Base-free LED lamp bead with bowl cup and manufacturing method of base-free LED lamp bead

Abstract

The invention discloses a base-free LED lamp bead with a bowl cup and a manufacturing method of the base-free LED lamp bead with the bowl cup, the base-free LED lamp bead with the bowl cup comprises a bowl cup main body, an inverted LED chip and a reflecting colloid, and the bowl cup main body is provided with a through cup cavity; the flip LED chip is located in the through-type cup cavity, and the bottom of the flip LED chip is provided with a chip bonding pad. The bottom of the through-type cup cavity is filled with the reflecting colloid, the inverted LED chip is fixed, and the reflecting colloid is provided with an exposed window for exposing a chip bonding pad. The base-free LED lamp bead with the bowl cup has the advantages of being low in cost, high in brightness and good in heat dissipation performance.

Description

Technical Field

[0001] This invention relates to the field of LED lamp bead technology, and in particular to a baseless LED lamp bead with a cup-shaped base and its manufacturing method. Background Technology

[0002] Based on the current development status of LED packaging technology, the industry mainly adopts two packaging forms: base-mounted packaging and baseless CSP packaging. Base-mounted packaging is widely used due to its mature process equipment, flexible and diverse forms, and the light-concentrating and brightness-enhancing advantages brought by the cup structure. However, it relies on precious metals such as gold, silver, and copper as bases, which leads to a significant increase in packaging costs against the backdrop of continuously rising precious metal prices. Although baseless CSP packaging achieves cost reduction and heat dissipation optimization by eliminating the base and using flip chips, it has problems such as insufficient process maturity, limited form, and reduced brightness due to the lack of cups. Summary of the Invention

[0003] The technical problem solved by this invention is to provide a low-cost, high-brightness baseless LED with a cup-shaped base, and to provide a method for manufacturing the baseless LED with a cup-shaped base.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a baseless LED lamp bead with a bowl-shaped cup, comprising a bowl-shaped cup body, a flip-chip LED chip, and a reflective colloid. The bowl-shaped cup body has a through-type cup cavity; the flip-chip LED chip is located in the through-type cup cavity, and the bottom of the flip-chip LED chip has a chip pad; the reflective colloid fills the bottom of the through-type cup cavity and fixes the flip-chip LED chip, and the reflective colloid has an exposed window for exposing the chip pad.

[0005] To solve the above-mentioned technical problems, the second technical solution adopted by the present invention is: a method for manufacturing baseless LED beads with cups, used to manufacture the above-mentioned baseless LED beads with cups, comprising the following steps: Obtain the bowl / cup body, inverted LED chip, and high-temperature tape; The bottom surface of the bowl-shaped cup body and the chip pads of the flip-chip LED are successively bonded to high-temperature tape, wherein the flip-chip LED is located inside the through-hole of the bowl-shaped cup body. Apply reflective colloid to the inside of the through-type cup cavity, so that the reflective colloid fills the bottom of the through-type cup cavity; High-temperature curing of reflective colloids allows the reflective colloids to fix and connect the flip-chip LED and the bowl / cup body; Remove the high-temperature tape.

[0006] The beneficial effects of this invention are as follows: This novel baseless LED chip with a cup design uses reflective colloid to fix the flip-chip LED to the cup body, and exposes the chip pads directly through the exposed window of the reflective colloid as the chip pads. This completely eliminates the need for a metal base made of precious metals such as gold, silver, or copper, which is required in traditional packaging, significantly reducing raw material costs. At the same time, by retaining the cup structure, it maintains the light-focusing and brightness enhancement effect, overcoming the insufficient brightness defect of baseless CSP packaging. The flip-chip structure eliminates the need for wire bonding, simplifying the process and improving heat dissipation. In addition, the retention of the cup body allows this solution to make full use of existing mature base-packaged process equipment for production, balancing process maturity and form flexibility, and achieving comprehensive optimization in terms of cost, performance, and process compatibility.

[0007] This method for manufacturing baseless LED chips with a cup is simple and easy to implement. By using high-temperature tape as a temporary support, it achieves precise positioning and temporary fixation of the cup body and the flip-chip, providing a stable process foundation for the filling and curing of the reflective adhesive. The reflective adhesive filling and curing method completes the fixed connection between the flip-chip and the cup body and the exposed forming of the chip pads in one step, eliminating the need for complex metal base forming and electroplating processes. This significantly simplifies the production process and reduces equipment investment and the cost of precious metal materials. The entire manufacturing process makes full use of existing mature equipment and technologies for base-based packaging, with strong process compatibility, high production efficiency, and suitability for large-scale industrial applications. It can effectively ensure the consistency and stability of product quality. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0009] Figure 1 This is a schematic diagram of the baseless LED lamp bead with a bowl-shaped base, as shown in Embodiment 1. Figure 1 ; Figure 2 This is a schematic diagram of the baseless LED lamp bead with a bowl-shaped base, as shown in Embodiment 1. Figure 2 ; Figure 3 This is a cross-sectional view of the baseless LED lamp bead with a bowl-shaped base, as shown in Embodiment 1. Figure 4 A schematic diagram of the bowl / cup body, inverted LED chip, and high-temperature tape; Figure 5 A schematic diagram of the assembled structure of the bowl / cup body, the flip-chip LED chip, and the high-temperature tape; Figure 6 This is a cross-sectional view of a baseless LED lamp bead with a cup-shaped base after the reflective colloid has been cured. Figure 7 A cross-sectional view of a baseless LED bead with a cup-shaped base after the encapsulating adhesive has cured; Figure 8 This is a schematic diagram of the baseless LED lamp bead with a bowl-shaped base, as shown in Embodiment 2. Figure 9 A schematic diagram of the structure of the bowl / cup body after the extended solder pads are provided in Embodiment 2; Figure 10 This is a schematic diagram of the structure of the semi-finished product obtained by the method for manufacturing baseless LED beads with a bowl cup in Example 2; Figure 11 This is a schematic diagram of the baseless LED lamp bead with a bowl-shaped base, as shown in Example 3. Figure 12 This is a cross-sectional view of the baseless LED lamp bead with a bowl-shaped base in Embodiment 3; Figure 13 A schematic diagram of the structure of the bowl / cup body, inverted LED chip, metal frame, and high-temperature tape; Figure 14 This is a schematic diagram of the structure of the semi-finished product obtained by the method for manufacturing baseless LED beads with a bowl cup in Example 3.

[0010] Explanation of icon numbers: 1. Bowl / cup body; 11. Through-type cup cavity; 12. Groove; 2. Flip-chip LED; 21. Chip pads; 3. Reflective colloid; 31. Exposed window; 32. Curved surface; 4. Sealing adhesive; 5. High-temperature tape; 6. Expand the pads; 7. Metal frame. Detailed Implementation

[0011] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings.

[0012] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0013] It should be noted that if the embodiments of the present invention involve directional indicators such as up, down, left, right, front, back, etc., the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture as shown in the figure. If the specific posture changes, the directional indicators will also change accordingly.

[0014] Furthermore, if the embodiments of the present invention involve descriptions such as "first" or "second," such descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature.

[0015] Furthermore, if the meaning of "and / or" in the entire text is to include three parallel solutions, taking "and A / or B" as an example, it includes solution A, solution B, and a solution that simultaneously satisfies both A and B. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0016] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0017] Example 1 Please refer to Figures 1 to 7 Embodiment 1 of the present invention is as follows: Figures 1 to 3 As shown, the baseless LED lamp bead with a bowl-shaped cup includes a bowl-shaped cup body 1, a flip-chip LED 2, and a reflective colloid 3. The bowl-shaped cup body 1 has a through-type cup cavity 11; the flip-chip LED 2 is located in the through-type cup cavity 11, and the bottom of the flip-chip LED 2 has a chip pad 21; the reflective colloid 3 fills the bottom of the through-type cup cavity 11 and fixes the flip-chip LED 2, and the reflective colloid 3 has an exposed window 31 for the chip pad 21 to be exposed. The chip pad 21 directly serves as the conductive pad of the baseless LED lamp bead with a bowl-shaped cup.

[0018] The baseless LED chip with a cup-shaped housing also includes an encapsulating adhesive 4 filling the through-cup cavity 11. The encapsulating adhesive 4 covers the flip-chip LED 2 and the reflective adhesive 3, preferably with the top surface of the encapsulating adhesive 4 coplanar with the top surface of the cup body 1. By filling the through-cup cavity 11 with the encapsulating adhesive 4 covering the flip-chip LED 2 and the reflective adhesive 3, the flip-chip LED 2 can be effectively protected from external environmental corrosion, improving the chip's moisture-proof, dust-proof performance and long-term operational reliability.

[0019] In other embodiments, the encapsulating adhesive 4 can be a transparent colloid, while in this embodiment, the encapsulating adhesive 4 is a fluorescent colloid doped with phosphor. Using a fluorescent colloid doped with phosphor as the encapsulating adhesive 4 can realize the wavelength conversion of the light emitted by the flip-chip LED chip 2, and obtain white light of the required color temperature or light of a specific color through the excitation of phosphor, which simplifies the color light control process and improves color consistency.

[0020] Preferably, the bottom surface of the chip pad 21, the bottom surface of the reflective colloid 3, and the bottom surface of the cup body 1 are coplanar, ensuring that the bottom of the baseless LED lamp bead with cup is flat, which helps to improve the stability and accuracy of the chip mounting operation, ensures full contact between the chip pad 21 and the circuit board pad, and thus optimizes the electrical and thermal conductivity and the reliability of the chip mounting.

[0021] In one or more embodiments, the bottom surface of the bowl / cup body 1 has a groove 12 surrounding the through-cup cavity 11, and the reflective adhesive 3 fills the groove 12. By providing a groove 12 surrounding the through-cup cavity 11 on the bottom surface of the bowl / cup body 1 and filling it with reflective adhesive 3, the contact area and mechanical interlocking force between the reflective adhesive 3 and the bowl / cup body 1 are increased, significantly improving the bonding strength between the reflective adhesive 3 and the bowl / cup body 1, preventing interface peeling caused by thermal expansion and contraction or external forces, and enhancing structural stability.

[0022] The top surface of the reflective colloid 3 is an arc surface 32, which smoothly transitions with the inner peripheral wall of the through-type cup cavity 11. By setting the top surface of the reflective colloid 3 as an arc surface 32 that smoothly transitions with the inner peripheral wall of the through-type cup cavity 11, the reflection path of light can be effectively optimized, light loss and total internal reflection at the interface can be reduced, and light extraction efficiency can be improved.

[0023] The reflective colloid 3, through its high reflectivity, reflects the light emitted by the flip-chip LED 2, reducing light loss within the through-cup cavity 11 and significantly improving light extraction efficiency and intensity. In a preferred embodiment, the reflective colloid 3 is a high-temperature resistant, high-reflectivity colloid, such as silicone-based or epoxy resin-based reflective colloids. The high-temperature resistant reflective colloid 3 is less prone to yellowing and discoloration, which helps ensure the luminous quality of the baseless LED chip with a cup-shaped housing.

[0024] This embodiment also provides a method for manufacturing a baseless LED lamp bead with a cup-shaped base, which includes the following steps: S1. Obtain the bowl / cup body 1, the inverted LED chip 2, and the high-temperature tape 5, as follows: Figure 4 As shown; S2. The bottom surface of the bowl / cup body 1 and the chip pad 21 of the flip-chip LED chip 2 are successively bonded to the high-temperature adhesive tape 5. The flip-chip LED chip 2 is located within the through-hole cavity 11 of the bowl / cup body 1. Figure 5 As shown; S3. Place reflective colloid 3 inside the through-hole cup cavity 11 so that the reflective colloid 3 fills the bottom of the through-hole cup cavity 11. S4. High-temperature curing of reflective colloid 3, which fixes the reflective colloid 3 to the flip-chip LED chip 2 and the bowl / cup body 1, as shown. Figure 6 As shown; S5. Remove the high-temperature tape 5, as shown. Figure 3 As shown.

[0025] Before or after step S5, step S50 is also included: applying encapsulating adhesive 4 into the through-hole cup cavity 11 and curing the encapsulating adhesive 4, as shown below. Figure 7 As shown. Step S50 has a high degree of flexibility in process settings and can adapt to different process flow arrangements.

[0026] Step S5 is followed by step S6, which involves dividing the semi-finished product to obtain individual LED beads.

[0027] When implementing step S3, it is preferable to fill the gap between the bottom surface of the flip-chip 2 body and the high-temperature tape 5 with reflective adhesive 3 to ensure that the reflective adhesive fully wraps the bottom of the flip-chip 2. After the reflective adhesive is cured, it forms a tight fit with the chip to ensure the sealing of the baseless LED bead with cup.

[0028] The bowl / cup body 1 can be manufactured by injection molding. Its material can be either thermoplastic or thermosetting. Thermoplastic materials include, but are not limited to, PPA, PCT, and LCP, while thermosetting materials include, but are not limited to, EMC and SMC. The bowl / cup body 1, made entirely of plastic, contains no metal.

[0029] When performing step S2, a die bonder can be used to attach the flip-chip LED 2 to the area of ​​the high-temperature tape 5 corresponding to the through-hole 11, thereby completing the positioning of the flip-chip LED 2.

[0030] After implementing step S4, the reflective colloid 3 achieves bottom sealing of the through-cup cavity 11 and fixation of the LED chip position.

[0031] Example 2 Please refer to Figures 8 to 10 Embodiment 2 of the present invention is a further improvement on Embodiment 1. The difference from Embodiment 1 is that the bottom surface of the bowl-shaped body 1 is also provided with an extended solder pad 6. By adding an extended solder pad 6 to the bottom surface of the bowl-shaped body 1, the welding area of ​​the baseless bowl-shaped LED lamp bead and the circuit board is effectively increased, which significantly improves the bonding force and mechanical strength after mounting. At the same time, the extended solder pad 6 can serve as an auxiliary heat dissipation channel, further improving the heat dissipation efficiency and long-term working reliability of the baseless bowl-shaped LED lamp bead.

[0032] In this embodiment, the extended pad 6 is formed by printing or physical vapor deposition (PVD). The extended pad 6 is formed by printing or PVD, both of which are mature processes with controllable costs. Printing is suitable for large-scale mass production with low equipment investment, while PVD can obtain a dense and strongly adhesive metal film layer, meeting the differentiated performance requirements of pads in different application scenarios.

[0033] In this embodiment, the extended pads 6 are respectively provided on both sides of the through-hole cup cavity 11; in other embodiments, the extended pads 6 can also be arranged around the through-hole cup cavity 11. By arranging the extended pads 6 on both sides or around the through-hole cup cavity 11, the position and number of the extended pads 6 can be flexibly designed according to the circuit board pad layout, which is beneficial to improving the adaptability and design flexibility of baseless cup-shaped LED beads. Symmetrical or surrounding arrangement is beneficial to balanced heat dissipation and stress distribution, which is beneficial to further improve the reliability of surface mount technology.

[0034] When manufacturing the baseless LED lamp bead with a bowl in this embodiment, before implementing step S2, step S20 is also included: setting an extended pad 6 on the bottom surface of the bowl body 1.

[0035] Implementation step S20 specifically includes: forming an extended pad 6 on the bottom surface of the bowl-shaped body 1 using a physical vapor deposition (PVD) process. The raw materials used in the PVD process include, but are not limited to, metals such as gold, silver, copper, and tin. Forming the extended pad 6 using PVD yields a metal film layer with high purity, good density, and strong adhesion. The film thickness is precisely controllable, and the process is environmentally friendly with excellent film uniformity.

[0036] Alternatively, step S20 may specifically include: first, forming a conductive ink layer on the bottom surface of the bowl / cup body 1 using inkjet printing or screen printing; then, plating silver or tin onto the conductive ink layer using chemical plating or electroplating to form extended solder pads 6. Using inkjet printing or screen printing combined with chemical plating or electroplating to form the extended solder pads 6 fully leverages the advantages of low cost, high efficiency, and flexible pattern design in printing processes. Combined with subsequent silver or tin plating, excellent soldering performance can be achieved, making it suitable for large-scale, low-cost production. The conductive ink layer may be nano-silver ink, nano-copper ink, or graphene ink, etc. When the conductive ink layer is nano-copper ink or graphene ink, it needs to be plated with silver or tin.

[0037] When implementing step S6, the integral bowl and cup body 1 in the semi-finished product is cut to obtain a single LED bead.

[0038] Example 3 Please refer to Figures 11 to 14 The third embodiment of the present invention is a further improvement on the first embodiment. The difference from the first embodiment is that the bottom surface of the bowl-shaped body 1 is also provided with an extended solder pad 6. By adding an extended solder pad 6 to the bottom surface of the bowl-shaped body 1, the welding area of ​​the baseless bowl-shaped LED lamp bead and the circuit board is effectively increased, which significantly improves the bonding force and mechanical strength after mounting. At the same time, the extended solder pad 6 can serve as an auxiliary heat dissipation channel, further improving the heat dissipation efficiency and long-term working reliability of the baseless bowl-shaped LED lamp bead.

[0039] In this embodiment, a metal frame 7 is embedded within the bowl-shaped body 1, and the bottom surface of the metal frame 7 is exposed above the bottom surface of the bowl-shaped body 1 to form the extended pad 6. By embedding the metal frame 7 within the bowl-shaped body 1 and exposing its bottom surface to form the extended pad 6, the high thermal conductivity of the metal frame 7 enhances the heat dissipation capacity of the baseless bowl-shaped LED beads. At the same time, the embedded structure avoids additional thickness increase of the baseless bowl-shaped LED beads, achieving a dual optimization of structural compactness and heat dissipation performance.

[0040] The metal frame 7 can be formed by stamping or etching. Since the metal frame 7 is only used to strengthen the bonding force of the patch, very inexpensive metal materials such as iron and stainless steel can be used (compared to copper). Moreover, since there is no need to consider heat dissipation, the thickness of the metal frame 7 can be very thin, even less than or equal to 0.2mm, which helps to further reduce costs.

[0041] In this embodiment, the extended pads 6 are respectively provided on both sides of the through-hole cup cavity 11; in other embodiments, the extended pads 6 can also be arranged around the through-hole cup cavity 11. By arranging the extended pads 6 on both sides or around the through-hole cup cavity 11, the position and number of the extended pads 6 can be flexibly designed according to the circuit board pad layout, which is beneficial to improving the adaptability and design flexibility of baseless cup-shaped LED beads. Symmetrical or surrounding arrangement is beneficial to balanced heat dissipation and stress distribution, which is beneficial to further improve the reliability of surface mount technology.

[0042] When manufacturing the baseless LED lamp bead with a bowl in this embodiment, before implementing step S2, the step further includes: setting an extended pad 6 on the bottom surface of the bowl body 1.

[0043] In the implementation step S1 of this embodiment, obtaining the bowl / cup body 1 specifically includes: obtaining a metal frame 7 and injection molding the bowl / cup body 1 based on the metal frame 7, wherein the bottom surface of the metal frame 7 is exposed on the bottom surface of the bowl / cup body 1 to form an extended solder pad 6. By embedding the metal frame 7 into the injection-molded bowl / cup body 1 and exposing the bottom surface to form the extended solder pad 6, the integrated molding of the bowl / cup body 1 and the extended solder pad 6 is achieved, simplifying the processing steps of the extended solder pad 6. The metal frame 7 has a strong bonding force with the plastic bowl / cup, resulting in high production efficiency and suitability for automated mass production.

[0044] Preferably, after obtaining the metal frame 7 and before injection molding the bowl / cup body 1 based on the metal frame 7, the method further includes an electroplating step for the metal frame 7 to improve its weldability. Since the metal frame 7 does not need to consider conductivity and light reflectivity, it can be directly tin-plated or plated with a very thin silver layer to reduce costs.

[0045] When performing step S6, the metal frame 7 in the semi-finished product is cut to obtain a single LED bead.

[0046] The above are merely optional embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A baseless LED lamp bead with a bowl-shaped base, characterized in that: include The main body of the bowl / cup has a continuous cavity. The flip-chip LED is located inside the through-hole cup cavity, and has chip pads at the bottom; A reflective colloid fills the bottom of a through-cup cavity and secures the flip-chip LED, which has an exposed window for exposing the chip pads.

2. The baseless LED lamp bead with a bowl-shaped base according to claim 1, characterized in that, The bottom surface of the bowl / cup body has a groove surrounding the through-type cup cavity, and the reflective colloid fills the groove.

3. The baseless LED lamp bead with a bowl-shaped base according to claim 1, characterized in that, The bottom surface of the bowl / cup body is also provided with an extended pad, which is formed by printing or physical vapor deposition; or, the bowl / cup body is embedded with a metal frame, the bottom surface of which is exposed on the bottom surface of the bowl / cup body to form the extended pad.

4. A method for manufacturing baseless LED beads with a bowl-shaped base, characterized in that, The method for manufacturing the baseless LED lamp bead with a bowl-shaped design as described in claim 1 comprises the following steps: Obtain the bowl / cup body, inverted LED chip, and high-temperature tape; The bottom surface of the bowl-shaped cup body and the chip pads of the flip-chip LED are successively bonded to high-temperature tape, wherein the flip-chip LED is located inside the through-hole of the bowl-shaped cup body. Apply reflective colloid to the inside of the through-type cup cavity, so that the reflective colloid fills the bottom of the through-type cup cavity; High-temperature curing of reflective colloids allows the reflective colloids to fix and connect the flip-chip LED and the bowl / cup body; Remove the high-temperature tape.

5. The method for manufacturing baseless LED beads with a bowl-shaped base according to claim 4, characterized in that, Before or after removing the high-temperature tape, the procedure also includes applying encapsulating adhesive inside the through-cup cavity and curing the encapsulating adhesive.

6. The method for manufacturing baseless LED beads with a bowl-shaped base according to claim 4, characterized in that, Before bonding the bottom surface of the bowl / cup body to the high-temperature tape, the process also includes the step of setting extended solder pads on the bottom surface of the bowl / cup body.

7. The method for manufacturing baseless LED beads with a bowl-shaped base according to claim 6, characterized in that, Setting extended pads on the bottom surface of the bowl / cup body specifically includes: forming extended pads on the bottom surface of the bowl / cup body using a physical vapor deposition process.

8. The method for manufacturing baseless LED beads with a bowl-shaped base according to claim 6, characterized in that, Setting extended pads on the bottom surface of the bowl / cup body specifically involves: first, forming a conductive ink layer on the bottom surface of the bowl / cup body using inkjet printing or screen printing; then, plating silver or tin onto the conductive ink layer using chemical plating or electroplating to form extended pads.

9. The method for manufacturing a baseless LED lamp bead with a bowl-shaped base according to claim 6, characterized in that, The specific steps of obtaining the bowl / cup body include: obtaining a metal frame and injection molding the bowl / cup body based on the metal frame, wherein the bottom surface of the metal frame is exposed on the bottom surface of the bowl / cup body to form an extended solder pad.

10. The method for manufacturing baseless LED beads with a bowl-shaped base according to claim 4, characterized in that, When applying reflective colloid inside the through-hole cup cavity, the reflective colloid fills the gap between the bottom surface of the flip-chip body and the high-temperature tape.

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