Light-emitting substrate and method for manufacturing same

Abstract

According to an embodiment of the present invention, a light emitting substrate and a manufacturing method thereof are provided. In the manufacturing method of the light emitting substrate according to the embodiment of the present invention, by providing a groove in the bottom plate, the application accuracy of the solder resist ink layer is improved, the distance between the solder resist ink layer and the pad assembly is shortened, and the occurrence of poor welding or welding failure due to the solder resist ink overflowing onto the pad is avoided.

Description

[Technical field]

[0001] The present invention relates to the field of display technology, and in particular to a light-emitting substrate and a method for manufacturing the same. [Background technology]

[0002] The main development direction of MLED (Mini-LED) technology is divided into two parts: backlight and direct display. Whether it is a direct display product or a backlight product, the surface of the MLED package structure needs to be coated with solder resist ink.

[0003] Currently, MLED products have increasingly higher requirements for the application accuracy of solder resist ink, i.e., it is necessary to reduce the distance between the solder resist ink and the pad. However, when trying to improve the application accuracy of solder resist ink using the conventional ink application process, the phenomenon of the solder resist ink overflowing onto the pad, i.e., the solder resist ink covering a part or the entire surface of the pad, often occurs. If the solder resist ink is covered on the pad, it often causes poor welding or welding failure during the process of welding to the LED chip. Summary of the Invention [Problem to be solved by the invention]

[0004] Advantageous Effects of Invention According to an embodiment of the present invention, a light emitting substrate capable of preventing welding defects or failure due to solder resist ink overflowing onto a pad and a manufacturing method thereof are provided. [Means for solving the problem]

[0005] According to a first aspect of the present invention, providing a first substrate including a base plate and a pad assembly attached to a mounting surface of the base plate; forming a groove in the mounting surface of the base plate so as to be located outside the pad assembly; applying solder resist ink to a portion of the mounting surface of the bottom plate that is located outside the groove, thereby forming a solder resist ink layer including a first ink layer located outside the groove and a second ink layer located within the groove; providing an LED chip and connecting the LED chip to the pad assembly; A method for manufacturing a light emitting substrate is provided, comprising:

[0006] According to a second aspect of the present invention, a bottom plate having a mounting surface; a pad assembly attached to the mounting surface of the base plate; a solder resist ink layer provided on the mounting surface of the bottom plate; a groove formed on the mounting surface of the bottom plate so as to be located outside the pad assembly; an LED chip connected to the pad assembly; Including, The solder resist ink layer includes a first ink layer located outside the groove and a second ink layer located within the groove. Effect of the Invention

[0007] The TFT backplane of the embodiment of the present invention is provided with a pressure-sensitive transistor, so that when the first pressure-sensitive material layer is subjected to pressure, a low potential is formed in the second conductive layer located on one side of the first pressure-sensitive material layer, and a high potential is formed in the second grid located on the other side of the first pressure-sensitive material layer, the pressure-sensitive transistor is turned on to generate an electric current, and the pressure signal is converted into an electrical signal. By monitoring the magnitude of the electrical signal, the pressure change received by the TFT backplane during the LED transfer compression process can be monitored in real time, thereby avoiding a short circuit of the internal circuit caused by the backplane being subjected to too high pressure, and improving the transfer efficiency. [Brief description of the drawings]

[0008] In order to more clearly describe the technical means in the embodiments of the present invention, the drawings necessary for describing the embodiments are briefly described below. The drawings shown below are only some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative efforts.

[0009] For a more complete understanding of the present invention and its advantageous advantages, reference is now made to the following description, in which like reference numerals represent like parts, and in which:

[0010] [Figure 1] 4 is a flowchart of a method for manufacturing a light emitting substrate according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic diagram of step 100 of the manufacturing method of FIG. 1. [Diagram 3] 3 is a schematic cross-sectional view of the structure in FIG. 2 taken along the AA direction. [Figure 4] FIG. 2 is a schematic diagram of step 200 of the manufacturing method of FIG. 1. [Diagram 5] 5 is a schematic cross-sectional view of the structure in FIG. 4 taken along the BB direction. [Figure 6] FIG. 2 is a schematic diagram of step 300 of the manufacturing method of FIG. 1. [Figure 7] FIG. 7 is a schematic cross-sectional view of the structure in FIG. 6 taken along the CC direction. [Figure 8] 4 is a schematic diagram of step 400 of the manufacturing method of FIG. 1 and a schematic diagram of a light emitting substrate according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The following will clearly and completely describe the technical means in the embodiments of the present invention through the drawings related to the embodiments of the present invention. The following embodiments are only a part of the embodiments of the present invention, and are not all of the embodiments. Based on the embodiments of the present invention, other embodiments that can be obtained by those skilled in the art without creative efforts are all included in the protection scope of the present invention.

[0012] 1 is a flow chart of a method for manufacturing a light emitting substrate according to an embodiment of the present invention. According to an embodiment of the present invention, there is provided a method for manufacturing a light emitting substrate, including the following steps 100 to 400.

[0013] In step 100, a first substrate is provided that includes a base plate and a pad assembly attached to a mounting surface of the base plate.

[0014] Please refer to Figures 2 and 3. Figure 2 is a schematic diagram of step 100 of the manufacturing method of Figure 1. Figure 3 is a schematic cross-sectional view of the structure in Figure 2 along the AA direction. The pad assembly 12 may include a first pad 121 and a second pad 122 spaced apart from each other. As can be seen, one of the first pad 121 and the second pad 122 can be welded to the positive pole of the LED chip 30, and the other of the first pad 121 and the second pad 122 can be welded to the negative pole of the LED chip 30.

[0015] 2, the first substrate 20 may further include a conductor 14 provided on the mounting surface of the bottom plate 11. The conductor 14 is connected to the pad assembly 12. Specifically, the first pad 121 and the second pad 122 in the pad assembly 12 are connected to two different conductors 14, respectively.

[0016] For example, the material of the bottom plate 11 may be resin, glass, etc. The material of both the first pad 121 and the second pad 122 may be metal, for example, copper (Cu).

[0017] In step 200, a groove is formed in the mounting surface of the base plate so as to be located outside the pad assembly.

[0018] For example, the "step of forming a groove 115 on the mounting surface of the bottom plate 11" may specifically include the step of irradiating the mounting surface of the bottom plate 11 with a laser so that the groove 115 is formed on the mounting surface of the bottom plate 11.

[0019] Please refer to Figures 4 and 5. Figure 4 is a schematic diagram of step 200 of the manufacturing method of Figure 1. Figure 5 is a schematic cross-sectional view of the structure in Figure 4 along the BB direction. When the pad assembly 12 includes a first pad 121 and a second pad 122 spaced apart from each other, the distance a between the inner edge of the groove 115 and the outer edge of the first pad 121 may be set to 5 μm to 15 μm (e.g., 5 μm, 7 μm, 9 μm, 10 μm, 12 μm, 14 μm, 15 μm, etc.), and the distance b between the inner edge of the groove 115 and the outer edge of the second pad 122 may be set to 5 μm to 15 μm (e.g., 5 μm, 7 μm, 9 μm, 10 μm, 12 μm, 14 μm, 15 μm, etc.). As can be seen, the groove 115 can be formed at a position close to the pad assembly 12 due to the high accuracy of the laser processing.

[0020] 4, the groove 115 is interrupted at the location of the conductor 14 to allow the conductor 14 to escape, that is, the groove 115 is a non-closed structure.

[0021] Illustratively, groove 115 may be generally rectangular.

[0022] Illustratively, the material of the conductor 14 may be a metal, such as copper (Cu).

[0023] In step 300, a solder resist ink is applied to a portion of the mounting surface of the bottom plate that is located outside the groove, thereby forming a solder resist ink layer that includes a first ink layer located outside the groove and a second ink layer located within the groove.

[0024] Please refer to Figures 6 and 7. Figure 6 is a schematic diagram of step 300 of the manufacturing method of Figure 1. Figure 7 is a schematic cross-sectional view along the CC direction of the structure in Figure 6. The "step of applying solder resist ink to a location located outside the groove on the mounting surface of the bottom plate" may specifically include a step of applying solder resist ink to a location located within a range of more than 0 and less than 5 μm (e.g., 0.5 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, etc.) from the outer edge of the groove 115 on the mounting surface. As can be understood, since the ink has fluidity, the solder resist ink applied outside the groove 115 automatically flows in the direction in which the groove 115 is located, enters the groove 115, and hardens to form the second ink layer 132 located inside the groove 115, and the solder resist ink located on the surface of the bottom plate 11 outside the groove 115 hardens to form the first ink layer 131.

[0025] As can be appreciated, the second ink layer 132 may completely fill the grooves 115, i.e., the thickness of the second ink layer 132 is equal to the depth of the grooves 115 (FIG. 7). Alternatively, the second ink layer 132 may not completely fill the grooves 115, i.e., the thickness of the second ink layer 132 is less than the depth of the grooves 115.

[0026] For example, the solder resist ink can be applied from the outside of the grooves 115 by inkjet printing or screen printing.

[0027] As can be seen, the action of the solder resist ink is as follows. 1. As a solder resist layer, it can prevent short circuits caused by bridging during the welding process. 2. As a protective layer, it protects the circuit in the bottom plate 11 and also provides an insulating effect. 3. A pigment may be added to the solder resist ink layer 13. The effects of adding different pigments are different. For example, by adding a white pigment to the solder resist ink layer 13, a white ink layer is formed on the solder resist ink layer 13. Since the white ink layer has high reflectivity, it is applied to backlight products to improve the light source utilization rate of liquid crystal display devices. Alternatively, by adding a black pigment to the solder resist ink layer 13, a black ink layer is formed on the solder resist ink layer 13. Since the black ink layer has high contrast, it is applied to direct display products to improve the contrast and display effect of LED display products.

[0028] Currently, LED backlight products have higher and higher requirements for reflectivity. In LED backlight products, in order to ensure that the reflectivity of the outer white solder resist ink layer 13 is 90% or more, the distance between the inner edge of the white solder resist ink layer 13 and the outer edge of the pad should be less than 50 μm. That is, the closer the white solder resist ink layer 13 is to the pad position, the better so that it covers the entire area around the pad as much as possible. However, due to the limitations of the conventional ink printing process, the maximum ink application accuracy that can be achieved at present is 75 μm. If the distance between the inner edge of the solder resist ink layer and the outer edge of the pad is less than 75 μm, the phenomenon of ink spilling onto the pad surface (i.e., the solder resist ink overflows onto the pad) will occur, resulting in poor welding or difficulty in welding when welding the pad and the LED chip, and the current requirements for ink application accuracy of LED backlight products will not be met. As can be seen, the higher the ink application accuracy, the smaller the distance between the inner edge of the ink and the outer edge of the pad, and the higher the reflectance of the LED backlight product having the white solder resist ink layer 13, which can meet the needs of the specification design of high-end products. In the embodiment of the present invention, by forming the groove 115 at the portion of the bottom plate 11 located outside the pad assembly 12, the solder resist ink applied outside the groove 115 is guided by the groove 115 and automatically flows into the groove 115, thereby forming the second ink layer 132 close to the pad assembly 12. Due to the high manufacturing accuracy of the process such as laser processing, it is possible to form the groove 115 as close as possible to the pad assembly 12. Currently, the distance between the inner edge of the groove 115 and the outer edge of the pad assembly 12 can be 5 μm to 15 μm. Since the second ink layer 132 is provided within the groove 115, the inner edge of the groove 115 becomes the inner edge of the solder resist ink layer 13, that is, the distance (ink application accuracy) between the inner edge of the solder resist ink layer 13 and the outer edge of the pad assembly 12 is 5 μm to 15 μm. This significantly improves the ink application accuracy of the LED backlight product, making it possible to achieve a reflectance of 90% or more for the LED backlight product.In addition, the groove 115 has a high capacity and can receive the solder resist ink flowing from the application position onto the pad assembly 12, thereby preventing the solder resist ink from overflowing onto the pad assembly 12, thereby preventing poor welding or failed welding.

[0029] Furthermore, the pitch (pitch; distance between pixels) of LED direct display products is becoming smaller. This means that the requirements for the application accuracy of the solder resist ink are becoming higher, and the distance between the solder resist ink and the pads is becoming closer. If the pitch of the LED direct display product is 0.6 mm or less, the current black solder resist ink printing process cannot meet the accuracy requirements, so BM (black matrix) can only be used instead. In the manufacturing method of the light emitting substrate according to the embodiment of the present invention, by forming the groove 115 at the portion of the bottom plate 11 located outside the pad assembly 12, the guide effect of the groove 115 on the solder resist ink and the advantage that the process of forming the groove 115 itself has high accuracy can be utilized to significantly shorten the distance between the inner edge of the solder resist ink layer 13 and the outer edge of the pad assembly 12 (5 μm to 15 μm), thereby realizing high ink application accuracy. In the LED direct display product having the black solder resist ink layer 13, the contrast of the LED direct display product is significantly improved, and therefore the display effect is improved. Additionally, the groove 115 contains any overflowing solder resist ink, thereby preventing poor or failed welds caused by the solder resist ink overflowing onto the pad assembly 12 .

[0030] Illustratively, the width w of groove 115 may be 30 μm to 60 μm (e.g., 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, etc.), and the depth h of groove 115 may be 15 μm to 45 μm (e.g., 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, etc.).

[0031] For example, the thickness of the first ink layer 131 may be 15 μm to 45 μm (e.g., 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, etc.), and the thickness of the second ink layer 132 may be 15 μm to 45 μm (e.g., 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, etc.).

[0032] In step 400, an LED chip is provided and the LED chip is connected to a pad assembly.

[0033] 8 is a schematic diagram of step 400 of the manufacturing method of FIG. 1 and a schematic diagram of a light emitting substrate according to an embodiment of the present invention. The LED chip 30 and the pad assembly 12 can be connected by welding.

[0034] Exemplarily, the LED chip 30 may have a positive electrode and a negative electrode, with the positive electrode being connected to the first pad 121 and the negative electrode being connected to the second pad 122.

[0035] As described above, in the manufacturing method of the light emitting substrate according to the embodiment of the present invention, by forming the groove 115 in the bottom plate 11, the solder resist ink applied outside the groove 115 is guided by the groove 115 and automatically flows into the groove 115, thereby shortening the distance between the solder resist ink layer 13 and the pad assembly 12 and improving the application accuracy of the solder resist ink layer. In addition, it is ensured that the solder resist ink layer 13 has high application accuracy, and since the groove 115 has the ability to accommodate overflowing ink, the occurrence of poor welding or failed welding caused by the solder resist ink overflowing onto the pad assembly 12 is avoided. Furthermore, the manufacturing method of the present invention is simple, easy to implement, and has low production costs.

[0036] Please refer to Figs. 6 to 8. According to an embodiment of the present invention, a light emitting substrate 100 is further provided. The light emitting substrate 100 can be manufactured by the manufacturing method of the light emitting substrate 100 according to any of the above embodiments. The light emitting substrate 100 may include a bottom plate 11, a pad assembly 12, a solder resist ink layer 13, and an LED chip 30. The bottom plate 11 has a mounting surface, the pad assembly 12 is mounted on the mounting surface of the bottom plate 11, the solder resist ink layer 13 is provided on the mounting surface of the bottom plate 11, and a groove 115 is formed on the mounting surface of the bottom plate 11 so as to be located outside the pad assembly 12. The solder resist ink layer 13 includes a first ink layer 131 located outside the groove 115 and a second ink layer 132 located within the groove 115. The LED chip 30 and the pad assembly 12 are connected.

[0037] 6 and 7, the pad assembly 12 may include a first pad 121 and a second pad 122 spaced apart from each other. A distance a between an inner edge of the groove 115 and an outer edge of the first pad 121 is 5 μm to 15 μm (e.g., 5 μm, 7 μm, 9 μm, 10 μm, 12 μm, 14 μm, 15 μm, etc.), and a distance b between the inner edge of the groove 115 and an outer edge of the second pad 122 is 5 μm to 15 μm (e.g., 5 μm, 7 μm, 9 μm, 10 μm, 12 μm, 14 μm, 15 μm, etc.).

[0038] 4 and 6, the light emitting substrate 100 may further include a conductive wire 14 attached to the mounting surface of the bottom plate 11. The conductive wire 14 and the pad assembly 12 are connected to each other. The groove 115 is interrupted at the position of the conductive wire 14 to allow the conductive wire 14 to escape. Specifically, the first pad 121 and the second pad 122 of the pad assembly 12 are connected to two different conductive wires 14, respectively.

[0039] Illustratively, the width w of groove 115 may be 30 μm to 60 μm (e.g., 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, etc.), and the depth h of groove 115 may be 15 μm to 45 μm (e.g., 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, etc.).

[0040] For example, the thickness of the first ink layer 131 may be 15 μm to 45 μm (e.g., 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, etc.), and the thickness of the second ink layer 132 may be 15 μm to 45 μm (e.g., 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, etc.).

[0041] As can be appreciated, the grooves 115 may be completely filled by the second ink layer 132, i.e., the thickness of the second ink layer 132 is equal to the depth of the grooves 115 (FIG. 7). Alternatively, the grooves 115 may not be completely filled by the second ink layer 132, i.e., the thickness of the second ink layer 132 is less than the depth of the grooves 115.

[0042] For example, the material of the bottom plate 11 may be resin or glass, etc. The material of the first pad 121 and the second pad 122 may be metal, for example, copper (Cu). The material of the conductive wire 14 may be metal, for example, copper (Cu).

[0043] Illustratively, groove 115 may be generally rectangular.

[0044] Illustratively, the LED chip 30 and the pad assembly 12 may be connected by welding.

[0045] Exemplarily, the LED chip 30 may have a positive electrode and a negative electrode, the positive electrode being connected to the first pad 121 and the negative electrode being connected to the second pad 122.

[0046] The light emitting substrate 100 may be a backlight product, that is, it may be applied to a liquid crystal display device to provide a light source for a liquid crystal panel.

[0047] The light-emitting substrate 100 may be a direct display product, that is, it can be directly used as a display device.

[0048] In the light emitting substrate 100 according to the embodiment of the present invention, the groove 115 is formed at the portion of the bottom plate 11 located outside the pad assembly 12, so that the inner edge of the solder resist ink layer 13 can extend to the inner edge of the groove 115. Since the process of forming the groove 115 is highly accurate, that is, the inner edge of the groove 115 can be as close as possible to the pad assembly 12, the distance between the inner edge of the solder resist ink layer 13 and the outer edge of the pad assembly 12 is shortened, and the application accuracy of the solder resist ink layer 13 is improved. In addition, the solder resist ink layer 13 is guaranteed to have high application accuracy, and since the groove 115 has the ability to accommodate overflowing ink, the occurrence of poor welding or failure of welding caused by the solder resist ink overflowing onto the pad assembly 12 is avoided. In addition, the light emitting substrate 100 has a simple structure, is easy to manufacture, and has a low production cost. Furthermore, because the application precision of the solder resist ink layer 13 on the light emitting substrate 100 is high, when the light emitting substrate 100 is used as a backlight product (i.e., when the solder resist ink layer 13 is a white ink), it can improve the reflectance of the backlight product. When the light emitting substrate 100 is used as a direct display product (i.e., when the solder resist ink layer 13 is a black ink), it can improve the contrast of the direct display product and improve its display effect. Therefore, this light emitting substrate 100 can meet the specification design needs of various high-end products.

[0049] The above is a detailed description of the light emitting substrate and the manufacturing method thereof according to the embodiment of the present invention. In this specification, the principle and embodiment of the present invention are described using specific examples, but the description of the above examples is only intended to help understand the present invention. In addition, those skilled in the art can change the specific embodiment and the scope of use based on the concept of the present invention. Therefore, the contents of this specification should not be understood as a limitation on the present invention.

Claims

1. A method for manufacturing a light emitting substrate, comprising the steps of: providing a first substrate including a base plate and a pad assembly attached to a mounting surface of the base plate; forming a groove in the mounting surface of the base plate so as to be located outside the pad assembly; applying solder resist ink to a portion of the mounting surface of the bottom plate that is located outside the groove, thereby forming a solder resist ink layer including a first ink layer located outside the groove and a second ink layer located within the groove; providing an LED chip and connecting the LED chip to the pad assembly; Including, A method for manufacturing a light emitting substrate, wherein the groove has a width of 30 μm to 60 μm and a depth of 15 μm to 45 μm.

2. The method for manufacturing a light-emitting substrate as described in claim 1 , wherein the step of forming the groove on the mounting surface of the bottom plate includes a step of irradiating the mounting surface of the bottom plate with a laser so that the groove is formed on the mounting surface of the bottom plate.

3. the first substrate further includes a conductor provided on the mounting surface of the bottom plate, The electrical leads are connected to the pad assembly; The method for manufacturing a light emitting substrate according to claim 1 , wherein the groove is interrupted at a position of the conductive wire.

4. The pad assembly includes a first pad and a second pad spaced apart from each other; the distance between the inner edge of the groove and the outer edge of the first pad is between 5 μm and 15 μm; The method for manufacturing a light emitting substrate according to claim 1 , wherein a distance between an inner edge of the groove and an outer edge of the second pad is 5 μm to 15 μm.

5. The method for manufacturing a light-emitting substrate as described in claim 1, wherein the step of applying the solder resist ink to a location located outside the groove on the mounting surface of the bottom plate includes a step of applying the solder resist ink to a location located within a range of more than 0 and less than 5 μm from the outer edge of the groove on the mounting surface.

6. The method for manufacturing a light emitting substrate according to claim 1 , wherein the step of connecting the LED chip and the pad assembly includes the step of connecting the LED chip and the pad assembly by welding.

7. The method for manufacturing a light-emitting substrate as described in claim 1, wherein the step of applying solder resist ink to a location on the mounting surface of the bottom plate that is located outside the groove includes a step of applying the solder resist ink from outside the groove by inkjet printing or screen printing.

8. The method for manufacturing a light emitting substrate according to claim 4 , wherein the first pad and the second pad are both made of a metal.

9. a bottom plate having a mounting surface; a pad assembly attached to the mounting surface of the base plate; a solder resist ink layer provided on the mounting surface of the bottom plate; a groove formed on the mounting surface of the bottom plate so as to be located outside the pad assembly; an LED chip connected to the pad assembly; Including, the solder resist ink layer includes a first ink layer located outside the groove and a second ink layer located within the groove; A light emitting substrate, wherein the width of the groove is 30 μm to 60 μm and the depth of the groove is 15 μm to 45 μm.

10. The light emitting substrate further includes a conductive wire provided on the mounting surface of the bottom plate, The electrical leads are connected to the pad assembly; The light-emitting substrate according to claim 9 , wherein the groove is interrupted at the location of the conductive wire.

11. The pad assembly includes a first pad and a second pad spaced apart from each other; the distance between the inner edge of the groove and the outer edge of the first pad is between 5 μm and 15 μm; The light emitting substrate of claim 9 , wherein the distance between the inner edge of the groove and the outer edge of the second pad is 5 μm to 15 μm.

12. The light emitting substrate according to claim 9, wherein the first ink layer has a thickness of 15 μm to 45 μm.

13. The light emitting substrate according to claim 9, wherein the second ink layer has a thickness of 15 μm to 45 μm.

14. The light emitting substrate according to claim 9 , wherein the LED chip and the pad assembly are connected by welding.

15. The light-emitting substrate according to claim 11 , wherein the first pad and the second pad are both made of a metal.

16. The light emitting substrate according to claim 9 , wherein the material of the bottom plate is resin or glass.

Images