LED packaging structure and manufacturing method thereof

Abstract

The invention discloses an LED packaging structure and a manufacturing method thereof, the LED packaging structure comprises a support and an LED wafer, the support comprises a white glue structural member, a first bonding pad and a second bonding pad, the first bonding pad and the second bonding pad are arranged at an interval, the first bonding pad is provided with a first welding area, the second bonding pad is provided with a second welding area, and the white glue structural member comprises a white glue frame and a white glue bottom plate; the periphery of the white glue bottom plate is connected with the white glue frame, the center of the white glue bottom plate is provided with an installation window, the first welding area and the second welding area are arranged corresponding to the installation window, the white glue bottom plate is provided with a plurality of light reflecting protrusions, and the bottom face of the white glue bottom plate is fixedly connected with the first bonding pad and the second bonding pad. The bottom surface of the white rubber frame is fixedly connected with the first bonding pad and the second bonding pad, and the bottom surface of the first bonding pad, the bottom surface of the second bonding pad, the first welding area and the second welding area are respectively provided with an electroplated layer; the LED wafer is arranged corresponding to the window, and the LED wafer is respectively conducted with the first welding area and the second welding area. The LED packaging structure is simple in production process and low in manufacturing cost.

Description

Technical Field

[0001] This invention relates to the field of LED packaging technology, and in particular to an LED packaging structure and its manufacturing method. Background Technology

[0002] As a novel solid-state semiconductor device, LEDs have been widely applied across various industries due to their advantages such as small size, light weight, high luminous efficiency, and energy saving. Currently, many LED companies are optimizing LED packaging structures to improve production efficiency and control costs, with LED flip-chip packaging technology demonstrating a significant competitive advantage.

[0003] like Figure 1 and Figure 2 As shown, the mainstream flip-chip LED packaging structure currently on the market generally adopts a symmetrical cup-shaped structure design. Its bracket manufacturing process often involves first electroplating metal pads 7 to form an electroplated layer 5, followed by applying a white adhesive frame 21. This manufacturing process results in a large electroplating area for the LED packaging structure, leading to higher production costs. Furthermore, when soldering the LED chip 1 using this process, solder paste flux is often required. However, because the electroplating area of ​​the metal pads corresponding to the area inside the white adhesive frame is large, this technology requires an additional flux residue cleaning step after reflow soldering. This necessitates the use of various auxiliary equipment, increasing the complexity of the production process and further pushing up the overall manufacturing cost of semiconductor packages. Moreover, after the flux residue cleaning is completed, a reflective layer 8 is applied around the LED chip using a dispensing process, further complicating the LED packaging structure manufacturing process.

[0004] In addition, the bonding area between the encapsulating adhesive inside the white glue frame and the white glue frame is small, and the interface bonding is unsatisfactory, raising doubts about the long-term reliability of the product. Summary of the Invention

[0005] The technical problem solved by this invention is to provide a low-cost LED packaging structure with a simple production process and its manufacturing method.

[0006] To solve the above-mentioned technical problems, the first technical solution adopted by the present invention is: an LED packaging structure, comprising:

[0007] The bracket includes a white glue structural component and a first solder pad and a second solder pad spaced apart. The first solder pad has a first soldering area, and the second solder pad has a second soldering area. The white glue structural component includes a white glue frame and a white glue base plate. The periphery of the white glue base plate is connected to the white glue frame, and the center of the white glue base plate has an installation window. The first soldering area and the second soldering area are arranged corresponding to the installation window. The white glue base plate has multiple reflective protrusions. The bottom surface of the white glue base plate is fixedly connected to the first solder pad and the second solder pad, respectively. The bottom surface of the white glue frame is fixedly connected to the first solder pad and the second solder pad, respectively. The bottom surface of the first solder pad, the bottom surface of the second solder pad, the first soldering area, and the second soldering area each have an electroplated layer.

[0008] LED chips are arranged corresponding to the window, and the LED chips are respectively welded and connected to the electroplated layers on the first welding area and the second welding area.

[0009] An encapsulating colloid fills the hollow area of ​​the white adhesive frame and covers the LED chip and the white adhesive base plate.

[0010] In one embodiment, the bracket further includes an insulating joint located between the first pad and the second pad, wherein the first pad, the insulating joint, and the second pad are sequentially connected to form an integral structure.

[0011] In one embodiment, the integral structure is plate-shaped.

[0012] In one embodiment, a plurality of the reflective protrusions are arranged in multiple concentric rings around the mounting window, with each ring including a plurality of the reflective protrusions.

[0013] In one embodiment, the surface of the reflective protrusion is spherical.

[0014] In one embodiment, the white glue frame and the white glue base plate are integral injection molded structural components.

[0015] In one embodiment, the white glue structural component, the first solder pad, and the second solder pad are combined into an integral structure by injection molding.

[0016] In one embodiment, the electroplated layer includes an inner layer and an outer layer located on the outer surface of the inner layer.

[0017] In one embodiment, the outer wall surfaces of the first pad and the second pad respectively have the electroplated layer.

[0018] To solve the above-mentioned technical problems, the second technical solution adopted by the present invention is: a method for manufacturing an LED packaging structure, used to manufacture the above-mentioned LED packaging structure, comprising the following steps.

[0019] Obtain the first pad and the second pad;

[0020] The white glue structural component is formed by injection molding on the first and second pads to obtain the intermediate structural component;

[0021] Electroplating is performed on the intermediate structural components;

[0022] Solder LED chips at the mounting window;

[0023] Fill the hollow area of ​​the white glue frame with encapsulating glue.

[0024] The beneficial effects of this invention are as follows: The total electroplating area of ​​this LED packaging structure is small, effectively reducing electroplating costs; after LED chip bonding, flux diffusion is precisely limited within the mounting window, eliminating the need for a flux cleaning process and completely avoiding yellowing and carbonization of surrounding materials caused by flux overflow, thus simplifying the LED packaging structure's production process. Furthermore, the reflective protrusions on the white adhesive structural component optimize the light reflection path, eliminating the need for an additional reflective layer, further simplifying the LED packaging structure's production process and significantly reducing manufacturing costs. In addition, the encapsulating adhesive within the white adhesive frame bonds to both the inner peripheral wall of the frame and the base plate, effectively increasing the bonding area between the white adhesive structural component and the encapsulating adhesive, thereby enhancing the interfacial bonding strength and improving the long-term reliability of the product. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0026] Figure 1 This is a top view of an existing LED packaging structure;

[0027] Figure 2 This is a cross-sectional view of a prior art LED packaging structure;

[0028] Figure 3 This is a top view of the LED packaging structure according to Embodiment 1 of the present invention;

[0029] Figure 4 This is a cross-sectional view of the LED packaging structure according to Embodiment 1 of the present invention.

[0030] Explanation of icon numbers:

[0031] 1. LED chips;

[0032] 2. White glue structural components; 21. White glue frame; 22. White glue base plate; 23. Mounting window; 24. Reflective protrusions;

[0033] 3. First pad;

[0034] 4. Second pad;

[0035] 5. Electroplating layer;

[0036] 6. Insulating joints;

[0037] 7. Metal solder pads;

[0038] 8. Reflective layer. Detailed Implementation

[0039] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings.

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0041] It should be noted that if the embodiments of the present invention involve directional indicators such as up, down, left, right, front, back, etc., the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture as shown in the attached figure. If the specific posture changes, the directional indicators will also change accordingly.

[0042] Furthermore, if the embodiments of the present invention involve descriptions such as "first" or "second," such descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature.

[0043] Furthermore, if the meaning of "and / or" in the entire text is to include three parallel solutions, taking "and A / or B" as an example, it includes solution A, solution B, and a solution that simultaneously satisfies A and B. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0044] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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 of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0045] Example 1

[0046] Please refer to Figure 3 and Figure 4 The first embodiment of the present invention is: an LED packaging structure, including a bracket, an LED chip 1 and a packaging colloid (not shown in the figure). The bracket includes a white glue structure 2 and a first pad 3 and a second pad 4 spaced apart. The first pad 3 has a first welding area, and the second pad 4 has a second welding area. The first welding area and the second welding area are respectively used to bond the positive electrode and the negative electrode of the LED chip 1.

[0047] The white glue structural component 2 includes a white glue frame 21 and a white glue base plate 22. The white glue base plate 22 is located at the bottom of the hollow area of ​​the white glue frame 21. The periphery of the white glue base plate 22 is connected to the white glue frame 21. The white glue frame 21 and the white glue base plate 22 are an integral injection molded structural component. The white glue base plate 22 has an installation window 23 in the center. The first welding area and the second welding area are set corresponding to the installation window 23. The white glue base plate 22 has multiple reflective protrusions 24. The reflective protrusions 24 and the white glue base plate 22 are integrally formed. The bottom surface of the white glue base plate 22 is fixedly connected to the first solder pad 3 and the second solder pad 4 respectively. The bottom surface of the first solder pad 3, the bottom surface of the second solder pad 4, the first welding area and the second welding area are respectively electroplated with an electroplated layer 5.

[0048] The LED chip 1 is positioned corresponding to the window, and the LED chip 1 is welded and connected to the electroplating layer 5 on the first welding area and the electroplating layer 5 on the second welding area, respectively.

[0049] The encapsulating colloid fills the hollow area of ​​the white glue frame 21 and covers the LED chip 1 and the white glue base plate 22.

[0050] The bracket also includes an insulating joint 6, which is located between the first pad 3 and the second pad 4. The first pad 3, the insulating joint 6, and the second pad 4 are connected in sequence to form an integral structure. Preferably, the integral structure is plate-shaped.

[0051] Multiple reflective protrusions 24 are arranged in multiple concentric rings around the mounting window 23, with each ring including multiple reflective protrusions 24; optionally, the surface of the reflective protrusions 24 is spherical. By utilizing the reflective protrusions 24 to optimize the light reflection path, the number of times light is reflected inside the bracket is reduced, and the propagation direction of some light rays is improved, thereby increasing the luminous intensity and light extraction efficiency around the LED beads, and significantly improving the light emission uniformity of the LED beads.

[0052] The white adhesive structural component 2, the first solder pad 3, and the second solder pad 4 are integrated into a single structure via injection molding. In one or more embodiments, the insulating joint 6 is formed simultaneously with the white adhesive structural component 2 during its molding process; that is, the material of the insulating joint 6 is the same as that of the white adhesive structural component 2, and they can be connected or not connected. In another embodiment, the first solder pad 3 and the second solder pad 4 can first form the integrated structure via the insulating joint 6, and then the white adhesive structural component 2 can be injection molded onto the integrated structure.

[0053] The electroplated layer 5 includes an inner layer and an outer layer located on the outer surface of the inner layer. In this embodiment, the inner layer is a nickel layer and the outer layer is a gold layer.

[0054] The outer wall surface of the first pad 3 and the outer wall surface of the second pad 4 are respectively provided with the electroplated layer 5.

[0055] The present invention also provides a manufacturing method for manufacturing the above-mentioned LED packaging structure, comprising the following steps:

[0056] S1. Obtain the first pad and the second pad;

[0057] S2. The white glue structural component is formed by injection molding on the first and second pads to obtain the intermediate structural component;

[0058] S3. Electroplating of intermediate structural components;

[0059] S4. Solder the LED chips at the mounting window;

[0060] S5. Fill the hollow area of ​​the white glue frame with encapsulating glue.

[0061] When performing step S1, the first pad and the second pad can be obtained on the metal heat sink by etching.

[0062] When implementing step S2, first select an injection mold that can manufacture a corresponding size installation window according to the size of the LED chip to be installed, and then use an injection molding equipment to combine the first pad and the second pad, so that the other areas of the metal heat sink except for the corresponding installation window are covered by injection molding material, and reflective protrusions are simultaneously formed on the white glue base plate.

[0063] After implementing step S3, an electroplating layer is formed on the bottom surface of the first pad, the outer wall surface of the first pad, the bottom surface of the second pad, the outer wall surface of the second pad, the first welding area, and the second welding area.

[0064] In summary, this LED packaging structure achieves a dual breakthrough in packaging performance and manufacturing cost by employing a process route of "first injection molding to form a unique internal micro-optical structure, and then electroplating." Structurally, this novel LED packaging structure effectively increases the contact area between the encapsulant and the white adhesive structure through a micro-lens optical structure (i.e., a white adhesive base plate with reflective protrusions), significantly enhancing interfacial adhesion and improving the long-term reliability of the product. Simultaneously, the presence of reflective protrusions optimizes the light reflection path, greatly improving the light emission uniformity of the LED chips. Furthermore, this LED packaging structure effectively reduces the electroplating area, significantly lowering production costs. In terms of process design, the LED packaging structure adopts a customized pre-reserved design for the LED chip size (i.e., an installation window), ensuring that flux diffusion after LED chip bonding is precisely limited to the bottom area of ​​the LED chip, completely avoiding yellowing and carbonization of surrounding materials caused by flux overflow. This design not only eliminates the reflective layer dispensing process in traditional processes but also significantly extends product lifespan by reducing potential failure risks.

[0065] The above are merely optional embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. An LED packaging structure, characterized in that: include The bracket includes a white glue structural component and a first solder pad and a second solder pad spaced apart. The first solder pad has a first soldering area, and the second solder pad has a second soldering area. The white glue structural component includes a white glue frame and a white glue base plate. The periphery of the white glue base plate is connected to the white glue frame, and the center of the white glue base plate has an installation window. The first soldering area and the second soldering area are arranged corresponding to the installation window. The white glue base plate has multiple reflective protrusions. The bottom surface of the white glue base plate is fixedly connected to the first solder pad and the second solder pad, respectively. The bottom surface of the white glue frame is fixedly connected to the first solder pad and the second solder pad, respectively. The bottom surface of the first solder pad, the bottom surface of the second solder pad, the first soldering area, and the second soldering area each have an electroplated layer. LED chips are arranged corresponding to the window, and the LED chips are respectively welded and connected to the electroplated layers on the first welding area and the second welding area. An encapsulating colloid fills the hollow area of ​​the white adhesive frame and covers the LED chip and the white adhesive base plate.

2. The LED packaging structure according to claim 1, characterized in that: The bracket also includes an insulating joint located between the first pad and the second pad. The first pad, the insulating joint, and the second pad are connected in sequence to form an integral structure.

3. The LED packaging structure according to claim 2, characterized in that: The integral structure is plate-shaped.

4. The LED packaging structure according to claim 1, characterized in that: The reflective protrusions, in multiple concentric rings, surround the mounting window, with each ring including multiple reflective protrusions.

5. The LED packaging structure according to claim 1, characterized in that: The reflective protrusion has a spherical surface.

6. The LED packaging structure according to claim 1, characterized in that: The white glue frame and white glue base plate are integral injection molded structural components.

7. The LED packaging structure according to claim 1, characterized in that: The white glue structural component, the first solder pad, and the second solder pad are combined into a single structure through injection molding.

8. The LED packaging structure according to claim 1, characterized in that: The electroplated layer includes an inner layer and an outer layer located on the outer surface of the inner layer.

9. The LED packaging structure according to claim 1, characterized in that: The outer wall surfaces of the first pad and the second pad respectively have the electroplated layer.

10. A method for manufacturing an LED packaging structure, characterized in that: The method for manufacturing the LED packaging structure according to any one of claims 1-9 includes the following steps. Obtain the first pad and the second pad; The white glue structural component is formed by injection molding on the first and second pads to obtain the intermediate structural component; Electroplating is performed on the intermediate structural components; Solder LED chips at the mounting window; Fill the hollow area of ​​the white glue frame with encapsulating glue.

Images