SMD type LED support structure
By using the combination of a meltable support block and a positioning hole in the SMD LED bracket, the problem of inaccurate positioning of the LED chip is solved, high-precision chip packaging is achieved, and the packaging yield is improved.
Patent Information
- Application Number
- CN202422179837.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-05
- Publication Date
- 2025-07-08
- Estimated Expiration
- 2034-09-05
AI Technical Summary
In the prior art, the positioning accuracy of the LED chip in the SMD type bracket bowl cup is insufficient, resulting in a low packaging yield.
The meltable support block and the positioning hole are used to melt the meltable support block and fix the LED chip by heating to achieve accurate positioning and stable bonding.
Improves the packaging accuracy and packaging yield of the LED chip to ensure the correct position of the chip in the bracket.
Smart Images
Figure CN223080440U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of LED brackets, and more specifically, to a structure of an SMD type LED bracket. Background Art
[0002] An LED bracket is one of the most important raw materials for LEDs, responsible for conducting electricity and dissipating heat in the LED packaging structure. The conductive function is mainly achieved by connecting the gold wire to the electrodes of the LED chip. LED brackets include Lamp type LED brackets, SMD (Surface Mounted Device) type brackets, piranha type brackets, high-power brackets, flat type brackets, COB brackets, etc.
[0003] Among them, when packaging an LED chip with an SMD type LED bracket, one or more LED chips are bonded to the bottom of the bracket cup, and finally, liquid epoxy resin is filled in the bracket cup.
[0004] However, due to the small size of the LED chip, it is difficult to accurately place the LED chip at the designated position at the bottom of the bracket cup when fixing the LED chip to the bottom of the bracket cup. Generally, silver glue or insulating glue is used for bonding. Since the glue is in a liquid state during bonding, it is easy for the LED chip to deviate from the aforementioned designated position, affecting the placement accuracy and reducing the packaging yield. Summary of the Utility Model
[0005] The utility model aims to solve at least one of the technical problems existing in the prior art. For this purpose, the utility model provides a structure of an SMD type LED bracket, aiming to improve the accuracy of placing the LED chip in the bracket cup and increase the packaging yield of the LED chip.
[0006] An SMD type LED bracket structure according to an embodiment of the utility model is used for packaging an LED chip. The SMD type LED bracket structure includes a cup body, a fusible support block, and a substrate. The cup body is provided with a concave cavity, and at least one paste area is provided at the bottom of the concave cavity. At least two positioning holes are provided in the paste area, and a fusible support block. One end of the fusible support block is inserted into the positioning hole, and the other end is connected to the bottom of the LED chip. When the fusible support block is heated and melted, the cup body and the LED chip are adhered together, and the cup body is arranged on the substrate.
[0007] According to some embodiments of the utility model, the LED chip is a flip chip. A positive electrode network pad and a negative electrode network pad are provided on the surface of the paste area. The positive electrode network pad and the negative electrode network pad are arranged at an interval from the positioning hole. The number of the positive electrode network pads is equal to the number of the paste areas, and at least one negative electrode network pad is provided.
[0008] According to some embodiments of the present utility model, the LED chip is a flip-chip, and a positive electrode network pad and a negative electrode network pad are provided on the surface of the bottom of the cup body away from the pasting area. The number of the positive electrode network pads is equal to the number of the pasting areas, and at least one negative electrode network pad is provided.
[0009] According to some embodiments of the present utility model, the fusible support block is a solder ball.
[0010] According to some embodiments of the present utility model, a non-network pad is provided on the periphery of the positioning hole.
[0011] According to some embodiments of the present utility model, an anti-adhesive layer is provided on the part of the solder ball not connected to the LED chip.
[0012] According to some embodiments of the present utility model, a first heat dissipation hole is provided on the substrate, and the first heat dissipation hole communicates with the positioning hole.
[0013] According to some embodiments of the present utility model, the first heat dissipation hole has a metallized hole wall.
[0014] According to some embodiments of the present utility model, a heat dissipation pad is provided on the surface of the substrate away from the cup body, and the first heat dissipation hole penetrates through the heat dissipation pad.
[0015] According to some embodiments of the present utility model, second heat dissipation holes insulated from the first heat dissipation hole are arranged in an array on the substrate. The second heat dissipation holes penetrate through the heat dissipation pad and the cup body to connect the pasting areas.
[0016] The SMD type LED bracket structure according to the embodiments of the present utility model has at least the following beneficial effects: By providing a fusible support block, when placing the LED chip in the concave cavity of the cup body, through the cooperation of the fusible support block and the positioning hole, accurate positioning of the LED chip and the cup holder can be achieved, avoiding deviation of the installation position of the LED chip. Then, when heating the LED chip to bond the LED chip to the bonding area, the high temperature during heating heats the fusible support block together, causing the fusible support block to melt and be contained in the positioning hole. After cooling, the LED chip is firmly bonded in the concave cavity of the cup body, thereby improving the packaging accuracy and the packaging yield of the LED chip. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 is a schematic structural diagram of an embodiment of the present utility model;
[0018] Figure 2 is Figure 1 the top view of the embodiment in
[0019] Figure 3Schematic diagram of another embodiment of the present utility model;
[0020] Figure 4 is Figure 3 the top view of the embodiment in
[0021] In the figure:
[0022] LED chip 100, cup body 200, concave cavity 210, paste area 211, positioning hole 212, positive electrode network pad 213, negative electrode network pad 214, non-network pad 215, fusible support block 300, substrate 400, first heat dissipation hole 410, heat dissipation pad 420, second heat dissipation hole 430. Specific embodiments
[0023] The embodiments of the present utility model will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present utility model and should not be construed as a limitation to the present utility model.
[0024] In the description of the present utility model, it should be understood that for the orientation description, such as up, down, etc., the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model 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 construed as a limitation to the present utility model.
[0025] In the description of the present utility model, "a plurality of" refers to more than two. If there is a description of the first and the second, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence of the indicated technical features.
[0026] In the description of the present utility model, unless otherwise clearly defined, words such as "set", "installed", "connected", etc. should be understood in a broad sense. Those skilled in the art can reasonably determine the specific meanings of the above words in the present utility model in combination with the specific content of the technical solution.
[0027] Referring to Figures 1 to 4 as shown, the present utility model discloses an SMD type LED bracket structure for encapsulating an LED chip 100. Specifically, the SMD type LED bracket structure includes a cup body 200, a fusible support block 300, and a substrate 400.
[0028] The cup body 200 is provided with a concave cavity 210, and at least one adhesive area 211 is provided at the bottom of the concave cavity 210. When encapsulating the LED chip 100, the bottom of the LED chip 100 is coated with an adhesive, but the corresponding adhesive needs to be selected according to the type of the LED chip 100. Specifically, when the LED chip 100 is a front-mounted chip, since the positive and negative electrodes of the LED chip 100 are both located on the upper side, the electrodes can be led out through gold wires. At this time, a conductive or non-conductive adhesive can be selected, such as silver glue or insulating glue. Moreover, in order to effectively dissipate the heat generated when the LED chip 100 works, the adhesive can be a thermally conductive epoxy glue or a silicone thermally conductive glue with better thermal conductivity; when the LED chip 100 is a flip-chip, since the positive and negative electrodes of the LED chip 100 are both located on the lower side, the electrodes cannot be led out through gold wires at this time, and only a conductive adhesive can be selected, such as silver glue or a filled conductive glue. It should be noted that the number of the adhesive areas 211 is determined according to the number of LED chips 100 to be encapsulated.
[0029] In order to pre-position the LED chip 100, at least two positioning holes 212 are provided in the adhesive area 211. The positions of the two positioning holes 212 can be located on the same straight edge line or can be diagonally arranged, and more than 2 positioning holes 212 can be provided according to actual requirements and factors such as the size of the LED chip 100. Before positioning and assembling the LED chip 100, the upper end of the fusible support block 300 is connected to the bottom of the LED chip 100. Optionally, if the LED chip 100 is a front-mounted chip, the upper end of the fusible support block 300 can be fixed to the bottom of the LED chip 100 by means of adhesion. If the LED chip 100 is a flip-chip, the upper end of the fusible support block 300 can be fixed to the bottom of the LED chip 100 by means of adhesion or soldering. For the lower end of the support block 300, the fusible support block 300 is inserted into the positioning hole 212, and at this time the position of the LED chip 100 is accurately positioned.
[0030] It should be noted that when the number of positioning holes 212 is two, the number of fusible support blocks 300 should be equal to the number of positioning holes 212. When the number of positioning holes 212 exceeds two, the number of fusible support blocks 300 may not be equal to the number of positioning holes 212, but there should be at least two fusible support blocks 300. In addition, the shape of the fusible support block 300 can be square, spherical, hemispherical, or conical. Correspondingly, the shape of the positioning hole 212 needs to match the shape of the fusible support block 300, and at the same time, it is ensured that the fusible support block 300 can be inserted into the positioning hole 212, and the position of the LED chip 100 will not move horizontally in the plane where the bonding area 211 is located after being inserted. Exemplarily, the shapes of the positioning hole 212 and the fusible support block 300 are spherical. At this time, in order to prevent the part of the fusible support block 300 protruding from the positioning hole 212 from being too high and affecting the bonding of other areas at the bottom of the LED chip 100 to the bonding area 211, the positioning hole 212 can be set deeper. For example, the positioning hole 212 can accommodate more than half of the height of the fusible support block 300. However, it should be noted that at this time, the opening of the spherical positioning hole 212 cannot be smaller than the diameter of the spherical fusible support block 300. Specifically, the opening of the positioning hole 212 can be set as a cylinder, and of course, other methods can also be selected.
[0031] Since the bottom of the LED chip 100 is fixed to the bonding area 211 by the coated adhesive, in order to thermally cure the colloid, the adhesive also needs to be heated. At this time, under the heat generated by heating, the fusible support block 300 gradually melts. After the fusible support block 300 completely melts, it flows into the positioning hole 212, so that the height of the LED chip 100 supported by the fusible support block 300 decreases until the bottom of the LED chip 100 completely adheres to the surface of the bonding area 211. After the adhesive and the fusible support block 300 cool and solidify, the LED chip 100 can be firmly bonded to the cup body 200.
[0032] In this embodiment, by providing the fusible support block 300, when placing the LED chip 100 in the concave cavity 210 of the cup body 200, through the cooperation of the fusible support block 300 and the positioning hole 212, accurate positioning of the LED chip 100 and the cup body 200 can be achieved, avoiding deviation of the installation position of the LED chip 100. Then, when heating the LED chip 100 to bond the LED chip 100 to the bonding area 211, the high temperature during heating heats the fusible support block 300 together, causing the fusible support block 300 to melt and be contained in the positioning hole 212. After cooling, the LED chip 100 can be firmly bonded in the concave cavity 210 of the cup body 200, improving the packaging accuracy of the LED chip 100 and thus effectively improving the packaging yield of the LED chip 100.
[0033] In some embodiments of the present utility model, such asFigure 3 , Figure 4 As shown in Figure 4 , the LED chip 100 is a flip chip. The surface of the bonding area 211 is provided with a non-electrically connected positive electrode network pad 213 and a negative electrode network pad 214. The positive and negative electrodes of the LED chip 100 are both located on the surface of its bottom. At this time, the positive and negative electrodes of the LED chip 100 are respectively bonded to the positive electrode network pad 213 and the negative electrode network pad 214 through a conductive adhesive. It can be understood that the bonding agent can also be coated on other areas of the bottom of the LED chip 100 except for the positive and negative electrodes, so as to expand the contact area between the bottom of the LED chip and the bonding area 211 and improve the bonding force. At the same time, in order to avoid short circuit, both the positive electrode network pad 213 and the negative electrode network pad 214 should be set with a gap from the positioning hole 212, and the glue-coated area at the bottom of the LED chip 100 should not cover the areas where the positive electrode network pad 213 and the negative electrode network pad 214 are located. It should be noted that the number of the positive electrode network pads 213 is equal to the number of the bonding areas 211, and at least one negative electrode network pad 214 should be provided. For example, when one negative electrode network pad 214 is provided, the negative electrode network pads 214 on all the bonding areas 211 are electrically connected, so as to realize the common cathode connection of the LED chips 100. When multiple negative electrode network pads 214 are provided, the injection of the negative electrode current of each LED chip 100 can be controlled separately, or the negative electrode network pads 214 can be connected together through a bus to realize the common cathode connection of the LED chips 100.
[0034] In some embodiments of the present invention, as Figure 1 , Figure 2 shown in Figure 2 , the LED chip 100 is a face-up chip. The area outside the bonding area 211 is provided with a non-electrically connected positive electrode network pad 213 and a negative electrode network pad 214. The positive and negative electrodes of the LED chip 100 are both located on the surface of its top. At this time, the positive and negative electrodes of the LED chip 100 are respectively bonded to the positive electrode network pad 213 and the negative electrode network pad 214 through gold wires. It can be understood that in order to avoid short circuit, the glue-coated area at the bottom of the LED chip 100 should not cover the area where the positioning hole 212 is located. It should be noted that the number of the positive electrode network pads 213 is equal to the number of the bonding areas 211, and at least one negative electrode network pad 214 should be provided. For example, when one negative electrode network pad 214 is provided, the negative electrode network pad 214 is a network pad arranged around all the bonding areas 211. When wiring, the negative electrodes of the LED chips 100 are all connected to the negative electrode network pad 214 through gold wires, so as to realize the common cathode connection of the LED chips 100. When multiple negative electrode network pads 214 are provided, the injection of the negative electrode current of each LED chip 100 can be controlled separately, or the negative electrode network pads 214 can be connected together through a bus to realize the common cathode connection of the LED chips 100.
[0035] In some embodiments of the present utility model, as Figure 1 , Figure 3 shown, the fusible support block 300 is a solder ball. Specifically, solder paste can be printed at the corresponding position at the bottom of the LED chip 100 through a micro stencil, and then heated to form a solder ball.
[0036] In some embodiments of the present utility model, as Figure 2 , Figure 4 shown, in order to enable the solder ball to adhere to the positioning hole 212 and the bottom of the LED chip 100 after melting, a non-network pad 215 is provided on the periphery of the positioning hole 212, and the non-network pad 215 is not connected to the positive and negative electrodes of the LED chip 100.
[0037] In some embodiments of the present utility model, in order to prevent the adhesive from adhering to the surface of the fusible support block 300 when the adhesive is applied to the bottom of the LED chip 100, which affects the insertion of the LED chip 100 into the positioning hole 212, an anti-adhesive layer is provided on the part of the solder ball not connected to the LED chip 100. The material of the anti-adhesive layer is selected according to the type of the adhesive. For example, when the adhesive is glue, the anti-adhesive layer can be paraffin or synthetic silica. When the adhesive is solder, the anti-adhesive layer can be solder resist.
[0038] In some embodiments of the present utility model, as Figure 1 , Figure 3 shown, in order to improve the heat dissipation capacity, a first heat dissipation hole 410 is provided on the substrate 400, and the first heat dissipation hole 410 is communicated with the positioning hole 212.
[0039] In some embodiments of the present utility model, in order to further improve the heat dissipation capacity, the first heat dissipation hole 410 has a metallized hole wall. The metallized hole wall is to deposit a layer of conductive metal, such as copper, on the inner wall of the first heat dissipation hole 410, and specifically, it can be deposited by chemical method or electroplating method.
[0040] In some embodiments of the present utility model, as Figure 1 , Figure 3 shown, in order to further improve the heat dissipation capacity, a heat dissipation pad 420 is provided on the side of the substrate 400 away from the cup body 200, and the first heat dissipation hole 410 penetrates through the heat dissipation pad 420, so that the heat conducted through the first heat dissipation hole 410 can be quickly dissipated through the heat dissipation pad 420.
[0041] In some embodiments of the present utility model, as Figures 1 to 4As shown in the figure, in order to further improve the heat dissipation capacity, second heat dissipation holes 430 insulated from the first heat dissipation holes 410 are arranged in an array on the substrate 400. The second heat dissipation holes 430 penetrate through the heat dissipation pads 420 and the cup body 200. At this time, the second heat dissipation holes 430 are distributed on the surface of the bonding area 211. In this way, the heat generated by the LED chip 100 can also be conducted to the heat dissipation pads 420 through the second heat dissipation holes 430 and finally quickly dissipated through the heat dissipation pads 420. It should be noted that, in order to prevent short circuits here, the second heat dissipation holes 430 are not provided with metallized hole walls, and the aperture of the second heat dissipation holes 430 is reasonably controlled so that the conductive adhesive does not fill the second heat dissipation holes 430.
[0042] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments, and various changes can be made without departing from the gist of the present invention within the scope of knowledge possessed by those of ordinary skill in the art.
Claims
1. An SMD type LED bracket structure for encapsulating LED chips, characterized in that, The SMD type LED bracket structure includes: A cup body, which is provided with a concave cavity. At least one pasting area is provided at the bottom of the concave cavity, and at least two positioning holes are provided in the pasting area; A fusible support block, one end of which is inserted into the positioning hole, and the other end is connected to the bottom of the LED chip. When the fusible support block is heated and melted, the cup body and the LED chip are adhered together; A substrate, on which the cup body is provided.
2. The SMD type LED bracket structure according to claim 1, characterized in that, The LED chip is a flip chip. A positive electrode network pad and a negative electrode network pad are provided on the surface of the pasting area. The positive electrode network pad and the negative electrode network pad are both arranged at intervals with the positioning holes. The number of the positive electrode network pads is equal to the number of the pasting areas, and at least one negative electrode network pad is provided.
3. The SMD type LED bracket structure according to claim 1, characterized in that, The LED chip is a front-mounted chip. A positive electrode network pad and a negative electrode network pad are provided on the surface of the bottom of the cup body far away from the pasting area. The number of the positive electrode network pads is equal to the number of the pasting areas, and at least one negative electrode network pad is provided.
4. The SMD type LED bracket structure according to any one of claims 1 to 3, characterized in that, The fusible support block is a solder ball.
5. The SMD type LED bracket structure according to claim 4, wherein, An unpatterned pad is provided on the periphery of the positioning hole.
6. The SMD type LED bracket structure according to claim 5, wherein An anti-sticking adhesive layer is provided on the part of the solder ball not connected to the LED chip.
7. The SMD type LED bracket structure according to any one of claims 1 to 3, characterized in that, The substrate is provided with a first heat dissipation hole, and the first heat dissipation hole communicates with the positioning hole.
8. The SMD type LED bracket structure according to claim 7, characterized in that, The first heat dissipation hole has a metallized hole wall.
9. The SMD type LED bracket structure according to claim 8, wherein, A heat dissipation pad is provided on the side of the substrate away from the cup body, and the first heat dissipation hole penetrates through the heat dissipation pad.
10. The SMD type LED bracket structure according to claim 9, characterized in that, Second heat dissipation holes insulated from the first heat dissipation hole are arranged in an array on the substrate. The second heat dissipation holes penetrate through the heat dissipation pad and the cup body to connect the pasting area.