Light-emitting chip bonding substrate, manufacturing method thereof and light-emitting device

Abstract

The invention relates to a light-emitting chip bonding substrate, a manufacturing method thereof and a light-emitting device. The light-emitting chip bonding substrate comprises a base material; the first conducting layer is arranged on one side of the base material and comprises a bonding area used for arranging a light-emitting chip; and the second conducting layer completely covers the bonding area, is black and has the property of conducting in the vertical direction and not conducting in the horizontal direction. The black second conductive layer covers the bonding area, so that the bonding area is shielded while the electric connection of the light-emitting chip is ensured, and the contrast ratio is improved.

Description

Technical Field

[0001] The present application relates to the field of chip packaging, and in particular to a light-emitting chip bonding substrate, a manufacturing method thereof, and a light-emitting device. Background Art

[0002] Display packaging technology is a key link between display pixels and driver circuits, with the black matrix playing a crucial role. The black matrix, a sophisticated black matrix structure consisting of one or more layers, sits between pixels, providing optical isolation and boundary definition. In display technology, the black matrix significantly improves screen contrast and color purity by absorbing stray light and preventing crosstalk between adjacent pixels, thereby enhancing image quality.

[0003] However, during the bonding process of the light-emitting chip, since a bonding area for the light-emitting chip needs to be reserved, the black matrix cannot shield the bonding area where the light-emitting chip is set, resulting in limited improvement in contrast.

[0004] Therefore, how to further improve the display contrast is an urgent problem to be solved. Summary of the Invention

[0005] In view of the deficiencies of the above-mentioned related technologies, the purpose of the present application is to provide a light-emitting chip bonding substrate and a manufacturing method thereof and a light-emitting device, aiming to solve the problem of insufficient contrast of display products.

[0006] A light-emitting chip bonding substrate, comprising:

[0007] substrate;

[0008] a first conductive layer provided on one side of the substrate, the first conductive layer including a bonding area for arranging a light-emitting chip; and

[0009] A second conductive layer completely covers the bonding area, wherein the second conductive layer is black and has the property of being conductive in a vertical direction and non-conductive in a horizontal direction.

[0010] The light emitting chip bonding substrate uses the black second conductive layer to cover the bonding area, so that even around the electrodes of the light emitting chip, the underlying conductive layer is not exposed, thereby ensuring the electrical connection of the light emitting chip and shielding the bonding area, thereby improving the contrast.

[0011] Optionally, the second conductive layer includes an adhesive resin and conductive particles distributed in the adhesive resin, and the conductive particles are sandwiched between the second conductive layer and the electrode of the light-emitting chip to enable conduction between the second conductive layer and the electrode of the light-emitting chip.

[0012] The adhesive resin can not only disperse the conductive particles, but also play a bonding role. The light-emitting chip can be bonded and fixed through the adhesive resin. In some implementation processes, there is no need for traditional solder welding, which avoids high temperatures during the welding process and thus avoids the deterioration of colloidal materials such as the adhesive resin at high temperatures.

[0013] Optionally, the conductive particles include metal particles and carbon black particles.

[0014] The metal particles have a better conductive effect, and the carbon black particles used for shading can also conduct electricity. By mixing the metal particles and the carbon black particles, the influence of adding black shading material to the second conductive layer on its conductive properties is reduced, and a better conductive effect is maintained.

[0015] Optionally, the volume percentage of the metal particles in the second conductive layer ranges from 20% to 40%, and the particle size ranges from 40nm to 60nm; the volume percentage of the carbon black particles in the second conductive layer ranges from 10% to 20%, and the particle size ranges from 30nm to 50nm.

[0016] By using conductive particles with smaller particle sizes and appropriately higher volume percentages, sufficient conductive particles are easily present in a smaller contact area to provide stable conductive connection capabilities, and the smaller particle size also makes it less likely for short circuits to occur in the horizontal direction.

[0017] Optionally, the second conductive layer covers the entire surface of one side of the device region where the light-emitting chip is disposed.

[0018] The second conductive layer can completely replace the traditional black matrix, covering all places that need to be shielded, and can simplify the production process and structure of the light-emitting chip bonding substrate.

[0019] Optionally, the first conductive layer or the third conductive layer also includes a test lead arranged outside the device area and at least two test pads corresponding to the first pad and the second pad, respectively, the test lead connecting each of the device pads with the corresponding test pad, and the size of the test pad is larger than any pad in the device area.

[0020] The device pads are directly connected to the corresponding test pads in the light-emitting chip bonding substrate, so that after the light-emitting chip is transferred to the light-emitting chip bonding substrate, it can be directly lit up for testing through the additional test pads. The test pads are set outside the device area and can be made very large in size, so it is efficient and the testing difficulty is low.

[0021] Based on the same inventive concept, the present application also provides a method for manufacturing a light-emitting chip bonding substrate, comprising:

[0022] providing a substrate;

[0023] Disposing a first conductive layer on one side of the substrate, wherein the first conductive layer includes a bonding area for disposing a light-emitting chip; and

[0024] A second conductive layer is provided to completely cover the bonding area. The second conductive layer is black and has the property of being conductive in the vertical direction and non-conductive in the horizontal direction.

[0025] The light-emitting chip bonding substrate prepared by the above method uses a black second conductive layer to cover the bonding area, so that even around the electrodes of the light-emitting chip, the underlying conductive layer will not be exposed, ensuring the electrical connection of the light-emitting chip while shielding the bonding area, thereby improving the contrast.

[0026] Based on the same inventive concept, the present application also provides a light-emitting device, comprising any of the above-mentioned light-emitting chip bonding substrates or a portion of a substrate cut from the light-emitting chip bonding substrate, and a light-emitting chip arranged on the second conductive layer.

[0027] The light-emitting device has a black second conductive layer, which covers the bonding area so that the underlying conductive layer is not exposed even around the electrodes of the light-emitting chip. This ensures the electrical connection of the light-emitting chip while shielding the bonding area, thereby improving the contrast. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Schematic diagram of the cross-sectional structure of the light-emitting chip bonding substrate provided in the embodiment of the present application Figure 1 ;

[0029] Figure 2 Schematic diagram of the cross-sectional structure of the light-emitting chip bonding substrate provided in the embodiment of the present application Figure 2 ;

[0030] Figure 3 Schematic diagram of the cross-sectional structure of the light-emitting chip bonding substrate provided in the embodiment of the present application Figure 3 ;

[0031] Figure 4 A schematic diagram of the structure of a traditional bonding substrate with a black matrix;

[0032] Figure 5 Schematic diagram of the planar structure of the light-emitting chip bonding substrate provided in the embodiment of the present application Figure 1 ;

[0033] Figure 6 Schematic diagram of the cross-sectional structure of the light-emitting chip bonding substrate provided in the embodiment of the present application Figure 4 ;

[0034] Figure 7 A schematic diagram of conductive hole electroplating provided in an embodiment of the present application;

[0035] Figure 8 Schematic diagram of the planar structure of the light-emitting chip bonding substrate provided in the embodiment of the present application Figure 2 ;

[0036] Figure 9 Schematic diagram of the planar structure of the light-emitting chip bonding substrate provided in the embodiment of the present application Figure 3 ;

[0037] Figure 10 A schematic diagram of the basic process of the method for manufacturing a light-emitting chip bonding substrate provided in an embodiment of the present application;

[0038] Description of reference numerals:

[0039] 1-substrate; 2-first conductive layer; 21-first solder pad; 22-second solder pad; 23-test lead; 24-test solder pad; 3-second conductive layer; 31-adhesive resin; 32-conductive particles; 321-metal particles; 322-carbon black particles; 4-light-emitting chip; 5-black matrix; 6-device area; 7-third conductive layer; 8-conductive hole; 81-pit; 82-void DETAILED DESCRIPTION

[0040] To facilitate understanding of the present application, a more comprehensive description of the present application will be provided below with reference to the accompanying drawings. The accompanying drawings illustrate preferred embodiments of the present application. However, the present application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of the present application.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0042] In the related art, during the bonding process of the light-emitting chip, a bonding area for the light-emitting chip needs to be reserved. However, the black matrix cannot block the bonding area where the light-emitting chip is set, resulting in a limited improvement in contrast. Based on this, the present application hopes to provide a solution that can solve the above technical problems, and its details will be explained in the subsequent embodiments.

[0043] Example:

[0044] This embodiment provides a light-emitting chip bonding substrate, which can be used to bond the light-emitting chip 4. The black second conductive layer 3 completely covers the bonding area, completely shielding the bonding area, ensuring the coverage of the black area, so that it can have a higher contrast in display applications.

[0045] See also Figure 1 The light-emitting chip bonding substrate includes a substrate 1, a first conductive layer 2 and a second conductive layer 3. The first conductive layer 2 is arranged on one side of the substrate 1 and includes a bonding area for arranging the light-emitting chip 4, and the second conductive layer 3 completely covers the bonding area of ​​the first conductive layer 2. In practical applications, in order to ensure effective electrical connection, the bonding area can be larger than the size of the light-emitting chip 4. The bonding area refers to the area used for direct bonding with the light-emitting chip 4, that is, the area directly below the light-emitting chip 4. In some implementations, the first conductive layer 2 may also include wiring lines and other conductive patterns connected to the bonding area. The second conductive layer 3 has the characteristics of being conductive in the vertical direction and non-conductive in the horizontal direction. That is to say, when the light-emitting chip 4 is arranged on the light-emitting chip bonding substrate, the light-emitting chip 4 can be electrically connected to the first conductive layer 2 below through the second conductive layer 3, but the remaining areas of the second conductive layer 3 are not conductive. It should be understood that the second conductive layer 3 is conductive in the vertical direction and non-conductive in the horizontal direction under certain conditions (such as pressing). Specifically, in the present application, the second conductive layer 3 can enable the light-emitting chip 4 to be electrically connected to the first conductive layer 2 after being set. The present application is not limited to the second conductive layer 3 always having the property of being conductive in the vertical direction under any conditions. Figure 1 As shown, the thickness direction referred to in this application is the thickness direction of the substrate 1, and the horizontal direction is the plane direction of the substrate 1 shown in the figure.

[0046] The first conductive layer 2 can be made of a metallic conductive material, including but not limited to at least one of Cr, Ni, Al, Ti, Au, Pt, W, Pb, Rh, Sn, Cu, and Ag. Some metallic conductive materials may have a certain degree of reflectivity, but because this embodiment uses a black second conductive layer 3 covering the bonding area, even using a metallic conductive material does not affect the display contrast. The light-emitting chip bonding substrate can be a PCB board, or it can be a glass substrate or other substrate capable of bonding the light-emitting chip 4.

[0047] As an embodiment, the second conductive layer 3 may include an adhesive resin 31 and conductive particles 32 distributed in the adhesive resin 31. When the conductive particles 32 are sandwiched between the second conductive layer 3 and the electrode of the light emitting chip 4, the second conductive layer 3 and the light emitting chip 4 are electrically connected. Figure 2As shown, a large number of conductive particles 32 are distributed in the adhesive resin 31. These conductive particles 32 have no specific connection relationship with each other. In their natural state, these conductive particles 32 cannot form a continuous conductive path. When the light-emitting chip 4 is bonded, the second conductive layer 3 is pressed so that the conductive particles 32 in the pressed position are squeezed between the light-emitting chip 4 and the first conductive layer 2, thereby forming an electrical connection between the light-emitting chip 4 and the first conductive layer 2. The adhesive resin 31 not only disperses the conductive particles 32, but also acts as a bond, so that the light-emitting chip 4 can be bonded and fixed by the adhesive resin 31.

[0048] Unlike conventional anisotropic conductive adhesives or films, the second conductive layer 3 of the present application is black. The black color of the second conductive layer 3 can be achieved by adding black particles or other black dyes. For example, the colloidal substrate of the second conductive layer 3 can be a transparent or light-transmitting resin, which is rendered black overall by adding black dyes or black particles.

[0049] like Figure 3 As shown, in some embodiments, the conductive particles 32 in the second conductive layer 3 include metal particles 321 and carbon black particles 322. The carbon black particles 322 are black, which can change the color of the second conductive layer 3 while ensuring conductivity, thereby providing a black light-shielding effect. The metal particles 321 have a good conductivity, while the carbon black particles 322, which provide light-shielding properties, are also conductive. By combining the metal particles 321 and the carbon black particles 322, the effect of adding the black light-shielding material to the second conductive layer 3 on its conductivity is reduced, maintaining a good conductive effect.

[0050] In other embodiments, the conductive particles 32 in the second conductive layer 3 may be solely metal particles 321, with the black particles or other black dyes not providing conductivity. In these embodiments, the proportion of metal particles 321 may be appropriately increased to ensure conductivity. In other embodiments, the metal particles 321 may be partially or entirely black. In these cases, the proportion of other black dyes may be appropriately reduced to ensure conductivity.

[0051] It should be noted that the metal particles 321 in this application refer to the conductive portion of the particles containing metal. Metal particles 321 can be made entirely of metal or mixed with other materials. For example, in some examples, metal particles 321 can be plastic particles with a metal coating on their surface. The compressibility of the plastic core can increase the conductive contact area of ​​metal particles 321 and reduce on-resistance in some processes. Similarly, carbon black particles 322 can be made entirely of carbon black or mixed with other materials, with the carbon black portion used to provide the black color.

[0052] Taking the mixture of metal particles 321 and carbon black particles 322 as an example, in some embodiments, the volume percentage of the metal particles 321 in the second conductive layer 3 (hereinafter referred to as volume percentage, refers to the volume percentage in the second conductive layer 3) ranges from 20% to 40%, and the particle size ranges from 40nm to 60nm; the volume percentage of the carbon black particles 322 ranges from 10% to 20%, and the particle size ranges from 30nm to 50nm. For example, the volume percentage of the metal particles 321 can be 25%, 30%, 35%, etc., and the particle size can be 45nm, 50nm, 55nm, etc.; the volume percentage of the carbon black particles 322 can be 13%, 16%, 19%, etc., and the particle size can be 35nm, 40nm, 45nm, etc. In this embodiment, both the metal particles 321 and the carbon black particles 322 use smaller particle sizes, which can provide more stable performance when meeting the packaging requirements of the small light-emitting chip 4. The light-emitting chip 4 can be, for example, a MicroLED (Micro Light Emitting Diode) chip or a MiniLED (Mini Light Emitting Diode) chip. MicroLED and MiniLED chips are extremely small, and the distribution density of larger conductive particles 32 is low, making it difficult to ensure a stable conductive connection over a small contact area. Simply increasing the density of the conductive particles 32 can easily lead to horizontal congestion and short circuits among the conductive particles 32. The above embodiment utilizes smaller conductive particles 32 with a higher volume percentage, ensuring sufficient conductive particles 32 to provide a stable conductive connection over a smaller contact area. The smaller particle size also reduces the likelihood of horizontal short circuits. As a specific example, the volume percentage of the metal particles 321 is no less than 30%, which can provide better conductivity. At the same time, the volume percentage of the carbon black particles 322 is no less than 15%, ensuring both conductivity and the purity of the black color.

[0053] like Figure 4 As shown, in conventional packaging processes, the bonding area cannot be completely shielded by the black matrix 5. Furthermore, to ensure bonding of the light-emitting chip 4, a space larger than the electrode size of the light-emitting chip 4 is typically left to provide a certain degree of error tolerance. Consequently, the exposed bonding area A affects the display contrast. The light-emitting chip bonding substrate of this embodiment utilizes a black second conductive layer 3 to cover the bonding area, ensuring that even around the electrodes of the light-emitting chip 4, the underlying conductive layer is not exposed. This ensures electrical connection of the light-emitting chip 4 while shielding the bonding area, thereby improving contrast.

[0054] In some embodiments, the light-emitting chip 4 can be placed on the second conductive layer 3 by pressing, hot pressing, or the like, and fixed by the viscosity or curing properties of the second conductive layer 3 itself. In some implementations, there is no need for traditional solder welding, which avoids high temperatures during the welding process, thereby also avoiding the deterioration of colloid materials such as the adhesive resin 31 at high temperatures. At the same time, when bonding the light-emitting chip 4, it is only necessary to directly cover the entire bonding area, without having to accurately expose the bonding area, which also reduces the requirements for process accuracy and increases the precision tolerance for bonding the light-emitting chip 4. Therefore, the light-emitting chip bonding substrate of this embodiment is also conducive to providing higher product yield and stability.

[0055] In this embodiment, the second conductive layer 3 can be disposed only around the bonding area, that is, near the location of the electrodes of the light-emitting chip 4. Conventional black matrix materials can be used to shield other areas. In some embodiments, to further simplify the manufacturing process and structure of the light-emitting chip bonding substrate, the second conductive layer 3 can completely replace the conventional black matrix 5, covering all areas that require shielding.

[0056] Exemplarily, the light-emitting chip bonding substrate can be a backlight backplane or a display circuit board, which can be used as a backlight source and a display panel after the light-emitting chip 4 is bonded thereon; in some implementation processes, the light-emitting chip bonding substrate can also be a packaging substrate, which can be formed into an independent packaging device after the light-emitting chip 4 is arranged thereon, and the packaging device can be used as a light source unit, and the packaging device can be set on the backlight backplane or the display circuit board as a single light-emitting lamp bead or RGB pixel unit.

[0057] As an example, see Figure 5As shown, the light-emitting chip bonding substrate includes several device regions 6. The first conductive layer 2 within each device region 6 includes at least three first pads 21 for connecting to the first electrode of the light-emitting chip 4, and at least one second pad 22 for connecting to the second electrode of the light-emitting chip 4. Each device region 6 can accommodate at least three light-emitting chips 4. In practical applications, at least three light-emitting chips 4 emitting at blue, red, and green wavelengths can be provided, thereby forming RGB full-color pixels within a single device region 6. In some implementations, the first electrodes of these light-emitting chips 4 can be connected to the first pads 21 in a one-to-one correspondence, while the second electrodes can be connected to the second pads 22 simultaneously, thereby enabling independent control of the light emission of each light-emitting chip 4 and achieving an RGB full-color display effect. In this application, the first electrode and the second electrode are used to distinguish the positive and negative electrodes of the light-emitting chip 4. The first electrode can be either positive or negative, while the second electrode is a electrode with the opposite polarity to the first electrode. In this application, the light-emitting chips 4 can be arranged within the device region 6, and these light-emitting chips 4 can be packaged or used as a unit of the device region 6. For example, after the light emitting chip 4 is provided, the light emitting chip 4 is packaged, and each device region 6 is cut and separated to form an independent packaged device.

[0058] To simplify the manufacturing process and structure, the second conductive layer 3 can cover the entire surface of the device region 6 on the side where the light-emitting chip 4 is disposed. In practical applications, a light-emitting chip bonding substrate can be provided with multiple device regions 6 to transfer light-emitting chips 4 in batches and form multiple independent packaged devices. The side of the light-emitting chip bonding substrate where the light-emitting chip 4 is disposed can be entirely covered with the second conductive layer 3. In other words, the second conductive layers 3 of different device regions 6 can be connected as a whole.

[0059] See also Figure 5 In some embodiments, the light-emitting chip bonding substrate further includes a conductive hole 8 and a third conductive layer 7 provided on the substrate 1 and on the opposite side of the first conductive layer 2. The conductive hole 8 penetrates the thickness direction of the substrate 1 from the first conductive layer 2 until it is connected to the third conductive layer 7. The third conductive layer 7 includes device pads that are connected to the first pad 21 and the second pad 22 in a one-to-one correspondence. After the light-emitting chip bonding substrate encapsulated with the light-emitting chip 4 is divided into a plurality of independent packaged devices according to the device area 6 as a unit, the device pads of each packaged device can be used to connect to the circuit board. The conductive hole 8 may include conductive materials such as copper, and these conductive materials may be provided in the conductive hole 8 by, for example, electroplating. As Figure 5 For example, the conductive holes 8 can correspond to the number of pads on the first conductive layer 2 one by one, and the conductive pattern of the first conductive layer 2 extends to the four corners of the device area 6, and is electrically connected to the third conductive layer 7 on the other side through the conductive holes 8 at the four corners of the device area 6. For ease of understanding, Figure 5 The second conductive layer 3 is omitted, see Figure 6 , which is a cross-sectional schematic diagram of the conductive hole 8 penetrating the thickness direction of the substrate 1 from the first conductive layer 2 to connecting to the third conductive layer 7.

[0060] like Figure 7 As shown, due to the slow exchange rate of the liquid in the conductive hole 8 during electroplating, the conductive hole 8 with a large depth-to-width ratio is prone to structural defects such as pits 81 and voids 82. As another example, the conductive hole 8 can also be shared by multiple pads, see Figure 8 Larger conductive vias 8 can be set at the center of four adjacent 2*2 device regions 6. Device regions 6 at the boundaries can be shared by two or still have larger conductive vias 8. Sharing conductive vias 8 not only significantly reduces the total number of conductive vias 8, reducing drilling time and cost, but also increases the diameter of individual conductive vias 8, resulting in better yields during copper plating and other processes, reducing structural defects such as pits 81 and voids 82, and lowering process difficulty.

[0061] In some embodiments, the first conductive layer 2 or the third conductive layer 7 further includes a test lead 23 arranged outside the device region 6 and at least two test pads 24 corresponding to the first pad 21 and the second pad 22, respectively. Figure 9 ,for Figure 8 The schematic diagram of the conductive hole 8 is omitted, and the test lead 23 connects each device pad to the corresponding test pad 24. The size of the test pad 24 is larger than any pad in the device area 6. Exemplarily, only two test pads 24 can be set, corresponding to the positive and negative poles respectively. The positive pole in each device pad is connected to the positive test pad 24, and the negative pole in each device pad is connected to the negative test pad 24. By energizing the test pad 24, the light-emitting chips 4 in multiple device pads can be lit at the same time, achieving the purpose of lighting the light-emitting chips 4 after they are set. Especially in the scenario of small-sized chips such as Micro LED chips or MiniLED chips, after the light-emitting chip 4 is transferred to the light-emitting chip bonding substrate, the extremely small size makes spot testing difficult, and it is usually necessary to package and cut it and then perform it in units of single packaged devices. Directly connecting the device pads to the corresponding test pads 24 on the light-emitting chip bonding substrate allows the light-emitting chip 4 to be directly illuminated and tested via the additional test pads 24 after being transferred to the light-emitting chip bonding substrate. The test pads 24 are located outside the device area 6 and can be made larger, resulting in efficient and low-complexity testing. In practical applications, after testing is completed, the light-emitting chip bonding substrate can be cut according to the device area 6 to form independent packaged devices. At this point, the test pads 24 and test leads 23 can also be removed.

[0062] This embodiment also provides a method for manufacturing a light-emitting chip bonding substrate. Figure 10 ,include:

[0063] S101, providing a substrate;

[0064] S102, disposing a first conductive layer on one side of the substrate, wherein the first conductive layer includes a bonding area for disposing a light-emitting chip;

[0065] Taking metal conductive material as an example, the first conductive layer 2 can be deposited on the surface of the substrate 1 and a required circuit pattern can be realized through a patterning process such as photolithography.

[0066] S103, providing a second conductive layer that completely covers the bonding area, wherein the second conductive layer is black and has the property of being conductive in the vertical direction and non-conductive in the horizontal direction;

[0067] Taking the example of a second conductive layer 3 comprising a binder resin 31 and conductive particles 32 distributed within the binder resin 31, after the conductive particles 32 are mixed with the binder resin 31, they can be applied to the surface of the substrate 1 by methods including, but not limited to, coating. In some implementations, to simplify the fabrication process, the second conductive layer 3 can be applied entirely to the substrate 1, with the first conductive layer 2 completely covering it.

[0068] In some embodiments, the light-emitting chip bonding substrate further includes a third conductive layer 7 and a conductive hole 8, and the step of setting the third conductive layer 7 and the conductive hole 8 is also included. The second conductive layer 3 can be set on the surface of the light-emitting chip bonding substrate after the third conductive layer 7 and the conductive hole 8 are completed. At this time, the second conductive layer 3 can also cover the conductive hole 8.

[0069] In the above-described method for fabricating a light-emitting chip bonding substrate, the light-emitting chip bonding substrate is fabricated in such a way that the second conductive layer 3 completely covers the bonding area of ​​the first conductive layer 2. The light-emitting chip 4 can be directly electrically connected to the first conductive layer 2 via the second conductive layer 3. The black second conductive layer 3 ensures that the area surrounding the bonding area of ​​the light-emitting chip 4 also appears black, ensuring display contrast. In some implementations, solder bonding can be omitted, and the light-emitting chip 4 can be bonded directly to the second conductive layer 3, avoiding potential damage during high-temperature soldering.

[0070] This embodiment further provides a light-emitting device, which includes the above-mentioned light-emitting chip bonding substrate or a portion of a substrate cut from the light-emitting chip bonding substrate, and a light-emitting chip 4 disposed on the second conductive layer 3 .

[0071] It is understandable that the light emitting chip bonding substrate can be a backlight backplane or a display circuit board, or a packaging substrate specifically used to package the light emitting chip 4. The light emitting device of this embodiment can be a backlight source or a display panel. When the light emitting chip bonding substrate is used as a packaging substrate, it is usually provided with light emitting chips 4 corresponding to a plurality of packaging devices. After the transfer of the light emitting chip 4 and the subsequent packaging steps are completed, the light emitting chip bonding substrate can be divided according to the device area 6 to obtain a plurality of independent packaging devices. The light emitting device of this embodiment can also be the packaging device obtained thereby. For example Figure 5 or Figure 8 In the example, the light-emitting chip bonding substrate can be divided according to the device area 6. Each packaged device includes three light-emitting chips 4. The first electrode of each light-emitting chip 4 is connected to a first pad 21 in a one-to-one correspondence, and the second electrode is simultaneously connected to a second pad 22. When these light-emitting chips 4 are red, blue, and green light-emitting chips 4, respectively, this packaged device can achieve full-color RGB lighting control. When these light-emitting chips 4 are Micro LED chips, the resulting packaged device can also be called a MIP (Micro LED in Package) chip.

[0072] It should be understood that the application of this application is not limited to the above examples. For ordinary technicians in this field, they can make improvements or changes based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to this application.

Claims

1. A light-emitting chip bonding substrate, characterized in that: include: substrate; a first conductive layer provided on one side of the substrate, the first conductive layer including a bonding area for arranging a light-emitting chip; as well as A second conductive layer completely covers the bonding area, wherein the second conductive layer is black and has the property of being conductive in a vertical direction and non-conductive in a horizontal direction.

2. The light-emitting chip bonding substrate according to claim 1, wherein: The second conductive layer includes an adhesive resin and conductive particles distributed in the adhesive resin. When the conductive particles are sandwiched between the second conductive layer and the electrode of the light emitting chip, the second conductive layer and the electrode of the light emitting chip are electrically connected.

3. The light-emitting chip bonding substrate according to claim 2, wherein: The conductive particles include metal particles and carbon black particles.

4. The light-emitting chip bonding substrate according to claim 3, wherein: In the second conductive layer, the volume percentage of the metal particles ranges from 20% to 40%, and the particle size ranges from 40nm to 60nm; in the second conductive layer, the volume percentage of the carbon black particles ranges from 10% to 20%, and the particle size ranges from 30nm to 50nm.

5. The light-emitting chip bonding substrate according to any one of claims 1 to 4, wherein: The light-emitting chip bonding substrate includes several device areas, and the first conductive layer in each device area includes at least three first pads for connecting to the first pole of the light-emitting chip, and at least one second pad for connecting to the second pole of the light-emitting chip.

6. The light-emitting chip bonding substrate according to claim 5, wherein: The second conductive layer covers the entire surface of the device region on one side where the light-emitting chip is disposed.

7. The light-emitting chip bonding substrate according to claim 5, wherein: The light-emitting chip bonding substrate also includes a conductive hole and a third conductive layer arranged on the substrate and on the opposite side of the first conductive layer. The conductive hole penetrates the thickness direction of the substrate from the first conductive layer until it is connected to the third conductive layer. The third conductive layer includes device pads connected to the first pad and the second pad in a one-to-one correspondence.

8. The light-emitting chip bonding substrate according to claim 7, wherein: The first conductive layer or the third conductive layer also includes a test lead arranged outside the device area and at least two test pads corresponding to the first pad and the second pad respectively, the test lead connects each of the device pads with the corresponding test pad, and the size of the test pad is larger than any pad in the device area.

9. A method for manufacturing a light-emitting chip bonding substrate, characterized in that: include: providing a substrate; A first conductive layer is provided on one side of the substrate, wherein the first conductive layer includes a bonding area for arranging a light-emitting chip; as well as A second conductive layer is provided to completely cover the bonding area. The second conductive layer is black and has the property of being conductive in the vertical direction and non-conductive in the horizontal direction.

10. A light emitting device, characterized in that: The light-emitting chip bonding substrate comprises the light-emitting chip bonding substrate according to any one of claims 1 to 8 or a portion of the substrate cut from the light-emitting chip bonding substrate, and a light-emitting chip arranged on the second conductive layer.

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