KR101781217B1 - Light emitting device and light emitting device package - Google Patents

Abstract

A light emitting device according to an embodiment includes a support substrate, a first conductivity type semiconductor layer on the support substrate, a second conductivity type semiconductor layer, and an active layer between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer A first pad portion and a second pad portion disposed closer to the outermost portion from the center region of the upper surface of the light emitting structure layer; and a second electrode pad extending from at least one of the first pad portion and the second pad portion, Wherein the first pad portion is disposed on a first region closer to the first edge than the center region on the upper surface of the light emitting structure layer and the second pad portion is disposed on the first region closer to the first edge than the second edge on the opposite side of the first edge, And a second region that is spaced apart from at least one of the first direction and the second direction orthogonal to the first direction.

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 diodes (LEDs) are a type of semiconductor devices that convert electrical energy into light. Light emitting diodes have advantages of low power consumption, semi-permanent lifetime, fast response speed, safety, and environmental friendliness compared with conventional light sources such as fluorescent lamps and incandescent lamps.

Therefore, much research has been conducted to replace an existing light source with a light emitting diode, and there is an increasing tendency to use a light emitting element as a light source for various lamps, liquid crystal display devices, electric sign boards, to be.

Embodiments provide a light emitting device and a light emitting device package having a new structure.

In addition, the embodiment provides a light emitting device and a light emitting device package that reduce the operating voltage.

In addition, the embodiment provides a light emitting device and a light emitting device package that improves an operating voltage according to a position of an electrode pad portion where wire bonding is performed.

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Also, an embodiment includes a support substrate; A light emitting structure layer including a first conductive semiconductor layer, a second conductive semiconductor layer, and an active layer between the first conductive semiconductor layer and the second conductive semiconductor layer on the supporting substrate; A first pad portion and a second pad portion disposed closer to the outermost portion from the center region of the upper surface of the light emitting structure layer and an external electrode extending from at least one of the first pad portion and the second pad portion, Wherein the first pad portion is disposed on a first region closer to the outermost portion than the center region on the upper surface of the light emitting structure layer and the second pad portion is disposed on the first side of the upper surface of the light emitting structure layer The first line segment extending from the first region and the second line segment connecting the first region and the opposite side of the first region are spaced at an angle of at least 10 degrees.

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The embodiment also includes a package body; A first electrode layer and a second electrode layer provided on the package body; And a light emitting element electrically connected to the first electrode layer and the second electrode layer, wherein the light emitting element comprises: a support substrate; A light emitting structure layer including a first conductive semiconductor layer, a second conductive semiconductor layer, and an active layer between the first conductive semiconductor layer and the second conductive semiconductor layer on the supporting substrate; A first pad portion and a second pad portion disposed closer to the outermost portion from the center region of the upper surface of the light emitting structure layer and an external electrode extending from at least one of the first pad portion and the second pad portion, Wherein the first pad portion is disposed on a first region closer to the outermost portion than the center region on the upper surface of the light emitting structure layer and the second pad portion is disposed on the first side of the upper surface of the light emitting structure layer The first line segment extending from the first region and the second line segment connecting the first region and the opposite side of the first region are spaced at an angle of at least 10 degrees.

The embodiment can reduce the operating voltage by arranging at least two pad portions on which the wire bonding is made at predetermined positions on the electrode.

Meanwhile, various other effects will be directly or implicitly disclosed in the detailed description according to the embodiment of the present invention to be described later.

1 is a sectional view of a light emitting device according to an embodiment;
FIG. 2 illustrates an example of a planar shape of an electrode in a light emitting device according to an embodiment; FIG.
FIGS. 3A and 3B are views showing another example of the shape of the electrode on the plane in the light emitting device according to the embodiment; FIG.
4 is a view showing another example of the shape of the electrode on the plane in the light emitting device according to the embodiment;
5 is a view illustrating a position of a pad portion for measuring an operating voltage in a light emitting device according to an embodiment;
6 is a diagram illustrating an operation voltage according to a position of a pad portion in a light emitting device according to an embodiment;
7 to 14 are views for explaining a method of manufacturing a light emitting device according to an embodiment;
15 is a sectional view of a light emitting device package including a light emitting device according to an embodiment;
16 is a view illustrating a backlight unit including a light emitting device or a light emitting device package according to an embodiment;
17 is a view showing a lighting unit including a light emitting device or a light emitting device package according to the embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. The following terms are defined in consideration of the functions of the present invention, and may be changed according to the intentions or customs of the user, the operator, and the like. Therefore, the definition should be based on the contents throughout this specification.

Also, in the description of the embodiments, it is to be understood that each layer (film), area, pattern or structure may be referred to as being "on" or "under" ) "Includes both those formed directly or through another layer. The criteria for top / bottom or bottom / bottom of each layer are described with reference to the drawings.

The thickness or the size of each layer (film), region, pattern or structure in the drawings may be modified for clarity and convenience of explanation, and thus does not entirely reflect the actual size.

Hereinafter, a light emitting device, a light emitting device manufacturing method, a light emitting device package, and an illumination system according to embodiments will be described with reference to the accompanying drawings.

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

1, the light emitting device 100 according to the present embodiment includes a support substrate 180, a light emitting structure layer 135 that generates light on the support substrate 180, a light emitting structure layer 135, And an electrode 115 on the substrate. The light emitting structure layer 135 includes a first conductive semiconductor layer 110, an active layer 120 and a second conductive semiconductor layer 130. The first conductive semiconductor layer 110 and the second conductive semiconductor layer 130 Electrons and holes provided from the conductive semiconductor layer 130 may be recombined in the active layer 120 to generate light.

A bonding layer 170, a reflective layer 160, an ohmic layer 150, a channel layer 140, a current blocking layer 145, and the like may be disposed between the supporting substrate 180 and the light emitting structure layer 135, A passivation layer 190 may be formed on a side surface of the light emitting structure layer 135. This will be described in more detail as follows.

The supporting substrate 180 supports the light emitting structure layer 135 and may supply power to the light emitting structure layer 135 together with the electrode 115. The supporting substrate 180 may be a conductive supporting substrate including at least one of Cu, Au, Ni, Mo, Cu-W, Si, Ge, GaAs, ZnO, and SiC. However, the embodiment is not limited to this, and it is also possible to use an insulating substrate instead of the conductive supporting substrate and to form a separate electrode.

The support substrate 180 may have a thickness of 30 to 500 탆. However, it should be apparent to those skilled in the art that the embodiment is not limited thereto and may vary depending on the design of the light emitting device 100.

A bonding layer 170 may be formed on the supporting substrate 180. The bonding layer 170 may be formed as a bonding layer or a seed layer under the reflective layer 160 and the channel layer 140. The bonding layer 170 is exposed to the outer surface and contacts the reflective layer 160, the end of the ohmic layer 150 and the channel layer 140 to form the reflective layer 160, the ohmic layer 150, and the channel layer 140 ) Can be strengthened.

The bonding layer 170 includes a barrier metal or a bonding metal. For example, the bonding layer 170 may be formed of a metal such as Cu, Ni, Ag, Mo, Al, Au, Nb, W, Ti, Cr, Ta, Al, Pd, Pt, Si, Al- Cu, Sb, Al-Zn, Al-Mg, Al-Ge, Pd-Pb, Ag-Sb, Au-In, Al-Cu-Si, Ag-Cd- Ag-Cu-Zn, Au-Si, Au-Ge, Au-Ni, Au-Cu, Au-Ag-Cu, , Cu-Zn, Cu-P, Ni-P, Ni-Mn-Pd, Ni-P and Pd-Ni.

A reflective layer 160 may be formed on the bonding layer 170. The reflection layer 160 reflects light generated in the light emitting structure layer 135 and directed toward the reflection layer 160 to improve the luminous efficiency of the light emitting device 100.

The reflective layer 160 may include at least one of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, Hf and alloys thereof. The reflective layer 160 may be formed of any one of the above-mentioned metals or alloys, indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium tin a transparent conductive material such as indium gallium oxide (ITO), indium gallium zinc oxide (IGZO), aluminum zinc oxide (AZO), or antimony tin oxide (ATO). For example, the reflective layer 160 may include a layered structure of IZO / Ni, AZO / Ag, IZO / Ag / Ni, AZO / Ag / Ni, Ag / Cu and Ag / Pd / Cu.

The ohmic layer 150 may be formed on the reflective layer 160. The ohmic layer 150 may be in ohmic contact with the second conductive semiconductor layer 130 to supply power to the light emitting structure layer 135 smoothly. The ohmic layer 150, ITO, IZO, IZTO, IAZO , IGZO, IGTO, AZO, ATO, GZO (gallium zinc oxide), IrO x, RuO x, RuO x / ITO, Ni, Ag, Pt, Ni / IrO _x / Au, or Ni / IrO _x / Au / ITO.

 In this embodiment, the upper surface of the reflective layer 160 is in contact with the ohmic layer 150. However, when the reflective layer 160 is in contact with the channel layer 140 or the light emitting structure layer 135 It would be possible.

A current blocking layer 145 may be formed on the inner side between the ohmic layer 150 and the second conductive semiconductor layer 130. The current blocking layer 145 may include _{ZnO, SiO 2, SiON, Si} 3 N 4, Al 2 O 3, TiO 2, Ti, Al, at least one of Cr.

The top surface of the current blocking layer 145 is in contact with the second conductivity type semiconductor layer 130 and the bottom and side surfaces of the current blocking layer 145 are in contact with the ohmic layer 150.

The current blocking layer 145 may be formed so as to overlap at least a part of the current blocking layer 145 in the vertical direction with respect to the electrode 115. Accordingly, the phenomenon that current is concentrated at the shortest distance between the electrode 115 and the supporting substrate 180 is alleviated So that the luminous efficiency of the luminous means 100 can be improved.

Meanwhile, a channel layer 140 may be formed on the outer side between the bonding layer 170 and the second conductivity type semiconductor layer 130. That is, the channel layer 140 may be formed in a peripheral region between the light emitting structure layer 135 and the bonding layer 170, thereby forming a ring shape, a loop shape, a frame shape, or the like.

The channel layer 140 may be formed of a material having electrical conductivity lower than that of the reflective layer 160 or the bonding layer 170 or a material forming a Schottky contact with the second conductive semiconductor layer 130 . For example, the channel layer 140, ITO, IZO, IZTO, IAZO, IGZO, IGTO, AZO, ATO, ZnO, SiO _2, SiO _x, SiO _x N _y, Si ₃ N _4, Al ₂ O ₃ , TiO _x , TiO ₂ , Ti, Al, or Cr.

The second conductive semiconductor layer 130 and the passivation layer 190 are in contact with the upper surface of the channel layer 140 and the ohmic layer 150 and the bonding layer 170 are formed on the lower surface and the side surface of the channel layer 140, Can be contacted.

In this embodiment, the ohmic layer 150 is in contact with the bottom surface and the side surface of the channel layer 140. However, the present invention is not limited thereto. Accordingly, the ohmic layer 150 and the channel layer 140 may be spaced apart from each other, or the ohmic layer 150 may be in contact with only the side surface of the channel layer 140. Also, the channel layer 140 may be formed between the reflective layer 160 and the ohmic layer 150.

In addition, the channel layer 140 may partially overlap the light emitting structure layer 135 in the vertical direction. The channel layer 140 may increase the distance between the bonding layer 170 and the active layer 120 to reduce the possibility of an electrical short circuit between the bonding layer 170 and the active layer 120. In addition, the channel layer 140 can prevent moisture and the like from penetrating into the gap between the light emitting structure layer 135 and the support substrate 180.

In addition, the channel layer 140 can prevent an electrical short circuit from occurring in the chip separation process. More specifically, when isolation etching is performed to separate the light emitting structure layer 135 into unit chip regions, the debris generated in the bonding layer 170 may be transferred to the second conductivity type semiconductor layer 130, And the active layer 120 or between the active layer 120 and the first conductive semiconductor layer 110 to cause an electrical short circuit. The channel layer 140 prevents such an electrical short circuit. Accordingly, the channel layer 140 may be formed of an insulating material that does not break or break when the isolation is etched, or that does not cause an electrical short circuit even if a small portion of the channel layer 140 is broken or a small amount of debris is generated.

A light emitting structure layer 135 may be formed on the ohmic layer 150 and the channel layer 140. The side surface of the light emitting structure layer 135 may be inclined by isolation etching that divides a plurality of chips into unit chip regions.

The light emitting structure layer 135 may include a plurality of Group III-V compound semiconductor layers, and may include a first conductive semiconductor layer 110, a second conductive semiconductor layer 130, And may include an active layer 120. At this time, the second conductive type semiconductor layer 130 is located on the ohmic layer 150 and the channel layer 140, the active layer 120 is located on the second conductive type semiconductor layer 130, The conductive semiconductor layer 110 may be located on the active layer 120.

A first conductivity type InGaN / GaN superlattice structure or an InGaN / InGaN superlattice structure (not shown) may be formed between the first conductive semiconductor layer 110 and the active layer 120. A second conductivity type AlGaN layer (not shown) may be formed between the second conductive semiconductor layer 130 and the active layer 120.

The first conductive semiconductor layer 110 may include a compound semiconductor of a Group III-V element doped with the first conductive dopant. For example, the first conductivity type semiconductor layer 110 may include an n-type semiconductor layer. The n-type semiconductor layer is doped with an n-type dopant to a semiconductor material having a composition formula of In _x Al _y Ga _{1 -x- y} N (0? X? 1, 0? _Y ? 1, . For example, n-type dopants such as Si, Ge, Sn, Se and Te can be formed on GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP and AlGaInP. The first conductive semiconductor layer 110 may be a single layer or a multilayer, but is not limited thereto.

The active layer 120 may be formed of any one of a single quantum well structure, a multi quantum well structure (MQW), a quantum dot structure, and a quantum wire structure. However, the present invention is not limited thereto.

The active layer 120 may be formed of a semiconductor material having a composition formula of In _x Al _y Ga _{1 -x- y} N (0? X? 1, 0? _Y? 1, 0? _X + y? When the active layer 120 is formed of a multiple quantum well structure, the active layer 120 may be formed by stacking a plurality of well layers and a plurality of barrier layers. For example, the active layer 120 may be formed by alternately stacking a well layer including InGaN and a barrier layer including GaN.

A cladding layer (not shown) doped with an n-type or p-type dopant may be formed on and / or below the active layer 120, and the cladding layer may include an AlGaN layer or an InAlGaN layer. The band gap of the barrier layer may be larger than the band gap of the well layer, and the band gap of the cladding layer may be larger than the band gap of the active layer.

The second conductive semiconductor layer 130 may include a compound semiconductor of a Group III-V element doped with a second conductive dopant. For example, the second conductive semiconductor layer 130 may include a p-type semiconductor layer. This p-type semiconductor layer is doped with a p-type dopant to a semiconductor material having a composition formula of In _x Al _y Ga _{1 -x- y} N (0? X? 1, 0? _Y? . For example, a p-type dopant such as Mg, Zn, Ca, Sr, or Br may be included in GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP and AlGaInP. The second conductive semiconductor layer 130 may be a single layer or a multilayer, but is not limited thereto.

In this embodiment, the first conductive semiconductor layer 110 includes an n-type semiconductor layer and the second conductive semiconductor layer 130 includes a p-type semiconductor layer. However, the present invention is not limited thereto Do not. That is, the first conductive semiconductor layer 110 may include a p-type semiconductor layer, and the second conductive semiconductor layer 130 may include an n-type semiconductor layer. In addition, another n-type or p-type semiconductor layer (not shown) may be formed under the second conductive type semiconductor layer 130. Accordingly, the light emitting structure layer 135 may have at least one of np, pn, npn, and pnp junction structures.

In addition, the doping concentrations of the dopants in the first conductivity type semiconductor layer 110 and the second conductivity type semiconductor layer 130 may be uniform or non-uniform. That is, the structure of the light emitting structure layer 135 may be variously modified, but is not limited thereto.

A light extracting structure 112 may be formed on the upper surface of the light emitting structure layer 135. The light extracting structure 112 may minimize the amount of light reflected from the surface to improve the light extraction efficiency of the light emitting device 100. The light extracting structure 112 may have a random shape and arrangement, or may be formed to have a regular shape and arrangement. In this embodiment, the upper surface of the first conductive semiconductor layer 110 may be formed with a roughness pattern to increase the light extraction efficiency.

An electrode 115 is formed on the light emitting structure layer 135, more specifically, on the top surface of the first conductive semiconductor layer 110. The electrode 115 may be branched into a predetermined pattern, but the present invention is not limited thereto.

In addition, the electrode 115 may have at least two pad portions (not shown) and at least one electrode portion 115a and 115b connected to the pad portion (not shown) may have the same or different lamination structure But is not limited thereto. Here, the pad portion (not shown) refers to a portion where wire bonding is performed on the electrode 115.

In the present embodiment, the electrode 115 includes a pad portion (not shown) and an external electrode 115a and an internal electrode 115b extending from the pad portion. However, the at least one shape of the electrode portion may be formed of only the external electrode 115a. In addition, although the upper surface of the electrode 115 is a plane surface, a roughness pattern may be formed on the upper surface of the electrode 115, but the present invention is not limited thereto.

The electrode 115 may be formed of a metal such as Au, Pd, Pt, Ru, Re, Mg, Zn, Hf, Ta, Rh, Ir, W, Ti, Ag, Cr, Mo, Nb, Al, Ni, Cu, Alloy. ≪ / RTI >

Meanwhile, a passivation layer 190 may be formed on at least one side of the light emitting structure layer 135. The passivation layer 190 may be formed on the upper surface of the first conductive semiconductor layer 110 and the upper surface of the channel layer 140, but the present invention is not limited thereto.

The passivation layer 190 may be formed to electrically protect the light emitting structure layer 135, for example, as SiO _2, SiO _x, SiO _x N _y, Si ₃ N _4, Al ₂ O ₃ But the present invention is not limited thereto.

2 is a view showing an example of the shape of the electrode on a plane in the light emitting device according to the embodiment. FIG. 1 shows the electrode cut along the line I-I '.

1 and 2, the electrode 115 is formed on the first conductivity type semiconductor layer 110, and a first pad (not shown) disposed closer to the outermost portion from the center region of the upper surface of the light emitting structure layer, A second pad portion, and electrode portions 115a and 115b extending from at least one of the first pad portion and the second pad portion.

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The electrode 115 includes the external electrode 115a extending along the upper surface of the first conductivity type semiconductor layer 110 and the first portion of the external electrode 115a and the external electrode 115a. And an internal electrode 115b connecting the second portion of the first electrode 115a. The internal electrode 115b may be disposed in a region surrounded by the external electrode 115a. Although two internal electrodes 115b1 and 115b2 are illustrated in this embodiment, the present invention is not limited thereto.

As shown in FIG. 2, the external electrode 115a includes a first external electrode 115a1, a second external electrode 115a2, a third external electrode 115a3, and a fourth external electrode 115a4. The internal electrode 115b includes a first internal electrode 115b1 and a second internal electrode 115b2.

At least a portion of the external electrode 115a may be formed within 50 占 퐉 from the outermost portion of the upper surface of the first conductive semiconductor layer 110. The external electrode 115a may contact the passivation layer 180 It is possible. For example, at least a portion of each of the first external electrode 115a1, the second external electrode 115a2, the third external electrode 115a3, and the fourth external electrode 115a4 is electrically connected to the first conductive semiconductor layer 110 ) From the outermost part of the upper surface.

The external electrode 115a may be arranged in a rectangular shape having four sides and four vertexes. The external electrode 115a may include a first external electrode 115a1 and a second external electrode 115a2 extending in the first direction, And a third external electrode 115a3 and a fourth external electrode 115a4 extending in a second direction perpendicular to the first external electrode 115a1.

The internal electrode 115b includes a first internal electrode 115b1 extending in the second direction and connecting the first external electrode 115a1 and the second external electrode 115a2 extending in the first direction, Electrode 115b2.

The pad portion 115c includes a first pad portion 115c1 and a second pad portion 115c2. The first pad portion 115c1 is disposed at a vertex portion where the second external electrode 115a2 meets the third external electrode 115a3 and the second pad portion 115c2 is disposed at a vertex portion where the first external electrode 115a2 And the fourth external electrode 115a4. Meanwhile, the first pad portion 115c1 may be disposed at another vertex portion, and the second pad portion 115c2 is positioned on the external electrode that is not adjacent to the first pad portion 115c1.

The second pad portion 115c2 may be formed such that a line connecting the first pad portion 115c1 and the second pad portion 115c2 is electrically connected to the second external electrode 115a2, And a line segment connecting the first pad unit 115c1 and the first pad unit 115c1 are located in a region larger than a predetermined angle with respect to the third external electrode 115a3. For example, the second pad portion 115c2 may be formed such that a line segment connecting the first pad portion 115c1 with the first pad portion 115c1 extends from an area of 10 degrees or more to a region of 80 degrees or less from the second external electrode 115a2 Located.

More preferably, the second pad portion 115c2 is formed in a region of the region where the first external electrode 115a1 and the fourth external electrode 115a4, which are opposed to the first pad portion 115c1, Located.

Meanwhile, the position of the second pad portion may be expressed as a distance ratio rather than an angle as follows.

2, the first pad portion 115c1 is located at a portion where the second external electrode 115a2 contacts the third external electrode 115a3, and the second pad portion 115c2 is located at a portion where the second external electrode 115a2 contacts the third external electrode 115a3. And is positioned on the first external electrode 115a1 and the fourth external electrode 115a4.

When the shape of the external electrode 115a is a square or a rectangle having four sides and four vertexes, the length of the first external electrode 115a1 and the length of the second external electrode 115a2 are A, It is assumed that the length of the electrode 115a3 and the length of the fourth external electrode 115a4 are B, respectively.

The length from the third external electrode 115a3 to the second pad portion 115c2 located on the first external electrode 115a1 is C and the length from the second external electrode 115a2 to the fourth external electrode 115a1 is C, And the length to the second pad portion 115c2 located on the second pad portion 115a4 is D. [

First, the position X of the second pad portion 115c2 positioned on the first external electrode 115a1 is expressed by a distance ratio,

A is the length of the first external electrode 115a1, B is the length of the third external electrode 115a3, and C is the length of the second external electrode 115a1 on the third external electrode 115a3. Is the distance between the line segment connecting the first pad portion and the second pad portion and the third external electrode.

That is, the position X of the second pad portion 115c2 is set such that a line segment connecting the first pad portion 115c1 with the first pad portion 115c1 is diagonally positioned from a region over a predetermined angle with respect to the third external electrode 115a3 To-side. More preferably, the line segment connecting the first pad unit 115c1 and the first pad unit 115c1 is a region of 10 degrees or more with respect to the third external electrode 115a3.

Next, the position (Y) of the second pad portion 115c2 positioned on the fourth external electrode 115a4 is expressed by a distance ratio as shown in Equation (2).

A is the length of the second external electrode 115a2, B is the length of the fourth external electrode 115a3, D is the second pad located on the fourth external electrode 115a4 at the second external electrode 115a2, Is a length between the first pad portion and the second pad portion and an angle between the second external electrode and the line segment connecting the first pad portion and the second pad portion.

In other words, the position Y of the second pad portion 115c2 may be determined such that a line segment connecting the first pad portion 115c1 with the first pad portion 115c1 is diagonally positioned from a region over a predetermined angle with respect to the second external electrode 115a2 To-side. More preferably, the line segment connecting the first pad unit 115c1 and the first pad unit 115c1 is an area of 10 degrees or more with respect to the second external electrode 115a2.

3A and 3B are views showing another example of the shape of the electrode on the plane in the light emitting device according to the embodiment.

3A and 3B, the electrode 115 is formed on the first conductivity type semiconductor layer 110, and the electrode 115, which extends along the periphery of the top surface of the first conductivity type semiconductor layer 110, And an internal electrode 115b connecting the first portion of the external electrode 115a and the second portion of the external electrode 115a. The internal electrode 115b may be disposed in a region surrounded by the external electrode 115a.

The external electrode 115a includes a first external electrode 115a1, a second external electrode 115a2, a third external electrode 115a3, and a fourth external electrode 115a4. The internal electrode 115b may include a first internal electrode 115b1 and a second internal electrode 115b2.

At least a portion of the external electrode 115a may be formed within 50 占 퐉 from the outermost portion of the upper surface of the first conductive semiconductor layer 110. The external electrode 115a may contact the passivation layer 180 It is possible.

The external electrode 115a may be arranged in a rectangular shape having four sides and four vertexes. The external electrode 115a may include a first external electrode 115a1 and a second external electrode 115a2 extending in the first direction, And a third external electrode 115a3 and a fourth external electrode 115a4 extending in a second direction perpendicular to the first external electrode 115a1.

The internal electrode 115b includes a first internal electrode 115b1 extending in the second direction and connecting the first external electrode 115a1 and the second external electrode 115a2 extending in the first direction, Electrode 115b2. Although two internal electrodes 115b1 and 115b2 are illustrated in the embodiment, the present invention is not limited thereto.

The pad portion 115c may include a first pad portion 115c1 and a second pad portion 115c2. The first pad portion 115c1 may be formed on the second external electrode 115a2, And the second pad portion 115c2 is disposed on the first external electrode 115a1 and the fourth external electrode 115a4.

3A, the portion where the second external electrode 115a2 and the fourth external electrode 115a4 meet and the portion where the first external electrode 115a1 and the third external electrode 115a3 meet are connected to each other The electrode shown in FIG. 3B has a portion where the second outer electrode 115a2 and the fourth outer electrode 115a4 meet, and a portion where the first outer electrode 115a1 and the third outer electrode 115a3 meet Thereby forming an open structure.

4 is a view showing another example of the shape of the electrode on the plane in the light emitting device according to the embodiment. Hereinafter, the description of the same or extremely similar portions as those described above will be omitted, and only different portions will be described in detail.

Referring to FIG. 4, the width of the second external electrode 115a2 and the third external electrode 115a3 extending outward with respect to the first pad portion 115c1 of the electrode is away from the first pad portion 115c1 It can be formed into a tapered structure. Also, the width of the fourth external electrode 115a4 extending outward with respect to the second pad portion 115c2 of the electrode may be made narrower as the distance from the second pad portion 115c2 is increased.

5 is a view showing the position of a pad unit for measuring an operating voltage in the light emitting device according to the embodiment. FIG. 6 is a diagram illustrating an operation voltage according to a position of a pad portion in a light emitting device according to an embodiment.

5, the first pad portion 115c1 is located at a portion where the second external electrode 115a2 contacts the third external electrode 115a3, and the second pad portion 115c2 is positioned at a portion where the fourth external electrode 115b, 115a4, 115a4, 115a4, respectively.

Here, a current of 350 mA is supplied to the light emitting element, and an operation voltage according to the position of the second pad portion 115c2 is measured, as shown in Table 1 and FIG.

 The position of the second pad portion A point Point B Point C Point D
Operating voltage (V)

3.38
3.34
3.32
3.33

Referring to Table 1 and FIG. 6, when the second pad portion 115c2 is located at the A point (reference point), the operation voltage is the highest and the second pad portion 115c2 is at the B, C, If it is located, it can be confirmed that the operating voltage is relatively low. Accordingly, the operation voltage can be reduced by disposing the second pad portion 115c2 in a region of a predetermined angle or more from a region above a predetermined angle with respect to the second external electrode 115a2.

Hereinafter, a method of manufacturing a light emitting device according to an embodiment will be described in detail. However, the contents overlapping with the above contents will be omitted or briefly explained.

7 to 14 are views for explaining a method of manufacturing a light emitting device according to an embodiment.

Referring to FIG. 7, a light emitting structure layer 135 is formed on a growth substrate 101.

The growth substrate 101 may be formed of at least one of, for example, sapphire (Al ₂ O ₃ ), SiC, GaAs, GaN, ZnO, Si, GaP, InP and Ge. For example, the growth substrate 101 grows the light emitting structure layer, and the sapphire substrate may be used.

The light emitting structure layer 135 may be formed by successively growing the first conductive semiconductor layer 110, the active layer 120, and the second conductive semiconductor layer 130 on the growth substrate 101 .

The light emitting structure layer 135 may be formed using a metal organic chemical vapor deposition (MOCVD) method, a chemical vapor deposition (CVD) method, a plasma enhanced chemical vapor deposition (PECVD) method, Molecular beam epitaxy (MBE), or hydride vapor phase epitaxy (HVPE), but the present invention is not limited thereto.

A buffer layer (not shown) and / or an unshown semiconductor layer (not shown) may be formed between the light emitting structure layer 135 and the growth substrate 101 to mitigate the lattice constant difference. For example, the undoped nitride layer may be formed of an undoped-GaN layer. For example, the undoped nitride layer may be formed of an undoped-GaN layer. . A buffer layer may be formed between the undoped semiconductor layer and the growth substrate 101. In addition, the above-described undoped semiconductor layer is not necessarily formed, but may not be formed.

Referring to FIG. 8, a channel layer 140 is formed on the light emitting structure layer 135 to correspond to a unit chip region.

The channel layer 140 may be formed on the second conductive semiconductor layer 130 using a mask pattern. The channel layer 140 may be formed using various deposition methods.

The channel layer 140 may be formed of a material having electrical conductivity lower than that of the reflective layer 160 or the bonding layer 170 or a material forming a Schottky contact with the second conductive semiconductor layer 130 . For example, the channel layer 140, ITO, IZO, IZTO, IAZO, IGZO, IGTO, AZO, ATO, ZnO, SiO _2, SiO _x, SiO _x N _y, Si ₃ N _4, Al ₂ O _3, TiO _x , TiO ₂ , Ti, Al, or Cr.

9 and 10, an ohmic contact layer 150 is formed on the second conductive semiconductor layer 130 and the channel layer 140. A reflective layer 160 (not shown) is formed on the ohmic contact layer 150, ) Can be formed.

The ohmic contact layer 150 and the reflective layer 160 may be formed by any one of E-beam deposition, sputtering, and PECVD (Plasma Enhanced Chemical Vapor Deposition), for example. .

The ohmic contact layer 150 and the reflective layer 160 may be formed in various areas and various kinds of light emitting devices may be formed depending on the area of the ohmic contact layer 150 and / Can be produced.

Referring to FIG. 11, a supporting substrate 180 is formed on the reflective layer 160 and the channel layer 140 via a bonding layer 170.

The bonding layer 170 is in contact with the reflective layer 160, the end of the ohmic contact layer 150 and the protective layer 140 to form the reflective layer 160, the ohmic contact layer 150, 140 can be strengthened.

The support substrate 180 is attached on the bonding layer 170. Although the supporting substrate 180 is bonded to the supporting substrate 180 through the bonding layer 170 in the embodiment, the supporting substrate 180 may be formed by a plating method or a vapor deposition method.

Referring to FIG. 12, the growth substrate 101 is removed from the light emitting structure layer 135. In Fig. 12, the light emitting device shown in Fig. 11 is shown in an inverted manner. Here, the growth substrate 101 may be removed by a laser lift off method or a chemical lift off method.

Referring to FIG. 13, isolation is performed on the light emitting structure layer 135 according to a unit chip region to separate the light emitting structure layers 135 into a plurality of light emitting structure layers 135.

For example, the isolation etching can be performed by a dry etching method such as ICP (Inductively Coupled Plasma).

14, a passivation layer 180 is formed on the channel layer 140 and the light emitting structure layer 135, and the passivation layer 180 is formed to expose the upper surface of the first conductive semiconductor layer 110 180 are selectively removed.

A roughness pattern 112 for improving light extraction efficiency is formed on the top surface of the first conductive semiconductor layer 110 and an electrode 115 is formed on the roughness pattern 112. Here, the roughness pattern 112 may be formed by a wet etching process or a dry etching process.

Then, a plurality of light emitting devices can be manufactured by separating the structure into unit chip regions through a chip separation process.

The chip separating process includes, for example, a braking process in which a physical force is applied and separated using a blade, a laser scribing process for separating chips by irradiating a laser to the chip boundary, a wet etching or a dry etching Etching processes, and the like, but the present invention is not limited thereto.

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

15, a light emitting device package 1000 includes a package body 30, a first electrode 31 and a second electrode 32 provided on the package body 30, And a molding member 40 surrounding the light emitting device 100. The light emitting device 100 includes a first electrode 31 and a second electrode 32. The light emitting device 100 is electrically connected to the first electrode 31 and the second electrode 32,

The package body 30 may include a silicon material, a synthetic resin material, or a metal material. The package body 30 may have a cavity having a sloped side surface.

The first electrode 31 and the second electrode 32 are electrically isolated from each other and provide power to the light emitting device 100. [ The first electrode 31 and the second electrode 32 may reflect light generated from the light emitting device 100 to increase the efficiency of light, It may also serve as a discharge.

The light emitting device 100 may be mounted on the package body 30 or on the first electrode 31 or the second electrode 32.

The light emitting device 100 may be electrically connected to the first electrode 31 and the second electrode 32 by wire, flip chip or die bonding. In the present embodiment, the light emitting device 100 is electrically connected to the first electrode 31 through the wire 50 and electrically connected to the second electrode 32 in direct contact therewith.

The molding member 40 may surround the light emitting device 100 to protect the light emitting device 100. In addition, the molding member 40 may include a phosphor to change the wavelength of light emitted from the light emitting device 100.

A light guide plate, a prism sheet, a diffusion sheet, a fluorescent sheet, and the like, which are optical members, may be disposed on a path of light emitted from the light emitting device package. The light emitting device package, the substrate, and the optical member may function as a backlight unit or function as a lighting unit. For example, the lighting system may include a backlight unit, a lighting unit, a pointing device, a lamp, and a streetlight.

16 is a view illustrating a backlight unit including the light emitting device or the light emitting device package according to the embodiment. However, the backlight unit 1100 in Fig. 16 is an example of the illumination system, and the invention is not limited thereto.

16, the backlight unit 1100 includes a bottom frame 1140, a light guide member 1120 disposed in the bottom frame 1140, at least one side surface of the light guide member 1120, And a light emitting module 1110 disposed in the light emitting module 1110. [ A reflective sheet 1130 may be disposed under the light guide member 1120.

The bottom frame 1140 may be formed in a box shape having an open upper surface to accommodate the light guide member 1120, the light emitting module 1110, and the reflection sheet 1130, Or a resin material, but the present invention is not limited thereto.

The light emitting module 1110 may include a substrate 700 and a plurality of light emitting device packages 600 mounted on the substrate 700. The plurality of light emitting device packages 600 may provide light to the light guide member 1120. In this embodiment, the light emitting device package 600 is mounted on the substrate 700, but the light emitting device 100 according to the embodiment may be installed directly.

As shown, the light emitting module 1110 may be disposed on at least one of the inner surfaces of the bottom frame 1140, thereby providing light toward at least one side of the light guide member 1120 can do.

The light emitting module 1110 may be disposed under the bottom frame 1140 and may provide light toward the bottom of the light guide member 1120 according to the design of the backlight unit 1100 The present invention is not limited thereto.

The light guide member 1120 may be disposed in the bottom frame 1140. The light guide member 1120 may guide the light provided from the light emitting module 1110 to a display panel (not shown) by converting the light into a surface light source.

The light guide member 1120 may be a light guide panel (LGP). The light guide plate may be formed of one of acrylic resin type such as PMMA (polymethyl methacrylate), polyethylene terephthlate (PET), polycarbonate (PC), COC and PEN (polyethylene naphthalate) resin.

An optical sheet 1150 may be disposed above the light guide member 1120.

The optical sheet 1150 may include at least one of a diffusion sheet, a light condensing sheet, a brightness increasing sheet, and a fluorescent sheet. For example, the optical sheet 1150 may be formed by laminating the diffusion sheet, the light condensing sheet, the brightness increasing sheet, and the fluorescent sheet. In this case, the diffusion sheet 1150 diffuses the light emitted from the light emitting module 1110 evenly, and the diffused light can be condensed by the condensing sheet into a display panel (not shown). At this time, the light emitted from the light condensing sheet is randomly polarized light, and the brightness increasing sheet can increase the degree of polarization of the light emitted from the light condensing sheet. The light condensing sheet may be a horizontal or / and a vertical prism sheet. In addition, the brightness enhancement sheet may be a dual brightness enhancement film. Further, the fluorescent sheet may be a translucent plate or film containing a phosphor.

The reflective sheet 1130 may be disposed under the light guide member 1120. The reflective sheet 1130 can reflect light emitted through the lower surface of the light guide member 1120 toward the light exit surface of the light guide member 1120.

The reflective sheet 1130 may be formed of a resin material having a high reflectance, that is, PET, PC, or PVC resin, but is not limited thereto.

17 is a view illustrating a lighting unit including a light emitting device or a light emitting device package according to the embodiment. However, the illumination unit 1200 of Fig. 17 is an example of the illumination system, and is not limited thereto.

17, the illumination unit 1200 includes a case body 1210, a light emitting module 1230 installed in the case body 1210, and a power supply unit And may include receiving connection terminals 1220.

The case body 1210 is preferably formed of a material having a good heat dissipation property, and may be formed of, for example, a metal material or a resin material.

The light emitting module 1230 may include a substrate 700 and at least one light emitting device package 600 mounted on the substrate 700. In the present embodiment, the light emitting device package 600 is installed on the substrate 700, but the light emitting device 100 according to the present embodiment may be installed directly.

The substrate 700 may be a circuit pattern printed on an insulator. For example, the PCB 700 may be a printed circuit board (PCB), a metal core PCB, a flexible PCB, a ceramic PCB . ≪ / RTI >

In addition, the substrate 700 may be formed of a material that efficiently reflects light, or may be formed of a color such that the surface is efficiently reflected to light, for example, white or silver.

The at least one light emitting device package 600 may be mounted on the substrate 700. The light emitting device package 600 may include at least one light emitting diode (LED). The light emitting diode may include a colored light emitting diode that emits red, green, blue, or white colored light, and a UV light emitting diode that emits ultraviolet (UV) light.

The light emitting module 1230 may be arranged to have various combinations of light emitting diodes to obtain color and brightness. For example, a white light emitting diode, a red light emitting diode, and a green light emitting diode may be arranged in combination to secure a high color rendering index (CRI). Further, a fluorescent sheet may be further disposed on the path of light emitted from the light emitting module 1230, and the fluorescent sheet may change the wavelength of light emitted from the light emitting module 1230. For example, when the light emitted from the light emitting module 1230 has a blue wavelength band, the fluorescent sheet may include a yellow phosphor. Light emitted from the light emitting module 1230 passes through the fluorescent sheet, .

The connection terminal 1220 may be electrically connected to the light emitting module 1230 to supply power. As shown in FIG. 14, the connection terminal 1220 is connected to the external power source in a socket manner, but is not limited thereto. For example, the connection terminal 1220 may be formed in a pin shape and inserted into an external power source, or may be connected to an external power source through a wire.

In the above-described illumination system, at least one of a light guide member, a diffusion sheet, a light condensing sheet, a brightness increasing sheet, and a fluorescent sheet is disposed on the path of light emitted from the light emitting module to obtain a desired optical effect.

As described above, the illumination system can have excellent light efficiency and reliability by including the light emitting device or the light emitting device package with reduced operating voltage and improved light efficiency.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by equivalents to the appended claims, as well as the appended claims.

Claims (11)

A support substrate;
A light emitting structure layer including a first conductive semiconductor layer, a second conductive semiconductor layer, and an active layer between the first conductive semiconductor layer and the second conductive semiconductor layer on the supporting substrate; And
A first pad portion and a second pad portion disposed closer to the outermost portion from the center region of the upper surface of the light emitting structure layer and an external electrode extending from at least one of the first pad portion and the second pad portion, ,
The first pad portion is disposed on a first region closer to the outermost portion than a center region of the upper surface of the light emitting structure layer,
Wherein the second pad portion includes a first line segment extending from the first region along a first side of the upper surface of the light emitting structure layer and a second line segment connecting the first region and the opposite side of the first region, The second region being spaced apart from the first region,
The external electrode
A third external electrode extending in a second direction orthogonal to the first direction and connecting the first external electrode and the second external electrode and a third external electrode extending in a second direction perpendicular to the first direction, And an external electrode,
Wherein the first pad portion is disposed at a position where the second external electrode disposed in the first direction and the third external electrode disposed in the second direction meet,
Wherein the second pad portion is disposed on a first external electrode that is not adjacent to the first pad portion and is disposed in an area having a distance ratio X corresponding to the following equation.
[Mathematical Expression]

, Where A is the length of the first external electrode, B is the length of the third external electrode, C is the length from the third external electrode to the second pad portion located on the first external electrode, And the third external electrode. A support substrate;
A light emitting structure layer including a first conductive semiconductor layer, a second conductive semiconductor layer, and an active layer between the first conductive semiconductor layer and the second conductive semiconductor layer on the supporting substrate;
A first pad portion and a second pad portion disposed closer to the outermost portion from the center region of the upper surface of the light emitting structure layer and an external electrode extending from at least one of the first pad portion and the second pad portion, ,
The first pad portion is disposed on a first region closer to the outermost portion than a center region of the upper surface of the light emitting structure layer,
The second pad portion may include a first line segment extending from the first region along the first side of the upper surface of the light emitting structure layer and a second line segment connecting the first region and the opposite side of the first region at an angle of at least 10 degrees The second region being spaced apart from the first region,
The external electrode
A third external electrode extending in a second direction orthogonal to the first direction and connecting the first external electrode and the second external electrode and a third external electrode extending in a second direction perpendicular to the first direction, And an external electrode,
Wherein the first pad portion is disposed at a position where the second external electrode disposed in the first direction and the third external electrode disposed in the second direction meet,
Wherein the second pad portion is disposed on a fourth external electrode that is not adjacent to the first pad portion and is disposed in a region having a distance ratio Y corresponding to the following equation.
[Mathematical Expression]

, Where A is the length of the second external electrode, B is the length of the fourth external electrode, D is the length from the second external electrode to the second pad portion 115c2 located on the fourth external electrode, 1 is the angle between the line segment connecting the pad portion and the second pad portion and the second external electrode. 3. The method according to claim 1 or 2,
And an internal electrode disposed in a region surrounded by the external electrode. The method of claim 3,
Wherein a width of at least a portion of the external electrode is greater than a width of the internal electrode. 3. The method according to claim 1 or 2,
Wherein a width of the external electrode extending outward with respect to the first pad portion and the second pad portion is thinner as the distance from the first pad portion and the second pad portion is reduced. The method of claim 3,
The internal electrode
And a first internal electrode and a second internal electrode that connect the first external electrode and the second external electrode. delete delete delete delete delete

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