaces of the member  3350 . However, the embodiment is not limited thereto, and the light source part  3200  may be disposed at all side surfaces of the member  3350 . The light source part  3200  may include a substrate  3210  and a light-emitting device  3230 . The light-emitting device  3230  may be disposed on one surface of the substrate  3210 . 
     The substrate  3210  has a rectangular plate shape, but the embodiment is not limited thereto. The substrate  3210  may have various shapes. For example, the substrate  3210  may have a circular plate shape or a polygonal plate shape. The substrate  3210  may be provided by printing a circuit pattern on an insulator. For example, the substrate  3210  may include a typical printed circuit board (PCB), a metal core PCB, a flexible PCB, and a ceramic PCB. In addition, the substrate may have a COB (chips on board) type in which LED chips, which are not packaged, are directly bonded on the PCB. In addition, the substrate  3210  may include a material suitable to reflect light, or the surface of the substrate may have a color such as a white color or a silver color to effectively reflect the light. The substrate  3210  may be electrically connected to the circuit part  3400  received in the radiator  3300 . For example, the substrate  3210  and the circuit part  3400  may be connected to each other by a wire. The wire may connect the substrate  3210  and the circuit part  3400  to each other by passing through the radiator  3300 . 
     The light-emitting device  3230  may include a luminescence material. The luminescence material may include at least one of garnet-based phosphors (YAG, or TAG), silicate-based phosphors, nitride-based phosphors, and oxynitride-based phosphors. The luminescence material may include at least one of a red luminescence material, a yellow luminescence material and a green luminescence material. 
     The radiator  3300  is coupled with the cover  3100 , and may radiate heat from the light source part  3200 . The radiator  330  has a predetermined volume, and includes a top surface  3310  and a side surface  3330 . The member  3350  may be disposed on the top surface  3310  of the radiator  3310 . The top surface  3310  of the radiator  3300  may be coupled with the cover  3100 . The top surface  3310  of the radiator  3300  may have a shape corresponding to an opening  3110  of the cover  3100 . 
     A plurality of heat radiation pins  3370  may be disposed at the side surface  3330  of the radiator  3300 . The heat radiation pin  3370  may extend outward from the side surface  3330  of the radiator  3300  or may be connected to the side surface  3330  of the radiator  3300 . The heat radiation pin  3370  may improve heat radiation efficiency by increasing a heat radiation area of the radiator  3300 . The side surface  3330  may not include the heat radiation pin  3370 . 
     The member  3350  may be disposed on the top surface of the radiator  3300 . The member  3350  may be integrated with or coupled to the top surface  3310  of the radiator  3300 . The member  3350  may have the shape of a polygonal prism. In detail, the member  3350  may have the shape of a hexahedral prism. The member  3350  having the shape of a hexahedral prism includes a top surface, a bottom surface, and six side surfaces. The member  3350  may have the shape of a circular prism or the shape of an elliptical prism as well as the shape of a hexahedral prism. When the member  3350  has the shape of a circular prism or the shape of an elliptical prism, the substrate  3210  of the light source part  3200  may be a flexible substrate. 
     The light source part  3200  may be disposed at six side surfaces of the member  3350 . The light source part  3200  may be disposed at all or some of the six side surfaces of the member  3350 . The light source part  3200  is disposed at three of the six side surfaces of the member  3350 . 
     The substrate  3210  is disposed at the side surface of the member  3350 . The side surface of the member  3350  may be substantially vertical to the top surface  3310  of the radiator  3300 . Accordingly, the substrate  3210  and the top surface of the radiator  3300  may be substantially vertical to each other. 
     The member  3350  may include a material representing thermal conductivity. Thus, heat from the light source part  3200  can be rapidly transferred to the member  3350 . For example, the material for the member  3350  may include an alloy of metals such as aluminum (Al), nickel (Ni), copper (Cu), magnesium (Mg), silver (Ag), or tin (Sn). In addition, the member  3350  may include a plastic material having thermal conductivity. The plastic material having thermal conductivity is advantageous in that it is lighter than the metal and has thermal conductivity in a single direction. 
     The circuit part  3400  receives power from the outside, and converts the received power suitably for the light source part  3200 . The circuit part  3400  provides the converted power to the light source part  3200 . The circuit part  3400  may be disposed at the radiator  3300 . In detail, the circuit part  3400  may be received in the inner case  3500 , and may be received in the radiator  3300  together with the inner case  3500 . The circuit part  3400  may include a circuit board  3410  and a plurality of components mounted on the circuit board  3410 . 
     The circuit board  3410  has a circular shape, but the embodiment is not limited thereto. That is, the circuit board  3410  may have various shapes. For example, the circuit board may have an elliptical shape or a polygonal shape. The circuit board  3410  may be provided by printing a circuit pattern on an insulator. The circuit board  3410  is electrically connected to the substrate  3210  of the light source part  3200 . For example, the circuit part  3410  and the substrate  3210  may be connected to each other by a wire. The wire may be disposed inside the radiator  3300  to connect the substrate  3210  to the circuit board  3410 . For example, a plurality of components  3430  may include a direct current converter converting AC power provided from an external power supply into DC power, a driving chip controlling driving of the light source part  3200 , and an electrostatic discharge (ESD) protective device. 
     The inner case  3500  receives the circuit part  3400  therein. The inner case  3500  may include a receiving part  3510  to receive the circuit part  3400 . For example, the receiving part  3510  may have a cylindrical shape. The shape of the receiving part  3510  may be changed according to the shape of the radiator  3300 . The inner case  3500  may be received in the radiator  3300 . The receiving part  3510  of the inner case  3500  may be received in a receiving part which is formed at a bottom surface of the radiator  3300 . 
     The inner case  3500  may be coupled with the socket  3600 . The inner case  3500  may include a connecting part  3530  coupled with the socket  3600 . The connecting part  3530  may have a thread structure corresponding to a screw groove structure of the socket  3600 . The inner case  3500  is an insulator. Accordingly, the inner case  3500  prevents electric short between the circuit part  3400  and the radiator  3300 . For example, the inner case  3500  may include a plastic or resin material. 
     The socket  3600  may be coupled with the inner case  3500 . In detail, the socket  3600  may be coupled with the connecting part  3530  of the inner case  3500 . The socket  3600  may have the structure the same as that of a conventional incandescent light bulb. The socket  3600  is electrically connected to the circuit part  3400 . For example, the circuit part  3400  and the socket  3600  may be connected to each other by a wire. If external power is applied to the socket  3600 , the external power may be transferred to the circuit part  3400 . The socket  3600  may have a screw groove structure corresponding to a thread structure of the connecting part  3550 . 
     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.