Light emitting diode and light emitting device

Abstract

The invention relates to a light emitting diode and a light emitting device. The light-emitting diode comprises a semiconductor laminated layer which comprises a first semiconductor layer, a light-emitting layer and a second semiconductor layer which are sequentially laminated from bottom to top; the transparent conductive layer is formed on the second semiconductor layer; the protective layer is formed on the transparent conductive layer; the second electrode is formed on the protection layer and comprises a bonding pad part and an extension part; the protective layer forms a first opening and a second opening in the bonding pad part and the extension part of the second electrode respectively, and the second electrode is electrically connected with the second semiconductor layer through the first opening and the second opening; the packaging structure is characterized in that the second opening of the protection layer comprises a plurality of first opening parts and a second opening part, the second opening part is formed at the tail end far away from the second electrode bonding pad part, and the size of the second opening part is larger than that of the first opening part. According to the invention, size differentiation design is carried out on the second opening of the protection layer in the second electrode extension part, so that the reliability of the chip is improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to a light emitting diode and a light emitting device. Background Art

[0002] Light Emitting Diode (LED) is usually made of semiconductors such as GaN, GaAs, GaP, GaAsP, etc. Its core is a PN junction with luminous properties. Under forward voltage, electrons are injected from the N region into the P region, and holes are injected from the P region into the N region. Some of the minority carriers that enter the other region recombine with the majority carriers to emit light. LED has the advantages of high luminous intensity, high efficiency, small size, and long service life, and is considered to be one of the most promising light sources at present.

[0003] The early GaN LED chip manufacturing process includes four processes, namely, table etching (MESA), making a transparent conductive layer (such as ITO), making electrodes, and making a protective layer. In recent years, in order to improve the luminous efficiency of light-emitting diodes, it is known that there are four new processes in the industry, namely, table etching (MESA), making a transparent conductive layer, making electrodes, and making a protective layer. At present, in the LED industry, in order to achieve effective current expansion, multiple extended electrode designs are generally adopted. Since the end of the extended electrode is often a high current density area, in this new four-step process, the end of the extended electrode is often prone to ESD explosion points and burns due to excessive charge concentration, which in turn causes chip failure and dead light. Therefore, how to further optimize the design of the protective layer to improve the reliability of the light-emitting diode chip is a technical problem that technicians in this field need to solve. Summary of the invention

[0004] In view of the defects and shortcomings of light-emitting diodes in the prior art, the present application provides a light-emitting diode and a light-emitting device to improve the reliability of the chip.

[0005] One embodiment of the present invention provides a light emitting diode, which at least comprises: The semiconductor stack comprises, from bottom to top, a first semiconductor layer, a light-emitting layer, and a second semiconductor layer stacked in sequence; A transparent conductive layer is formed on the second semiconductor layer; A protective layer formed on the transparent conductive layer; A second electrode is formed on the protective layer and includes a pad portion and an extension portion; The protective layer forms a first opening and a second opening at the pad portion and the extension portion of the second electrode, respectively, to expose a portion of the upper surface of the second semiconductor layer located at the second electrode pad portion and a portion of the upper surface of the transparent conductive layer located at the second electrode extension portion, and the second electrode is electrically connected to the second semiconductor layer through the first opening and the second opening; The characteristic is that the second opening of the protective layer includes a plurality of first openings and at least one second opening, the second opening is formed at the end away from the second electrode pad, and the size of the second opening is larger than that of the first opening.

[0006] According to another embodiment of the present invention, a light emitting device is provided, which adopts the light emitting diode described in any of the above embodiments.

[0007] The light-emitting diode provided by the present invention is designed with differentiated sizes of the second opening of the second electrode extension portion where the protective layer is located, specifically by increasing the size of the second opening portion located at the end of the second electrode extension portion away from the second electrode pad portion. On the one hand, it can avoid the occurrence of ESD explosion points due to excessive charge concentration at the end of the extended electrode, thereby improving the chip's anti-static impact capability and ensuring the reliability of the light-emitting diode; on the other hand, it can also allow the current at the end of the extended electrode to spread as evenly as possible to the surroundings through the large-sized second opening portion, thereby improving the overall current uniformity of the light-emitting diode, and thereby improving the luminous efficiency of the light-emitting diode chip.

[0008] Other features and advantages of the present invention will be set forth in the following description, and in part will be apparent from the description, or may be learned by practicing the present invention.

[0009] In view of the defects and shortcomings of light-emitting diodes in the prior art, the present application provides a light-emitting diode and a light-emitting device to improve the reliability of the chip.

[0010] One embodiment of the present invention provides a light emitting diode, which at least comprises: The semiconductor stack comprises, from bottom to top, a first semiconductor layer, a light-emitting layer, and a second semiconductor layer stacked in sequence; A transparent conductive layer is formed on the second semiconductor layer; A protective layer formed on the transparent conductive layer; A second electrode is formed on the protective layer and includes a pad portion and an extension portion; The protective layer forms a first opening and a second opening at the pad portion and the extension portion of the second electrode, respectively, to expose a portion of the upper surface of the second semiconductor layer located at the second electrode pad portion and a portion of the upper surface of the transparent conductive layer located at the second electrode extension portion, and the second electrode is electrically connected to the second semiconductor layer through the first opening and the second opening; The characteristic is that the second opening of the protective layer includes a plurality of first openings and at least one second opening, the second opening is formed at the end away from the second electrode pad, and the size of the second opening is larger than that of the first opening.

[0011] According to another embodiment of the present invention, a light emitting device is provided, which adopts the light emitting diode described in any of the above embodiments.

[0012] The light-emitting diode provided by the present invention is designed with differentiated sizes of the second opening of the second electrode extension portion where the protective layer is located, specifically by increasing the size of the second opening portion located at the end of the second electrode extension portion away from the second electrode pad portion. On the one hand, it can avoid the occurrence of ESD explosion points due to excessive charge concentration at the end of the extended electrode, thereby improving the chip's anti-static impact capability and ensuring the reliability of the light-emitting diode; on the other hand, it can also allow the current at the end of the extended electrode to spread as evenly as possible to the surroundings through the large-sized second opening portion, thereby improving the overall current uniformity of the light-emitting diode, and thereby improving the luminous efficiency of the light-emitting diode chip.

[0013] Other features and advantages of the present invention will be set forth in the following description, and in part will be apparent from the description, or may be learned by practicing the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0015] Figure 1 A schematic top view of a light emitting diode provided in Embodiment 1 of the present invention; Figure 2 For along Figure 1 A schematic diagram of the cross-sectional structure of the A-A' line; Figure 3 For Figure 2 A local enlarged schematic diagram of the box area; Figure 4 For along Figure 1 Schematic diagram of the cross-sectional structure of the BB' line; Figure 5 A light mask diagram for making a light emitting diode provided by the present invention; Figure 6 A schematic diagram of a current flow path of a light emitting diode provided by the present invention; Figure 7 A schematic top view of a light emitting diode provided in the second embodiment of the present invention; Figure 8 For along Figure 7 A schematic diagram of the cross-sectional structure of the A-A' line; Fig. 9A schematic top view of a light emitting diode provided in Embodiment 3 of the present invention; Fig.10 For along Fig. 9 A schematic diagram of the cross-sectional structure of the A-A' line; Fig.11 A schematic top view of a light emitting diode provided in Embodiment 4 of the present invention; Fig.12 For along Fig.11 A schematic diagram of the cross-sectional structure of the A-A' line; Fig.13 A schematic top view of another light emitting diode provided in the fourth embodiment of the present invention; Fig.14 For along Fig.13 A schematic diagram of the cross-sectional structure of the A-A' line; Fig.15 A schematic top view of another light emitting diode provided in the fourth embodiment of the present invention; Fig.16 For along Fig.15 A schematic diagram of the cross-sectional structure of the A-A' line; Fig.17 A schematic top view of another light emitting diode provided in the fourth embodiment of the present invention; Fig.18 For along Fig.17 Schematic diagram of the cross-sectional structure along the A-A' line.

[0016] Reference numerals: 10-substrate; 12-semiconductor stack; 123-first semiconductor layer; 124-light-emitting layer; 125-second semiconductor layer; 14-insulating layer; 16-transparent conductive layer; 18-protective layer; 21-first electrode; 211-first electrode pad portion; 212-first electrode extension portion; 22-second electrode; 221-second electrode pad portion; 222-second electrode extension portion; 2221-first end of the second electrode extension portion; 2222-second end of the second electrode extension portion; 2220-end of the second electrode extension portion; 31-first opening; 310-antenna; 32-second opening; 321-first opening portion; 322-second opening portion; 33-third opening; 34 fourth opening; 35-fifth opening; 36-sixth opening; 40-through hole. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention; the technical features designed in different implementation modes of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0018] The present invention provides a light emitting diode, which at least comprises: The semiconductor stack comprises, from bottom to top, a first semiconductor layer, a light-emitting layer, and a second semiconductor layer stacked in sequence; A transparent conductive layer is formed on the second semiconductor layer; A protective layer formed on the transparent conductive layer; A second electrode is formed on the protective layer and includes a pad portion and an extension portion; The protective layer forms a first opening and a second opening at the pad portion and the extension portion of the second electrode, respectively, to expose a portion of the upper surface of the second semiconductor layer located at the second electrode pad portion and a portion of the upper surface of the transparent conductive layer located at the second electrode extension portion, and the second electrode is electrically connected to the second semiconductor layer through the first opening and the second opening; The characteristic is that the second opening of the protective layer includes a plurality of first openings and at least one second opening, the second opening is formed at the end away from the second electrode pad, and the size of the second opening is larger than that of the first opening.

[0019] The present invention designs the size of the second opening of the protective layer located in the second electrode extension portion to be differentiated, specifically, to increase the size of the second opening located at the end of the second electrode extension portion away from the second electrode pad portion. On the one hand, it can avoid the occurrence of ESD explosion points due to excessive charge concentration at the end of the extended electrode, thereby improving the chip's anti-static impact capability and further ensuring the reliability of the light-emitting diode; on the other hand, it can also allow the current at the end of the extended electrode to spread as evenly as possible through the large-sized second opening portion to avoid direct injection of current at the end of the extended electrode, promote lateral expansion of current, improve the overall current uniformity of the light-emitting diode, and further improve the luminous efficiency of the light-emitting diode chip.

[0020] In one embodiment, the second electrode extension has a first end connected to the second electrode pad and a second end away from the second electrode pad, and the second opening is formed below the second end of the second electrode extension. Since the second end of the second electrode extension is often a high current density area, by setting the second opening with the largest size in the high current density area, it is possible to prevent ESD explosion points from occurring in this area due to excessive charge concentration, thereby improving the reliability of the light-emitting diode chip.

[0021] In one embodiment, the sizes of the plurality of first openings are the same.

[0022] In one embodiment, the sizes of the first openings increase in sequence along the extension direction gradually away from the second electrode pad portion. In the present invention, the sizes of the first openings may be the same or different. Since the current density will gradually increase along the extension direction of the second electrode extension portion, in some preferred embodiments, the design that the sizes of the first openings increase in sequence along the extension direction of the second electrode extension portion can prevent ESD explosion points from occurring in areas with high current density, such as near the end of the extension electrode, due to excessive charge concentration; at the same time, it can also alleviate the current congestion effect on the second electrode, improve the overall current uniformity of the light-emitting diode, and thus improve the reliability and luminous efficiency of the light-emitting diode chip.

[0023] In one embodiment, the size of the second opening is at least twice the size of the first opening. By limiting the ratio of the size of the second opening to the size of the first opening, the current can be more effectively diffused to the surroundings through the large-sized second opening, avoiding ESD explosion points caused by charge concentration, and improving the overall current uniformity of the light-emitting diode, thereby improving the reliability and luminous efficiency of the light-emitting diode chip.

[0024] In one embodiment, the size of the second opening is a multiple of the size of the first opening in a range of 2 to 20. By further limiting the multiple of the size of the second opening to the size of the first opening, the current is further promoted to be more effectively diffused to the surroundings through the large-sized second opening at the end of the extended electrode, thereby further improving the overall performance of the LED.

[0025] In one embodiment, there are intervals between the second openings, and the sizes of the intervals are the same.

[0026] In one embodiment, there is a gap between the second openings, and the size of the gap decreases gradually along the extension direction away from the second electrode pad portion. In the present invention, the gaps between the second openings can be the same or different. Since the current density will gradually increase along the extension direction of the second electrode extension portion, in some preferred embodiments, the design of the gaps between the second openings decreasing gradually along the extension direction of the second electrode extension portion can also prevent the occurrence of ESD explosion points in areas with high current density due to excessive charge concentration; at the same time, it can also alleviate the current congestion effect on the second electrode, improve the overall current uniformity of the light-emitting diode, and thus improve the reliability and luminous efficiency of the light-emitting diode chip.

[0027] In one embodiment, the second opening portion and the second electrode extension portion have an overlapping portion, and the length of the overlapping portion is 2% to 40% of the length of the second electrode extension portion.

[0028] In one embodiment, the second opening portion and the second electrode extension portion have an overlapping portion, and an area of ​​the overlapping portion is 2% to 40% of an area of ​​the second electrode extension portion.

[0029] The length or area ratio of the overlapping part between the second opening and the second electrode extension portion can further promote the current to diffuse more evenly around through the large-sized second opening, thereby improving the overall current uniformity on the second electrode and further improving the luminous efficiency of the light-emitting diode chip.

[0030] In one embodiment, the light emitting diode further includes an insulating layer, which is formed on the second semiconductor layer and arranged corresponding to the second opening, and the transparent conductive layer covers the insulating layer. By designing that the insulating layer is arranged corresponding to the second opening, that is, the insulating layer is also arranged only under the end of the extended electrode away from the second electrode pad, on the one hand, the design of the insulating layer can be used to avoid direct injection of current, further ensuring the reliability of the light emitting diode, and on the other hand, the design can also be used to further promote the current at the end of the extended electrode to diffuse more effectively and evenly around, thereby improving the luminous efficiency of the light emitting diode chip; in addition, only a small amount of necessary insulating layers are provided, which can effectively avoid the increase of chip voltage caused by the excessive area of ​​the current blocking layer.

[0031] In one embodiment, the width of the insulating layer is greater than or equal to the width of the second opening, thereby enhancing the current diffusion to the surroundings at the end of the extended electrode, thereby further improving the overall current uniformity of the light emitting diode.

[0032] In one embodiment, the ratio of the area of ​​the insulating layer to the area of ​​the second opening is in the range of 10% to 200%. The insulating layer at the end of the extended electrode and the second opening with a large size are designed to further improve the reliability and luminous efficiency of the light-emitting diode chip, and also to avoid the voltage increase caused by the current blocking layer being too large.

[0033] In one embodiment, the transparent conductive layer forms a third opening at the pad portion of the second electrode to expose a portion of the upper surface of the second semiconductor layer at the second electrode pad portion, and a size of the third opening is smaller than a size of the second electrode pad portion.

[0034] In one embodiment, a size of the first opening is smaller than a size of the third opening, a pad portion of the second electrode contacts the second semiconductor layer, and an extended portion of the second electrode contacts the transparent conductive layer.

[0035] Through the above arrangement, the second electrode pad portion can be electrically connected to the second semiconductor layer through the first opening of the protective layer and the third opening of the transparent conductive layer, and the second electrode extension portion can be in contact with the transparent conductive layer through the second opening of the protective layer, thereby being electrically connected to the second semiconductor layer. At the same time, by setting the size of the first opening smaller than the size of the third opening, the brightness of the light-emitting diode is further improved.

[0036] In one embodiment, the first opening is a ring-shaped structure, and the inner circle diameter and the outer circle diameter of the ring-shaped structure are both smaller than the diameter of the third opening, so as to further improve the brightness of the light-emitting diode.

[0037] In one embodiment, the protective layer further includes at least one feeler extending from the first opening to the periphery of the second electrode pad portion, exposing a portion of the upper surface of the transparent conductive layer, and at the position of the feeler, the pad portion of the second electrode is in contact with the second semiconductor layer and the transparent conductive layer at the same time. Through the feeler, the second electrode pad portion can be in contact with the transparent conductive layer, which can increase the contact area between the second electrode pad portion and the transparent conductive layer, which is beneficial to the diffusion of current, thereby further alleviating the current congestion effect on the second electrode and reducing the risk of metal precipitation and electrode burning.

[0038] In one embodiment, the light-emitting diode also includes a first electrode, the first electrode includes a pad portion and an extension portion, the pad portion of the first electrode is located on the first semiconductor layer, the extension portion of the first electrode is located on the second semiconductor layer, and forms an ohmic contact with the first semiconductor layer through a series of through holes penetrating the second semiconductor layer and the light-emitting layer, and a protective layer is provided between the first electrode extension portion and the second semiconductor layer.

[0039] The present invention further provides a light emitting device, which uses the light emitting diode described in any of the above embodiments to effectively improve the performance of the light emitting device.

[0040] The technical solution of the present invention will be clearly and completely described below through a variety of specific implementations in conjunction with the accompanying drawings in the embodiments of the present invention. Example 1

[0041] See also Figure 1~Figure 4 , Figure 1 A schematic top view of a light emitting diode provided in Embodiment 1 of the present invention, Figure 2 For along Figure 1 Schematic diagram of the cross-sectional structure of the A-A' line, Figure 3 For Figure 2 A partial enlarged schematic diagram of the box area, Figure 4 For along Figure 1Schematic diagram of the cross-sectional structure of the BB' line. In order to achieve at least one of the above advantages or other advantages, an embodiment of the present invention provides a light-emitting diode, which may at least include a substrate 10, a semiconductor stack 12, a first electrode 21, a second electrode 22, a transparent conductive layer 16, and a protective layer 18. The first electrode 21 includes a pad portion 211 and an extension portion 212, the second electrode 22 includes a pad portion 221 and an extension portion 222, and the second electrode extension portion 222 includes a first end 2221 connected to the second electrode pad portion 221 and a second end 2222 away from the second electrode pad portion 221.

[0042] Specifically, the substrate 10 may be a transparent substrate, a non-transparent substrate, or a semi-transparent substrate. The substrate 10 may be selected from, but not limited to, sapphire, aluminum nitride, gallium nitride, silicon, silicon carbide, and glass. Its surface structure may be a planar structure or a patterned structure. In some embodiments, the substrate 10 may be a combined patterned substrate. In other embodiments, the substrate 10 may be thinned or removed to form a thin film chip.

[0043] The semiconductor stack 12 is disposed on the upper surface of the substrate 10, and the semiconductor stack 12 includes a first semiconductor layer 123, a light emitting layer 124, and a second semiconductor layer 125 stacked in sequence. The first semiconductor layer 123 is formed on the substrate 10, and as a layer grown on the substrate 10, it can be a gallium nitride semiconductor layer doped with n-type impurities, such as Si. In some embodiments, a buffer layer can be further disposed between the first semiconductor layer 123 and the substrate 10. In other embodiments, the first semiconductor layer 123 can also be connected to the substrate 10 through a bonding layer.

[0044] The light-emitting layer 124 is formed on the first semiconductor layer 123, and the light-emitting layer 124 may be a quantum well structure (QuantumWell, referred to as QW). In some embodiments, the light-emitting layer 124 may also be a multiple quantum well structure (Multiple QuantumWell, referred to as MQW), wherein the multiple quantum well structure includes multiple quantum well layers (Well) and multiple quantum barrier layers (Barrier) alternately arranged in a repeated manner. In addition, the composition and thickness of the well layer in the light-emitting layer 124 determine the wavelength of the generated light. In particular, by adjusting the composition of the well layer, a light-emitting layer that generates different colors of light such as ultraviolet light, blue light, green light, and yellow light can be provided.

[0045] The second semiconductor layer 125 is formed on the light emitting layer 124. The second semiconductor layer 125 may be a gallium nitride semiconductor layer doped with p-type impurities, such as Mg. Although the first semiconductor layer 123 and the second semiconductor layer 125 may be single-layer structures, the present invention is not limited thereto and may be multiple layers and may include a superlattice layer. In addition, in other embodiments, when the first semiconductor layer 123 is doped with p-type impurities, the second semiconductor layer 125 may be doped with n-type impurities, that is, the first semiconductor layer 123 is a P-type semiconductor layer and the second semiconductor layer 125 is an N-type semiconductor layer.

[0046] In an embodiment, the second semiconductor layer 125 includes a table for forming the first electrode 21 and a series of through holes 40 penetrating the second semiconductor layer 125 and the light emitting layer 124, thereby exposing a portion of the surface of the first semiconductor layer 123, and the number of the through holes 40 ranges from 1 to 15. The transparent conductive layer 16 is formed on the second semiconductor layer 125, and a third opening 33 is formed at a corresponding position of the pad portion 221 of the second electrode, exposing a portion of the upper surface of the second semiconductor layer 125 located in the second electrode pad region, and a sixth opening 36 is formed at a corresponding position of the extension portion 212 of the first electrode, the size of the sixth opening 36 is larger than the size of the through hole 40, and outside the through hole 40, a transparent conductive layer 16 and a protective layer 18 are sandwiched between the first electrode extension portion 212 and the second semiconductor layer 125; the protective layer 18 is formed on the transparent conductive layer 16, and at the same time covers the upper surface of the table and the side wall connecting the table and the upper surface of the second semiconductor layer 125, that is, basically covers the surface of the entire device, and a first opening 31 and a second opening 32 are formed at corresponding positions of the pad portion 221 and the extension portion 222 of the second electrode, exposing the portion located at A portion of the upper surface of the second semiconductor layer 125 in the second electrode pad area and a portion of the upper surface of the transparent conductive layer 16 located in the second electrode extension area are formed so that the second electrode pad portion 221 contacts the second semiconductor layer 125 through the first opening 31, and the second electrode extension portion 222 contacts the transparent conductive layer 16 through the second opening 32. The protective layer 18 forms a fourth opening 34 and a fifth opening 35 at corresponding positions of the pad portion 211 and the extension portion 212 of the first electrode. The fifth opening 35 is formed in the through hole 40. The size of the fifth opening 35 is smaller than the size of the through hole 40. In the through hole 40, the protective layer 18 covers the side wall of the through hole 40. The first electrode 21 and the second electrode 22 are formed on the protective layer 18, wherein the first electrode pad portion 211 is formed on the table and contacts the first semiconductor layer 123 through the fourth opening 34. Figure 1 , Figure 4As shown, the fourth opening 34 may be an annular opening, the first electrode extension portion 212 is formed on the protective layer 18 located above the second semiconductor layer 125, and contacts the first semiconductor layer 123 through the fifth opening 35 and the through hole 40, the second electrode pad portion 221 contacts the second semiconductor layer 125 through the first opening 31, and the second electrode extension portion 222 contacts the transparent conductive layer 16 through the second opening 32, as shown in FIG. Figures 1 to 3 As shown, the first opening 31 may be an annular opening.

[0047] The first electrode 21 and the second electrode 22 may be metal electrodes, that is, the first electrode 21 and the second electrode 22 are made of metal materials, for example, at least one of nickel, gold, chromium, titanium, platinum, palladium, rhodium, iridium, aluminum, tin, indium, tantalum, copper, cobalt, iron, ruthenium, zirconium, tungsten and molybdenum, or at least one of alloys or laminates selected from the above materials. As an example, in this embodiment, the first electrode 21 may be an N electrode, and the second electrode 22 may be a P electrode.

[0048] The transparent conductive layer 16 may include at least one of indium tin oxide (ITO), zinc-doped indium tin oxide (ZITO), zinc indium oxide (ZIO), gallium indium oxide (GIO), zinc tin oxide (ZTO), fluorine-doped tin oxide (FTO), aluminum-doped zinc oxide (AZO), and gallium-doped zinc oxide (GZO). As an example, in this embodiment, the transparent conductive layer 16 is preferably an ITO (indium tin oxide semiconductor transparent conductive film) layer formed by evaporation or sputtering process.

[0049] The material of the protective layer 18 may include a non-conductive material. The non-conductive material is preferably an inorganic material or a dielectric material. The inorganic material may include silica gel. The dielectric material includes an electrically insulating material such as aluminum oxide, silicon nitride, silicon oxide, titanium oxide, or magnesium fluoride. For example, the protective layer 18 may be silicon dioxide, silicon nitride, titanium oxide, tantalum oxide, niobium oxide, barium titanate, or a combination thereof, and the combination thereof may be, for example, a Bragg reflector (DBR) formed by repeatedly stacking two materials with different refractive indices. As an example, in this embodiment, the material of the protective layer 18 is SiO2. The protective layer 18 has different effects depending on the designed position. In the light-emitting diode structure described in this embodiment, the protective layer 18 protects the surface of the light-emitting diode on the one hand, and on the other hand, serves as a current blocking layer to suppress the current over-injection under the electrode and increase the current diffusion of the transparent conductive layer 16. Considering the requirements of both, its thickness d is preferably λ / 4n×(2k-1), where λ is the emission wavelength of the light-emitting layer 124, n is the refractive index of the protective layer 18, k is a natural number greater than 1, and the preferred value of k is 2-3, and the corresponding thickness is preferably 150nm-500nm. When the thickness of the protective layer 18 is too small, it is not conducive to playing the role of current blocking layer and protection. When the thickness is too large, the absorption of the material itself will increase the light loss.

[0050] Please see Figure 3 , Figure 3 for Figure 2 The partially enlarged schematic diagram of the frame area shows a partially enlarged view of the second electrode 22, the transparent conductive layer 16 forms a third opening 33 at a position corresponding to the second electrode pad portion 221, the protective layer 18 forms a first opening 31 at a position corresponding to the second electrode pad portion 221, the protective layer 18 covers the inner side wall of the third opening 33, the diameter of the first opening 31 is preferably smaller than the diameter of the third opening 33, thereby further improving the brightness of the light-emitting diode, specifically, the first opening 31 is a ring structure, the inner circle diameter of the first opening 31 is defined as d1', the outer circle diameter is d1, the diameter of the second electrode pad portion 221 is d2, and the diameter of the third opening 33 is d3, and the relationship between the four is preferably: d2>d3>d1>d1', thereby the upper surface of the second electrode pad portion 221 is stepped. It should be noted that in some other embodiments, the diameter of the first opening 31 is preferably also larger than the diameter of the third opening 33. In this design, the adhesion between the electrode and the epitaxial layer can be effectively increased, and the risk of the electrode and the attachment interface falling off during wire bonding can be reduced. Similarly, in the present embodiment, the outer diameter and the inner diameter of the first opening 31 are preferably smaller than the diameter of the third opening 33, thereby further improving the brightness of the light-emitting diode. In some other embodiments, the outer diameter of the first opening 31 may be larger than the diameter of the third opening 33, and the inner diameter may be smaller than the diameter of the third opening 33, which can also effectively increase the adhesion between the electrode and the epitaxial layer and improve the electrode bonding capability.

[0051] More preferably, the first opening 31 of the protective layer 18 located below the second electrode pad portion 221 may have at least one antenna 310 extending in a direction away from the pad portion 221, and the number of antennae 310 ranges from 1 to 20. At the position of the antennae 310, the second electrode pad portion 221 is in contact with the second semiconductor layer 125 and the transparent conductive layer 16 at the same time. Through the antennae 310, the second electrode pad portion 221 can be in contact with the transparent conductive layer 16, which can increase the contact area between the second electrode pad portion 221 and the transparent conductive layer 16, which is beneficial to the diffusion of current, thereby further alleviating the current congestion effect on the second electrode and reducing the risk of metal precipitation and electrode burning.

[0052] In the present embodiment, the protective layer 18 of the light-emitting diode protects the light-emitting diode from being damaged on the one hand, and can directly serve as a current blocking layer on the other hand, for suppressing the current over-injection under the electrode and increasing the current diffusion of the transparent conductive layer 16; the second electrode 22 directly contacts the semiconductor layer in the pad area, effectively increasing the adhesion between the electrode and the epitaxial layer, and reducing the risk of the electrode and the attachment interface falling off during wire bonding; the second electrode pad portion 221 adopts a design of multiple steps to effectively buffer the impact force of the wire bonding and reduce the impact and damage to the pad portion during the wire bonding process; the second electrode extension portion 222 is located on the protective layer 18, and contacts the transparent conductive layer 16 through the opening in the protective layer 18, so that the electrode extension portion forms a step shape with upper and lower rises, increases the angle of light emission at the electrode extension portion, and improves the light extraction efficiency. At the same time, since the electrode extension portion has a high step and a low step undulation distribution, the contact area between the electrode and other objects can be reduced, effectively reducing the damage to the electrode extension portion during the later film inversion, transportation and transfer, and reducing the dirt on the electrode extension portion.

[0053] In the present invention, the protective layer 18 forms a series of second openings 32 below the second electrode extension 222. The second openings 32 are arranged in sequence along the extension direction gradually away from the second electrode pad 221. The extension direction of the second electrode pad 221 is also the direction from the first end 2221 of the second electrode extension to the second end 2222 of the second electrode extension. There are intervals between the second openings 32. The second openings 32 and the intervals are alternately arranged along the extension direction of the second electrode pad 221. The number of the second openings 32 and the intervals is 1 to 25. In this embodiment, the intervals between the second openings 32 have the same size, and the second openings 32 include a plurality of first openings 321 and at least one second opening 322 of the same size. The second opening 322 is formed at the end 2220 of the second electrode extension away from the second electrode pad 221, that is, the second opening 322 is formed below the second end 2222 of the second electrode extension, wherein the size of the second opening 322 is greater than the size of the first opening 321. The present invention designs the second opening 32 of the second electrode extension part 222 of the protective layer 18 in a differentiated size, specifically, increasing the size of the second opening part 322 located at the end 2220 of the second electrode extension part away from the second electrode pad part 221. On the one hand, since the end of the extended electrode is often a high current density area, by setting the second opening part 322 with the largest size below the second end 2222 of the second electrode extension part, it is possible to avoid the occurrence of ESD explosion points at the end of the extended electrode due to excessive charge concentration, thereby improving the chip's anti-static impact capability and further ensuring the reliability of the light-emitting diode; on the other hand, it is possible to make the current at the end of the extended electrode diffuse as evenly as possible through the large-sized second opening part 322 to avoid direct injection of current at the end of the extended electrode, promote lateral expansion of the current, and at the same time improve the overall current uniformity of the light-emitting diode, thereby improving the reliability and luminous efficiency of the light-emitting diode chip. For details, please refer to Figure 6 , Figure 6 A schematic diagram of the current flow path of the light emitting diode provided by the present invention, wherein Figure 6 (a) is the four processes of known mesa etching (MESA), transparent conductive layer (such as ITO), protective layer and electrode mentioned in the background technology. It can be seen that the current is easily too concentrated at the second end 2222 of the second electrode extension part / the end 2220 of the second electrode extension part, thereby generating an ESD explosion point; Figure 6(b) is a schematic diagram of the current flow path of the light-emitting diode provided by the present invention. By increasing the size of the second opening 322 at the end 2220 of the second electrode extension portion far away from the second electrode pad portion 221, the current can be diffused as evenly as possible to the surroundings through the large-sized second opening 322 at the end of the extended electrode, thereby improving the reliability and luminous efficiency of the light-emitting diode chip. In addition, the protective layer 18 is first formed on the transparent conductive layer 16, and then the second electrode 22 is formed, which can reduce the probability of active metals in the electrode structure being oxidized during the production of the protective layer 18. It should be noted that in the present invention, there can be more than one second opening 322. For example, there are more than two second openings 322, and the size of any second opening 322 is larger than the size of any first opening 321. It can be selected and used according to specific actual needs, and the present application is not limited to this. For example, when the size of the second opening 322 is less than 10 times the size of the first opening 321, it is preferred that there is one second opening 322; when the size of the second opening 322 is more than 10 times the size of the first opening 321, it is preferred that there are more than two second openings 322.

[0054] In the present invention, the size of the second opening 322 is at least twice the size of the first opening 321; preferably, the size of the second opening 332 is 2 to 20 times the size of the first opening 321; more preferably, the size of the second opening 332 is 2 to 15 times the size of the first opening 321; further, the size of the second opening 332 is 4 to 12 times the size of the first opening 321, and optionally, the size of the second opening 322 is at least 5 times, 8 times, 10 times, 12 times, 14 times, etc. The size of the first opening 321 can be limited by the multiple of the size of the second opening 322 and the size of the first opening 321, so that the current can be more effectively diffused to the surroundings through the large-sized second opening 322, avoiding the ESD explosion point caused by the charge concentration phenomenon, and at the same time improving the overall current uniformity of the light-emitting diode, thereby improving the reliability and luminous efficiency of the light-emitting diode chip.

[0055] Please continue to see Figure 1The second opening 322 and the second electrode extension 222 have an overlapping portion, and the length of the overlapping portion accounts for 2% to 40% of the length of the second electrode extension 222, or the area of ​​the overlapping portion accounts for 2% to 40% of the area of ​​the second electrode extension 222. Preferably, the proportion is 5% to 25%, and more preferably, the proportion is 10% to 20%. Optionally, the length proportion of the overlapping portion or the area proportion of the overlapping portion can be, for example, 12%, 14%, 16%, 18%, etc. The length or area proportion of the overlapping portion between the second opening 322 and the second electrode extension 222 further promotes the current to be more effectively diffused to the surroundings through the large-sized second opening 322, thereby improving the overall current uniformity on the second electrode 22 and further improving the luminous efficiency of the light-emitting diode chip. It should be noted that, since the second electrode extension portion 222 does not include a simple straight portion, for example, in the present embodiment, the second electrode extension portion 222 includes a first curved portion 222-1, a straight portion 222-2, and a second curved portion 222-3, one end of the first curved portion 222-1 is connected to the second electrode pad portion 221 and the other end is connected to the straight portion 222-2, one end of the straight portion 222-2 is connected to the first curved portion 222-1 and the other end is connected to the second curved portion 222-3, one end of the second curved portion 222-3 is connected to the straight portion 222-2 and the other end is gradually bent in a direction away from the first electrode 21. More specifically, the first curved portion 222-1 includes an extension portion 222-1-0, one end of the extension portion 222-1-0 is connected to the electrode pad portion and the other end is connected to the straight portion 222-2, and the second curved portion 222-3 includes a circular end portion 222-3-0. The length and area of ​​the second electrode extension portion 222 mentioned above include the length and area of ​​the entire section from the extension portion 222-1-0 to the circular end portion 222-3-0.

[0056] The method for manufacturing a light emitting diode of the present invention mainly includes four processes: mesa etching (MESA), manufacturing a transparent conductive layer 16, manufacturing a protective layer 18, and manufacturing an electrode. Figure 5 The five processes and the corresponding mask patterns are shown and are briefly described below.

[0057] First, a semiconductor stack 12 is provided, which generally includes a substrate 10 , a first semiconductor layer 123 , a light emitting layer 124 , and a second semiconductor layer 125 .

[0058] Next, refer to Figure 5 The pattern shown in (a) defines a first electrode region and a second electrode region on the surface of the semiconductor stack 12, removes the empty area, and forms a terrace of the first electrode 21 and a series of through holes 40; Next, refer to Figure 5The pattern shown in (b) is as follows: a transparent conductive layer 16 is formed on the second semiconductor layer 125 of the semiconductor stack 12, the mesa region is etched away, and an opening 33 is formed in the pad region of the second electrode region, and an opening 36 is formed at a position corresponding to the through hole 40; Next, refer to Figure 5 The pattern shown in (c) is shown in FIG. 1 , a protective layer 18 is formed on the transparent conductive layer 16, and the protective layer 18 covers the side wall of the through hole 40, the side wall between the transparent conductive layer 16 and the table, and the table surface. An opening 31 is formed in the pad area of ​​the second electrode area, an opening 32 is formed in the extension area of ​​the second electrode area, an opening 34 is formed on the table, and an opening 35 is formed in the extension area of ​​the first electrode. The opening 35 is formed in the through hole 40, and the size of the opening 35 is smaller than the size of the through hole 40. Preferably, the opening 31 is an annular structure, and the inner circle diameter d1' and the outer circle diameter d1 of the annular structure are both smaller than the diameter d3 of the opening 33. Preferably, the opening 32 includes a plurality of first openings 321 of the same size and a second opening 322, and the second opening 322 is arranged below the second end 2222 of the second electrode extension, and the size of the second opening 322 is larger than the size of the first opening 321.

[0059] Next, refer to Figure 5 The pattern shown in (d) is shown in FIG. 1 , and the first electrode 21 and the second electrode 22 are made on the protective layer 18. The second electrode pad portion 221 contacts the second semiconductor layer 125 through the first opening 31, the pad portion 221 of the second electrode contacts the second semiconductor layer 125 and the protective layer 18, and the second electrode extension portion 222 contacts the transparent conductive layer 16 through the second opening 32; the pad portion 211 of the first electrode is located on the first semiconductor layer 123, the first electrode pad portion 211 contacts the first semiconductor layer 123 through the fourth opening 34, the pad portion 221 of the first electrode contacts the first semiconductor layer 123 and the protective layer 18, the extension portion 212 of the first electrode is located on the second semiconductor layer 125, and the first electrode extension portion 212 contacts the first semiconductor layer 123 through the fifth opening 35 and the through hole 40.

[0060] It should be noted that the shape and size of the openings 31 and 34 are not limited to the above description, and they can also directly form a non-annular structure. For example, in some implementations, there is no protective layer 18 below the center of the pad portion of the electrode, and it directly contacts the semiconductor stack 12. In other embodiments, the openings 31 and 34 can also be designed as a series of antenna structures distributed around the pad area, exposing the transparent conductive layer 16, and the pad area does not form an opening structure. In this case, the pad portion of the electrode is completely formed on the protective layer 18 and can be connected to the antenna structure through a metal lead. Example 2

[0061] See also Figure 7 , Figure 8 , Figure 7 A schematic top view of a light emitting diode provided in the second embodiment of the present invention, Figure 8 For along Figure 7 Schematic diagram of the cross-sectional structure of the A-A' line. Compared with the light-emitting diode of the first embodiment of the present invention, the light-emitting diode of the second embodiment is mainly different in that: in this embodiment, the size of the second openings 32 of the protective layer 18 increases successively along the extension direction gradually away from the second electrode pad portion 221. Specifically, at a position close to the second electrode pad portion 221, the size of the second opening 32 is the smallest, and as it moves away from the second electrode pad portion 221, the size of the opening 32 becomes larger and larger, wherein the second opening 32 farthest from the second electrode pad portion 221, that is, at the second end 2222 of the second electrode extension portion, has the largest size. Since the current density tends to gradually increase along the extension direction gradually away from the second electrode pad portion 221, in some preferred embodiments, the design of the second opening 32 increasing in size along the extension direction of the electrode extension portion can prevent the occurrence of ESD explosion points in areas with high current density, such as near the end of the extension electrode, due to excessive charge concentration; at the same time, it can also alleviate the current congestion effect on the second electrode, improve the overall current uniformity of the light-emitting diode, and thus improve the reliability and luminous efficiency of the light-emitting diode chip. Example 3

[0062] See also Fig. 9 , Fig.10 , Fig. 9 A schematic top view of a light emitting diode provided in Embodiment 3 of the present invention is shown in FIG. Fig.10 For along Fig. 9 Schematic diagram of the cross-sectional structure of the A-A' line. Compared with the light-emitting diode of the first embodiment of the present invention, the light-emitting diode of the third embodiment is mainly different in that: the protective layer 18 has a plurality of second openings 32, and there are intervals between the second openings 32, and the size of the intervals decreases gradually along the extension direction gradually away from the second electrode pad portion 221. Specifically, at a position close to the second electrode pad portion 221, the interval size of the second openings 32 is the largest, and as it moves away from the second electrode pad portion 221, the size of the intervals becomes smaller and smaller, wherein the second openings 32 farthest from the second electrode pad portion 221, that is, located at the second end 2222 of the second electrode extension portion, have the smallest interval size. By designing that the intervals between the second openings 32 decrease in the extension direction of the second electrode extension portion 222, it is also possible to prevent ESD explosion points from occurring in areas with high current density due to excessive charge concentration; at the same time, it is also possible to improve the overall current uniformity of the light-emitting diode, thereby improving the reliability and luminous efficiency of the light-emitting diode chip.

[0063] Furthermore, in some variant implementations, there is a first interval between the first openings 321, and there is a second interval between the first openings 321 and the second openings 322. The first intervals are the same in size, and the second intervals can be larger than the first intervals. This further promotes the current to diffuse more effectively and evenly around the end of the extended electrode through the large-sized second openings 322. In some variant implementations, the size of the first interval decreases in sequence along the extension direction gradually away from the second electrode pad portion 221, and the size of the second interval can be larger than the size of part or all of the first interval. Example 4

[0064] See also Figure 11~Figure 18 , Fig.11 A schematic top view of a light emitting diode provided in the fourth embodiment of the present invention, Fig.13 , Fig.15 , Fig.17 Schematic top view of several other light emitting diodes provided in the fourth embodiment of the present invention, Fig.12 , Fig.14 , Fig.16 , Fig.18 Along Fig.11 , Fig.13 , Fig.15 , Fig.17Schematic diagram of the cross-sectional structure of the A-A' line. Compared with the light-emitting diode of the first embodiment of the present invention, the light-emitting diode of the fourth embodiment is mainly different in that: the light-emitting diode also includes an insulating layer 14, the insulating layer 14 is formed on the second semiconductor layer 125, and is sandwiched between the second semiconductor layer 125 and the transparent conductive layer 16, the transparent conductive layer 16 covers the insulating layer 14, and the insulating layer 14 is only formed below the second end 2222 of the second electrode extension, and is arranged corresponding to the second opening 322, wherein the second end 2222 of the second electrode extension is located at an end away from the second electrode pad 221. In a more preferred embodiment, the insulating layer 14 is only arranged below the end 2220 of the second electrode extension. Specifically, the transparent conductive layer 16, the insulating layer 14, and the second semiconductor layer 125 are sequentially provided below the second end 2222 of the second electrode extension, and part of the protective layer 18, the transparent conductive layer 16, and the second semiconductor layer 125 are sequentially provided below other areas of the second electrode extension 222. The upper surface of the second electrode extension 222 thus formed is stepped. The light-emitting diode described in this embodiment is designed to correspond to the insulating layer 14 and the second opening 322, that is, the insulating layer 14 is formed as a current blocking layer only below the second end 2222 of the second electrode extension away from the second electrode pad 221. On the one hand, the design of the insulating layer 14 can be used to avoid direct injection of current, further ensuring the reliability of the light-emitting diode. On the other hand, the design can also be used to further promote the current to diffuse more effectively and evenly around the end of the extended electrode, thereby improving the luminous efficiency of the light-emitting diode chip. In addition, only a small amount of necessary insulating layers can be set to avoid the increase of chip voltage caused by the excessive area of ​​the current blocking layer. Furthermore, the four-layer structure of the insulating layer 14, the transparent conductive layer 16, the protective layer 18, and the second electrode extension 222 can form a full-angle reflector, thereby improving the reflection ability of the electrode extension area and reducing the light absorption efficiency. Among them, the insulating layer 14 is an insulating material, which can be an oxide, and can be a relatively transparent material, such as one or more combinations of silicon oxide, titanium oxide, silicon nitride, aluminum oxide, magnesium fluoride, spin-on glass (SOG), polymer (Polymer) and other materials. The present application is not limited to the examples listed here. The materials of the insulating layer 14 and the protective layer 18 are preferably both low-refractive index insulating materials, preferably with a refractive index of less than 1.5, and the materials can be the same or different. As an example, in this embodiment, the material of the insulating layer 14 is SiO2. Preferably, the thickness of the insulating layer 14 is between 50 and 500 nm.

[0065] In the present invention, the width of the insulating layer 14 is preferably greater than or equal to the width of the second opening portion 322, so as to enhance the diffusion of current to the surroundings at the end of the extended electrode, and further improve the overall current uniformity of the light-emitting diode. It should be noted that in other embodiments, the area of ​​the insulating layer 14 may also be smaller than the area of ​​the second opening portion 322, and can be selected and used accordingly according to specific actual needs, and the present application is not limited to this. The ratio of the area of ​​the insulating layer 14 to the area of ​​the second opening portion 322 ranges from 10% to 200%. Preferably, the ratio is 40% to 150%, and more preferably, the ratio is 50% to 120%, for example, it can be 50%, 70%, 90%, 110%, etc. Please continue to refer to Fig.11 , Fig.12 In this embodiment, the width of the insulating layer 14 is greater than the width of the second opening 322, and the area of ​​the insulating layer 14 is greater than the area of ​​the second opening 322. In some modified embodiments, please refer to Fig.13 , Fig.14 In this embodiment, the width of the insulating layer 14 is greater than the width of the second opening 322, and the area of ​​the insulating layer 14 is smaller than the area of ​​the second opening 322. Fig.15 , Fig.16 In this embodiment, the width of the insulating layer 14 is equal to the width of the second opening 322, and the area of ​​the insulating layer 14 is equal to the area of ​​the second opening 322. The insulating layer 14 at the end of the extended electrode is matched with the second opening 322 of large size to further improve the reliability and luminous efficiency of the light-emitting diode chip, and also avoid the voltage increase caused by the current blocking layer being too large.

[0066] In some embodiments, see Fig.17 , Fig.18The insulating layer 14 is distributed in blocks and is composed of a series of discrete block structures. There are gaps between the block structures, so that the current can not only diffuse to the surroundings at the end of the extended electrode, but also diffuse through the gaps between the blocks, so that the current diffuses more evenly at the end of the extended electrode, further improving the overall current uniformity of the light-emitting diode. The areas of several block structures can be equal. In some preferred embodiments, the areas of several block structures can also be unequal (not shown in the figure). Specifically, when the insulating layer 14 is composed of a series of block structures with unequal areas, the area of ​​the block structure is the largest at the position close to the second end 2222 of the second electrode extension part, and the area becomes smaller and smaller as it moves away from the second end 2222 of the second electrode extension part, and the area of ​​the block structure farthest from the second end 2222 of the second electrode extension part is the smallest. In this way, ESD explosion points can be prevented from occurring in areas with high current density, such as at the position close to the end of the extended electrode, due to excessive charge concentration; at the same time, the current congestion effect on the second electrode can be alleviated, the overall current uniformity of the light-emitting diode can be improved, and the reliability and luminous efficiency of the light-emitting diode chip can be improved.

[0067] The present invention further provides a light emitting device, which uses the light emitting diode described in any of the above embodiments to effectively improve the performance of the light emitting device.

[0068] In summary, the light-emitting diode provided by the present invention improves the reliability of the chip by designing the second opening of the second electrode extension portion with differentiated size by positioning the protective layer therein, specifically by increasing the size of the second opening portion at the end of the second electrode extension portion away from the second electrode pad portion.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A light emitting diode, characterized in that: The light emitting diode comprises: The semiconductor stack comprises, from bottom to top, a first semiconductor layer, a light-emitting layer, and a second semiconductor layer stacked in sequence; A transparent conductive layer formed on the second semiconductor layer; A protective layer formed on the transparent conductive layer; A second electrode is formed on the protective layer and includes a pad portion and an extension portion; The protective layer forms a first opening and a second opening at the pad portion and the extension portion of the second electrode, respectively, to expose a portion of the upper surface of the second semiconductor layer located at the pad portion of the second electrode and a portion of the upper surface of the transparent conductive layer located at the extension portion of the second electrode, and the second electrode is electrically connected to the second semiconductor layer through the first opening and the second opening; It is characterized in that the second opening of the protective layer includes a plurality of first opening portions and at least one second opening portion, the second opening portion is formed at the end away from the second electrode pad portion, and the size of the second opening portion is larger than the size of the first opening portion.

2. The light emitting diode according to claim 1, characterized in that: The second electrode extension portion has a first end connected to the second electrode pad portion and a second end away from the second electrode pad portion, and the second opening portion is formed below the second end of the second electrode extension portion.

3. The light emitting diode according to claim 1, characterized in that: The sizes of the plurality of first openings are the same.

4. The light emitting diode according to claim 1, characterized in that: The sizes of the plurality of first openings increase sequentially along an extending direction gradually away from the second electrode pad.

5. The light emitting diode according to claim 1, characterized in that: The size of the second opening is at least twice the size of the first opening.

6. The light emitting diode according to claim 1, characterized in that: The size of the second opening is 2 to 20 times the size of the first opening.

7. The light emitting diode according to claim 1, characterized in that: There are intervals between the second openings, and the intervals have the same size.

8. The light emitting diode according to claim 1, characterized in that: There are intervals between the second openings, and sizes of the intervals decrease in sequence along an extending direction gradually away from the second electrode pad portion.

9. The light emitting diode according to claim 1, characterized in that: The second opening portion and the second electrode extension portion have an overlapping portion, and a length of the overlapping portion is 2% to 40% of a length of the second electrode extension portion.

10. The light emitting diode according to claim 1, characterized in that: The second opening portion and the second electrode extension portion have an overlapping portion, and an area of ​​the overlapping portion is 2% to 40% of an area of ​​the second electrode extension portion.

11. The light emitting diode according to claim 1, characterized in that: The light emitting diode further includes an insulating layer, which is formed on the second semiconductor layer and arranged corresponding to the second opening, and the transparent conductive layer covers the insulating layer.

12. The light emitting diode according to claim 11, characterized in that: The width of the insulating layer is greater than or equal to the width of the second opening.

13. The light emitting diode according to claim 11, characterized in that: The ratio of the area of ​​the insulating layer to the area of ​​the second opening is in a range of 10% to 200%.

14. The light emitting diode according to claim 1, characterized in that: The transparent conductive layer forms a third opening at the pad portion of the second electrode to expose a portion of the upper surface of the second semiconductor layer located at the second electrode pad portion, and a size of the third opening is smaller than a size of the second electrode pad portion.

15. The light emitting diode according to claim 14, characterized in that: The size of the first opening is smaller than that of the third opening, the pad portion of the second electrode contacts the second semiconductor layer, and the extension portion of the second electrode contacts the transparent conductive layer.

16. The light emitting diode according to claim 14, characterized in that: The first opening is an annular structure, and the inner circle diameter and the outer circle diameter of the annular structure are both smaller than the diameter of the third opening.

17. The light emitting diode according to claim 14, characterized in that: The protective layer also includes at least one antenna extending from the first opening to the periphery of the second electrode pad portion, exposing a portion of the upper surface of the transparent conductive layer. At the position of the antenna, the pad portion of the second electrode is in contact with the second semiconductor layer and the transparent conductive layer at the same time.

18. The light emitting diode according to claim 1, characterized in that: The light-emitting diode also includes a first electrode, which includes a pad portion and an extension portion. The pad portion of the first electrode is located on the first semiconductor layer, and the extension portion of the first electrode is located on the second semiconductor layer. The extension portion of the first electrode forms an ohmic contact with the first semiconductor layer through a series of through holes that penetrate the second semiconductor layer and the light-emitting layer. The protective layer is provided between the extension portion of the first electrode and the second semiconductor layer.

19. A light emitting device, characterized in that: A light emitting diode as claimed in any one of claims 1 to 18 is used.

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