TW201519472A - Light emitting diode having structure for uniform current spreading - Google Patents

Abstract

Provided is a light emitting diode having a uniform current diffusion structure, for increasing external quantum efficiency by preventing current concentration and for preventing localized deterioration or aging and the like. The diode comprises: a first electrode pad arranged on a second semiconductor layer by being spatially separated from a transparent electrode layer positioned on a light emitting structure comprising a first semiconductor layer, an active layer and the second semiconductor layer, and electrically connected, by a connection part, with a first branched electrode extended in a longitudinal direction of the first semiconductor layer; a first blocking layer formed on the light emitting structure so as to electrically insulate the first electrode pad and the connection part from the light emitting structure; on the second semiconductor layer, a second electrode pad for supplying current to the transparent electrode layer and a second branched electrode parallel with the first branched electrode; and a second blocking layer formed on the second semiconductor layer so as to electrically insulate the second electrode pad and the second branched electrode from the second semiconductor layer.

Description

Light-emitting diode with uniform current spreading structure

The present invention relates to a light emitting diode having a p-electrode and an n-electrode, and more particularly to a light-emitting diode capable of preventing a current from being concentrated around the electrode and uniformly diffusing the current to an active layer to improve light efficiency.

A light-emitting diode is an element that converts electrical energy into light, typically produced by at least one active layer between layers doped with impurities of opposite polarity. That is, when a bias voltage is applied to both sides of the active layer, holes and electrons are injected into the active layer to be recombined, thereby generating light.

The light-emitting diode has a higher refractive index than air, and therefore most of the light generated by recombination of electrons and holes remains inside the element. These lights are absorbed by various means such as a film, a substrate, an electrode, etc. before fleeing to the outside, and thus the external quantum efficiency is reduced.

An electrode for biasing an active layer is composed of an electrode pad for packaging and a branch electrode, wherein the branch electrode extends from the electrode sheet to be actually supplied to the active layer bias.

However, due to the current concentration phenomenon generated between the p-electrode and the n-electrode, the current cannot be uniformly dispersed to the entire active layer, and the current is concentrated around the electrode, so that a relatively dark dark portion is formed in a region away from the electrode.

This current concentration phenomenon is particularly likely to occur in a region between the electrode sheet and the branch electrode. The current concentration phenomenon reduces the external quantum efficiency, causing problems such as local deterioration and aging.

On the other hand, such a current concentration phenomenon is often caused by the fact that the pitch between the p-electrode and the n-electrode is not fixed. That is, if the pitch between the electrodes is not fixed, a non-uniform electric field is formed between the electrodes, and thus the current concentration phenomenon is prominent.

It is an object of the present invention to provide a light-emitting diode having a uniform current spreading structure, which blocks current concentration, improves external quantum efficiency, and prevents local deterioration and aging.

A light emitting diode having a uniform current diffusion structure for solving the problem of the present invention includes: a light emitting structure including a first semiconductor layer, an active layer, and a second semiconductor layer; and a transparent electrode layer located in the above light emitting structure Physically. In addition, the method further includes: a first electrode disposed spatially spaced apart from the transparent electrode layer, and including a first branch electrode, a connecting portion, and a first electrode sheet; and a first barrier layer formed on the light emitting structure .

In the light emitting diode of the present invention, the first electrode sheet is disposed on the second semiconductor layer, and is electrically connected to the first branch electrode through a connection portion, wherein the first branch electrode is opposite to the first semiconductor layer Extends in the length direction. The first barrier layer may be formed on the second semiconductor Between the bulk layer and the first electrode sheet described above. Preferably, the first barrier layer is in contact with the first branch electrode. The first barrier layer may have the same shape as or enlarged from the first electrode sheet and the connecting portion. The first barrier layer may be any one selected from an oxide film or a nitride film, or a multilayer film in which the oxide film and the nitride film are stacked.

In a preferred diode of the present invention, the second electrode layer is included on the second semiconductor layer, and may further include a second barrier layer, wherein the second electrode is formed by the second electrode sheet and parallel to the first branch electrode The second branch electrode is configured to electrically insulate the second electrode sheet and the second branch electrode from the second semiconductor layer. The second barrier layer may be formed between the second semiconductor layer and the second electrode sheet.

In a preferred diode of the present invention, a pitch (L1) between the first branch electrode and the second branch electrode is preferably fixed, and the pitch (L1) is a fixed area preferably occupies 60% of the entire area. the above. The second barrier layer may have the same shape as or enlarged from the second electrode sheet and the second branch electrode. The second barrier layer of the present invention may be any one selected from an oxide film or a nitride film, or a multilayer film in which the above oxide film and the nitride film are laminated. The second barrier layer formed on the second electrode sheet and the transparent electrode layer may be spatially separated by a blocking groove for exposing the second semiconductor layer.

According to the light-emitting diode of the present invention having a uniform current-diffusion structure, by additionally preventing a structure in which current is diffused to the first electrode sheet and the second electrode sheet, current concentration is blocked to improve external quantum efficiency, and local deterioration can be prevented. Aging and so on. By preventing the current from diffusing, the current is prevented from being concentrated between the electrode sheet and the branch electrode, so that the light-emitting diode can flow evenly. Current. Further, by making the pitch between the electrodes through which the current flows, it is possible to prevent occurrence of an unintended current concentration phenomenon between the electrodes.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments described below can be modified into various other ways, and the scope of the present invention is not limited to the embodiments described below. The embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art.

Embodiments of the present invention provide a light-emitting diode having a uniform current spreading structure, and a structure for preventing current diffusion is added to the electrode sheet, thereby blocking current concentration phenomenon to improve external quantum efficiency, preventing local deterioration, aging, and the like. For this reason, a light-emitting diode having a structure for preventing current diffusion in the electrode sheet is observed in detail, and the process of blocking the current concentration phenomenon will be specifically described. In addition, a description will be given of a process in which the interval between the electrodes through which the current flows due to the current diffusion preventing structure according to the embodiment of the present invention becomes a fixed process. Here, the current concentration focusing means that the current concentrates between the electrode sheet and the branch electrode due to the current diffusion in the electrode sheet, so that a uniform current does not flow through the entire light emitting diode.

1 is a perspective view of a light-emitting diode having a uniform current diffusion structure according to an embodiment of the present invention; FIG. 2 is a cross-sectional view taken along line II-II of FIG. 1; A cross-sectional view taken along line III-III; and Fig. 4 is a cross-sectional view taken along line IV-IV of Fig. 1.

Referring to FIGS. 1 through 4, the light emitting diode includes: a substrate 10, a light emitting structure 14 on one side of the substrate 10, a transparent electrode layer 20, a first electrode 30, a second electrode 40, and a first barrier layer 34. And a second barrier layer 44. In this case, the first barrier layer 34 is used to block current from the first electrode The first electrode sheet 31 of 30 is diffused; the second barrier layer 44 serves to block current from diffusing from the second electrode sheet 41 of the second electrode 40. The first barrier layer 34 and the second barrier layer 44 are both disposed on the light emitting structure 14 via the transparent electrode layer 20.

The substrate 10 may be sapphire (Al2O3), tantalum carbide (SiC), gallium nitride (GaN), gallium arsenide (GaAs), germanium (Si), germanium (Ge), zinc oxide (ZnO), magnesium oxide (MgO). Any one of aluminum nitride (AlN), boron nitride (BN), gallium phosphide (GaP), indium phosphide (InP), and lithium-aluminum oxide (LiAl 2 O 3 ). A concavo-convex pattern (not shown) capable of reflecting light may be formed on the upper surface, the lower surface of the substrate 10, or both surfaces of the upper surface and the lower surface. A buffer layer 12 may be formed between the substrate 10 and the light emitting structure 14, and the buffer layer 12 serves to alleviate lattice mismatch. The buffer layer 12 may be formed as a single layer or a plurality of layers, and may be composed of, for example, at least one of GaN, InN, AlN, InGaN, AlGaN, AlGaInN, and AlInN.

The light emitting structure 14 may be located on the substrate 10 or on the buffer layer 12. The structure of the light-emitting structure 14 is any one of an np junction structure, a pn junction structure, an npn junction structure, and a pnp junction structure in which a plurality of conductive semiconductor layers are based on the substrate 10.

The light emitting structure 14 includes a first semiconductor layer 15, a active layer 16, and a second semiconductor layer 17 which are sequentially stacked. For example, in the case of an np junction structure, the first semiconductor layer 15 refers to an n-type semiconductor layer, and the second semiconductor layer 17 refers to a p-type semiconductor layer.

When a positive direction bias is applied to the light-emitting structure 14, the electrons in the conduction band of the active layer 16 and the holes in the Valence band migrate and recombine, thereby forming an energy gap. A considerable amount of energy is emitted for the light. At this time, the wavelength of the emitted light is determined according to the kind of the substance constituting the active layer 16. The electrons or holes of the active layer 16 are supplied from the first semiconductor layer 15 and the second semiconductor layer 17 in accordance with the applied bias voltage.

The first semiconductor layer 15 and the second semiconductor layer 17 may contain mutually different impurities in order to have mutually different conductivity types. For example, the first semiconductor layer 15 may include an n-type impurity, and the second semiconductor layer 17 may include a p-type impurity. In this case, the first semiconductor layer 15 supplies electrons, and the second semiconductor layer 17 provides holes. Of course, the case where the first semiconductor layer 15 is p-type and the second semiconductor layer 17 is n-type is also feasible within the scope of the present invention. The first semiconductor layer 15 and the second semiconductor layer 17 may respectively include a group III-V compound such as gallium nitride (GaN).

In the case where the light emitting structure 14 is an np junction structure, the first semiconductor layer 15 may include n-type Al _x In _y Ga _z N doped with an n-type impurity (0) x,y,z 1, x + y + z = 1), n-type GaN, and the like. In this case, the n-type impurity may be at least one selected from the group consisting of bismuth (Si), germanium (Ge), tin (Sn), selenium (Se), and tellurium (Te). The second semiconductor layer may use p-type Al _x In _y Ga _z N (0) doped with a p-type impurity x,y,z 1, x + y + z = 1), p-type GaN, and the like. The p-type impurity may be at least one selected from the group consisting of magnesium (Mg), zinc (Zn), calcium (Ca), strontium (Sr), bismuth (Be), and barium (Ba).

The active layer 16 has a lower energy band gap than the first semiconductor layer 15 and the second semiconductor layer 17, and thus is capable of exciting light. The active layer 16 can emit light of various wavelengths, for example, can emit infrared rays, visible light, or ultraviolet rays.

The active layer 16 may include a group III-V compound and may include Al _x In _y Ga _z N (0 x,y,z 1, x + y + z = 1), InGaN or AlGaN. In addition, the active layer 16 may be a single quantum well (SQW) or a multiple quantum well (Multi Quantum Well: MQW). Further, the active layer 16 may have a stacked structure of a quantum well layer and a quantum barrier layer, and the number of the quantum well layer and the quantum barrier layer may be variously changed as needed. In addition, the active layer 16 may be a structure of GaN/InGaN/GaN MQW or a structure of GaN/AlGaN/GaN MQW. However, this is merely an example, and the wavelength of light emitted from the active layer 16 differs depending on the constituent material.

The light emitting structure 14 may be in the shape of a side wall having a partial region in which the active layer 16 and the second semiconductor layer 17 are removed, and correspondingly, a portion of the first semiconductor layer 15 is removed and exposed. The first branch electrode 33 of the first electrode 30 according to the embodiment of the present invention extends in the longitudinal direction on the region where the portion of the first semiconductor layer 15 is exposed by the above-described sidewall structure. Thereby, the active layer 16 can be limited to the above-described side wall structure to emit light. The sidewall structure may be formed by inductively coupled plasma reactive ion etching (ICP-RIE), wet etching, or dry etching.

The transparent electrode layer 20 is composed of a transparent and electrically conductive material and is located on the second semiconductor layer 17. The transparent electrode layer 20 functions to uniformly disperse the current injected from the second electrode 40 to the second semiconductor layer 17. The transparent electrode 20 may include a metal such as a composite layer of nickel (Ni) and gold (Au). In addition, the transparent electrode layer 20 may include an oxide, for example, ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), IZTO (Indium Zinc Tin Oxide), AZO (Aluminum Zinc Oxide), IAZO (Indium Aluminum Zinc Oxide). , GZO (Gallium Zinc Oxide), IGO (Indium Gallium Oxide), IGZO (Indium Gallium Zinc Oxide), IGTO (Indium Gallium Tin Oxide), ATO (Aluminum Tin Oxide), IWO (Indium Tungsten Oxide), CIO (Cupper Indium Oxide) And MIO (Magnesium Indium Oxide), at least one of MgO, ZnO, In ₂ O ₃ , TiTaO ₂ , TiNbO ₂ , TiO _x , RuO _{x ,} and IrO _x .

The first electrode 30 according to the embodiment of the present invention is a structure for supplying a current to the first semiconductor layer 15. The first electrode 30 includes a first electrode sheet 31, a connecting portion 32, and a first branch electric Formed by pole 33. The first electrode sheet 31 is located on the second semiconductor layer 17, and the first branch electrode 33 extends in the longitudinal direction on the exposed region of the first semiconductor layer 15. The first electrode sheet 31 and the transparent electrode layer 20 are spaced apart from each other. The connecting portion 32 connects the first electrode sheet 31 and the first branch electrode 33 by the above-described side wall structure. Thereby, the first electrode piece 31 and the first branch electrode 33 have at least a height difference corresponding to the above-described side wall.

The first electrode sheet 31 is used for package bonding, and the manner thereof is not limited, but is preferably a disk shape. The connecting portion 32 may be elongated in a partial region of the first electrode sheet 31, and the first branch electrode 33 is also preferably elongated. The first electrode 30 can be fabricated by wet etching or dry etching. On the other hand, as shown in the drawing, the connecting portion 32 may be formed on the groove formed on the side wall.

The first barrier layer 34 according to an embodiment of the present invention is for preventing current diffusion in the first electrode sheet 31. To this end, the first barrier layer 34 is inserted into the region between the first electrode sheet 31 and the second semiconductor layer 17 in the same or slightly enlarged shape as the first electrode sheet 31 and the connecting portion 32, and the connecting portion 32 and the above-mentioned side wall The area between. Here, the reason why the first barrier layer 34 is formed on the connection portion 32 is to prevent an unnecessary current from flowing in the light-emitting structure 14. Therefore, the first barrier layer 34 of the connection portion 32 has to be performed in order to block the current in the first electrode sheet 31. The first barrier layer 34 blocks a phenomenon in which current introduced from the first electrode sheet 31 flows through the transparent electrode layer 20 to cause current concentration. The current of the introduced first electrode sheet 31 is injected into the first semiconductor layer 15 only by the first branch electrode 33 due to the first barrier layer 34. Thereby, the current concentration phenomenon between the first electrode sheet 31 and the second branch electrode 42 of the second electrode 40 can be prevented. At this time, the first barrier layer 34 is preferably in contact with the first branch electrode 33.

The first barrier layer 34 may be opaque or transparent and may be an insulator such as an oxide. The first barrier layer 34 may be an oxide or a nitrogen such as cerium oxide, cerium nitride, germanium oxynitride or the like. Compound. In addition, the first barrier layer 34 may be a multilayer film in which the above oxide or nitride is laminated. The material constituting the first barrier layer 34 exemplified herein is merely illustrative, and is not necessarily limited thereto. The first barrier layer 34 may be formed by wet etching or dry etching. The thickness of the first barrier layer 34 can be set in advance in consideration of the type of the insulator and the degree of blocking current.

The second electrode 40 according to the embodiment of the present invention is a structure for supplying a current to the second semiconductor layer 17. The second electrode 40 is formed by including a second electrode sheet 41 and a second branch electrode 42. The second electrode sheet 41 is located on the second semiconductor layer 17, and the second branch electrode 42 extends on the second semiconductor layer 17 in parallel with the first branch electrode 33. The second electrode sheet 41 is used for package bonding, and its shape is not limited, but is preferably a disk shape. The second branch electrode 42 is preferably elongated in parallel with the first branch electrode 33. The second electrode 40 may be formed by wet etching or dry etching.

On the other hand, the parallel first branch electrodes 33 and the second branch electrodes 43 are preferable modes for preventing current concentration due to current spreading. The first branch electrode 33 and the second branch electrode 41 may be deformed into various shapes according to the shape and use of the light emitting diode, and the first branch electrode 33 and the second branch electrode 42 may not necessarily be parallel. However, if the first branch electrode 33 and the second branch electrode 42 are not parallel, the interval between the electrodes 33 and 42 differs depending on the position, resulting in a phenomenon of current concentration. Therefore, the first branch is preferably the same as the embodiment of the present invention. The electrode 33 and the second branch electrode 42 are parallel.

The first electrode 30 and the second electrode 40 may each be composed of the same substance and can be realized by one process. The first electrode 30 and the second electrode 40 may include, for example, gold (Au), silver (Ag), aluminum (Al), palladium (Pd), titanium (Ti), chromium (Cr), nickel (Ni), tin (Sn ), chromium (Cr), platinum (Pt), tungsten (W), cobalt (Co), iridium (Ir), ruthenium (Rh), ruthenium (Ru), zinc (Zn), manganese (Mg) or alloys thereof . For example, carbon nanometers can be included tube. The second electrode 40 may be composed of a single layer or a plurality of layers, and may be composed of, for example, a multilayer such as Ti/Al, Cr/Au, Ti/Au, or Au/Sn.

The second barrier layer 44 according to an embodiment of the present invention includes a second electrode sheet barrier layer 45 and a second branch electrode barrier layer 46. The second electrode sheet barrier layer 45 is located between the second electrode sheet 41 and the second semiconductor layer 17, and is preferably slightly enlarged compared to the second electrode sheet 41. The second electrode sheet barrier layer 45 prevents electrification to the second semiconductor layer 17. Further, a blocking groove 48 may be provided between the second electrode sheet barrier layer 45 and the transparent electrode 20, and the blocking groove 48 forms a space for exposing the second semiconductor layer 17. The current introduced from the second electrode sheet 41 flows to the transparent electrode layer 20 more reliably by the blocking groove 48.

The second branch electrode barrier layer 46 is located on the transparent electrode layer 20 and is disposed at an upper portion of the second semiconductor layer 17 and a lower portion of the second branch electrode 42. The second branch electrode barrier layer 46 is preferably slightly enlarged in shape compared to the second branch electrode 42. In addition, the second branch electrode barrier layer 46 causes current not to flow to the second semiconductor layer 17 but only to the transparent electrode layer 20. In other words, the current of the introduced second electrode sheet 41 is dispersed to the transparent electrode 20 only by the second branch electrode 42 due to the second barrier layer 44, thereby being injected into the second semiconductor layer 17.

The second barrier layer 44 may be opaque or transparent and may be an insulator such as an oxide. The second barrier layer 44 may be an oxide or a nitride such as tantalum oxide, tantalum nitride, niobium oxynitride or the like. Further, the second barrier layer 44 may be a multilayer film in which the above oxide or nitride is laminated. The material constituting the second barrier layer 44 exemplified herein is merely illustrative and is not necessarily limited thereto. The second barrier layer 44 may be formed by wet etching or dry etching. The thickness of the second barrier layer 44 can be set in advance in consideration of the type of the insulator and the degree of blocking current.

The light emitting diode according to the embodiment of the present invention can bring about the effect that the first branch electrode 33 and the second branch electrode 44 are made by the second branch electrode 42 through the first barrier layer 34 and the second barrier layer 44. The gap between them is set to be fixed. In the case of the first barrier layer 34, since the current flow with the second branch electrode 42 is blocked, the distance L1 from the first branch electrode 33 through which the current actually flows to the second branch electrode 42 can be made. Evenly. In other words, if the first barrier layer 34 is not present, the interval (not shown) between the first electrode sheet 31 and the second branch electrode 42 is smaller than the above-described distance L1, and thus current concentration may occur. However, if the first barrier layer 34 is provided and the first electrode sheet 31 is electrically insulated as in the embodiment of the present invention, the current concentration phenomenon between the first electrode sheet 31 and the second branch electrode 42 can be blocked. On the other hand, the area where the interval L1 is fixed is preferably 60% or more of the entire area. When the above area is 60% or less, the current applied to the entire wafer is concentrated to a portion having a fixed interval, thereby reducing the current dispersion effect.

Similarly, the distance L2 between the second electrode sheet 41 and the first branch electrode 33 is smaller than the distance L1 between the first branch electrode 33 and the second branch electrode 42, so if there is no second barrier layer 44, it may be caused as described above. The phenomenon of current concentration. However, as in the embodiment of the present invention, if the second electrode sheet 41 is electrically insulated by providing the second barrier layer 44, current concentration between the second electrode sheet 41 and the first branch electrode 33 can be blocked. . As described above, the first barrier layer 34 and the second barrier layer 44 of the present invention cause the currents introduced to the first electrode sheet 31 and the second electrode sheet 41 to align only the first branch electrode 33 and the second branch electrode in parallel, respectively. 42 passed. Thereby, it is possible to prevent a phenomenon in which current is concentrated between the first electrode sheet 31 and the second branch electrode 42 and between the second electrode sheet 41 and the first branch electrode 33.

Fig. 5a is a photograph showing a light-emitting image of a conventional light-emitting diode without a barrier layer, and Fig. 5b is a photograph of a light-emitting image of a light-emitting diode according to an embodiment of the present invention having a barrier layer.

Referring to Figures 5a and 5b, the conventional light-emitting diode light output (PO) is 100%, the light output of the present invention is 101.5%, and the light output is increased by 1.5%. Further, the positive direction of the conventional light-emitting diode voltage V _F is 2.90V, the positive direction of the light emitting diode of the present invention is 2.84V voltage V _F, forward voltage V _F is reduced 0.06V. The existing light-emitting diode generates a current concentration phenomenon between the electrode sheet and the branch electrode, and forms a relatively dark dark portion in a region far from the electrode. In contrast, the light-emitting diode of the present invention has relatively little dark portion formed relatively, and it can be seen that the current is uniformly dispersed.

When a current concentration phenomenon occurs and the current is not uniformly dispersed, the light output is lowered and the positive direction voltage V _{F is} increased as compared with the opposite case. Thus, the conventional light-emitting diode that does not block the current concentration phenomenon has a smaller light output and a higher forward voltage V _F than the diode of the present invention. As described above, the embodiment of the present invention prevents the current concentration phenomenon by providing the first barrier layer 34 and the second barrier layer 44 on the first electrode sheet 31 and the second electrode sheet 41, respectively, thereby improving the light-emitting diode The light output of the body reduces the positive direction voltage V _F .

Fig. 6 is a plan view showing a modification of the light-emitting diode having the uniform current diffusion structure according to the present invention.

Referring to Fig. 6, in a modification of the present invention, a first pitch electrode 33a extending between the pair of second branch electrodes 42a toward the first barrier layer 34a and the first electrode sheet 31a is formed at a fixed pitch, The pair of second branch electrodes 42a are electrodes that branch from the second electrode sheet 41a on the second barrier layer 44a to both sides of the transparent electrode layer 20a. The second barrier layer 44a and the second electrode sheet 41a are connected to the second branch electrode 42a. The transparent electrode layer 20a is located on the second semiconductor layer 17a. Therefore, the second barrier layer 44a, the second electrode sheet 41a, and the pair of second branch electrodes 42a form a "ㄈ" shape.

The functions and functions of the first barrier layer 34a and the second barrier layer 44a of the above-described modification are the same as those of the first barrier layer 34 and the second barrier layer 44 described with reference to FIGS. 1 to 5b. That is, the first barrier layer 34a and the second barrier layer 44a cause currents introduced to the first electrode sheet 31a and the second electrode sheet 41a to flow only to the first branch electrode 33a and the second branch electrode 42a which are arranged in parallel. Thereby, it is possible to prevent a phenomenon in which current concentration occurs between the first electrode piece 31a and the second branch electrode 42a and between the second electrode piece 41a and the first branch electrode 33a.

Fig. 7 is a plan view showing another modification of the light-emitting diode having the uniform current diffusion structure according to the present invention.

Referring to Fig. 7, in another modification of the present invention, the second barrier layer 44b, the second electrode sheet 41b, the pair of second branch electrodes 42b, and the first branch electrode 33b are the same as in Fig. 6, but the first barrier layer 34b And the first electrode sheet 31b is expanded toward the outer surface of the diode. The functions and functions of the first barrier layer 34b and the second barrier layer 44b according to another modification of the present invention are the same as those of the first barrier layer 34 and the second barrier layer 44 described with reference to FIGS. 1 to 5b. That is, the first barrier layer 34b and the second barrier layer 44b respectively flow currents introduced to the first electrode piece 31b and the second electrode piece 41b only to the first branch electrode 33b and the second branch electrode 42b which are arranged in parallel. Thereby, it is possible to prevent a current concentration phenomenon occurring between the first electrode piece 31b and the second branch electrode 42b and the second electrode piece 41b and the first branch electrode 33b.

The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the above-described embodiments, and those having ordinary skill in the art can perform various kinds within the scope of the technical idea of the present invention. Deformation.

10‧‧‧Substrate

12‧‧‧ Buffer layer

14‧‧‧Lighting structure

15‧‧‧First semiconductor layer

16‧‧‧Active layer

17‧‧‧Second semiconductor layer

20‧‧‧Transparent electrode layer

30‧‧‧First electrode

31, 31a, 31b‧‧‧ first electrode

32‧‧‧Connecting Department

33, 33a, 33b‧‧‧ first branch electrode

34, 34a, 34b‧‧‧ first barrier

40‧‧‧second electrode

41, 41a, 41b‧‧‧ second electrode

42:, 42a, 42b‧‧‧ second branch electrode

44, 44a, 44b‧‧‧ second barrier

45‧‧‧Second electrode sheet barrier

46‧‧‧Second branch electrode barrier

48‧‧‧blocking slot

Fig. 1 is a perspective view showing a light-emitting diode having a uniform current spreading structure according to the present invention.

Fig. 2 is a cross-sectional view taken along line II-II of Fig. 1;

Fig. 3 is a cross-sectional view taken along line III-III of Fig. 1;

Fig. 4 is a cross-sectional view taken along line IV-IV of Fig. 1;

Fig. 5a is a photograph showing a light-emitting image of a conventional light-emitting diode without a barrier layer; and Fig. 5b is a photograph of a light-emitting image of a light-emitting diode according to an embodiment of the present invention having a barrier layer.

Fig. 6 is a plan view showing a modification of the light-emitting diode having the uniform current diffusion structure according to the present invention.

Fig. 7 is a plan view showing another modification of the light-emitting diode having the uniform current diffusion structure according to the present invention.

10‧‧‧Substrate

12‧‧‧ Buffer layer

14‧‧‧Lighting structure

15‧‧‧First semiconductor layer

16‧‧‧Active layer

17‧‧‧Second semiconductor layer

20‧‧‧Transparent electrode layer

30‧‧‧First electrode

31‧‧‧First electrode sheet

32‧‧‧Connecting Department

33‧‧‧First branch electrode

34‧‧‧First barrier

40‧‧‧second electrode

41‧‧‧Second electrode

42‧‧‧Second branch electrode

44‧‧‧second barrier

45‧‧‧Second electrode sheet barrier

46‧‧‧Second branch electrode barrier

48‧‧‧blocking slot

Claims (14)

A light emitting diode having a uniform current diffusion structure, comprising: a light emitting structure comprising a first semiconductor layer, an active layer and a second semiconductor layer; a transparent electrode layer on the light emitting structure; a first electrode; The transparent electrode layers are spaced apart from each other, and include a first branch electrode, a connection portion, and a first electrode sheet; and a first barrier layer formed on the light-emitting structure. The light emitting diode according to claim 1, wherein the first electrode sheet is provided on the second semiconductor layer, and is electrically connected to the first branch electrode through the connecting portion. The first branch electrode extends in the longitudinal direction of the first semiconductor layer. A light-emitting diode having a uniform current diffusion structure according to claim 1, wherein the first barrier layer is formed between the second semiconductor layer and the first electrode sheet. A light-emitting diode having a uniform current spreading structure according to claim 1, wherein the first barrier layer and the first branch electrode are in contact with each other. A light emitting diode having a uniform current spreading structure according to claim 1, wherein the first barrier layer has the same shape as the first electrode sheet and the connecting portion or Expanded shape. A light-emitting diode having a uniform current diffusion structure according to claim 1, wherein the first barrier layer is any one selected from an oxide film or a nitride film, or the above oxide film and the above A multilayer film in which a nitride film is laminated. A light emitting diode having a uniform current spreading structure according to claim 1, wherein the second semiconductor layer includes a second electrode, further comprising a second barrier layer, wherein the second electrode is a second electrode sheet and a second branch electrode parallel to the first branch electrode, wherein the second barrier layer is for electrically insulating the second electrode sheet and the second branch electrode from the second semiconductor layer. A light-emitting diode having a uniform current diffusion structure according to claim 7, wherein the second barrier layer is formed between the second semiconductor layer and the second electrode sheet. A light-emitting diode having a uniform current spreading structure according to claim 7, wherein a pitch (L1) between the first branch electrode and the second branch electrode is fixed. A light-emitting diode having a uniform current spreading structure according to claim 9, wherein the pitch (L1) is a fixed area of 60% or more of the entire area. A light-emitting diode having a uniform current spreading structure according to claim 7, wherein the second barrier layer has the same shape as or enlarged from the second electrode sheet and the second branch electrode. A light-emitting diode having a uniform current diffusion structure according to claim 7, wherein the second barrier layer has the same shape as or enlarged from the second branch electrode. A light-emitting diode having a uniform current diffusion structure according to claim 7, wherein the second barrier layer is a selected one of an oxide film or a nitride film, or the oxide film and the nitrogen A multilayer film in which a compound film is laminated. The light emitting diode having a uniform current spreading structure according to claim 7, wherein the second barrier layer formed on the second electrode sheet and the transparent electrode layer are spatially separated by a blocking groove The blocking groove is for exposing the second semiconductor layer.