WO2023115855A1 - Circuit substrate, led display apparatus, and light-emitting element - Google Patents

Abstract

The present application provides a circuit substrate, an LED display apparatus, and a light-emitting element. According to the present application, heat absorption layers are arranged around or below the welding electrodes of the circuit substrate; the heat absorption layers can absorb laser energy and transmit the absorbed laser energy to the welding electrodes, so that the metal of the welding electrodes is heated and melted, and thus, an LED chip can be conveniently removed, and the subsequent maintenance or replacement of the LED chip is facilitated; after the LED chip is maintained or replaced, the heat absorption layers can also be irradiated by using laser, and the heat absorption layers absorb heat and transmit the heat to the welding electrodes, so that the welding electrodes are melted, and in this case, the electrodes of the LED chip are placed on the corresponding welding electrodes, and thus, the welding of the LED chip is achieved. The circuit substrate structure facilitates the maintenance of a Micro LED chip, and is simple in structure and low in manufacturing cost. In addition, the position relationship between the heat absorption layers and the welding electrodes in the circuit substrate, and the shape structures of the heat absorption layers are variously changed and can be adjusted according to actual requirements, and thus, the design of the circuit substrate is flexible and diversified.

Description

Circuit board, LED display device and light emitting element technical field

The present application relates to the technical field of semiconductor devices, in particular to a circuit substrate, an LED display device and a light emitting element.

Background technique

LED is widely valued for its high luminous efficiency, long service life, safety, reliability, environmental protection and energy saving. Among them, micro LED is usually used in display screens. The biggest difference between Micro LED display and LCD/OLED display is the combination of LCD and OLED light emitting devices and TFT backplane. LCD is a combination of backlight and liquid crystal switch, OLED is an organic light-emitting material attached to the TFT backplane, and voltage/current is given through the TFT backplane electrodes. The Micro LED display is to electrically connect the Micro LED chip to the TFT backplane electrode through different welding methods, and then give the Micro LED chip a voltage/current through the TFT backplane to emit light.

The biggest difficulty of Micro LED display is that Micro LED chips need to be fabricated on another carrier, and then transferred to the TFT backplane in large quantities through mass transfer. This is very different from the OLED manufacturing process. OLED is to directly manufacture luminescent materials on the TFT backplane. The gap between the two processes makes the combination of the Micro LED light-emitting device and the TFT backplane directly affect the yield rate of the display screen. LED repair process is therefore particularly important.

Traditional LED chips are electrically connected by soldering the LED chips to the PCB/TFT backplane with solder paste. Nowadays, in order to quickly repair LED chips, the technology of laser removal of LED chips has been developed one by one. It uses laser energy to excite the organic materials in the solder paste, so that the temperature of the solder paste will rise after absorbing the laser energy, so that the solder paste will melt. Pick up the LED chip. Afterwards, using the same laser process technology, the LED chips are re-soldered to the PCB/TFT backplane. However, the Micro LED chip cannot be soldered to the substrate through solder paste, so the above-mentioned traditional process cannot be used.

technical problem

Therefore, there is an urgent need for a technology that can effectively remove micro LED chips.

technical solution

In order to overcome at least some of the defects and deficiencies in the related art, the present application provides a circuit substrate for welding LED chips, an LED display device and a light emitting element. A heat absorbing layer is arranged under or around the welding electrodes of the circuit substrate, and the heat absorbing layer can effectively absorb laser heat, heat the welding electrodes after absorbing heat, and melt the welding electrodes, so that the LED chip can be removed conveniently.

On the one hand, a circuit substrate provided by an embodiment of the present application includes, for example: an insulating substrate; a wiring layer disposed on the insulating substrate, the wiring layer including a die-bonding area, and the die-bonding area has a function for soldering LED chips. The welding electrode; the heat absorption layer, which is in contact with the welding electrode, is used to conduct the absorbed heat to the welding electrode.

In one embodiment of the present application, the heat absorbing layer is located below the welding electrode, and the edge of the heat absorbing layer exceeds the edge of the welding electrode.

In one embodiment of the present application, the heat absorbing layer is located under the entire welding electrode, and a through hole is arranged in the heat absorbing layer, and the welding electrode communicates with the circuit layer through the through hole .

In one embodiment of the present application, the heat absorbing layer is located below the edge region of the welding electrode.

In one embodiment of the present application, the heat absorbing layer is arranged on the periphery of the welding electrode.

In one embodiment of the present application, the heat absorbing layer is formed into a ring structure, or a ring structure with a hollow structure.

In one embodiment of the present application, the heat absorbing layer is formed on the sides of the welding electrodes in the same die-bonding area away from each other; the heat absorbing layer forms a strip-like structure.

In one embodiment of the present application, the heat absorbing layer forms a strip-shaped structure with a hollow structure.

In one embodiment of the present application, the circuit substrate further includes an insulating layer, the insulating layer is disposed on a side of the circuit layer away from the insulating substrate, and exposes the welding electrodes.

In one embodiment of the present application, the thickness of the heat absorbing layer ranges from 0.5 μm to 5 μm.

In one embodiment of the present application, the welding electrodes include a first welding electrode and a second welding electrode as a repair pad; the heat absorbing layer includes a first heat absorbing layer and a second heat absorbing layer, and the first heat absorbing layer A heat absorbing layer and the second heat absorbing layer are respectively in contact with the first welding electrode and the second welding electrode, and the first heat absorbing layer and the second heat absorbing layer are used to absorb laser, and conduct the absorbed heat to the welding electrode.

In one embodiment of the present application, the first welding electrode and the second welding electrode are arranged side by side with a distance from each other; the first heat absorbing layer is arranged around the first welding electrode, and the second welding electrode The heat absorbing layer is arranged around the second welding electrode, and the first heat absorbing layer and the second heat absorbing layer are arranged side by side; or the first heat absorbing layer is arranged on the side of the first welding electrode Below and around, the second heat absorbing layer is arranged below and around the second welding electrode, and the first heat absorbing layer and the second heat absorbing layer are arranged side by side.

In one embodiment of the present application, along the direction from the insulating substrate to the circuit layer, the second heat absorbing layer, the second welding electrode, the first heat absorbing layer and the first The welding electrodes are stacked one on top of the other.

In one embodiment of the present application, the second heat absorbing layer, the second welding electrode, the first heat absorbing layer and the first welding electrode are sequentially stacked to form a first stack and a second stack spaced apart from each other, The opposite sides of the first stack and the second stack are flush side walls.

In one embodiment of the present application, the melting point of the first welding electrode is lower than the melting point of the second welding electrode.

On the other hand, an LED display device provided by an embodiment of the present application includes, for example: the circuit substrate according to any one of claims 1-15; and an LED chip soldered on the circuit substrate.

On the other hand, a light-emitting element provided by an embodiment of the present application includes: a light-emitting structure, the light-emitting structure has a light-emitting surface; an electrode structure is arranged on the back of the light-emitting structure away from the light-emitting surface to form a an electrical connection; a heat absorbing layer formed on the back of the light emitting structure and surrounding the electrode structure, the heat absorbing layer absorbing the heat of the laser light and conducting the absorbed heat to the electrode structure.

In one embodiment of the present application, the heat-absorbing layer includes at least one heat-absorbing layer, and when the heat-absorbing layer includes two or more heat-absorbing layers, multiple layers of the heat-absorbing layers are stacked in sequence on the back of the light-emitting structure.

In one embodiment of the present application, the heat absorbing layer includes a first heat absorbing layer and a second heat absorbing layer, and the first heat absorbing layer and the second heat absorbing layer are used to absorb laser light of different wavelengths, The electrode structure includes a first electrode and a second electrode, the first heat absorbing layer is formed on the side of the back where the first electrode is located, and the second heat absorbing layer is formed on the second electrode It is located on one side of the back side, and the first heat absorbing layer and the second heat absorbing layer form a continuous structure.

In an embodiment of the present application, the first heat absorbing layer is further formed on the first side wall of the light emitting structure on the side of the first electrode, and the second heat absorbing layer is further formed on the first side wall of the light emitting structure. On the second side wall of the light emitting structure on the side of the two electrodes.

Beneficial effect

In summary, the above technical solution of the present application may have one or more of the following beneficial effects:

1. By setting a heat absorbing layer around or below the welding electrode of the circuit board, the heat absorbing layer can absorb laser energy and transfer the absorbed laser energy to the welding electrode, so that the metal of the welding electrode is heated and melted, so that it can be easily removed Removing the LED chip facilitates subsequent maintenance or replacement of the LED chip. After maintenance or replacement of the LED chip, laser radiation can also be used to irradiate the heat absorbing layer. The heat absorbing layer absorbs heat and conducts it to the welding electrode to melt the welding electrode. At this time, the electrode of the LED chip is placed on the corresponding welding electrode. Realize the welding of LED chips. The above circuit substrate structure is convenient for Micro The LED chip is maintained, and the structure is simple and the manufacturing cost is low. In addition, 2. The positional relationship and shape structure of the heat absorbing layer in the embodiment of the application in the circuit substrate and the welding electrodes can have various deformations, and can be adjusted according to actual needs, and the design of the circuit substrate is flexible and diverse.

3. By setting a heat absorbing layer around the welding electrode of the circuit board, the heat absorbing layer includes a first heat absorbing layer and a second heat absorbing layer, and the first heat absorbing layer and the second heat absorbing layer are respectively connected to the first heat absorbing layer of the welding electrode. The welding electrode is in contact with the second welding electrode. The first heat absorbing layer and the second heat absorbing layer are configured to absorb laser light of different wavelengths, and transfer the energy of the absorbed laser light to the welding electrode, so that the metal of the welding electrode is heated and melted. When welding and removing the main light-emitting components, such as LED chips, the first heat-absorbing layer is irradiated with the laser of the first wavelength so that the metal of the first welding electrode is heated and melted, and the welding and removal of the LED chips are completed; When chipping, the laser of the second wavelength is used to irradiate the second heat absorbing layer so that the metal of the second welding electrode is heated and melted, and the welding of the LED chip is completed. The arrangement of the first heat absorbing layer and the second heat absorbing layer can accurately heat the first welding electrode or the second welding electrode, and avoids mutual influence between the first welding electrode and the second welding electrode.

4. The melting point of the first welding electrode is lower than the melting point of the second welding electrode, therefore, the integrity of the second welding electrode will not be damaged when welding the main light-emitting element, which is beneficial to ensure the subsequent welding on the second welding electrode to repair the luminescence component yield.

5. The positional relationship between the heat absorbing layer and the welding electrode in the circuit substrate and the shape structure can have various deformations, for example, the first heat absorbing layer and the second heat absorbing layer are arranged side by side with the first welding electrode and the second welding electrode, Alternatively, in a direction away from the circuit substrate, the second heat absorbing layer, the second welding electrode, the first heat absorbing layer and the first welding electrode are stacked in sequence. The various settings of the above heat absorbing layer and welding electrodes can be adjusted according to actual needs, and the design of the circuit substrate is flexible and diverse. When the second heat-absorbing layer, the second welding electrode, the first heat-absorbing layer and the first welding electrode overlap, the first welding electrode and the first heat-absorbing layer shall select materials that are easy to remove to ensure that the first welding electrode and the first heat-absorbing layer The removal of the heat absorbing layer will not affect the integrity of the second heat absorbing layer and the second welding electrode. At the same time, the stacked structure is beneficial to reduce the size of the crystal-bonding region, and further facilitates the wiring arrangement of the circuit layer.

6. The circuit substrate structure provided by the embodiment of the present application is convenient for maintenance of the Micro LED chip, and the structure is simple and the manufacturing cost is low.

7. A heat absorbing layer is formed on the back of the light emitting structure of the light emitting element. The heat absorbing layer can transfer the heat of the absorbed laser light to the electrode structure, so that the electrode structure is melted by heat and then welded to the circuit substrate when cooling. The arrangement of the heat absorbing layer makes it easier to realize the heating of the electrode structure of the light emitting structure, and different wavelengths of laser light can be used to irradiate the heat absorbing material to make it absorb different heat, thus making the light emitting element suitable for different welding processes, for example, as the main A welding process of the light-emitting element and a repair welding process as a repair of the light-emitting element.

Description of drawings

The specific implementation manners of the present application will be described in detail below in conjunction with the accompanying drawings.

FIG. 1 is a schematic structural diagram of a circuit substrate in the related art.

FIG. 2 is a schematic structural diagram of a circuit substrate provided in Embodiment 1 of the present application.

FIG. 3 is a schematic top view of the circuit substrate shown in FIG. 2 .

FIG. 4 is a schematic structural diagram of a circuit substrate provided in Embodiment 2 of the present application.

FIG. 5 is a schematic top view of the circuit substrate shown in FIG. 4 .

FIG. 6 is a schematic structural diagram of a circuit substrate provided in Embodiment 3 of the present application.

FIG. 7 is a schematic top view of the circuit substrate shown in FIG. 6 .

FIG. 8 is a schematic structural diagram of a circuit substrate provided in Embodiment 4 of the present application.

FIG. 9 is a schematic top view of the circuit substrate shown in FIG. 8 .

FIG. 10 is a schematic structural diagram of a circuit substrate provided in Embodiment 5 of the present application.

FIG. 11 is a schematic top view of the circuit substrate shown in FIG. 10 .

FIG. 12 is a schematic structural diagram of an LED display device provided in Embodiment 6 of the present application.

FIG. 13 is a schematic structural diagram of a circuit substrate provided in Embodiment 7 of the present application.

FIG. 14 is a schematic structural diagram of a circuit substrate in an alternative embodiment of the seventh embodiment.

FIG. 15 is a schematic top view of the circuit substrate shown in FIG. 13 and FIG. 14 .

FIG. 16 is a schematic structural diagram of a circuit substrate provided in Embodiment 8 of the present application.

FIG. 17 is a schematic top view of the circuit substrate shown in FIG. 16 .

FIG. 18 is a schematic structural diagram of an LED display device provided in Embodiment 9 of the present application.

Fig. 19 is a cross-sectional view along line L1-L1 in Fig. 18 .

Fig. 20 is a cross-sectional view along line L1-L1 in Fig. 18 in an alternative embodiment.

FIG. 21 is a schematic structural diagram of a light emitting element provided in Embodiment 10 of the present application.

FIG. 22 is a schematic bottom view of the light emitting element shown in FIG. 21 .

Fig. 23 is a schematic structural diagram of a light emitting element provided in Embodiment 11 of the present application.

FIG. 24 is a schematic structural diagram of a light emitting element provided in Embodiment 12 of the present application.

FIG. 25 is a schematic structural diagram of a light emitting element provided in Embodiment 13 of the present application.

Component designation description

11	PCB backplane	121	first stack
12	welding electrode	122	second stack
13	LED chip	200	LED display device
14	Solder paste	201	LED chips
100	circuit board	2011	first chip
110	insulating substrate	2012	second chip
101	line layer	300	Light emitting element
1011	Die bonding area	301	light emitting structure
102	Insulation	3011	first semiconductor layer
103	welding electrode	3012	second semiconductor layer
1031	first welding electrode	3013	active layer
1031-1	first positive welding electrode	302	heat absorbing layer
1031-2	first negative welding electrode	3021	third heat absorbing layer
1032	Second welding electrode	3022	The fourth heat absorbing layer
1032-1	Second positive welding electrode	303	Insulation
1032-2	Second negative welding electrode	304	electrode structure
1033	edge area	3041	first electrode
1034	middle area	3042	second electrode
104	heat absorbing layer	305	through hole
1041	first heat absorbing layer	310	light emitting surface
1042	second heat absorbing layer	320	back
105	through hole

the

BEST MODE FOR CARRYING OUT THE INVENTION

Type the paragraph describing the best mode for carrying out the invention here.

Embodiments of the present invention

In order to make the above-mentioned purpose, features and advantages of the present application more obvious and understandable, the specific implementation manners of the present application will be described in detail below in conjunction with the accompanying drawings.

In order to enable those of ordinary skill in the art to better understand the technical solutions of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described implementation Examples are only some of the embodiments of the present application, not all of them. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the scope of protection of this application.

It should be noted that the directional terms mentioned in the embodiments of the present utility model, such as "up", "down", "front", "back", "left", "right", "inside", "outside", " Side", etc., are only referring to the directions of the attached drawings. Therefore, the used directional terms are used to illustrate and understand the present invention, but not to limit the present invention. For understanding and ease of description, the size and thickness of each component shown in the drawings are arbitrarily shown, but the present invention is not limited thereto.

It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present. Also, in the specification, unless it is clearly described to the contrary, the word "comprising" will be understood as meaning including the stated components but not excluding any other components. In addition, in the specification, "on" means located above or below the target component, and does not mean necessarily located on top based on gravity.

As shown in Figure 1, taking the PCB backplane as an example, the traditional LED chip 013 is welded to the welding electrode 012 of the PCB backplane 011 through solder paste 014, thereby realizing the fixation and electrical performance of the LED chip 013 and the PCB backplane 011. connect. When the LED chip is damaged or the performance is poor, in order to quickly repair the LED chip, the laser energy is used to excite the organic material in the solder paste 014, so that the temperature of the solder paste will rise after absorbing the laser energy, so that the solder paste will melt, and then the LED chip will be picked up. Afterwards, using the same laser process technology, the LED chips are re-soldered to the PCB/TFT backplane. However, the Micro LED chip cannot be soldered to the substrate through solder paste, so the above-mentioned traditional process cannot be used.

[Embodiment 1] In view of the above-mentioned defects in the related art, this embodiment provides a circuit substrate 100 for welding LED chips, and the LED chips are preferably micro LED chips with a size smaller than 75 μm. As shown in FIG. 2 , the circuit substrate 100 of this embodiment includes, for example, an insulating substrate 110 and a circuit layer 101 disposed on the insulating substrate 110. The circuit layer 101 includes a die-bonding area 1011. welding electrode 103 . The welding electrodes 103 realize the fixing of the LED chip on the circuit substrate 100 and the electrical connection with the circuit layer 101 . Likewise, as shown in FIG. 2 , the circuit substrate 100 further includes, for example, a heat absorbing layer 104 , which is in contact with the welding electrode 103 for conducting absorbed heat to the welding electrode 103 .

As shown in FIG. 3 , referring to FIG. 2 at the same time, in this embodiment, the heat absorbing layer 104 is located below the welding electrode 103 , and the edge of the heat absorbing layer 104 exceeds the edge of the welding electrode 103 . That is, as shown in FIG. 3 , the planar area of the heat absorbing layer 104 is larger than that of the welding electrode 103 . In an optional embodiment, the thickness of the heat absorbing layer ranges from 0.5 μm to 5 μm. Also referring to FIG. 3 , when the heat absorbing layer 104 is located below the welding electrode 103, in order to realize the communication between the welding electrode 103 and the circuit layer 101, a plurality of through holes 105 are formed in the heat absorbing layer 104, and the through holes 105 run through the heat absorbing layer 104. layer 104 and exposes the circuit layer 101 . Soldering electrodes 103 are simultaneously formed in the through holes 105 to realize communication with the circuit layer 101 . The through hole 1105 not only realizes the connection between the welding electrode 103 and the circuit layer 101 , but also ensures a certain contact area between the welding electrode 103 and the circuit layer 101 , ensuring the stability of the welding electrode 103 .

Also referring to FIG. 2 , the circuit substrate 100 also includes an insulating layer 102 , which is formed above the circuit layer 101 , that is, disposed on the side of the circuit layer 101 away from the insulating substrate 110 , to protect the circuit layer 101 . At the same time, the insulating layer 102 exposes the welding electrode 103 in the area where the welding electrode 103 is located. In an optional embodiment, the above-mentioned circuit substrate 100 may be a PCB board (printed circuit board, printed circuit board), TFT (thin film transistor, thin film transistor) substrate. When the above-mentioned circuit substrate 100 is a PCB board, it may be a single-layer substrate or a multi-layer composite substrate.

In an optional embodiment, the heat absorbing layer 104 is a laser absorbing material, which may be a laser absorbing material with different wavelengths. For example, it may be a laser-absorbing resin to which a laser-absorbing agent is added, which contributes to the absorption of laser light and converts the absorbed laser light into heat.

As mentioned above, the heat absorbing layer 104 has a part exposed outside the welding electrode 103, therefore, when it is necessary to solder or remove the LED chip, the laser only needs to be irradiated to the heat absorbing layer 104 exposed outside the welding electrode 103, at this time The heat absorbing layer 104 absorbs the energy of the laser to generate heat, and then conducts the heat to the welding electrode 103, so that the metal of the welding electrode 103 is heated and melted, which is convenient for welding or removing the LED chip.

[Embodiment 2] This embodiment also provides a circuit substrate 100 for welding LED chips, and the LED chips are preferably micro LED chips with a size smaller than 75 μm. As shown in FIG. 4 , the circuit substrate 100 of this embodiment includes, for example, an insulating substrate 110 and a circuit layer 101 disposed on the insulating substrate 110. The circuit layer 101 includes a die-bonding area 1011. welding electrode 103 . The welding electrodes 103 realize the fixing of the LED chip on the circuit substrate 100 and the electrical connection with the circuit layer. As shown in FIG. 4 , the circuit substrate 100 also includes a heat absorbing layer 104 , which is in contact with the welding electrode 103 and is used for conducting absorbed heat to the welding electrode 103 .

The difference between the heat absorbing layer of this embodiment and Embodiment 1 is that: as shown in FIG. The above-mentioned heat absorbing layer is not formed below, that is, as shown in FIG. Preferably, the heat absorbing layer 104 can also be formed as a ring structure with a hollow structure, for example, it can have a rectangular hollow, a circular hollow or any other hollow pattern. The heat absorbing layer 104 of the present application is formed into a ring structure located below the welding electrode 103, thereby increasing the contact area between the welding electrode and the circuit layer, and increasing the stability of the welding electrode.

[Embodiment 3] This embodiment also provides a circuit substrate 100 for welding LED chips, and the LED chips are preferably micro LED chips with a size smaller than 75 μm. As shown in FIG. 6 , the circuit substrate 100 of this embodiment includes an insulating substrate 110 and a circuit layer 101 arranged on the insulating substrate 110. The circuit layer 101 includes a crystal-bonding area 1011, and the crystal-bonding area 1011 has a welding area for welding LED chips. electrode 103 . The welding electrodes 103 realize the fixing of the LED chip on the circuit substrate 100 and the electrical connection with the circuit layer. As shown in FIG. 6 , the circuit substrate 100 also includes a heat absorbing layer 104 , which is in contact with the welding electrode 103 and is used to conduct absorbed heat to the welding electrode 103 .

The heat absorption layer 104 of this embodiment is different from the first and second embodiments in that: in this embodiment, the heat absorption layer 104 is formed below one side of the welding electrode 103 . In the same die-bonding area 1011 , the heat absorbing layer 104 is preferably formed on the side of the same die-bonding area 1011 where the two welding electrodes are away from each other, as shown in FIGS. 6 and 7 . Likewise, the edge of the heat absorbing layer 104 also exceeds the edge of the welding electrode 103 , forming a strip-shaped structure protruding from the welding electrode 103 . At the same time, the heat absorbing layer of the strip structure may also be formed with a hollow structure, for example, may have a rectangular hollow, circular hollow or any other hollow pattern. The above-mentioned heat absorbing layer has a simple structure and does not affect the connection stability between the welding electrode and the circuit layer. At the same time, it can fully absorb the laser energy and convert it into heat, and conduct the heat to the metal of the welding electrode, so that the metal is heated and melted, which is convenient for welding or removing LED chips. .

[Embodiment 4] This embodiment also provides an example of a circuit substrate 100 for welding LED chips, and the LED chip is preferably a micro LED chip with a size smaller than 75 μm. As shown in FIG. 8 , the circuit substrate 100 of this embodiment includes an insulating substrate 110 and a circuit layer 101 disposed on the insulating substrate 110. The circuit layer 101 includes a crystal-bonding area 1011, and the crystal-bonding area 1011 has a welding area for welding LED chips. electrode 103 . The welding electrodes 103 realize the fixing of the LED chip on the circuit substrate 100 and the electrical connection with the circuit layer. As shown in FIG. 8 , the circuit substrate 100 also includes a heat absorbing layer 104 , which is in contact with the welding electrode 103 and is used to conduct absorbed heat to the welding electrode 103 .

The difference between the heat absorbing layer in this embodiment and Embodiments 1 to 3 is that in this embodiment, the heat absorbing layer 104 is formed on the periphery of the welding electrode 103, that is, it is only formed on the outside of the welding electrode and contacts the welding electrode. However, the above-mentioned heat absorbing layer is not formed under the welding electrodes. As shown in FIG. 8 and FIG. 9 , the heat absorbing layer 104 is formed around the two welding electrodes 103 in the same die-bonding area 1011 , forming a ring structure around the two welding electrodes. The annular structure may also be formed as an annular structure with a hollow pattern, for example, may have a rectangular hollow, a circular hollow or any other hollow pattern. Referring to Fig. 8, in this embodiment, the upper surface of the above-mentioned heat absorbing layer 104 is not higher than the upper surface of the welding electrode 103, thereby ensuring that the heat absorbing layer will not pollute or cover the welding electrode, and ensure the effective welding area of the welding electrode, Easy to solder LED chips.

[Embodiment 5] This embodiment also provides a circuit substrate 100 for welding LED chips, and the LED chips are preferably micro LED chips with a size smaller than 75 μm. As shown in FIG. 10 , the circuit substrate 100 of this embodiment includes an insulating substrate 110 and a circuit layer 101 arranged on the insulating substrate 110. The circuit layer 101 includes a crystal-bonding area 1011, and the crystal-bonding area 1011 has a welding area for welding LED chips. electrode 103 . The welding electrodes 103 realize the fixing of the LED chip on the circuit substrate 100 and the electrical connection with the circuit layer. As shown in FIG. 10 , the circuit substrate 100 also includes a heat absorbing layer 104 , which is in contact with the welding electrode 103 for conducting the absorbed heat to the welding electrode 103 .

The heat absorption layer of this embodiment is different from Embodiments 1 to 4 in that: in this embodiment, as shown in FIG. 10 , the heat absorption layer 104 is only formed on the periphery of one side of the welding electrode 103, touch. As shown in FIGS. 10 and 11 , in an alternative embodiment, the heat absorbing layer 104 is formed on the side of the two welding electrodes of the same die-bonding region 1011 away from each other. The heat absorbing layer 104 is formed as a strip structure on one side of the welding electrode 103 , and optionally, the strip structure may also have a hollow pattern. Preferably, both ends of the heat absorbing layer 104 protrude from the edge of the welding electrode 103, so as to receive laser radiation and absorb energy.

[Embodiment 6] As shown in FIG. 12 , this embodiment provides an LED display device 200 . The LED display device 200 of this embodiment includes, for example, a circuit substrate 100 and a plurality of LED chips 201 . Taking a micro LED chip with a size smaller than 75 μm as an example, the LED chip 201 includes, for example, a light-emitting epitaxial layer (shown in the figure) and an electrode 2013 . The light-emitting epitaxial layer includes, for example, a first semiconductor layer (such as an N-type GaN layer), an active layer above the first semiconductor layer (such as an InsGa1-sN/AlGaN multiple quantum well layer), and a second semiconductor layer above the active layer. (eg P-type GaN layer). The min LED chip has a small size and no substrate, so when it is placed on the circuit substrate, the chip electrode 2013 is welded to the welding electrode 103 of the circuit substrate 100 by metal welding to realize the electrical connection between the LED chip and the circuit substrate.

Figure 12 only exemplarily shows a single LED chip welded on the circuit substrate 100, it can be understood that there may be several LED chips on the circuit substrate, and several LED chips are arranged in an array on the circuit substrate, and the LED chips 201 may be Various suitable or required forms are arranged on the circuit substrate 100 . The circuit substrate is any one of the circuit substrates provided in Embodiment 1 to Embodiment 5. Since the heat absorbing layer 104 is arranged under the welding electrode 103 of the circuit substrate 100, when the LED chip 201 is welded, the laser is irradiated to the heat absorbing layer 104, and the heat absorbing layer 104 absorbs the heat of the laser energy conversion layer and transfers the heat to the welding electrode 103 , so that the welding electrode 103 is heated and melted, the electrode 2013 of the LED chip 201 is placed on the welding electrode 103, and the welding electrode 103 is cooled and solidified to realize the fixed welding of the LED chip 201.

When an LED chip in the LED display device 200 is damaged or malfunctions, after the damaged or malfunctioning LED chip is found, laser irradiation is used to weld the heat absorbing layer around the welding electrode of the LED chip, and the heat absorbing layer absorbs the laser energy and converts it into heat, and conduct the heat to the welding electrode, so that the welding electrode melts, so that the LED chip can be removed quickly. After the LED chip is repaired or replaced, the welding electrode is melted in the same manner, and then the LED chip is welded to the welding electrode to realize the repair or replacement of the LED chip.

[Embodiment 7] This embodiment provides a circuit substrate 100 for welding LED chips, and the LED chips are preferably micro LED chips with a size smaller than 75 μm. As shown in FIG. 13 , the circuit substrate 100 of this embodiment includes an insulating substrate 110 and a circuit layer 101 arranged on the insulating substrate 110. The circuit layer 101 includes a crystal-bonding area 1011, and the crystal-bonding area 1011 has a welding area for welding LED chips. electrode 103 . The welding electrodes 103 realize the fixing of the LED chip on the circuit substrate 100 and the electrical connection with the circuit layer 101 . Referring to FIG. 13 and FIG. 15 , the circuit substrate 100 further includes a heat absorbing layer 104 in contact with the welding electrode 103 for conducting absorbed heat to the welding electrode 103 .

As shown in Figure 13, the welding electrode 103 includes a first welding electrode 1031 and a second welding electrode 1032, the first welding electrode 1031 is used to weld the LED chip as the main light emitting element, and the second welding electrode 1032 is used as a repair electrode for Soldering and replacing the LED chip for repair of the main light-emitting element. Preferably, the melting point of the first welding electrode 1031 is lower than the melting point of the second welding electrode 1032, thereby ensuring that when the first welding electrode 1031 is heated and melted, the second welding electrode 1032 will not be heated and melted or softened to ensure that the second welding electrode The integrity of the electrode 1032. Specifically, as shown in FIG. 13 , the first welding electrodes 1031 and the second welding electrodes 1032 are arranged side by side at intervals from each other. As shown in Figure 13, the first welding electrode 1031 includes a first positive welding electrode 1031-1 and a first negative welding electrode 1031-2 for welding the positive and negative electrodes of the LED chip, and the second welding electrode 1032 includes a welding electrode for welding the positive and negative electrodes of the LED chip. The second positive welding electrode 1032-1 and the second negative welding electrode 1031-2, therefore, in an alternative embodiment, the first positive welding electrode 1031-1 and the second positive welding electrode 1032-1 are adjacent, and the first negative welding electrode The welding electrode 1031-2 is adjacent to the second negative welding electrode 1031-2, wherein the first positive welding electrode 1031-1 and the second positive welding electrode 1032-1 are welded to the first negative welding electrode 1031-2 and the second negative welding electrode 1031-2. The electrodes 1031-2 are arranged insulated from each other, thus forming a side-by-side structure as shown in FIG. 13 .

Also as shown in FIG. 13 , in this embodiment, the heat absorbing layer 104 is located around the welding electrode 103 . Specifically, the heat absorbing layer 104 is a laser absorbing material, including a first heat absorbing layer 1041 and a second heat absorbing layer 1042, and the first heat absorbing layer 1041 and the second heat absorbing layer 1042 are configured to absorb laser light of different wavelengths, thereby Produce unequal amounts of energy. In an optional embodiment, the above-mentioned heat absorbing layer 104 may be a laser absorbing resin, in which a laser absorber is added, and the laser absorber helps to absorb laser light and convert the absorbed laser light into heat.

As shown in FIGS. 13 and 15 , the first heat absorbing layer 1041 is arranged around the first welding electrode 1031 to surround the first welding electrode 1031 , and the second heat absorbing layer 1042 is arranged around the second welding electrode 1032 to surround the second welding electrode 1031 . Electrode 1032. Specifically, the first heat absorbing layer 1041 is respectively arranged around the first positive welding electrode 1031-1 and the first negative welding electrode 1031-2, and the second heat absorbing layer 1042 is respectively arranged around the second positive welding electrode 1032-1 and the first negative welding electrode 1032-1. Around two negative welding electrodes 1031-2. Optionally, the first heat absorbing layer 1041 and the second heat absorbing layer 1042 form a continuous structure around the first welding electrode 1031 and the second welding electrode 1032 . As shown in FIG. 15 , the projection of the heat absorbing layer 104 on the insulating substrate 110 is located around the projection of the welding electrode 103 on the insulating substrate 110 and closely adjacent to the welding electrode 103 to transfer heat to the welding electrode 103 .

In an optional embodiment, the heat absorbing layer 104 is located below and around the welding electrode 103. At this time, in order to realize the electrical connection between the welding electrode 103 and the circuit layer 102, a plurality of through holes can be formed in the heat absorbing layer 104. The vias are filled with conductive metal. As shown in FIG. 14 , the first heat absorption layer 1041 is disposed under and around the first welding electrode 1031 , and the second heat absorption layer 1042 is disposed under and around the second welding electrode 1032 . Specifically, the first heat absorbing layer 1041 is respectively arranged under and around the first positive welding electrode 1031-1 and the first negative welding electrode 1031-2, and the second heat absorbing layer 1042 is respectively arranged on the second positive welding electrode 1032-1. and below and around the second negative welding electrode 1031-2. Optionally, the first heat absorbing layer 1041 and the second heat absorbing layer 1042 form a continuous structure around the first welding electrode 1031 and the second welding electrode 1032 . At this time, as shown in FIG. 15 , the projected area of the heat absorbing layer 104 on the insulating substrate 110 is larger than the projected area of the welding electrode 103 on the insulating substrate 110 .

When it is necessary to weld or remove the LED chip at the first welding electrode 1031, it is only necessary to irradiate the heat absorbing layer 104 exposed outside the welding electrode 103 with the laser of the first wavelength. The heat absorbing layer 1041 absorbs the laser energy of the first wavelength and generates heat, and then conducts the heat to the first welding electrode 1031 , so that the metal of the first welding electrode 1031 is heated and melted to realize welding or removal of the LED chip. When it is necessary to weld the LED chip at the second welding electrode 1032, it is only necessary to irradiate the heat absorbing layer 104 exposed outside the welding electrode 103 with the laser of the second wavelength. At this time, the second heat absorbing layer in the heat absorbing layer 104 1042 absorbs the laser energy of the second wavelength and generates heat, and then conducts the heat to the second welding electrode 1032, so that the metal of the second welding electrode 1032 is heated and melted to realize the welding of the LED chip. It can be seen that the arrangement of the heat absorbing layer 104 in this embodiment can respectively heat the first welding electrode 1031 or the second welding electrode 1032 according to needs, which is convenient for welding and repairing of LED chips.

In an optional embodiment, the thickness of the heat absorbing layer 104 is smaller than the height of the welding electrode 103, for example, the thickness of the heat absorbing layer 104 is between 0.5 μm and 5 μm, while the thickness of the welding electrode 103 is between 20 μm and 30 μm. Such setting makes the welding electrode 103 higher than the heat absorbing layer 104, which is convenient for the subsequent heat absorbing layer 104 to transfer energy to the welding electrode 103, and will not affect the exposed and melted welding electrode 103, so that the metal of the welding electrode 103 is melted and welded to the LED chip .

As shown in FIG. 13 and FIG. 14 , the circuit substrate 100 further includes an insulating layer 102 formed on the circuit layer 101 to protect the circuit layer 101 . At the same time, the insulating layer 102 exposes the welding electrode 103 and the heat absorbing layer 104 in the area where the welding electrode 103 is located. In an optional embodiment, the above-mentioned circuit substrate 100 may be a PCB board (printed circuit board, printed circuit board), TFT (thin film transistor, thin film transistor) substrate. When the above-mentioned circuit substrate 100 is a PCB board, it may be a single-layer substrate or a multi-layer composite substrate.

[Embodiment 8] This embodiment also provides a circuit substrate 100 for welding LED chips, and the LED chips are preferably micro LED chips with a size smaller than 75 μm. As shown in FIG. 16 , the circuit substrate 100 of this embodiment includes an insulating substrate 110 and a circuit layer 101 disposed on the insulating substrate 110. The circuit layer 101 includes a crystal-bonding area 1011, and the crystal-bonding area 1011 has a welding area for welding LED chips. electrode 103 . The welding electrodes 103 realize the fixing of the LED chip on the circuit substrate 100 and the electrical connection with the circuit layer 101 . As shown in FIG. 16 , the circuit substrate 100 also includes a heat absorbing layer 104 , which is in contact with the welding electrode 103 and used for conducting absorbed heat to the welding electrode 103 .

The difference between this embodiment and Embodiment 7 is that the heat absorbing layer 104 and the welding electrode 103 are arranged differently. Specifically: as shown in FIG. 16 , in this embodiment, in the direction away from the circuit substrate 100, the The second heat absorbing layer 1042 , the second welding electrode 1032 , the first heat absorbing layer 1041 and the first welding electrode 1031 are sequentially stacked on the insulating substrate 110 . Wherein, the second heat absorbing layer 1042, the second positive welding electrode 1032-1, the first heat absorbing layer 1041 and the first positive welding electrode 1031-1 form the first stack 121, the second heat absorbing layer 1042, the second negative welding electrode The electrode 1031-2, the first heat absorbing layer 1041 and the first negative welding electrode 1031-2 form the second stack 122, the first stack 121 and the second stack 122 are spaced apart from each other, and the first stack 121 and the second stack 122 are mutually spaced apart. The opposite side walls are all flush, and the side walls away from each other form a stepped structure. Specifically, as shown in FIG. 17 , the projected area of the second heat absorbing layer 1042 on the circuit substrate 100 > the projected area of the second welding electrode 1032 on the circuit substrate 100 > the projected area of the first heat absorbing layer 1041 on the circuit substrate 100 Projected area>projected area of the first welding electrode 1031 on the circuit board 100 . Thus, the second heat absorbing layer 1042 extends to the outside of the second welding electrode 1032 in three sidewall directions other than the sidewall of the flush structure, and the second welding electrode 1032 is between the sidewalls of the flush structure. The three outer sidewall directions all extend to the outside of the first heat absorbing layer 1041, and the first heat absorbing layer 1041 extends to the first welding electrode 1031 in the three sidewall directions other than the sidewall of the flush structure. outside, so that the laser radiation does not affect the heat absorbing layer 104.

When it is necessary to weld the LED chip at the first welding electrode 1031, it is only necessary to irradiate the heat absorbing layer 104 exposed outside the welding electrode 103 with the laser of the first wavelength. At this time, the first heat absorbing layer in the heat absorbing layer 104 1041 absorbs the laser energy of the first wavelength and generates heat, and then conducts the heat to the first welding electrode 1031, so that the metal of the first welding electrode 1031 is heated and melted to realize the welding of the LED chip. In an optional embodiment, materials that are easy to remove are selected for the first heat absorption layer 1041 and the first welding electrode 1031. When repairing the LED chip, the LED chip on the first welding electrode 1031 needs to be removed first, and then The LED chip is welded at the second welding electrode 1032 . At this time, firstly, the heat absorbing layer 104 exposed outside the welding electrode 103 is irradiated with laser light of the first wavelength, at this time, the first heat absorbing layer 1041 in the heat absorbing layer 104 absorbs the energy of the laser light of the first wavelength and heat, and then conduct the heat to the first welding electrode 1031, so that the metal of the first welding electrode 1031 is heated and melted, and the LED chip is removed. Then remove the remaining first welding electrode 1031 and remove the first heat absorbing material, and then use laser radiation with a second wavelength to irradiate the heat absorbing layer 104 exposed outside the welding electrode 103. At this time, the second absorbing material in the heat absorbing layer 104 The heat layer 1042 absorbs the energy of the laser with the second wavelength and generates heat, and then conducts the heat to the second welding electrode 1032 , so that the metal of the second welding electrode is heated and melted to realize the welding of the LED chip.

Optionally, the thickness of the first heat absorbing layer 1041 is between 0.5 μm and 5 μm, the thickness of the second heat absorbing layer 1042 is between 0.5 μm and 5 μm, and the first heat absorbing layer 1041 and the second heat absorbing layer 1042 The thickness can be the same or different. The thickness of the first welding electrode 1031 is between 10 μm and 20 μm, and the thickness of the second welding electrode 1032 is between 20 μm and 30 μm. The thickness of the first welding electrode 1031 and the first heat absorbing layer 1041 is set so that removing the first welding electrode 1031 and the first heat absorbing layer 1041 will not affect the first welding electrode after welding the LED chip on the second welding electrode 1032 The height of the LED chip at 1031 and the second welding electrode 1032 does not affect the overall flatness of the LED display device.

In addition, in order to realize the electrical connection between the stacked first welding electrode 1031 and the second welding electrode 1032 and the circuit layer 101, a through hole can be formed in the heat absorption layer 104, and the through hole is filled with conductive metal, so as to communicate with the first welding electrode. 1031 and the wiring layer 101, and the second welding electrode 1032 and the wiring layer 101.

The arrangement of the heat absorbing layer 104 and the welding electrode 103 in this embodiment is beneficial to reduce the area of the die-bonding region 1011 , and further facilitates the wiring arrangement of the circuit layer 101 . In addition, the first welding electrode 1031 and the first heat absorbing layer 1041 are made of materials that are easy to remove, so their removal will not affect the integrity of the second heat absorbing layer 1042 and the second welding electrode 1032, ensuring the yield of the repair process.

[Embodiment 9] This embodiment provides an LED display device 200 . As shown in FIG. 18 , the LED display device 200 of this embodiment includes, for example, a circuit substrate 100 and a plurality of LED chips 201 . The circuit substrate 100 is the circuit substrate 100 provided in Embodiment 7 or Embodiment 8 of the present application, and the descriptions of Embodiment 7 and Embodiment 8 may be referred to. The LED chip 201 is preferably a micro LED chip with a size smaller than 75 μm. The LED chip 201 includes a light-emitting epitaxial layer and electrodes (not shown). The light-emitting epitaxial layer includes a first semiconductor layer 3011 (such as an N-type GaN layer), an active layer 3013 above the first semiconductor layer 3011 (such as an InsGa1-sN/AlGaN multiple quantum well layer) and a second layer above the active layer 3013. The second semiconductor layer 3012 (such as a P-type GaN layer). The min LED chip is small in size and has no substrate. Therefore, when it is placed on the circuit substrate 100, the electrode is welded to the welding electrode 103 of the circuit substrate 100 by metal welding to realize the electrical connection between the LED chip 201 and the circuit substrate 100. .

As shown in FIG. 18 , a plurality of LED chips 201 are arranged in an array on the circuit substrate 100 , and the plurality of LED chips 201 can be arranged on the circuit substrate 100 in various suitable or required forms. The plurality of LED chips 201 includes a first chip 2011 disposed at the first welding electrode 1031 as a main light emitting element and at least one second chip 2012 disposed at the second welding electrode 1032 as a repairing light emitting element.

As shown in FIG. 19 , in an optional embodiment of this embodiment, the circuit substrate 100 is the circuit substrate 100 provided in Embodiment 7 of the present application. The first chip 2011 is located at the first welding electrode 1031. Since the first heat absorbing layer 1041 is arranged around the first welding electrode 1031 of the circuit substrate 100, when the first chip 2011 is welded, the laser with the first wavelength is used to irradiate the first chip 2011. A heat absorbing layer 1041, the first heat absorbing layer 1041 absorbs the heat of the laser energy conversion layer and transfers the heat to the first welding electrode 1031, so that the first welding electrode 1031 is heated and melted, and the electrode of the first chip 2011 is placed on the first welding electrode 1031 , the first welding electrode 1031 is cooled and solidified to achieve fixed welding of the first chip 2011 .

When a damaged or malfunctioning first chip 2011 appears in the LED display device 200, after finding the damaged or malfunctioning first chip 2011, the laser of the first wavelength is also used to irradiate the first heat absorber on the periphery of the first welding electrode 1031. layer 1041 , the first heat absorbing layer absorbs laser energy and converts it into heat, and conducts the heat to the first welding electrode 1031 , so that the first welding electrode 1031 melts, so that the first chip 2011 can be quickly removed. Then the second heat absorbing layer 1042 is irradiated with laser light of the second wavelength, and the second heat absorbing layer 1042 absorbs the heat of the laser energy conversion layer and transfers the heat to the second welding electrode 1032, so that the second welding electrode 1032 is heated and melted, and the second heat absorbing layer 1042 The electrodes of the chip 2012 are placed on the second welding electrode 1032 , and the second welding electrode 1032 is cooled and solidified to realize the fixed welding of the second chip 2012 .

As shown in FIG. 20 , in another alternative embodiment of this embodiment, the circuit substrate 100 is the circuit substrate 100 provided in Embodiment 7 of the present application. The first chip 2011 is located at the first welding electrode 1031. Since the welding electrode 103 and the heat absorbing layer 104 on the circuit substrate 100 are stacked and arranged, when welding the first chip 2011, laser irradiation with a first wavelength is used at the first welding electrode 1031. The first heat absorbing layer 1041 below the electrode 1031, the first heat absorbing layer 1041 absorbs the heat of the laser energy conversion layer and transfers the heat to the first welding electrode 1031, so that the first welding electrode 1031 is heated and melted, and the electrode of the first chip 2011 is placed On the first welding electrode 1031 , the first welding electrode 1031 is cooled and solidified to achieve fixed welding of the first chip 2011 .

When a damaged or malfunctioning first chip 2011 appears in the LED display device 200, after finding the damaged or malfunctioning first chip 2011, the first heat absorber under the first welding electrode 1031 is also irradiated with a laser of the first wavelength. layer 1041 , the first heat absorbing layer absorbs laser energy and converts it into heat, and conducts the heat to the first welding electrode 1031 , so that the first welding electrode 1031 melts, so that the first chip 2011 can be quickly removed. After the first chip 2011 is removed, the remaining first welding electrode 1031 is removed and the first heat absorbing layer 1041 is removed.

Then the second heat absorbing layer 1042 is irradiated with laser light of the second wavelength, and the second heat absorbing layer 1042 absorbs the heat of the laser energy conversion layer and transfers the heat to the second welding electrode 1032, so that the second welding electrode 1032 is heated and melted, and the second heat absorbing layer 1042 The electrodes of the chip 2012 are placed on the second welding electrode 1032 , and the second welding electrode 1032 is cooled and solidified to realize the fixed welding of the second chip 2012 .

In addition, the LED display device 200 of this embodiment also includes a bottom case, a face cover, and a power module (not shown in detail), the circuit substrate 100 is clamped between the face cover and the bottom case, and the face cover and the bottom case are fixed to each other to form an accommodating circuit substrate 100 and the cavity of the LED chip 201. The power module can also be arranged in the cavity formed by the bottom shell and the face cover, and the power module is connected with the circuit substrate 100 and an external power supply to supply power to the LED chip 201 in the LED display device 200 .

[Embodiment 10] This embodiment provides a light emitting element 300 . As shown in FIG. 21 , the light emitting element 300 includes a light emitting structure 301 , an electrode structure 304 and a heat absorbing layer 302 . The light emitting structure 301 has a light emitting surface 310 and a back surface 320 opposite to the light emitting surface 310 . The electrode structure 304 is formed on the back surface 320 of the light emitting structure 301 and is electrically connected with the light emitting structure 301 .

The heat absorbing layer 302 is located between the light emitting structure 301 and the electrode structure 304. In order to ensure the electrical connection between the electrode structure 304 and the light emitting structure 301, as shown in FIG. A plurality of through holes 305 are filled with conductive metal to realize the electrical connection between the electrode structure 304 and the light emitting structure 301 . At the same time, in order to ensure the performance of the heat absorbing layer 302 without affecting the light extraction and thickness of the light emitting element 300, in this embodiment, the thickness of the heat absorbing layer 302 is between 0.5 μm and 5 μm.

In this embodiment, the heat absorbing layer 302 is a single-layer structure, and the heat absorbing layer 302 is set as a laser absorbing material, such as a laser absorbing resin, in which a laser absorbing agent is added, and the laser absorbing agent contributes to laser absorption. Absorb and convert the absorbed laser light into heat. The heat absorbing layer 302 absorbs laser light of a certain wavelength and generates heat, and transfers the heat to the electrode structure 304 so that the metal layer of the electrode structure 304 is heated and melted to achieve welding or removal of the light emitting element 300 . For example, in this embodiment, as shown in FIG. 21, when the light-emitting element 300 is to be welded, the heat-absorbing layer 302 is irradiated with laser light of a certain wavelength, the heat-absorbing layer 302 absorbs the laser light and generates heat, and the heat is transferred to the electrode structure 304 so that The metal layer of the electrode structure 304 is melted to place the light-emitting element 300 at the welding position, and during the cooling process, the molten metal layer is solidified to weld and fix the light-emitting element 300 to the welding position. When the light-emitting element 300 needs to be removed, the heat-absorbing layer 302 is also irradiated with laser light of a certain wavelength, the heat-absorbing layer 302 absorbs the laser light and generates heat, and the heat is transferred to the electrode structure 304 to melt the metal layer of the electrode structure 304, which is convenient for removing the light-emitting element 300. Element 300.

Also as shown in FIG. 21, the light emitting structure 301 includes a first semiconductor layer 3011, a second semiconductor layer 3012, and an active layer 3013 located between the first semiconductor layer 3011 and the second semiconductor layer 3012. The active layer 3013 is a light emitting The light emitting layer of structure 301. Optionally, the first semiconductor layer 3011 may be an N-type semiconductor layer, and the second semiconductor layer 3012 may be a P-type semiconductor layer. It can be understood that a structure such as a transparent conductive layer may also be formed above the second semiconductor layer 3012 . Of course, it is also possible that the first semiconductor layer 3011 is a P-type semiconductor layer, and the second semiconductor layer 3012 is an N-type semiconductor layer. In an optional embodiment, the above-mentioned first semiconductor layer 3011 may be an n-type GaN layer, the active layer 3013 is a quantum well layer, and the second semiconductor layer 3012 is a p-type GaN layer. Alternatively, the first semiconductor layer 3011 may be an n-type GaN layer, the active layer 3013 may be an InGaN/GaN multiple quantum well, and the second semiconductor layer 3012 may be a p-type GaN layer. The electrode structure 304 includes a first electrode 3041 and a second electrode 3042 , wherein the first electrode 3041 is electrically connected to the first semiconductor layer 3011 , and the second electrode 3042 is electrically connected to the second semiconductor layer 3012 . It can be understood that, in order to enable the light-emitting element 300 to emit light from the light-emitting surface 310 , a reflective structure is also formed on the back surface 320 of the light-emitting structure 301 .

As shown in FIG. 21 , an insulating layer 303 is formed on the surface of the light emitting structure 301 , and the insulating layer 303 is formed on the surface of the light emitting structure 301 or on the surface and sidewalls of the light emitting structure 301 to protect the light emitting element 300 .

The arrangement of the heat absorbing layer 302 on the light emitting element 300 is convenient for heating the electrode structure 304 and facilitating the welding of the light emitting element 300 .

[Embodiment Eleven] This embodiment provides a light-emitting element. As shown in FIG. 23, the light-emitting element 300 includes a light-emitting structure 301, an electrode structure 304, and a heat-absorbing layer 302. 310 opposite the back 320 . The electrode structure 304 is formed on the back surface 320 of the light emitting structure 301 and is electrically connected with the light emitting structure 301 . The difference between this embodiment and Embodiment 10 is that in this embodiment, the heat absorbing layer 302 on the back side 320 of the light emitting element 300 has a two-layer or multi-layer structure. This embodiment takes a two-layer structure as an example, as shown in FIG. 23 , The heat absorption layer 302 includes a third heat absorption layer 3021 and a fourth heat absorption layer 3022 . The third heat absorption layer 3021 and the fourth heat absorption layer 3022 are stacked on the back surface 320 of the light emitting element 300 . The third heat-absorbing layer 3021 and the fourth heat-absorbing layer 3022 are configured to absorb laser light of different wavelengths, thereby generating unequal amounts of heat, and the generated heat can be passed between the third heat-absorbing layer 3021 and the fourth heat-absorbing layer 3022 transfer between. Therefore, when welding the light emitting element 300 or removing the light emitting element 300 , the third heat absorbing layer 3021 or the fourth heat absorbing layer 3022 can be irradiated with laser light of different wavelengths respectively. For example, when welding the light-emitting element 300, the fourth heat absorbing layer 3022 is irradiated with a laser with a fourth wavelength, and the heat generated by the fourth heat absorbing layer 3022 absorbing the laser energy is transferred to the electrode structure 304, so that the electrode structure 304 is melted, and the electrode structure 304 Soldering and fixing of the light emitting element 300 is realized during the cooling and solidification process. When the light-emitting element 300 needs to be removed, the third heat absorption layer 3021 is irradiated with laser light of the third wavelength, and the heat generated by the absorption of laser energy by the third heat absorption layer 3021 is transferred to the electrode structure 304 through the fourth heat absorption layer 3022, so that the electrode structure 304 is melted, at which point the light emitting element 300 can be quickly removed. Or when welding or removing the light-emitting element 300, the third and fourth wavelength lasers are used to irradiate the third heat absorption layer 3021 and the fourth heat absorption layer 3022, thereby speeding up the generation and transfer of heat and saving laser light. Irradiation time increases the efficiency of soldering or removal.

[Embodiment 12] This embodiment provides a light-emitting element. As shown in FIG. 24, the light-emitting element 300 includes a light-emitting structure 301, an electrode structure 304, and a heat-absorbing layer 302. 310 opposite the back 320 . The electrode structure 304 is formed on the back surface 320 of the light emitting structure 301 and is electrically connected with the light emitting structure 301 . The difference between this embodiment and the eleventh embodiment is that, as shown in FIG. 24 , in this embodiment, the third heat absorption layer 3021 and the fourth heat absorption layer 3022 are respectively located on the back of the light emitting structure 301 on the side of the first electrode 3041 320 and the back surface 320 of the light emitting structure 301 on the side of the second electrode 3042 . And the third heat absorption layer 3021 and the fourth heat absorption layer 3022 form a continuous structure on the back surface 320 of the light emitting structure 301 . The third heat-absorbing layer 3021 and the fourth heat-absorbing layer 3022 are arranged to absorb laser light of different wavelengths, thereby generating unequal amounts of heat, and the heat generated can be between the third heat-absorbing layer 3021 and the fourth heat-absorbing layer 3022 transfer. Therefore, when welding the light emitting element 300 or removing the light emitting element 300 , the third heat absorbing layer 3021 and the fourth heat absorbing layer 3022 can be irradiated with lasers of different wavelengths respectively. For example, when welding the light-emitting element 300, the third heat absorbing layer 3021 is irradiated with the laser of the third wavelength, and the fourth heat absorbing layer 3022 is irradiated with the laser of the fourth wavelength, and the heat generated by the absorption of the laser energy by the third heat absorbing layer 3021 is transferred to the The first electrode 3041 structure, the heat generated by the fourth heat absorbing layer 3022 absorbing laser energy is transferred to the second electrode 3042 structure, so that the electrode structure 304 is melted, and the light-emitting element 300 is welded and fixed during the cooling and solidification process of the electrode structure 304 . When the light-emitting element 300 needs to be removed, the third heat absorbing layer 3021 is irradiated with the laser of the third wavelength, and the fourth heat absorbing layer 3022 is irradiated with the laser of the fourth wavelength, and the third heat absorbing layer 3021 absorbs the heat generated by the laser energy to transfer To the structure of the first electrode 3041, the heat generated by the absorption of laser energy by the fourth heat absorbing layer 3022 is transferred to the structure of the second electrode 3042, so that the electrode structure 304 is melted, and the light emitting element 300 can be quickly removed at this time. Or when welding or removing the light emitting element 300, the third heat absorbing layer 3021 is irradiated with the third wavelength, or the fourth heat absorbing layer 3022 is irradiated with the laser of the fourth wavelength, the third heat absorbing layer 3021 or the fourth heat absorbing layer The heat generated by the 3022 absorbing laser energy is transferred between each other and to the electrode structure 304 , so that the electrode structure 304 is melted, and the light emitting element 300 is welded or removed.

[Embodiment Thirteen] This embodiment provides a light-emitting element. As shown in FIG. 25, the light-emitting element 300 includes a light-emitting structure 301, an electrode structure 304, and a heat-absorbing layer 302. 310 opposite the back 320 . The electrode structure 304 is formed on the back surface 320 of the light emitting structure 301 and is electrically connected with the light emitting structure 301 . The difference between this embodiment and Embodiment 12 is that, as shown in FIG. 25 , in this embodiment, the third heat absorption layer 3021 and the fourth heat absorption layer 3022 are also formed on the sidewall of the light emitting element 300 . Specifically: the third heat absorption layer 3021 extends to the first side wall of the light emitting element 300 on the side of the first electrode 3041, and the fourth heat absorption layer 3022 extends to the second side of the light emitting element 300 on the side of the second electrode 3042 on the wall. The above arrangement of the heat absorbing layer 302 increases the area of the heat absorbing layer 302 , that is, increases the area that can be irradiated by the laser, thereby increasing the heat generation and transfer efficiency, and improving the welding and removal efficiency of the light emitting element 300 . At the same time, since the heat absorbing layer 302 is made of an insulating material, it can further protect the light emitting element 300 .

In addition, it can be understood that the above-mentioned embodiments are only exemplary illustrations of the present application. On the premise that the technical features do not conflict, the structures do not contradict, and the application objective of the present application is not violated, the technical solutions of the various embodiments can be combined arbitrarily, For use with.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, rather than limiting them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present application.

Industrial Applicability

Type the industrial applicability description paragraph here.

Sequence Listing Free Content

Type the sequence listing free content description paragraph here.

Claims (20)

1. A circuit substrate, comprising:

   insulating substrate;

   A circuit layer, disposed on the insulating substrate, the circuit layer includes a die-bonding area, and the die-bonding area has welding electrodes for welding LED chips;

   The heat absorbing layer is in contact with the welding electrode and is used for conducting absorbed heat to the welding electrode.
2. The circuit substrate according to claim 1, wherein the heat absorbing layer is located below the welding electrode, and an edge of the heat absorbing layer exceeds an edge of the welding electrode.
3. The circuit substrate according to claim 2, wherein the heat absorbing layer is located under the entire welding electrode, and a through hole is provided in the heat absorbing layer, and the welding electrode communicates with the welding electrode through the through hole. Line layer connectivity.
4. The circuit substrate according to claim 2, wherein the heat absorbing layer is located below an edge region of the welding electrode.
5. The circuit substrate according to claim 1, wherein the heat absorbing layer is provided on a periphery of the welding electrode.
6. The circuit substrate according to claim 4 or 5, wherein the heat absorbing layer is formed into a ring structure, or a ring structure with a hollow structure.
7. The circuit substrate according to claim 4 or 5, wherein the heat absorbing layer is formed on a side of the welding electrodes in the same die-bonding area away from each other; the heat absorbing layer forms a stripe structure.
8. The circuit substrate according to claim 1, wherein the heat absorbing layer forms a strip-like structure with a hollow structure.
9. The circuit substrate according to claim 1, wherein the circuit substrate further comprises an insulating layer, the insulating layer is disposed on a side of the wiring layer away from the insulating substrate, and exposes the welding electrodes.
10. The circuit substrate according to claim 1, wherein the thickness of the heat absorbing layer is between 0.5 μm and 5 μm.
11. The circuit substrate according to claim 1, wherein the welding electrodes include a first welding electrode and a second welding electrode as a repair pad;

    The heat absorbing layer includes a first heat absorbing layer and a second heat absorbing layer, the first heat absorbing layer and the second heat absorbing layer are respectively in contact with the first welding electrode and the second welding electrode, The first heat absorbing layer and the second heat absorbing layer are used to absorb laser light of different wavelengths, and conduct the absorbed heat to the welding electrodes.
12. The circuit substrate according to claim 11, wherein the first welding electrode and the second welding electrode are arranged side by side with a distance from each other;

    The first heat absorbing layer is arranged around the first welding electrode, the second heat absorbing layer is arranged around the second welding electrode, and the first heat absorbing layer and the second heat absorbing layer Layers are arranged side by side with each other;

    Or the first heat absorbing layer is arranged under and around the first welding electrode, the second heat absorbing layer is arranged under and around the second welding electrode, and the first heat absorbing layer and the The second heat absorbing layers are arranged side by side.
13. The circuit substrate according to claim 11, wherein, along the direction from the insulating substrate to the wiring layer, the second heat absorbing layer, the second welding electrode, the first heat absorbing layer and the The first welding electrodes are stacked sequentially.
14. The circuit substrate according to claim 13, wherein the second heat absorbing layer, the second welding electrode, the first heat absorbing layer and the first welding electrode are stacked in sequence to form a first stack and a second stack spaced apart from each other. Two stacks, the opposite sides of the first stack and the second stack are flush side walls.
15. The circuit substrate according to claim 12 or 13, wherein the melting point of the first welding electrode is lower than the melting point of the second welding electrode.
16. A LED display device, comprising:

    The circuit substrate according to any one of claims 1 to 15; and

    The LED chip is welded on the circuit substrate.
17. A light emitting element, comprising:

    A light-emitting structure, the light-emitting structure has a light-emitting surface;

    an electrode structure disposed on the back of the light emitting structure away from the light emitting surface to form an electrical connection with the light emitting structure;

    A heat absorbing layer is formed on the back of the light emitting structure and surrounds the electrode structure, the heat absorbing layer absorbs the heat of the laser light and conducts the absorbed heat to the electrode structure.
18. The light-emitting element according to claim 17, wherein the heat absorbing layer comprises at least one heat absorbing layer, and when the heat absorbing layer comprises two or more heat absorbing layers, multiple layers of the heat absorbing layer stacked on the back of the light-emitting structure in sequence.
19. The light emitting element according to claim 17, wherein the heat absorbing layer comprises a first heat absorbing layer and a second heat absorbing layer, and the first heat absorbing layer and the second heat absorbing layer are used to absorb different wavelengths laser, the electrode structure includes a first electrode and a second electrode, the first heat absorbing layer is formed on the side of the back where the first electrode is located, and the second heat absorbing layer is formed on the On the side of the back where the second electrode is located, and the first heat absorbing layer and the second heat absorbing layer form a continuous structure.
20. The light emitting element according to claim 19, wherein the first heat absorbing layer is further formed on the first side wall of the light emitting structure on the side of the first electrode, and the second heat absorbing layer is further formed on On the second side wall of the light emitting structure on the side of the second electrode.