TWM522468U - Light emitting device - Google Patents

Description

Light-emitting element

The present invention relates to a light-emitting element, and more particularly to a light-emitting element comprising an electrode which can improve the thermal, electrical and luminescent properties of the light-emitting element.

Recently, as the demand for small-sized and high-power light-emitting elements has increased, the demand for large-area flip chip type light-emitting elements having excellent heat dissipation efficiency has increased. The electrode of the flip chip type light-emitting element is directly bonded to the secondary substrate, and the wire for supplying the external power source is not used in the flip chip type light-emitting element, so that the heat dissipation efficiency is very high compared with the horizontal light-emitting element. . Therefore, even if a high-density current is applied, heat can be efficiently transferred to the secondary substrate side, so that the flip-chip type light-emitting element is suitable as a high-power light-emitting source.

In addition, in order to achieve miniaturization of a light-emitting element, there is an increasing demand for a chip-scale package which omits a process of packaging a light-emitting element to an extra-housing housing. The light-emitting element itself is used as a package. The electrode of the flip chip type light-emitting element can function similarly to the lead of the package, and therefore, a flip-chip type light-emitting element can be usefully used in such a wafer-level package.

In the case where such a wafer-level package-formed element is used as a high-power light-emitting device, a high-density current is applied to the wafer-level package. In this case, when the high-power wafer-level package is driven, a phenomenon in which current concentrates in the region where the N-type electrode is formed occurs. Therefore, the light emission of the wafer-level package is concentrated to the region where the N-type electrode is formed, and in addition, the heat generation of this portion is also severe. As described above, in a specific region of the light-emitting element, light is emitted and heat is concentrated, and the light emission is uneven, and the heat radiation efficiency of the light-emitting element is lowered to adversely affect the reliability and life of the light-emitting element.

[Questions to be solved by new creations]

An object of the present invention is to provide a light-emitting element which has uniform light-emitting characteristics as a whole and which is excellent in heat dissipation efficiency. [Means for solving the problem]

The light-emitting element of one aspect of the present invention includes: a light-emitting structure including a first conductive semiconductor layer, a second conductive semiconductor layer, and between the first conductive semiconductor layer and the second conductive semiconductor layer The active layer; the first contact electrode and the second contact electrode are located on the light emitting structure, and are in ohmic contact with the first conductive type semiconductor layer and the second conductive type semiconductor layer; The first insulating portion and the second insulating portion partially cover the first contact electrode and the second contact electrode; the first electrode and the second electrode are located on the light emitting structure, and are electrically connected to the first contact respectively An electrode and a second contact electrode; a third insulating portion covering a side surface of the first electrode and the second electrode; a connection layer on the first electrode, the second electrode, and the third insulating portion; and the first a pad electrode and a second pad electrode are disposed on the connection layer; and the first pad electrode and the second pad electrode are electrically connected to the first through the connection layer The first electrode and the second electrode, the horizontal area of the first pad electrode is smaller than the horizontal area of the first electrode, and the horizontal area of the second pad electrode is larger than the horizontal area of the second electrode.

Thereby, the heat dissipation efficiency of the light-emitting element is improved, reliability and life can be improved, and a light-emitting element having uniform light-emitting characteristics can be provided.

The first electrode may be located on a portion of the first contact electrode that is in ohmic contact with the first conductive type semiconductor layer.

In addition, a portion of the first contact electrode that is in ohmic contact with the first conductive type semiconductor layer may not be located below the second electrode.

The first contact electrode may include a plurality of ohmic contact regions in contact with the first conductive type semiconductor layer to achieve ohmic contact, and the first electrode may be in contact with the plurality of ohmic contact regions of the first contact electrode All contact.

Additionally, the first contact electrode may include a plurality of ohmic contact regions in contact with the first conductive type semiconductor layer to achieve ohmic contact, and only a portion of the plurality of ohmic contact regions may be in contact with the first electrode.

Further, the light emitting element may further include: a first wiring layer located under the first electrode; and a second wiring layer located under the second electrode; and a portion of the first wiring layer A first contact electrode may be in contact, and a portion of the second wiring layer may be in contact with the second contact electrode.

A portion of the second insulating portion may be located between the first wiring layer and the first contact electrode.

The horizontal cross-sectional area of the first electrode may be 0.8 times or more and less than 1 time of a sum of horizontal cross-sectional areas of the first electrode and the second electrode.

In addition, the horizontal area of the first pad electrode and the horizontal area of the second pad electrode may be the same.

The connection layer may include an insulating material layer; a first connection layer electrically connecting the first electrode to the first pad electrode and penetrating the insulating material layer; and a second connection layer The second electrode is electrically connected to the second pad electrode and penetrates the insulating material layer.

The second electrode may be formed in plurality, and the second electrode may be electrically connected to the second pad electrode.

Further, the first contact electrode may include a plurality of ohmic contact regions in contact with the first conductive type semiconductor layer to achieve ohmic contact, and a portion of the plurality of ohmic contact regions may be disposed to the second electrode between.

The first electrode and the second electrode may respectively include metal particles and a non-metallic substance interposed between the metal particles.

Further, the metal particles and the non-metallic substance may be formed into a sintered form of a metal particle.

The first electrode and the second electrode may each include an inclined side surface, and the inclined side surface may include a side surface in which a tangential inclination of each of the first electrode and the second electrode changes.

In addition, the first electrode and the second electrode may respectively contain 80 to 98 wt% of metal particles.

In some embodiments, the light emitting structure of the light emitting element may further include an area in which the active layer and the second conductive type semiconductor layer are partially removed to partially expose the first conductive type semiconductor layer The first contact electrode may be in ohmic contact with the first conductive type semiconductor layer by partially exposing a region of the first conductive type semiconductor layer.

Further, a region where the first conductive semiconductor layer is partially exposed may be formed in a plurality of hole forms.

Furthermore, the second contact electrode may be located on the second conductive semiconductor layer, and the first insulating portion may cover the second contact electrode and the light emitting structure, and may include a first opening portion and a second opening portion. The first opening portion and the second opening portion respectively expose a portion of the region where the first conductive type semiconductor layer is exposed and a portion of the second contact electrode, and the first contact electrode at least partially covers the first portion An insulating portion may be in contact with the first conductive type semiconductor layer through the first opening portion, the second insulating portion partially covering the first contact electrode, and may include a third opening portion and a fourth opening The third opening portion partially exposes the first contact electrode, and the fourth opening portion is disposed corresponding to a position of the second opening portion to expose a portion of the second contact electrode.

The first electrode may be in contact with the first contact electrode through the third opening portion, and the second electrode may be in contact with the second contact electrode through the fourth opening portion, the plurality of The holes may be located below the third opening portion area. [New creative effect]

According to the novel creation, the first electrode having a horizontal cross-sectional area larger than that of the second electrode is included, whereby the heat dissipation efficiency of the light-emitting element is improved, thereby improving reliability and life. In addition, it is possible to provide a light-emitting element in which the ratio of the area occupied by the first electrode in the light-emitting element is increased and the light-emitting element has uniform light-emitting characteristics as a whole.

Hereinafter, an embodiment of the present novel creation will be described in detail with reference to the accompanying drawings. The embodiments described below are provided to provide exemplary embodiments for the purpose of fully conveying the inventive concept to those of ordinary skill in the art. Therefore, the present invention is not limited to the embodiments described below, and may be embodied in other forms. Further, in the drawings, the width, length, thickness, and the like of the constituent elements may be exaggerated for convenience of explanation. In addition, when it is described that one component is "upper" or "upper" of another component, not only the case where each part is "directly above" or "directly above" but also included A case where another component is interposed between the component and the other component. Throughout the specification, the same reference numerals denote the same constituent elements.

1(a), 1(b) and 2 are a plan view and a cross-sectional view for explaining a light-emitting element of an embodiment of the present invention.

1(a) is a plan view of the light-emitting element 100a, and FIG. 1(b) is a plan view for explaining the position of the hole 120h and the positions of the third opening 153a and the fourth opening 153b, and FIG. 2 is a view similar to FIG. a) A cross-sectional view of a cross section of a region corresponding to the AA line of Fig. 1(b).

1(a), 1(b) and 2, the light emitting device 100a may include a light emitting structure 120 including a first conductive semiconductor layer 121, an active layer 123, and a second conductive semiconductor layer 125; a contact electrode 130; a second contact electrode 140; a first insulating portion 151 and a second insulating portion 153; a first electrode 161; a second electrode 163; and a third insulating portion 170. Further, the light-emitting element 100a may further include a first pad electrode and a second pad electrode (not shown), a growth substrate (not shown), and a wavelength conversion portion (not shown).

The light emitting structure 120 may include: a first conductive type semiconductor layer 121; an active layer 123 on the first conductive type semiconductor layer 121; and a second conductive type semiconductor layer 125 on the active layer 123. The first conductive semiconductor layer 121, the active layer 123, and the second conductive semiconductor layer 125 may include a group III-V compound semiconductor, and for example, may include a nitride-based semiconductor such as (Al, Ga, In)N. The first conductive type semiconductor layer 121 may include an n-type impurity (for example, Si), and the second conductive type semiconductor layer 125 may include a p-type impurity (for example, Mg). Alternatively, it can be reversed. The active layer 123 may comprise a multiple quantum well structure (MQW).

In addition, the light emitting structure 120 may include a region in which the second conductive semiconductor layer 125 and the active layer 123 are partially removed to partially expose the first conductive semiconductor layer 121. For example, as shown in the figure, the light emitting structure 120 may include at least one hole 120h that penetrates the second conductive semiconductor layer 125 and the active layer 123 to expose the first conductive semiconductor layer 121.

The holes 120h may be formed in plurality, and the plurality of holes 120h may be arranged substantially regularly. For example, as shown in FIG. 1(a) and FIG. 1(b), the holes 120h can be arranged in a fixed pattern at regular intervals. The holes 120h are regularly arranged across the entire light-emitting structure, whereby the current can be uniformly dispersed in the horizontal direction when the light-emitting element 100a is driven. However, the present invention is not limited to this, and the configuration and the number of the holes 120h can be variously modified.

Further, the form in which the first conductive semiconductor layer 121 is exposed is not limited to the form of the hole 120h. For example, a region in which the first conductive semiconductor layer 121 is exposed may be formed in a line form, a form in which a hole and a line are combined, and the like. In a case where a region in which the first conductive semiconductor layer 121 is exposed is formed in a plurality of line forms, the light emitting structure 120 may further include one or more mesa formed along the line and including the active layer 123 And a second conductive semiconductor layer 125. Therefore, in the present embodiment, the novel creation is described on the basis of the light-emitting structure 120 including the plurality of holes 120h, but the present invention is not limited thereto.

The light emitting structure 120 may further include a rough surface 120R formed on a lower surface thereof. The rough surface 120R may be formed by at least one of wet etching, dry etching, and electrochemical etching. For example, a rough surface 120R may be formed by photoelectrochemical (PEC) etching or an etching method using an etching solution containing KOH and NaOH. . The protrusions and/or depressions of the μm to nm level formed on the surface of the first conductive type semiconductor layer 121 may be included due to the formation of the rough surface 120R. By forming a rough surface on the surface of the light-emitting structure 120, the extraction efficiency of the light-emitting element can be improved.

In addition, the light emitting structure 120 may further include a growth substrate (not shown) located below the first conductive semiconductor layer 121. The growth substrate is not limited as long as it is a substrate that can grow the light-emitting structure 120. For example, the growth substrate may be a sapphire substrate, a silicon carbide substrate, a silicon substrate, a gallium nitride substrate, an aluminum nitride substrate, or the like. Such a growth substrate can be separated and removed from the light-emitting structure 120 by a known technique.

The second contact electrode 140 is located on the second conductive type semiconductor layer 125. The second contact electrode 140 at least partially covers the upper surface of the second conductive type semiconductor layer 125 and is in ohmic contact with the second conductive type semiconductor layer 125. Further, the second contact electrode 140 can be disposed to cover the entire upper surface of the second conductive semiconductor layer 125. In other words, it is possible to cover the upper surface of the second conductive semiconductor layer 125 with a single body except for the remaining region except the position where the hole 120h is formed in the light emitting structure 120. Thereby, a current can be uniformly supplied to the entire light-emitting structure 120 to improve the current dispersion efficiency.

However, the present invention is not limited thereto, and the second contact electrode 140 may not be integrally formed, and a plurality of unit reflective electrode layers spaced apart from each other may be disposed on the upper surface of the second conductive semiconductor layer 125. In this case, the unit reflective electrode layers may be electrically connected to each other through a specific connection portion.

The second contact electrode 140 may include a substance that can be in ohmic contact with the second conductive type semiconductor layer 125, and may include, for example, a metal substance and/or a conductive oxide.

In the case where the second contact electrode 140 includes a metal substance, the second contact electrode 140 may include a reflective layer and a cover layer covering the reflective layer. As described above, the second contact electrode 140 is in ohmic contact with the second conductive type semiconductor layer 125, and at the same time functions as a reflected light. Therefore, the reflective layer has a higher reflectance and may include a metal that can form an ohmic contact with the second conductive type semiconductor layer 125. For example, the reflective layer may include at least one of Ni, Pt, Pd, Rh, W, Ti, Al, Mg, Ag, and Au. Additionally, the reflective layer may comprise a single layer or multiple layers.

The cover layer prevents interdiffusion between the reflective layer and other substances, and prevents other external substances from diffusing to the reflective layer to destroy the reflective layer. Therefore, the cover layer can be formed to cover the lower surface and the side surface of the reflective layer. The cover layer may be electrically connected to the second conductive type semiconductor layer 125 together with the reflective layer, and thus may function as an electrode together with the reflective layer. The cover layer may, for example, comprise Au, Ni, Ti, Cr, etc., and may also comprise a single layer or multiple layers.

On the other hand, in the case where the second contact electrode 140 includes a conductive oxide, the conductive oxide may be indium tin oxide (ITO), zinc oxide (Zinc Oxid, ZnO), or aluminum zinc oxide. (Aluminum Zinc Oxide, AZO), Indium Zinc Oxide (IZO), and the like. In the case where the second contact electrode 140 includes a conductive oxide, the upper surface of the second conductive type semiconductor layer 125 in a wider area can be covered than in the case of containing a metal. That is, in the case where the second contact electrode 140 is formed of a conductive oxide, the separation distance from the upper edge of the hole 120h to the second contact electrode 140 can be formed relatively shorter. In this case, the shortest distance from the portion where the second contact electrode 140 is in contact with the second conductive type semiconductor layer 125 to the portion where the first contact electrode 130 is in contact with the first conductive type semiconductor layer 121 can be relatively shorter. Therefore, the forward voltage (Vf) of the light-emitting element 100a can be reduced.

The first insulating portion 151 and the second insulating portion 153 may partially cover the first contact electrode 130 and the second contact electrode 140. Hereinafter, the first insulating portion 151 will be described first, and then the content related to the second insulating portion 153 will be described.

The first insulating portion 151 may partially cover the upper surface of the light emitting structure 120 and the second contact electrode 140. Further, the first insulating portion 151 covers the side faces of the plurality of holes 120h, but the first conductive type semiconductor layer 121 exposed by the holes 120h may be partially exposed.

Further, the first insulating portion 151 may also cover a side surface of at least a portion of the light emitting structure 120. The extent to which the first insulating portion 151 covers the side surface of the light emitting structure 120 may differ depending on whether or not wafer unit singulation occurs in the manufacturing process of the light emitting element. That is, as in the present embodiment, the first insulating portion 151 can also be formed to cover only the upper surface of the light emitting structure 120, and in the manufacturing process of the light emitting element 100a, after the wafer is singulated into wafer units In the case where the first insulating portion 151 is formed, the first insulating portion 151 may be covered to the side surface of the light emitting structure 120.

The first insulating portion 151 may include a first opening portion located at a portion corresponding to the plurality of holes 120h, and a second opening portion exposing a portion of the second contact electrode 140. The first conductive semiconductor layer 121 may be partially exposed through the first opening and the hole 120h, and the second contact electrode 140 may be partially exposed through the second opening.

At this time, the first opening portion and the second opening portion can be arranged in a fixed pattern. For example, as shown in FIG. 1(a) and FIG. 1(b), the second opening portion may be disposed adjacent to one side surface of the light-emitting element 100a, and the first opening portion may be regularly arranged to be unconfigured. The area of the two openings.

The first insulating portion 151 may include an insulating substance, and may include, for example, SiO ₂ , SiN _x , MgF _{2 ,} or the like. Further, the first insulating portion 151 may include a plurality of layers, and may further include a distributed bragg reflector in which substances having different refractive indices are alternately laminated. In particular, in the case where the second contact electrode 140 includes a conductive oxide, the first insulating portion 151 includes a distributed Bragg reflector to improve the light-emitting efficiency of the light-emitting element 100a.

The first contact electrode 130 may partially cover the light emitting structure 120 and may be in ohmic contact with the first conductive type semiconductor layer 121 through the plurality of holes 120h and the first opening. Therefore, the first contact electrode 130 may include an ohmic contact region 131 that is in direct contact with the first conductive type semiconductor layer 121 to achieve ohmic contact. When the light-emitting structure 120 includes a plurality of holes 120h, the ohmic contact regions 131 may be formed in plural numbers corresponding to the number of the holes 120h.

The first contact electrode 130 can be formed to cover the entire portion of the first insulating portion 151 excluding a part of the region. In addition, the first contact electrode 130 can also be formed to cover the side surface of the light emitting structure 120. In the case where the first contact electrode 130 is also formed to the side surface of the light emitting structure 120, light emitted from the active layer 123 to the side surface can be reflected upward to increase the ratio of light emitted from the upper surface of the light emitting element 100a. On the other hand, the first contact electrode 130 is not formed in a region corresponding to the second opening portion of the first insulating portion 151, and is insulated from the second contact electrode 140.

The first contact electrode 130 is formed to cover the entire upper surface of the light emitting structure 120 except for a part of the region, whereby the current dispersion efficiency can be further improved. In addition, the portion not covered by the second contact electrode 140 may be covered by the first contact electrode 130, so that light can be more efficiently reflected to improve the light-emitting efficiency of the light-emitting element 100a.

The first contact electrode 130 is in ohmic contact with the first conductive semiconductor layer 121 and functions as a reflected light. Therefore, the first contact electrode 130 may be composed of a single layer or a plurality of layers, and may include a highly reflective metal layer such as an Al layer. The highly reflective metal layer may be formed on an adhesion layer such as Ti, Cr or Ni. However, the novel creation is not limited thereto, and the first contact electrode 130 may further include at least one of Ni, Pt, Pd, Rh, W, Ti, Al, Mg, Ag, and Au.

The first contact electrode 130 is in ohmic contact with the first conductive type semiconductor layer 121 through the hole 120h, and thus the region where the active layer 123 is removed in order to form an electrode or the like connected to the first conductive type semiconductor layer 121 corresponds to the plurality of holes 120h. The area is the same. Therefore, a region for achieving ohmic contact of the first conductive type semiconductor layer 121 with the metal layer can be minimized, and a light emitting element having a relatively large ratio of the area of the light emitting region to the horizontal area of the entire light emitting structure can be provided.

The second insulating portion 153 may partially cover the first contact electrode 130. In addition, the second insulating portion 153 may include a third opening portion 153a that partially exposes the first contact electrode 130, and a fourth opening portion 153b that partially exposes the second contact electrode 140. At this time, the fourth opening portion 153b can be formed to a position corresponding to the second opening portion.

One or more of the third opening portion 153a and the fourth opening portion 153b may be formed separately. Further, as shown in FIG. 1(b), the fourth opening portion 153b can be positioned adjacent to one corner of the light-emitting element 100a, and the third opening portion 153a can be formed such that at least a part of the holes 120h are formed. The position is exposed in a way that is formed. Further, the third opening portion 153a can be formed to expose a position where all the holes 120h are formed. Thereby, the ohmic contact region 131 can be exposed through the third opening portion 153a.

The second insulating portion 153 may include an insulating substance, and may include, for example, SiO ₂ , SiN _x , MgF ₂ . Further, the second insulating portion 153 may include a plurality of layers, and may further include a distributed Bragg reflector in which substances having different refractive indices are alternately laminated.

The first electrode 161 and the second electrode 163 may be located on the light emitting structure 120, and the first electrode 161 and the second electrode 163 may be electrically connected to the first contact electrode 130 and the second contact electrode 140, respectively. In particular, the first electrode 161 and the second electrode 163 can be in direct contact with the first contact electrode 130 and the second contact electrode 140 to achieve electrical connection.

In addition, at least a portion of the holes 120h may be located below the first electrode 161, and further, all of the holes 120h may be located below the first electrode 161. Therefore, the ohmic contact region 131 of the first contact electrode 130 may be interposed between the first electrode 161 and the first conductive type semiconductor layer 121, and in addition, all the ohmic contact regions 131 may be in direct contact with the first electrode 161.

On the other hand, the hole 120h may not be located below the second electrode 163. That is, a portion where the first contact electrode 130 is in ohmic contact with the first conductive type semiconductor layer 121 may not be located below a region where the second electrode 163 is formed. Therefore, as shown in FIGS. 1(a) and 1(b), the hole 120h of the light-emitting structure 120 can be formed only to the remaining portion of the light-emitting element 100a except for a region adjacent to one side.

The first electrode 161 and the second electrode 163 may have different volumes from each other, and the volume of the first electrode 161 may be larger than the volume of the second electrode 163. In addition, the thickness of the first electrode 161 and the second electrode 163 may be formed to be about 70 μm to 80 μm or more, and may be formed to be substantially the same thickness. Therefore, the horizontal cross-sectional area of the first electrode 161 may be greater than the horizontal cross-sectional area of the second electrode 163. For example, the horizontal cross-sectional area of the first electrode 161 may have a horizontal cross-sectional area of the first electrode 161 and the second electrode 163. The value is 0.8 times or more and less than 1 time.

That is, the light-emitting element 100a includes the first electrode 161 having a horizontal cross-sectional area that is very large compared to the horizontal cross-sectional area of the second electrode 163. When the first conductive semiconductor layer 121 is an N-type semiconductor layer, the first electrode 161 can function as an N-type electrode. As described above, when the light-emitting element 100a is driven, light emission and heat generation are concentrated in positioning. The area of an electrode 161. Therefore, by forming the horizontal cross-sectional area of the first electrode 161 in a manner significantly larger than the horizontal cross-sectional area of the second electrode 163 as in the present embodiment, the light emission can be made uniform in the entire light-emitting region of the light-emitting element 100a to improve the light-emitting characteristics. The heat dissipation efficiency of the light-emitting element 100a can be improved by effectively dissipating heat through the first electrode 161.

Moreover, the first electrode 161 is in direct contact with the first contact electrode 130, and thus may also be in direct contact with the ohmic contact region 131 of the first contact electrode 130. At this time, the ohmic contact region 131 corresponds to the position of the plurality of holes 120h, and the holes 120h are substantially regularly arranged to the entire light-emitting structure 120. Thereby, the current can be uniformly dispersed in the horizontal direction to improve the electrical characteristics of the light-emitting element 100a, and the heat generated by the light-emitting structure 120 can be effectively released to the outside through the ohmic contact region 131 and the first electrode 161.

Moreover, a portion where the first contact electrode 130 is not in ohmic contact with the first conductive type semiconductor layer 121 is located below a region where the second electrode 163 is formed, so that the first conductive type semiconductor layer 121 and the first contact electrode 130 can be made ohmic. The heat generated by the contact portion is all released through the first electrode 161. Therefore, the heat dissipation efficiency of the light emitting element 100a can be further improved.

As described above, according to the present invention, the light-emitting efficiency and the heat-dissipation efficiency of the light-emitting element 100a are improved, and reliability and life can be improved.

On the other hand, the first electrode 161 and the second electrode 163 may include metal particles and a non-metallic substance interposed between the metal particles. Further, each of the first electrode 161 and the second electrode 163 may include a sintered metal particle, and the sintered metal particle includes the metal particle and a non-metallic substance. In the sintered body of the metal particles, a form in which a plurality of particles are arranged by sintering the metal particles can be formed, and a non-metallic substance can be interposed in at least a part of the regions between the metal particles. Such a non-metallic substance acts to buffer the buffer which can generate stress in the first electrode 161 and the second electrode 163. Thereby, the mechanical stability of the first electrode 161 and the second electrode 163 is improved, and the stress that can be applied from the first electrode 161 and the second electrode 163 to the light-emitting structure 120 can be reduced.

The first electrode 161 and the second electrode 163 may respectively contain metal particles in a ratio of 80 wt% to 98 wt% with respect to the mass of each of the first electrode 161 and the second electrode 163, respectively. The first electrode 161 and the second electrode 163 include the metal particles of the above ratio, thereby having excellent thermal conductivity and electrical conductivity, and can effectively buffer stress generated in the first electrode 161 and the second electrode 163 to improve the first Mechanical stability of the electrode 161 and the second electrode 163.

The metal particles are not particularly limited as long as they have thermal conductivity and electrical conductivity, and may include, for example, Cu, Au, Ag, Pt, or the like. The non-metallic substance may be derived from a substance to be a sintered object for forming an electrode, and may be, for example, a polymer material containing C.

In the above embodiment, the metal particles are described as being in the form of a sintered metal particle and are included in the first electrode 161 and the second electrode 163. However, the present invention is not limited thereto. Unlike this, the first electrode 161 and the second electrode 163 can also be formed by vapor deposition and/or plating of a metal. In this case, the first electrode 161 and the second electrode 163 may be composed of a plurality of layers.

In the present embodiment, the first electrode 161 and the second electrode 163 may have side faces that are substantially perpendicular to the upper surface of the second insulating portion 153. However, the creation of the present invention is not limited thereto, and as shown in FIG. 3, the first electrode 261 and the second electrode 263 may each have an inclined side surface.

3 is a cross-sectional view showing a light-emitting element 100b according to another embodiment of the present invention, and the first electrode 261 and the first electrode 261 are compared with the light-emitting element 100a of FIGS. 1(a), 1(b) and 2; The two electrodes 263 have inclined sides.

Referring to FIG. 3, the first electrode 261 and the second electrode 263 may respectively include inclined sides. In particular, as shown in FIG. 3, the first electrode 261 and the second electrode 263 may respectively include inclined side faces whose inclination of the tangent TL of the side surface of the vertical cross section changes. Specifically, the inclination of the tangent TL of the side surface of the vertical cross section of each of the first electrode 261 and the second electrode 263 increases in the direction from the lower portion to the upper portion, and then increases again via the specific inflection point. Therefore, the inclined side faces of the first electrode 261 and the second electrode 263 may include a region where the inclination of the tangent TL increases and a region where the inclination of the tangent TL decreases.

Each of the first electrode 261 and the second electrode 263 includes an inclined side surface whose inclination of the tangent TL of the side surface of the vertical cross section changes, whereby the horizontal cross-sectional area of each of the first electrode 261 and the second electrode 263 can occur in the up and down direction Variety. For example, as shown in the drawing, the horizontal cross-sectional area of each of the first electrode 261 and the second electrode 263 may become smaller toward the upper surface of the light emitting structure 120.

Therefore, the first electrode 261 and the second electrode 263 can each have a shape that has the side surface of the above-described configuration, and can be formed, for example, in a form similar to a truncated arch. The first electrode 261 and the second electrode 263 include a slanted side surface whose inclination of the tangential line TL of the side surface of the vertical cross section is changed, so that the interface between the first electrode 261 and the second electrode 263 and the third insulating portion 170 can be improved. stability.

Referring again to FIGS. 1(a), 1(b) and 2, the first electrode 161 and the second electrode 163 may be in direct contact with the first contact electrode 130 and the second contact electrode 140, respectively. That is, the first electrode 161 and the second electrode 163 may be formed to directly contact the first contact electrode and the second contact electrode, respectively, so that in the case of using the plating method, the necessary seed layer may be omitted ( In the case of additionally adding a seed layer or in the case of using a solder, it is possible to omit an extra structure which is added as necessary for wetting. However, the novel creation is not limited to this.

On the other hand, the shortest distance among the spaces between the first electrode 161 and the second electrode 163 may be about 10 μm to 80 μm. Thereby, it is possible to prevent the interval between the electrodes from being widened, and the forward voltage (Vf) of the light-emitting element 100a is increased, and the horizontal cross-sectional area of the first electrode 161 and the second electrode 163 can be increased to reduce the interval between the electrodes. Thereby, the heat dissipation efficiency of the light emitting element 100a can be improved.

The third insulating portion 170 can be formed on the light emitting structure 120 so as to at least partially cover the side surfaces of the first electrode 161 and the second electrode 163. The first electrode 161 and the second electrode 163 are exposed on the upper surface of the third insulating portion 170.

The third insulating portion 170 is electrically insulating and covers the side faces of the first electrode 161 and the second electrode 163 to effectively insulate each other. At the same time, the third insulating portion 170 can function to support the first electrode 161 and the second electrode 163. The upper surface of the third insulating portion 170 may be formed in parallel at substantially the same height as the upper surfaces of the first electrode 161 and the second electrode 163.

The third insulating portion 170 may include an insulating polymer and/or an insulating ceramic, and may include, for example, an Epoxy Molding Compound (EMC) or a Si resin. In addition, the third insulating portion 170 may further contain light reflectivity and light scattering particles such as TiO ₂ particles.

Further, unlike the drawing, the third insulating portion 170 may cover the side surface of the light emitting structure 120. In this case, the light emission angle of the light emitted from the light emitting structure 120 may be different. For example, when the third insulating portion 170 further covers at least a part of the side surface of the light emitting structure 120, a part of the light emitted to the side surface of the light emitting structure 120 can be reflected to the lower surface of the light emitting structure 120. As described above, by adjusting the area in which the third insulating portion 170 is disposed, the light-emitting angle of the light-emitting element 100a can be adjusted.

Further, the light emitting element 100a may further include a first pad electrode (not shown) and a second pad electrode (not shown). The first pad electrode and the second pad electrode may be located on the third insulating portion 170 and may be in electrical contact with the first electrode 161 and the second electrode 163, respectively.

When the light-emitting element 100a is applied to a module or the like, the first pad electrode and the second pad electrode can stably mount the light-emitting element 100a to an extra-added substrate or the like. For example, when the first electrode 161 and the second electrode 163 include a sintered body of Cu or Ag particles, the wettability of the first electrode 161 and the second electrode 163 to solder or the like is not good. Therefore, by arranging the first pad electrode and the second pad electrode on the third insulating portion 170, the light-emitting element 100a can be stably mounted.

The first electrode pad and the second electrode pad may comprise a conductive substance such as a metal, and may include, for example, Ni, Pt, Pd, Rh, W, Ti, Al, Ag, Sn, Cu, Ag, Bi, In, Zn, Sb. , Mg, Pb, etc. In addition, the first electrode pad and the second electrode pad may be composed of a single layer or a plurality of layers, respectively.

The wavelength conversion portion may be located on a lower surface of the light emitting structure 120.

The wavelength converting portion converts the wavelength of the light emitted from the light emitting structure 120 to emit light of a wavelength band required for the light emitting element. The wavelength conversion unit may include a phosphor and a carrier that carries the phosphor. The phosphor may comprise various phosphors well known to those skilled in the art, and may comprise a garnet type phosphor, an aluminate phosphor, a sulfide phosphor, an oxynitride. At least one of a phosphor, a nitride phosphor, a fluoride-based phosphor, and a phthalate phosphor. The carrier may also be a material well known to those skilled in the art, for example, a polymer resin such as an epoxy resin or an acrylic resin, or a ruthenium resin. Further, the wavelength converting portion may be composed of a single layer or a plurality of layers.

The wavelength conversion portion may cover the lower surface of the light emitting structure 120, and may cover the side surface of the light emitting structure 120, and may be formed to cover the side surface of the third insulating portion 170.

In the present embodiment, the light-emitting element 100a having the light-emitting structure 120 including the plurality of holes 120h has been described, but the present invention is not limited thereto. The light-emitting structure 120, the first contact electrode 130 and the second contact electrode 140, the first insulating portion 151, and the second insulating portion 153 can be variously combined with each other, and the deformed light-emitting element is also included in Within the scope of this new creation.

4(a), 4(b) and 5 are a plan view and a cross-sectional view for explaining a light-emitting element of another embodiment of the present invention.

The light-emitting element 100c of the embodiment of FIGS. 4(a), 4(b) and 5 is substantially similar to the light-emitting element 100a of FIGS. 1(a), 1(b) and 2, but at the third opening portion 153a. There is a difference, and there is a difference in that the first wiring layer 181 and the second wiring layer 183 are further included. Hereinafter, the light-emitting element 100c of the present embodiment will be described focusing on the difference point, and the same configuration will not be described in detail.

4(a) is a plan view of the light-emitting element 100c, and FIG. 4(b) is a plan view for explaining the position of the hole 120h and the positions of the third opening 153a and the fourth opening 153b, and FIG. 5 is a view similar to FIG. a) A cross-sectional view of a cross section of a region corresponding to the BB line of Fig. 4(b).

4(a), 4(b) and 5, the light emitting device 100c may include a light emitting structure 120 including a first conductive semiconductor layer 121, an active layer 123, and a second conductive semiconductor layer 125; a contact electrode 130; a second contact electrode 140; a first insulating portion 151 and a second insulating portion 153; a first electrode 161; a second electrode 163; a third insulating portion 170; a first wiring layer 181; and a second wiring layer 183. Further, the light-emitting element 100c may further include a first pad electrode and a second pad electrode (not shown), a growth substrate (not shown), and a wavelength conversion portion (not shown).

The third opening portion 153a of the second insulating portion 153 covers the first contact electrode 130, but the first contact electrode 130 may be partially exposed. At this time, the third opening portion 153a may be formed only to a region where a part of the holes 120h of all the holes 120h are positioned. Therefore, only a part of the ohmic contact region 131 is exposed at the third opening portion 153a, and the remaining ohmic contact region 131 may be covered by the second insulating portion 153.

The third opening portion 153a can be positioned opposite to the position of the fourth opening portion 153b. Specifically, when the fourth opening portion 153b is positioned adjacent to one side surface of the light emitting element 100c, the third opening portion 153a can Positioned adjacent to the other side, the other side being positioned opposite the one side.

On the other hand, the light-emitting element 100c of the present embodiment may further include a first wiring layer 181 and a second wiring layer 183 located under each of the first electrode 161 and the second electrode 163.

The first wiring layer 181 may electrically connect the first contact electrode 130 with the first electrode 161, and the second wiring layer 183 may electrically connect the second contact electrode 140 with the second electrode 163.

Further, when the first electrode 161 and the second electrode 163 are formed by vapor deposition or plating, the first wiring layer 181 and the second wiring layer 183 can function as a seed layer. In addition, when the first electrode 161 and the second electrode 163 are formed by sintering, the action of the wetting layer can be exerted to contribute to the stable formation of the first electrode 161 and the second electrode 163. Therefore, the first electrode 161 and the second electrode 163 can be stably followed by the first wiring layer 181 and the second wiring layer 183 to the light emitting structure 120.

Therefore, the first wiring layer 181 and the second wiring layer 183 may contain a metal substance so as to function as a seed layer or a wetting layer. For example, the first wiring layer 181 and the second wiring layer 183 may include Cu, Au, Ag, Ni, Pt, or the like.

The first wiring layer 181 and the second wiring layer 183 are not limited to the application of the present embodiment, and may be applied to other embodiments.

6(a), 6(b) and 7 are a plan view and a cross-sectional view for explaining a light-emitting element of another embodiment of the present invention.

The light-emitting element 100d of the embodiment of FIGS. 6(a), 6(b) and 7 is substantially similar to the light-emitting element 100a of FIGS. 1(a), 1(b) and 2, but further includes a connection layer 210. There are differences in aspects of the first pad electrode 231 and the second pad electrode 233. Hereinafter, the light-emitting element 100d of the present embodiment will be described focusing on the difference point, and the same configuration will not be described in detail.

6(a) is a plan view of the light-emitting element 100d, and FIG. 6(b) is a plan view for explaining the position of the hole 120h and the positions of the third opening 153a and the fourth opening 153b, and FIG. 7 is a view similar to FIG. a) A cross-sectional view of a cross section of a region corresponding to the CC line of Fig. 6(b).

6(a), 6(b) and 7 , the light emitting device 100d may include a light emitting structure 120 including a first conductive semiconductor layer 121, an active layer 123, and a second conductive semiconductor layer 125; a contact electrode 130; a second contact electrode 140; a first insulating portion 151 and a second insulating portion 153; a first electrode 161; a second electrode 163; a third insulating portion 170; a connection layer 210; and a first pad electrode 231 And a second pad electrode 233. Further, the light-emitting element 100d may further include a growth substrate (not shown) and a wavelength conversion portion (not shown).

The connection layer 210 may be located on the first electrode 161, the second electrode 163, and the third insulating portion 170.

The connection layer 210 may include a first connection layer 211, a second connection layer 213, and an insulating material layer 215. The first connection layer 211 and the second connection layer 213 are respectively disposed on the first electrode 161 and the second electrode 163, and are electrically connected to the first electrode 161 and the second electrode 163. The insulating material layer 215 insulates the first connection layer 211 from the second connection layer 213. The upper surfaces of the insulating material layer 215, the first connection layer 211, and the second connection layer 213 can be formed in parallel so as to form substantially the same plane.

The first connection layer 211 and the second connection layer 213 may include a conductive metal or a conductive oxide, a conductive nitride, or the like, and in particular, may include Au, Ag, Cu, Ni, Pt, or the like having a high conductivity. Metal formation. The insulating material layer 215 may include SiO ₂ , SiN _x , an insulating polymer, or the like.

The first pad electrode 231 and the second pad electrode 233 are located on the connection layer 210 and can be electrically connected to the first electrode 161 and the second electrode 163 through the connection layer 210. Specifically, the first pad electrode 231 and the second pad electrode 233 are electrically connected to the first electrode 161 and the second electrode 163 through the first connection layer 211 and the second connection layer 213, respectively.

The first pad electrode 231 and the second pad electrode 233 can more stably mount the light-emitting element 100d to an extra-added substrate or the like. For example, when the first electrode 161 and the second electrode 163 include a sintered body of Cu or Ag particles, the wettability of the first electrode 161 and the second electrode 163 to solder or the like is not good. Therefore, the light-emitting element 100d can be stably mounted by disposing the first pad electrode and the second pad electrode on the third insulating portion 170.

Further, the horizontal cross-sectional area of the first pad electrode 231 may be smaller than the horizontal cross-sectional area of the first electrode 161, and the horizontal cross-sectional area of the second pad electrode 233 may be larger than the horizontal cross-sectional area of the second electrode 163. In particular, the horizontal cross-sectional area of the first pad electrode 231 and the horizontal cross-sectional area of the second pad electrode 233 may be substantially the same.

In the case where the horizontal cross-sectional area of the first electrode 161 is much larger than the horizontal cross-sectional area of the second electrode 163, a defect may occur when the light-emitting element is mounted to a secondary substrate such as a Printed Circuit Board (PCB). . Further, in order to stably mount such a light-emitting element to the secondary substrate, it is necessary to change the conductive pattern of the portion where the light-emitting element is mounted on the secondary substrate. However, the light-emitting element 100d of the present embodiment further includes the first pad electrode 231 and the second pad electrode 233, whereby the electrode on the surface on which the secondary substrate of the light-emitting element 100d is mounted can be formed similarly to the normal light-emitting element 100d. Therefore, the light-emitting element 100d of the present invention can be applied to various applications by a usual light-emitting element mounting method without adding or changing a process, and the defective rate in the mounting process can be reduced.

The first pad electrode 231 and the second pad electrode 233 may include a conductive material such as a metal, and may include, for example, Ni, Pt, Pd, Rh, W, Ti, Al, Ag, Sn, Cu, Ag, Bi, In. , Zn, Sb, Mg, Pb, and the like.

On the other hand, the insulating material layer 215 may have a thickness of about 10 μm or less, whereby the efficiency of releasing heat released from the first electrode 161 and the second electrode 163 to the outside can be prevented from being lowered by the insulating material layer 215.

8(a), 8(b) and 9 are a plan view and a cross-sectional view for explaining a light-emitting element of another embodiment of the present invention.

The light-emitting element 100e of the embodiment of FIGS. 8(a), 8(b) and 9 is substantially similar to the light-emitting element 100d of FIGS. 6(a), 6(b) and 7, but includes a plurality of second There are differences in aspects of the electrode 163. Hereinafter, the light-emitting element 100e of the present embodiment will be described focusing on the difference point, and the same configuration will not be described in detail.

8(a) is a plan view of the light-emitting element 100e, and FIG. 8(b) is a plan view for explaining the position of the hole 120h and the positions of the third opening 153a and the fourth opening 153b, and FIG. 9 is a view showing FIG. And a cross-sectional view of a cross section of a region corresponding to the DD line of Fig. 8(b).

8(a), 8(b) and 9 , the light emitting device 100e may include a light emitting structure 120 including a first conductive semiconductor layer 121, an active layer 123, and a second conductive semiconductor layer 125; a contact electrode 130; a second contact electrode 140; a first insulating portion 151 and a second insulating portion 153; a first electrode 161; a second electrode 163; a third insulating portion 170; a connection layer 210; and a first pad electrode 231 And a second pad electrode 233. Further, the light-emitting element 100e may further include a growth substrate (not shown) and a wavelength conversion portion (not shown).

The second electrode 163 may be formed in plurality. Thereby, the number of the holes 120h can be increased as compared with the light-emitting elements 100d of FIGS. 6(a), 6(b) and 7 , and the area of the third opening 153a can be changed greatly. The horizontal cross-sectional area of one electrode 161 is increased. The second electrodes 163 may be spaced apart from each other, and a portion of the holes 120h may be disposed between the second electrodes 163.

According to the present embodiment, the horizontal cross-sectional area of the first electrode 161 is further increased, so that the heat dissipation efficiency of the light-emitting element 100e can be further increased, and the light-emitting characteristics can also be improved.

On the other hand, the first pad electrode 231 and the second pad electrode 233 may be omitted.

Although various embodiments of the novel creation have been described above, the present invention is not limited to the above embodiments and features. It is to be understood that various modifications and changes can be made without departing from the spirit and scope of the invention.

100a, 100b, 100c, 100d, 100e‧‧‧ light-emitting elements
120‧‧‧Lighted structure
120h‧‧‧ hole
120R‧‧‧Rough surface
121‧‧‧First Conductive Semiconductor Layer
123‧‧‧Active layer
125‧‧‧Second conductive semiconductor layer
130‧‧‧First contact electrode
131‧‧‧ Ohmic contact area
140‧‧‧Second contact electrode
151‧‧‧First insulation
153‧‧‧Second insulation
153a‧‧‧3rd opening
153b‧‧‧fourth opening
161, ‧ ‧ ‧ first electrode
163, 263‧‧‧ second electrode
170‧‧‧ Third insulation
181‧‧‧First wiring layer
183‧‧‧Second wiring layer
210‧‧‧Connection layer
211‧‧‧ first connection layer
213‧‧‧Second connection layer
215‧‧‧Insulation layer
231‧‧‧First pad electrode
233‧‧‧Second pad electrode
TL‧‧‧ tangent

1(a), 1(b) and 2 are a plan view and a cross-sectional view for explaining a light-emitting element of an embodiment of the present invention. Fig. 3 is a cross-sectional view showing a light-emitting element of another embodiment of the present invention. 4(a), 4(b) and 5 are a plan view and a cross-sectional view for explaining a light-emitting element of another embodiment of the present invention. 6(a), 6(b) and 7 are a plan view and a cross-sectional view for explaining a light-emitting element of another embodiment of the present invention. 8(a), 8(b) and 9 are a plan view and a cross-sectional view for explaining a light-emitting element of another embodiment of the present invention.

100a‧‧‧Lighting elements

120‧‧‧Lighted structure

120h‧‧‧ hole

120R‧‧‧Rough surface

121‧‧‧First Conductive Semiconductor Layer

123‧‧‧Active layer

125‧‧‧Second conductive semiconductor layer

130‧‧‧First contact electrode

131‧‧‧ Ohmic contact area

140‧‧‧Second contact electrode

151‧‧‧First insulation

153‧‧‧Second insulation

153a‧‧‧3rd opening

153b‧‧‧fourth opening

161‧‧‧First electrode

163‧‧‧second electrode

170‧‧‧ Third insulation

Claims (20)

A light-emitting element comprising: a light-emitting structure comprising a first conductive type semiconductor layer, a second conductive type semiconductor layer, and an activity between the first conductive type semiconductor layer and the second conductive type semiconductor layer a first contact electrode and a second contact electrode are disposed on the light emitting structure, and are in ohmic contact with the first conductive type semiconductor layer and the second conductive type semiconductor layer, respectively; and the first electrode and the second electrode On the light emitting structure, electrically connected to the first contact electrode and the second contact electrode, respectively, wherein a horizontal area of the first electrode is larger than a horizontal area of the second electrode. The light-emitting element according to claim 1, wherein the first electrode is located on a portion where the first contact electrode is in ohmic contact with the first conductive type semiconductor layer. The light-emitting element according to claim 2, wherein a portion of the first contact electrode that is in ohmic contact with the first conductive type semiconductor layer is not located below the second electrode. The illuminating element of claim 2, wherein the first contact electrode comprises a plurality of ohmic contact regions in contact with the first conductive type semiconductor layer to achieve ohmic contact, the first electrode and the first electrode The plurality of ohmic contact regions of the first contact electrode are all in contact. The light-emitting element of claim 2, wherein the first contact electrode comprises a contact with the first conductive type semiconductor layer to achieve ohmic contact a plurality of ohmic contact regions, only a portion of the plurality of ohmic contact regions are in contact with the first electrode. The light-emitting element according to claim 5, further comprising: a first wiring layer located under the first electrode; and a second wiring layer located under the second electrode; A portion of the first wiring layer is in contact with the first contact electrode, and a portion of the second wiring layer is in contact with the second contact electrode. The light-emitting element according to claim 6, further comprising a first insulating portion and a second insulating portion partially covering the first contact electrode and the second contact electrode, wherein the second insulating portion A portion is located between the first wiring layer and the first contact electrode. The light-emitting element according to claim 1, wherein a horizontal cross-sectional area of the first electrode is 0.8 times or more and less than 1 times a sum of horizontal cross-sectional areas of the first electrode and the second electrode. . The illuminating device of claim 1, further comprising a first pad electrode and a second pad electrode electrically connected to the first electrode and the second electrode, respectively, wherein the first pad The horizontal area of the electrode is smaller than the horizontal area of the first electrode, and the horizontal area of the second pad electrode is larger than the horizontal area of the second electrode. The light-emitting element according to claim 9, wherein a horizontal area of the first pad electrode is the same as a horizontal area of the second pad electrode. The light-emitting element of claim 9, further comprising a connection layer on the first electrode and the second electrode, wherein the connection layer comprises: an insulating material layer; a first connection layer electrically connecting the first electrode to the first pad electrode and penetrating the insulating material layer; and a second connection layer connecting the second electrode and the second electrode The pad electrode is electrically connected and penetrates the insulating material layer. The light-emitting element according to claim 9, wherein the second electrode is formed in plurality, and the second electrode is electrically connected to the second pad electrode. The illuminating element of claim 12, wherein the first contact electrode comprises a plurality of ohmic contact regions in contact with the first conductive semiconductor layer to achieve ohmic contact, wherein the plurality of ohmic contact regions are A portion of the portion is disposed between the second electrodes. The light-emitting element according to claim 1, wherein the first electrode and the second electrode respectively comprise metal particles and a non-metallic substance interposed between the metal particles. The light-emitting element according to claim 14, wherein the first electrode and the second electrode respectively comprise inclined sides, and the inclined side surface comprises a vertical cross section of each of the first electrode and the second electrode The side of the tangential inclination changes. The light-emitting element according to claim 1, wherein the light-emitting structure further comprises the active layer and the second conductive type semiconductor layer being partially removed to partially expose the first conductive type semiconductor layer The first contact electrode is in ohmic contact with the first conductive type semiconductor layer by partially exposing a region of the first conductive type semiconductor layer. The light-emitting element according to claim 16, wherein a region where the first conductive semiconductor layer is partially exposed is formed in a form of a plurality of holes. The light-emitting element according to claim 17, wherein the second contact electrode is located on the second conductive type semiconductor layer, and the first insulating portion covers the second contact electrode and the light-emitting structure. The first insulating portion includes a first opening portion and a second opening portion, and the first opening portion and the second opening portion respectively partially expose a portion of the first conductive type semiconductor layer and the first portion a portion of the two contact electrodes are exposed, the first contact electrode at least partially covering the first insulating portion, and the first contact electrode is in contact with the first conductive semiconductor layer through the first opening portion, The second insulating portion partially covers the first contact electrode, and the second insulating portion includes a third opening portion and a fourth opening portion, the third opening portion partially exposing the first contact electrode The four openings are arranged corresponding to the positions of the second openings, and a part of the second contact electrodes are exposed. The light-emitting element according to claim 18, wherein the first electrode is in contact with the first contact electrode through the third opening portion, and the second electrode is passed through the fourth opening portion The second contact electrode is in contact, and the plurality of holes are located below a region of the third opening. The light-emitting element according to claim 1, further comprising a third insulating portion covering a side surface of the first electrode and the second electrode.