LED light emitting device

Abstract

The present invention is applicable to the field of LED packaging and provides an LED light-emitting device and a manufacturing method thereof. The LED light-emitting device includes a mount, an LED chip, and a packaging adhesive layer. The mount has a substrate and a dam portion. The substrate has opposite front and back surfaces, and the dam portion has opposite bottom and top surfaces. The LED chip and the bottom surface of the dam portion are located on the front surface of the substrate. The dam portion surrounds the LED chip and forms a chip mounting area used for mounting the LED chip and placing a packaging adhesive layer. The packaging adhesive layer is packaged above the LED chip. The dam portion and the packaging adhesive layer are transparent or translucent, and the top of the packaging adhesive layer is provided with transparent or translucent hollow particles. The LED light-emitting device and manufacturing method thereof of the present invention result in a product with high brightness and a good user experience.

Description

[Technical Field]

[0001] The present invention belongs to the technical field of LED packaging, and more particularly to an LED light emitting device and a manufacturing method thereof. [Background technology]

[0002] In recent years, the rapid development of LCD technology has led to larger screen sizes. Driven by the demand for high dynamic range (HDR) and the "home economy," Mini LED display technology has gradually been adopted for medium- to large-sized applications such as televisions, commercial displays, and e-sports. Currently, the mainstream Mini backlight technology is blue-light LEDs with quantum dot film, which employs surface dots or white adhesive spray technology (e.g., CN112186090A) on the lamp bead. While this achieves a 160° light-emitting angle, the light intensity at the center of the LED lamp bead is significantly sacrificed because the light-shielding layer (white adhesive) blocks a large amount of light, significantly reducing the luminous flux of the lamp bead. This results in low product brightness and a poor user experience.

[0003] In the prior art, some methods use transparent mounts. For example, the display device and its four-way light-emitting LED disclosed in CN107086263B use a four-way light-emitting form. The transparent mount is molded onto the substrate by heat molding, and generally uses transparent plastics such as PPA (polyphthalamide), PCT (polyethylene terephthalate), and thermoplastic resin. The light transmittance is insufficient, affecting the light intensity on the sides. In addition, a reflective white adhesive layer is provided on the top, which causes a large loss of light intensity on the top, resulting in a poor actual experience. Summary of the Invention [Problem to be solved by the invention]

[0004] The purpose of the present invention is to overcome the drawbacks of the prior art and provide an LED light emitting device and a manufacturing method thereof that can reduce the light intensity loss at the top of the LED light emitting device, which is beneficial for improving the brightness of the LED light emitting device and providing a good practical experience. [Means for solving the problem]

[0005] The technical solution of the present invention is as follows: An LED light emitting device comprising: a mount, an LED chip, and a packaging adhesive layer, the mount having a substrate and a dam portion, the substrate having opposing front and back surfaces, the dam portion having opposing bottom and top surfaces, the LED chip and the bottom surface of the dam portion being located on the front surface of the substrate, the dam portion surrounding the LED chip and forming a chip mounting area used for mounting the LED chip and placing the packaging adhesive layer, the packaging adhesive layer being packaged above the LED chip, the dam portion and the packaging adhesive layer being transparent or translucent, a top surface of the packaging adhesive layer being provided with transparent or translucent hollow particles, the height of the dam portion being the distance from the front surface of the substrate to the top surface of the dam portion, the height by which the packaging adhesive layer protrudes from the mount being the distance from the top surface of the dam portion to the tip of the packaging adhesive layer, and the height by which the packaging adhesive layer protrudes from the mount being greater than the height of the dam portion.

[0006] Optionally, the outer surface of the packaging adhesive layer is curved, larger at the bottom and smaller at the top, the top of the packaging adhesive layer is located directly above the chip mounting area, and the hollow particles cover directly above the LED light-emitting device.

[0007] Optionally, at least a portion of the packaging adhesive layer is not covered by the hollow particles, and the hollow particles cover at least directly above the LED chip.

[0008] Optionally, the projected area of ​​the region covered by the hollow particles on the bottom surface of the packaging adhesive layer accounts for 20 to 80% of the bottom surface area of ​​the packaging adhesive layer, or the thickness of the portion of the surface of the packaging adhesive layer that is not covered by the hollow particles is at least greater than the height of the dam portion.

[0009] Optionally, the packaging adhesive layer comprises a first packaging adhesive layer and a second packaging adhesive layer, the bottom of the first packaging adhesive layer being packaged on the front side of the substrate, the bottom of the second packaging adhesive layer being packaged on the top of the first packaging adhesive layer, a phosphor being provided in the first packaging adhesive layer, most of the phosphor being located at the bottom of the first packaging adhesive layer, and a top surface of the first packaging adhesive layer being lower than a top surface of the dam portion.

[0010] Optionally, the mass content of the hollow particles in the second packaging adhesive layer is 1 to 5%.

[0011] Optionally, the hollow particles have a median diameter of 15 μm to 100 μm.

[0012] Optionally, a top surface of said dam portion is inclined inwardly of said dam portion.

[0013] The present invention is a method for manufacturing an LED light emitting device, Used to manufacture the above LED light-emitting device, manufacturing the mount and applying the packaging adhesive layer having the hollow particles to the mount; and making the height of the packaging adhesive layer protruding from the mount greater than the height of the mount.

[0014] Optionally, the step of providing a packaging adhesive layer comprises: providing a first package adhesive containing a phosphor in the dam portion, then sedimenting the phosphor through a centrifugal process, and curing or semi-curing the first package adhesive through a high-speed baking process; and applying a second packaging adhesive containing the hollow particles above the first packaging adhesive, and baking the second packaging adhesive to cause the hollow particles to aggregate on top of the second packaging adhesive, thereby forming a hollow particle aggregation region.

[0015] In the LED light-emitting device and manufacturing method thereof according to the present invention, the hollow particles, with their low density and light weight, can gather in the area above the packaging adhesive when heated. They are white particles with reflective and refractive properties, allowing light directly above the lamp bead to undergo secondary mixing due to the reflection and refraction of the hollow particles. This causes the light intensity in the center of the lamp bead to be strongly refracted and reflected to both sides, improving the light intensity on both sides of the lamp bead. Furthermore, the hollow structure of the hollow particles improves light transmission, increasing the light emission angle without significantly reducing the overall brightness of the lamp bead. Furthermore, because the hollow particles are suspended above the LED chip and are separated from the fluorescent adhesive (the adhesive in the second packaging adhesive layer separates the fluorescent adhesive and the hollow particles), most of the light can be emitted from the adhesive between the hollow particles and the fluorescent adhesive, relatively enhancing the light intensity on both sides. When applied to display backlight lamp panels, it can increase the pitch of lamp beads on the lamp panel, reduce the number of lamp beads on the same lamp panel, and reduce the cost of lamp beads, improving the brightness of display products, improving the user experience, and reducing application costs. [Brief explanation of the drawings]

[0016] In order to more clearly explain the technical solutions in the embodiments of the present invention, the drawings that need to be used in the embodiments will be briefly described below. However, the drawings in the following description are only some embodiments of the present invention, and it is obvious that those skilled in the art can obtain other drawings based on these drawings without any creative efforts. [Figure 1] 2 is a cross-sectional view of a mount for an LED light emitting device according to an embodiment of the present invention; [Figure 2a] 3 is a cross-sectional view of the mount and the first package adhesive layer of the LED light emitting device according to the embodiment of the present invention. [Figure 2b] 10 is a cross-sectional view of the mount and the first packaging adhesive layer of an LED light emitting device according to another embodiment of the present invention. [Figure 3a] FIG. 5B is a cross-sectional view of FIG. 5A or FIG. 5B. [Figure 3b] FIG. 5B is a cross-sectional view of FIG. 5A or FIG. 5B. [Figure 3c] FIG. 5B is a cross-sectional view of FIG. 5A or FIG. 5B. [Figure 4] 3 is a schematic diagram showing the ratio of hollow particles to the bottom area of ​​the packaging adhesive layer in a plan view of an LED light emitting device according to an embodiment of the present invention; [Figure 5a] 2 is a schematic diagram of the top view of the LED light emitting device according to the embodiment of the present invention; [Figure 5b] 3 is a schematic diagram of the top view of another LED light emitting device according to an embodiment of the present invention; [Figure 6a] 3a is a schematic illustration of the optical effect of FIG. 3a. [Figure 6b] FIG. 3b is a schematic illustration of the optical effect of FIG. [Figure 7] 1 is a schematic diagram of a light effect in the prior art; [Figure 8] 6b is a schematic diagram of the light intensity distribution of the LED light emitting device shown in FIG. [Figure 9] 1 is a schematic diagram of the light intensity distribution of a conventional LED light-emitting device whose top surface is covered with a white adhesive. [Figure 10]10 is a schematic cross-sectional view of an LED light-emitting device according to another embodiment. FIG. [Figure 11] 2 is a schematic diagram of the top view of the LED light emitting device according to the embodiment of the present invention when applied to a backlight lamp panel; [Figure 12] 3 is a schematic diagram of the optical effect when the LED light emitting device according to the embodiment of the present invention is applied to a backlight lamp panel. [Figure 13] 10 is a schematic diagram of the cross-sectional structure and optical effect of an LED light-emitting device according to another embodiment. [Figure 14] 10 is a schematic diagram of the cross-sectional structure and optical effect of an LED light-emitting device according to another embodiment. [Figure 15] 10 is a schematic cross-sectional view of an LED light-emitting device according to another embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0017] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be described in more detail below with reference to the drawings and examples. It should be understood that the specific examples described herein are for the purpose of illustrating the present invention, but are not intended to limit the present invention.

[0018] It should be noted that when an element is said to be "fixed" or "mounted" to another element, it may be directly disposed on the other element or a central element may also be present. When an element is said to be "connected" to another element, it may be directly connected to the other element or a central element may also be present.

[0019] Furthermore, in the embodiments of the present invention, terms indicating orientation or positional relationship, such as "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," are based on the orientation or positional relationship shown in the drawings or on conventional arrangements or usage states, and are used merely to facilitate and simplify the description of the present invention. They do not indicate or imply that such structures, features, devices, or elements must have a particular orientation or positional relationship, or be configured and operated in a particular orientation, and therefore cannot be construed as limiting the present invention. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0020] Each specific technical feature and each example described in a specific embodiment may be combined in any appropriate manner unless there is a contradiction. For example, various specific technical features / examples may be combined to form various embodiments. In order to avoid unnecessary duplication, various combinations of each specific technical feature / example in the present invention will not be described separately.

[0021] As shown in Figures 1, 2a, 2b, 3a, 3b, and 3c, an LED light emitting device (lamp bead) 10 according to an embodiment of the present invention includes a mount 120, an LED chip 200, and a packaging adhesive layer 400. The mount 120 includes a substrate 100 and a dam portion 110 . The substrate 100 may be a metal substrate, a ceramic substrate with a metal plating layer, a glass substrate, or another conductive substrate. The substrate 100 has opposing front and back surfaces, and a dam portion 110 has opposing bottom and top surfaces. The LED chip 200 and the dam portion 110 are provided on the front surface of the substrate 100. The dam portion 110 surrounds the LED chip 200 and forms a chip mounting area 130 for mounting the LED chip and applying a packaging adhesive. The shape of the chip mounting area 130 can vary depending on the application and lighting effect requirements. For example, the chip mounting area 130 in the example of FIG. 5a is rectangular, and the chip mounting area 130 in the example of FIG. 5b is circular. However, the chip mounting area 130 may have other shapes; the present application does not limit the shape of the chip mounting area 130. The packaging adhesive layer 400 is packaged above the LED chip 200. The dam portion 110 and the packaging adhesive layer 400 are transparent or translucent, allowing light to exit from the entire side of the LED light-emitting device (including the dam portion 110), improving the lighting effect from the side. The packaging adhesive layer 400 may be made of a highly light-transmitting resin such as epoxy resin or silicone resin. The dam portion 110 may be made of a transparent material, including but not limited to EKE091, PPA, and PCT. Transparent or translucent hollow particles are provided on the top of the packaging adhesive layer 400. In this embodiment, the hollow particles are glass microspheres with a hollow center. These particles have chemical properties similar to soda-lime borosilicate glass compositions, are water-resistant, non-flammable, and non-porous, and therefore do not absorb resin (packaging adhesive), are compatible with resin, and are low in application cost. Furthermore, the hollow particles have low density and light weight, so that they can be gathered in the upper region of the packaging adhesive layer 200 when heated, and can be suspended above the LED chip 200. The hollow particles are transparent particles with reflective and refractive properties, so that light directly above the lamp bead is reflected and refracted by the hollow particles (hollow particles have a transparent or translucent hollow structure and a small particle diameter, which allows them to refract and reflect light, making them appear white), thereby improving the light intensity in the regions on both sides of the lamp bead.

[0022] The height H1 of the dam 120 is the distance from the front surface of the substrate 100 to the top surface of the dam portion 110. The height H2 of the package adhesive layer 400 protruding from the mount 120 is the distance from the top surface of the dam portion 110 to the tip of the package adhesive layer 400. The height H2 of the package adhesive layer 400 protruding from the mount 120 is greater than the height of the mount 120, i.e., H2 is greater than H1 (preferably, H2 is 1 to 2 times H1). This improves the proportion of the height of the package adhesive layer 400 protruding from the mount 120 to the total height of the LED light-emitting device, and concentrates the hollow particles near the top of the package adhesive layer 400 above the LED chip 200, allowing the hollow particles to reflect the light emitted from the top surface of the LED chip 200. Meanwhile, the package adhesive layer 400 protruding from the mount 120 helps to arrange the hollow particles in a higher area (see FIGS. 6A, 6B, and 14). This reduces the blocking of light reflected and refracted by the hollow particles, facilitating reflection and refraction of light toward the sides of the LED light-emitting device, thereby reducing the blocking of light emitted from the LED chip due to the mount. Combined with the hollow particles provided on the top of the packaging adhesive layer 400, this appropriately reduces the amount of light emitted from the top of the LED light-emitting device and increases the amount of light emitted from the sides. Furthermore, as shown in FIG. 6b, because the dam portion 110 is optically transparent, light emitted from the LED chip passes through the dam portion 110 and reaches the periphery of the LED light-emitting device 10, where it overlaps with light reflected and refracted by the hollow particles. This intensifies the light around the periphery of the LED light-emitting device 10, improving the uniformity of the emitted light. As shown in Figures 11 and 12, the LED light emitting device 10 can be arranged in an array on a PCB substrate to form a backlight lamp panel for a display, which can improve the uniformity of the light intensity of the backlight lamp panel, increase the pitch of the lamp beads in the lamp panel, reduce the number of lamp beads in the same lamp panel, reduce the cost of the lamp beads, improve the brightness of the display product, and improve the experience.

[0023] Specifically, the outer surface of the packaging adhesive layer 400 is curved, larger at the bottom and smaller at the top. The top of the packaging adhesive layer 400 is located directly above the chip mounting area 130, and the hollow particles cover the LED chip 200 directly above, forming a hollow particle covering area 410 on the top of the packaging adhesive layer 400. In some embodiments, the packaging adhesive layer 400 may have a spherical crown shape, and the LED chip 200 is located at or near the center of the bottom of the packaging adhesive layer, which improves the uniformity and effectiveness of the LED light emission device.

[0024] 1, 3a, 3b, and 3c, the package adhesive layer 400 covers at least the inner surface and top of the dam portion 110 and fills at least the chip mounting area 130, thereby minimizing the blocking of light emitted from the surface of the package adhesive layer 400 by the dam portion 110 and improving the light intensity around the LED light emitting device. The package adhesive layer 400 can be formed by a dispensing process during production. If the height of the convex portion of the package adhesive layer 400 is too high, the package adhesive layer 400 may spill out of the dam portion 110 due to gravity. Therefore, in a preferred embodiment, the height H2 of the package adhesive layer 400 is less than the length H4 and / or width H5 of the dam portion 110 (see FIGS. 5a and 5b), thereby reducing spillage of the package adhesive layer 400 during production.

[0025] 5a and 5b (the hatched area in the figure is the area occupied by the dam portion 110), the dam portion 110 may be fixed to or integral with the front surface of the substrate 100. The shapes of the dam portion 110 and the chip mounting area 130 may be flexibly set, and are not limited thereto in the present application. For example, as shown in the top view of an LED light emitting device in FIG. 5a, the dam portion 110 has a rectangular outer contour and the chip mounting area 130 also has a rectangular outer contour. As shown in the top view of another LED light emitting device in FIG. 5b, the dam portion 110 has a rectangular outer contour and the chip mounting area 130 has a circular outer contour. In another embodiment, one LED chip 200 is provided in the chip mounting area 130, and the LED chip 200 is located in the center of the chip mounting area 130. However, in another embodiment, two or more LED chips 200 may be provided. In addition to the LED chip, a protection element such as a Zener diode may be mounted in the chip mounting area 130.

[0026] In specific applications, the packaging adhesive layer 400 may have a single-layer structure depending on the production process, for example, the packaging adhesive layer 400 shown in Figure 3c has a single-layer structure, and the hollow particles may be located on top of the single-layer packaging adhesive. The packaging adhesive layer 400 may also have a two-layer structure (the hollow particles may be located on top of the top packaging adhesive layer), for example, the packaging adhesive layer 400 shown in Figure 3b has a first packaging adhesive layer 300 at the bottom and a second packaging adhesive layer 420 at the top, and the hollow particles may be located on top of the second packaging adhesive layer 420. The packaging adhesive layer 400 may have a structure of three or more layers, for example, the packaging adhesive layer 400 shown in Figure 3a has a first packaging adhesive layer 300 at the bottom, a second packaging adhesive layer 420 at the middle, and a third packaging adhesive layer 430 at the top, and the hollow particles may be located on the top of the third packaging adhesive layer 430. The number of layers of the packaging adhesive layer 400 is not limited in this application.

[0027] In one embodiment, as shown in Figure 14, the hollow particle covering region 410 may completely cover the packaging adhesive layer 400 (because there are gaps between the hollow particles, completely covering here means visually substantially covering, with no obvious blank areas). In another embodiment, as shown in Figures 6a and 6b, the hollow particles may not completely cover the packaging adhesive layer 400, i.e., at least a portion of the packaging adhesive layer 400 may not be covered by the hollow particles. This may be selected depending on the light effect required for the product design and is not limited by the present application.

[0028] 3a, 3b, 3c, 4, and 6b, in one embodiment, the projected area of ​​hollow particle covering region 410 on the bottom surface of packaging adhesive layer 400 accounts for 20-80%, preferably 24-40%, of the bottom surface area of ​​packaging adhesive layer 400, thereby appropriately shifting the central light intensity of the lamp bead to both sides and improving the light intensity on both sides of the lamp bead. Also, because hollow particle covering region 410 does not cover the entire top surface of packaging adhesive layer 400, the blocking of lateral light from the LED is reduced, and the lateral light of the LED is enhanced (see FIG. 8 for the light intensity distribution).

[0029] In another embodiment, the thickness H3 of the surface of the package adhesive layer 400 that is not covered by the hollow particles is at least greater than the height of the dam portion H1, so that the light directly refracted from the package adhesive layer 400 is sufficient to overlap with the light reflected and refracted by the hollow particles, thereby enhancing the side light of the LED (see FIG. 8 for the light intensity distribution).

[0030] 3b and 6b, the package adhesive layer 400 includes a first package adhesive layer 300 and a second package adhesive layer 420, the bottom of the first package adhesive layer 300 is packaged on the front side of the substrate 100, and the bottom of the second package adhesive layer 420 is packaged on top of the first package adhesive layer 300. The first package adhesive layer 300 contains a phosphor, which can convert the wavelength of light emitted from the LED chip to generate white light or other desired light. Most of the phosphor is located at the bottom of the first package adhesive layer 300, i.e., the first package adhesive layer 300 containing the phosphor is provided in the dam portion 110, and the first package adhesive layer 300 may be a fluorescent adhesive (containing the phosphor).

[0031] As shown in FIGS. 2A and 2B, the first package adhesive layer 300 may not protrude from the dam portion 110, and most or all of the phosphor may be deposited on the upper surface of the substrate 100 and / or the LED chip 200 to form a phosphor deposited layer 320. Because the phosphor generates heat when excited, the phosphor deposited layer 320 deposited on or near the substrate facilitates heat dissipation through the substrate. The first package adhesive layer 300 has a relatively transparent transparent layer 310 at its upper end and a phosphor deposited layer 320 at its lower end. This increases the phosphor concentration near the LED chip, allowing light emitted from the LED chip to more effectively excite the phosphor. This improves excitation efficiency and reduces the phosphor blocking light passing through the transparent layer 310.

[0032] In specific applications, as shown in FIGS. 2a and 2b, the fluorescent adhesive (first package adhesive layer 300) may be lower than the top surface of the dam portion 110 and have a concave cup shape with a concave central surface and a protruding concave edge (as shown in FIG. 2b), or a half-bowl shape with a flat surface lower than the top surface of the dam portion 110 (as shown in FIG. 2a). The purpose of this is to ensure space for the convex cup-shaped adhesive (i.e., second package adhesive layer 420) formed on top in a subsequent process. This allows the adhesive to automatically flow into the empty space even if a slight deviation occurs during dispensing of the second package adhesive layer 420, preventing the second package adhesive layer 420 from spilling outside the dam portion 110, thereby reducing the difficulty of the production process and improving production yield. Furthermore, the contact area between the second package adhesive layer 420 and the first package adhesive layer 300 and the dam portion 110 can be increased, thereby enhancing the bonding strength between different layers. To precipitate at least some or all of the phosphor, a semi-solid first packaging adhesive layer 300 may be applied to a substrate, followed by a centrifuge to precipitate the phosphor, forming a phosphor precipitated layer 320, with a transparent layer applied on top of the phosphor precipitated layer 320. After the centrifugation process is complete, the phosphor adhesive (first packaging adhesive layer 300) is baked using a high-speed baking process. The high-speed baking process involves baking at a low temperature of 43°C for 30-40 minutes, followed by baking at 130-150°C for 5-10 minutes, which eliminates air bubbles in the adhesive and slightly dries the adhesive surface.

[0033] In a specific application, as shown in FIGS. 3b and 6b, the second package adhesive layer 420 has a spherical shape with its center arching upward relative to the periphery. The second package adhesive layer 420 can be formed by a dispensing process. The hollow particle collection region 410 is located in the crown portion of the spherical shape. When viewed from the cross-sectional view of FIG. 3b, the hollow particle collection region 410 has a crescent shape (thin at the edges, thick at the center, and a circular arc at the bottom) and a flat structure relative to the top (see FIG. 3a). In this embodiment, the hollow particles are only located in the crown portion (center portion) and do not need to be laid on the flat surface of the planar structure. This allows for a relatively small amount of hollow particles to be used. Furthermore, in some applications where the light intensity of the LED top surface needs to be guaranteed, this can reduce the blocking of light from the center of the LED and reduce the loss of light intensity at the top of the LED light-emitting device. Furthermore, by heating the second package adhesive layer 420, the hollow particles can be gathered upward at the protruding upper end of the second package adhesive layer 420, i.e., a hollow particle gathering region 410 can be formed in the central top region located directly above the LED chip 200, thereby facilitating production and manufacturing.

[0034] 1, the width A of the top of the dam portion 110 is 200 μm or less, and the height H1 of the dam portion 110 is 450 μm or less. By limiting the height of the dam portion 110, the light mixing area and distance above the substrate 100 can be improved, the light emission angle and the light intensity on both sides can be increased, and the blocking of light rays by the dam portion 110 can be reduced.

[0035] 2a and 2b, the inner peripheral side of the dam portion 110 is a vertical surface (see FIG. 2a) or an inwardly inclined surface (see FIG. 2b), and the outer peripheral side of the dam portion 110 is a vertical surface (see FIG. 2a) or an outwardly inclined surface (see FIG. 2b). In the embodiment shown in FIG. 2b, the inclination angle of the inner wall of the dam portion 110 relative to the front surface of the substrate 100 increases the contact area between the dam portion and the packaging adhesive layer, improving the bonding strength between the inner surface of the dam portion 110 and the adhesive of the packaging adhesive layer. This reduces the occurrence of adhesive overflow when a larger amount of packaging adhesive is used, and the greater the amount of packaging adhesive, the better the light-shaping effect.

[0036] 2b and 10, the top surface of dam portion 110 may be a flat surface 112 (see FIG. 2b) parallel to the plane of the substrate, or may be an inwardly slanted surface 114 (see FIG. 10) that is not parallel to the substrate. In the embodiment shown in FIG. 10, by slanting the top surface of dam portion 110 inward, the contact area between the dam portion and the packaging adhesive layer is increased, the bonding strength between the top surface of dam portion 110 and the adhesive in the packaging adhesive layer is improved, and the occurrence of adhesive overflow can be reduced when a larger amount of packaging adhesive is used.

[0037] In another embodiment, as shown in FIG. 13, the cross section of the dam portion 110 is triangular, i.e., the top surface of the dam portion 110 is pointed, so that the thickness of the top of the dam portion 110 can be reduced to increase the light transmittance, increase the amount of light emitted from both sides, and reduce the material of the dam portion 110. In addition, the slope area of ​​the inner surface 301 of the dam portion 110 can be increased, so that part of the light incident on the inner surface 301 can be reflected toward the periphery of the LED light-emitting device, increasing the contact area between the package adhesive layer 400 and the dam portion 110, and improving the bonding strength and airtightness between the package adhesive layer 400 and the mount 120.

[0038] Specifically, the first package adhesive (first package adhesive layer) 300 and the second package adhesive (second package adhesive layer) 420 use the same adhesive material, i.e., the second package adhesive layer 420 is made from the same manufacturer and type of adhesive as the first package adhesive layer 300 (fluorescent adhesive), thereby achieving a good bonding effect. In this embodiment, the first package adhesive layer may be silica gel, and the second package adhesive layer may also be silica gel.

[0039] Specifically, since this is effective, the content (by mass) of hollow particles in the second package adhesive layer 420 may be 1 to 5%.

[0040] Specifically, the median diameter of the hollow particles may be 15 μm to 100 μm. The median diameter is the D50 particle diameter, also known as the median diameter, and refers to the particle diameter value corresponding to a cumulative distribution rate of 50%. This is a typical value that represents particle size, and this value divides the whole into two equal parts, i.e., 50% of the particles have a particle diameter greater than this value and 50% have a particle diameter less than this value. If the D50 of a sample is 5 μm, this means that of the total particles constituting this sample, 50% have a particle diameter greater than 5 μm and 50% have a particle diameter less than 5 μm. In this example, the median diameter of the hollow particles may be 40 μm, i.e., 50% of the hollow particles have a particle diameter greater than 40 μm and 50% have a particle diameter less than 40 μm.

[0041] Specifically, taking the model 2835 LED lamp bead as an example, the height of the entire LED light emitting device may be 1.3 mm to 1.7 mm, the thickness of the hollow particles in the hollow particle gathering region 410 may be 50 to 150 μm, the outer shape of the hollow particle gathering region 410 may be approximately circular or elliptical, and the outer diameter D thereof may be 1800 to 2200 μm.

[0042] As shown in FIG. 15, in one embodiment, multiple LED light emitting devices 10 may share one substrate 500, and multiple dam portions 110 may be formed on the substrate 500 to form an LED lamp panel or string, and the substrate 500 may be a PCB substrate.

[0043] The present invention is a method for manufacturing an LED light emitting device, which is used to manufacture the above LED light emitting device, manufacturing a mount with transparent sides and applying a transparent or translucent hollow particle packaging adhesive layer to the mount; and making the height of the packaging adhesive layer protruding from the mount 120 greater than the height of the mount 120.

[0044] Hollow particles are white (transparent) particles with reflective and refractive properties. Light directly above the lamp bead is reflected and refracted by the hollow particles before reaching the outside of the lamp bead, where it undergoes secondary mixing with the outside light, reducing the light intensity in the center of the lamp bead and improving the light intensity on both sides of the lamp bead. Furthermore, the hollow structure of hollow particles has good light transmittance, improving the light intensity on the sides without significantly reducing the overall brightness of the lamp bead. Therefore, when lamp beads are applied to display backlight lamp panels, the light intensity in the areas between the lamp beads can be improved, the pitch of the lamp beads on the lamp panel can be increased, the number of lamp beads on the same lamp panel can be reduced, and the cost of lamp beads can be reduced. This improves the brightness and uniformity of display products, improving the user experience, and reducing application costs. The height of the dam portion 110 is the distance from the front surface of the substrate 100 to the top surface of the dam portion 110, and the height of the packaging adhesive layer 400 protruding from the mount 120 is the distance from the top surface of the dam portion 110 to the tip of the packaging adhesive layer, and the height of the packaging adhesive layer 400 protruding from the mount 120 is greater than the height of the dam portion 110, thereby reducing the proportion of the height of the dam portion 110 in the total height of the LED light-emitting device. By combining hollow particles on the top of the packaging adhesive layer, the amount of light emitted from the top and sides of the LED light-emitting device can be increased and the uniformity of the emitted light can be improved compared to conventional technologies, thereby improving the user experience of the LED light-emitting device.

[0045] Specifically, in one embodiment, the step of manufacturing the mount includes the steps of manufacturing a substrate 100, and integrally molding or fixing a closed-shaped dam portion 110 on the substrate 100 to form a chip mounting area 130; The method may further include the step of connecting the LED chip 200 to the substrate 100 and disposing the LED chip 200 inside the dam portion 110 (ie, within the chip mounting region 130).

[0046] In one embodiment, the step of providing the package adhesive layer may include the steps of providing a semi-solid first package adhesive (i.e., first package adhesive layer 300) containing a phosphor in the dam portion 110, and allowing at least a part or all of the phosphor to settle on the upper surface of the substrate 100 and / or the LED chip 200, specifically, settling the phosphor by a centrifugation process, and curing or semi-curing the first package adhesive layer 300 by a high-speed baking process.

[0047] After the first package adhesive layer 300 is cured or pre-cured (i.e., semi-cured), a second package adhesive layer 420 containing hollow particles is provided on top of the first package adhesive layer 300, and at least some or all of the hollow particles are gathered on the top of the second package adhesive layer 420 by heating, thereby forming a hollow particle gathering region 410.

[0048] In this embodiment, the hollow particles are glass microspheres with a hollow center, which have the characteristics of low density and light weight and gather in the upper region of the packaging adhesive when heated. They are transparent or translucent particles with a hollow structure and have reflective and refractive properties, so that the light directly above the lamp bead is reflected and refracted by the hollow particles, causing the light intensity in the center of the lamp bead to be refracted and reflected to both sides, improving the light intensity on both sides of the lamp bead.

[0049] In one embodiment, the second packaging adhesive layer 420 is silica gel. In the prior art shown in FIG. 7, the LED device is covered with a white adhesive 202 (hereinafter referred to as the white adhesive product), resulting in significant loss of light intensity above the LED device. In contrast, the present invention uses a combination of silica gel and hollow particles above the lamp beads (LED device). The hollow particles hang above the LED chip 200 and protrude above the LED device, improving brightness compared to the white adhesive product of the prior art. Furthermore, the light transmittance of the present silica gel is much higher than that of the transparent dam. Therefore, the luminous flux of the prior art white adhesive product is 30% lower than that of the product using hollow particles in the present invention at the same color point. Therefore, the LED device according to the present invention can relatively enhance the light intensity on both sides, increase the pitch of the lamp beads on the lamp panel, reduce the number of lamp beads on the same lamp panel, and reduce lamp bead costs. This improves the brightness of display products, enhances the user experience, and reduces application costs.

[0050] Specifically, according to the manufacturing method of this embodiment, it is preferable that the height of the first package adhesive layer 300 containing the phosphor provided within the dam portion 110 is lower than the top surface of the dam portion 110, so that the first package adhesive layer 300 does not come off the dam portion 110 when the phosphor is settled to the bottom by a centrifugation process, and the phosphor is covered on the top surface of the substrate 100 and the LED chip 200, and then the first package adhesive layer 300 can be hardened using a high-speed baking process in which the first package adhesive layer 300 is baked at 43°C for 30 to 40 minutes, and then baked at 130 to 150°C for 5 to 10 minutes.

[0051] A second package adhesive layer 420 containing hollow particles is provided on top of the first package adhesive layer 300, and then the hollow particles are gathered on top of the second package adhesive layer 420 by baking, forming a hollow particle gathering region 410. The baking conditions are as follows: baking at 43°C for 20-30 minutes, then heating to 100°C and baking for 10-30 minutes to release stress, and then baking at 150°C for 150-180 minutes to harden.

[0052] In the LED light-emitting device and manufacturing method according to the present invention, a phosphor is incorporated into the LED chip, and wavelength conversion is achieved by mixing the light emitted from the LED chip with the light excited by the phosphor, eliminating the need for a quantum dot film. Furthermore, the luminous intensity of the LED light-emitting device according to the present invention is higher than that of conventional technologies. In some applications, this eliminates the need for a DBEF film (brightness enhancement film) for secondary brightness enhancement, or even reduces the amount of DBEF film required. This offers advantages such as low cost, high brightness, and an ultra-wide viewing angle. Hollow particles have low density and light weight. When heated, they are concentrated in the area above the packaging adhesive. They have reflective and refractive properties, allowing light directly above the lamp bead to be reflected and refracted by the hollow particles, refracting and reflecting the light intensity in the center of the lamp bead to both sides, improving the light intensity on both sides of the lamp bead. Furthermore, because the hollow particles are transparent, they do not absorb the original light energy of the lamp bead, thereby improving the brightness around the lamp bead without significantly reducing the overall brightness of the lamp bead.

[0053] The LED light emitting device according to the embodiment of the present invention emits a large amount of peripheral light, resulting in the lighting effect shown in Figure 6b. In the prior art shown in Figure 7, the fluorescent adhesive 201 of the LED light emitting device 20 is covered with a white adhesive 202. However, the white adhesive significantly blocks light, resulting in only a small amount of light being emitted from the top of the LED light emitting device 20. The light transmission effect of the dam 203 is inferior to that of silica gel, resulting in little light being emitted from the sides of the dam 203 and poor lighting performance. Figure 8 shows the light intensity distribution of the LED light emitting device according to the embodiment, and Figure 9 shows the light intensity distribution of a prior art white adhesive product. The horizontal axis represents the light emission angle, and the vertical axis represents the light intensity (unit: cd, candela). As can be seen from the light intensity distributions of Figures 8 and 9, the light intensity distribution of the existing product shown in Figure 9, which is completely covered with white adhesive, is low on the sides (maximum value less than 1.6). The light intensity distribution curve in Figure 8 shows a slight depression in the center, with the maximum light intensity distributed on both sides of the normal line. The extreme values ​​of light intensity can reach 1.8 or more, thereby improving brightness uniformity and ensuring brightness uniformity even when the LED spacing is increased, meeting customer specifications. This reduces the number of LEDs used, achieving the goal of reducing application costs and improving application benefits. When designing a mini POB backlight module, the number of lamp beads can be reduced. As shown in Figure 12, the ratio of OD (optimal distance, i.e., the distance from the LED to the illuminated surface; in direct-type backlight modules, this is the distance between the diffuser plate and the top surface of the lamp panel PCB) to pitch (lamp bead pitch) can be increased to 1:1.6, reducing application costs.

[0054] The above are only preferred embodiments of the present invention, and do not limit the present invention. Any modifications, equivalent replacements, or improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An LED light emitting device, a mount, an LED chip, and a packaging adhesive layer; the mount has a substrate and a dam portion; the substrate has opposing front and back surfaces; the dam portion has a bottom surface and a top surface that face each other, the bottom surfaces of the LED chip and the dam portion are provided on the front surface of the substrate; the dam portion surrounds the LED chip and forms a chip mounting area used for mounting the LED chip and for placing the packaging adhesive layer, the packaging adhesive layer is packaged above the LED chip, the dam portion and the packaging adhesive layer are transparent or translucent, transparent or translucent hollow particles are provided on the top of the packaging adhesive layer, the height of the dam portion is the distance from the front surface of the substrate to the top surface of the dam portion, the height of the packaging adhesive layer protruding from the mount is the distance from the top surface of the dam portion to the tip of the packaging adhesive layer, and the height of the packaging adhesive layer protruding from the mount is greater than the height of the dam portion.

2. 2. The LED light-emitting device according to claim 1, wherein the outer surface of the packaging adhesive layer is curved, larger at the bottom and smaller at the top, the top of the packaging adhesive layer is located directly above the chip mounting area, and the hollow particles cover directly above the LED light-emitting device.

3. 2. The LED light-emitting device according to claim 1, wherein at least a portion of the packaging adhesive layer is not covered with the hollow particles, and the hollow particles cover at least a portion directly above the LED chip.

4. 3. The LED light-emitting device according to claim 2, wherein the projected area of ​​the region covered by the hollow particles on the bottom surface of the packaging adhesive layer accounts for 20 to 80% of the bottom surface area of ​​the packaging adhesive layer, or the thickness of the portion of the surface of the packaging adhesive layer that is not covered by the hollow particles is greater than at least the height of the dam portion.

5. The packaging adhesive layer includes a first packaging adhesive layer and a second packaging adhesive layer, The bottom of the first packaging adhesive layer is packaged on the front side of the substrate; the bottom of the second packaging adhesive layer is packaged on top of the first packaging adhesive layer; a phosphor is provided in the first package adhesive layer; a majority of the phosphor is located at the bottom of the first packaging adhesive layer; 2. The LED light emitting device according to claim 1, wherein a top surface of the first package adhesive layer is lower than a top surface of the dam portion.

6. 6. The LED light emitting device according to claim 5, wherein the mass content of the hollow particles in the second package adhesive layer is 1 to 5%.

7. 7. The LED light-emitting device according to claim 6, wherein the median diameter of the hollow particles is 15 μm to 100 μm.

8. 8. The LED light-emitting device according to claim 1, wherein a top surface of the dam portion is inclined inwardly of the dam portion.

9. A method for manufacturing an LED light-emitting device, comprising: The LED light-emitting device according to any one of claims 1 to 8 is manufactured using the method. manufacturing the mount and applying the packaging adhesive layer having the hollow particles to the mount; and making the height of the package adhesive layer protruding from the mount greater than the height of the mount.

10. The step of providing a packaging adhesive layer comprises: providing a first package adhesive containing a phosphor in the dam portion, then sedimenting the phosphor through a centrifugal process, and curing or semi-curing the first package adhesive through a high-speed baking process; 10. The method for manufacturing an LED light emitting device according to claim 9, further comprising the steps of: providing a second packaging adhesive containing the hollow particles above the first packaging adhesive; and baking the second packaging adhesive to cause the hollow particles to aggregate on top of the second packaging adhesive, thereby forming a hollow particle aggregation region.

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