WO2016003205A1 - Light emitting element - Google Patents

Abstract

Disclosed is a light emitting element. The light emitting element comprises: a first conductive type semiconductor layer; a mesa that includes an active layer and a second conductive type semiconductor layer; a current blocking layer; a transparent electrode at least partially covering the current blocking layer; a first electrode that includes a first electrode pad and a first electrode extension; a second electrode that includes a second electrode pad and a second electrode extension; and an insulation layer partially located on the lower portion of the first electrode, wherein the mesa includes at least one groove formed on a side thereof, the first conductive type semiconductor layer is partially exposed through the groove, the insulation layer includes an opening through which the exposed first conductive type semiconductor layer is at least partially exposed, the first electrode extension includes one or more extension contact portions that are brought into contact with the first conductive type semiconductor layer through an opening, and the second electrode extension includes an end that has a width different from the average width of the second electrode extension.

Description

Light emitting element

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting device, and more particularly, to a light emitting device having a structure having high current dispersion efficiency, excellent light emission efficiency, and excellent reliability.

In general, a light emitting device such as a light emitting diode includes an n-type semiconductor layer that supplies electrons, a p-type semiconductor layer that supplies holes, and an active layer positioned between the n-type semiconductor layer and the p-type semiconductor layer. An n-type electrode and a p-type electrode are formed on the n-type semiconductor layer and the p-type semiconductor layer, respectively, and power is supplied from the outside through these electrodes.

On the other hand, the p-type semiconductor layer of the nitride semiconductor series has a relatively low electrical conductivity compared to the n-type semiconductor layer. As a result, current is not effectively distributed in the p-type semiconductor layer, so that a phenomenon occurs in which current is concentrated in a specific portion of the semiconductor layer. When current is concentrated in the semiconductor layer, the light emitting diode may be vulnerable to electrostatic discharge, and leakage current and efficiency droop may occur. Accordingly, a technique of forming a transparent electrode such as ITO on the p-type semiconductor layer and disposing the p-type electrode on the ITO in order to efficiently disperse current is disclosed.

An object of the present invention is to provide a light emitting device having a structure in which current can be evenly distributed in the horizontal direction.

Another object of the present invention is to provide a light emitting device in which the second electrode, the transparent electrode, and the current blocking layer are organically combined to improve structural reliability and electrical reliability.

Another object of the present invention is to provide a light emitting device having an improved bondability of wire bonding.

A light emitting device according to an aspect of the present invention, the first conductivity type semiconductor layer; A mesa positioned on the first conductive semiconductor layer and including an active layer and a second conductive semiconductor layer positioned on the active layer; A current blocking layer partially positioned on the mesa; A transparent electrode disposed on the mesa and at least partially covering the current blocking layer; A first electrode insulated from the second conductivity type semiconductor layer and including a first electrode pad and a first electrode extension extending from the first electrode pad; A second electrode disposed on the current blocking layer and electrically connected to the transparent electrode, the second electrode including a second electrode pad and a second electrode extension extending from the second electrode pad; And an insulating layer partially positioned below the first electrode, wherein the mesa includes at least one groove formed on a side thereof, wherein the first conductive semiconductor layer is partially exposed through the groove, The insulating layer includes an opening that at least partially exposes the exposed first conductive semiconductor layer, and the first electrode extension includes one or more extension contact portions contacting the first conductive semiconductor layer through the opening. The second electrode extension includes an end having a width different from an average width of the second electrode extension.

The width of the end of the second electrode extension may be greater than the average width of the second electrode extension.

An end portion of the second electrode extension portion may be formed in a circular shape having a diameter larger than the width of the second electrode extension portion.

The second electrode extension may include an additional extension bent from an extending direction of the second electrode extension, and the additional extension may be bent in a direction away from the first electrode extension.

The additional extension may have a curved shape to have a predetermined curvature.

The additional extension may be bent in a direction toward one corner of the light emitting device.

The first electrode pad and the second electrode pad may be disposed on a vertical line passing through the center of the light emitting structure, wherein the first electrode pad is positioned adjacent to the first side of the light emitting device, and the second electrode pad May be positioned adjacent to a third side surface opposite to the first side surface of the light emitting device.

The first electrode extension portion may extend in a direction toward the first side surface along a second side surface positioned between the first side surface and the third side surface, and the second electrode extension portion may be formed in a direction greater than that of the second side surface. It may be located closer to the fourth side located opposite to the second side, and may extend in a direction toward the third side.

The shortest distance from the second electrode pad to the fourth side may be equal to the shortest distance of the fourth side branch from the end of the second electrode extension.

A plurality of openings of the insulating layer may be formed along the second side surface, and the separation distance between the openings may be constant.

The shortest distance from the first electrode extension to the second electrode extension may be greater than the distance from the end of the second electrode extension to the first electrode pad.

The gap between the openings of the insulating layer may be at least three times greater than the width of the opening of the insulating layer exposing the groove.

The current blocking layer may include a pad current blocking layer positioned below the second electrode pad and an extension current blocking layer positioned below the second electrode extension.

The transparent electrode may include a first opening positioned on the pad current blocking layer, and the second electrode pad is positioned on the pad current blocking layer to fill the first opening, and the pad current blocking layer. And partially cover a transparent electrode positioned on the upper surface of the second electrode pad, wherein the upper surface of the second electrode pad has a surface profile corresponding to an upper surface of the pad current blocking layer and a top profile of the transparent electrode positioned on the current blocking layer. Can be.

The pad current blocking layer may include a second opening that exposes the second conductive semiconductor layer, and the second electrode may contact the second conductive semiconductor layer through the second opening. The opening may be located in an area of the first opening, and an upper surface of the second electrode may be a first recessed portion located at a portion corresponding to the position of the first opening, and a portion corresponding to the position of the second opening. It may include a second recess located in the.

The current blocking layer may include a first region surrounded by the second opening, and a second region surrounding the second opening, and an upper surface of the second electrode is positioned on the first region of the current blocking layer. And a protrusion protruding from a lower surface of the second recessed portion.

The insulating layer may be located on the mesa, and the mesa may include at least one groove formed on a side thereof, and the first conductive semiconductor layer may be partially exposed through the groove. The opening may at least partially expose the first conductivity type semiconductor layer exposed to the groove.

The first electrode pad and the first electrode extension may be positioned on the mesa, and the extension contact portion may be in ohmic contact with the first conductive semiconductor layer exposed through the groove.

The insulating layer may be located on the first conductivity type semiconductor layer, the extension contact portion may include a first extension contact portion and a second extension contact portion, and the first extension contact portion May be located along one side of the mesa, and the second extension contact portion may be positioned adjacent to one edge of the mesa, and the second extension contact portion may be positioned adjacent to the first electrode pad. have.

The substrate may include a plurality of modified regions formed on at least one side surface and having a band shape extending in a horizontal direction, and a gap between a lowermost modified region of the modified regions and a lower surface of the substrate may be modified. It may be less than the gap between the topmost modified region of the substrate and the modified region of the top of the regions.

In the light emitting device according to the present invention, the position of the first electrode pad is formed in the central region in the longitudinal direction of the light emitting structure, thereby improving efficiency of the electrode forming process and the package process.

In addition, the light emitting device according to the present invention may minimize side light loss by improving contact between the first electrode extension part and the first conductivity type semiconductor layer and improve current dispersion efficiency.

In addition, the light emitting device according to the present invention has the second electrode extension portion having an additional extension portion in a curved shape, which allows the length of the second electrode extension portion to be as long as possible, while maintaining the distance from the first electrode pad. Concentration of current at the tip can be prevented.

Further, by forming a second electrode pad on the transparent electrode having an opening and interposing a part of the transparent electrode between the current blocking layer and the second electrode pad, a light emitting device having improved structural reliability and electrical reliability of the second electrode is provided. Can be.

In addition, when wire bonding to the second electrode of the light emitting device, the adhesion of the wire bonding is improved, it is possible to provide a light emitting device package with excellent reliability.

1A and 1B are plan views illustrating a light emitting device according to an embodiment of the present invention.

2 (a) to 2 (c) are cross-sectional views illustrating a light emitting device according to an embodiment of the present invention.

3 to 6 are enlarged plan views and enlarged cross-sectional views illustrating the structures of the second electrode, the current blocking layer, and the transparent electrode according to embodiments of the present invention.

7 and 8 are enlarged cross-sectional views illustrating a first electrode, a transparent electrode, and an insulating layer according to embodiments of the present invention.

9A and 9B are plan views illustrating a first electrode extension part and a second electrode extension part according to embodiments of the present invention.

10 is a cross-sectional view illustrating a light emitting device according to other embodiments of the present invention.

11 is a plan view illustrating a light emitting device according to other embodiments of the present invention.

12 is a plan view illustrating a light emitting device according to another exemplary embodiment of the present invention.

13 is a cross-sectional view illustrating a light emitting device package according to another embodiment of the present invention.

14 is a graph for explaining the effect of the structure of the current blocking layer, the transparent electrode and the second electrode according to an experimental example.

Hereinafter, with reference to the accompanying drawings will be described embodiments of the present invention; The following embodiments are provided as examples to sufficiently convey the spirit of the present invention to those skilled in the art to which the present invention pertains. Accordingly, the present invention is not limited to the embodiments described below and may be embodied in other forms. And in the drawings, the width, length, thickness, etc. of the components may be exaggerated for convenience. In addition, when one component is described as "on" or "on" another component, each component is different from each other as well as when the component is "just above" or "on" the other component. This includes cases where there is another component between them. Like numbers refer to like elements throughout.

Hereinafter, a light emitting device according to embodiments of the present invention will be described with reference to FIGS. 1A to 9.

1A and 1B are plan views illustrating a light emitting device according to an embodiment of the present invention, and FIG. 1A is an enlarged region α, an A-A 'line, a B-B' line, a C-C 'line, and FIG. 1B shows the spacing or width A1, A2, A3, A4, D1, and D2 between the configurations. (A)-(c) of FIG. 2 show sectional drawing of the part corresponding to the A-A 'line, the B-B' line, and the C-C 'line of FIG. 1A, respectively. 3 is an enlarged plan view and an enlarged cross-sectional view for describing a second electrode of a light emitting device according to an embodiment, and FIGS. 4 to 6 are enlarged plan views for explaining a second electrode of a light emitting device according to various embodiments. And enlarged cross-sectional views. 7 is a cross-sectional view illustrating a first electrode of a light emitting device according to an embodiment, and FIG. 8 is a cross-sectional view illustrating a first electrode of a light emitting device according to another embodiment. 9A and 9B are plan views illustrating the first electrode extension part and the second electrode extension part, respectively, according to an exemplary embodiment.

1A to 9, the light emitting device includes a light emitting structure 120, a current blocking layer 130, a transparent electrode 140, a first electrode 150, and a second electrode 160. It includes. In addition, the light emitting device may further include a substrate 110 and an insulating layer 170. In addition, the light emitting device may include first to fourth side surfaces 101, 102, 103, and 104, respectively. The light emitting device may have a rectangular shape having a different aspect ratio, but the shape of the light emitting device is not limited thereto.

The substrate 110 may be an insulating or conductive substrate. In addition, the substrate 110 may be a growth substrate for growing the light emitting structure 120, and may include a sapphire substrate, a silicon carbide substrate, a silicon substrate, a gallium nitride substrate, an aluminum nitride substrate, and the like. Alternatively, the substrate 110 may be a secondary substrate for supporting the light emitting structure 120. For example, the substrate 110 may be a sapphire substrate, and in particular, may be a patterned sapphire substrate (PSS) patterned on an upper surface thereof, in which case the substrate 110 may be formed of a plurality of substrates. It may include protrusions 110p.

Furthermore, the substrate 110 may include at least one modified region 111 having a band shape extending in a horizontal direction from at least one side surface of the substrate 110. The modified region 111 may be formed in the process of separating the substrate 110 and individualizing the device. For example, the modified region 111 may be formed by internally processing the substrate 110 using a stealth laser. In this case, the distance from the reformed region 111 located at the bottom of the reformed regions 111 to the bottom surface of the substrate 110 may range from the modified region 111 located at the top of the reformed regions 111 to the substrate 110. It may be less than the distance to the upper surface of the). When considering the light emitted from the side of the light emitting device, the laser beam is processed by being biased downward of the substrate 110 so that the modified region 111 is formed to be relatively biased downward, thereby to the outside of the light formed in the light emitting structure 120. Can further improve the extraction efficiency.

In this embodiment, the first conductive semiconductor layer 121 is described as being located on the substrate 110, but the substrate 110 is a growth substrate capable of growing the semiconductor layers 121, 123, and 125. In this case, after the semiconductor layers 121, 123, and 125 are grown, the semiconductor layers 121, 123, and 125 may be separated or removed through physical and / or chemical methods, and thus may be omitted.

The light emitting structure 120 may include a first conductivity type semiconductor layer 121, a second conductivity type semiconductor layer 125 and a first conductivity type semiconductor layer 121 positioned on the first conductivity type semiconductor layer 121. The active layer 123 may be disposed between the second conductive semiconductor layers 125. In addition, the light emitting structure 120 may be positioned on the first conductivity type semiconductor layer 121 and may include a mesa 120m including an active layer 123 and a second conductivity type semiconductor layer 125.

The first conductive semiconductor layer 121, the active layer 123, and the second conductive semiconductor layer 125 may be grown and formed in a chamber using a known method such as MOCVD. In addition, the first conductivity-type semiconductor layer 121, the active layer 123, and the second conductivity-type semiconductor layer 125 may include a III-V series nitride-based semiconductor, and include, for example, (Al, Ga, In And a nitride based semiconductor such as N). The first conductive semiconductor layer 121 may include n-type impurities (eg, Si, Ge. Sn), and the second conductive semiconductor layer 125 may include p-type impurities (eg, Mg, Sr, Ba). It may also be the reverse. The active layer 123 may include a multi-quantum well structure (MQW), and the composition ratio of the nitride semiconductor may be adjusted to emit a desired wavelength. In particular, in the present embodiment, the second conductivity-type semiconductor layer 125 may be a p-type semiconductor layer.

The mesa 120m is positioned on a portion of the first conductivity type semiconductor layer 121, so that the surface of the first conductivity type semiconductor layer 121 may be exposed in an area where the mesa 120m is not formed. have. The mesa 120m may be formed by partially etching the second conductivity-type semiconductor layer 125 and the active layer 123. The shape of the mesa 120m is not limited, but for example, as shown, the mesa 120m may be generally formed along the side surface of the first conductivity-type semiconductor layer 121. The mesa 120m may have an inclined side surface, but may have a side surface perpendicular to the top surface of the first conductivity type semiconductor layer 121. In addition, in the present embodiment, the mesa 120m may include at least one groove 120g recessed from the side thereof. The groove 120g may be formed along at least one side of the light emitting device, and for example, a plurality of grooves 120g may be formed along the second side surface 102 of the light emitting device. In addition, the plurality of grooves 120g may be spaced at substantially the same interval.

In addition, the mesa 120m may further include an uneven pattern (not shown) formed at a side thereof. In addition, the side surface of the first conductive semiconductor layer 121 and the side surface of the substrate 110 may further include an uneven pattern (not shown). The uneven pattern may be formed through a patterning method such as dry etching and / or wet etching. In addition, the uneven pattern may be formed in an isolation process of separating the individual elements from the wafer in manufacturing the light emitting device. Accordingly, the light extraction efficiency of the light emitting device can be improved. However, the present invention is not limited thereto, and when the light emitting device has a structure other than the horizontal structure as illustrated (for example, a vertical structure), the upper surface of the first conductive semiconductor layer 121 is exposed. It may not be.

The current blocking layer 130 is at least partially positioned on the second conductivity type semiconductor layer 125. The current blocking layer 130 may be located on the second conductive semiconductor layer 125 to correspond to a portion where the second electrode 160 is located. The current blocking layer 130 may include a pad current blocking layer 131 and an extension current blocking layer 133. The pad current blocking layer 131 and the extension current blocking layer 133 may be positioned corresponding to the positions of the second electrode pad 161 and the second electrode extension 163, respectively. Thus, as shown, the pad current blocking layer 131 is disposed adjacent to the first side 101 of the light emitting device, and the extension current blocking layer 133 is disposed from the first side 101 to the third side ( It may be arranged to extend in the direction toward 103.

The current blocking layer 130 may prevent the current from being concentrated by directly transferring the current supplied to the second electrode 160 to the semiconductor layer. Accordingly, the current blocking layer 130 may have an insulating property, may include an insulating material, and may be formed of a single layer or multiple layers. For example, the current blocking layer 130 may include SiO _x or SiN _x , or may include a distributed Bragg reflector in which insulating material layers having different refractive indices are stacked. The current blocking layer 130 may have light transmittance, may have light reflectivity, or may have selective light reflectivity.

In addition, the current blocking layer 130 may have a larger area than the second electrode 160 formed on the current blocking layer 130. Accordingly, the second electrode 160 may be located in the region where the current blocking layer 130 is formed. Further, the current blocking layer 130 may have an inclined side, in which case the transparent electrode 140 is peeled off or electrically open at the corner portion (ie, the angled portion) of the current blocking layer 130. To reduce the risk of

The transparent electrode 140 may be positioned on the second conductive semiconductor layer 125, and may also cover a portion of the top surface of the second conductive semiconductor layer 125 and a portion of the current blocking layer 130. The transparent electrode 140 may include an opening 140a partially exposing the pad current blocking layer 131. The opening 140a may be positioned on the pad current blocking layer 131, and the transparent electrode 140 may partially cover the pad current blocking layer 131. Further, the side surface of the opening 140a may be generally formed along the side surface of the pad current blocking layer 131.

The transparent electrode 140 may include a material having light transmittance and electrical conductivity, such as a conductive oxide or a light transmissive metal layer. For example, the transparent electrode 140 may be formed of indium tin oxide (ITO), zinc oxide (ZnO), zinc indium tin oxide (ZITO), zinc indium oxide (ZIO), zinc tin oxide (ZTO), gallium indium tin (GITO). Oxide), GIO (Gallium Indium Oxide), GZO (Gallium Zinc Oxide), AZO (Aluminum doped Zinc Oxide), FTO (Fluorine Tin Oxide), and may include at least one of the Ni / Au stacked structure. In addition, the transparent electrode 140 may form an ohmic contact with the second conductivity-type semiconductor layer 125. In the present exemplary embodiment, since the second electrode 160 does not directly contact the second conductive semiconductor layer 125, the current may be more effectively dispersed through the transparent electrode 140. With respect to the transparent electrode 140, it will be described in more detail later with reference to FIG.

In addition, the transparent electrode 140 may include a recess formed around the groove 120g of the mesa 120m. As shown in the enlarged view of FIG. 1A, a recess of the transparent electrode 140 may be formed along the groove 120g line of the mesa 120m. Since the transparent electrode 140 includes a concave portion, the edge line of the transparent electrode 140 may be formed to substantially follow the edge line of the mesa 120m. By forming the concave portion, the transparent electrode 140 may be formed on the side surface of the groove 120g during the manufacturing process of the light emitting device, thereby preventing the electrical short.

The second electrode 160 is positioned on the second conductive semiconductor layer 125, and at least a part of the second electrode 160 is positioned on the region where the current blocking layer 130 is located. The second electrode 160 includes a second electrode pad 161 and a second electrode extension 163, and each of the second electrode pad 161 and the second electrode extension 163 has a pad current blocking layer ( 131 and the extension current blocking layer 133. Therefore, a portion of the transparent electrode 140 may be interposed between the second electrode 160 and the current blocking layer 130. The second electrode pad 161 may be located on the opening 140a of the transparent electrode 140. The second electrode pad 161 may be in contact with the transparent electrode 140, and the side surface of the opening 140a of the transparent electrode 140 may be at least partially in contact with the second electrode pad 161. Although the position of the second electrode pad 161 is not limited, the second electrode pad 161 may be disposed to emit light in front of the active layer 123 of the light emitting device by smoothly distributing current. For example, as shown, the second electrode pad 153 may be positioned adjacent to the first side 101 opposite to the third side 103 where the first electrode pad 151 is adjacent.

The second electrode extension 163 extends from the second electrode pad 161. In the present exemplary embodiment, the second electrode extension 163 may extend from the second electrode pad 161 toward the third side surface 103. In addition, the direction in which the second electrode extension 163 extends may change as the second electrode extension 163 extends. For example, an end of the second electrode extension 163 may be bent to face a portion between the third side surface 103 and the fourth side surface 104 of the light emitting device. This may be variously designed in consideration of the distance between the first electrode pad 151 and the second electrode extension 163. The transparent electrode 140 is interposed between at least a portion of the second electrode extension 163 and the extension current blocking layer 133, so that the second electrode extension 163 is connected to the transparent electrode 140. Contact and electrically connected.

In addition, the second electrode extension 163 may include an additional extension 163 that is bent in a direction different from the direction in which the second electrode extension 163 extends. In this case, the additional extension 163 may be bent in a direction away from the first electrode extension 153. In addition, the additional electrode extension 163 may be bent toward one corner of the light emitting device, and may be bent toward an edge between the third side 103 and the fourth side 104, for example. The additional extension 163a of the second electrode extension 163 may have a curved shape along a predetermined radius of curvature, as shown in FIG. 1A. As the length of the second electrode extension 163 is longer, the current dispersion efficiency may be improved. In this case, the distance from the end 163e of the second electrode extension 163 to the first electrode pad 151 is too long. If it becomes short, a phenomenon may occur in which current is concentrated at the end 163e of the second electrode extension 163. According to this embodiment, the second electrode extension 163 and the second electrode extension 163 and the first electrode by including an additional extension 163 having a form curved along a predetermined radius of curvature, The distance from the pad 151 can be maintained at a predetermined distance or more. Accordingly, it is possible to prevent the current from concentrating on the end 163e of the second electrode extension 163.

In addition, the end 163e of the second electrode extension 163 may include a portion having a width greater than the average width of the second electrode extension 163. For example, as shown in FIG. 9B, the end 163e of the second electrode extension 163 may be formed in a circular shape having a diameter larger than the width of the second electrode extension 163. In this case, the diameter of the end 163e may be about 0.5 to 5 μm larger than the width of the second electrode extension 163. However, the present invention is not limited thereto, and the shape of the end 163e of the second electrode extension 163 may be modified in various shapes such as polygonal, elliptical, and arc.

By forming the end 163e of the second electrode extension 163 to have a relatively large width, it is possible to improve current dispersion in a region around the end 163e of the second electrode extension 163. In addition, the area of the end 163e portion of the second electrode extension portion 163 is widened, so that the second electrode extension portion 163 is the transparent electrode 140 at the end portion 163e portion of the second electrode extension portion 163. It is possible to effectively prevent the defect of the light emitting device from being peeled off from, and to increase the contact resistance at the end 163e of the second electrode extension 163. In addition, the second electrode 160 is mainly formed through a photolithography process. At this time, a problem may occur that the development is not performed properly around the end 163e of the second electrode 160. When the area of the end portion 163e of the second electrode extension portion 163 is made relatively large, the photolithography process margin may be further provided to prevent defects that may occur during the formation of the second electrode 160. Can be. Thereby, the reliability of a light emitting element can be improved.

On the other hand, the arrangement of the second electrode 160 is not limited thereto, and may be variously modified and changed according to the shape of the light emitting device.

The second electrode 160 may include a metal material, may include Ti, Pt, Au, Cr, Ni, Al, or the like, and may be formed in a single layer or a multilayer structure. For example, the second electrode 160 includes a Ti layer / Au layer, a Ti layer / Pt layer / Au layer, a Cr layer / Au layer, a Cr layer / Pt layer / Au layer, a Ni layer / Au layer, and a Ni layer / It may include at least one of a metal stacked structure of Pt layer / Au layer, and Cr layer / Al layer / Cr layer / Ni layer / Au layer.

Hereinafter, the mutual coupling relationship between the pad current blocking layer 131, the transparent electrode 140, and the second electrode pad 161 will be described in more detail with reference to FIG. 3.

As illustrated in FIGS. 3A and 3B, the pad current blocking layer 131 may have a generally circular planar shape. However, the pad current blocking layer 131 may be formed in various shapes such as a polygonal shape, and may be formed to substantially correspond to the planar shape of the second electrode pad 161. The transparent electrode 140 may cover a portion of the side surface and the upper surface of the pad current blocking layer 131, and in particular, may cover a peripheral edge of the pad current blocking layer 131. Since the transparent electrode 140 partially covers the pad current blocking layer 131, the surface profile formed between the top surface of the transparent electrode 140 and the top surface of the pad current blocking layer 131 is not flat and is curved. It can be lost or have a step.

At least a portion of the opening 140a of the transparent electrode 140 may be positioned on the pad current blocking layer 131, and in the present embodiment, the shape of the opening 140a is an outer edge shape of the current blocking layer 130. It can correspond to. For example, as shown in FIG. 3, when the pad current blocking layer 131 is formed in a circular shape, the transparent electrode 140 may cover the periphery of the circular edge to form the opening 140a in a circular shape. . Since the opening 140a is formed to have a shape corresponding to the outer edge shape of the pad current blocking layer 131, the transparent electrode 140 may be prevented from being peeled from the current blocking layer 130. However, the shape of the opening 140a is not limited to the above, and may have various shapes. In addition, a plurality of openings 140a may be formed.

The contact resistance between the second electrode pad 161 and the second conductive semiconductor layer 125 is higher than the contact resistance between the transparent electrode 140 and the second conductive semiconductor layer 125. Therefore, when a current is supplied through the second electrode pad 161, the current is likely to flow to the transparent electrode 140 having low resistance, so that the current can be effectively distributed in the horizontal direction by the transparent electrode 140. Furthermore, in the present embodiment, since the second electrode pad 161 does not directly contact the second conductive semiconductor layer 125, current can be more effectively dispersed.

The second electrode 160 may be in contact with the current blocking layer 130 by filling the first opening 140a and may partially cover the transparent electrode 140 positioned on the current blocking layer 130. Accordingly, the second electrode 160, in particular, the second electrode pad 161 is in contact with the transparent electrode 140. In this case, the horizontal area of the second electrode pad 161 may be larger than that of the opening 140a of the transparent electrode 140, and thus the opening 140a may be covered by the second electrode pad 161. have. As shown in FIG. 3, the second electrode pad 161 may be formed in a circular shape having a radius of R1, and the opening 140a of the transparent electrode 140 may be formed in a circular shape having a radius of R2. Can be. At this time, R1 is larger than R2. The size of R1 and R2 may be controlled to provide sufficient wire bonding area and to prevent peeling of the second electrode pad 161 and the transparent electrode 140. R1 may have a value of about 5-15 μm greater than R2. For example, the second electrode pad 161 may have a radius R1 of about 35 μm, and the opening 140a of the transparent electrode 140 may have a radius R2 of about 25 μm.

An upper surface of the second electrode pad 161 may not be flat. In detail, the upper surface of the second electrode pad 161 may have a surface profile corresponding to a surface profile of the upper surface of the transparent electrode 140 and the upper surface of the pad current blocking layer 131. That is, since the second electrode pad 161 is positioned on the transparent electrode 140 and the pad current blocking layer 131 whose surface profile is not flat, the surface of the second electrode pad 161 may be curved or have a step. As illustrated in FIG. 3, the upper surface of the second electrode pad 161 may have at least one recessed portion 161g positioned on a region where the opening 140a is located. Accordingly, the upper surface of the second electrode pad 161 may have a surface having a step. In particular, the depression 161g may be formed in a circular shape as shown in FIG. Therefore, when the second electrode pad 161 is formed in a circular shape, the outer edge of the second electrode pad 161 and the edge of the recess 161g may be formed in a concentric shape.

Since the second electrode pad 161 has a non-flat surface profile, when wire bonding the upper surface of the second electrode pad 161, adhesion between the wire and the second electrode pad 161 may be improved. Therefore, disconnection of the wire at the portion where the wire is bonded to the second electrode pad 161 can be effectively prevented. In addition, the second electrode pad 161 is positioned on the transparent electrode 140 and the pad current blocking layer 131 having a flat surface profile, such that the second electrode pad 161 is connected to the current blocking layer 130 and / or. Alternatively, peeling from the transparent electrode 140 may be prevented. That is, when the second electrode pad 161 is formed on a stepped or curved surface than when the second electrode pad 161 is formed on a flat surface, the second electrode pad 161 may be more stably disposed, and thus, the second electrode. Peeling of the pad 161 is prevented. In addition, since a portion of the transparent electrode 140 is positioned between the pad current blocking layer 131 and the second electrode pad 161, the transparent electrode 140 may be more stably disposed and thus the transparent electrode 140. ) Is prevented from peeling off. Therefore, structural stability between the second electrode 160, the current blocking layer 130, and the transparent electrode 140 can be improved.

4 to 6 are plan views and cross-sectional views for describing the structures of the current blocking layer, the transparent electrode, and the second electrode according to various embodiments of the present invention. Hereinafter, various structures will be described in detail with reference to the accompanying drawings. . In the following embodiments, the reference numerals of the components are displayed with different hundreds digits. For example, in FIG. 3, the current blocking layer is labeled 130, and in FIG. 4, the current blocking layer is labeled 230. This is a different reference numerals for the convenience of structural description, the material properties of each component, and the like.

First, referring to FIG. 4, the transparent electrode 240 includes a first opening 240a, and the pad current blocking layer 231 of the present embodiment has a second opening exposing the second conductive semiconductor layer 125. 231a may be included. Accordingly, the second electrode pad 261 is in contact with the second conductivity type semiconductor layer 125 through the second opening 231a.

The second opening 231a may be located in an area where the first opening 240a is positioned, and the transparent electrode 240 may cover an outer edge portion of the pad current blocking layer 231. Thus, a stepped surface profile is formed, which is formed of an upper surface of the transparent electrode 240, an upper surface of the pad current blocking layer 231, and an upper surface of the second conductive semiconductor layer 125 under the second opening 231a. Accordingly, the upper surface of the second electrode pad 261 may have a first recess 261ga corresponding to the position of the first opening 240a and a second recess 261gb corresponding to the position of the second opening 231a. It may include.

In this case, the horizontal area of the second electrode pad 261 may be larger than that of the first opening 240a of the transparent electrode 240, and the horizontal area of the first opening 240a is the horizontal area of the second opening 231a. Can be greater than Accordingly, the openings 240a and 231a may be covered by the second electrode pad 261. As shown in FIG. 4, the second electrode pad 261 may be formed in a circular shape having a radius of R1, and the first opening 240a of the transparent electrode 240 may have a circular shape having a radius of R2. It may be formed, the second opening 231a may be formed in a circular shape having a radius of R3. At this time, R1 is larger than R2 and R2 is larger than R3. The size of R1 to R3 may be controlled to provide sufficient wire bonding area and to prevent peeling of the second electrode pad 261 and the transparent electrode 240.

As the pad current blocking layer 231 includes the second openings 231a, more steps and curvatures are formed on the upper surface of the second electrode pad 261. Accordingly, the second electrode pad 261 may be more stably disposed, and the wire may be more stably bonded during wire bonding.

Next, referring to FIG. 5, the transparent electrode 340 of the present exemplary embodiment includes a first opening 340a, and the pad current blocking layer 331 exposes the second conductive semiconductor layer 125. 331a may be included. In addition, the transparent electrode 340 may cover the pad current blocking layer 331. In particular, as illustrated, the transparent electrode 340 may cover the side surface of the second opening 331a of the pad current blocking layer 331. Accordingly, the second electrode pad 361 is in contact with the second conductivity type semiconductor layer 125 through the second opening 331a and the first opening 340a.

An upper surface of the second electrode pad 361 may include a depression 361g corresponding to the position of the first opening 340a. According to the present exemplary embodiment, the pad current blocking layer 331 includes a second opening 331a, but the transparent electrode 340 covers the pad current blocking layer 331. Accordingly, the upper surface of the second electrode pad 361 may include a recess 361g having a depth greater than the thickness of the pad current blocking layer 331. Also, a second electrode pad 361 having a deeper depression 361g may be provided than in the case of FIG. 3.

Furthermore, as shown in FIG. 4, the second electrode pad 361 may be formed in a circular shape having a radius of R1, and the first opening 340a of the transparent electrode 340 has a circular shape having a radius of R2. It may be formed in the shape, the second opening 331a may be formed in a circular shape having a radius of R3. At this time, R1 is larger than R2 and R2 is larger than R3. The size of R1 to R3 may be controlled to provide sufficient wire bonding area and to prevent peeling of the second electrode pad 361 and the transparent electrode 340.

Referring to FIG. 6, the pad current blocking layer 431 may include a second opening portion 431a exposing the second conductivity type semiconductor layer 125, a first portion 4311 and a second portion surrounded by the second opening portion 431a. It may include a second portion 4312 surrounding the opening 431a. The transparent electrode 340 may partially cover the outer edge region of the second portion 4312 of the pad current blocking layer 331. At this time, the upper surface of the second portion 4312 is partially exposed. Therefore, the upper surface of the transparent electrode 440, the upper surface of the second portion 4312 of the pad current blocking layer 431, the upper surface of the second conductive semiconductor layer 125 under the second opening 431a, and the first portion Surface profiles are formed in which the top surfaces of 4311 have steps with each other. Accordingly, the upper surface of the second electrode pad 461 may have a first recessed portion 461ga corresponding to the position of the first opening 440a and a second recessed portion 461gb corresponding to the position of the second opening 431a. , And a protrusion 461p corresponding to the position of the first portion 4311.

Since the pad current blocking layer 431 includes the second opening 431a and the first portion 4311 surrounded by the second opening 431a, the stepped current and the stepped portion are more relatively higher than the top surface of the second electrode pad 461. Is formed. Accordingly, the second electrode pad 461 may be more stably disposed, and the wire may be more stably bonded at the time of wire bonding.

Meanwhile, in the embodiments of FIGS. 4 to 6, the second electrodes 260, 360, and 460 may be in contact with the second conductivity type semiconductor layer 125. In this case, the second electrodes 260, 360, and 460 and the second conductive semiconductor layer 125 may not form ohmic contacts well, and the second electrodes 260, 360, and 460 may have high contact resistance at the interface. The lower surface of can be formed. For example, the second electrodes 260, 360, and 460 may be formed in a multi-layered structure, and the bottommost layer may be formed of a material in which ohmic contacts are not easily formed with the second conductive semiconductor layer 125. . Therefore, when the current is supplied, the current flows to the transparent electrodes 240, 340, and 440 having relatively low contact resistance at the interface, so that the current dispersion efficiency does not decrease.

The structure of the second electrode, the transparent electrode, and the current blocking layer in various embodiments of the present invention have been described above, but the present invention is not limited thereto.

Referring back to FIGS. 1A through 3, the first electrode 150 is electrically connected to the first conductive semiconductor layer 121. The first electrode 150 contacts the top surface of the first conductive semiconductor layer 121 where the second conductive semiconductor layer 125 and the active layer 123 are partially removed to expose the first electrode semiconductor layer 125. It may be electrically connected to the 121. The first electrode 150 may include a first electrode pad 151 and a first electrode extension 153. The first electrode extension 153 includes at least one extension contact portion 153a. The extension contact portion 153a may be in ohmic contact with the first conductivity type semiconductor layer 121. In the present embodiment, a part of the first electrode pad 151 and the first electrode extension 153 may be located on the mesa 120m, and at this time, the mesa 120m and the first electrode 150 An insulating layer 170 may be interposed between the portions.

The first electrode 150 may serve to supply external power to the first conductive semiconductor layer 121, and the first electrode 150 may be formed of a metal such as Ti, Pt, Au, Cr, Ni, Al, or the like. It may include a substance. In addition, the first electrode 150 may be formed of a single layer or multiple layers.

The first electrode pad 151 may be disposed adjacent to the third side surface 103 of the light emitting device, and the first electrode extension 153 may be formed along the third side surface 103 and the second side surface 102. It may extend toward one side 101. In general, in the case of a rectangular light emitting device having a different aspect ratio, a first electrode pad is formed in a corner region of the light emitting device. However, when the first electrode pad is formed in the corner region, a part of the lead frame may be damaged during the ball bonding or the wire bonding process. Therefore, as in this embodiment, by forming the first electrode pad 151 in the central region in the longitudinal direction of the light emitting structure 120, it is possible to improve the efficiency of the bonding process, packaging process and the like.

In this case, the first electrode pad 151 may be formed to be spaced at least 50 μm or more from an outer side surface of the light emitting structure 120 in order to improve process efficiency by securing an appropriate level of process margin during packaging. However, when the first electrode pad 151 is spaced too far from the outer side surface of the light emitting structure 120, the luminous efficiency of the outer area of the light emitting structure 120 may be reduced. Therefore, the first electrode pad 151 may be located about 50 μm to 200 μm from the outer side surface of the light emitting structure 120. However, the present invention is not limited thereto.

The insulating layer 170 may be positioned between the light emitting structure 120 and the first electrode 150, and may also expose the first conductivity-type semiconductor layer 121 exposed by the groove 120g of the mesa 120m. It may include an opening 170a to partially expose the.

As shown in FIG. 1A, a portion of the insulating layer 170 is positioned under the first electrode pad 151 to electrically insulate the first electrode pad 151 from the second conductive semiconductor layer 125. . In addition, an area of the insulating layer 170 positioned below the first electrode pad 151 may be larger than an area of the first electrode pad 151, and an insulating layer positioned below the first electrode pad 151. 170 may cover side surfaces of the light emitting structure 120. Accordingly, the first electrode pad 151 and the second conductivity-type semiconductor layer 125 may be effectively prevented from being electrically shorted, and may be caused by electrical bonding to the first electrode pad 151. Short circuits can also be prevented.

In addition, in one embodiment, as shown in FIG. 7, the insulating layer 170 positioned below the first electrode pad 151 may be spaced apart from the transparent electrode 140. In this case, leakage current due to a defect present in the insulating layer 170 may be prevented from flowing to the transparent electrode 140. In other embodiments, as shown in FIG. 8, the insulating layer 170 positioned below the first electrode pad 151 may be in contact with the transparent electrode 140, and further, the transparent electrode 140. It may partially cover the side and top of the. In this case, when wire bonding on the first electrode pad 151, a bonding material flows through the side surface of the first electrode pad 151 and prevents an electrical short circuit that may occur due to contact with the transparent electrode 140.

The opening 170a of the insulating layer 170 may at least partially expose the groove 120g. The extension contact portion 153a is positioned on the first conductive semiconductor layer 121 exposed by the opening 170a and the groove 120g of the mesa 120m, and in this portion, the first conductive semiconductor layer ( 121) may be electrically connected. In addition, the insulating layer 170 partially covers the side surface of the groove 120g to prevent the first electrode extension 153 from coming into contact with the side surface of the light emitting structure 120 to prevent an electrical short circuit.

As such, the portion of the first electrode pad 151 does not directly contact the first conductive semiconductor layer 121, and the extension contact portion 153a of the first electrode extension 153 is the first conductive semiconductor. By contacting the layer 121 to form an electrical connection, the current can be smoothly dispersed in the horizontal direction when driving the light emitting device. When the first electrode 150 is an n-type electrode, electrons are injected from the first electrode 150. In this case, when the entire first electrode extension 153 contacts the first conductive semiconductor layer 121, electrons are injected into the first conductive semiconductor layer 121 according to a distance from the first electrode pad 151. The density of can vary. Therefore, in this case, current spreading performance may be lowered. In contrast, according to the present exemplary embodiment, the first conductive type semiconductor layer 121 is contacted through the extension contact portion 153a of the first electrode extension 153, but the remaining portion of the first electrode extension 153 is in contact with the first conductive extension layer 153. They are insulated from the first conductivity type semiconductor layer 121 by the insulating layer 170. Accordingly, electron injection may be made through the extension contact portion 153a to maintain the electron injection density in the plurality of extension contact portions 153a in a similar manner. Accordingly, electrons can be smoothly injected even through a portion of the first electrode extension portion 153 that is relatively far from the first electrode pad 151, thereby improving current dispersion efficiency of the light emitting device.

Meanwhile, referring to FIG. 1B, the width of the portion where the extension contact portion 153a of the first electrode extension portion 153 contacts the first conductive semiconductor layer 121, that is, the opening of the insulating layer 170 may be The width D1 of the 170a may be smaller than the gap D2 between the openings 170a of the insulating layer 170. Furthermore, D2 may further improve the dispersibility of the current injected through the extension contact portion 153a by adjusting the gap to be three times larger than D1.

In addition, the end 153e of the first electrode extension 153 may include a portion having a width greater than the average width of the first electrode extension 153. For example, as shown in FIG. 9A, the end 153e of the first electrode extension 153 may be formed in a circular shape having a diameter larger than the width of the first electrode extension 153. In this case, the diameter of the end 153e may be about 0.5 to 5 μm larger than the width of the first electrode extension 153. However, the present invention is not limited thereto, and the shape of the end 153e of the first electrode extension part 153 may be modified in various forms such as polygon, ellipse, and arc.

By forming the end 153e of the first electrode extension 153 to have a relatively large width, current dispersion in the area around the end 153e of the first electrode extension 153 can be improved. In addition, the area of the end 153e portion of the first electrode extension portion 153 may be widened to effectively prevent the defective light emitting device from being peeled off from the end portion 153e portion of the first electrode extension portion 153. have. In addition, the first electrode 150 is mainly formed through a photolithography process. At this time, a problem may occur that the development is not performed properly around the end 153e of the first electrode 150. When the area of the end 153e portion of the first electrode extension 153 is made relatively large, the photolithography process margin may be further provided to prevent defects that may occur in the process of forming the first electrode 150. Can be. Thereby, the reliability of a light emitting element can be improved.

On the other hand, the arrangement of the first electrode 150 and the second electrode 160 is not limited thereto, and may be variously modified and changed according to the shape of the light emitting device and the applied current. The arrangement of the first electrode pad 151 and the first electrode extension 153 may be changed in relation to each other according to the arrangement of the second electrode pad 161 and the first electrode extension 153.

For example, referring to FIG. 1B, the distance A1 from the first electrode extension 153 extending along the second side surface 102 of the light emitting device to the second electrode extension 163 is the second electrode extension. It is larger than the distance A2 from the end 163e of 163 to the first electrode pad 151. The second electrode extension 163 extends in the direction toward the first electrode pad 151, but the first electrode extension 153 extending along the second electrode extension 163 and the second side surface 102. By keeping the distance to substantially constant, current dispersion efficiency can be improved. In addition, by forming A2 smaller than A1, the current density is lowered around the end of the second electrode extension 163 to prevent the current dispersion efficiency from being lowered.

In addition, the distance A3 from the end 163e of the second electrode extension 163 to the outer edge of the transparent electrode 140 (the edge disposed along the fourth side surface 104) is the second electrode pad 161. ) May be substantially the same as the distance from the side surface of the transparent electrode 140 to the outer edge (the edge disposed along the fourth side surface 104). At this time, A3 may be about 50 to 60 ㎛.

In addition, the second electrode extension 163 may be located on the fourth side 104 side rather than the second side surface 102 of the light emitting device. As shown, the second electrode extension 163 is located closer to the fourth side 104 than the second side 102 of the light emitting device, and is formed from the longitudinal centerline CL passing through the center of the light emitting device. The two electrode extensions 163 may be spaced apart from the predetermined distance A4. The A4 may be about 14-18 μm. Since the first electrode extension 153 is located adjacent to the second side surface 102, the second electrode extension 163 is positioned closer to the fourth side 104 than the second side surface 102. Current dispersion can be improved.

10 is a cross-sectional view illustrating a light emitting device according to other embodiments of the present invention. The light emitting device of FIG. 10 is generally similar to the light emitting device described with reference to FIGS. 1A to 9, except that the light emitting device further includes a reflective layer 510 disposed under the light emitting structure 120. Hereinafter, the light emitting device of the present embodiment will be described based on the difference, and detailed description of the same configuration will be omitted.

Referring to FIG. 10, the light emitting device may include a light emitting structure 120, a current blocking layer 130, a transparent electrode 140, a first electrode 150, a second electrode 160, and a reflective layer ( 510). In addition, the light emitting device may further include a substrate 110 and an insulating layer 170. In addition, the light emitting device may include first to fourth side surfaces 101, 102, 103, and 104, respectively.

The reflective layer 510 may be positioned below the light emitting structure 120, and may be positioned below the substrate 110 when the light emitting device further includes the substrate 110. The reflective layer 510 may be formed of a light reflective material to reflect light emitted from the light emitting structure 120.

The reflective layer 510 may include a distributed Bragg reflector having a structure in which dielectric layers having different refractive indices are stacked. In this case, the reflective layer 510 includes a laminate structure 511 in which a first dielectric layer having a first refractive index and a second dielectric layer having a second refractive index are repeatedly stacked, and an interface layer 510 positioned on the stacked structure 511. It may include. The interfacial layer 510 may serve as an adhesive layer on which the stacked structure 511 may be formed, and also improve the interfacial properties of the first and second dielectric layers included in the stacked structure 511. have. Therefore, the thickness of the interface layer 510 may be formed thicker than the thickness of each layer of the laminate structure 511.

For example, the first dielectric layer may be formed by including TiO ₂ or TiO _2, the second dielectric layer may be formed to include a SiO ₂ or SiO _2. In addition, the interface layer 510 may be formed of or include a SiO ₂ SiO _2. In this case, of the layers of the stacked structure 511, the layer contacting the interface layer 510 may be a first dielectric layer. Therefore, when viewed as a whole of the reflective layer 510, the reflective layer 510 may be formed in a structure in which layers formed of different materials are repeatedly stacked. However, the present invention is not limited thereto.

In addition, when the reflective layer 510 is formed under the substrate 110, the RMS roughness of the lower surface of the substrate 110 may be 100 nm or less. This can be achieved through known surface planar techniques, for example, to control the RMS roughness of the bottom surface of the substrate 110 through a CMP process. As the lower surface of the substrate 110 has an RMS roughness of 100 nm or less, an unbalance occurs in the first dielectric layer or the second dielectric layer by the substrate 110 having a low adhesive strength or a large surface roughness during high temperature heat treatment, and thus the reflective layer 510 ) Can prevent cracks from occurring.

The reflective layer 510 may further include a layer formed of a light reflective metal, or may be formed of a light reflective metal instead of the stack structure 511. In this case, the layer formed of the light reflective metal may be formed of multiple layers or a single layer, and may include Al, Au, Pt, and the like.

11 is a plan view illustrating a light emitting device according to other embodiments of the present invention. The light emitting device of FIG. 11 is generally similar to the light emitting device described with reference to FIGS. 1A to 9. Hereinafter, the light emitting device of the present embodiment will be described based on the difference, and detailed description of the same configuration is omitted.

The light emitting device includes a light emitting structure 120, a current blocking layer 130, a transparent electrode 140, a first electrode 150, and a second electrode 160. Furthermore, the light emitting device may further include a substrate 110, an insulating layer 170, and a reflective layer 510. In addition, the light emitting device may include first to fourth side surfaces 101, 102, 103, and 104, respectively. The light emitting device may have a rectangular shape having a different aspect ratio, but the shape of the light emitting device is not limited thereto.

The light emitting element of this embodiment includes a mesa 120m including a groove 120g 'having an arc shape in plan view. Comparing the degree of depression from the side of the mesa (120m), the groove (120g ') is formed to be more embedded than the groove (120g) shown in Figure 1a. Accordingly, the distance from the extension contact portion 153a to the adjacent transparent electrode 140 may be larger than that of the light emitting device of FIGS. 1A to 9. Accordingly, an electrical short circuit that may occur around the extension contact portion 153a may be effectively prevented. In addition, the width of the portion where the extension contact portion 153a contacts the first conductivity-type semiconductor layer 121 may be larger than that of the light emitting device of FIGS. 1A to 9.

In addition, the distance A2 ′ from the end 163e of the second electrode extension 163 to the first electrode pad 151 may be larger than that of the light emitting device of FIGS. 1A to 9, and the second The distance A3 ′ from the end 163e of the electrode extension 163 to the outer edge of the transparent electrode 140 (the edge disposed along the fourth side surface 104) is determined by the light emitting device of FIGS. 1A to 9. It may be smaller than in the case.

That is, as in the present embodiment, by modifying the shape and size of the groove 120g 'of the mesa 120m, and the arrangement of the first and second electrodes 150 and 160, the current dispersion efficiency according to the driving current of the light emitting device and the like. Can be further improved.

12 is a plan view illustrating a light emitting device according to another exemplary embodiment of the present invention. The light emitting device of FIG. 12 is generally similar to the light emitting device described with reference to FIGS. 1A to 9. Hereinafter, the light emitting device of the present embodiment will be described based on the difference, and detailed description of the same configuration is omitted.

The light emitting device includes a light emitting structure 120, a current blocking layer 130, a transparent electrode 140, a first electrode 150, and a second electrode 160. Furthermore, the light emitting device may further include a substrate 110, an insulating layer 170, and a reflective layer 510. In addition, the light emitting device may include first to fourth side surfaces 101, 102, 103, and 104, respectively. The light emitting device may have a rectangular shape having a different aspect ratio, but the shape of the light emitting device is not limited thereto.

The first electrode 150 according to the present embodiment is positioned on the first conductive semiconductor layer 121. That is, the first electrode 150 may not be positioned on the mesa 120m and may be adjacent to the side of the mesa 120m. The insulating layer 170 may be partially interposed between the first electrode 150 and the first conductive semiconductor layer 121. In addition, the insulating layer 170 may include two or more openings 170a exposing a portion of the first conductivity-type semiconductor layer 121. In this case, the first electrode extension 153 includes a first extension contact portion 153a and a second extension contact portion 153b. The first extension contact portion 153a may contact the first conductivity type semiconductor layer 121 through openings 170a formed along the long side of the mesa 120m. The second extension contact portion 153b may be positioned adjacent to the first electrode pad 151 and may be in ohmic contact with the first conductive semiconductor layer 121 exposed on the side surface of the mesa 120m. In this case, the second extension contact portion 153b may be positioned around the edge of the mesa 120m. As described above, the second extension contact portion 153b is formed in addition to the first extension contact portion 153a to contact the first conductivity type semiconductor layer 121, thereby forming a region in the area around the first electrode pad 151. Current dispersion can be further improved.

13 is a cross-sectional view illustrating a light emitting device package according to another embodiment of the present invention.

Referring to FIG. 13, the light emitting device package 600 includes a light emitting device 100, a first lead 631 and a second lead 633 electrically connected to the light emitting device 100, and wires 611 and 613. ). Furthermore, the LED package 600 may further include a base 620 and a reflector 623.

The light emitting device 100 may be mounted on the base 620, and in particular, may be mounted on the second lead 633 or the first lead 631. In this case, the light emitting device 100 may be surrounded by the reflector 623 formed along the side of the base 620, the reflector 623 has an inclined surface, thereby reflecting light to improve the luminous efficiency of the light emitting device package. Can be.

The light emitting device 100 may be one of the light emitting devices according to the embodiments described with reference to FIGS. 1A to 12 or a light emitting device modified therefrom. As described above, the second electrode pad 161 of the light emitting device 100 has a non-flat surface profile, and in particular, includes a depression 161g corresponding to the opening 140a. The second electrode pad 161 is electrically connected to the second lead 633 through the second wire 613.

In this case, the second wire 613 may be electrically connected to the second electrode pad 161 through ball bonding. As illustrated, when ball bonding the second wire 613 and the second electrode pad 161, the second wire 613 is formed due to the depression 161g formed on the surface of the second electrode pad 161. ) May be stably adhered to the second electrode pad 161. Therefore, it is possible to prevent wire contact defects that may occur during the light emitting device package process, and to prevent wire breakage due to internal and external factors even after manufacture, thereby improving reliability of the light emitting device package.

In addition, the light emitting device has excellent current dispersing efficiency and can have excellent efficiency even in a relatively high current driving environment. Therefore, the light emitting device package including the light emitting device may be used even when high current driving is required.

In the above, various embodiments of the present invention have been described, but the present invention is not limited to the various embodiments and features described above, and various modifications may be made without departing from the technical spirit of the claims of the present invention. Modifications and variations are possible.

Claims (20)

A first conductivity type semiconductor layer; A mesa positioned on the first conductive semiconductor layer and including an active layer and a second conductive semiconductor layer positioned on the active layer; A current blocking layer partially positioned on the mesa; A transparent electrode disposed on the mesa and at least partially covering the current blocking layer; A first electrode insulated from the second conductivity type semiconductor layer and including a first electrode pad and a first electrode extension extending from the first electrode pad; A second electrode disposed on the current blocking layer and electrically connected to the transparent electrode, the second electrode including a second electrode pad and a second electrode extension extending from the second electrode pad; And An insulating layer partially positioned below the first electrode, The mesa includes at least one groove formed on a side thereof, the first conductive semiconductor layer is partially exposed through the groove, The insulating layer includes an opening that at least partially exposes the exposed first conductive semiconductor layer, wherein the first electrode extension includes one or more extension contact portions contacting the first conductive semiconductor layer through the opening. Including, And the second electrode extension portion includes an end having a width different from an average width of the second electrode extension portion. The method according to claim 1, The width of the end of the second electrode extension is larger than the average width of the second electrode extension. The method according to claim 2, An end of the second electrode extension is formed in a circular shape having a diameter larger than the width of the second electrode extension. The method according to claim 1, The second electrode extension portion includes an additional extension portion bent from an extending direction of the second electrode extension portion, the additional extension portion is bent in a direction away from the first electrode extension portion. The method according to claim 4, The additional extension is a light emitting device having a curved shape to have a predetermined curvature. The method according to claim 4, The additional extension is a light emitting device that is bent in a direction toward one corner of the light emitting device. The method according to claim 1, The first electrode pad and the second electrode pad are disposed on a vertical line passing through the center of the light emitting structure, The first electrode pad is positioned adjacent to the first side of the light emitting element, and the second electrode pad is positioned adjacent to the third side facing the first side of the light emitting element. The method according to claim 7, The first electrode extension portion extends in a direction toward the first side along a second side surface positioned between the first side surface and the third side surface, The second electrode extension part is positioned closer to the fourth side surface positioned opposite to the second side surface than the second side surface, and extends in the direction toward the third side surface. The method according to claim 8, The shortest distance from the second electrode pad to the fourth side surface is the same as the shortest distance of the fourth side branch from the end of the second electrode extension. The method according to claim 7, A plurality of openings of the insulating layer is formed along the second side surface, the separation distance between the openings are constant. The method according to claim 1, The shortest distance from the first electrode extension to the second electrode extension is greater than the distance from the end of the second electrode extension to the first electrode pad. The method according to claim 1, The gap between the openings of the insulating layer is greater than three times the width of the opening of the insulating layer for exposing the groove. The method according to claim 1, The current blocking layer includes a pad current blocking layer positioned below the second electrode pad and an extension current blocking layer positioned below the second electrode extension. The method according to claim 13, The transparent electrode includes a first opening located on the pad current blocking layer, The second electrode pad is disposed on the pad current blocking layer to fill the first opening, and partially covers the transparent electrode located on the pad current blocking layer. The upper surface of the second electrode pad has a surface profile corresponding to the upper surface of the pad current blocking layer and the upper profile of the transparent electrode positioned on the current blocking layer. The method according to claim 14, The pad current blocking layer includes a second opening that exposes the second conductive semiconductor layer, and the second electrode contacts the second conductive semiconductor layer through the second opening. The second opening is located within an area of the first opening, The upper surface of the second electrode includes a first recessed portion located in a portion corresponding to the position of the first opening, and a second recessed portion located in a portion corresponding to the position of the second opening. The method according to claim 15, The current blocking layer includes a first region surrounded by the second opening, and a second region surrounding the second opening, The upper surface of the second electrode is located on the first region of the current blocking layer, and the light emitting device including a protrusion protruding from the lower surface of the second recessed portion. The method according to claim 1, The insulating layer is located on the mesa, The mesa includes at least one groove formed on a side thereof, the first conductive semiconductor layer is partially exposed through the groove, The opening of the insulating layer is a light emitting device to at least partially expose the first conductive semiconductor layer exposed to the groove. The method according to claim 17, The first electrode pad and the first electrode extension part are positioned on the mesa, wherein the extension part contact portion ohmic contact with the first conductivity type semiconductor layer exposed through the groove. The method according to claim 1, The insulating layer is located on the first conductivity type semiconductor layer, The extension contact portion includes a first extension contact portion and a second extension contact portion, The first extension contact portion is located along one side of the mesa, and the second extension contact portion is positioned adjacent to one corner of the mesa, and the second extension contact portion is adjacent to the first electrode pad. Light emitting element positioned by. The method according to claim 1, The substrate includes a plurality of modified regions formed on at least one side surface and having a band shape extending in a horizontal direction. And a gap between a bottommost modified area of the modified areas and a bottom surface of the substrate is smaller than a gap between a topmost modified area and the top surface of the substrate.

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