Light emitting diode and light emitting device

Abstract

The application relates to the technical field of semiconductors, and provides a light-emitting diode and a light-emitting device. The light-emitting diode comprises an epitaxial structure, a second contact electrode and an insulating layer. The epitaxial structure comprises a first semiconductor layer, an active layer and a second semiconductor layer which are sequentially stacked; a plurality of second contact electrodes are distributed above the second semiconductor layer and are electrically connected to the second semiconductor layer; the insulating layer covers at least part of the second contact electrodes and the epitaxial structure; the insulating layer comprises a second through hole which exposes part of the surface of the second contact electrode; the second through hole and the edge of the second contact electrode have a minimum distance, and the minimum distance is a first interval; and the first intervals of at least two second contact electrodes and the second through hole are not equal. Through the design, the EOS capability of the light-emitting diode can be effectively improved, and the risk that the light-emitting diode is easily structurally burned under an overvoltage condition and thus loses the capability can be avoided.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to a light-emitting diode and a light-emitting device. Background Technology

[0002] A light-emitting diode (LED) is a semiconductor light-emitting element, typically made of semiconductors such as GaN, GaAs, GaP, and GaAsP. Its core is a PN junction that emits light. LEDs have advantages such as high luminous intensity, high efficiency, small size, and long lifespan, and are considered one of the most promising light sources currently available. However, existing LEDs still suffer from poor EOS (Electrical Over-Stress) capability due to improper design. Summary of the Invention

[0003] To address the shortcomings of existing light-emitting diodes, the present invention provides a light-emitting diode comprising an epitaxial structure, a plurality of second contact electrodes, and an insulating layer.

[0004] The epitaxial structure includes a first semiconductor layer, an active layer, and a second semiconductor layer stacked sequentially; a plurality of second contact electrodes are distributed above the second semiconductor layer and electrically connected to the second semiconductor layer; an insulating layer at least covers a portion of the second contact electrodes and the epitaxial structure; the insulating layer includes a second via exposed on the surface of a portion of the second contact electrode; the second via has a minimum distance from the edge of the second contact electrode, the minimum distance being a first spacing; at least two of the second contact electrodes have unequal first spacings from the second via.

[0005] The present invention also provides a light-emitting device, which employs a light-emitting diode as described in the above embodiments.

[0006] Based on the above, compared with the prior art, the light-emitting diode provided by the present invention, by limiting the spacing between the second contact electrode and the second through hole, can effectively improve the EOS capability of the light-emitting diode and avoid the risk of structural burn-out and failure of the light-emitting diode under overvoltage conditions.

[0007] Other features and beneficial effects of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other beneficial effects of the invention can be realized and obtained by means of the structures particularly pointed out in the description, claims and drawings. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Unless otherwise specified, the positional relationships shown in the drawings in the following description are based on the direction in which the components are drawn in the figure.

[0009] Figure 1 A cross-sectional view of a light-emitting diode provided according to an embodiment of the present invention;

[0010] Figure 2 A top view of a light-emitting diode provided according to an embodiment of the present invention;

[0011] Figure 3 A top view of a light-emitting diode provided for another embodiment of the present invention;

[0012] Figure 4 for Figure 3 A magnified view of part A in the image;

[0013] Figure 5 A top view of a light-emitting diode provided for other embodiments of the present invention;

[0014] Figure 6 A cross-sectional view of a light-emitting diode provided in another embodiment of the present invention;

[0015] Figure 7 A cross-sectional view of a light-emitting diode provided for other embodiments of the present invention.

[0016] Figure label:

[0017] 10 – Epitaxial structure; 11 – First semiconductor layer; 12 – Active layer; 13 – Second semiconductor layer; 21 – Second contact electrode; 22 – First contact electrode; 31 – Second connecting electrode; 32 – First connecting electrode; 40 – Substrate; 50 – Insulating layer; 51 – Second via; 52 – First via; 61 – Current blocking layer; 62 – Current spreading layer; d1 – First sub-pitch; d2 – Second sub-pitch; d3 – Third sub-pitch; d4 – Fourth sub-pitch; W1 – First diameter; W2 – Second diameter; d5 – Third pitch; W3 – Third diameter; W4 – Fourth diameter. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. The technical features designed in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0019] In the description of this invention, it should be noted that all terms used in this invention (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains, and should not be construed as limiting the invention; it should be further understood that the terms used in this invention should be understood to have the same meaning as those in the context of this specification and in the relevant field, and should not be understood in an idealized or overly formal sense, except as expressly defined in this invention.

[0020] To achieve at least one or more advantages of the present invention, one embodiment of the present invention provides a light-emitting diode, the light-emitting diode comprising at least an epitaxial structure, a second contact electrode, and an insulating layer.

[0021] The epitaxial structure includes a first semiconductor layer, an active layer, and a second semiconductor layer stacked sequentially; multiple second contact electrodes are distributed above the second semiconductor layer and electrically connected to the second semiconductor layer; an insulating layer at least covers a portion of the second contact electrodes and the epitaxial structure; the insulating layer includes a second via exposed on the surface of the second contact electrode portion; there is a minimum distance between the second via and the edge of the second contact electrode, the minimum distance being a first spacing; at least two second contact electrodes have unequal first spacings from the second via. These limitations effectively improve the EOS (Effective Occurrence Limit) capability of the light-emitting diode.

[0022] In one embodiment, the first spacing is between 2 and 10 micrometers to improve the reliability of the light-emitting diode.

[0023] In one embodiment, the first spacing is defined as the distance between the bottom edge of the second through hole and the upper surface edge of the second contact electrode.

[0024] In one embodiment, the first spacing includes a first sub-spacing and a second sub-spacing, the first sub-spacing being greater than the second sub-spacing; the second contact electrode having the second sub-spacing is closer to the edge of the light-emitting diode than the second contact electrode having the first sub-spacing.

[0025] In one embodiment, the first spacing includes a first sub-spacing and a second sub-spacing, the first sub-spacing being greater than the second sub-spacing; the light-emitting diode further includes a plurality of first contact electrodes, the plurality of first contact electrodes being spaced apart and electrically connected to the first semiconductor layer above the first semiconductor layer; second contact electrodes are distributed between the plurality of first contact electrodes and around the plurality of first contact electrodes; at least one second contact electrode located between adjacent first contact electrodes has a first sub-spacing; at least one second contact electrode located around the plurality of first contact electrodes and closest to the edge of the light-emitting diode has a second sub-spacing.

[0026] In one embodiment, the difference between the first sub-pitch and the second sub-pitch is between 1 and 5 micrometers to further ensure photoelectric properties.

[0027] In one embodiment, the number of second contact electrodes having a second sub-pitch is less than the number of second contact electrodes having a first sub-pitch.

[0028] In one embodiment, the cross-sectional areas of the second through holes corresponding to each second contact electrode are equal on the same horizontal plane, and at least two second contact electrodes have unequal cross-sectional areas on the same horizontal plane.

[0029] In one embodiment, on the same horizontal plane, the second contact electrode with a smaller cross-sectional area is closer to the edge of the light-emitting diode than the second contact electrode with a larger cross-sectional area.

[0030] In one embodiment, the second contact electrode has a diameter, and at least two of the second contact electrodes have unequal diameters.

[0031] In one embodiment, the diameter of the second contact electrode includes a first diameter and a second diameter, the first diameter being larger than the second diameter, and the second contact electrode having the second diameter being closer to the edge of the light-emitting diode than the second contact electrode having the first diameter; the first diameter is between 18 and 30 micrometers, and the second diameter is between 15 and 25 micrometers.

[0032] By limiting the dimensions of the first spacing and the second contact electrode in the above embodiments, the balance between current distribution and luminous brightness in the light-emitting diode can be effectively controlled, thereby improving the EOS capability of the light-emitting diode.

[0033] In one embodiment, the light-emitting diode further includes a plurality of current blocking layers located below the second contact electrode; the orthographic projection of the second contact electrode on the epitaxial structure is located within the orthographic projection range of the current blocking layer on the epitaxial structure; the minimum distance between the second via located above the second contact electrode and the edge of the current blocking layer located below the second contact electrode is defined as the second spacing; at least two second contact electrodes have unequal second spacings.

[0034] In one embodiment, the second spacing is between 5 and 15 micrometers.

[0035] In one embodiment, the second spacing is defined as the distance between the bottom edge of the second via located above the second contact electrode and the upper surface edge of the current blocking layer located below the second contact electrode.

[0036] In one embodiment, the second spacing includes a third sub-spacing and a fourth sub-spacing, the third sub-spacing being greater than the fourth sub-spacing; the second contact electrode having the fourth sub-spacing is closer to the edge of the light-emitting diode than the second contact electrode having the third sub-spacing.

[0037] In one embodiment, the second spacing includes a third sub-spacing and a fourth sub-spacing, the third sub-spacing being greater than the fourth sub-spacing; the light-emitting diode further includes a plurality of first contact electrodes, the plurality of first contact electrodes being spaced apart and electrically connected to the first semiconductor layer above the first semiconductor layer; second contact electrodes are distributed between the plurality of first contact electrodes and around the plurality of first contact electrodes; at least one second contact electrode located between adjacent first contact electrodes has a third sub-spacing; at least one second contact electrode located around the plurality of first contact electrodes and closest to the edge of the light-emitting diode has a fourth sub-spacing.

[0038] In one embodiment, the difference between the third sub-pitch and the fourth sub-pitch is between 1 and 5 micrometers.

[0039] By limiting the second spacing in the above embodiments, the current distribution and brightness uniformity of the light-emitting diode can be further optimized, and the ESD capability of the light-emitting diode can be improved.

[0040] In one embodiment, the light-emitting diode further includes a plurality of first contact electrodes, which are staggered and distributed above the first semiconductor layer and electrically connected to the first semiconductor layer; a plurality of second contact electrodes are uniformly distributed around each first contact electrode.

[0041] In one embodiment, the insulating layer further includes a first through hole exposing the surface of the first contact electrode portion, and the minimum distance between the first contact electrode and the first through hole is defined as a third spacing, which is smaller than the first spacing, so as to effectively reduce light loss caused by electrode coverage and improve the brightness of the light-emitting diode.

[0042] In one embodiment, the light-emitting diode further includes a current spreading layer, a first connecting electrode, and a second connecting electrode. The current spreading layer is located between a second contact electrode and a second semiconductor layer. The first connecting electrode is located on an insulating layer and is electrically connected to a plurality of first contact electrodes. The second connecting electrode is located on an insulating layer and is electrically connected to a plurality of second contact electrodes.

[0043] The present invention also provides a light-emitting diode (LED), which includes an epitaxial structure, a second contact electrode, and an insulating layer. The epitaxial structure includes a first semiconductor layer, an active layer, and a second semiconductor layer stacked sequentially; a plurality of second contact electrodes are distributed above the second semiconductor layer and electrically connected to the second semiconductor layer; the insulating layer at least covers a portion of the second contact electrodes and the epitaxial structure; the insulating layer includes a second via exposed on the surface of the second contact electrode portion; the second via has a minimum distance from the edge of the second contact electrode, the minimum distance being a first spacing; the first spacing between the second contact electrode and the second via is equal; at least two of the second vias have unequal minimum diameters.

[0044] In one embodiment, the diameter of the second through hole includes a third diameter and a fourth diameter, wherein the third diameter is larger than the fourth diameter; the second through hole with the fourth diameter is closer to the edge of the light-emitting diode than the second through hole with the third diameter.

[0045] By limiting the size of the second through hole as described above, the photoelectric characteristics of the light-emitting diode can also be effectively improved.

[0046] The present invention also provides a light-emitting device that employs a light-emitting diode as described in any of the above embodiments to improve the performance of the light-emitting device.

[0047] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention and through various specific implementation methods.

[0048] Example 1

[0049] Please see Figures 1-5 , Figure 1 This is a cross-sectional view of a light-emitting diode provided in one embodiment of the present invention. The light-emitting diode provided in this embodiment includes at least an epitaxial structure 10, a second contact electrode 21, and an insulating layer 50.

[0050] The epitaxial structure 10 is disposed on the substrate 40. The substrate 40 may be an insulating substrate, preferably made of a transparent or translucent material. For example, the substrate 40 may be a sapphire substrate or a patterned sapphire substrate. The substrate 40 may also be made of a conductive or semiconductor material. For example, the material of the substrate 40 may include at least one of silicon carbide, silicon, magnesium aluminum oxide, magnesium oxide, lithium aluminum oxide, aluminum gallium oxide, and gallium nitride.

[0051] The epitaxial structure 10 includes a first semiconductor layer 11, an active layer 12, and a second semiconductor layer 13 sequentially stacked on a substrate 40. The first semiconductor layer 11 may be an N-type semiconductor layer, which can provide electrons to the active layer 12 under power. In some embodiments, the first semiconductor layer 11 includes an N-type doped nitride layer. The N-type doped nitride layer may include one or more N-type impurities of group IV elements. The N-type impurities may include one or a combination of Si, Ge, and Sn.

[0052] The active layer 12 can be a quantum well (QW) structure. In some embodiments, the active layer 12 can also be a multiple quantum well (MQW) structure, wherein the multiple quantum well structure includes multiple quantum well layers (Well) and multiple quantum barrier layers arranged alternately in a repeating manner, such as a GaN / AlGaN, InAlGaN / InAlGaN, or InGaN / AlGaN multi-quantum well structure. Furthermore, the composition and thickness of the well layers within the active layer 12 determine the wavelength of the generated light. To improve the luminescence efficiency of the active layer 12, this can be achieved by changing the depth of the quantum wells, the number of paired quantum wells and quantum barriers, the thickness, and / or other characteristics within the active layer 12.

[0053] The second semiconductor layer 13 can be a P-type semiconductor layer, which can provide holes to the active layer 12 under power. In some embodiments, the second semiconductor layer 13 includes a P-type doped nitride layer. The P-type doped nitride layer may include one or more P-type impurities of group II elements. The P-type impurities may include one or a combination of Mg, Zn, and Be. The second semiconductor layer 13 can be a single-layer structure or a multilayer structure with different compositions. Furthermore, the arrangement of the epitaxial structure 10 is not limited to this, and other functional or type epitaxial structures can be selected according to actual needs.

[0054] Please see Figure 1 and Figure 2 The second contact electrode 21 is located on the epitaxial structure 10 and electrically connected to the second semiconductor layer 13. The second contact electrode 21 has a block structure, which can be a regular shape such as a cylinder, elliptical cylinder, or prism, or other irregular shapes; no limitation is made here. By distributing the block structure across the surface of the epitaxial structure 10, the current spreading capability can be optimized, thus improving the EOS (Electrical Optimization) capability.

[0055] Preferably, the light-emitting diode further includes a first contact electrode 22, which is located on the epitaxial structure 10 and electrically connected to the first semiconductor layer 11. The first contact electrode 22 can be a block structure or a finger-like structure; the specific design can be tailored to the actual requirements of the flip-chip light-emitting diode and is not limited here. Figure 2 As shown, in this embodiment, the first contact electrode 22 is preferably also a block structure to avoid the finger structure covering the absorption of brightness.

[0056] Preferably, please continue reading. Figure 2 Multiple first contact electrodes 22 are staggered and spaced on the upper surface of the first semiconductor layer 11. Multiple second contact electrodes 21 are uniformly distributed around each first contact electrode 22. Specifically, the multiple first contact electrodes 22 are staggered rather than matrix-like. That is, compared to a matrix distribution where electrodes are arranged in a regular pattern to form neat rows and columns, the staggered distribution means that the first contact electrodes 22 are offset between adjacent rows or columns. This staggered distribution of the first contact electrodes 22 allows for more space between each first contact electrode 22 to accommodate more second contact electrodes 21 on the limited surface area of ​​the LED. On one hand, the increased number of second contact electrodes 21 ensures more uniform electrical and thermal conductivity across the LED, thereby improving the EOS (Electrical Emission) capability of the LED. On the other hand, the staggered distribution also enhances the electric field distribution at the edge of the LED, thereby increasing the LED brightness.

[0057] The first contact electrode 22 and the second contact electrode 21 can be metal electrodes, such as one or any combination of nickel, gold, titanium, platinum, palladium, chromium, aluminum, tin, indium, copper, iron, tungsten, and molybdenum. Preferably, both the first contact electrode 22 and the second contact electrode 21 include a substrate (e.g., Cr), a reflective layer on the substrate (e.g., Al), and a capping layer on the reflective layer (e.g., Ti, Pt, or Ni). The substrate ensures ohmic contact between the contact electrode and the epitaxial structure 10, and the thickness of the substrate is less than 10 nm, thereby avoiding any impact on reflectivity.

[0058] Furthermore, the insulating layer 50 also includes a first through-hole 52 exposing a portion of the surface of the first contact electrode 22. The minimum distance between the first contact electrode 22 and the first through-hole 52 is defined as a third spacing, wherein the third spacing is smaller than the first spacing. Specifically, as follows... Figure 1 As shown, there is a minimum distance between the first contact electrode 22 and the corresponding first through hole 52 above the first contact electrode 22. When the first through hole 52 is frustum-shaped, the third spacing is the distance from the bottom edge of the first through hole 52 to the edge of the upper surface of the first contact electrode 22. By designing the third spacing to be smaller than the first spacing, the light loss caused by electrode coverage is reduced, effectively improving the brightness of the light-emitting diode.

[0059] In some embodiments, a current spreading layer 62 may be disposed between the second contact electrode 21 and the epitaxial structure 10 to further improve conductivity and enhance the photoelectric characteristics of the light-emitting diode. A current blocking layer 61 may also be disposed below the second contact electrode 21 to suppress current accumulation near the second contact electrode 21 and improve current spreading performance. Alternatively, a current spreading layer 62 (not shown in the figure) and a current blocking layer 61 (not shown in the figure) may also be disposed between the first contact electrode 22 and the epitaxial structure 10 to improve the current spreading performance of the light-emitting diode. The specific design should be based on actual needs and is not limited here.

[0060] As an example, the current spreading layer 62 can be at least one of indium tin oxide (ITO) and zinc indium oxide (ZIO), and in this embodiment, the ITO layer is preferably formed by vapor deposition or sputtering process; the current blocking layer 61 can be SiO2, Si3N4, Al2O3, TiO2 or a composite structure thereof.

[0061] The insulating layer 5050 covers at least a portion of the second contact electrode 21 and the epitaxial structure 10, and may extend to cover a portion of the sidewalls of the epitaxial structure 10. The insulating layer 50 has different functions depending on its location. For example, when the insulating layer 50 covers the sidewalls of the epitaxial structure 10, it can be used to prevent electrical connection between the first semiconductor layer 11 and the second semiconductor layer 13 due to leakage of conductive material, reducing the possibility of short-circuit abnormalities in the light-emitting diode, but this disclosure is not limited to this. The material of the insulating layer 50 includes a non-conductive material. The non-conductive material is preferably an inorganic material or a dielectric material. The inorganic material may include silicone. The dielectric material includes electrically insulating materials such as aluminum oxide, silicon nitride, silicon oxide, titanium oxide, or magnesium fluoride. For example, the insulating layer 50 may be silicon dioxide, silicon nitride, titanium oxide, tantalum oxide, niobium oxide, barium titanate, or a combination thereof, such as a Bragg mirror (DBR) formed by repeatedly stacking two materials with different refractive indices.

[0062] The insulating layer 50 includes a second through hole 51 exposing a portion of the surface of the second contact electrode 21, facilitating the extraction of the second contact electrode 21 through the second through hole 51. The second through hole 51 can be a cylindrical hole with a vertical plane sidewall, or a frustum-shaped hole with an inclined plane or inclined arc surface sidewall, depending on actual requirements. Figure 1 The sidewall of the second through hole 51 is an inclined plane.

[0063] In traditional light-emitting diodes (LEDs), the dimensions of each second contact electrode and the corresponding second via are set to be equal. However, when the dimensions of the second contact electrode and the second via are equal, the different layers of the LED and the design of the electrode positions can easily lead to excessive current density per unit area and uneven current distribution, resulting in weak EOS (Effective Current) capability.

[0064] Based on the above, in this embodiment, please refer to Figure 1 The minimum distance between the second through hole 51 and the edge of the second contact electrode 21 is defined as the first spacing, and there are at least two second contact electrodes 21 and the second through hole 51 with unequal first spacings.

[0065] Specifically, by setting a larger first distance between some of the second contact electrodes 21 and the second through hole 51, and a smaller first distance between some of the second contact electrodes 21 and the second through hole 51, the current distribution within the light-emitting diode (LED) is adjusted, reducing the risk of electrode damage due to localized overheating and thus improving the overall EOS (Effective Current Distribution) capability of the LED. Preferably, the second contact electrodes 21 located in areas with relatively strong current distribution have a larger first distance, while the second contact electrodes 21 located in areas with relatively weak current distribution have a smaller first distance, so that the current is more rationally distributed between the second contact electrodes 21, further improving the EOS capability of the LED.

[0066] It should be noted that the first spacing refers to the minimum distance between the second through hole 51 and the edge of the second contact electrode 21. In a light-emitting diode, at least a portion of the second contact electrodes 21 are provided with corresponding second through holes 51. Here, "minimum distance" refers to the minimum value of the distance between the edge of a second contact electrode 21 and the second through hole 51 above that second contact electrode 21.

[0067] Furthermore, the first spacing can also be defined as the distance between the bottom edge of the second through hole 51 and the upper surface edge of the second contact electrode 21. Specifically, as... Figure 1 As shown, the second through-hole 51 can be a rounded hole that is wider at the top and narrower at the bottom, or other shapes. The second contact electrode 21 can also have vertical or inclined sidewalls to adapt to the performance requirements of different light-emitting diodes. Therefore, the first spacing here refers to the minimum distance between the bottom edge of the second through-hole 51 and the edge of the upper surface of the second contact electrode 21.

[0068] Preferably, the first spacing is between 2 and 10 micrometers to avoid the increased resistance due to an excessively large first spacing, which would affect the current transmission efficiency. At the same time, it avoids the risk of reliability abnormalities such as difficulty in manufacturing, electric field concentration, or thin metal barrier layer design on the sidewall of the second contact electrode 21 due to a small first spacing design, which would make it easy for moisture or solder paste to enter.

[0069] In an alternative implementation, such as Figure 3 , Figure 4 As shown, the first spacing includes a first sub-spacing d1 and a second sub-spacing d2, where the first sub-spacing d1 is greater than the second sub-spacing d2; the second contact electrode 21 with the second sub-spacing d2 is closer to the edge of the light-emitting diode than the second contact electrode 21 with the first sub-spacing d1.

[0070] It should be noted that there are two types of second contact electrodes 21 among all the second contact electrodes 21. One type of second contact electrode 21 has a relatively large first spacing, and the other type of second contact electrode 21 has a relatively small first spacing. The relatively large first spacing is defined as the first sub-spacing d1, and the relatively small first spacing is defined as the second sub-spacing d2. Here, "second contact electrode 21 with first sub-spacing d1" refers to a type of second contact electrode 21 in which the minimum distance between the edge of the second contact electrode 21 and the corresponding second through hole 51 is larger than the second sub-spacing d2; "second contact electrode 21 with second sub-spacing d2" refers to a type of second contact electrode 21 in which the minimum distance between the edge of the second contact electrode 21 and the corresponding second through hole 51 is smaller than the first sub-spacing d1.

[0071] In practical implementation, the current distribution closer to the edge of the LED is relatively weak, resulting in relatively low brightness. Therefore, by providing a second contact electrode 21 with a second sub-pitch d2, further reduction in brightness can be avoided. Conversely, the current distribution further away from the edge of the LED (i.e., the center of the LED) is relatively strong, making it prone to overcurrent and damage to the LED. Therefore, by providing a second contact electrode 21 with a first sub-pitch d1, current flow is promoted, overcurrent is prevented, and the EOS (Effective Optical Scale) of the LED is improved. Preferably, the difference between the first sub-pitch d1 and the second sub-pitch d2 is between 1 and 5 micrometers. While ensuring that the first sub-pitch d1 is large enough to improve the EOS, the difference is avoided from being too small, resulting in a large second sub-pitch d2 and a large second contact electrode 21 at the edge, leading to light absorption and reduced brightness. At the same time, the difference is avoided from being too large, resulting in a small second sub-pitch d2 and a small second contact electrode 21 at the edge, leading to reduced EOS.

[0072] By limiting the dimensions of the first sub-pitch d1 and the second sub-pitch d2 as described above, the photoelectric characteristics of the light-emitting diode can be reduced if the dimensions of the first sub-pitch d1 and the second sub-pitch d2 are set unreasonably.

[0073] In another alternative implementation, please refer to [link / reference needed]. Figure 3 , Figure 4The light-emitting diode (LED) also includes multiple first contact electrodes 22, with second contact electrodes 21 distributed between and around the multiple first contact electrodes 22 to ensure more uniform conductivity and thermal conductivity of the first contact electrodes 22 and second contact electrodes 21 on the LED. At least one second contact electrode 21 located between adjacent first contact electrodes 22 has a first sub-pitch d1; at least one second contact electrode 21 located around the multiple first contact electrodes 22 and closest to the edge of the LED has a second sub-pitch d2. Similarly, the current distribution is stronger in the region between adjacent first contact electrodes 22, therefore, second contact electrodes 21 with a first sub-pitch d1 are provided to prevent overcurrent and improve the EOS (Earning Power Loss) capability of the LED. Conversely, the current distribution is weaker in the region around the first contact electrodes 22 and closer to the LED, therefore, second contact electrodes 21 with a second sub-pitch d2 are provided to avoid absorption of brightness by the electrodes, further improving the brightness of the LED.

[0074] In other alternative embodiments, the number of second contact electrodes 21 with a second sub-pitch d2 is less than the number of second contact electrodes 21 with a first sub-pitch d1. That is, the number of second contact electrodes 21 with the first sub-pitch d1 is greater and they are disposed in regions with stronger current distribution, while the number of second contact electrodes 21 with the second sub-pitch d2 is less and they are disposed in regions with weaker current distribution, which can further improve the EOS capability and brightness of the light-emitting diode.

[0075] Further, the first spacing refers to the minimum distance between the edge of the second contact electrode 21 and the second through hole 51. To ensure that at least two second contact electrodes 21 have unequal first spacings, one approach is to change the size and area of ​​the second contact electrode 21 to make the first spacing unequal, while keeping the size and area of ​​the second through hole 51 equal. Alternatively, one approach is to change the size and area of ​​the second through hole 51 to make the first spacing unequal, while keeping the size and area of ​​the second contact electrode 21 equal. Furthermore, the size and area of ​​the second through hole 51 and the second contact electrode 21 can be changed simultaneously to ensure that at least two second contact electrodes 21 have unequal first spacings. In this embodiment, it is preferable that the cross-sectional areas of the second through holes 51 corresponding to each second contact electrode 21 are equal on the same horizontal plane, and that at least two second contact electrodes 21 have unequal cross-sectional areas on the same horizontal plane. That is, by changing the area of ​​the second contact electrode 21, the first spacings corresponding to different second contact electrodes 21 are made unequal.

[0076] Preferably, on the same horizontal plane, the second contact electrode 21 with a smaller cross-sectional area is closer to the edge of the light-emitting diode (LED) than the second contact electrode 21 with a larger cross-sectional area. Specifically, placing the second contact electrode 21 with a smaller cross-sectional area closer to the edge of the LED reduces the absorption of light by the electrode, thereby increasing brightness. Placing the second contact electrode 21 with a larger cross-sectional area further away from the edge of the LED (i.e., the central region of the LED) promotes current flow and improves EOS (Electrical Optimization) capability.

[0077] Preferably, the average first distance between all the second contact electrodes 21 closest to the edge of the LED and the second through hole 51 is smaller than the average first distance between all the second contact electrodes 21 relatively far from the edge of the LED and the second through hole 51. Similarly, this arrangement can effectively improve the EOS capability and brightness of the LED.

[0078] In one embodiment, the second contact electrode 21 has a diameter, and at least two second contact electrodes 21 have unequal diameters. By designing different diameters for the second contact electrodes 21, the current density distribution and optical effect within the light-emitting diode (LED) can be further effectively adjusted. Specifically, the diameter of the second contact electrode 21 includes a first diameter W1 and a second diameter W2, wherein the first diameter W1 is larger than the second diameter W2, and the second contact electrode 21 with the second diameter W2 is closer to the edge of the LED than the second contact electrode 21 with the first diameter W1. That is, by designing a smaller second diameter W2 for the LED edge where the current distribution is relatively weak, and designing a larger first diameter W1 for the LED center where the current distribution is relatively strong, the current is more rationally distributed on the LED, thereby improving the EOS (Electronic Optical Detection) capability. Preferably, the first diameter W1 is between 18 and 30 micrometers, and the second diameter W2 is between 15 and 25 micrometers.

[0079] By defining the dimensions of the second contact electrode 21 and the second through hole 51 at different positions as described above, the current distribution of the light-emitting diode can be optimized, thereby improving the EOS capability of the light-emitting diode.

[0080] Example 2

[0081] Please see Figure 5 Based on Embodiment 1, the light-emitting diode further includes multiple current-blocking layers 61 located below the second contact electrode 21; the orthogonal projection of the second contact electrode 21 onto the epitaxial structure 10 lies within the orthogonal projection range of the current-blocking layers 61 onto the epitaxial structure 10. Please refer to [link to previous text]. Figures 1-5 The minimum distance between the second through hole 51 located above the second contact electrode 21 and the edge of the current blocking layer 61 located below the second contact electrode 21 is defined as the second spacing; there are at least two second contact electrodes 21 with unequal second spacings.

[0082] In specific implementation, to ensure that at least two second contact electrodes 21 have unequal second spacings, one approach is to change the size and area of ​​the current blocking layer 61 while keeping the size and area of ​​the second through-hole 51 equal, thus making the first spacing unequal. Alternatively, while keeping the size and area of ​​the current blocking layer 61 equal, the size and area of ​​the second through-hole 51 can be changed to make the first spacing unequal. Furthermore, the size and area of ​​both the second through-hole 51 and the current blocking layer 61 can be changed simultaneously to ensure that at least two second contact electrodes 21 have unequal second spacings. In this embodiment, it is preferable that the cross-sectional area of ​​the second through-hole 51 above each second contact electrode 21 is the same, and the cross-sectional area of ​​the current blocking layer 61 below each second contact electrode 21 is different to achieve unequal second spacings between the two second contact electrodes 21.

[0083] In this embodiment, the current distribution within the light-emitting diode is adjusted by setting the second spacing between at least two second contact electrodes 21 to be unequal, thereby further improving the EOS (Effective Occurrence Limit) capability of the light-emitting diode. Preferably, the second contact electrode 21 located at a position with relatively strong current distribution has a larger second spacing, while the second contact electrode 21 located at a position with relatively weak current distribution has a smaller second spacing. As an example, the second spacing is between 5 and 15 micrometers.

[0084] Further, the second spacing is defined as the distance between the bottom edge of the second via 51 located above the second contact electrode 21 and the upper surface edge of the current blocking layer 61 located below the second contact electrode 21. Specifically, the second via 51 can be in the shape of an inverted frustum (wider at the top and narrower at the bottom) or other shapes to accommodate the performance requirements of different light-emitting diodes. Therefore, the first spacing here refers to the minimum distance between the bottom edge of the second via 51 and the upper surface edge of the current blocking layer 61. For example... Figure 1 In the middle, the second through hole 51 is shaped like an inverted frustum.

[0085] In an alternative implementation, please refer to Figure 5 The second spacing includes a third sub-spacing d3 and a fourth sub-spacing d4, with the third sub-spacing d3 being larger than the fourth sub-spacing d4. The second contact electrode 21 with the fourth sub-spacing d4 is closer to the edge of the light-emitting diode than the second contact electrode 21 with the third sub-spacing d3. Preferably, the difference between the third sub-spacing d3 and the fourth sub-spacing d4 is between 1 and 5 micrometers.

[0086] It should be noted that there are two types of second contact electrodes 21 among all the second contact electrodes 21. One type of second contact electrode 21 has a relatively large second spacing, and the other type of second contact electrode 21 has a relatively small second spacing. The relatively large second spacing is defined as the third sub-spacing d3, and the relatively small second spacing is defined as the fourth sub-spacing d4. Here, "second contact electrode 21 with third sub-spacing d3" refers to a type of second contact electrode 21 in which the minimum distance between the second through hole 51 above the second contact electrode 21 and the current blocking layer 61 below the second contact electrode 21 is larger than the fourth sub-spacing d4; "second contact electrode 21 with fourth sub-spacing d4" refers to a type of second contact electrode 21 in which the minimum distance between the second through hole 51 above the second contact electrode 21 and the current blocking layer 61 below the second contact electrode 21 is smaller than the third sub-spacing d3.

[0087] In a specific implementation, the second contact electrode 21 with a fourth sub-pitch d4 is placed in the region near the edge of the light-emitting diode, and the second contact electrode 21 with a third sub-pitch d3 is placed in the region far from the edge of the light-emitting diode, so as to further improve the EOS capability and brightness of the light-emitting diode.

[0088] In another alternative implementation, please refer to Figure 2 , Figure 4 The light-emitting diode also includes a plurality of first contact electrodes 22; second contact electrodes 21 are distributed between the plurality of first contact electrodes 22 and around the plurality of first contact electrodes 22; at least one second contact electrode 21 located between adjacent first contact electrodes 22 has a third sub-spacing d3; at least one second contact electrode 21 located around the plurality of first contact electrodes 22 and closest to the edge of the light-emitting diode has a fourth sub-spacing d4. With the above configuration, the EOS capability and brightness of the light-emitting diode can also be improved.

[0089] In other alternative embodiments, the second spacing may be defined such that the number of second contact electrodes 21 having a second sub-spacing d2 is less than the number of second contact electrodes 21 having a first sub-spacing d1. Alternatively, the average second spacing corresponding to the second contact electrode 21 closest to the edge of the light-emitting diode is less than the average second spacing corresponding to the second contact electrode 21 relatively far from the edge of the light-emitting diode.

[0090] It should also be noted that the setting of the second spacing in this embodiment is analogous to the setting of the first spacing in the first embodiment above. For details, please refer to the setting of the first spacing in the first embodiment. This embodiment will not repeat the details.

[0091] Example 3

[0092] Unlike Embodiments 1 and 2, the first distance between the second contact electrode 21 and the second through hole 51 is equal, but at least two of the second through holes 51 have unequal diameters. Because conventional LEDs have weak EOS (Effective Light Emitting Diode) capability due to the equal dimensions of each second contact electrode and second through hole, this Embodiment 3 designs the first distance between the second contact electrode 21 and the second through hole 51 to be equal. By adjusting the unequal diameters of the second through holes 51, the unequal diameters of the second contact electrodes 21 are controlled, thereby effectively improving the EOS capability.

[0093] Specifically, by setting the diameter of the second through hole 51 corresponding to some of the second contact electrodes 21 to be larger and the diameter of the second through hole 51 corresponding to some of the second contact electrodes 21 to be smaller, the current distribution in the light-emitting diode is adjusted, the risk of electrode damage due to local overheating is reduced, and the overall EOS capability of the light-emitting diode is improved.

[0094] Better, such as Figure 6 As shown, the diameter of the second through hole 51 includes a third diameter W3 and a fourth diameter W4, wherein the third diameter W3 is larger than the fourth diameter W4. The second through hole 51 with the fourth diameter W4 is closer to the edge of the light-emitting diode than the second through hole 51 with the third diameter W3.

[0095] It should be noted that among all the second through holes 51, there are two types of second through holes 51: one type has a relatively large diameter, and the other type has a relatively small diameter. The relatively larger diameter is defined as the third diameter W3, and the relatively smaller diameter is defined as the fourth diameter W4. Here, "second through hole 51 with third diameter W3" refers to the type of second through hole 51 whose diameter is larger than the fourth diameter W4, and "second through hole 51 with fourth diameter W4" refers to the type of second through hole 51 whose diameter is smaller than the third diameter W3.

[0096] In practice, the current distribution closer to the edge of the LED is relatively weak, resulting in lower brightness. Therefore, assuming equal initial spacing, the diameter of the second contact electrode 21 is controlled to be smaller by providing a second through-hole 51 with a fourth diameter W4, thus avoiding further brightness reduction due to electrode coverage. Conversely, the current distribution further away from the edge of the LED (i.e., the center of the LED) is relatively strong, making it prone to overcurrent and damage. Therefore, assuming equal initial spacing, the diameter of the second contact electrode 21 is controlled to be larger by providing a second through-hole 51 with a third diameter W3, thereby promoting greater current flow, preventing overcurrent, and improving the EOS (Effective Current) capability of the LED.

[0097] The dimensions of the third diameter W3 and the fourth diameter W4 can be designed reasonably according to actual needs, and are not limited here.

[0098] Example 4

[0099] Please see Figure 7 Based on Embodiments 1, 2, and 3, the light-emitting diode further includes a first connecting electrode 32 and a second connecting electrode 31. The first connecting electrode 32 is located on the insulating layer 50 and is electrically connected to the first contact electrode 22; the second connecting electrode 31 is located on the insulating layer 50 and is electrically connected to the second contact electrode 21. Specifically, the first connecting electrode 32 and the second connecting electrode 31 cover the insulating layer 50 and are electrically connected to the first contact electrode 22 and the second contact electrode 21 below by filling the first through-hole 52 and the second through-hole 51 opened in the insulating layer 50.

[0100] Preferably, the first connecting electrode 32 and / or the second connecting electrode 31 comprises multiple alternating stacked Al / Ti layers, wherein the number of stacked pairs of the Al / Ti layers is 4 to 8, and in this embodiment, the number of stacked pairs is preferably 5 to 7. That is, by increasing the number of stacked pairs of the Al / Ti layers, not only can the electrode thickness be increased and the thermal conductivity of the electrode optimized, thereby improving the heat dissipation capacity of the chip, but the EOS capability can also be effectively improved. More preferably, the thickness of the Al layer in the Al / Ti stack is greater than the thickness of the Ti layer. By designing a thicker Al layer, not only can the reflection effect and thermal conductivity be improved and the chip voltage reduced, but the ductility and tensile strength of Al metal can also be used to act as a stress buffer, preventing electrode breakage or detachment and increasing reliability.

[0101] In other embodiments, the thickness of the first connecting electrode 32 and / or the second connecting electrode 31 is between 22,500 and 27,500 angstroms. This thickness limit can effectively reduce the chip voltage and improve the chip's photoelectric efficiency.

[0102] Example 5

[0103] The present invention also provides a light-emitting device that employs a light-emitting diode as described in any of the above embodiments, which can effectively improve the performance of the light-emitting device. The specific structure, function, and role of the light-emitting diode are as described above and will not be repeated here.

[0104] In summary, compared with the prior art, the light-emitting diode and light-emitting device provided by the present invention can effectively improve the EOS capability of the light-emitting diode by designing the second contact electrode and the second through hole, and avoid the risk of structural burn-out of the light-emitting diode under overvoltage conditions, which would cause the light-emitting diode to fail.

[0105] Furthermore, those skilled in the art should understand that although many problems exist in the prior art, each embodiment or technical solution of the present invention can be improved in only one or a few aspects, without necessarily solving all the technical problems listed in the prior art or the background art simultaneously. Those skilled in the art should understand that any content not mentioned in a claim should not be construed as a limitation on that claim.

[0106] Although this document frequently uses terms such as epitaxial structure, first contact electrode, second contact electrode, insulating layer, second via, first pitch, second pitch, first sub-pitch, second sub-pitch, third sub-pitch, and fourth sub-pitch, the possibility of using other terms is not excluded. These terms are used merely for the convenience of describing and explaining the essence of the invention; interpreting them as any additional limitation would contradict the spirit of the invention. The terms "first," "second," etc., in the specification, claims, and accompanying drawings of the embodiments of the invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0107] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions 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 by, The light emitting diode comprises: an epitaxial structure comprising a first semiconductor layer, an active layer and a second semiconductor layer stacked in sequence; a plurality of second contact electrodes distributed above the second semiconductor layer and electrically connected to the second semiconductor layer; an insulating layer covering at least part of the second contact electrodes and the epitaxial structure; the insulating layer comprises second through holes exposing part of the surface of the second contact electrodes; the second through holes and the edges of the second contact electrodes have a minimum distance, which is a first spacing; the first spacing of at least two of the second contact electrodes and the second through holes is not equal; the first spacing comprises a first sub-spacing and a second sub-spacing, the first sub-spacing is greater than the second sub-spacing; the second contact electrodes with the second sub-spacing are closer to the edge of the light emitting diode than the second contact electrodes with the first sub-spacing.

2. The light emitting diode of claim 1, wherein: The first spacing is between 2-10 microns.

3. The light emitting diode of claim 1, wherein: The first spacing is defined as the distance between the bottom edge of the second through hole and the upper surface edge of the second contact electrode.

4. The light emitting diode of claim 1, wherein: The light emitting diode further comprises a plurality of first contact electrodes, the plurality of first contact electrodes are distributed above the first semiconductor layer and electrically connected to the first semiconductor layer; the second contact electrodes are distributed between the plurality of first contact electrodes and the periphery of the plurality of first contact electrodes; at least one second contact electrode located between adjacent first contact electrodes has a first sub-spacing; at least one second contact electrode located at the periphery of the plurality of first contact electrodes and closest to the edge of the light emitting diode has a second sub-spacing.

5. The light emitting diode according to claim 1 or 4, wherein: The difference between the first sub-spacing and the second sub-spacing is between 1-5 microns.

6. The light emitting diode of claim 1 or 4, wherein: The number of second contact electrodes with the second sub-spacing is less than the number of second contact electrodes with the first sub-spacing.

7. The light emitting diode of claim 1, wherein: The cross-sectional area of the second through hole corresponding to each second contact electrode on the same horizontal plane is equal, and the cross-sectional area of at least two second contact electrodes on the same horizontal plane is not equal.

8. The light emitting diode of claim 7, wherein: On the same horizontal plane, the second contact electrode with a smaller cross-sectional area is closer to the edge of the light emitting diode than the second contact electrode with a larger cross-sectional area.

9. The light emitting diode of claim 1, wherein: The second contact electrodes have diameters, and the diameters of at least two second contact electrodes are not equal.

10. The light emitting diode of claim 9, wherein: The diameters of the second contact electrodes comprise a first diameter and a second diameter, the first diameter is greater than the second diameter, and the second contact electrodes with the second diameter are closer to the edge of the light emitting diode than the second contact electrodes with the first diameter; the first diameter is between 18-30 microns, and the second diameter is between 15-25 microns.

11. The light emitting diode of claim 1, wherein: The light emitting diode further comprises a plurality of current blocking layers under the second contact electrodes; a normal projection of the second contact electrodes on the epitaxial structure is within a normal projection range of the current blocking layers on the epitaxial structure; a minimum distance between a second via hole above the second contact electrode and an edge of the current blocking layer under the second contact electrode is defined as a second spacing; at least two second spacings corresponding to the second contact electrodes are not equal.

12. The light emitting diode of claim 11, wherein: The second spacing is between 5-15 microns.

13. The light emitting diode of claim 11, wherein: The second spacing is defined as a distance between a bottom edge of the second via hole above the second contact electrode and an upper surface edge of the current blocking layer under the second contact electrode.

14. The light emitting diode of claim 11, wherein: The second spacing comprises a third sub-spacing and a fourth sub-spacing, the third sub-spacing is greater than the fourth sub-spacing; the second contact electrode with the fourth sub-spacing is closer to an edge of the light emitting diode than the second contact electrode with the third sub-spacing.

15. The light emitting diode of claim 11, wherein: The second spacing comprises a third sub-spacing and a fourth sub-spacing, the third sub-spacing is greater than the fourth sub-spacing; the light emitting diode further comprises a plurality of first contact electrodes, the plurality of first contact electrodes are distributed above the first semiconductor layer and electrically connected to the first semiconductor layer; the second contact electrodes are distributed between the plurality of first contact electrodes and a periphery of the plurality of first contact electrodes; at least one second contact electrode between adjacent first contact electrodes has the third sub-spacing; at least one second contact electrode in the periphery of the plurality of first contact electrodes and closest to an edge of the light emitting diode has the fourth sub-spacing.

16. The light emitting diode of claim 14 or 15, wherein: The difference between the third sub-spacing and the fourth sub-spacing is between 1-5 microns.

17. The light emitting diode of claim 1, wherein: The light emitting diode further comprises a plurality of first contact electrodes, the plurality of first contact electrodes are distributed above the first semiconductor layer and electrically connected to the first semiconductor layer; a plurality of second contact electrodes are uniformly distributed around each first contact electrode.

18. The light emitting diode of claim 17, wherein: The insulating layer further comprises a first via hole exposing a part of a surface of the first contact electrode, a minimum distance between the first contact electrode and the first via hole is defined as a third spacing, the third spacing is smaller than the first spacing.

19. The light emitting diode of claim 17, wherein, The light emitting diode further comprises: a current spreading layer between the second contact electrodes and the second semiconductor layer; a first connection electrode on the insulating layer and electrically connected to the plurality of first contact electrodes; a second connection electrode on the insulating layer and electrically connected to the plurality of second contact electrodes.

20. A light emitting diode, comprising: The light emitting diode comprises: an epitaxial structure, the epitaxial structure comprises a first semiconductor layer, an active layer and a second semiconductor layer stacked in sequence; a plurality of second contact electrodes distributed above the second semiconductor layer and electrically connected to the second semiconductor layer; an insulating layer covering at least part of the second contact electrode and the epitaxial structure; the insulating layer comprising second through-holes exposing part of the surface of the second contact electrode; the second through-holes having a minimum distance to the edge of the second contact electrode, the minimum distance being a first distance; the first distance of the second contact electrode to the second through-holes being equal; at least two of the second through-holes having a different diameter; the diameter of the second through-holes comprising a third diameter and a fourth diameter, the third diameter being larger than the fourth diameter; the second through-holes having the fourth diameter being closer to the edge of the light emitting diode than the second through-holes having the third diameter.

21. A light-emitting device, characterized in that: A light emitting diode as claimed in any one of the claims 1-20.

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