Method for manufacturing a light emitting device

Abstract

The present invention discloses a method for manufacturing a light-emitting device. The method comprises the following steps: placing a plurality of light-emitting elements on a circuit substrate; forming a first light-absorbing adhesive between each light-emitting element, wherein the light-emitting element comprises a first light-emitting element, and the first light-absorbing adhesive has a first portion surrounding the first light-emitting element; performing an etching process to remove the first portion of the first light-absorbing adhesive; replacing the first light-emitting element with a second light-emitting element; pressing the second light-absorbing adhesive toward the first light-absorbing adhesive so that at least a portion of the second light-absorbing adhesive surrounds the second light-emitting element and covers both sides of the light-emitting element.

Description

Technical Field

[0001] The invention relates to a method for manufacturing a light emitting device. Background Art

[0002] The light emitting diode display device has a plurality of light emitting diodes (LEDs). The light emitting diodes have the advantages of high resolution, power saving, and long life. In the current production process of micro-LED display devices, a large number of LEDs need to be transferred to another substrate through mass transfer and then packaged. In order to improve the yield rate of the display device, after packaging, the packaging will be tested to remove the failed micro-LEDs, and then packaged. However, if the packaging is done by dispensing glue, it will cause the disadvantage of poor flatness, and if transparent glue is used, it will also cause white spots to appear on the display screen. Summary of the invention

[0003] The invention provides a method for manufacturing a light emitting device, which has good flatness and can avoid white spots on a display screen.

[0004] A method for manufacturing a light-emitting device according to an embodiment of the present invention includes the following steps. A plurality of light-emitting elements are placed on a circuit substrate. A first light-absorbing adhesive is formed between each light-emitting element, wherein the light-emitting element includes a first light-emitting element, and the first light-absorbing adhesive has a first portion surrounding the first light-emitting element. An etching process is performed to remove the first portion of the first light-absorbing adhesive. The first light-emitting element is replaced with a second light-emitting element. The second light-absorbing adhesive is pressed toward the first light-absorbing adhesive so that at least a portion of the second light-absorbing adhesive surrounds the second light-emitting element and covers both sides of the light-emitting element.

[0005] Based on the above, an etching process is performed to remove the first portion of the first light-absorbing adhesive material, and the second light-absorbing adhesive material is pressed toward the first light-absorbing adhesive material, so that at least a portion of the second light-absorbing adhesive material surrounds the second light-emitting element and covers both sides of the light-emitting element. This can improve the flatness of the light-emitting device, and because both the first light-absorbing adhesive material and the second light-absorbing adhesive material are light-absorbing materials, white spots on the display screen can be avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The following detailed description and the accompanying drawings will provide a glimpse into the various aspects of the present invention. It should be noted that the features in the drawings are not drawn to scale in accordance with standard practice in the industry. In fact, the dimensions of the features may be increased or decreased as desired to facilitate clarity of discussion.

[0007] Figures 1 to 8 is a schematic diagram of a method for manufacturing a light emitting device according to an embodiment of the present invention;

[0008] Figures 9 to 15 is a schematic diagram of a method for manufacturing a light emitting device according to another embodiment of the present invention.

[0009] Explanation of symbols

[0010] 10. 10a: Light-emitting device

[0011] 100: Circuit board

[0012] 102: Light emitting element

[0013] 102A: first light emitting element

[0014] 102B: Second light emitting element

[0015] 104: The first light-absorbing adhesive

[0016] 104A: Part 1

[0017] 106: Second light-absorbing adhesive

[0018] 108: Second light-transmitting plastic material

[0019] 110: The first light-transmitting adhesive

[0020] 110R: concave part

[0021] 112: Mould

[0022] 1000: Etching process

[0023] 1002:Lamination

[0024] 1004: Plasma production process

[0025] 1006:Laser production process

[0026] 1008: Etching process

[0027] L: Dashed line

[0028] MK:Mask

[0029] OP: Opening DETAILED DESCRIPTION

[0030] Figures 1 to 8 This is a method for manufacturing a light emitting device 10 according to an embodiment of the present invention. Figure 1 , a plurality of light emitting elements 102 are placed on the circuit substrate 100, and a first light absorbing adhesive material 104 is formed between each light emitting element 102. The circuit substrate 100 may have a plurality of pads (not shown), and the light emitting element 102 is flip-chip bonded to the circuit substrate 100. The light emitting element 102 may display different colors, such as red, green, and blue.

[0031] In this embodiment, the light emitting elements 102 are tested under the packaging of a single layer of glue (e.g., the first light absorbing glue material 104) to confirm that each light emitting element 102 has the expected light emitting state, and to repair the damaged light emitting element 102. For example, the light emitting element 102 includes a first light emitting element 102A, and the first light absorbing glue material 104 has a first portion 104A surrounding the first light emitting element 102A. In one embodiment, after testing the first light emitting element 102A, if it is considered that it does not have the expected light emitting state, then Figure 2 As shown, an etching process 1000 is performed to remove the first portion 104A of the first light absorbing glue 104. In this embodiment, the etching process 1000 is a plasma process. For example, the etching process 1000 is an atmospheric pressure (AP) plasma process, and uses the opening of the mask MK to expose the first light emitting element 102A and cover the remaining light emitting elements 102.

[0032] In one embodiment, the step of removing the first portion 104A of the first light absorbing adhesive material 104 allows the first light absorbing adhesive material 104 to have an opening OP (eg, Figure 3 As shown), the first light-emitting element 102A can be easily taken out.

[0033] Next refer to Figure 4 , the first light emitting element 102A is replaced by the second light emitting element 102B, and the color displayed by the second light emitting element 102B is the same as the color displayed by the first light emitting element 102A. The second light absorbing adhesive material 106 is pressed toward the first light absorbing adhesive material 104, so that at least part of the second light absorbing adhesive material 106 surrounds the second light emitting element 102B and covers both sides of the light emitting element 102 (such as Figure 5 For example, in one embodiment, the circuit substrate 100 can be placed on the mold 112, and the second light absorbing adhesive material 106 can be pressed toward the first light absorbing adhesive material 104 by laminating 1002. In this way, the flatness of the light emitting device 10 can be improved, for example, the top surface flatness can be improved, and since both the first light absorbing adhesive material 104 and the second light absorbing adhesive material 106 are light absorbing materials, white spots on the display screen can be avoided.

[0034] Next, please refer to Figure 5 In one embodiment, the step of pressing the second light absorbing adhesive material 106 against the first light absorbing adhesive material 104 enables the second light absorbing adhesive material 106 to fill the opening OP. For example, the second light absorbing adhesive material 106 also covers the first light absorbing adhesive material 104. For the sake of clarity, Figure 5 A dotted line L is shown in FIG. 1 , the second light absorbing adhesive material 106 is located above the dotted line L, and the first light absorbing adhesive material 104 is located below the dotted line L.

[0035] In one embodiment, the optical coefficient of the second light absorbing adhesive 106 after curing is the same as the optical coefficient of the first light absorbing adhesive 104 after curing. The optical coefficient referred to here is, for example, optical density (OD) and / or absorbance. In one embodiment, the material of the second light absorbing adhesive 106 is the same as the material of the first light absorbing adhesive 104.

[0036] Please refer to Figure 6 , remove the top of the second light absorbing glue material 106 to expose the light emitting element 102 and the second light emitting element 102B. In one embodiment, the top of the second light absorbing glue material 106 is removed by using a plasma manufacturing process 1004 .

[0037] Please refer to Figure 7 After removing the top of the second light-absorbing glue 106, a second light-transmitting glue 108 is formed on the first light-absorbing glue 104, the second light-absorbing glue 106, the light-emitting element 102 and the second light-emitting element 102B. The second light-transmitting glue 108 covers the light-emitting element 102 and the second light-emitting element 102B. The material of the second light-transmitting glue 108 is, for example, a photoresist material, epoxy resin, silicone resin, polymethyl methacrylate (PMMA) or other suitable light-transmitting materials, so that the light emitted by the light-emitting element 102 and the second light-emitting element 102B can be transmitted. In one embodiment, the second light-transmitting glue 108 can be formed by lamination.

[0038] Figures 8 to 15 This is a method for manufacturing a light emitting device 10a according to another embodiment of the present invention. Figure 8 In some embodiments, the light emitting device 10a is repaired after being packaged with multiple layers of adhesive. For example, a plurality of light emitting elements 102 are placed on a circuit substrate 100, a first light absorbing adhesive material 104 is formed between each light emitting element 102, the light emitting element 102 includes a first light emitting element 102A, the first light absorbing adhesive material 104 has a first portion 104A surrounding the first light emitting element 102A, and then a first light transmissive adhesive material 110 is formed on the first light absorbing adhesive material 104. In this embodiment, the light emitting element 102 is tested under the packaging of multiple layers of adhesive (e.g., the first light absorbing adhesive material 104, the first light transmissive adhesive material 110). The material of the first light transmissive adhesive material 110 is, for example, a photoresist material, epoxy resin, silicone resin, polymethyl methacrylate (PMMA) or other suitable light transmissive materials, so that the light emitted by the light emitting element 102 and the first light emitting element 102A can be transmitted.

[0039] Please refer to Fig. 9, at least a portion of the first light-transmitting adhesive material 110 is removed by a laser process 1006. The laser used in the laser process 1006 is, for example, a UV laser. Fig.10 , an etching process 1008 is performed to remove the first portion 104A of the first light absorbing glue material 104. That is, in this embodiment, before the etching process 1008 is performed, the first light-transmitting glue material 110 is formed on the first light absorbing glue material 104 (see Figure 8 ), and remove at least a portion of the first light-transmitting adhesive material 110 by laser processing 1006 (see Fig. 9 ). In one embodiment, after the laser manufacturing process 1006, the first light-transmitting adhesive material 110 has a recess 110R, and the recess 110R is located at the top of the first light-emitting element 102A. Since the circuit substrate 100 is still covered by the first light-absorbing adhesive material 104 during the execution of the laser manufacturing process 1006, the circuit substrate 100 can be protected by the first light-absorbing adhesive material 104 and avoid being damaged by the laser of the laser manufacturing process 1006, so that the electrical properties of the circuit substrate 100 can be maintained, and its reliability is good. In one embodiment, the etching manufacturing process 1008 is a plasma manufacturing process. In this embodiment, the etching manufacturing process 1008 also includes removing the bottom of the first light-transmitting adhesive material 110.

[0040] In one embodiment, the step of removing the first portion 104A of the first light absorbing adhesive material 104 enables the first light absorbing adhesive material 104 to have an opening OP exposing the circuit substrate 100 , thereby making it easier to remove the first light emitting element 102A.

[0041] Next, please refer to Fig.11 , the first light emitting element 102A is replaced by the second light emitting element 102B, and the color displayed by the second light emitting element 102B is the same as the color displayed by the first light emitting element 102A.

[0042] Please refer to Fig.12 and Fig.13 , the second light absorbing adhesive material 106 is pressed toward the first light absorbing adhesive material 104, so that at least a portion of the second light absorbing adhesive material 106 surrounds the second light emitting element 102B and covers both sides of the light emitting element 102 (see Fig.13 ), for the sake of clarity, Fig.13 The dotted line L is shown in FIG. 1 , the second light absorbing adhesive material 106 is located above the dotted line L, and the first light absorbing adhesive material 104 is located below the dotted line L. In one embodiment, the circuit substrate 100 can be placed on the mold 112 (see FIG. 1 ). Fig.12 ), the second light absorbing adhesive material 106 is pressed toward the first light absorbing adhesive material 104 by laminating 1002. In this way, the flatness of the light emitting device 10a can be improved, for example, the top surface flatness can be improved, and since both the first light absorbing adhesive material 104 and the second light absorbing adhesive material 106 are light absorbing materials, white spots on the display screen can be avoided.

[0043] In one embodiment, the step of pressing the second light absorbing adhesive material 106 toward the first light absorbing adhesive material 104 enables the second light absorbing adhesive material 106 to fill up the opening OP. For example, the second light absorbing adhesive material 106 also covers the first light absorbing adhesive material 104 .

[0044] Please refer to Fig.14 , remove the top of the second light absorbing glue material 106 to expose the light emitting element 102 and the second light emitting element 102B. In one embodiment, the top of the second light absorbing glue material 106 is removed by using a plasma manufacturing process 1004 .

[0045] Please refer to Fig.15 After removing the top of the second light-absorbing adhesive material 106, a second light-transmitting adhesive material 108 is formed on the first light-absorbing adhesive material 104, the second light-absorbing adhesive material 106, the light-emitting element 102 and the second light-emitting element 102B. The second light-transmitting adhesive material 108 covers the light-emitting element 102 and the second light-emitting element 102B. In one embodiment, the second light-transmitting adhesive material 108 can be formed by lamination.

[0046] In summary, the light-emitting device of the present embodiment utilizes an etching manufacturing process to remove a first portion of the first light-absorbing adhesive material, and press the second light-absorbing adhesive material toward the first light-absorbing adhesive material, so that at least a portion of the second light-absorbing adhesive material surrounds the second light-emitting element and covers both sides of the light-emitting element. This can improve the flatness of the light-emitting device, and because both the first light-absorbing adhesive material and the second light-absorbing adhesive material are light-absorbing materials, white spots on the display screen can be avoided.

Claims

1. A method for manufacturing a light emitting device, comprising: Placing a plurality of light emitting elements on a circuit substrate; Forming a first light-absorbing adhesive material between each of the light-emitting elements, wherein the light-emitting elements include a first light-emitting element, and the first light-absorbing adhesive material has a first portion surrounding the first light-emitting element; Performing an etching process to remove the first portion of the first light absorbing glue; replacing the first light emitting element with a second light emitting element; and The second light-absorbing adhesive material is pressed toward the first light-absorbing adhesive material, so that at least a portion of the second light-absorbing adhesive material surrounds the second light-emitting element and covers both sides of the light-emitting element. Wherein, the manufacturing method further comprises: Before performing the etching process, forming a first light-transmitting adhesive material on the first light-absorbing adhesive material; and At least a portion of the first light-transmitting adhesive is removed by a laser process. 2 . The manufacturing method as claimed in claim 1 , wherein an optical coefficient of the second light-absorbing adhesive material after curing is the same as an optical coefficient of the first light-absorbing adhesive material after curing. 3 . The manufacturing method as claimed in claim 1 , wherein a material of the second light-absorbing adhesive is the same as a material of the first light-absorbing adhesive. 4 . The manufacturing method as claimed in claim 1 , wherein after the laser manufacturing process, the first light-transmitting adhesive material has a concave portion, and the concave portion is located on the top of the first light-emitting element.

5. The manufacturing method as claimed in claim 1, wherein the etching process further comprises: The bottom of the first light-transmitting adhesive is removed.

6. The manufacturing method according to claim 1, further comprising: The top of the second light-absorbing adhesive is removed to expose the light-emitting elements and the second light-emitting element. 7 . The manufacturing method as claimed in claim 6 , wherein removing the top portion of the second light-absorbing adhesive material is performed by using a plasma manufacturing process.

8. The manufacturing method according to claim 6, further comprising: After removing the top of the second light-absorbing adhesive material, a second light-transmitting adhesive material is formed on the first light-absorbing adhesive material, the second light-absorbing adhesive material, the light-emitting elements and the second light-emitting element.

9. The manufacturing method as claimed in claim 1, wherein the etching process is a plasma process.

10. The manufacturing method as claimed in claim 1, wherein the step of removing the first portion of the first light absorbing adhesive material enables the first light absorbing adhesive material to have an opening exposing the circuit substrate, and the step of pressing the second light absorbing adhesive material toward the first light absorbing adhesive material enables the second light absorbing adhesive material to fill the opening. 11 . The manufacturing method as claimed in claim 10 , wherein the second light-absorbing adhesive material further covers the first light-absorbing adhesive material.

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