High-brightness light emitting diode and method of fabricating the same

Abstract

The present disclosure provides a high-brightness light-emitting diode and a preparation method thereof, and belongs to the technical field of optoelectronic manufacturing. The light-emitting diode comprises a light-emitting structure and a first electrode, wherein the first electrode is located on the surface of the light-emitting structure; the first electrode comprises a pad and an extension strip, one end of the extension strip is connected with the pad, the extension strip comprises a plurality of nanometer conductive wires and a plurality of conductive blocks, the plurality of conductive blocks are arranged at intervals, and adjacent conductive blocks are connected through the nanometer conductive wires. The adjacent conductive blocks are connected through the nanometer conductive wires, so that the extension strip still has the original conductive effect, and at the same time, since the diameter of the nanometer conductive wire is small, the nanometer conductive wire basically does not block the light, and therefore the brightness of the light-emitting diode can be further improved.

Description

Technical Field

[0001] This disclosure relates to the field of optoelectronic manufacturing technology, and in particular to a high-brightness light-emitting diode and its fabrication method. Background Technology

[0002] Light-emitting diodes (LEDs) are highly influential new products in the optoelectronics industry. They are characterized by their small size, long lifespan, rich and colorful colors, and low energy consumption, and are widely used in display devices.

[0003] A light-emitting diode (LED) typically consists of a light-emitting structure and electrodes, with the electrodes positioned on the surface of the light-emitting structure. The electrodes are usually made of metal, which can partially block the light emitted by the light-emitting structure, thus hindering the improvement of the LED's brightness. Summary of the Invention

[0004] This disclosure provides a high-brightness light-emitting diode and its fabrication method, which can further improve the brightness of the light-emitting diode. The technical solution is as follows:

[0005] On one hand, embodiments of this disclosure provide a light-emitting diode, the light-emitting diode including a light-emitting structure and a first electrode, the first electrode being located on the surface of the light-emitting structure;

[0006] The first electrode includes a pad and an extension strip. One end of the extension strip is connected to the pad. The extension strip includes multiple nano-conductive wires and multiple conductive blocks. The multiple conductive blocks are arranged at intervals, and adjacent conductive blocks are connected through the nano-conductive wires.

[0007] Optionally, each of the nanoconductive wires is connected to the plurality of conductive blocks; or, the nanoconductive wires are located between adjacent conductive blocks, and both ends are connected to the adjacent conductive blocks.

[0008] Optionally, the nano-conductive wire includes an inner conductive wire, a first conductive coating layer, and a second conductive coating layer, wherein the first conductive coating layer covers the inner conductive wire, and the second conductive coating layer covers the first conductive coating layer.

[0009] Optionally, the inner conductive wire is made of copper, the first conductive coating layer is made of copper-gold alloy, and the second conductive coating layer is made of gold.

[0010] Optionally, the diameter of the inner conductive wire is 0.1 μm to 0.3 μm, the thickness of the first conductive coating layer is 0.01 μm to 0.03 μm, and the thickness of the second conductive coating layer is 0.01 μm to 0.03 μm.

[0011] Optionally, the conductive block comprises a chromium layer, a titanium layer, a first gold layer, and a second gold layer stacked sequentially.

[0012] Optionally, the nanoconductive wire is located between the first gold layer and the second gold layer.

[0013] Optionally, the surface of the first gold layer away from the titanium layer has a plurality of strip grooves, and the nanoconductive wires are located in the plurality of strip grooves.

[0014] Optionally, the light-emitting structure includes an epitaxial layer and a transparent conductive layer, the transparent conductive layer being located on the surface of the epitaxial layer, the first electrode being located on the transparent conductive layer, and the pads being electrically contacted with the epitaxial layer through vias;

[0015] The annular region in contact with the pads of the transparent conductive layer includes at least one of the following:

[0016] Multiple laser annealing zones;

[0017] Multiple high-tin composition regions, wherein the tin content within the high-tin composition regions is higher than the tin content outside the high-tin composition regions;

[0018] Multiple crystal orientation difference regions, wherein the crystal orientation within the crystal orientation difference regions is different from the crystal orientation outside the crystal orientation difference regions.

[0019] On the other hand, this disclosure also provides a method for fabricating a light-emitting diode, the method comprising:

[0020] Provide a light-emitting structure;

[0021] A first electrode is formed on the surface of the light-emitting structure. The first electrode includes a pad and an extension strip. One end of the extension strip is connected to the pad. The extension strip includes multiple nano-conductive wires and multiple conductive blocks. The multiple conductive blocks are arranged at intervals, and adjacent conductive blocks are connected through the nano-conductive wires.

[0022] The beneficial effects of the technical solutions provided in this disclosure include at least the following:

[0023] By configuring the extension strip of the first electrode into a structure comprising multiple nano-conductive wires and multiple conductive blocks, wherein the multiple conductive blocks are arranged at intervals and adjacent conductive blocks are connected by nano-conductive wires, the extension strip still has the original conductive function. At the same time, since the nano-conductive wires have a small diameter, they do not block light, thus further improving the brightness of the light-emitting diode. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of a light-emitting diode in related technologies;

[0026] Figure 2 This is a schematic diagram of the structure of a light-emitting diode provided in an embodiment of this disclosure;

[0027] Figure 3 This is a schematic cross-sectional view of a nanoconductive wire provided in an embodiment of this disclosure;

[0028] Figure 4 This is a schematic diagram of the connection between a conductive block and a nano-conductive wire provided in an embodiment of this disclosure;

[0029] Figure 5 This is a schematic diagram of the connection between a conductive block and a nano-conductive wire provided in an embodiment of this disclosure;

[0030] Figure 6 This is a cross-sectional view of a light-emitting diode provided in an embodiment of this disclosure;

[0031] Figure 7 This is a schematic diagram of the structure of a transparent conductive layer provided in an embodiment of this disclosure;

[0032] Figure 8 This is a flowchart of a method for fabricating a light-emitting diode according to an embodiment of this disclosure;

[0033] Figure 9 This is a flowchart of a method for fabricating a light-emitting diode according to an embodiment of this disclosure;

[0034] Figure 10 This is a schematic diagram of the fabrication process of a light-emitting diode provided in an embodiment of this disclosure;

[0035] Figure 11 This is a schematic diagram of the fabrication process of a light-emitting diode provided in an embodiment of this disclosure;

[0036] Figure 12 This is a schematic diagram of the fabrication process of a light-emitting diode provided in an embodiment of this disclosure;

[0037] Figure 13 This is a schematic diagram of the fabrication process of a light-emitting diode provided in an embodiment of this disclosure;

[0038] Figure 14This is a schematic diagram of the fabrication process of a light-emitting diode provided in an embodiment of this disclosure. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this disclosure clearer, the embodiments of this disclosure will be described in further detail below with reference to the accompanying drawings.

[0040] Figure 1 This is a schematic diagram of the structure of a light-emitting diode (LED) in related technologies. For example... Figure 1 As shown, the light-emitting diode includes a light-emitting structure 30 and a first electrode 10 and a second electrode 20 located on the light-emitting structure 30. Both the first electrode 10 and the second electrode 20 are connected to the light-emitting structure 30.

[0041] The first electrode 10 includes a pad 11 and an extension strip 12. One end of the extension strip 12 is connected to the pad 11, and the other end extends away from the pad 11. The first electrode 10 is usually located in the light-emitting area of ​​the light-emitting structure 30, and will block the light emitted by the light-emitting structure 30 to a certain extent, thereby affecting the brightness of the light-emitting diode.

[0042] Figure 2 This is a schematic diagram of the structure of a light-emitting diode provided in an embodiment of this disclosure. For example... Figure 2 As shown, the light-emitting diode includes a light-emitting structure 30 and a first electrode 10. The first electrode 10 is located on the surface of the light-emitting structure 30. The extension strip 12 of the first electrode 10 includes a plurality of nano-conductive wires 122 and a plurality of conductive blocks 121. The plurality of conductive blocks 121 are arranged at intervals, and adjacent conductive blocks 121 are connected by nano-conductive wires 122.

[0043] By configuring the extension strip 12 of the first electrode 10 into a structure comprising multiple nano-conductive wires 122 and multiple conductive blocks 121, wherein the multiple conductive blocks 121 are arranged at intervals and adjacent conductive blocks 121 are connected by nano-conductive wires 122, the extension strip 12 retains its original conductive function, while the small diameter of the nano-conductive wires 122 further enhances its conductivity. Figure 2 Compared to the extension bar 12 in the middle Figure 1 The extension strip 12 in the LED blocks light less, thus further improving the brightness of the LED.

[0044] In some examples, each nanowire 122 is connected to multiple conductive blocks 121.

[0045] That is, the nano-conductive wires 122 are arranged along the length of the extension strip 12 and connected to multiple conductive blocks 121 in sequence, which makes it more convenient to arrange the nano-conductive wires 122.

[0046] As an example, the nanoconductive wire 122 may be located on the surface of the conductive block 121 and connected to the surface of the conductive block 121.

[0047] As another example, the nanoconductive wires 122 can also be located inside the conductive block 121, penetrating through the conductive block 121. That is, the nanoconductive wires 122 connect multiple conductive blocks 121 together.

[0048] In other examples, the nanoconductive wires 122 are located between adjacent conductive blocks 121, and both ends are connected to the adjacent conductive blocks 121. That is, the nanoconductive wires 122 are divided into multiple groups, with a group of nanoconductive wires 122 arranged between each pair of adjacent conductive blocks 121, and electrically connected through the group of nanoconductive wires 122.

[0049] Figure 3 This is a schematic cross-sectional view of a nanoconductive wire provided in an embodiment of this disclosure. For example... Figure 3 As shown, the nano-conductive wire 122 includes an inner conductive wire 1221, a first conductive coating layer 1222 and a second conductive coating layer 1223. The first conductive coating layer 1222 covers the inner conductive wire 1221, and the second conductive coating layer 1223 covers the first conductive coating layer 1222.

[0050] By setting the nanoconductive wire 122 into a multi-layered structure, different materials can be used to make the inner conductive wire 1221, the first conductive coating layer 1222, and the second conductive coating layer 1223. This makes it easier to use suitable materials to make the nanoconductive wire 122 have good conductivity, sufficient structural strength, and be less prone to breakage. At the same time, it also has good resistance to corrosion and oxidation, further improving the reliability of the nanoconductive wire 122.

[0051] For example, the inner conductive wire 1221 is made of copper, the first conductive coating layer 1222 is made of a copper-gold alloy, and the second conductive coating layer 1223 is made of gold. Copper, gold, and copper-gold alloys all have good electrical and thermal conductivity. Using copper to make the inner conductive wire 1221 reduces the amount of gold used, which helps to reduce costs. The first conductive coating layer 1222 is made of a copper-gold alloy, for example, a copper-gold alloy with a gold content of 20% by mass, which serves as a transition, enhances the adhesion of the second conductive coating layer 1223, and prevents the second conductive coating layer 1223 from peeling off. Gold has good stability and is resistant to corrosion and oxidation. Using gold to make the second conductive coating layer 1223 helps to improve the corrosion and oxidation resistance of the nano-conductive wire 122. Gold has very low contact resistance. Using gold to make the second conductive coating layer 1223 also facilitates the connection between the nano-conductive wire 122 and the conductive block 121.

[0052] Optionally, the diameter of the inner conductive line 1221 is 0.1 μm to 0.3 μm. The thickness of the first conductive coating layer 1222 is 0.01 μm to 0.03 μm. The thickness of the second conductive coating layer 1223 is 0.01 μm to 0.03 μm.

[0053] For example, the diameter of the inner conductive line 1221 is 0.2 μm. The thickness of the first conductive coating layer 1222 is 0.02 μm. The thickness of the second conductive coating layer 1223 is 0.02 μm.

[0054] The diameter of the inner conductive wire 1221 is set to be larger than the thickness of the first conductive coating layer 1222 and the second conductive coating layer 1223. Most of the nano-conductive wire 122 is made of copper, which is relatively inexpensive. Copper has lower ductility than gold but higher strength, making it more suitable for fabricating a larger diameter inner conductive wire 1221, thus improving the structural strength of the nano-conductive wire 122. Gold has high ductility, allowing for the fabrication of a thinner second conductive coating layer 1223, which helps reduce the diameter of the nano-conductive wire 122, further reducing light obstruction and improving the brightness of the light-emitting diode.

[0055] Figure 4 This is a schematic diagram illustrating the connection between a conductive block and nanowires according to an embodiment of this disclosure. Figure 4 As shown, the conductive block 121 includes a chromium layer 1211, a titanium layer 1212, a first gold layer 1213, and a second gold layer 1214 stacked sequentially.

[0056] For example, the thickness of the chromium layer 1211 is 0.002 μm to 0.004 μm, the thickness of the titanium layer 1212 is 0.4 μm to 0.6 μm, the thickness of the first gold layer 1213 is 0.5 μm to 2 μm, and the thickness of the second gold layer 1214 is 0.2 μm to 0.4 μm. As another example, the thickness of the chromium layer 1211 is 0.003 μm, the thickness of the titanium layer 1212 is 0.5 μm, the thickness of the first gold layer 1213 is 1 μm, and the thickness of the second gold layer 1214 is 0.3 μm.

[0057] The chromium layer 1211 has good reflectivity, which can reflect blocked light back into the light-emitting structure 30, and then emit it after several reflections, which helps to improve the brightness of the light-emitting diode. The titanium layer 1212 has good adhesion, which reliably adheres the first gold layer 1213 to the chromium layer 1211. The first gold layer 1213 and the second gold layer 1214 are used to connect with the nanoconductive wires 122.

[0058] For example, the nano-conductive wire 122 is located between the first gold layer 1213 and the second gold layer 1214. During fabrication, after the first gold layer 1213 is formed, the nano-conductive wire 122 is placed on the first gold layer 1213, and then the second gold layer 1214 is formed. The first gold layer 1213 and the second gold layer 1214 become a whole, and the nano-conductive wire 122 is embedded in the whole formed by the first gold layer 1213 and the second gold layer 1214, making the connection between the nano-conductive wire 122 and the conductive block 121 more stable.

[0059] Figure 5 This is a schematic diagram of the connection between a conductive block and a nanowire provided in an embodiment of this disclosure, as shown below. Figure 5 As shown, the surface of the first gold layer 1213 away from the titanium layer 1212 has multiple strip grooves 1213a, and the nano-conductive wires 122 are located in the multiple strip grooves 1213a.

[0060] Multiple strips 1213a are parallel to each other. On the surface of the first gold layer 1213 away from the titanium layer 1212, the strips 1213a extend from one of two opposite sides to the other.

[0061] By providing the strip grooves 1213a, the nano-conductive wires 122 can be positioned during arrangement, facilitating their placement. During arrangement, the two ends of each nano-conductive wire 122 are located within the strip grooves 1213a of the first gold layer 1213 of the two conductive blocks 121. At least one nano-conductive wire 122 can be accommodated within the same strip groove 1213a.

[0062] For example, the cross-section of the strip groove 1213a is V-shaped. In other examples, the cross-section of the strip groove 1213a may also be other shapes, such as semi-circular, semi-elliptical, etc.

[0063] The depth of the groove 1213a can be 0.4 μm to 0.6 μm. As an example, in this embodiment of the present disclosure, the depth of the groove 1213a is 0.5 μm.

[0064] Optionally, on the same first gold layer 1213, multiple strip grooves 1213a can be arranged at equal intervals, and each strip groove 1213a contains the same number of nano-conductive wires 122, so that the distribution of nano-conductive wires 122 is more uniform, which is beneficial to improving the conductivity of the extension strip 12.

[0065] Figure 6 This is a cross-sectional view of a light-emitting diode provided in an embodiment of this disclosure, corresponding to... Figure 2 Section AA in the diagram. Figure 6 As shown, the light-emitting structure 30 of the light-emitting diode includes an epitaxial layer 31 and a transparent conductive layer 32.

[0066] A transparent conductive layer 32 is located on the surface of the epitaxial layer 31, and a first electrode 10 is located on the transparent conductive layer 32. The transparent conductive layer 32 has vias, and the pads 11 of the first electrode 10 are electrically in contact with the epitaxial layer 31 through the vias.

[0067] The transparent conductive layer 32 can be indium tin oxide (ITO).

[0068] The surface of the epitaxial layer 31 may also have a current blocking layer 33, and a transparent conductive layer 32 covers the current blocking layer 33. The current blocking layer 33 is annular and arranged around the via.

[0069] Figure 7 This is a schematic diagram of a transparent conductive layer according to an embodiment of the present disclosure. The area of ​​the transparent conductive layer 32 that contacts the first electrode 10 is shown in dashed lines. The pad 11 contacts the area around the via of the transparent conductive layer 32, and the contact area is annular. The annular area where the transparent conductive layer 32 contacts the pad 11 may have multiple sub-regions. These sub-regions may include one or more of multiple laser annealing regions 321, multiple high-tin composition regions 322, and multiple crystal orientation difference regions 323.

[0070] Among them, the laser annealing zone 321 is the area that has undergone laser annealing treatment. By performing laser annealing, multiple laser annealing zones 321 are formed. Laser annealing can improve the crystallinity, surface roughness and photoelectric properties of the transparent conductive layer 32. After laser annealing, the structure of the laser annealing zone 321 is more compact and the contact resistance between it and the pad 11 is smaller.

[0071] The high tin content region 322 is a region with a higher tin content than the adjacent regions. The tin content within the high tin content region 322 is higher than the tin content outside the high tin content region 322; for example, the tin content of the high tin content region 322 is 60%. In the transparent conductive layer 32, the regions with higher tin content have greater stability, making the electrical connection between the pad 11 and the transparent conductive layer 32 more stable and reliable.

[0072] The crystal orientation difference region 323 is a region with a different crystal orientation from the adjacent region. The crystal orientation within the crystal orientation difference region 323 is different from the crystal orientation outside the crystal orientation difference region 323. The different crystal orientations will cause the conductivity of the transparent conductive layer 32 to vary in different directions. By setting different crystal orientations, the overall conductivity difference along various directions in the area where the pad 11 contacts the transparent conductive layer 32 is smaller, which is also beneficial to the spread of current in the transparent conductive layer 32.

[0073] In this example, the light-emitting diode also includes a substrate 40, an epitaxial layer 31 located on the bearing surface of the substrate 40, and a transparent conductive layer 32 located on the surface of the epitaxial layer 31 away from the substrate 40. In other examples, the substrate 40 may be removed to form a light-emitting diode without a substrate 40.

[0074] As an example, such as Figure 6 As shown, the epitaxial layer 31 may include an N-type layer 311, a multiple quantum well layer 312, and a P-type layer 313 sequentially stacked on the substrate 40. The transparent conductive layer 32 and the first electrode 10 are located on the P-type layer 313, and the first electrode 10 is a P-electrode. The side of the epitaxial layer 31 away from the substrate 40 has a groove 31a exposing the N-type layer 311, and the second electrode 20 is located in the groove 31a and electrically connected to the N-type layer 311, and the second electrode 20 is an N-electrode.

[0075] The light-emitting diode may further include a passivation layer 42, which covers at least the transparent conductive layer 32, the sidewalls of the groove 31a, and the bottom of the groove 31a. The passivation layer 42 has through holes exposing the first electrode 10 and the second electrode 20 to facilitate the connection of the light-emitting diode with an external circuit structure.

[0076] like Figure 6 As shown, a distributed Bragg reflector layer 41 can also be provided on the side of the substrate 40 away from the light-emitting structure 30. By setting the distributed Bragg reflector layer 41 to reflect the light emitted by the light-emitting structure 30, the brightness of the light-emitting diode can be further improved.

[0077] Figure 8 This is a flowchart illustrating a method for fabricating a light-emitting diode (LED) according to an embodiment of this disclosure. This method is used to manufacture... Figures 2-7 The light-emitting diode shown. (As shown in the image) Figure 8 As shown, the preparation method includes:

[0078] S11: Provides a light-emitting structure 30.

[0079] S12: A first electrode 10 is formed on the surface of the light-emitting structure 30.

[0080] The first electrode 10 includes a pad 11 and an extension strip 12, one end of which is connected to the pad 11. The extension strip 12 includes multiple nano-conductive wires 122 and multiple conductive blocks 121, which are arranged at intervals and adjacent conductive blocks 121 are connected by nano-conductive wires 122.

[0081] By setting the nanoconductive wire 122 into a multi-layered structure, different materials can be used to make the inner conductive wire 1221, the first conductive coating layer 1222, and the second conductive coating layer 1223. This makes it easier to use suitable materials to make the nanoconductive wire 122 have good conductivity, sufficient structural strength, and be less prone to breakage. At the same time, it also has good resistance to corrosion and oxidation, further improving the reliability of the nanoconductive wire 122.

[0082] Figure 9 This is a flowchart illustrating a method for fabricating a light-emitting diode (LED) according to an embodiment of this disclosure. This method is used to manufacture... Figures 2-7 The light-emitting diode shown below. (The following is in conjunction with...) Figures 10-14 right Figure 9 The provided preparation method is described in detail, such as... Figure 9 As shown, the preparation method includes:

[0083] S21: Provides a light-emitting structure 30.

[0084] like Figure 10 As shown, the light-emitting structure 30 can be formed on the substrate 40. When fabricating a substrate-free light-emitting diode, the substrate can be removed after a certain stage of fabrication. This embodiment of the present disclosure takes the fabrication of a light-emitting diode with a substrate 40 as an example.

[0085] Optionally, the substrate 40 is a sapphire substrate, a silicon substrate, or a silicon carbide substrate. The substrate 40 can be a flat substrate or a patterned substrate.

[0086] As an example, in this embodiment of the disclosure, the substrate 40 is a sapphire substrate. Sapphire substrates are commonly used substrates, with mature technology and low cost. Specifically, it can be a patterned sapphire substrate or a flat sapphire substrate.

[0087] The light-emitting structure 30 includes an epitaxial layer 31 and a transparent conductive layer 32. The epitaxial layer 31 is epitaxially grown on a substrate 40 and may include an N-type layer 311, a multiple quantum well layer 312, and a P-type layer 313. The N-type layer 311, multiple quantum well layer 312, and P-type layer 313 are sequentially grown on the substrate 40. The growth method of the epitaxial layer 31 can refer to relevant technologies. For different light-emitting diodes, the structure included in the epitaxial layer 31 may also be different, for example, it may include, but is not limited to, a GaN buffer layer and a u-GaN layer located before the N-type layer 311. The N-type layer 311 and the P-type layer 313 can be single-layer structures or multi-layer structures. For example, the N-type layer 311 may include at least one n-GaN layer, and the P-type layer 313 may include a p-GaN layer and a p-InGaN layer. The materials of each layer in the epitaxial layer 31 may also differ, which will not be detailed here.

[0088] After the epitaxial layer 31 is formed, a groove 31a exposing the N-type layer 311 can also be formed by a patterning process.

[0089] Before fabricating the transparent conductive layer 32, a current blocking layer 33 can be formed on the epitaxial layer 31. The current blocking layer 33 is annular and located at the position of the pad 11 for setting the first electrode 10. The current blocking layer 33 can be made of an insulating material such as SiO2. The fabrication method of the current blocking layer 33 can also be the same as related technologies, which will not be described in detail here.

[0090] The transparent conductive layer 32 can be indium tin oxide (ITO), which can be fabricated by methods such as vapor deposition. Its structure can be referenced. Figure 7 As shown.

[0091] In this embodiment of the disclosure, the transparent conductive layer 32 has a plurality of laser annealing regions 321, a plurality of high tin composition regions 322 and a plurality of crystal orientation difference regions 323 in the annular region that contacts the pad 11 of the subsequently formed first electrode 10.

[0092] As an example, when forming the transparent conductive layer 32, the laser annealing region 321, the high tin composition region 322, and the crystal orientation difference region 323 can be formed in the following ways.

[0093] First, a first thin film is formed on the epitaxial layer 31. Then, a portion of the first thin film is removed, leaving a high-tin content region 322. Next, a second thin film is formed on the epitaxial layer 31 in the region outside the retained first thin film area. The tin content in the second thin film is lower than that in the first thin film. In this way, the retained portion of the first thin film and the second thin film form a transparent conductive layer 32.

[0094] During the deposition of the transparent conductive layer 32, the angle of the electron gun can be changed to alter the particle's trajectory, resulting in different crystal orientations in different regions of the formed transparent conductive layer 32.

[0095] After the coating is completed, laser annealing is used to form multiple dot-shaped laser annealing areas 321 on the transparent conductive layer 32.

[0096] S22: A partial structure of the first electrode 10 and a partial structure of the second electrode 20 are formed on the surface of the light-emitting structure 30.

[0097] The first electrode 10 includes a pad 11 and an extension strip 12. Both the first electrode 10 and the second electrode 20 are made of metal materials, and the first electrode 10 and the second electrode 20 can be fabricated simultaneously in the same coating process to save on process time.

[0098] Both the first electrode 10 and the second electrode 20 can be multilayer structures. The partial structure of the first electrode 10 and the partial structure of the second electrode 20 referred to here are partial layers forming a multilayer structure. For example, both the first electrode 10 and the second electrode 20 are structures in which a chromium layer 1211, a titanium layer 1212, a first gold layer 1213, and a second gold layer 1214 are stacked sequentially. Figures 11-13 Corresponding to Figure 2 BB section in. Figure 11 The diagram shows a partial structure of the formed first electrode 10. In step S22, a chromium layer 1211, a titanium layer 1212, and a first gold layer 1213 can be sequentially stacked on the transparent conductive layer 32. When fabricating using a patterning process, either a positive photoresist or a negative photoresist can be used.

[0099] The extension strip 12 includes multiple nano-conductive wires 122 and multiple conductive blocks 121. The conductive block 121 also includes a chromium layer 1211, a titanium layer 1212, a first gold layer 1213 and a second gold layer 1214 stacked sequentially. In step S22, when forming part of the structure of the first electrode 10, the chromium layer 1211, the titanium layer 1212 and the first gold layer 1213 of the conductive block 121 are also formed.

[0100] In the conductive block 121, multiple strip grooves 1213a can also be formed on the first gold layer 1213.

[0101] S23: Form nano-conductive wires 122 between adjacent conductive blocks 121.

[0102] like Figure 12 As shown, nano-conductive wires 122 are formed between adjacent conductive blocks 121. Exemplarily, a mixture of nano-conductive wires 122 can be prepared first, i.e., a mixture of nano-conductive wires 122 and a liquid, which will not dissolve or corrode the nano-conductive wires 122. The mixture is dripped between adjacent conductive blocks 121, using the liquid to carry the nano-conductive wires 122 between the conductive blocks 121, so that the two ends of the nano-conductive wires 122 are located in the grooves 1213a of the first gold layer 1213 of the adjacent conductive blocks 121. Due to its own fluidity and evaporation, the liquid naturally separates from the nano-conductive wires 122, thereby arranging the nano-conductive wires 122 between adjacent conductive blocks 121.

[0103] S24: Formation of the second gold layer 1214.

[0104] like Figure 13 As shown, after the second gold layer 1214 is fabricated, the first electrode 10 and the second electrode 20 are formed. In the extension strip 12, the nano-conductive wires 122 are tightly connected to the conductive block 121 under the action of the second gold layer 1214.

[0105] S25: Formation of passivation layer 42.

[0106] like Figure 14 As shown, the passivation layer 42 covers at least the transparent conductive layer 32, the sidewalls of the groove 31a, and the bottom of the groove 31a, and has a through hole exposing the first electrode 10 and the second electrode 20.

[0107] S26: Form a distributed Bragg reflector layer 41.

[0108] The structure after forming the distributed Bragg reflector layer 41 can be referred to Figure 6 As shown. Exemplarily, the substrate 40 can be thinned first from the side of the substrate 40 away from the light-emitting structure 30, for example, to 80 μm. Then, a distributed Bragg reflector layer 41 is formed on the side of the substrate 40 away from the light-emitting structure 30.

[0109] S27: Fragment.

[0110] In the fabrication of light-emitting diodes (LEDs), a single wafer is typically processed. After processing, multiple LEDs can be obtained by dicing the wafer.

[0111] During dicing, dicing can be performed using stealth cutting methods, such as employing a 1024 nm laser to dice the substrate 40 from the side away from the light-emitting structure 30. Using stealth cutting reduces the impact on the brightness of the LED. After dicing, the resulting LED can be tested.

[0112] In specific implementation, embodiments of this disclosure may use high-purity H2 and / or N2 as carrier gas, NH3 as N source, TEGa or TMGa as Ga source, TMIn as In source, SiH4 as n-type dopant, and TMAl as aluminum source.

[0113] The above description is merely an optional embodiment of this disclosure and is not intended to limit this disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the protection scope of this disclosure.

Claims

1. A light-emitting diode, characterized in that, It includes a light-emitting structure (30) and a first electrode (10), wherein the first electrode (10) is located on the surface of the light-emitting structure (30); The first electrode (10) includes a pad (11) and an extension strip (12). One end of the extension strip (12) is connected to the pad (11). The extension strip (12) includes multiple nano-conductive lines (122) and multiple conductive blocks (121). The multiple conductive blocks (121) are arranged at intervals. Each conductive block (121) includes a chromium layer (1211), a titanium layer (1212), a first gold layer (1213), and a second gold layer (1214) stacked sequentially. The nano-conductive lines (122) are located between the first gold layer (1213) and the second gold layer (1214). Adjacent conductive blocks (121) are connected through the nano-conductive lines (122).

2. The light-emitting diode according to claim 1, characterized in that, The nanoconductive wires (122) are located between adjacent conductive blocks (121) and are connected at both ends to the adjacent conductive blocks (121); or each nanoconductive wire (122) is connected to the plurality of conductive blocks (121).

3. The light-emitting diode according to claim 1, characterized in that, The nano-conductive wire (122) includes an inner conductive wire (1221), a first conductive coating layer (1222) and a second conductive coating layer (1223). The first conductive coating layer (1222) covers the inner conductive wire (1221), and the second conductive coating layer (1223) covers the first conductive coating layer (1222).

4. The light-emitting diode according to claim 3, characterized in that, The inner conductive wire (1221) is made of copper, the first conductive coating layer (1222) is made of copper-gold alloy, and the second conductive coating layer (1223) is made of gold.

5. The light-emitting diode according to claim 4, characterized in that, The inner conductive line (1221) has a diameter of 0.1μm to 0.3μm, the first conductive coating layer (1222) has a thickness of 0.01μm to 0.03μm, and the second conductive coating layer (1223) has a thickness of 0.01μm to 0.03μm.

6. The light-emitting diode according to claim 1, characterized in that, The surface of the first gold layer (1213) away from the titanium layer (1212) has a plurality of strip grooves (1213a), and the nanoconductive wires (122) are located in the plurality of strip grooves (1213a).

7. The light-emitting diode according to any one of claims 1 to 6, characterized in that, The light-emitting structure (30) includes an epitaxial layer (31) and a transparent conductive layer (32). The transparent conductive layer (32) is located on the surface of the epitaxial layer (31), the first electrode (10) is located on the transparent conductive layer (32), and the pad (11) is electrically in contact with the epitaxial layer (31) through a via. The annular region in contact between the transparent conductive layer (32) and the pad (11) includes at least one of the following: Multiple laser annealing zones (321); Multiple high-tin composition regions (322), wherein the tin composition within the high-tin composition regions (322) is higher than the tin composition outside the high-tin composition regions (322); Multiple crystal orientation difference regions (323), wherein the crystal orientation within the crystal orientation difference region (323) is different from the crystal orientation outside the crystal orientation difference region (323).

8. A method for fabricating a light-emitting diode, characterized in that, The method includes: Provide a light-emitting structure (30); A first electrode (10) is formed on the surface of the light-emitting structure (30). The first electrode (10) includes a pad (11) and an extension strip (12). One end of the extension strip (12) is connected to the pad (11). The extension strip (12) includes a plurality of nano-conductive lines (122) and a plurality of conductive blocks (121). The plurality of conductive blocks (121) are arranged at intervals. The conductive block (121) includes a chromium layer (1211), a titanium layer (1212), a first gold layer (1213), and a second gold layer (1214) stacked in sequence. The nano-conductive lines (122) are located between the first gold layer (1213) and the second gold layer (1214). Adjacent conductive blocks (121) are connected through the nano-conductive lines (122).

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