An LED lamp bead structure

Abstract

This application relates to an LED chip structure, comprising: a bracket, an IC chip and a light-emitting chip fixed within the bracket, the bottom surface of the IC chip being attached to the bracket, and the bracket also having a first pad and a second pad fixed within it. The IC chip is electrically connected to the first pad via bonding wires, and the light-emitting chip is electrically connected to the second pad. A recessed area is provided within the bracket, and the IC chip is at least partially housed within the recessed area, such that the height between the two ends of the bonding wire is less than the thickness of the IC chip; or, the top surface of the first pad is higher than the top surface of the second pad, such that the height between the two ends of the bonding wire is less than the thickness of the IC chip. By attaching the bottom surface of the IC chip to the bracket and providing a recessed area within the bracket, or by setting the top surface of the first pad to be higher than the top surface of the second pad, this application can reduce the height difference between the first pad and the surface of the IC chip, thereby reducing the angle between the bonding wire and the first pad, increasing the space available for bonding wires, and reducing the possibility of the bonding wires touching the chip.

Description

Technical Field

[0001] This application relates to the field of LED lighting technology, specifically to an LED lamp bead structure. Background Technology

[0002] Currently, in the LED lighting field, TOP series LED chips, as core components of high-brightness and high-reliability light sources, are widely used in displays, backlights, and general lighting equipment. Traditional TOP series LED chips typically employ a standard bracket structure, where the IC chip (integrated circuit chip) serves as the key functional unit, integrating the driving circuitry to achieve more complex optical control. However, as LED technology develops towards higher power and more multifunctionality, the size and height of the IC chip have significantly increased. Compared to conventional LED chips, its increased height and volume result in a substantial increase in the space it occupies within the bracket structure.

[0003] In related technologies, one type of LED lamp bead has the following structure: multiple independent metal pads are fixed inside a plastic bracket, an IC chip is fixed to the surface of one of the metal pads, and the upper surface of the IC chip needs to be electrically connected to the surfaces of other metal pads via bonding wires. This arrangement results in the height between the upper surface of the IC chip and the surface of the metal pads being equal to the full thickness of the IC chip. This causes a large angle between the bonding wires and the pads after the bonding wires connect from the upper surface of the IC chip to the metal pads, making it easy for the bonding wires to touch the chip. This can lead to reliability risks such as LED lamp bead failure and affect product yield.

[0004] Therefore, it is necessary to design a new LED bead structure to overcome the above problems. Summary of the Invention

[0005] This application provides an LED bead structure that can solve the technical problem in related technologies where bonding wires easily come into contact with the chip, leading to LED failure and other reliability risks.

[0006] In a first aspect, embodiments of this application provide an LED lamp bead structure, comprising: a bracket, wherein an IC chip and a light-emitting chip are fixedly disposed within the bracket, the bottom surface of the IC chip is attached to the bracket, and the bracket is further fixedly disposed with a first pad and a second pad, the IC chip being electrically connected to the first pad via bonding wires, and the light-emitting chip being electrically connected to the second pad; a recessed region is provided within the bracket, and the IC chip is at least partially housed within the recessed region, such that the height between the two ends of the bonding wires is less than the thickness of the IC chip; or, the top surface of the first pad is higher than the top surface of the second pad, such that the height between the two ends of the bonding wires is less than the thickness of the IC chip.

[0007] In conjunction with the first aspect, in one embodiment, when a recessed area is provided within the bracket, the depth of the recessed area is less than or equal to the thickness of the IC chip.

[0008] In conjunction with the first aspect, in one embodiment, the area of ​​the recessed region is larger than the area of ​​the IC chip, and the IC chip is fixed to the recessed region by die-attach adhesive disposed within the recessed region.

[0009] In conjunction with the first aspect, in one embodiment, the bracket has a protrusion sandwiched between the first pad and the IC chip.

[0010] In conjunction with the first aspect, in one embodiment, the bracket has a groove, a portion of which is recessed inward to form the recessed area. Both the groove and the recessed area are filled with encapsulating adhesive, and a portion of the encapsulating adhesive is sandwiched between the protrusion and the IC chip.

[0011] In conjunction with the first aspect, in one embodiment, the second pad has a notch, and one end of the IC chip is inserted into the notch.

[0012] In conjunction with the first aspect, in one embodiment, the bracket is fixed with three light-emitting chips, and the three light-emitting chips emit different colors. The three light-emitting chips are distributed on three different sides of the notch, so that the three light-emitting chips are arranged in a triangle.

[0013] In conjunction with the first aspect, in one embodiment, the bracket is provided with three first pads, the three first pads being distributed on three different sides of the IC chip, and the three first pads and the second pads being distributed around the IC chip.

[0014] In conjunction with the first aspect, in one embodiment, when the top surface of the first pad is higher than the top surface of the second pad, the first pad is bent from the bottom of the bracket toward the direction close to the IC chip to form multiple bends.

[0015] In conjunction with the first aspect, in one embodiment, the IC chip is located on the second pad, and an insulating layer is provided between the IC chip and the second pad.

[0016] The beneficial effects of the technical solutions provided in this application include: By attaching the bottom surface of the IC chip to the bracket and setting a recessed area within the bracket, or by setting the top surface of the first pad to be higher than the top surface of the second pad, the height difference between the first pad and the IC chip surface can be reduced, thereby reducing the angle between the bonding wire and the first pad, increasing the space available for bonding wires, and reducing the possibility of bonding wires hitting the chip. This solves the technical problem in related technologies where bonding wires easily hit the chip, leading to reliability risks such as dead LEDs. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the first LED lamp bead structure provided in the embodiments of this application; Figure 2 This is a cross-sectional schematic diagram of the first LED bead structure provided in the embodiments of this application; Figure 3 This is a cross-sectional schematic diagram of a second LED bead structure provided in an embodiment of this application; Figure 4 This is a schematic diagram of the structure of the bracket provided in the embodiments of this application; Figure 5 This is a schematic diagram of the third LED bead structure provided in the embodiments of this application; Figure 6 This is a schematic diagram of the fourth LED bead structure provided in the embodiments of this application; Figure 7 A metal strip punching diagram for the first LED bead structure provided in this application embodiment; Figure 8 This is a punching diagram of a metal strip for a third LED bead structure provided in an embodiment of this application.

[0019] In the picture: 1. Support; 11. Recessed area; 12. Protrusion; 13. Groove; 2. IC chip; 3. Light-emitting chip; 4. First pad; 5. Second pad; 51. Notch; 6. Bonding wire; 7. Die-attach adhesive; 8. Encapsulating adhesive. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0021] This application provides an LED bead structure that can solve the technical problem in related technologies where bonding wires easily come into contact with the chip, causing the LED to fail.

[0022] See Figure 1 The diagram illustrates an LED bead structure provided in this application embodiment. It may include: a support 1, within which an IC chip 2 and a light-emitting chip 3 are fixed. The bottom surface of the IC chip 2 is attached to the support 1. The support 1 also has a first pad 4 and a second pad 5 fixed within it. The IC chip 2 is electrically connected to the first pad 4 via a bonding wire 6, and the light-emitting chip 3 is electrically connected to the second pad 5. A recessed region 11 is provided within the support 1, and the IC chip 2 is at least partially housed within the recessed region 11, such that the height between the two ends of the bonding wire 6 is less than the thickness of the IC chip 2. Alternatively, the top surface of the first pad 4 is higher than the top surface of the second pad 5, such that the height between the two ends of the bonding wire 6 is less than the thickness of the IC chip 2.

[0023] See Figure 1 As shown, in this embodiment, the bracket 1 is preferably made of PPA material, and an IC chip 2 and three light-emitting chips 3 are fixed inside the bracket 1. The three light-emitting chips 3 are, for example, red, green, and blue chips. In one embodiment of the LED bead structure of this embodiment, a recessed area 11 is provided inside the bracket 1 (see...). Figure 2 As shown, the IC chip 2 is placed in the recessed area 11 to reduce the height of the IC chip 2 and decrease the height difference between the IC chip 2 and the first pad 4. In another embodiment, the top surface of the first pad 4 is raised to reduce the height difference between the IC chip 2 and the first pad 4. When the recessed area 11 is provided in the bracket 1, the entire bottom surface of the IC chip 2 is attached to the inner wall of the recessed area 11; when the top surface of the first pad 4 is raised, the IC chip 2 can be attached to the bracket 1 with its entire bottom surface or only a part of it.

[0024] This embodiment addresses the reliability risks associated with bonding wires in related technologies, such as dead LEDs, by attaching the bottom surface of the IC chip 2 to the support 1 and setting a recessed area 11 within the support 1 or setting the top surface of the first pad 4 to be higher than the top surface of the second pad 5. This reduces the height difference between the first pad 4 and the surface of the IC chip 2, thereby reducing the angle α between the bonding wire 6 and the first pad 4, increasing the space available for bonding wires, and reducing the possibility of the bonding wire 6 touching the chip.

[0025] Based on the above technical solution, in one embodiment, when a recessed region 11 is provided within the bracket 1, the depth of the recessed region 11 is less than or equal to the thickness of the IC chip 2. See also... Figure 4 As shown, in this embodiment, the structure of the large pad for placing the light-emitting chip 3 has been modified. The large pad structure previously used for placing the IC chip 2 has been removed, reducing the area of ​​the large pad. During injection molding of the bracket 1, a recessed structure (i.e., recessed area 11) is formed at the location where the IC chip 2 is placed to accommodate the IC chip 2. This design facilitates the formation of the groove during the manufacturing process, as it can be directly obtained by changing the injection core during the injection molding of the bracket 1, eliminating the need for pad folding compared to an L-shaped pad. Furthermore, modifying the large pad reduces the contact area between the original L-shaped pad and the PPA, increasing the airtightness of the bracket 1, reducing moisture ingress, saving materials, and reducing costs. The height difference h between the surface of the IC chip 2 and the first pad 4 can be 0, or greater than 0 but less than the thickness of the IC chip 2. See [reference needed]. Figure 3 As shown, when the recess depth is equal to the thickness of IC chip 2, the height difference h is 0; see [link / reference]. Figure 2 As shown, when the recess depth is less than the thickness of IC chip 2, the height difference h is greater than 0. When the height difference h is 0, the surface of IC chip 2 is flush with the surface of the first pad 4, resulting in the best wire bonding effect.

[0026] During injection molding, to create the support 1 with the recessed area 11, an additional boss structure can be added to the structure of the injection-molded core to form the recessed area 11. During the generation of the first pad 4 and the second pad 5, the metal strip can be punched according to... Figure 7 The punching process shown in the figure leaves space for placing IC chip 2. The blank part in the figure is the remaining metal pad, and the shaded part is the cut-off part.

[0027] Furthermore, in one embodiment, the area of ​​the recessed region 11 is larger than the area of ​​the IC chip 2, and the IC chip 2 is fixed within the recessed region 11 by die-attach adhesive 7 disposed within the recessed region 11. See also Figure 2As shown, in this embodiment, the space of the recessed area 11 is slightly larger than that of the IC chip 2, so that after the IC chip 2 is placed in the recessed area 11, there is still a gap between the IC chip 2 and the inner wall of the recessed area 11. During die bonding, the IC chip 2 is fixed by the die bond adhesive 7 contained in the recessed area 11. This arrangement can firmly fix the IC chip 2 on the bottom surface of the IC chip 2.

[0028] In some alternative embodiments, see Figure 2 As shown, the bracket 1 has a protrusion 12, which is sandwiched between the first pad 4 and the IC chip 2. In this embodiment, the protrusion 12 provided in the bracket 1 can separate the first pad 4 from the IC chip 2, reduce the contact between the first pad 4 and the IC chip 2, and reduce interference.

[0029] Preferred, see Figure 2 As shown, the bracket 1 has a groove 13, and a portion of the groove 13 is recessed inward to form the recessed area 11. Both the groove 13 and the recessed area 11 are filled with encapsulating adhesive 8, and a portion of the encapsulating adhesive 8 is sandwiched between the protrusion 12 and the IC chip 2. In this embodiment, a portion of the groove 13 is recessed downward to form the recessed area 11, and the groove 13 and the recessed area 11 are connected. During encapsulation, both the recessed area 11 and the groove 13 are filled with encapsulating adhesive 8. The encapsulating adhesive 8 enters between the protrusion 12 and the IC chip 2, which can increase the contact area between the encapsulating adhesive 8 and the bracket 1 and improve the airtightness of the bracket 1.

[0030] Furthermore, in one embodiment, the second pad 5 has a notch 51, and one end of the IC chip 2 is inserted into the notch 51. See also Figure 5 As shown, in this embodiment, based on the recessed area 11 on the bracket 1, a concave notch 51 is provided on the second pad 5. One end of the IC chip 2 is inserted into the concave notch 51, so that the second pad 5 surrounds one end of the IC chip 2.

[0031] When the first pad 4 and the second pad 5 are generated, the metal strip can be punched according to... Figure 8 The punching process shown in the figure leaves space for placing IC chip 2. The blank part in the figure is the remaining metal pad, and the shaded part is the cut-off part.

[0032] Based on the above technical solution, in one embodiment, see [reference needed]. Figure 5As shown, the bracket 1 is fixed with three light-emitting chips 3, and the three light-emitting chips 3 emit different colors. The three light-emitting chips 3 are distributed on three different sides of the notch 51, so that the three light-emitting chips 3 are arranged in a triangle. In this embodiment, since one end of the IC chip 2 is inserted into the notch 51, there are partial second pads 5 on three sides of the IC chip 2. The three light-emitting chips 3 (red, green, and blue) are fixed to three different sides of the IC chip 2 respectively, changing the original RGB linear arrangement to a triangular arrangement. This can solve the problem of color deviation of the LED beads to a certain extent. At the same time, because the height difference between the IC chip 2 and the RGB light-emitting chips 3 is reduced (in this embodiment, the first pad 4 can be the same height as the second pad 5), the IC chip 2 can avoid blocking the RGB light output, making the chip light mixing more uniform and increasing the light output efficiency of the LED beads.

[0033] Furthermore, in some alternative embodiments, see Figure 5 As shown, the support 1 is provided with three first solder pads 4, which are distributed on three different sides of the IC chip 2, and the three first solder pads 4 and the second solder pads 5 are distributed around the IC chip 2. In this embodiment, the three first solder pads 4 are respectively distributed on the first, second, and third sides of the IC chip 2, and the second solder pads 5 are distributed on the fourth side of the IC chip 2. At the same time, the second solder pads 5 also surround the first and third sides of the IC chip 2. Considering the position of the electrode bonding wires of the IC chip 2, this embodiment adjusts the positions of the first solder pads 4 and the second solder pads 5 so that the position of the electrode bonding wires of the IC chip 2 is closer to the solder pads to be soldered, thereby making the soldered bonding wires 6 shorter.

[0034] In one alternative implementation, see [link to implementation details]. Figure 6 As shown, when the top surface of the first pad 4 is higher than the top surface of the second pad 5, the first pad 4 is bent from the bottom of the bracket 1 towards the IC chip 2 to form multiple bends. To reduce the height difference between the surface of the IC chip 2 and the first pad 4, this embodiment achieves this by raising the first pad 4 by making multiple bends on the first pad 4, so that the first pad 4 is higher than its original position.

[0035] In this embodiment, by raising the first pad 4, the height difference between it and the IC chip 2 is reduced, so that the surface of the IC chip 2 and the second pad 5 are approximately at the same level. This reduces the angle α between the bonding wire 6 and the first pad 4, increases the space for the bonding wire 6 to contact the pad, and prevents the bonding wire from breaking at point D. With the surface of the IC chip 2 and the first pad 4 approximately at the same level, the range of motion of the bonding nozzle is reduced, which can reduce the possibility of the bonding nozzle hitting the cup wall and improve the product yield.

[0036] Further, preferably, the IC chip 2 is located on the second pad 5, and an insulating layer is provided between the IC chip 2 and the second pad 5. See also Figure 6 As shown, in this embodiment, a second pad 5 can be provided below the IC chip 2. An insulating layer is provided between the second pad 5 and the IC chip 2 to avoid short circuits.

[0037] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0038] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0039] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. An LED lamp bead structure, characterized in that, It includes: A bracket (1) is provided with an IC chip (2) and a light-emitting chip (3) fixed inside the bracket (1). The bottom surface of the IC chip (2) is attached to the bracket (1). The bracket (1) is also provided with a first pad (4) and a second pad (5). The IC chip (2) is electrically connected to the first pad (4) through a bonding wire (6). The light-emitting chip (3) is electrically connected to the second pad (5). The bracket (1) has a recessed area (11) and the IC chip (2) is at least partially housed in the recessed area (11), such that the height between the two ends of the bonding wire (6) is less than the thickness of the IC chip (2); or, the top surface of the first pad (4) is higher than the top surface of the second pad (5), such that the height between the two ends of the bonding wire (6) is less than the thickness of the IC chip (2).

2. The LED lamp bead structure as described in claim 1, characterized in that, When a recessed area (11) is provided in the bracket (1), the depth of the recessed area (11) is less than or equal to the thickness of the IC chip (2).

3. The LED lamp bead structure as described in claim 2, characterized in that, The area of ​​the recessed region (11) is larger than the area of ​​the IC chip (2), and the IC chip (2) is fixed in the recessed region (11) by die bond adhesive (7) contained in the recessed region (11).

4. The LED lamp bead structure as described in claim 2, characterized in that, The bracket (1) has a protrusion (12) sandwiched between the first pad (4) and the IC chip (2).

5. The LED lamp bead structure as described in claim 4, characterized in that, The bracket (1) has a groove (13) inside, and a portion of the groove (13) is recessed inward to form the recessed area (11). Both the groove (13) and the recessed area (11) are filled with encapsulating adhesive (8), and a portion of the encapsulating adhesive (8) is sandwiched between the protrusion (12) and the IC chip (2).

6. The LED lamp bead structure as described in claim 1, characterized in that, The second pad (5) has a notch (51), and one end of the IC chip (2) is inserted into the notch (51).

7. The LED lamp bead structure as described in claim 6, characterized in that, The bracket (1) is fixed with three light-emitting chips (3), and the three light-emitting chips (3) emit different colors. The three light-emitting chips (3) are distributed on three different sides of the notch (51), so that the three light-emitting chips (3) are arranged in a triangle.

8. The LED lamp bead structure as described in claim 6, characterized in that, The bracket (1) is provided with three first pads (4), the three first pads (4) are distributed on three different sides of the IC chip (2), and the three first pads (4) and the second pads (5) are distributed around the IC chip (2).

9. The LED lamp bead structure as described in claim 1, characterized in that, When the top surface of the first pad (4) is higher than the top surface of the second pad (5), the first pad (4) bends from the bottom of the bracket (1) toward the IC chip (2) to form multiple bends.

10. The LED lamp bead structure as described in claim 9, characterized in that, The IC chip (2) is located on the second pad (5), and an insulating layer is provided between the IC chip (2) and the second pad (5).

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