LED lamp bead device and preparation method

Abstract

The invention discloses an LED lamp bead device and a preparation method thereof. The LED lamp bead device comprises a substrate, a driving chip and a light-emitting module, a plurality of bonding pads and a bonding pad circuit formed by a plurality of fan-out electrodes are arranged on the substrate; the plurality of bonding pads are divided into a first bonding pad area for placing a driving chip and a second bonding pad area for placing a light-emitting module; the first bonding pad area is provided with a plurality of pin bonding pads and a common-pole pin bonding pad, and the second bonding pad area is provided with a plurality of electrode bonding pads and a common-pole bonding pad; the plurality of pin bonding pads are electrically connected with the plurality of electrode bonding pads in a one-to-one correspondence manner; and the common electrode pin bonding pads and the common electrode bonding pads form common electrode pins based on the fan-out electrodes. The driving chip and the light-emitting module are integrated on the substrate, and the circuit arrangement and transfer steps of device packaging are reduced in cooperation with the light-emitting module based on the bonding pad circuit design of the substrate, so that the convenience of LED lamp bead device packaging is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of light-emitting devices, and in particular to an LED lamp bead device and a preparation method thereof. Background Art

[0002] With the development of miniaturized chip packaging technology, in the preparation process of display screen lamp bead devices, the packaging of LED lamp bead devices is mainly achieved through MIP (Mini / Micro LED in Package) packaging technology, using conductive adhesive to adhere the LED chip to the substrate, and then using packaging materials to package the LED chip on the substrate. The packaging material not only protects the chip from the influence of the external environment, but also provides good heat dissipation performance to ensure the stable operation of the LED chip.

[0003] Since the existing LED lamp bead devices require the red light chip, green light chip, blue light chip and driver chip to be placed on the substrate in sequence, the packaging operation is cumbersome and the chip transfer is prone to damage, which affects the packaging effect and the light output stability of the lamp bead device; and since multiple chips are integrated on the substrate, it is necessary to set a drive circuit on the substrate to realize the electrical connection of each chip, which leads to a complex internal circuit layout structure of the lamp bead device, affecting the convenience of packaging the lamp bead device. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art. The present invention provides an LED lamp bead device and a preparation method. By integrating a driving chip and a light-emitting module on a substrate, based on the pad circuit design of the substrate, and cooperating with the light-emitting module to reduce the circuit arrangement and transfer steps of the device packaging, the convenience of LED lamp bead device packaging is improved.

[0005] The present invention provides an LED lamp bead device, the LED lamp bead device comprising: a substrate, a driving chip and a light-emitting module;

[0006] The substrate is provided with a plurality of pads and a plurality of fan-out electrodes, and the plurality of pads and the plurality of fan-out electrodes cooperate to form a pad circuit;

[0007] The plurality of pads are divided into a first pad area for placing a driving chip and a second pad area for placing a light-emitting module;

[0008] The first pad area is provided with a plurality of pin pads and a common-pole pin pad, and the second pad area is provided with a plurality of electrode pads and a common-pole pad;

[0009] A plurality of the pin pads are electrically connected to a plurality of the electrode pads in a one-to-one correspondence, and the common-pole pin pad and the common-pole pad form a common-pole pin based on a fan-out electrode.

[0010] Furthermore, the second pad area is located in the middle area of ​​the substrate;

[0011] The first pad region is arranged at a side of the second pad region, and the first pad region is located at a side region close to one side of the substrate.

[0012] Furthermore, the light-emitting module comprises: a plurality of light-emitting chips arranged in a queue and a packaging glue layer filled between the plurality of light-emitting chips;

[0013] The thickness of the packaging glue layer is consistent with the thickness of the light-emitting chip. The light-emitting surface of the light-emitting chip is exposed on the top surface of the light-emitting module, and the bottom electrode of the light-emitting chip is exposed on the bottom surface of the light-emitting module.

[0014] Furthermore, the encapsulation glue layer includes transparent glue and reinforcing glue arranged in sequence along the light-emitting surface of the chip toward the bottom electrode;

[0015] The hardness of the transparent glue is smaller than the hardness of the reinforcing glue.

[0016] Furthermore, the thickness of the transparent adhesive is h0, the thickness of the light emitting chip is H, and the constraint relationship between h0 and H is: 0.5H≤h0<H.

[0017] Furthermore, the first pad area is also provided with an electrode pin pad, an input signal pad and an output signal pad;

[0018] The electrode pin pad forms an electrical electrode pin on the bottom surface of the substrate based on the fan-out electrode;

[0019] The input signal pads form input signal pins on the bottom surface of the substrate based on the fan-out electrodes, and the output signal pads form output signal pins on the bottom surface of the substrate based on the fan-out electrodes.

[0020] Furthermore, the substrate is provided with a plurality of rectangular grooves, the width of the rectangular grooves is w, and the value range of w is: 20 μm≤w≤30 μm;

[0021] The depth of the rectangular channel is h1, and the value range of h1 is: 20 μm≤h1≤30 μm.

[0022] Further, a plurality of the rectangular channels are located in the pads of the first pad region and the second pad region;

[0023] The distance between the rectangular channel and the edge of the pad is d, and the value range of d is 10 μm≤d≤15 μm.

[0024] Furthermore, the LED lamp bead device also includes a plastic packaging structure arranged on the substrate, and the plastic packaging structure includes a contrast layer covering the surface of the substrate, a reflective layer covering the surface of the contrast layer, and a plastic packaging layer arranged on the surface of the reflective layer;

[0025] The driving chip and the light-emitting module are encapsulated in the plastic packaging layer.

[0026] Furthermore, the contrast layer is made of one of epoxy resin, silica gel and silicone resin, and the contrast layer is doped with carbon powder.

[0027] Furthermore, the reflective layer is made of one of epoxy resin, silica gel and silicone resin, and the reflective layer is doped with at least one of titanium dioxide particles and zirconium oxide particles.

[0028] Furthermore, the material of the plastic sealing layer is one of UV glue, epoxy resin, silica gel and silicone resin.

[0029] The present invention also provides a method for preparing an LED lamp bead device, the method for preparing the LED lamp bead device comprising:

[0030] Prepare a light-emitting module, and connect a plurality of light-emitting chips based on packaging glue to form a light-emitting module;

[0031] Prepare a substrate, process and form a plurality of pads on the substrate, and divide the plurality of pads into a first pad area and a second pad area;

[0032] Placing and welding the driving chip in the first pad area, and placing and welding the light-emitting module in the second pad area;

[0033] The substrate, driver chip and light-emitting module are plastic-encapsulated to form an LED lamp bead device.

[0034] Furthermore, the preparation of the light-emitting module includes:

[0035] Setting a temporary substrate, and arranging a plurality of light-emitting chip arrays on the temporary substrate;

[0036] Filling the gaps formed by the plurality of light-emitting chips with transparent glue, so that the filling thickness of the transparent glue is more than half of the thickness of the chip;

[0037] Performing a dispensing operation of reinforcing glue on the surface of the transparent glue, so that the transparent glue and the reinforcing glue form a plastic sealing glue layer between the plurality of light-emitting chips;

[0038] Slicing a plurality of light-emitting chips based on laser cutting to form a plurality of light-emitting modules on a temporary substrate;

[0039] The temporary substrate is peeled off and several groups of light-emitting modules are placed on the adhesive film.

[0040] Further, placing the driving chip in the first pad area and placing the light emitting module in the second pad area includes:

[0041] Performing tin brushing on the steel mesh on the substrate so that the pad structures in the first pad area and the second pad area are coated with tin paste;

[0042] The driver chip is mounted on the first pad area, and the light-emitting module is mounted on the second pad area. After being furnace hardened, the die bonding and welding operations of the driver chip and the light-emitting module are realized.

[0043] Furthermore, the substrate, the driving chip and the light-emitting module are plastic-sealed to form an LED lamp bead device, which includes:

[0044] Filling a contrast layer on the surface of the substrate so that the contrast layer is filled between the driving chip and the light-emitting module, and curing the contrast layer by baking;

[0045] Filling the reflective layer on the surface of the contrast layer and curing it by baking;

[0046] The reflective layer is filled with UV glue for plastic sealing, thereby obtaining an LED lamp bead device. The present invention provides an LED lamp bead device and a preparation method, wherein a plurality of light-emitting chips are integrated and packaged into a light-emitting module, and the light-emitting module and the driving chip are integrated on the same substrate, thereby reducing the circuit arrangement of the LED package device, and the modular light-emitting module can reduce the machine turnover problem caused by the die bonding at the package end and reduce the undesirable situation of the ejector pin cracking, thereby improving the preparation efficiency of the LED lamp bead device. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0048] Figure 1 It is a schematic diagram of the structure of the LED lamp bead device in an embodiment of the present invention;

[0049] Figure 2 is a structural schematic diagram of a light-emitting module in an embodiment of the present invention;

[0050] Figure 3 is a schematic structural diagram of a pad circuit in an embodiment of the present invention;

[0051] Figure 4 is a schematic diagram of the bottom pin structure of the substrate in an embodiment of the present invention;

[0052] Figure 5 is a schematic diagram of the circuit arrangement of a display screen substrate in an embodiment of the present invention;

[0053] Figure 6 In the embodiment of the present invention, Figure 3 A schematic diagram of the structure at A;

[0054] Figure 7 It is a flow chart of a method for preparing an LED lamp bead device in an embodiment of the present invention;

[0055] Figure 8 Schematic diagram of the light emitting chip array arrangement structure in an embodiment of the present invention;

[0056] Fig. 9 is a schematic diagram of a transparent adhesive filling state in an embodiment of the present invention;

[0057] Fig.10 Schematic diagram of the state of plastic sealing with reinforced glue dot glue in the embodiment of the present invention;

[0058] Fig.11 Schematic diagram of laser cutting state in an embodiment of the present invention;

[0059] Fig.12 It is a schematic diagram of the light emitting module arrangement structure in an embodiment of the present invention. DETAILED DESCRIPTION

[0060] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0061] Embodiment 1:

[0062] Figure 1 The structure diagram of the LED lamp bead device in the embodiment of the present invention is shown. Figure 2The schematic diagram of the structure of the light-emitting module 5 in the embodiment of the present invention is shown, and the LED lamp bead device comprises: a substrate 1, a driving chip 6 and a light-emitting module 5, and the substrate 1 is provided with a plurality of pads and a plurality of fan-out electrodes 11, and the plurality of pads and the plurality of fan-out electrodes 11 cooperate to form a pad circuit. By integrating and packaging the light-emitting chip 52 into the light-emitting module 5, and integrating the driving chip 6 and the light-emitting module 5 on the pad circuit of the substrate 1, a lamp bead device with integrated lamp drive is formed, which can simplify the structural arrangement of the lamp bead device and the electrical connection circuit 83 of the display device, thereby improving the packaging efficiency of the lamp bead device and the convenience of the integrated packaging of the lamp bead device in the display device.

[0063] Figure 3 FIG. 1 shows a schematic diagram of the structure of a pad circuit in an embodiment of the present invention. Figure 4 A schematic diagram of the bottom pin structure of the substrate 1 in an embodiment of the present invention is shown, wherein a plurality of pads are divided into a first pad area 12 for placing a driver chip 6 and a second pad area 13 for placing a light-emitting module 5, the first pad area 12 is provided with a plurality of pin pads 125 and a common-pole pin pad 124, the second pad area 13 is provided with a plurality of electrode pads 131 and a common-pole pad 132, a plurality of the pin pads 125 are electrically connected to a plurality of the electrode pads 131 in a one-to-one correspondence, and the common-pole pin pad 124 and the common-pole pad 132 form a common-pole pin 18 based on the fan-out electrode 11.

[0064] Based on the first pad area 12 and the second pad area 13 formed by the pad circuit, the first pad area 12 can accommodate the driver chip 6, so that the driver chip 6 is directly placed in the first pad area 12, and the second pad area 13 can meet the die bonding requirements of the light-emitting module 5. Based on the pad circuit, the electrical connection between the driver chip 6 and the light-emitting module 5 can be achieved, thereby improving the convenience of the electrical connection between the driver chip 6 and the light-emitting module 5.

[0065] Specifically, the driving chip 6 is a flip chip, and the light-emitting module 5 is a flip-chip structure, so that when the driving chip 6 and the light-emitting module 5 are placed on the pad circuit of the substrate 1, the electrical connection between the driving chip 6 and the light-emitting module 5 can be achieved based on the pad circuit, and the flip-chip structure is coordinated with the pad circuit to reduce the wire bonding operation between the chips.

[0066] Specifically, the second pad area 13 is located in the middle area of ​​the substrate 1, so that the light-emitting module 5 is placed in the middle of the substrate 1, thereby ensuring that the packaged lamp bead device has good light output effect.

[0067] The first pad area 12 is arranged in a side area close to one side of the substrate 1. In this embodiment, the first pad area 12 is located in the 1 / 3 area on the left side of the substrate 1, ensuring that the driver chip 6 has sufficient installation position to meet the integrated packaging requirements of the driver chip 6 and the light-emitting module 5.

[0068] Specifically, the light-emitting module 5 includes: a plurality of light-emitting chips 52 arranged in a queue and a packaging glue layer 51 filled between the plurality of light-emitting chips 52, the plurality of light-emitting chips 52 include at least one red light chip, at least one green light chip and at least one blue light chip, and the red light chip, the green light chip and the blue light chip are arranged in a queue, that is, the plurality of light-emitting chips 52 are distributed at a preset spacing to ensure the uniformity of light output of the light-emitting module 5.

[0069] Furthermore, the packaging glue layer 51 is used to connect a plurality of the light-emitting chips 52 , so that the plurality of the light-emitting chips 52 are integrated and packaged to form a light-emitting module 5 .

[0070] Specifically, the thickness of the packaging glue layer 51 is consistent with the thickness of the light-emitting chip 52, the light-emitting surface of the light-emitting chip 52 is exposed on the top surface of the light-emitting module 5, and the bottom electrode of the light-emitting chip 52 is exposed on the bottom surface of the light-emitting module 5, so that the light-emitting surface and the bottom electrode of the light-emitting chip 52 are exposed, so that several light-emitting chips 52 are connected based on the packaging glue layer 51, and the chip electrode of the light-emitting chip 52 can be placed on the pad circuit of the substrate 1, and the light-emitting surface of the light-emitting chip 52 can be exposed, so that the light-emitting module 5 can be synchronously sealed with the driving chip 6 on the substrate 1, thereby improving the consistency of the plastic sealing of the lamp bead device.

[0071] Specifically, the packaging glue layer 51 includes a transparent glue 511 and a reinforcing glue 512 arranged in sequence along the light-emitting surface of the chip toward the bottom electrode. The hardness of the transparent glue 511 is less than the hardness of the reinforcing glue 512. Based on the reinforcing glue 512, the hardness of the packaging glue layer 51 of the light-emitting module 5 can be improved to facilitate the cutting process of the light-emitting module 5 and improve the overall structural stability of the light-emitting module 5.

[0072] Furthermore, the reinforcing glue 512 may be made of one of white glue, silica gel, epoxy resin and silicone resin. In the present embodiment, the reinforcing glue 512 is made of white glue doped with carbon powder, so that the white glue appears gray, thereby improving the light emission contrast of the light-emitting module 5 .

[0073] Furthermore, the thickness of the transparent glue 511 is h0, the thickness of the chip is H, and the constraint relationship between h0 and H is: 0.5H≤h0<H, that is, the thickness of the transparent glue 511 is not less than half of the thickness of the light-emitting chip 52, so that the transparent glue 511 can be bonded and connected to the light-emitting chip 52, and based on the transparent glue 511 blocking between the reinforcing glue 512 and the light-emitting chip 52, the reinforcing glue 512 is prevented from overflowing to the light-emitting surface of the light-emitting chip 52, thereby reducing the interference of the reinforcing glue 512 on the light-emitting effect of the light-emitting chip 52.

[0074] Specifically, the first pad area 12 is also provided with an electrode pin pad 123, an input signal pad 121 and an output signal pad 122. When the driver chip 6 is placed in the first pad area 12, the electrical electrodes of the driver chip 6 are correspondingly connected to the electrode pin pad 123, and the signal electrodes of the driver chip 6 are correspondingly placed on the input signal pad and the output signal pad, so that the driver chip 6 is connected to the pad circuit to meet the driving electrical connection requirements of the driver chip 6.

[0075] Furthermore, the electrode pin pad 123 forms an electrical electrode pin 17 on the bottom surface of the substrate 1 based on the fan-out electrode 11, the input signal pad 121 forms an input signal pin 16 on the bottom surface of the substrate 1 based on the fan-out electrode 11, and the output signal pad 122 forms an output signal pin 15 on the bottom surface of the substrate 1 based on the fan-out electrode 11, so that after the LED lamp bead device is packaged, it can be directly mounted on the working circuit of the external equipment, thereby meeting the use requirements of the LED lamp bead device.

[0076] Furthermore, the common pole pin 18, the electrical electrode pin 17, the input signal pin 16 and the output signal 15 are respectively distributed at the four corner positions of the bottom surface of the substrate 1, so that the arrangement spacing of each pin meets the mounting requirements of the working circuit, and the bottom surface of the substrate 1 is also provided with an identification mark 19. Based on the identification mark 19, it is convenient to carry out the alignment mounting of the LED lamp bead device and the working circuit, thereby improving the mounting accuracy and mounting efficiency of the LED lamp bead device.

[0077] Specifically, Figure 5The schematic diagram of the circuit arrangement of the display screen substrate in the embodiment of the present invention is shown. In this embodiment, the display screen substrate on which the LED lamp bead device is placed is provided with an arrangement circuit 8, and the arrangement circuit 8 includes a signal output circuit 81, a signal input circuit 82, a common pole circuit 84 and an electrical circuit 83, wherein the electrical settings of the common pole circuit 84 and the electrical circuit 83 are set according to the common pole design of the LED lamp bead device. When the LED lamp bead device is a common anode design, the common pole circuit 84 is a positive pole circuit, and the electrical circuit 83 is a negative pole circuit. When the LED lamp bead device is a common cathode design, the common pole circuit 84 is a negative pole circuit, and the electrical circuit 83 is a positive pole circuit.

[0078] Specifically, the signal output circuit 81, the signal input circuit 82, the common pole circuit 84 and the electrical circuit 83 are arranged in parallel with each other, and a lamp bead placement area is formed between the signal output circuit 81, the signal input circuit 82, the common pole circuit 84 and the electrical circuit 83. The connection ends derived from the signal output circuit 81, the signal input circuit 82, the common pole circuit 84 and the electrical circuit 83 are gathered in the middle position of the display screen substrate circuit, so that the LED lamp bead devices can be concentrated in the middle position of the circuit arrangement structure of the substrate 1, thereby improving the display effect of the display screen.

[0079] Furthermore, based on the driving chip 6 inside each LED lamp bead device, the signal output circuit 81 and the signal input circuit 82 of the display screen substrate cooperate to synchronously control and drive several LED lamp bead devices of the display screen, thereby improving the convenience of controlling multiple LED lamp bead devices in the display screen, and based on the arrangement structure of the signal output circuit 81 and the signal input circuit 82 of the display screen substrate, the circuit structure of the substrate 1 can be simplified.

[0080] Specifically, Figure 6 The embodiment of the present invention is shown in FIG. Figure 3 The enlarged schematic diagram of the structure at A shows that the substrate 1 is provided with a plurality of rectangular grooves 14, the width of the rectangular groove 14 is w, the value range of w is: 20μm≤w≤30μm, the depth of the rectangular groove 14 is h1, the value range of h1 is: 20μm≤h1≤30μm, and the setting position of the pad can be marked based on the rectangular groove 14.

[0081] Furthermore, several of the rectangular channels 14 are located in the pads of the first pad area 12 and the second pad area 13, and the distance between the rectangular channels 14 and the edge of the pad is d, and the value range of d is 10μm≤d≤15μm, so that a gap is formed between the pad and the channel 14, which can effectively prevent water vapor from extending to the position of the chip and solder paste, and reduce the situation where the solder paste flows into the substrate 1 and causes a short circuit in the pad line of the substrate 1.

[0082] Furthermore, the LED lamp bead device also includes a contrast layer 2 covering the surface of the substrate 1, and the contrast layer 2 is filled between the driving chip 6 and the light-emitting module 5. The contrast layer 2 is used to improve the light output effect of the LED lamp bead device.

[0083] Furthermore, the thickness of the contrast layer 2 is h2, and the value range of h2 is: 20μm≤h2≤30μm. The material of the contrast layer 2 is one of epoxy resin, silica gel and silicone resin, and the contrast layer is doped with carbon powder. In this embodiment, the material of the contrast layer 2 is epoxy resin, and carbon powder is doped in the epoxy resin to form a black colloid. The surface of the black colloid substrate 1 is coated to form the contrast layer 2, thereby improving the light output efficiency of the LED lamp bead device.

[0084] Specifically, the LED lamp bead device also includes a reflective layer 3 covering the surface of the contrast layer 2, the thickness of the reflective layer 3 is h3, and the value range of h3 is: 20μm≤h3≤30μm. Based on the reflective layer 3, the light of the light-emitting module 5 is reflected in the reflective layer 3 and then gathered at the light-emitting surface position to be emitted, thereby improving the luminous efficiency and light-emitting effect of the light source.

[0085] Furthermore, the material of the reflective layer 3 is one of epoxy resin, silica gel and silicone resin, and the reflective layer 3 is doped with at least one of titanium dioxide particles and zirconium oxide particles, so that the number of particles in the silica gel is increased to meet the reflection requirements of light.

[0086] Furthermore, the LED lamp bead device also includes a plastic sealing layer 4, the thickness of the plastic sealing layer 4 is h4, and the value range of h4 is: 60μm≤h4≤80μm. The material of the plastic sealing layer 4 is one of UV glue, epoxy resin, silica gel and silicone resin. In this embodiment, the material of the plastic sealing layer 4 is UV glue, and the LED lamp bead device is packaged as a whole based on UV glue to ensure the packaging effect of the LED lamp bead device.

[0087] The embodiment of the present invention provides an LED lamp bead device, which integrates a driver chip 6 and a light-emitting module 5 on a pad circuit of the same substrate 1 through LED packaging. Based on the pad circuit design of the substrate 1, the light-emitting module 5 is used to reduce the circuit arrangement and transfer steps of the device packaging, thereby improving the convenience of LED lamp bead device packaging.

[0088] Embodiment 2:

[0089] Figure 7 The flowchart of the preparation method of the LED lamp bead device in the embodiment of the present invention is shown, and the preparation method comprises:

[0090] S11: Prepare the light-emitting module 5.

[0091] A plurality of light emitting chips 52 are connected based on packaging glue to form a light emitting module 5, and the plurality of light emitting chips 52 are arranged in an array according to a preset arrangement order. The packaging glue layer 51 connects the plurality of light emitting chips 52 to form a light emitting module 5 structure, so as to transfer the light emitting module 5.

[0092] Specifically, the preparation of the light-emitting module 5 includes:

[0093] Figure 8 The schematic diagram of the arrangement structure of the light emitting chips 52 in an array in an embodiment of the present invention is shown. A temporary substrate 10 is provided, and a plurality of light emitting chips 52 are arranged in an array on the temporary substrate 10 .

[0094] The surface of the temporary substrate 10 is covered with a PET base film 20 , which may be a double-sided tape structure made of PET material. Based on the PET base film 20 , a plurality of light-emitting chips 52 are attached to the temporary substrate 10 .

[0095] Furthermore, the thickness of the temporary substrate 10 is set between 200μm and 300μm, and the thickness of the PET base film 20 is configured between 40μm and 60μm, so that the temporary substrate 10 can meet the support arrangement of several light-emitting chips 52, and the PET base film 20 can meet the bonding requirements of several light-emitting chips 52.

[0096] Furthermore, the polyethylene terephthalate (PET) substrate is a highly crystalline polymer material having good fatigue resistance, abrasion resistance and dimensional stability, and can be dissolved in organic chemicals to achieve rapid cleaning and removal.

[0097] An adhesive layer 30 is provided on the PET base film 20 . The thickness of the adhesive layer 30 is between 10 μm and 15 μm, which can meet the attachment arrangement of several light-emitting chips 52 . The light-emitting surface of the light-emitting chip 52 is attached to the adhesive layer 30 , so that the bottom electrode of the light-emitting chip 52 faces upward, so as to package and connect the light-emitting chip 52 on the temporary substrate 10 .

[0098] Furthermore, Fig. 9A schematic diagram of the filling state of the transparent glue 511 in the embodiment of the present invention is shown, in which the transparent glue 511 is filled in the gap formed by a plurality of light-emitting chips 52, so that the filling thickness of the transparent glue 511 is more than half of the chip thickness, and the transparent glue 511 is filled in the gap formed by a plurality of light-emitting chips 52, so that the glue layer thickness of the transparent glue 511 is more than half of the thickness of the light-emitting chip 52, and the glue layer thickness of the transparent glue 511 is less than the chip thickness of the light-emitting chip 52, and is formed into a transparent glue layer by hot air baking, and a plurality of light-emitting chips 52 are connected based on the transparent glue 511, and one end face of the glue layer formed by the transparent glue 511 can be flush with the light-emitting surface of the light-emitting chip 52, thereby ensuring the connection stability between the light-emitting chips 52 and ensuring that the light-emitting chip 52 has a good light-emitting effect.

[0099] Fig.10 It shows a schematic diagram of the state of plastic sealing by dispensing the reinforcing glue 512 in the embodiment of the present invention. Fig.11 A schematic diagram of the laser cutting state in an embodiment of the present invention is shown, in which a dispensing operation of a reinforcing glue 512 is performed on the surface of a transparent glue 511, so that the transparent glue 511 and the reinforcing glue 512 form a plastic sealing glue layer between a plurality of light-emitting chips 52, and by dispensing the reinforcing glue 512 on the surface of the transparent glue 511 and baking it with hot air, the reinforcing glue 512 can be filled between the plurality of light-emitting chips 52, and the thickness of the packaging glue layer 51 formed by the transparent glue 511 and the reinforcing glue 512 is flush with that of the light-emitting chip 52.

[0100] Furthermore, the hardness of the reinforcing glue 512 is greater than the hardness of the transparent glue 511 , so that the reinforcing glue 512 can increase the hardness of the packaging glue layer 51 , thereby improving the laser cutting reliability of the light-emitting module 5 .

[0101] A plurality of light emitting chips 52 are diced based on laser cutting to form a plurality of light emitting modules 5 on the temporary substrate 10 .

[0102] A plurality of chips connected based on the packaging glue layer 51 are placed in a laser cutting device, and are divided into a plurality of light-emitting modules 5 on a temporary substrate 10 by controlling the laser routing cutting. Any of the light-emitting modules 5 includes at least one red light chip, at least one green light chip and at least one blue light chip, so that a single light-emitting module 5 can meet the light display requirements.

[0103] Specifically, Fig.12A schematic diagram of the arrangement structure of the light-emitting module 5 in an embodiment of the present invention is shown. The temporary substrate 10 is stripped, and several groups of light-emitting modules 5 are placed on the adhesive film. The UV adhesive film 40 is covered on the bottom electrodes of several light-emitting modules 5, so that several light-emitting modules 5 are adhered to the UV adhesive film 40. The temporary substrate 10 is removed through a stripping process, so that several light-emitting modules 5 are separated from the temporary substrate 10 and arranged on the UV adhesive film 40.

[0104] Furthermore, in this embodiment, the UV adhesive film 40 can be formed on several light-emitting modules 5 by inverting the film, and the thickness of the UV adhesive film 40 is set between 30 μm and 40 μm, so that the UV adhesive film 40 can meet the attachment requirements of several light-emitting modules 5 .

[0105] S12: preparing a substrate 1.

[0106] A plurality of pads are formed on the substrate 1 , and the plurality of pads are divided into a first pad area 12 and a second pad area 13 .

[0107] A substrate 1 with a thickness of 80 μm to 120 μm is provided, a rectangular channel 14 is prepared on the substrate 1 by laser cutting or mechanical tool cutting, and a solder pad is arranged in the rectangular channel 14, so that a spacing of 10 μm to 15 μm is formed between the solder pad and the side wall of the rectangular channel 14, so that the driving chip 6 and the light-emitting module 5 are mounted on the substrate 1, which can reduce the risk of water vapor intruding into the chip connection position, thereby improving the packaging reliability of the LED lamp bead device.

[0108] S13: bonding the die and welding the driving chip 6 and the light-emitting module 5 .

[0109] The driver chip 6 is placed in the first pad area 12, the light-emitting module 5 is placed in the second pad area 13, and the steel mesh is brushed with tin on the substrate 1, so that the pad structures of the first pad area 12 and the second pad area 13 are coated with tin paste;

[0110] The driving chip 6 is mounted on the first pad area 12 , and the light emitting module 5 is mounted on the second pad area 13 . After being hardened in a furnace, the die bonding and welding operations of the driving chip 6 and the light emitting module 5 are completed.

[0111] S14: Plastic encapsulated components.

[0112] The substrate 1, the driving chip 6 and the light-emitting module 5 are plastic-sealed to form an LED lamp bead device. A contrast layer 2 is filled on the surface of the substrate 1 so that the contrast layer 2 is filled between the driving chip 6 and the light-emitting module 5, and is cured by baking. The contrast layer 2 is set to epoxy resin, and carbon powder is doped in the epoxy resin so that the contrast layer 2 forms a black glue layer, which can improve the light output efficiency of the LED lamp bead device.

[0113] Furthermore, the material of the contrast layer 2 may also be one of silica gel and silicone resin.

[0114] Furthermore, the thickness of the contrast layer 2 is set between 20μm and 30μm, which can meet the contrast improvement requirements of the LED lamp bead device, and the color of the contrast layer 2 is similar to the color of the reinforcement layer of the light-emitting module 5, thereby improving the packaging consistency of the LED lamp bead device and ensuring that the LED lamp bead device has good light output effect.

[0115] A reflective layer 3 is filled on the surface of the contrast layer 2 and cured by baking. The reflective layer 3 may be made of one of epoxy resin, silica gel and silicone resin. The reflective layer is doped with at least one of titanium dioxide particles and zirconium oxide particles to meet the reflection and convergence of the light emitted by the light-emitting module 5, thereby improving the light emission efficiency of the LED lamp bead device.

[0116] Specifically, UV glue is filled and covered on the reflective layer 3 for plastic sealing to obtain an LED lamp bead device. UV glue is filled on the substrate 1 so that the UV glue plastic seals the driving chip 6 and the light-emitting module 5. Based on UV light illumination, the UV glue forms a plastic sealing layer 4 on the substrate 1 to form an LED lamp bead device.

[0117] Furthermore, the material of the plastic sealing layer 4 can also be one of epoxy resin, silica gel and silicone resin to meet the plastic sealing packaging requirements of LED lamp bead devices.

[0118] Furthermore, a single lamp bead structure is obtained by cutting through a dicing process, and the single lamp bead structure can be adjusted according to the size requirements of the driving chip 6 and the light-emitting module 5, and the bottom pin size of the single lamp bead structure can be set according to actual electrical connection requirements.

[0119] In this embodiment, the bottom pin size of a single lamp bead structure is set to 1 / 4 of the length of a single lamp bead, meeting the driving and use requirements of the LED lamp bead device.

[0120] An embodiment of the present invention provides a method for preparing an LED lamp bead device, by integrating and packaging a plurality of light-emitting chips 52 into a light-emitting module 5, and by integrating the light-emitting module 5 and the driving chip 6 on the same substrate 1, the circuit arrangement of the LED packaged device is reduced. The modular light-emitting module 5 can reduce the machine turnover problem caused by the solid crystal at the package end and reduce the adverse condition of the ejector pin cracking, thereby improving the preparation efficiency of the LED lamp bead device.

[0121] In addition, the embodiments of the present invention are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. An LED lamp bead device, characterized in that: The LED lamp bead device comprises: a substrate, a driving chip and a light-emitting module; The substrate is provided with a plurality of pads and a plurality of fan-out electrodes, and the plurality of pads and the plurality of fan-out electrodes cooperate to form a pad circuit; The plurality of pads are divided into a first pad area for placing a driving chip and a second pad area for placing a light-emitting module; The first pad area is provided with a plurality of pin pads and a common-pole pin pad, and the second pad area is provided with a plurality of electrode pads and a common-pole pad; A plurality of the pin pads are electrically connected to a plurality of the electrode pads in a one-to-one correspondence, and the common-pole pin pad and the common-pole pad form a common-pole pin based on a fan-out electrode.

2. The LED lamp bead device according to claim 1, characterized in that: The second pad area is located in the middle area of ​​the substrate; The first pad region is arranged at a side of the second pad region, and the first pad region is located at a side region close to one side of the substrate.

3. The LED lamp bead device according to claim 1, characterized in that: The light-emitting module comprises: a plurality of light-emitting chips arranged in a queue and a packaging glue layer filled between the plurality of light-emitting chips; The thickness of the packaging glue layer is consistent with the thickness of the light-emitting chip. The light-emitting surface of the light-emitting chip is exposed on the top surface of the light-emitting module, and the bottom electrode of the light-emitting chip is exposed on the bottom surface of the light-emitting module.

4. The LED lamp bead device as claimed in claim 3, characterized in that: The encapsulation glue layer includes transparent glue and reinforcing glue arranged in sequence along the light-emitting surface of the chip and in the direction of the bottom electrode; The hardness of the transparent glue is smaller than the hardness of the reinforcing glue.

5. The LED lamp bead device as claimed in claim 4, characterized in that: The thickness of the transparent adhesive is h0, the thickness of the light emitting chip is H, and the constraint relationship between h0 and H is: 0.5H≤h0<H.

6. The LED lamp bead device according to claim 1, characterized in that: The first pad area is also provided with an electrode pin pad, an input signal pad and an output signal pad; The electrode pin pad forms an electrical electrode pin on the bottom surface of the substrate based on the fan-out electrode; The input signal pads form input signal pins on the bottom surface of the substrate based on the fan-out electrodes, and the output signal pads form output signal pins on the bottom surface of the substrate based on the fan-out electrodes.

7. The LED lamp bead device according to claim 1, characterized in that: The substrate is provided with a plurality of rectangular grooves, the width of the rectangular grooves is w, and the value range of w is: 20 μm≤w≤30 μm; The depth of the rectangular channel is h1, and the value range of h1 is: 20 μm≤h1≤30 μm.

8. The LED lamp bead device according to claim 7, characterized in that: A plurality of the rectangular channels are located in the pads of the first pad region and the second pad region; The distance between the rectangular channel and the edge of the pad is d, and the value range of d is 10 μm≤d≤15 μm.

9. The LED lamp bead device according to claim 1, characterized in that: The LED lamp bead device also includes a plastic packaging structure arranged on the substrate, and the plastic packaging structure includes a contrast layer covering the surface of the substrate, a reflective layer covering the surface of the contrast layer, and a plastic packaging layer arranged on the surface of the reflective layer; The driving chip and the light-emitting module are encapsulated in the plastic packaging layer.

10. The LED lamp bead device according to claim 9, characterized in that: The material of the contrast layer is one of epoxy resin, silica gel and silicone resin, and carbon powder is doped in the contrast layer.

11. The LED lamp bead device according to claim 9, characterized in that: The reflective layer is made of one of epoxy resin, silica gel and silicone resin, and the reflective layer is doped with at least one of titanium dioxide particles and zirconium oxide particles.

12. The LED lamp bead device according to claim 9, characterized in that: The material of the plastic sealing layer is one of UV glue, epoxy resin, silica gel and silicone resin.

13. A method for preparing an LED lamp bead device, characterized in that: The preparation method is used to prepare the LED lamp bead device according to any one of claims 1 to 12, and the preparation method comprises: Prepare a light-emitting module, and connect a plurality of light-emitting chips based on packaging glue to form a light-emitting module; Prepare a substrate, process and form a plurality of pads on the substrate, and divide the plurality of pads into a first pad area and a second pad area; Placing and welding the driving chip in the first pad area, and placing and welding the light-emitting module in the second pad area; The substrate, driver chip and light-emitting module are plastic-encapsulated to form an LED lamp bead device.

14. The method for preparing the LED lamp bead device according to claim 13, characterized in that: The preparation of the light-emitting module comprises: Setting a temporary substrate, and arranging a plurality of light-emitting chip arrays on the temporary substrate; Filling the gaps formed by the plurality of light-emitting chips with transparent glue, so that the filling thickness of the transparent glue is more than half of the thickness of the chip; Performing a dispensing operation of reinforcing glue on the surface of the transparent glue, so that the transparent glue and the reinforcing glue form a plastic sealing glue layer between the plurality of light-emitting chips; Slicing a plurality of light-emitting chips based on laser cutting to form a plurality of light-emitting modules on a temporary substrate; The temporary substrate is peeled off and several groups of light-emitting modules are placed on the adhesive film.

15. The method for preparing the LED lamp bead device according to claim 13, characterized in that: Placing the driving chip in the first pad area and placing the light emitting module in the second pad area comprises: Performing tin brushing on the steel mesh on the substrate so that the pad structures in the first pad area and the second pad area are coated with tin paste; The driver chip is mounted on the first pad area, and the light-emitting module is mounted on the second pad area. After being furnace hardened, the die bonding and welding operations of the driver chip and the light-emitting module are realized.

16. The method for preparing the LED lamp bead device according to claim 13, characterized in that: The step of plastic-sealing the substrate, the driver chip and the light-emitting module to form an LED lamp bead device comprises: Filling a contrast layer on the surface of the substrate so that the contrast layer is filled between the driving chip and the light-emitting module, and curing the contrast layer by baking; Filling the reflective layer on the surface of the contrast layer and curing it by baking; The reflective layer is filled and covered with UV glue for plastic sealing, thereby obtaining an LED lamp bead device.

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