LED lamp bead and packaging method and packaging system thereof

Abstract

The invention discloses an LED lamp bead and a packaging method and a packaging system thereof, and relates to the field of semiconductor photoelectric devices. The packaging method comprises the following steps: (1) fixing an LED chip in a bowl cup of a packaging bracket to obtain a first intermediate; (2) injecting first fluorescent glue into the bowl cup, and primarily curing to form a first fluorescent glue layer; the first fluorescent glue contains first fluorescent powder; (3) injecting second fluorescent glue on the first fluorescent glue layer, and primarily curing to form a second fluorescent glue layer to obtain a second intermediate; the second fluorescent glue contains second fluorescent powder; light colors generated by excitation of the first fluorescent powder and the second fluorescent powder are the same or different; (4) carrying out secondary curing on the first fluorescent glue layer and the second fluorescent glue layer in the second intermediate to form a fluorescent glue layer in the bowl cup; wherein the temperature of the primary curing is less than or equal to 110 DEG C, and the temperature of the secondary curing is more than or equal to 120 DEG C. According to the invention, the color coordinate concentration ratio of the LED lamp beads can be improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor optoelectronic devices, and in particular to an LED lamp bead and a packaging method and a packaging system thereof. Background Art

[0002] Existing white light lamp beads are composed of blue light LED chips, packaging brackets and fluorescent glue (packaging glue + red phosphor + green phosphor). The packaging process of this structure is: first fix the LED chip to the packaging bracket, and then apply the fluorescent glue (pre-mixed red phosphor + green phosphor + packaging glue) one by one or in rows through the electrode device, and then solidify to form a fluorescent glue layer. This packaging process has the following problems: 1. After applying the fluorescent glue, the fluorescent powder particles naturally settle and are unevenly distributed, resulting in discrete LED color coordinates and low concentration. 2. Since red light phosphor absorbs part of the green light, more green light phosphor is often used than red light phosphor, which makes the distribution uniformity of red light phosphor and green light phosphor worse after sedimentation, reducing the packaging yield. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide an LED lamp bead and a packaging method thereof, which can improve the color coordinate concentration of the LED lamp bead and optimize the light color.

[0004] Another technical problem to be solved by the present invention is to provide a packaging system for LED lamp beads, which can improve the color coordinate concentration of the LED lamp beads.

[0005] In order to solve the above problems, the present invention discloses a packaging method for LED lamp beads, which comprises:

[0006] (1) Fixing the LED chip in the bowl of the packaging bracket to obtain a first intermediate;

[0007] (2) injecting a first fluorescent glue into the bowl and preliminarily curing it to form a first fluorescent glue layer; the first fluorescent glue contains a first fluorescent powder;

[0008] (3) injecting a second fluorescent glue onto the first fluorescent glue layer, preliminarily curing the second fluorescent glue layer to obtain a second intermediate; the second fluorescent glue contains a second fluorescent powder; the light colors generated by the first fluorescent powder and the second fluorescent powder being excited are the same or different;

[0009] (4) secondary curing the first fluorescent adhesive layer and the second fluorescent adhesive layer in the second intermediate to form a fluorescent adhesive layer in the bowl;

[0010] Among them, the initial curing temperature is ≤110℃, and the secondary curing temperature is ≥120℃.

[0011] As an improvement of the above technical solution, step (4) includes:

[0012] (4.1) periodically repeating steps (2) and (3) at a preset thickness until the bowl is completely filled to obtain a second intermediate;

[0013] (4.2) secondary curing the first fluorescent adhesive layer and the second fluorescent adhesive layer in the second intermediate obtained in step (4.1);

[0014] The first phosphor and the second phosphor produce different colors of light when excited.

[0015] As an improvement of the above technical solution, step (2) includes:

[0016] (2.1) injecting a first fluorescent glue into the bowl and preliminarily curing it to form a first fluorescent glue layer;

[0017] (2.2) Repeat step (2.1) at least twice;

[0018] Step (3) includes:

[0019] (3.1) injecting a second fluorescent glue onto the first fluorescent glue layer and preliminarily curing the second fluorescent glue layer to form a second fluorescent glue layer;

[0020] (3.2) Repeat step (3.1) at least twice;

[0021] The first phosphor and the second phosphor produce different colors of light when excited.

[0022] As an improvement of the above technical solution, the thickness of the first fluorescent glue layer is 40-75 μm, the thickness of the second fluorescent glue layer is 40-75 μm; the thickness of the fluorescent glue layer is 400-600 μm.

[0023] As an improvement of the above technical solution, the second intermediate includes 4 to 5 first fluorescent glue layers and 4 to 5 second fluorescent glue layers.

[0024] As an improvement of the above technical solution, the LED chip is a blue LED chip, the first phosphor is a red phosphor, and the second phosphor is a green phosphor;

[0025] The temperature of the preliminary curing is 90-105°C and the duration is 20s-10min;

[0026] The secondary curing is performed at a temperature of 140 to 160° C. and for a duration of 2 to 5 hours.

[0027] Correspondingly, the present invention also discloses an LED lamp bead, which is obtained by packaging an LED chip through the above-mentioned LED lamp bead packaging method.

[0028] Correspondingly, the present invention also discloses a packaging system for LED lamp beads, which includes:

[0029] A die-bonding unit, used to fix the LED chip into the bowl of the packaging bracket to obtain a first intermediate;

[0030] The glue injection unit includes at least one first glue injection unit for injecting a first fluorescent glue into the bowl cup and at least one second glue injection unit for injecting a second fluorescent glue into the bowl cup; the first fluorescent glue contains a first fluorescent powder, and the second fluorescent glue contains a second fluorescent powder; the light colors generated by the excitation of the first fluorescent powder and the second fluorescent powder are the same or different;

[0031] A preliminary curing unit, used for preliminary curing the first fluorescent glue injected by the first glue injection unit to form a first fluorescent glue layer; and used for preliminary curing the second fluorescent glue injected by the second glue injection unit to form a second fluorescent glue layer; wherein the preliminary curing temperature is ≤110°C;

[0032] The curing unit is used for secondary curing the first fluorescent glue layer and the second fluorescent glue layer to form a fluorescent glue layer in the bowl; wherein the secondary curing temperature is ≥120°C.

[0033] As an improvement of the above technical solution, it also includes:

[0034] a blocking unit, comprising a first blocking unit and a second blocking unit;

[0035] The first blocking unit is provided with a first through hole corresponding to the bowl cup, so that the first fluorescent glue enters the bowl cup through the first through hole;

[0036] The second blocking unit is provided with a second through hole corresponding to the bowl cup, so that the second fluorescent glue enters the bowl cup through the second through hole.

[0037] As an improvement of the above technical solution, the packaging bracket includes a substrate and a plastic bracket, and the top of the plastic bracket forms a bowl;

[0038] The glue injection unit includes a plurality of glue injection nozzle groups arranged corresponding to the plastic bracket, and each glue injection nozzle group includes a first glue injection unit and a second glue injection unit.

[0039] The implementation of the present invention has the following beneficial effects:

[0040] The packaging method of the LED lamp beads in this embodiment forms a non-deformed but not completely cured first fluorescent glue layer and a second fluorescent glue layer through preliminary curing, and then forms a completely cured fluorescent glue layer through secondary curing. Based on this packaging method, the sedimentation of the first fluorescent powder / second fluorescent powder in the first fluorescent glue / second fluorescent glue during the packaging process can be greatly reduced, the distribution uniformity of the first fluorescent powder / second fluorescent powder can be optimized, and the color coordinate concentration and light color uniformity can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a flow chart of a method for packaging LED lamp beads in one embodiment of the present invention;

[0042] Figure 2 It is a schematic diagram of the structure of a packaging bracket and an LED chip in one embodiment of the present invention;

[0043] Figure 3 is an operation schematic diagram of step S2 in one embodiment of the present invention;

[0044] Figure 4 is an operation schematic diagram of step S3 in one embodiment of the present invention;

[0045] Figure 5 is a schematic diagram of a top view of the structure of a first shielding unit in one embodiment of the present invention;

[0046] Figure 6 This is a schematic diagram of the structure of an LED lamp bead in another embodiment of the present invention;

[0047] Figure 7 This is a schematic diagram of the structure of an LED lamp bead in another embodiment of the present invention;

[0048] Figure 8 is a schematic diagram of the composition of an LED packaging system in one embodiment of the present invention;

[0049] Fig. 9 This is the color coordinate distribution diagram of the LED lamp bead in Comparative Example 1 of the present invention;

[0050] Fig.10 is a color coordinate distribution diagram of the LED lamp bead in Example 1 of the present invention;

[0051] Fig.11 is a color coordinate distribution diagram of the LED lamp bead in Example 2 of the present invention;

[0052] Fig.12 is a color coordinate distribution diagram of the LED lamp bead in Example 3 of the present invention;

[0053] Fig.13 is a color coordinate distribution diagram of the LED lamp bead in Example 4 of the present invention;

[0054] In the figure, 1 is a crystal fixing unit, 2 is a glue injection unit, 21 is a first glue injection unit, 22 is a second glue injection unit, 3 is a preliminary curing unit, 4 is a curing unit, 5 is a blocking unit, 51 is a first blocking unit, 511 is a first through hole, 52 is a second blocking unit, 521 is a second through hole, 61 is an LED chip, 62 is a first fluorescent glue layer, 63 is a second fluorescent glue layer, 64 is a packaging bracket, 641 is a substrate, 642 is a plastic bracket, and 643 is a bowl. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and should not be construed as limiting the present application. In addition, it should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application.

[0056] In the description of the present application, it should be understood that the terms "length", "width", "up", "down", "left", "right", "horizontal", "top", "bottom", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0057] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0058] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0059] In the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0060] The disclosure below provides many different embodiments or examples to realize the different structures of the present application. In order to simplify the disclosure of the present application, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present application. In addition, the present application can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, and does not indicate the relationship between the various embodiments and / or settings discussed in itself. In addition, the various specific processes and examples of materials provided in the present application, but those of ordinary skill in the art can be aware of the application of other processes and / or the use scenarios of other materials.

[0061] See also Figure 1 An embodiment of the present invention provides a method for packaging an LED lamp bead, which comprises the following steps:

[0062] S1: Fixing the LED chip in the bowl of the packaging bracket to obtain a first intermediate;

[0063] S2: injecting a first fluorescent glue into the bowl and initially curing it to form a first fluorescent glue layer;

[0064] S3: injecting a second fluorescent glue onto the first fluorescent glue layer, and preliminarily curing the second fluorescent glue layer to obtain a second intermediate;

[0065] S4: secondary curing the first fluorescent adhesive layer and the second fluorescent adhesive layer in the second intermediate to form a fluorescent adhesive layer in the bowl;

[0066] The first fluorescent glue contains a first fluorescent powder, the second fluorescent glue contains a second fluorescent powder, the light colors generated by the first fluorescent powder and the second fluorescent powder are the same or different, the temperature of the initial curing is ≤110°C, and the temperature of the secondary curing is ≥120°C.

[0067] The packaging method of the LED lamp beads in this embodiment forms a non-deformed but not completely cured first fluorescent glue layer 62 and second fluorescent glue layer 63 through preliminary curing, and then forms a completely cured fluorescent glue layer through secondary curing. Based on this packaging method, the sedimentation of the first fluorescent powder / second fluorescent powder in the first fluorescent glue / second fluorescent glue during the packaging process can be greatly reduced, the distribution uniformity of the first fluorescent powder / second fluorescent powder can be optimized, and the color coordinate concentration and light color uniformity can be improved.

[0068] Specifically, the first phosphor and the second phosphor are phosphors that can be excited to produce monochromatic light, such as red phosphor, green phosphor or yellow-green phosphor; the first phosphor and the second phosphor can also be a mixture of at least two phosphors, for example, a mixture of red phosphor and green phosphor, but not limited thereto. Preferably, in some embodiments, the first phosphor is a red phosphor that can be excited to produce red light, and the second phosphor is a green phosphor that can be excited to produce green light. By setting the first fluorescent glue layer 62 containing red fluorescent powder at the bottom of the bowl 643 and setting the second fluorescent glue layer 63 containing green fluorescent powder above the first fluorescent glue layer 62, the absorption of green light by the red fluorescent powder can be reduced, thereby improving the brightness of the LED lamp beads.

[0069] Specifically, in some embodiments, the package bracket 64 may be a common SMD bracket in the art, which may be a frame structure composed of a metal substrate (such as Cu, Al, Cu / W, Cu / Mo, etc.) and a resin (such as PPA, epoxy resin, PBT, etc.), but is not limited thereto. Preferably, in some embodiments, see Figure 2 The packaging support 64 includes a substrate 641 and a plastic support 642, and a bowl 643 is provided on the top of the plastic support 642. The packaging support 64 with such a structure is convenient for forming the first fluorescent glue layer 62 and the second fluorescent glue layer 63 in steps at a later stage.

[0070] Specifically, the packaging method in this embodiment can be applied to the packaging of various types of LED chips 61. For example, from the perspective of packaging structure, it can be applied to flip-chip LED chips or face-mount LED chips; from the perspective of luminous light color, it can be applied to the packaging of blue LED chips, green LED chips, red LED chips, yellow LED chips, and purple LED chips, but is not limited thereto. Preferably, in some embodiments, the LED chip 61 is a blue LED chip.

[0071] Specifically, in step S1, the LED chip 61 can be fixed in the bowl 643 of the packaging bracket 64 by gluing, welding, etc., but not limited thereto. Preferably, in some embodiments, the LED chip 61 is first bonded to the bottom of the bowl 643 by insulating glue, and then the electrodes of the LED chip 61 are electrically connected to the substrate 641 by wires.

[0072] Specifically, in some embodiments, the first fluorescent glue is a mixture of the first fluorescent powder and an encapsulation resin. The encapsulation resin may be epoxy resin or silicone resin, but is not limited thereto. The first fluorescent powder accounts for 10 to 40 wt % in the first fluorescent glue.

[0073] Specifically, in step S2, the first fluorescent glue can be dotted into the bowl 643 by a conventional glue dot device, but is not limited thereto. Preferably, in some embodiments, see Figure 3 The first fluorescent glue is sprayed into the bowl cup 643 through the first glue injection unit 21 (glue injection nozzle) to form a highly uniform glue layer in a short time, and then the first fluorescent glue layer 62 is formed through preliminary curing to improve production efficiency. Furthermore, fluorescent glue can be sprayed into each bowl cup 643 through multiple parallel glue injection nozzles to further improve production efficiency.

[0074] Further, see Figure 3 , Figure 5 In order to achieve high-speed injection of the first fluorescent glue, a first blocking unit 51 is introduced between the packaging bracket 64 and the glue injection nozzle. The first blocking unit 51 is a plate-like structure and is provided with first through holes 511 corresponding to the bowl cup 643, so that the fluorescent glue enters the bowl cup 643 through the first through holes 511 without adhering to other positions.

[0075] Specifically, in step S2, the temperature of the initial curing is ≤ 110°C. The initial curing can prevent the first fluorescent glue from flowing, effectively preventing the first fluorescent powder from settling, and also improve the thickness control accuracy of the first fluorescent glue layer 62, optimizing the control of the color coordinate concentration. Preferably, in some embodiments, the temperature of the initial curing is 90-105°C, and the duration is 20s-10min.

[0076] Specifically, in step S2, preliminary curing can be achieved by baking equipment, but is not limited thereto. Preferably, in some embodiments, preliminary curing is achieved by heating with a heating plate that is substantially the same size as the package bracket 64. The heating plate can be attached to the bottom of the package bracket 64 to simplify the process.

[0077] Specifically, in step S3, the second fluorescent glue can be dotted onto the first fluorescent glue layer 62 in the bowl 643 by a conventional glue dot device, but is not limited thereto. Preferably, in some embodiments, see Figure 4The second fluorescent glue is sprayed into the bowl cup 643 by the second glue injection unit 22 (glue injection nozzle) to form a highly uniform glue layer in a short time, and then the second fluorescent glue layer 63 is formed by preliminary curing to improve production efficiency. Furthermore, fluorescent glue can be sprayed into each bowl cup 643 by multiple glue injection nozzles arranged in parallel to further improve production efficiency.

[0078] Specifically, in some embodiments, the second fluorescent glue is a mixture of the second fluorescent powder and an encapsulation resin. The encapsulation resin may be epoxy resin or silicone resin, but is not limited thereto. The second fluorescent powder accounts for 10 to 40 wt % in the second fluorescent glue.

[0079] Further, see Figure 4 In order to achieve high-speed injection of the second fluorescent glue, a second blocking unit 52 is introduced between the packaging bracket 64 and the glue injection nozzle. The second blocking unit 52 is a plate-like structure and is provided with second through holes 521 corresponding to the bowl cup 643, so that the fluorescent glue enters the bowl cup 643 through the second through holes 521 without adhering to other positions.

[0080] Specifically, in step S3, the temperature of the initial curing is ≤ 110°C. The initial curing can prevent the second fluorescent glue from flowing, effectively preventing the first fluorescent powder from settling, and also improve the thickness control accuracy of the second fluorescent glue layer 63, optimizing the control of the color coordinate concentration. Preferably, in some embodiments, the temperature of the initial curing is 90-105°C, and the duration is 20s-10min.

[0081] Specifically, in step S3, preliminary curing can be achieved by baking equipment, but is not limited thereto. Preferably, in some embodiments, preliminary curing is achieved by heating with a heating plate that is substantially the same size as the package bracket 64. The heating plate can be attached to the bottom of the package bracket 64 to simplify the process.

[0082] Specifically, in step S4, secondary curing is performed by a common baking device in the art, and the temperature of the secondary curing is ≥120° C., but not limited thereto. Preferably, in some embodiments, the temperature of the secondary curing is 140-160° C., and the duration is 2-5 hours.

[0083] Preferably, in some embodiments, step S2 comprises:

[0084] S21: injecting a first fluorescent glue into the bowl and initially curing it to form a first fluorescent glue layer;

[0085] S22: Repeat step S21 at least twice;

[0086] Step S3 includes:

[0087] S31: injecting a second fluorescent glue onto the first fluorescent glue layer, and preliminarily curing the second fluorescent glue layer to form the second fluorescent glue layer;

[0088] S32: Repeat step S31 at least twice;

[0089] Specifically, based on this embodiment, the first phosphor and the second phosphor produce different colors of light when excited. More specifically, the first phosphor is a red phosphor, and the second phosphor is a green phosphor.

[0090] Based on this implementation, the thickness of the single-layer first fluorescent glue layer 62 and the second fluorescent glue layer 63 can be further reduced, the sedimentation of the first fluorescent powder / the second fluorescent powder can be reduced, and the color coordinate concentration can be further optimized.

[0091] Specifically, see Figure 6 Based on this embodiment, the second intermediate may include 3 to 5 layers of the first fluorescent glue layer 62 and 3 to 5 layers of the second fluorescent glue layer 63. When the number of layers is too large, the production efficiency is reduced, and the thickness of the first fluorescent glue layer 62 and the second fluorescent glue layer 63 is too thin, resulting in uneven distribution in some places, reducing the uniformity of light color. Preferably, in some embodiments, the second intermediate includes 4 to 5 layers of the first fluorescent glue layer 62 and 4 to 5 layers of the second fluorescent glue layer 63.

[0092] Specifically, in this embodiment, the thickness of the first fluorescent glue layer 62 is 40-75 μm, the thickness of the second fluorescent glue layer 63 is 40-75 μm; the thickness of the fluorescent glue layer is 400-600 μm.

[0093] Preferably, in some other implementations, step S4 includes:

[0094] S41: periodically repeating step S2 and step S3 at a preset thickness until the bowl is completely filled to obtain a second intermediate;

[0095] S42: secondary curing the first fluorescent adhesive layer and the second fluorescent adhesive layer in the second intermediate obtained in step S41;

[0096] Based on this embodiment, firstly, the thickness of the first fluorescent glue layer 62 and the second fluorescent glue layer 63 can be further reduced, the sedimentation of the first fluorescent powder / the second fluorescent powder can be reduced, and the color coordinate concentration can be further optimized. Secondly, by using different types of first fluorescent powder and second fluorescent powder, the absorption of light can be greatly reduced, and the brightness of the LED lamp beads can be improved.

[0097] Specifically, based on this embodiment, the first phosphor and the second phosphor produce different colors of light when excited. More specifically, the first phosphor is a red phosphor, and the second phosphor is a green phosphor.

[0098] Specifically, see Figure 7 Based on this embodiment, the second intermediate may include 3 to 5 layers of the first fluorescent glue layer 62 and 3 to 5 layers of the second fluorescent glue layer 63. When the number of layers is too large, the production efficiency is reduced, and the thickness of the first fluorescent glue layer 62 and the second fluorescent glue layer 63 is too thin, resulting in uneven distribution in some places, reducing the uniformity of light color. Preferably, in some embodiments, the second intermediate includes 4 to 5 layers of the first fluorescent glue layer 62 and 4 to 5 layers of the second fluorescent glue layer 63.

[0099] Specifically, in this embodiment, the thickness of the first fluorescent glue layer 62 is 40-75 μm, the thickness of the second fluorescent glue layer 63 is 40-75 μm; the thickness of the fluorescent glue layer is 400-600 μm.

[0100] More preferably, in some embodiments, the ratio of the thickness of the first fluorescent glue layer 62 to the thickness of the second fluorescent glue layer 63 is 1:1.1 to 1:1.3. Based on this ratio, the color coordinate concentration can be further optimized to improve the brightness of the LED lamp beads.

[0101] Preferably, in some embodiments, the packaging method of the present invention further includes the steps of detection, color separation and light splitting, and taping commonly used in the art, but is not limited thereto.

[0102] Accordingly, see Figure 8 In another embodiment of the present invention, a packaging system for LED lamp beads is also disclosed, which includes: a crystal fixing unit 1, a glue injection unit 2, a preliminary curing unit 3 and a curing unit 4. The crystal fixing unit 1 is used to fix the LED chip 61 to the bowl cup 643 of the packaging bracket 64 to obtain a first intermediate. The glue injection unit 2 includes at least one first glue injection unit 21 for injecting a first fluorescent glue into the bowl cup 643 and at least one second glue injection unit 22 for injecting a second fluorescent glue into the bowl cup 643. The preliminary curing unit 3 is used to preliminarily cure the first fluorescent glue injected by the first glue injection unit 21 to form a first fluorescent glue layer 62; and to preliminarily cure the second fluorescent glue injected by the second glue injection unit 22 to form a second fluorescent glue layer 63; the curing unit 4 is used to secondary cure the first fluorescent glue layer 62 and the second fluorescent glue layer 63 to form a fluorescent glue layer in the bowl cup 643. The first fluorescent glue contains a first fluorescent powder, and the second fluorescent glue contains a second fluorescent powder; the light color generated by the excitation of the first fluorescent powder and the second fluorescent powder is the same or different;

[0103] Based on the packaging system of the LED lamp beads of this embodiment, the first fluorescent glue layer 62 and the second fluorescent glue layer 63 that are not deformed but not completely cured can be formed by preliminary curing, and then the completely cured fluorescent glue layer can be formed by secondary curing. Based on this packaging system, the sedimentation of the first fluorescent powder / second fluorescent powder in the first fluorescent glue / second fluorescent glue during the packaging process can be greatly reduced, the distribution uniformity of the first fluorescent powder / second fluorescent powder can be optimized, and the color coordinate concentration can be improved, thereby improving the uniformity of light color.

[0104] Specifically, the glue injection unit 2 can be a common glue dispensing device in the art, but is not limited thereto. Preferably, in some embodiments, the glue injection unit 2 includes a plurality of glue injection nozzle groups corresponding to the plastic bracket 642, and each glue injection nozzle group includes a first glue injection unit 21 (glue injection nozzle) and a second glue injection unit 22 (glue injection nozzle). Based on the glue injection unit 2, the injection of different fluorescent glues can be achieved by switching the glue injection unit 2, thereby improving the packaging efficiency.

[0105] Specifically, the preliminary curing unit 3 can be a common baking device in the art, but is not limited thereto. Preferably, in some embodiments, the preliminary curing unit 3 is a heating plate, which is substantially the same size as the packaging bracket 64. When in use, the heating plate can be attached to the bottom of the packaging bracket 64, thereby conveniently achieving preliminary curing.

[0106] Specifically, the curing unit 4 is a common baking device in the art, but is not limited thereto.

[0107] Preferably, in some embodiments, the LED packaging system further includes: a blocking unit 5, which includes a first blocking unit 51 and a second blocking unit 52; specifically, the first blocking unit 51 and the second blocking unit 52 are both plate-like structures, and the first blocking unit 51 is provided with a first through hole 511 corresponding to the bowl cup 643, so that the first fluorescent glue enters the bowl cup 643 through the first through hole 511; the second blocking unit 52 is provided with a second through hole 521 corresponding to the bowl cup 643, so that the second fluorescent glue enters the bowl cup 643 through the second through hole 521. Based on this embodiment, the first fluorescent glue and the second fluorescent glue can be quickly sprayed into the bowl cup 643 to form a first fluorescent layer and a second fluorescent layer with uniform thickness, thereby improving the packaging efficiency and the color coordinate concentration of the LED lamp beads. Specifically, the packaging efficiency of this embodiment can be improved by 20 to 35% compared with the packaging efficiency of the ordinary packaging method.

[0108] The present invention will be further described below with specific embodiments:

[0109] Example 1

[0110] This embodiment provides a method for packaging an LED lamp bead, comprising the following steps:

[0111] S1: Fixing an LED chip in a bowl of a packaging bracket to obtain a first intermediate; wherein the LED chip is a blue light LED chip;

[0112] S2: injecting a first fluorescent glue into the bowl and initially curing it to form a first fluorescent glue layer; wherein the first fluorescent glue is a red fluorescent glue; the initial curing temperature is 100° C. and the duration is 5 minutes; the thickness of the first fluorescent glue layer is 250 μm;

[0113] S3: injecting a second fluorescent glue onto the first fluorescent glue layer, and preliminarily curing the second fluorescent glue layer to obtain a second intermediate; wherein the second fluorescent glue is a green fluorescent glue; the preliminarily curing temperature is 100° C., and the curing time is 5 min; the thickness of the second fluorescent glue layer is 250 μm;

[0114] S4: secondary curing the first fluorescent adhesive layer and the second fluorescent adhesive layer in the second intermediate to form a fluorescent adhesive layer in the bowl; wherein the secondary curing temperature is 150° C. and the duration is 4 hours.

[0115] Example 2

[0116] This embodiment provides a method for packaging an LED lamp bead, comprising the following steps:

[0117] S1: Fixing an LED chip in a bowl of a packaging bracket to obtain a first intermediate; wherein the LED chip is a blue light LED chip;

[0118] S2: injecting the first fluorescent glue into the bowl, preliminarily curing to form a first fluorescent glue layer, and repeating 5 times; wherein the preliminarily curing temperature is 100°C, the duration is 30s; the thickness of each first fluorescent glue layer is 50μm;

[0119] S3: injecting a second fluorescent glue onto the first fluorescent glue layer, preliminarily curing to form a second fluorescent glue layer, repeating 5 times to obtain a second intermediate; wherein the second fluorescent glue is a green fluorescent glue; the preliminarily curing temperature is 100° C., the duration is 30 seconds; the thickness of each second fluorescent glue layer is 50 μm;

[0120] S4: secondary curing the first fluorescent adhesive layer and the second fluorescent adhesive layer in the second intermediate to form a fluorescent adhesive layer in the bowl; wherein the secondary curing temperature is 150° C. and the duration is 4 hours.

[0121] Example 3

[0122] This embodiment provides a method for packaging an LED lamp bead, comprising the following steps:

[0123] S1: Fixing an LED chip in a bowl of a packaging bracket to obtain a first intermediate; wherein the LED chip is a blue light LED chip;

[0124] S2: injecting a first fluorescent glue into the bowl and initially curing it to form a first fluorescent glue layer; wherein the initial curing temperature is 100° C. and the duration is 30 seconds; the thickness of the first fluorescent glue layer is 50 μm;

[0125] S3: injecting a second fluorescent glue onto the first fluorescent glue layer, and preliminarily curing the second fluorescent glue layer; wherein the second fluorescent glue is a green fluorescent glue; the preliminarily curing temperature is 100° C., and the duration is 30 seconds; the thickness of each second fluorescent glue layer is 50 μm;

[0126] S4: periodically repeat steps S2 and S3 5 times each to obtain a second intermediate;

[0127] S5: secondary curing the first fluorescent adhesive layer and the second fluorescent adhesive layer in the second intermediate to form a fluorescent adhesive layer in the bowl; wherein the secondary curing temperature is 150° C. and the duration is 4 hours.

[0128] Example 4

[0129] This embodiment provides a packaging method for LED lamp beads, which differs from Embodiment 3 in that the thickness of the first fluorescent glue layer is 50 μm, and the thickness of the second fluorescent glue layer is 60 μm.

[0130] Comparative Example 1

[0131] This comparative example provides a packaging method for LED lamp beads, which differs from Example 1 in that red phosphor, green phosphor and resin are mixed simultaneously to form fluorescent glue, which is then dispensed and cured.

[0132] The LED lamp beads obtained in Examples 1 to 4 and the comparative example were tested. Specifically, the test current was 65 mA and the test voltage was 2.7 V. The specific test results are shown in the following table:

[0133] Brightness / lm Color coordinate concentration Example 1 42.6 87％ Example 2 43.5 95％ Example 3 44.1 96％ Example 4 44.6 97％ Comparative Example 1 42.4 83％

[0134] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means 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 application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0135] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A method for packaging LED lamp beads, characterized in that: include: (1) Fixing the LED chip in the bowl of the packaging bracket to obtain a first intermediate; (2) injecting a first fluorescent glue into the bowl and preliminarily curing it to form a first fluorescent glue layer; the first fluorescent glue contains a first fluorescent powder; (3) injecting a second fluorescent glue onto the first fluorescent glue layer, preliminarily curing the second fluorescent glue layer to obtain a second intermediate; the second fluorescent glue contains a second fluorescent powder; the light colors generated by the first fluorescent powder and the second fluorescent powder being excited are the same or different; (4) secondary curing the first fluorescent adhesive layer and the second fluorescent adhesive layer in the second intermediate to form a fluorescent adhesive layer in the bowl; Among them, the temperature of primary curing is ≤110°C, and the temperature of secondary curing is ≥120°C.

2. The LED lamp bead packaging method according to claim 1, characterized in that: Step (4) comprises: (4.1) periodically repeating steps (2) and (3) at a preset thickness until the bowl is completely filled to obtain a second intermediate; (4.2) secondary curing the first fluorescent adhesive layer and the second fluorescent adhesive layer in the second intermediate obtained in step (4.1); The first phosphor and the second phosphor produce different colors of light when excited.

3. The LED lamp bead packaging method according to claim 1, characterized in that: Step (2) comprises: (2.1) injecting a first fluorescent glue into the bowl and preliminarily curing it to form a first fluorescent glue layer; (2.2) Repeat step (2.1) at least twice; Step (3) includes: (3.1) injecting a second fluorescent glue onto the first fluorescent glue layer and preliminarily curing the second fluorescent glue layer; (3.2) Repeat step (3.1) at least twice; The first phosphor and the second phosphor produce different colors of light when excited.

4. The LED lamp bead packaging method according to claim 2 or 3, characterized in that: The thickness of the first fluorescent glue layer is 40-75 μm, the thickness of the second fluorescent glue layer is 40-75 μm; the thickness of the fluorescent glue layer is 400-600 μm.

5. The LED lamp bead packaging method according to claim 2 or 3, characterized in that: The second intermediate includes 4 to 5 first fluorescent glue layers and 4 to 5 second fluorescent glue layers.

6. The LED lamp bead packaging method according to any one of claims 1 to 3, characterized in that: The LED chip is a blue LED chip, the first phosphor is a red phosphor, and the second phosphor is a green phosphor; The temperature of the preliminary curing is 90-105°C and the duration is 20s-10min; The secondary curing is performed at a temperature of 140 to 160° C. and for a duration of 2 to 5 hours.

7. An LED lamp bead, characterized in that: The LED chip is packaged by the LED lamp bead packaging method according to any one of claims 1 to 6.

8. A packaging system for LED lamp beads, characterized in that: include: A die-bonding unit, used to fix the LED chip into the bowl of the packaging bracket to obtain a first intermediate; The glue injection unit includes at least one first glue injection unit for injecting a first fluorescent glue into the bowl cup and at least one second glue injection unit for injecting a second fluorescent glue into the bowl cup; the first fluorescent glue contains a first fluorescent powder, and the second fluorescent glue contains a second fluorescent powder; the light colors generated by the excitation of the first fluorescent powder and the second fluorescent powder are the same or different; A preliminary curing unit, used for preliminarily curing the first fluorescent glue injected by the first glue injection unit to form a first fluorescent glue layer; and for preliminarily curing the second fluorescent glue injected by the second glue injection unit to form a second fluorescent glue layer; wherein the temperature of the preliminarily curing is ≤110° C.; The curing unit is used for secondary curing the first fluorescent glue layer and the second fluorescent glue layer to form a fluorescent glue layer in the bowl; wherein the secondary curing temperature is ≥120°C.

9. The LED lamp bead packaging system as claimed in claim 8, characterized in that: Also includes: a blocking unit, comprising a first blocking unit and a second blocking unit; The first blocking unit is provided with a first through hole corresponding to the bowl cup, so that the first fluorescent glue enters the bowl cup through the first through hole; The second blocking unit is provided with a second through hole corresponding to the bowl cup, so that the second fluorescent glue enters the bowl cup through the second through hole.

10. The LED lamp bead packaging system as claimed in claim 8, characterized in that: The packaging bracket includes a substrate and a plastic bracket, and the top of the plastic bracket forms a bowl; The glue injection unit includes a plurality of glue injection nozzle groups arranged corresponding to the plastic bracket, and each glue injection nozzle group includes a first glue injection unit and a second glue injection unit.

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