KR20160085069A - Light emitting device and light emitting device package - Google Patents

Abstract

An embodiment relates to a light emitting device and a light emitting device package. The light emitting device of the embodiment includes a light emitting structure which includes a first conductivity type semiconductor layer, an active layer located on the first conductivity type semiconductor layer, and a second conductivity type semiconductor layer, a second electrode pad which is located in the first region of the first conductivity type semiconductor layer, a second electrode pad located on the second conductivity type semiconductor layer, and a current blocking layer which is located in the second region of the first conductivity type semiconductor layer and is overlapped with a second electrode pad. The current blocking layer touches the first conductivity type semiconductor layer exposed by removing the active layer and prevents optical loss due to the light absorption of the active layer. So, light efficiency can be improved.

Description

[0001] LIGHT EMITTING DEVICE AND LIGHT EMITTING DEVICE PACKAGE [0002]

Embodiments relate to a light emitting device and a light emitting device package.

Light Emitting Device is a pn junction diode whose electrical energy is converted into light energy. It can be produced from compound semiconductor such as group III and group V on the periodic table and by controlling the composition ratio of compound semiconductor, It is possible.

GaN-based light emitting devices (LEDs) are used in various applications such as color LED display devices, LED traffic signals, and white LEDs. In recent years, the luminous efficiency of a high-efficiency white LED is superior to the efficiency of a conventional fluorescent lamp, and is expected to replace fluorescent lamps in general illumination fields.

Among the conventional light emitting devices, a horizontal type light emitting device forms a nitride semiconductor layer on a substrate, and an electrode layer is located on the upper side of the nitride semiconductor layer.

Meanwhile, in the conventional light emitting device, a current blocking layer is formed between the electrode layer and the semiconductor layer in order to solve the current dispersion problem, and a technique for preventing the current from concentrating around the electrode pad located on the electrode layer is being studied.

However, in the conventional light emitting device, there is a problem that the light extraction efficiency is lowered due to the light absorption by which the emitted light re-enters the active layer located around the current blocking layer.

Embodiments provide a light emitting device and a light emitting device package for improving light extraction efficiency.

Embodiments provide a light emitting device and a light emitting device package that substantially obviate a region where light is absorbed by removing an active layer.

Embodiments provide a light emitting device and a light emitting device package capable of improving light extraction without further processing by forming a current blocking layer on the exposed first conductive semiconductor layer by removing an active layer in a mesa etching process.

A light emitting device according to an embodiment includes: a first conductive semiconductor layer; An active layer disposed on the first conductive semiconductor layer; And a second conductive semiconductor layer disposed on the active layer; A first electrode pad located in a first region of the first conductivity type semiconductor layer; A second electrode pad disposed on the second conductive semiconductor layer; And a current blocking layer located in a second region of the first conductivity type semiconductor layer and overlapped with the second electrode pad, wherein the current blocking layer is formed on the first conductive type semiconductor layer exposed by removing the active layer, Can be contacted.

A light emitting device according to another embodiment includes: a first conductive semiconductor layer; An active layer disposed on the first conductive semiconductor layer; And a second conductive semiconductor layer disposed on the active layer; A first electrode pad located in a first region of the first conductivity type semiconductor layer; A second electrode pad disposed on the second conductive semiconductor layer; And a current blocking layer located in a second region of the first conductive semiconductor layer and overlapped with the second electrode pad, wherein a lower surface of the current blocking layer is located below the lower surface of the first electrode pad .

In the light emitting device according to the embodiment, the current blocking layer overlapping the second electrode pad is formed on the exposed first conductivity type semiconductor layer from which the active layer and the second conductivity type semiconductor layer are removed, thereby preventing light loss due to light absorption of the active layer So that the light efficiency can be improved.

In the light emitting device according to the embodiment, the current concentrated around the second electrode pad is dispersed by the current blocking layer, thereby maintaining the reliability and improving the light efficiency.

The light emitting device according to the embodiment can improve the light extraction by the current blocking layer having the inclined surface in the concave portion of the light emitting structure.

1 is a perspective view illustrating a light emitting device according to an embodiment.
2 is a plan view showing the light emitting device of FIG.
3 is a cross-sectional view illustrating a light emitting device according to the first embodiment taken along the line I-I 'of FIG.
4 is a cross-sectional view showing A of Fig.
5 is a cross-sectional view illustrating a light emitting device according to a second embodiment taken along the line I-I 'of FIG.
6 is a cross-sectional view showing A in Fig.
7 is a cross-sectional view illustrating a light emitting device according to a third embodiment taken along the line I-I 'of FIG.
8 is a cross-sectional view illustrating a light emitting device according to a fourth embodiment.
9 is a view illustrating a light emitting device package including the light emitting device according to the embodiment.

Hereinafter, a light emitting device and a light emitting device package according to embodiments will be described in detail with reference to the accompanying drawings. In the description of the embodiments, it is to be understood that each layer (film), region, pattern or structure may be formed "on" or "under" a substrate, each layer The terms " on "and " under " include both being formed" directly "or" indirectly " Also, the criteria for top, bottom, or bottom of each layer will be described with reference to the drawings.

1 is a perspective view illustrating a light emitting device according to an embodiment, and FIG. 2 is a plan view illustrating a light emitting device of FIG.

1 and 2, a light emitting device 100 includes a substrate 111, a buffer layer 113, a light emitting structure 120, an electrode layer 131, a first electrode pad 141, a first auxiliary electrode 143 A second electrode pad 151, and a second auxiliary electrode 153. The first electrode pad 151 and the second auxiliary electrode 153 are formed on the same substrate.

The substrate 111 may be a light-transmissive, insulating, or conductive substrate that can grow a gallium nitride-based semiconductor layer. Examples of the substrate include a sapphire (Al ₂ O ₃ ), SiC, Si, GaAs, GaN, ZnO, Any one of Si, GaP, InP, Ge, Ga ₂ O ₃ , LiGaO ₃ , and quartz may be used. A plurality of protrusions may be formed on the upper surface of the substrate 111. The plurality of protrusions may be formed through etching of the substrate 111 or may be formed as a separate light extracting structure such as roughness . The protrusions may include a stripe shape, a hemispherical shape, or a dome shape. The buffer layer 113 may be formed on the substrate 111 to mitigate the difference in lattice constant between the substrate 111 and the nitride based semiconductor layer and function as a defect control layer . The buffer layer 113 may have a value between lattice constants between the substrate 111 and the nitride semiconductor layer. The buffer layer 113 may be formed of an oxide such as a ZnO layer, but is not limited thereto.

The light emitting structure 120 is disposed on the substrate 111. The light emitting structure 120 includes a first conductive semiconductor layer 115, an active layer 117, and a second conductive semiconductor layer 119.

The first conductive semiconductor layer 115 may be formed as a single layer or a multilayer. When the first conductive semiconductor layer 115 is an n-type semiconductor layer, the first conductive semiconductor layer 115 may be a Group III-V compound semiconductor doped with a first conductive dopant. The first conductive type dopant may include Si, Ge, Sn, Se, and Te as an n-type dopant, but is not limited thereto. The first conductive semiconductor layer 115 may include a semiconductor material having a composition formula of In _x Al _y Ga _1-xy N (0? X? 1, 0? _Y? 1, 0? _X + y? . The first conductive semiconductor layer 115 may be formed of one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP and InP.

The active layer 117 may be a single quantum well structure, a multi quantum well (MQW) structure, a quantum-wire structure, or a quantum dot structure. The active layer 117 may include a well layer and a barrier layer formed of a gallium nitride-based semiconductor layer.

For example, the active layer 117 may include one or more of a pair of InGaN / GaN, InGaN / InGaN, GaN / AlGaN, InAlGaN / GaN, GaAs / AlGaAs, InGaAs / AlGaAs, GaInP / AlGaInP, GaP / AlGaP, But the present invention is not limited thereto. The well layer may be formed of a material having a band gap lower than the band gap of the barrier layer.

The barrier layer and the well layer of the active layer 117 may be formed of undoped undoped layers to improve the crystal quality of the active layer, but impurities may be doped in some or all of the active regions to lower the forward voltage. have.

The second conductive semiconductor layer 119 may be formed on the active layer 117 and may be a single layer or a multi-layer structure. When the second conductive semiconductor layer 119 is a p-type semiconductor layer, the second conductive semiconductor layer 119 may be a group III-V compound semiconductor doped with a second conductive dopant. The second conductive dopant may include, but is not limited to, Mg, Zn, Ca, Sr, and Ba as a p-type dopant. The second conductive semiconductor layer 119 may be formed of any one of compound semiconductors such as GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP and GaP.

The first electrode pad 141 and the first auxiliary electrode 143 are located on the first conductive type semiconductor layer 115.

The second electrode pad 151 and the second auxiliary electrode 153 are located on the second conductive type semiconductor layer 119.

The first electrode pad 141, the first auxiliary electrode 143, the second electrode pad 151 and the second auxiliary electrode 153 may be formed of a metal such as Ti, Ru, Rh, Ir, Mg, Zn, , Pd, Co, Ni, Si, Ge, Ag and Au, and alloys thereof.

The electrode layer 131 may be formed of a material having permeability and electrical conductivity as a current diffusion layer. The electrode layer 131 may have a refractive index lower than that of the compound semiconductor layer.

The electrode layer 131 may be formed on the second conductive type semiconductor layer 119 to make ohmic contact with the second conductive type semiconductor layer 119. The electrode layer 131 may be a transparent conductive oxide or a transparent metal layer. For example, the electrode layer 131 may be formed of indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide oxide, AZO (aluminum zinc oxide), ATO (antimony tin oxide), GZO (gallium zinc oxide), ZnO, IrOx, RuOx, NiO and the like.

FIG. 3 is a cross-sectional view illustrating a light emitting device according to a first embodiment taken along the line I-I 'of FIG. 2, and FIG. 4 is a cross-sectional view of FIG.

Referring to FIGS. 3 and 4, the light emitting device according to the first embodiment includes a current blocking layer 160 located in the light emitting structure 120. The current blocking layer 160 has a function of preventing current from being concentrated on the lower portion of the second electrode pad 151.

Here, the first conductive semiconductor layer 115 may include first and second regions 115a and 115b. The first region of the first conductivity type semiconductor layer 115 may be defined as a region exposed from the second conductivity type semiconductor layer 119 and the active layer 117. The first electrode pad 141 is located on the first region. The second region 115b of the first conductivity type semiconductor layer 115 may be defined as an area exposed from the second conductivity type semiconductor layer 119 and the active layer 117. The current blocking layer 160 is located on the second region 115b. The first and second regions 115a and 115b may be spaced apart from each other by a predetermined distance. The current blocking layer 160 and the first electrode pad 141 may be spaced apart from each other by a predetermined distance. The first and second regions 115a and 115b are formed through a mesa etching process to expose the first conductive type semiconductor layer 115 so that the first and second regions 115a and 115b have the same thickness or the same But it is not so limited.

The light emitting structure 120 includes a concave portion, and the concave portion corresponds to the second region 115b. The concave portion has a structure in which the active layer 117 and the second conductivity type semiconductor layer 119 are removed and a part of the upper surface of the first conductivity type semiconductor layer 115 is exposed. The concave portion has a width gradually increasing toward the top. That is, the recess has a side inclined from the upper surface of the first conductivity type semiconductor layer 115.

The current blocking layer 160 may be formed in the concave portion. That is, the current blocking layer 160 is formed on the side surfaces of the first conductivity type semiconductor layer 115, the active layer 117, and the second conductivity type semiconductor layer 119 in the recess, 2-conductivity type semiconductor layer 119. In this case, The current blocking layer 160 is located in a region where the active layer 117 is removed, so that the active layer that absorbs light is removed to prevent light loss.

The current blocking layer 160 may be inclined with respect to the upper surface of the second conductive type semiconductor layer 119 in correspondence with the inclined side surface of the concave portion.

The current blocking layer 160 may be formed of an insulating material such as an oxide or a nitride. For example, the current blocking layer 160 may be formed of at least one selected from the group consisting of Si _x O _y , Si _x N _y , SiO _x N _y , Al ₂ O ₃ , TiO ₂ , and AlN But is not limited thereto.

Alternatively, the current blocking layer 160 may include, but is not limited to, a distributed Bragg reflector (DBR) in which layers having different refractive indices are alternately laminated. The current blocking layer 160 of the distributed Bragg reflector DBR is inclined in the concave portion and reflects light to improve light extraction of the light emitting device.

The current blocking layer 160 may overlap the second electrode pad 151 located on the second conductive semiconductor layer 119. The entirety of the current blocking layer 160 may overlap with the second electrode pad 151. In addition, the entire current blocking layer 160 may overlap with the second auxiliary electrode 153 (FIG. 2).

4, the width W2 of the current blocking layer 160 is equal to the width W1 of the second electrode pad 151. However, the width W2 of the current blocking layer 160 is not limited thereto, The width W2 of the second electrode pad 160 may be equal to or wider than the width W1 of the second electrode pad 151 so that current is not concentrated around the second electrode pad 151. [

The width W2 of the current blocking layer 160 may be equal to or wider than the width (not shown) of the second auxiliary electrode 153. That is, the width of the current blocking layer 160 may be different from a region overlapping with the second electrode pad 151 and a region overlapping with the second auxiliary electrode 153 (FIG. 2).

The electrode layer 131 is located on the current blocking layer 160 and the second conductive type semiconductor layer 119. That is, the electrode layer 131 may cover the current blocking layer 160 exposed to the outside and cover the upper surface of the second conductive type semiconductor layer 119. The electrode layer 131 located in the recess has a cross-sectional shape corresponding to the cross-sectional shape of the current blocking layer 160. That is, the electrode layer 131 located in the concave portion may be inclined with respect to the upper surface of the second conductive type semiconductor layer 119.

The second electrode pad 151 and the second auxiliary electrode 153 may be located on the electrode layer 131 and may overlap the current blocking layer 160. Here, the entire current blocking layer 160 may overlap the second electrode pad 151 and the second auxiliary electrode 153. The second electrode pad 151 and the second auxiliary electrode 153 formed in the concave portion correspond to the shape of the current blocking layer 160 and the upper surface of the second conductivity type semiconductor layer 119 is referred to as a reference As shown in Fig.

The current blocking layer 160 overlapping the second electrode pad 151 and the second auxiliary electrode 153 is electrically connected to the active layer 117 and the second conductive semiconductor layer 119 Is removed and formed on the exposed first conductivity type semiconductor layer 115 to prevent light loss due to light absorption of the active layer 117, so that light efficiency can be improved.

In addition, the light emitting device according to the first embodiment can disperse current concentrated around the second electrode pad 151 and the second auxiliary electrode 153 by the current blocking layer 160.

In addition, the light emitting device according to the first embodiment can improve the light extraction by the current blocking layer 160 having the inclined surface in the concave portion of the light emitting structure 120.

FIG. 5 is a cross-sectional view illustrating a light emitting device according to a second embodiment taken along line I-I 'of FIG. 2, and FIG. 6 is a cross-sectional view of FIG.

The second embodiment can employ the technical features of the first embodiment.

5 and 6, the light emitting device according to the second embodiment is the same as the light emitting device according to the first embodiment except for the current blocking layer 260, and therefore, the same reference numerals are used for the same and the detailed description is omitted , The main features of the second embodiment will be mainly described.

The current blocking layer 260 contacts the first conductive semiconductor layer 115 and contacts the side surface of the active layer 117 and the side surface of the second conductive semiconductor layer 119. The current blocking layer 160 may overlap the second electrode pad 151 located on the second conductive type semiconductor layer 119.

The current blocking layer 260 has a cup-shaped cross-section including an inclined side face. The end of the current blocking layer 260 may be on the same plane as the upper surface of the second conductive semiconductor layer 119. More specifically, the current blocking layer 260 is in contact with the first conductivity type semiconductor layer 115 exposed from the active layer 117 and the second conductivity type semiconductor layer 119, And the side surface of the second conductive type semiconductor layer 119. The end face of the current blocking layer 260 is located in parallel with the upper surface of the second conductive type semiconductor layer 119. The current blocking layer 260 is located in a region where the active layer 117 is removed, thereby preventing light loss due to light absorbed in the active layer.

The width W2 of the current blocking layer 260 is equal to the width W1 of the second electrode pad 151. The width W2 of the current blocking layer 260 is not limited thereto, May be equal to or wider than the width (W1) of the second electrode pad (151).

The current blocking layer 260 may be inclined with respect to the upper surface of the second conductive semiconductor layer 119.

The current blocking layer 260 may be formed of an insulating material such as an oxide or a nitride. For example, the current blocking layer 260 may be formed of at least one selected from the group consisting of Si _x O _y , Si _x N _y , SiO _x N _y , Al ₂ O ₃ , TiO ₂ , and AlN But is not limited thereto.

Alternatively, the current blocking layer 260 may include, but is not limited to, a distributed Bragg reflector (DBR) in which layers having different refractive indices are alternately laminated. The current blocking layer 260 of the distributed Bragg reflector DBR may be formed obliquely in the recess to enhance light extraction.

The light emitting device according to the second embodiment differs from the light emitting device according to the second embodiment in that the current blocking layer 260 overlapping the second electrode pad 151 and the second auxiliary electrode 153 is formed between the active layer 117 and the second conductive semiconductor layer 119 Is removed on the first conductivity type semiconductor layer 115 to prevent light loss due to light absorption of the active layer 117, so that light efficiency can be improved.

In addition, the light emitting device according to the second embodiment can disperse current concentrated around the second electrode pad 151 and the second auxiliary electrode 153 by the current blocking layer 260.

In addition, the light emitting device according to the second embodiment can improve light extraction by the current blocking layer 260 having a sloped surface in the concave portion of the light emitting structure 120.

7 is a cross-sectional view illustrating a light emitting device according to a third embodiment taken along the line I-I 'of FIG.

The third embodiment can adopt the technical features of the first embodiment or the second embodiment, and will be described mainly about the main features of the third embodiment.

The current blocking layer 360 is in contact with the first conductivity type semiconductor layer 115 and contacts the side surface of the active layer 117 and the side surface of the second conductivity type semiconductor layer 119. The current blocking layer 360 may overlap the second electrode pad 151 located on the second conductive type semiconductor layer 119.

The first conductive semiconductor layer 115 includes first and second regions 115a and 115b. The first and second regions 115a and 115b may be defined as regions where the upper surface of the first conductive type semiconductor layer 115 is exposed from the second conductive type semiconductor layer 119 and the active layer 117 . The first electrode pad 141 is located in the first region 115a and the current blocking layer 360 is located in the second region 115b.

The first and second regions 115a and 115b may be spaced apart from each other by a predetermined distance, and the second region 115b may be located below the first region 115a. That is, the lower surface of the current blocking layer 360 may be located below the lower surface of the first electrode pad 141.

The first conductivity type semiconductor layer 115 corresponding to the first region 115a may have a thickness greater than that of the first conductivity type semiconductor layer 115 of the second region 115b. The current blocking layer 360 is located in a region where the active layer 117 is removed, so that the current blocking layer 360 has a function of preventing light loss due to light absorbed in the active layer below the general current blocking layer.

The width of the current blocking layer 360 is equal to the width of the second electrode pad 151. The width of the current blocking layer 360 is not limited to the width of the second electrode pad 151, The widths of the first and second electrodes 22,

The current blocking layer 360 may be inclined with respect to the upper surface of the second conductive semiconductor layer 119.

The current blocking layer 360 may be formed of an insulating material such as an oxide or a nitride. For example, the current blocking layer 360 may be formed of at least one selected from the group consisting of Si _x O _y , Si _x N _y , SiO _x N _y , Al ₂ O ₃ , TiO ₂ , and AlN But is not limited thereto.

The current blocking layer 360 may include, but is not limited to, a distributed Bragg reflector (DBR) in which layers having different refractive indices are alternately laminated. The current blocking layer 360 of the distributed Bragg reflector DBR may be inclined in the concave portion of the second region 115b to improve light extraction. Furthermore, the current blocking layer 360 minimizes the thickness of the first conductivity type semiconductor layer 115 in the second region 115b, thereby enlarging the area for reflecting light, thereby further improving light extraction.

In addition, the light emitting device according to the third embodiment can disperse current concentrated around the second electrode pad 151 and the second auxiliary electrode 153 by the current blocking layer 360.

8 is a cross-sectional view illustrating a light emitting device according to a fourth embodiment.

Referring to FIG. 8, the light emitting device 400 according to the fourth embodiment includes a first electrode pad 441 having a plurality of conductive layers 442, 443, and 445 under the light emitting structure 420, A second electrode pad 451 disposed on the light emitting structure 420 and a current blocking layer 453 disposed between the light emitting structure 420 and the first electrode pad 441 and vertically aligned with the second electrode pad 451, (460), and a support member (423).

The first electrode pad 441 may include a contact layer 442, a reflective layer 443, and a bonding layer 445 located below the second conductive semiconductor layer 419 of the light emitting structure 420 .

The contact layer 442 may be in contact with the lower surface of the second conductive type semiconductor layer 419 and may extend to the lower surface of the current blocking layer 460. The contact layer 442 may be a conductive material such as ITO, IZO, IZTO, IAZO, IGZO, IGTO, AZO, or ATO, or may be a metal of Ni or Ag.

A reflective layer 443 may be formed under the contact layer 442 and the reflective layer 443 may be formed of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, And at least one layer made of a material selected from the group consisting of silicon nitride and silicon nitride. The reflective layer 443 may be in contact with the second conductive type semiconductor layer 419 under the second conductive type semiconductor layer 419, and may be in ohmic contact with a metal or in ohmic contact with a conductive material such as ITO.

A bonding layer 445 may be formed under the reflective layer 443 and the bonding layer 445 may be used as a barrier metal or a bonding metal. The material may include, for example, Ti, Au, Sn, Ni, Cr, Ga, In, Bi, Cu, Ag, and Ta and an optional alloy.

A channel layer 470 may be disposed under the light emitting structure 420. The channel layer 470 is formed along the lower surface of the second conductive type semiconductor layer 419 and may be formed in a ring shape, a loop shape, or a frame shape. The channel layer 470 is an ITO, IZO, IZTO, IAZO, IGZO, IGTO, AZO, ATO, SiO 2, SiO x, SiO x N y, Si 3 N 4, at least one of Al ₂ O _3, TiO ₂ . The inner side of the channel layer 470 is disposed below the second conductive type semiconductor layer 419 and the outer side of the channel layer 470 is located further outward than the side surface of the light emitting structure 420.

A support member 423 is formed under the bonding layer 445 and the support member 423 may be formed of a conductive material such as copper-copper, gold-gold, nickel (Ni-nickel), molybdenum (Mo), copper-tungsten (Cu-W), and carrier wafers (e.g., Si, Ge, GaAs, ZnO, SiC and the like).

As another example, the support member 423 may be embodied as a conductive sheet. The first electrode pad 441 may include the support member 423 and at least one or more layers of the first electrode pad 441 may be formed to have the same width as the support member 423 .

A light extraction structure such as a roughness may be formed on the upper surface of the first conductive type semiconductor layer 415. The second electrode pad 451 may be disposed on a flat surface of the upper surface of the first conductive type semiconductor layer 415, but the present invention is not limited thereto. An insulating layer (not shown) may be further formed on the side surfaces and the upper surface of the light emitting structure 420, but the present invention is not limited thereto.

The current blocking layer 460 overlaps with the second electrode pad 451 and has a function of preventing current from concentrating on a lower portion of the second electrode pad 451.

The light emitting structure 420 includes a concave portion at a central portion thereof and the concave portion has a structure in which the active layer 417 and the second conductivity type semiconductor layer 419 are removed to expose the first conductivity type semiconductor layer 415 . The concave portion has a width gradually narrower toward the upper side. That is, the recess has a side inclined with respect to the lower surface of the first conductivity type semiconductor layer 415.

The current blocking layer 460 may be formed in the recess. That is, the current blocking layer 460 is formed on the side surfaces of the first conductivity type semiconductor layer 415, the active layer 417 and the second conductivity type semiconductor layer 419 in the recess, 2 conductivity type semiconductor layer 419. In this case, The current blocking layer 460 is located in a region where the active layer 417 is removed, so that the active layer that absorbs light is removed to prevent light loss.

The current blocking layer 460 may be formed of an insulating material such as an oxide or a nitride. For example, the current blocking layer 460 may be formed of at least one selected from the group consisting of Si _x O _y , Si _x N _y , SiO _x N _y , Al ₂ O ₃ , TiO ₂ , and AlN But is not limited thereto.

Alternatively, the current blocking layer 460 may include, but is not limited to, a distributed Bragg reflector (DBR) in which layers having different refractive indices are alternately laminated. The current blocking layer 460 of the distributed Bragg reflector DBR is inclined in the concave portion and reflects light to improve light extraction of the light emitting device.

The width of the current blocking layer 460 may be equal to or greater than the width of the second electrode pad 451.

The current blocking layer 460 overlapping with the second electrode pad 451 is electrically connected to the first conductive type semiconductor layer 419 in which the active layer 417 and the second conductive semiconductor layer 419 are removed, The light efficiency can be improved because it is formed on the semiconductor layer 415 to prevent light loss due to light absorption of the active layer 417.

In addition, the light emitting device according to the fourth embodiment can disperse current concentrated around the second electrode pad 451 by the current blocking layer 460.

Further, the light emitting device according to the fourth embodiment can improve the light extraction by the current blocking layer 460 having the inclined surface in the concave portion of the light emitting structure 420.

9 is a view showing a light emitting device package having the light emitting element of FIG.

9, the light emitting device package includes a body 510, a first lead electrode 521 and a second lead electrode 523 at least partially disposed on the body 510, The light emitting device 400 electrically connected to the first lead electrode 521 and the second lead electrode 523 on the body 510 and the molding member 530 surrounding the light emitting device 400 ).

The body 510 may be formed of a silicon material, a synthetic resin material, or a metal material.

The first lead electrode 521 and the second lead electrode 523 are electrically separated from each other and may be formed to penetrate the inside of the body 510. That is, some of the first lead electrode 521 and the second lead electrode 523 may be disposed inside the cavity, and other portions may be disposed outside the body 510.

The first lead electrode 521 and the second lead electrode 523 may supply power to the light emitting device 400 and increase light efficiency by reflecting the light generated from the light emitting device 400, And may also function to discharge heat generated in the light emitting device 400 to the outside.

The light emitting device package may include the light emitting device 400 according to the fourth embodiment having excellent light efficiency as shown in FIG. Therefore, the light emitting device package has an advantage of improved light efficiency. In addition, the light emitting device package of the embodiment may include the light emitting device according to the first to third embodiments shown in FIGS. 3, 4, and 7. The light emitting device or the light emitting device package according to the embodiment may include light Unit. ≪ / RTI > The light unit includes a structure in which a plurality of light emitting devices or light emitting device packages are arrayed, and may include an illumination light, a traffic light, a vehicle headlight, an electric signboard, and the like.

The features, structures, effects and the like described in the embodiments are included in at least one embodiment and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects and the like illustrated in the embodiments can be combined and modified by other persons skilled in the art to which the embodiments belong. Accordingly, the contents of such combinations and modifications should be construed as being included in the scope of the embodiments.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. It can be seen that the modification and application of branches are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that the present invention may be embodied in many other specific forms without departing from the spirit or essential characteristics thereof.

115: first conductive type semiconductor layer 117: active layer
119: second conductive type semiconductor layer 160, 260, 360, 460: current blocking layer
141, 441: first electrode pad 151, 451: second electrode pad

Claims (13)

A first conductive semiconductor layer; An active layer disposed on the first conductive semiconductor layer; And a second conductive semiconductor layer disposed on the active layer;
A first electrode pad located in a first region of the first conductivity type semiconductor layer;
A second electrode pad disposed on the second conductive semiconductor layer; And
And a current blocking layer located in a second region of the first conductivity type semiconductor layer and overlapped with the second electrode pad,
Wherein the current blocking layer is in contact with the exposed first conductivity type semiconductor layer after the active layer is removed. The method according to claim 1,
Wherein the current blocking layer is in contact with a side surface of the active layer and a side surface of the second conductivity type semiconductor layer. The method according to claim 1,
And the current blocking layer extends to an upper surface of the second conductivity type semiconductor layer. The method according to claim 1,
Wherein the current blocking layer has a cup-shaped cross section, and an end of the current blocking layer is on the same plane as the upper surface of the second conductivity type semiconductor layer. The method according to claim 1,
And a width of the current blocking layer is equal to or greater than a width of the second electrode pad and a width of the auxiliary electrode. The method according to claim 1,
Wherein the light emitting structure includes a concave portion in which the active layer and the second conductive type semiconductor layer are removed, and the concave portion corresponds to the second region. The method according to claim 6,
Wherein the recess has a width that increases as the distance from the first conductivity type semiconductor layer increases. The method according to claim 1,
Wherein the first region is located on one side of the first conductivity type semiconductor layer and the second region is located on the other side of the first conductivity type semiconductor layer. 9. The method of claim 8,
And the current blocking layer is positioned on the first electrode pad. A first conductive semiconductor layer; An active layer disposed on the first conductive semiconductor layer; And a second conductive semiconductor layer disposed on the active layer;
A first electrode pad located in a first region of the first conductivity type semiconductor layer;
A second electrode pad disposed on the second conductive semiconductor layer; And
And a current blocking layer located in a second region of the first conductivity type semiconductor layer and overlapped with the second electrode pad,
And the lower surface of the current blocking layer is located below the lower surface of the first electrode pad. 11. The method of claim 10,
And a width of the current blocking layer is equal to or greater than a width of the second electrode pad and a width of the auxiliary electrode. 11. The method of claim 10,
Wherein the first conductivity type semiconductor layer has a thickness greater than a thickness of the first region. A light emitting device package comprising the light emitting device according to any one of claims 1 to 10.

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