MIP grid glue filling dam surrounding technology and novel LED lamp bead

Abstract

The invention discloses an MIP grid glue filling dam surrounding technology and a novel LED lamp bead, and relates to the technical field of LED packaging, and the technology comprises the following steps: light-emitting chips are fixed on a substrate, the light-emitting chips and the substrate form a eutectic interface through a eutectic welding technology, the substrate comprises N units, and at least one group of light-emitting chips are fixed in each unit; curing the packaging glue on the surface of the substrate through a first molding process to form a bowl cup main body covering the light-emitting chip and the eutectic interface; performing depth-controlled cutting on the bowl cup main body, and forming grid-shaped grooves between adjacent units; the grid-shaped groove is filled with dark dam glue through a second mold pressing process, and a dam structure is formed after curing; mirror polishing is conducted on the surface filled with the box dam glue; the substrate is cut and formed, the LED lamp bead finished product with the packaging glue body evenly wrapped by the box dam structure on the periphery is obtained, the MIP light interference pain point can be effectively eliminated under the condition that the dispensing input is not increased, and the reliability is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of LED packaging, and more particularly to a MIP grid glue-filling dam process and a novel LED lamp bead. Background Art

[0002] MIP technology achieves high-density integration by dicing Mini / Micro LED wafers into single or multiple small chips and combining them with mass transfer technology. This technology utilizes precision processes including substrate eutectic reflow, fan-out packaging, dicing and sorting, and light splitting and mixing to ultimately form micro-modules with independent display units. Its core innovation lies in the three-dimensional integration of Micro LED chips and high-precision substrates through a fan-out packaging architecture. This significantly reduces the complexity of subsequent module testing and terminal assembly while maintaining chip-level packaging reliability.

[0003] Compared to COB integration technology, MIP achieves breakthrough innovation in structural design: using a flip-chip process to overcome the physical limitations of traditional RGB LED bracket injection molding, the package unit size is reduced from the traditional 1mm×1mm to less than 0.8mm. While this miniaturized architecture brings higher pixel density, it also creates unique optical challenges. Due to the reduced unit spacing after cutting, significant optical interference occurs between adjacent LEDs, which has become a key bottleneck restricting the application of MIP technology in large-scale display applications.

[0004] The current mainstream dam process uses a layered packaging strategy: first, a grid-like dam structure is constructed between the eutectic-bonded substrate units, followed by a molded encapsulation adhesive layer. Although this process can partially alleviate the optical interference problem, it still has technical limitations:

[0005] 1. Due to the difference in thermal expansion coefficient and humidity penetration, stress cracks are easily generated at the interface between the dam glue and the encapsulation glue, resulting in encapsulation failure.

[0006] 2. Special dispensing equipment is required to achieve the graphics of the dam glue, and the equipment investment and process verification costs are high.

[0007] 3. The height difference between the dam glue and the encapsulation glue limits the light field control.

[0008] Based on this, the present invention provides a MIP grid glue filling dam process and a new LED lamp bead. Summary of the Invention

[0009] In order to solve the problems raised in the above background technology, the present invention provides a MIP grid glue filling dam process and a new LED lamp bead, which can effectively eliminate the MIP light interference pain point without increasing the glue dispensing investment and improve reliability.

[0010] The present invention provides a MIP grid glue filling dam process and a new LED lamp bead adopting the following technical solutions:

[0011] A MIP grid glue filling dam process includes the following steps:

[0012] Step 1: Fix the light-emitting chip on the substrate and form a eutectic interface between the light-emitting chip and the substrate through a eutectic welding process, wherein the substrate comprises N units, and at least one group of light-emitting chips is fixed in each unit;

[0013] Step 2: solidify the encapsulation glue on the substrate surface through the first molding process to form a bowl-shaped body covering the light-emitting chip and the eutectic interface;

[0014] Step 3: Perform controlled depth cutting on the bowl body to form grid-like grooves between adjacent units;

[0015] Step 4: Fill the grid-shaped grooves with dark dam glue through a second molding process, and form a dam structure after curing;

[0016] Step 5: Mirror polish the surface after filling the dam glue;

[0017] Step 6: Cut and shape the substrate to obtain a finished LED lamp bead with the outer periphery of the packaging glue body evenly wrapped by the dam structure.

[0018] Preferably, in step 2, the packaging glue is made of a transparent material.

[0019] Preferably, in step 4, the dark dam glue is a black light-shielding material.

[0020] Preferably, in step 1, the welding temperature of the eutectic welding process is 200-400° C., and the welding pressure is 0.1-5 MPa.

[0021] Preferably, in step 2 and arrangement 4, the curing temperature of the molding process is 80-150° C., and the curing time is 10-120 minutes.

[0022] Preferably, in step 1, the depth of the controlled depth cutting is 30%-70% of the thickness of the substrate.

[0023] Preferably, in step five, the bowl body is flush with the top of the dam structure.

[0024] A novel LED lamp bead is prepared according to the above-mentioned MIP grid glue filling dam process.

[0025] In summary, the present invention has the following beneficial technical effects:

[0026] The sides of the lamp beads are fully wrapped and filled with dark dam glue to completely eliminate the problem of light crosstalk between adjacent units and ensure the directionality and color consistency of the light output. An integrated packaging glue bonding structure design is adopted to form a single packaging glue bonding interface between the light-emitting chip and the substrate. Compared with the traditional multi-point bonding method, the mechanical bonding strength and thermal stress aging resistance are significantly improved, and the device reliability is effectively improved. The grid-shaped groove secondary molding is adopted, and the precision dispensing equipment and customized molds required for the traditional dam process are abandoned. Through the coordination of standardized molds and two-time molding processes, the production line transformation cost is reduced and the process tolerance rate is improved. When water vapor invades, it preferentially diffuses along the substrate-dam glue interface and the dam glue-packaging glue composite interface, and the dense barrier effect of the dam glue blocks the water vapor from penetrating into the packaging glue. Compared with the traditional dispensing dam process, the failure risk in a humid and hot environment is reduced.

[0027] The above summary is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments and features described above, further aspects, embodiments and features of the present invention will be readily apparent by reference to the accompanying drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a flow chart of a MIP grid glue filling dam process according to an embodiment of the present invention;

[0029] Figure 2 (a) is a schematic diagram of the substrate, (b) is a schematic diagram of the substrate and the light-emitting chip, (c) is a schematic diagram of the side surface of the substrate, and (d) is a schematic diagram of the side surface of the substrate and the light-emitting chip;

[0030] Figure 3 (a) is a schematic diagram of the substrate, light-emitting chip, and bowl-cup body; (b) is a schematic diagram of the substrate, light-emitting chip, bowl-cup body, and grid-shaped grooves; (c) is a schematic diagram of the substrate, light-emitting chip, and bowl-cup body from the side; (d) is a schematic diagram of the substrate, light-emitting chip, bowl-cup body, and grid-shaped grooves from the side;

[0031] Figure 4 (a) is a schematic diagram of the substrate, light-emitting chip, bowl cup body and dam structure, (b) is a schematic diagram of the finished LED lamp bead, (c) is a schematic diagram of the substrate, light-emitting chip, bowl cup body and dam structure from the side, and (d) is a schematic diagram of the side of the finished LED lamp bead.

[0032] Explanation of the accompanying drawings: 1. substrate; 2. light-emitting chip; 3. bowl-cup body; 4. grid-shaped groove; 5. dam structure. DETAILED DESCRIPTION

[0033] The following is combined with Figures 1 to 4The present invention is described in further detail.

[0034] It should be noted that the drawings are schematic and not drawn to scale. For clarity and convenience, the relative sizes and proportions of parts shown in the drawings may be exaggerated or reduced in size. Any dimensions are illustrative only and are not intended to be limiting. Identical structures, elements, or components appearing in two or more drawings are denoted by the same reference numerals to indicate similar features.

[0035] Example 1

[0036] The embodiment of the present invention discloses a MIP grid glue filling dam process. Figures 1 to 4 A MIP grid glue filling dam process includes the following steps:

[0037] Step 1: Fix the light-emitting chip on the substrate 1 and form a eutectic interface between the light-emitting chip 2 and the substrate 1 through a eutectic welding process, wherein the substrate 1 includes N units, and at least one group of light-emitting chips 2 is fixed in each unit;

[0038] Step 2: solidify the encapsulation glue on the substrate surface through the first molding process to form a bowl-shaped body 3 covering the light-emitting chip 2 and the eutectic interface;

[0039] Step 3: Perform controlled depth cutting on the bowl body 3 to form grid-like grooves 4 between adjacent units;

[0040] Step 4: Fill the grid-shaped groove 4 with dark dam glue through a second molding process, and form a dam structure 5 after curing;

[0041] Step 5: Mirror polish the surface after filling the dam glue;

[0042] Step 6: Cut and shape the substrate 1 to obtain a finished LED lamp bead with the outer periphery of the packaging glue body evenly wrapped by the dam structure 5.

[0043] Specifically, the sides of the lamp beads are fully wrapped and filled with dark dam glue to completely eliminate the problem of light crosstalk between adjacent units, ensure the directionality and color consistency of the light output, and adopt an integrated packaging glue bonding structure design to form a single packaging glue bonding interface between the light-emitting chip 2 and the substrate 1. Compared with the traditional multi-point bonding method, the mechanical bonding strength and thermal stress aging resistance are significantly improved, and the device reliability is effectively improved. The grid-shaped groove 4 is used for secondary molding, and the precision dispensing equipment and customized molds required for the traditional dam process are abandoned. Through the coordination of standardized molds and two-time molding processes, the production line transformation cost is reduced and the process tolerance rate is improved. When water vapor invades, it diffuses preferentially along the substrate-dam glue interface and the dam glue-packaging glue composite interface, and the dense barrier effect of the dam glue blocks the water vapor from penetrating into the packaging glue. Compared with the traditional dispensing dam process, the failure risk in a humid and hot environment is reduced.

[0044] Specifically, in step 2, the packaging glue is made of transparent material.

[0045] Specifically, in step 4, the dark dam glue is a black light-shielding material.

[0046] Specifically, in step 1, the welding temperature of the eutectic welding process is 200-400° C., and the welding pressure is 0.1-5 MPa.

[0047] Specifically, in step 2 and arrangement 4, the curing temperature of the molding process is 80-150° C., and the curing time is 10-120 minutes.

[0048] Specifically, in step 1, the depth of the controlled cutting is 30%-70% of the thickness of the substrate 1 .

[0049] Specifically, in step five, the bowl body 3 is flush with the top of the dam structure 5 .

[0050] By adopting the MIP grid glue filling dam process of the present invention, the MIP light interference pain point can be effectively eliminated without increasing the glue dispensing investment, and the reliability can be improved.

[0051] Example 2

[0052] A novel LED lamp bead is prepared according to the above-mentioned MIP grid glue filling dam process.

[0053] The standard parts used in the present invention can all be purchased from the market, and special-shaped parts can be customized according to the description in the specification and the drawings. The specific connection methods of each part adopt conventional means such as mature bolts, rivets, welding, etc. in the existing technology. The machinery, parts and equipment all adopt conventional models in the existing technology, and the circuit connection adopts the conventional connection method in the existing technology, which will not be described in detail here.

[0054] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. "Multiple" means two or more, unless otherwise specifically defined.

[0055] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0056] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0057] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0058] In the drawings of the embodiments disclosed in the present invention, only the structures related to the embodiments disclosed in the present invention are involved. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present invention can be combined with each other.

[0059] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A MIP grid glue filling dam process, characterized in that: The following steps are involved: Step 1: Fixing the light-emitting chip on the substrate (1), and forming a eutectic interface between the light-emitting chip (2) and the substrate (1) through a eutectic welding process, wherein the substrate (1) comprises N units, and at least one group of light-emitting chips (2) is fixed in each unit; Step 2: solidifying the encapsulation glue on the substrate surface through a first molding process to form a bowl-shaped body (3) covering the light-emitting chip (2) and the eutectic interface; Step 3: cutting the bowl body (3) with controlled depth to form grid-like grooves (4) between adjacent units; Step 4: Fill the dark dam glue into the grid-shaped groove (4) through a second molding process, and form a dam structure (5) after solidification; Step 5: Mirror polish the surface after filling the dam glue; Step 6: Cut and shape the substrate (1) to obtain a finished LED lamp bead with the outer periphery of the packaging glue body uniformly wrapped by the surrounding dam structure (5).

2. The MIP grid glue filling dam process according to claim 1, characterized in that: In step 2, the encapsulating glue is a transparent material.

3. The MIP grid glue filling dam process according to claim 1, characterized in that: In step 4, the dark dam glue is a black light-shielding material.

4. The MIP grid glue filling dam process according to claim 1, characterized in that: In step 1, the welding temperature of the eutectic welding process is 200-400° C., and the welding pressure is 0.1-5 MPa.

5. The MIP grid glue filling dam process according to claim 1, characterized in that: In step 2 and arrangement 4, the curing temperature of the molding process is 80-150° C., and the curing time is 10-120 minutes.

6. The MIP grid glue filling dam process according to claim 1, characterized in that: In step 1, the depth of the controlled cutting is 30%-70% of the thickness of the substrate (1).

7. The MIP grid glue filling dam process according to claim 1, characterized in that: In step five, the bowl body (3) is flush with the top of the dam structure (5).

8. A new type of LED lamp bead, characterized by: It is prepared by the MIP grid glue filling dam process according to any one of claims 1-7.

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