CHIP LED packaging structure and packaging method

Abstract

The invention discloses a CHIP LED packaging structure and a packaging method. The packaging structure comprises a substrate, an LED light-emitting unit and a packaging adhesive layer. The front surface of the substrate is provided with a front surface circuit, the back surface of the substrate is provided with a back surface circuit, the substrate is provided with a through hole penetrating through the front surface and the back surface of the substrate, and the front surface circuit and the back surface circuit are electrically connected through the through hole; the front circuit comprises a plurality of die bonding areas and a wire bonding area, the plurality of die bonding areas are arranged at intervals, and a first ink layer is arranged between every two adjacent die bonding areas; the LED light-emitting unit comprises a plurality of LED chips, and the LED chips are fixed on the die bonding area and are electrically connected with the wire bonding area; and the packaging adhesive layer at least covers the LED chip. According to the invention, the light-emitting brightness, the light-emitting angle and the reliability of the lamp bead can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of LED packaging, and in particular to a CHIP LED packaging structure and a packaging method. Background Art

[0002] As LED displays develop towards high definition, full high definition, and ultra-high definition, the market has put forward higher requirements for LED display screens in terms of anti-collision, luminous brightness, luminous angle, reliability, etc. LED lamp beads are one of the important components of LED displays and significantly affect the performance of LED displays.

[0003] In the packaging process of existing small-pitch LED lamp beads, the distance between multiple LED chips is small, which easily leads to mutual influence between LED chips and reduces the performance of LED lamp beads. In particular, when the LED chips are bonded to the substrate, the problem of glue throwing will cause conduction between LED chips. In addition, the contact area between the packaging glue layer and the insulating area of ​​the substrate is reduced, which will also make it easier for water vapor to enter the interior of the LED lamp bead, reducing the reliability of the LED lamp bead. Therefore, it is necessary to reasonably design the packaging structure and packaging method to ensure the stability and reliability of the LED lamp bead. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a CHIP LED packaging structure and a packaging method to improve the reliability of the CHIP LED packaging structure.

[0005] In order to solve the above problems, the present invention discloses a CHIP LED packaging structure, including a substrate, an LED light-emitting unit and a packaging adhesive layer;

[0006] The front side of the substrate is provided with a front circuit, the back side of the substrate is provided with a back circuit, the substrate is provided with a through hole penetrating the front side and the back side of the substrate, the front circuit and the back circuit are electrically connected through the through hole; the front circuit includes a plurality of die-bonding areas and wire bonding areas, the plurality of die-bonding areas are arranged at intervals, and a first ink layer is provided between adjacent die-bonding areas;

[0007] The LED light-emitting unit includes a plurality of LED chips, and the LED chips are fixed on the die-bonding area and are electrically connected to the wire-bonding area;

[0008] The packaging adhesive layer at least covers the LED chip.

[0009] As an improvement of the above technical solution, the opening area of ​​the upper surface of the through hole is smaller than the opening area of ​​the lower surface;

[0010] Conductive metal is arranged in the through hole, and the conductive metal is electrically connected to the front circuit and the back circuit respectively.

[0011] As an improvement of the above technical solution, the side wall of the through hole and the back surface of the substrate have a preset angle, and the preset angle is 105° to 135°;

[0012] The cross section of the substrate is rectangular, and the through holes are arranged on the four corners of the substrate.

[0013] As an improvement of the above technical solution, the edge of the front side of the substrate is an isolation area, and a second ink layer is provided on the isolation area;

[0014] The minimum distance between the edge of the second ink layer and the edge of the substrate is 50 μm to 250 μm; and / or,

[0015] The thickness of the second ink layer is 10 μm to 50 μm; and / or,

[0016] The minimum distance between the edge of the first ink layer and the edge of the crystal-bonding area is 30 μm to 180 μm; and / or,

[0017] The thickness of the first ink layer is 10 μm to 50 μm.

[0018] As an improvement of the above technical solution, the back circuit includes a plurality of functional pins, and the ratio of the area of ​​each functional pin to the area of ​​the back side of the substrate is (0.04-0.12):1.

[0019] As an improvement of the above technical solution, the encapsulation glue layer covers the LED chip and the substrate;

[0020] The side of the packaging glue layer above each LED chip facing away from the substrate is convex.

[0021] As an improvement of the above technical solution, the solid crystal region includes a first solid crystal region, a second solid crystal region and a third solid crystal region, and the wire bonding region includes a first wire bonding region, a second wire bonding region, a third wire bonding region, a fourth wire bonding region and a fifth wire bonding region;

[0022] The first solid crystal region, the second solid crystal region and the third solid crystal region are arranged in a straight line; the first welding wire region, the second welding wire region, the third welding wire region, the fourth welding wire region and the fifth welding wire region are arranged clockwise around the solid crystal region, and the first welding wire region and the second welding wire region are arranged on one side of the solid crystal region, and the third welding wire region, the fourth welding wire region and the fifth welding wire region are arranged on the other side of the solid crystal region.

[0023] As an improvement of the above technical solution, the LED chip includes a first chip, a second chip and a third chip;

[0024] The first chip is fixed on the first die-bonding area and is electrically connected to the first die-bonding area and the fifth welding area, respectively; the second chip is fixed on the second die-bonding area and is electrically connected to the first wire bonding area and the fourth wire bonding area, respectively; and the third chip is fixed on the third die-bonding area and is electrically connected to the second wire bonding area and the third wire bonding area, respectively.

[0025] As an improvement of the above technical solution, the back side circuit includes a first function pin, a second function pin, a third function pin and a fourth function pin;

[0026] The first welding wire area is electrically connected to the first functional pin through an electroplated lead, the second welding wire area is electrically connected to the second functional pin through an electroplated lead, the third welding wire area, the fourth welding wire area and the fifth welding wire area are interconnected through electroplated leads, and the third welding area is electrically connected to the third functional pin through an electroplated lead, and the first die-bonding area is electrically connected to the fourth functional pin through an electroplated lead.

[0027] Correspondingly, the present invention also discloses a CHIP LED packaging method for obtaining the above-mentioned CHIP LED packaging structure, comprising the following steps:

[0028] A front circuit is arranged on the front side of the substrate, and a back circuit is arranged on the back side of the substrate; wherein the front circuit includes a plurality of die-bonding areas and wire-bonding areas;

[0029] Filling the through hole of the substrate with conductive metal so that the front circuit and the back circuit are electrically connected;

[0030] Forming a first ink layer between adjacent solid crystal regions; Printing an ink composition on the substrate between adjacent solid crystal regions to form a first ink layer, wherein the viscosity of the ink composition at 25° C. is 5 mPa·s to 15 mPa·s; and / or the surface tension of the ink composition is 25 mN / m to 55 mN / m;

[0031] Fixing the LED chip on the die-bonding area, and electrically connecting the LED chip to the wire-bonding area;

[0032] A packaging glue layer is provided on the LED chip.

[0033] As an improvement of the above technical solution, the encapsulation glue layer provided on each LED chip is molded to form a protrusion through a molding process.

[0034] The implementation of the present invention has the following beneficial effects:

[0035] In the CHIP LED packaging structure provided by the present invention, the die-bonding areas of different chips are arranged at intervals and isolated by the first ink layer, which can avoid the quality reduction or even failure of the LED chips due to the reasons such as glue throwing during the manufacturing process, and improve the yield rate of the lamp beads. The setting of the first ink layer can also improve the display contrast of the lamp beads, and correspondingly reduce the proportion of black powder added to the packaging glue layer, thereby improving the brightness of the lamp beads. In addition, the contact area between the packaging glue layer and the substrate is increased, and the external water vapor is not easy to enter the interior of the LED chip, thereby improving the overall airtightness of the lamp beads. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a schematic diagram of the front structure of a CHIP LED package structure provided by an embodiment of the present invention;

[0037] Figure 2 is a schematic diagram of the back structure of a CHIP LED package structure provided by an embodiment of the present invention;

[0038] Figure 3 yes Figure 1 AA surface section view;

[0039] Figure 4 is a schematic diagram of the front structure of a substrate provided by an embodiment of the present invention;

[0040] Figure 5 It is a schematic diagram of the front structure of the substrate provided by an embodiment of the present invention after the first ink layer and the second ink layer are formed. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in further detail below.

[0042] like Figure 1 to Figure 5 As shown, the present invention provides a CHIP LED packaging structure, including a substrate 1, an LED light-emitting unit and a packaging adhesive layer 3.

[0043] Specifically, a front circuit 11 is provided on the front side of the substrate 1, a back circuit 12 is provided on the back side of the substrate 1, a through hole 14 is provided on the substrate 1 which penetrates the front and back sides of the substrate, and the front circuit 11 and the back circuit 12 are electrically connected through the through hole 14; the front circuit 11 includes a plurality of solid crystal areas 111 and welding wire areas 112, the plurality of solid crystal areas 111 are arranged at intervals, and a first ink layer 13 is provided between adjacent solid crystal areas 111.

[0044] The LED light emitting unit includes a plurality of LED chips 21 . The LED chips 21 are fixed on the die-bonding area 111 and are electrically connected to the wire-bonding area 112 .

[0045] The packaging adhesive layer 3 at least covers the LED chip 21 .

[0046] In the CHIP LED packaging structure provided by the present invention, the solid crystal regions 111 of different chips are arranged at intervals and isolated by the first ink layer 13. In the small-pitch LED device, the distance between different LED chips 21 is relatively close. The glue-spinning phenomenon generated by the solid crystal glue during the solid crystal process will cause the quality of the LED chip 21 to be reduced or even fail. The solid crystal regions 111 are arranged at intervals and the first ink layer 13 is arranged thereon, which can reduce the probability of glue-spinning and glue-climbing phenomena. Moreover, the setting of the dark first ink layer 13 can also improve the display contrast of the lamp beads, and correspondingly reduce the addition ratio of black powder in the encapsulation glue layer 3, thereby improving the brightness of the lamp beads. In addition, the contact area between the encapsulation glue layer 3 and the substrate 1 is increased, and the combination between the two is more firm and reliable. It is not easy for external water vapor to enter the interior of the LED chip 21, thereby improving the overall air tightness of the lamp beads.

[0047] In one embodiment, the substrate 1 is a BT resin substrate, which has good copper coating effect and is widely used as a substrate material. The material of the encapsulation adhesive layer 3 can be one or more of epoxy resin, polyurethane resin, and silicone resin.

[0048] In one embodiment, the minimum spacing between adjacent LED chips 21 is 200 μm to 300 μm. In existing small-pitch LED devices, the distance between adjacent LED chips 21 is relatively close. Due to the difference in heights of different LED chips 21, the light emitted by the LED chip 21 with a smaller height will be partially blocked by the adjacent LED chip 21 with a larger height, resulting in asymmetric light-emitting angles of different LED chips 21. The present invention increases the distance between adjacent LED chips 21, which is conducive to reducing the influence of the setting of the LED chip 21 on the light-emitting angle.

[0049] In a preferred embodiment, the opening area of ​​the upper surface of the through hole 14 is smaller than the opening area of ​​the lower surface to form a through hole 14 with an inclined side wall. The through hole of the existing lamp bead structure is a straight through hole, the heat dissipation capacity of the lamp bead is poor, and water vapor easily invades the inside of the lamp bead, causing the lamp bead to fail. The opening area of ​​the upper surface of the through hole 14 of the present invention is smaller than the opening area of ​​the lower surface, which can increase the heat dissipation capacity of the lamp bead, and the heat generated by the LED chip 21 can be better dissipated from the back of the substrate 1; the inclined through hole can also increase the difficulty of water vapor entering the front circuit 11 of the substrate 1 along the through hole 14, thereby reducing the problem of lamp bead failure caused by water vapor infiltrating the inside of the lamp bead. More preferably, in one embodiment, the angle α between the side wall of the through hole 14 and the back of the substrate 1 is 105° to 135°, exemplarily 110°, 115°, 120°, 125° or 130°, but not limited to this. If the angle is too small, the water vapor blocking effect is not great; if the angle is too large, the back surface area of ​​the substrate 1 will be reduced, which is not conducive to the reasonable arrangement of the back surface circuit 12.

[0050] In a preferred embodiment, the cross section of the substrate 1 is rectangular, and the through holes 14 are arranged on the four corners of the substrate 1. The through holes 14 arranged on the corners are a common hole structure shared by multiple substrates 1, which reduces the preparation process and improves production efficiency. Conductive metal is provided in the through hole 14, and the conductive metal is electrically connected to the front line 11 and the back line 12 respectively, so as to realize the interconnection between the front line 11 and the back line 12. The conductive metal can be copper, aluminum, silver, etc., which is not specifically limited here. The conductive metal forms a conductive metal column in the through hole 14. The inclined sidewall can reduce the risk of fracture of the conductive metal column filled in the through hole 14 and increase the strength of the through hole 14.

[0051] In one embodiment, in addition to the first ink layer 13, a second ink layer 15 is further provided on the substrate 1, and the edge of the front side of the substrate 1 is an isolation area, and the second ink layer 15 is provided on the isolation area. Preferably, the second ink layer 15 also covers the upper surface of the conductive metal column in the through hole 14. The provision of the second ink layer 15 can prevent different light-emitting units from being accidentally connected together due to impurities and the like during the packaging process to form string lighting or short circuit problems, and can also play a good insulating role, reduce the probability of ion migration between light-emitting units, ensure the normal use of LED devices, and avoid failure of LED devices.

[0052] Preferably, the minimum distance S1 between the edge of the second ink layer 15 and the edge of the substrate 1 is 50 μm to 250 μm, so as to form a second ink layer 15 of sufficient width to improve the reliability of each light-emitting unit. The minimum distance S2 between the edge of the first ink layer 13 and the edge of the solid crystal region 111 is 100 μm to 300 μm, so as to ensure the insulation isolation effect of different solid crystal regions 111, and at the same time, there is a sufficient contact area between the encapsulation glue layer 3 and the substrate 1, so as to improve the bonding ability between the encapsulation glue layer 3 and the substrate 1.

[0053] In one embodiment, the thickness of the first ink layer 13 is 10 μm to 50 μm, and the thickness of the second ink layer 15 is 10 μm to 50 μm. Preferably, the thickness of the first ink layer 13 is the same as that of the second ink layer 15 .

[0054] It is understandable that the first ink layer 13 and the second ink layer 15 may use the same or different ink compositions. Specifically, the ink composition includes a resin, a curing agent and a filler. Among them, the resin may be an epoxy resin, the curing agent may be an amine curing agent, and the filler may be a green pigment. In order to ensure the contact area between the encapsulation glue layer 3 and the substrate 1, the first ink layer 13 and / or the second ink layer 15 of the present invention are obtained by inkjet printing. The ink composition has a certain fluidity to achieve inkjet printing, and at the same time will not climb to the solid crystal area and the welding line area, so that a sufficient area of ​​the substrate 1 is exposed to achieve a close combination with the encapsulation glue layer 3. In a preferred embodiment, the viscosity of the ink composition forming the first ink layer at 25°C is 5mPa·s~15mPa·s; and / or the surface tension of the ink composition forming the first ink layer is 25mN / m~55mN / m, the viscosity and / or surface tension of the ink composition forming the second ink layer may be less than the ink composition forming the first ink layer. In order to improve the encapsulation efficiency, the first ink layer 13 and the second ink layer 15 use the same ink composition.

[0055] The back circuit 12 of the substrate 1 includes a plurality of functional pins 121, and the ratio of the area of ​​each functional pin 121 to the area of ​​the back of the substrate 1 is (0.04-0.12):1, and is 0.05:1, 0.07:1, 0.09:1, 0.1:1 or 0.11:1, but not limited thereto. If the ratio is too small, the lamp bead will not be able to prevent collision after being attached to the screen; if the ratio is too large, the distance between different functional pins 121 will be too small, which may cause signal interference and other problems, affecting the normal operation of the circuit and the performance of the LED device.

[0056] The encapsulation layer 3 covers the LED chip 21 and the substrate 1. In a preferred embodiment, the side of the encapsulation layer 3 above each LED chip 21 facing away from the substrate 1 is convex. More preferably, the encapsulation layer 3 above each LED chip 21 is spherical, which improves the brightness of different LED chips 21 at the same level, and the light-emitting angle of the LED chip 21 is not affected by the position, thereby improving the overall brightness of the lamp bead and the overall performance of the LED device.

[0057] Specifically, the bonding region 111 includes a first bonding region 111a, a second bonding region 111b and a third bonding region 111c, and the bonding wire region 112 includes a first bonding wire region 112a, a second bonding wire region 112b, a third bonding wire region 112c, a fourth bonding wire region 112d and a fifth bonding wire region 112e.

[0058] The first solid crystal region 111a, the second solid crystal region 111b and the third solid crystal region 111c are arranged in a straight line, so that the LED chip 21 is centered and symmetrically placed during solid crystal bonding, avoiding asymmetric light-emitting angles caused by the height of the LED chip 21. The first wire bonding region 112a, the second wire bonding region 112b, the third wire bonding region 112c, the fourth wire bonding region 112d and the fifth wire bonding region 112e are arranged clockwise around the solid crystal region 111, and the first wire bonding region 112a and the second wire bonding region 112b are arranged on one side of the solid crystal region 111, and the third wire bonding region 112c, the fourth wire bonding region 112d and the fifth wire bonding region 112e are arranged on the other side of the solid crystal region 111. Reasonably distributed solid crystal regions 111 and wire bonding regions 112 can increase the spacing between the LED chips 21, thereby improving the bonding strength between the encapsulation adhesive layer 3 and the substrate 1.

[0059] The LED chip 21 includes a first chip 21a, a second chip 21b and a third chip 21c. The first chip 21a is fixed on the first solid crystal region 111a and is electrically connected to the first solid crystal region 111a and the fifth welding region 112e, respectively; the second chip 21b is fixed on the second solid crystal region 111b and is electrically connected to the first wire bonding region 112a and the fourth wire bonding region 112d, respectively; and the third chip 21c is fixed on the third solid crystal region 111c and is electrically connected to the second wire bonding region 112b and the third wire bonding region 112c, respectively.

[0060] In one embodiment, the first chip 21a is a red light vertical chip, the second chip 21b is a green light vertical chip, and the third chip 21c is a blue light vertical chip.

[0061] The back circuit 12 includes a first function pin 121a, a second function pin 121b, a third function pin 121c and a fourth function pin 121d. The first bonding wire area 112a is electrically connected to the first function pin 121a through the lead 113, the second bonding wire area 112b is electrically connected to the second function pin second bonding wire area 112b through the lead 113, the third bonding wire area 112c, the fourth bonding wire area 112d and the fifth bonding wire area 112e are connected to each other through the lead 113, and the third bonding wire area 112c is electrically connected to the third function pin 121c through the lead 113, and the first die-bonding area 111a is electrically connected to the fourth function pin 121d through the lead 113.

[0062] Correspondingly, the present invention also discloses a CHIP LED packaging method for obtaining the above-mentioned CHIP LED packaging structure, comprising the following steps:

[0063] S1 , a front circuit 11 is arranged on the front side of a substrate 1 , and a back circuit 12 is arranged on the back side of the substrate 1 . The front circuit 11 includes a plurality of die-bonding regions 111 and wire-bonding regions 112 .

[0064] S2 . Fill the through hole 14 of the substrate 1 with conductive metal so that the front circuit 11 and the back circuit 12 are electrically connected.

[0065] S3 , forming a first ink layer 13 between adjacent crystal-bonding regions 11 .

[0066] In a preferred embodiment, a second ink layer 15 is disposed around the front edge of the substrate 1. The first ink layer 13 and the second ink layer 15 can be obtained by inkjet printing, that is, black liquid ink is formed on the substrate 1 by inkjet printing to form a desired ink layer pattern, and then heated and cured.

[0067] S4 , fixing the LED chip 21 on the die-bonding area 111 , and electrically connecting the LED chip 21 to the wire bonding area 112 .

[0068] S5 , providing a packaging adhesive layer 3 on the LED chip 21 .

[0069] In a preferred embodiment, the encapsulation adhesive layer 3 disposed on each LED chip 21 is molded to form a protrusion through a molding process.

[0070] The present invention will be further described below with specific embodiments:

[0071] Example 1

[0072] This embodiment provides a CHIP LED packaging structure, including a substrate, an LED light-emitting unit and a packaging adhesive layer.

[0073] The front side of the substrate is provided with a front circuit, the back side of the substrate is provided with a back circuit, the substrate is provided with a through hole penetrating the front side and the back side of the substrate, and the front circuit and the back circuit are electrically connected through the through hole; the front circuit includes a plurality of solid crystal regions and welding wire regions, the plurality of solid crystal regions are arranged at intervals, and a first ink layer is provided between adjacent solid crystal regions. The minimum distance between the edge of the first ink layer and the edge of the solid crystal region is 60 μm, the thickness of the first ink layer is 30 μm, and the viscosity of the ink composition forming the first ink layer at 25° C. is 16 mPa·s.

[0074] The crystal bonding area includes a first crystal bonding area, a second crystal bonding area and a third crystal bonding area, and the wire bonding area includes a first wire bonding area, a second wire bonding area, a third wire bonding area, a fourth wire bonding area and a fifth wire bonding area. The first crystal bonding area, the second crystal bonding area and the third crystal bonding area are arranged in a straight line, and the first wire bonding area, the second wire bonding area, the third wire bonding area, the fourth wire bonding area and the fifth wire bonding area are arranged clockwise around the crystal bonding area, and the first wire bonding area and the second wire bonding area are arranged on one side of the crystal bonding area, and the third wire bonding area, the fourth wire bonding area and the fifth wire bonding area are arranged on the other side of the crystal bonding area.

[0075] The back circuit includes a first functional pin, a second functional pin, a third functional pin and a fourth functional pin. The first welding wire area is electrically connected to the first functional pin through a lead, the second welding area is electrically connected to the second functional pin through a lead, the third welding wire area, the fourth welding wire area and the fifth welding wire area are mutually connected through a lead, and the third welding area is electrically connected to the third functional pin through a lead, and the first die-bonding area is electrically connected to the fourth functional pin through a lead. The area ratio of the first functional pin, the second functional pin, the third functional pin and the fourth functional pin to the back of the substrate is 0.08:1.

[0076] The sidewall of the through hole is perpendicular to the back surface of the substrate.

[0077] The LED light-emitting unit includes a first chip, a second chip and a third chip, wherein the first chip is a red light vertical chip, the second chip is a green light upright chip, and the third chip is a blue light upright chip. The first chip is fixed to the first die-bonding area and is electrically connected to the first die-bonding area and the fifth welding area, respectively, the second chip is fixed to the second die-bonding area and is electrically connected to the first wire bonding area and the fourth wire bonding area, respectively, and the third chip is fixed to the third die-bonding area and is electrically connected to the second wire bonding area and the third wire bonding area, respectively.

[0078] The encapsulation adhesive layer covers the LED chip and the substrate, and the top surface of the encapsulation adhesive layer is a plane arranged parallel to the surface of the chip.

[0079] Example 2

[0080] This embodiment provides a CHIP LED packaging structure, which is different from the first embodiment in that the side wall of the through hole is inclined to the back of the substrate, with an angle of 120°. The rest is the same as the first embodiment.

[0081] Example 3

[0082] This embodiment provides a CHIP LED packaging structure, which differs from the second embodiment in that the packaging adhesive layer above the first chip, the second chip and the third chip is convex in a ball-shaped manner on the side facing away from the substrate. The rest is the same as the second embodiment.

[0083] Example 4

[0084] This embodiment provides a CHIP LED packaging structure, which is different from the embodiment 3 in that the edge of the substrate is an insulating region, and a second ink layer is provided on the insulating region. The minimum distance between the edge of the second ink layer and the edge of the substrate is 100 μm, the thickness of the second ink layer is 30 μm, and the viscosity of the ink composition forming the second ink layer at 25° C. is 16 mPa·s. The rest is the same as the embodiment 3.

[0085] Example 5

[0086] This embodiment provides a CHIP LED packaging structure, which is different from Embodiment 4 in that the viscosity of the ink composition forming the first ink layer and the second ink layer at 25° C. is 10 mPa·s.

[0087] Compared with the lamp beads of the existing CHIP LED packaging structure, the CHIP LED packaging structure provided by the embodiment of the present invention has a brightness improvement of 1.8% to 3%. In addition, the aging test was carried out under the conditions of temperature 85°C, humidity 85%, and current 10mA. After aging tests for 336h, 500h, and 1000h, the number of failed lamp beads was 0, which increased the light-emitting angle while improving the reliability of the lamp beads.

[0088] The above is a preferred embodiment of the invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the invention. These improvements and modifications are also considered to be within the scope of protection of the invention.

Claims

1. A CHIP LED packaging structure, characterized in that: It includes a substrate, an LED light-emitting unit and a packaging adhesive layer; The front side of the substrate is provided with a front circuit, the back side of the substrate is provided with a back circuit, the substrate is provided with a through hole penetrating the front side and the back side of the substrate, the front circuit and the back circuit are electrically connected through the through hole; the front circuit includes a plurality of die-bonding areas and wire bonding areas, the plurality of die-bonding areas are arranged at intervals, and a first ink layer is provided between adjacent die-bonding areas; The LED light-emitting unit includes a plurality of LED chips, and the LED chips are fixed on the die-bonding area and are electrically connected to the wire-bonding area; The packaging adhesive layer at least covers the LED chip.

2. The CHIP LED packaging structure according to claim 1, characterized in that: The opening area of ​​the upper surface of the through hole is smaller than the opening area of ​​the lower surface; Conductive metal is arranged in the through hole, and the conductive metal is electrically connected to the front circuit and the back circuit respectively.

3. The CHIP LED packaging structure according to claim 2, characterized in that: A preset angle is formed between the side wall of the through hole and the back surface of the substrate, and the preset angle is 105° to 135°; The cross section of the substrate is rectangular, and the through holes are arranged on the four corners of the substrate.

4. The CHIP LED packaging structure according to claim 1, wherein: The edge of the front side of the substrate is an isolation area, and a second ink layer is provided on the isolation area; The minimum distance between the edge of the second ink layer and the edge of the substrate is 50 μm to 250 μm; and / or, The thickness of the second ink layer is 10 μm to 50 μm; and / or, The minimum distance between the edge of the first ink layer and the edge of the crystal-bonding area is 30 μm to 180 μm; and / or, The thickness of the first ink layer is 10 μm to 50 μm.

5. The CHIP LED packaging structure according to claim 1, wherein: The back circuit includes a plurality of functional pins, and the ratio of the area of ​​each functional pin to the area of ​​the back side of the substrate is (0.04-0.12):

1.

6. The CHIP LED package structure according to claim 1, wherein: The encapsulation glue layer covers the LED chip and the substrate; The side of the packaging glue layer above each LED chip facing away from the substrate is convex.

7. The CHIP LED package structure according to claim 1, wherein: The crystal bonding area includes a first crystal bonding area, a second crystal bonding area and a third crystal bonding area, and the wire bonding area includes a first wire bonding area, a second wire bonding area, a third wire bonding area, a fourth wire bonding area and a fifth wire bonding area; The first solid crystal region, the second solid crystal region and the third solid crystal region are arranged in a straight line; the first welding wire region, the second welding wire region, the third welding wire region, the fourth welding wire region and the fifth welding wire region are arranged clockwise around the solid crystal region, and the first welding wire region and the second welding wire region are arranged on one side of the solid crystal region, and the third welding wire region, the fourth welding wire region and the fifth welding wire region are arranged on the other side of the solid crystal region.

8. The CHIP LED package structure according to claim 7, wherein: The LED chip includes a first chip, a second chip and a third chip; The first chip is fixed on the first die-bonding area and is electrically connected to the first die-bonding area and the fifth welding area, respectively; the second chip is fixed on the second die-bonding area and is electrically connected to the first wire bonding area and the fourth wire bonding area, respectively; and the third chip is fixed on the third die-bonding area and is electrically connected to the second wire bonding area and the third wire bonding area, respectively.

9. The CHIP LED package structure according to claim 7, wherein: The back side circuit includes a first function pin, a second function pin, a third function pin and a fourth function pin; The first welding wire area is electrically connected to the first functional pin through a lead, the second welding wire area is electrically connected to the second functional pin through a lead, the third welding wire area, the fourth welding wire area and the fifth welding wire area are interconnected through leads, and the third welding area is electrically connected to the third functional pin through a lead, and the first die-bonding area is electrically connected to the fourth functional pin through a lead.

10. A CHIP LED packaging method, for obtaining the CHIP LED packaging structure according to any one of claims 1 to 9, characterized in that: The following steps are involved: A front circuit is arranged on the front side of the substrate, and a back circuit is arranged on the back side of the substrate; wherein the front circuit includes a plurality of die-bonding areas and wire-bonding areas; Filling the through hole of the substrate with conductive metal so that the front circuit and the back circuit are electrically connected; Forming a first ink layer between adjacent solid crystal regions; Printing an ink composition on the substrate between adjacent solid crystal regions to form a first ink layer, wherein the viscosity of the ink composition at 25° C. is 5 mPa·s to 15 mPa·s; and / or the surface tension of the ink composition is 25 mN / m to 55 mN / m; Fixing the LED chip on the die-bonding area, and electrically connecting the LED chip to the wire-bonding area; A packaging glue layer is provided on the LED chip.

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