A packaging structure and packaging process of a surface-mount light-emitting diode

Abstract

The present invention discloses a packaging structure and packaging process of a surface-mount light-emitting diode, and relates to the field of LED packaging. The packaging structure includes a PCB circuit board, the PCB circuit board includes a PCB substrate, a conductive layer covering the surface of the PCB substrate, and an insulating paint layer covering the surface of the conductive layer, the surface of the conductive layer has a groove, and the groove is filled with insulating paint. The present invention arranges grooves on the surface of the conductive layer of the PCB circuit board, and applies insulating paint on the surface of the conductive layer and the groove to form an insulating paint layer, which effectively solves the problem in the prior art that solder penetrates into the conductive layer during reflow soldering, resulting in the peeling of the light-transmitting packaging colloid and the PCB circuit board, and at the same time, it can also enhance the bonding force between the insulating paint and the PCB, thereby improving the quality of LED products.

Description

Technical Field

[0001] The invention relates to the field of LED packaging, and in particular to a packaging structure and packaging process of a surface mount type light emitting diode. Background Art

[0002] The existing LED packaging is completed by bonding the circuit on the PCB substrate. Figure 1 As shown, the manufacturing method is as follows: (1) first fix the chip 1-2 on one of the two different electrodes of the PCB circuit board 1-1 with a solid crystal glue; (2) plant a conductive metal ball 1-3 (called the first solder joint) on the chip electrode, and pull the conductive metal wire 1-4 to solder to the other electrode of the PCB circuit board 1-1 (called the second solder joint), and connect the chip electrode with the other electrode of the PCB circuit board 1-1 to form an electric circuit; (3) then seal the PCB circuit board 1-1 with a translucent colloid 1-5. The existing PCB circuit board surface design is to brush insulating paint (such as Figure 1 However, the solder may still penetrate into the die-bonding area and the wire-bonding area during the reflow process, causing the light-transmitting colloid 1-5 to peel off from the PCB circuit board 1-1, resulting in an open circuit at the welding point between the electrode on the PCB circuit board 1-1 and the die-bonding glue, or between the die-bonding glue and the chip 1-2, or between another electrode on the PCB circuit board and the conductive metal wire 1-4, resulting in poor product quality. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent. To this end, one object of the present invention is to provide a packaging structure and packaging process of a surface-mount light-emitting diode, which is conducive to improving the quality of LED products.

[0004] The technical solution adopted by the present invention is:

[0005] In a first aspect, the present invention provides a packaging structure of a surface-mount light-emitting diode, including a PCB circuit board, wherein the PCB circuit board includes a PCB substrate, a conductive layer covering the surface of the PCB substrate, and an insulating paint layer covering the surface of the conductive layer, wherein the surface of the conductive layer has a groove, and the groove is filled with insulating paint.

[0006] Furthermore, the groove is formed by etching or laser engraving.

[0007] Furthermore, the conductive layer includes a crystal-bonding area and a wire-bonding area, a wafer is fixed to the crystal-bonding area, the wafer includes a wafer electrode, and the wafer electrode is connected to the wire-bonding area through a conductive metal wire.

[0008] Furthermore, the package structure of the SMD light emitting diode further includes a conductive metal ball, which is disposed on the chip electrode and connected to the chip electrode, and is connected to the wire bonding area through a conductive metal wire.

[0009] Furthermore, the wafer is fixed to the crystal bonding area by a crystal bonding adhesive.

[0010] Furthermore, the packaging structure of the SMD light emitting diode also includes a packaging colloid, and the packaging colloid is used to package the PCB circuit board, the chip and the conductive metal wire.

[0011] Furthermore, the encapsulating colloid is a light-transmitting colloid.

[0012] In a second aspect, the present invention provides a packaging process for a surface-mount light-emitting diode, comprising the following steps:

[0013] Etching a conductive circuit on a PCB substrate to form a conductive layer;

[0014] Providing grooves on the surface of the conductive layer;

[0015] Insulating paint is applied on the surface of the conductive layer and the groove to form an insulating paint layer.

[0016] Furthermore, the conductive layer includes a die-bonding area and a wire bonding area, and the packaging process of the SMD light-emitting diode further includes the following steps:

[0017] Fixing a wafer in the crystal-fixing area, wherein the wafer includes a wafer electrode;

[0018] The wafer electrodes are connected to the wire bonding areas through conductive metal wires.

[0019] Furthermore, the packaging process of the surface-mount light-emitting diode further comprises the steps of:

[0020] The PCB circuit board, the chip and the conductive metal wire are packaged by using a packaging colloid.

[0021] The beneficial effects of the present invention are:

[0022] The present invention forms an insulating paint layer by arranging grooves on the surface of the conductive layer of the PCB circuit board and applying insulating paint on the surface of the conductive layer and the grooves, thereby effectively solving the problem in the prior art that the solder penetrates into the conductive layer during reflow soldering, resulting in the peeling of the light-transmitting packaging colloid and the PCB circuit board. At the same time, the bonding force between the insulating paint and the PCB can be enhanced, thereby improving the quality of LED products. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the process of LED packaging process in the prior art;

[0024] Figure 2 It is a structural schematic diagram of an embodiment of a package structure of a surface-mount light-emitting diode in the present invention;

[0025] Figure 3 It is a schematic diagram of a process flow of an embodiment of a packaging process of a surface-mount light-emitting diode in the present invention. DETAILED DESCRIPTION

[0026] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0027] Embodiment 1

[0028] This embodiment provides a packaging structure of a surface mount light emitting diode, such as Figure 2 As shown, the packaging structure includes a PCB circuit board 1. The PCB circuit board 1 includes a PCB substrate 11, a conductive layer 12 covering the surface of the PCB substrate, and an insulating paint layer 13 covering the surface of the conductive layer. Figure 2 The conductive layer 12 has a groove 121 on its surface, and the groove 121 is filled with insulating paint.

[0029] In this embodiment, the groove 121 is formed by etching or laser engraving.

[0030] Reference Figure 2 In this embodiment, the conductive layer 12 includes a solid crystal region 122 and a wire bonding region 123. A wafer 124 is fixed to the solid crystal region 122. The wafer 124 includes a wafer electrode 125. The wafer electrode 125 is connected to the wire bonding region 123 through a conductive metal wire 126 to form an electrical circuit.

[0031] Preferably, a conductive metal ball 127 is also provided on the wafer electrode 125. Specifically, the conductive metal ball 127 is connected to the wafer electrode 125 by welding, and then the conductive metal ball 127 is connected to the wire bonding area 123 through the conductive metal wire 126. Planting the conductive metal ball 127 on the wafer electrode 125 can increase the bonding force between the wafer electrode 125 and the conductive metal wire 126, so that the conductive metal wire 126 is not easily separated from the wafer electrode 125.

[0032] In this embodiment, the chip 124 is fixed to the die-bonding area 122 by a die-bonding adhesive. It is worth noting that when the chip 124 is a unipolar chip, the die-bonding adhesive should be a conductive adhesive (such as silver adhesive) to play a role of bonding and conduction; when the chip 124 is a bipolar chip, the die-bonding adhesive should be an insulating adhesive to play a role of bonding and fixing.

[0033] Reference Figure 2In this embodiment, the packaging structure further includes a packaging colloid 2, and the packaging colloid 2 is used to package the above-mentioned PCB circuit board 1, chip 124 and conductive metal wire 126.

[0034] In this embodiment, since the packaging structure is used for SMD LEDs and the chip 124 is a light emitting chip or a light receiving chip, the packaging colloid 2 should be a light-transmitting colloid, such as resin glue or silicone glue, to ensure light transmittance.

[0035] Embodiment 2

[0036] This embodiment provides a packaging process for a surface-mount light-emitting diode. Figure 3 As shown, the following steps are included:

[0037] S1. Etching a conductive line on a PCB substrate to form a conductive layer;

[0038] S2. A groove is provided on the surface of the conductive layer;

[0039] S3. Apply insulating paint on the surface of the conductive layer and the grooves to form an insulating paint layer.

[0040] Combination Figure 2 and Figure 3 , specifically:

[0041] Step S1: etching a conductive circuit on the PCB substrate 11 to form a conductive layer 12;

[0042] Step S2: forming two grooves 121 on the surface of the conductive layer 12 by etching or laser engraving;

[0043] Step S3: Apply insulating paint on the surface of the conductive layer 12 and in the groove 121 to form an insulating paint layer 13 ( Figure 3 middle shaded area).

[0044] As described in the first embodiment, the conductive layer 12 includes a die-bonding region 122 and a wire bonding region 123 .

[0045] As an improvement of the technical solution, the packaging process further includes the steps of:

[0046] S4. The wafer 124 is fixed in the solid crystal region 122, and the wafer 124 includes a wafer electrode 125;

[0047] S5 . Connect the wafer electrode 125 to the wire bonding area 123 via the conductive metal wire 126 .

[0048] Combination Figure 2 and Figure 3 , specifically:

[0049] Step S4. Determine the crystal bonding position in the crystal bonding area 122, drip crystal bonding glue at the crystal bonding position, pick up the chip 124 with tweezers or suck it with a nozzle and place it at the crystal bonding position, heat and bake to solidify the crystal bonding glue, so as to fix the chip 124 in the crystal bonding area 122.

[0050] Preferably, in step S4, a conductive metal ball 127 can also be set on the chip electrode 125. The conductive metal ball 127 is connected to the chip electrode 125 by welding. Planting the conductive metal ball 127 on the chip electrode 125 can increase the bonding force between the chip electrode 125 and the conductive metal wire 126, so that the conductive metal wire 126 is not easily detached from the chip electrode 125.

[0051] Step S5: Connect the chip electrode 125 (or the conductive metal ball 127) to the wire bonding area 123 through the conductive metal wire 126 to form an electrical circuit.

[0052] As an improvement of the technical solution, the packaging process further includes the steps of:

[0053] Step S6: using the packaging colloid 2 to package the PCB circuit board 1, the chip 124 and the conductive metal wire 126.

[0054] In this embodiment, since the packaging process is applied to SMD light emitting diodes, the chip 124 is a light emitting chip or a light receiving chip, so the packaging colloid 2 should be made of a light-transmitting colloid, such as resin glue or silicone glue, to ensure light transmittance.

[0055] In the existing LED packaging process, insulating paint is applied on the conductive circuit (i.e., the conductive layer) to prevent the solder from penetrating into the solid crystal area and the wire bonding area during reflow soldering. However, there is still a situation in which the solder penetrates into the solid crystal area and the wire bonding area during the reflow soldering process, causing the light-transmitting colloid to peel off from the PCB circuit board, resulting in an open circuit at the welding point between the electrode on the PCB circuit board and the solid crystal glue, or the solid crystal glue and the wafer, or another electrode on the PCB circuit board and the conductive metal wire, resulting in poor product quality. The present invention forms a groove on the conductive layer by etching or laser engraving, and applies insulating paint on the surface of the conductive layer in the groove and near the groove to form an insulating paint layer. This method can effectively solve the problem of the light-transmitting packaging colloid peeling off from the PCB circuit board due to the solder penetrating into the solid crystal area and the wire bonding area during reflow soldering. At the same time, due to the increase in the application area of ​​the insulating paint, the bonding force between the insulating paint and the PCB circuit board can be enhanced, thereby improving the quality of LED products.

[0056] The above is a specific description of the preferred implementation of the present invention, but the invention is not limited to the embodiments. Those skilled in the art can make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A packaging structure of a surface-mount light-emitting diode, characterized in that: The PCB circuit board includes a PCB substrate, a conductive layer covering the upper and lower surfaces of the PCB substrate, and an insulating paint layer covering the surface of the conductive layer. The conductive layer is located on the upper surface outside the two ends of the light-emitting diode and has a groove that does not penetrate the conductive layer. The groove is filled with insulating paint. The insulating paint and the insulating paint layer are integrally formed. The groove is used to prevent solder from penetrating into the conductive layer during reflow soldering. The conductive layer includes a crystal-fixing area and a wire-bonding area, a wafer is fixed to the crystal-fixing area, the wafer includes a wafer electrode, and the wafer electrode is connected to the wire-bonding area through a conductive metal wire; The package structure of the SMD light emitting diode further includes a conductive metal ball, which is disposed on the chip electrode and connected to the chip electrode, and is connected to the wire bonding area through a conductive metal wire.

2. The packaging structure of a surface-mount light-emitting diode according to claim 1, characterized in that: The groove is formed by etching or laser engraving.

3. The packaging structure of a surface-mount light-emitting diode according to claim 1, characterized in that: The wafer is fixed to the crystal bonding area by a crystal bonding adhesive.

4. The packaging structure of a surface-mount light-emitting diode according to claim 3, characterized in that: The packaging structure of the SMD light emitting diode also includes a packaging colloid, and the packaging colloid is used to package the PCB circuit board, the chip and the conductive metal wire.

5. The packaging structure of a surface-mount light-emitting diode according to claim 4, characterized in that: The encapsulating colloid is a light-transmitting colloid.

6. A method for manufacturing the package structure of the surface-mount light-emitting diode of claim 1, characterized in that: The following steps are involved: Etching a conductive circuit on the PCB substrate to form a conductive layer covering the upper and lower surfaces of the PCB substrate; A groove that does not penetrate the conductive layer is provided on the upper surface of the conductive layer outside the two ends of the light-emitting diode; Insulating paint is applied on the surface of the conductive layer and the groove to form an insulating paint layer, wherein the insulating paint and the insulating paint layer are integrally formed; the groove is used to prevent solder from penetrating into the conductive layer during reflow soldering; Wherein, the conductive layer includes a solid crystal area and a wire bonding area, and the method for packaging the surface-mount light-emitting diode structure further includes the steps of: Fixing a wafer in the crystal-fixing area, wherein the wafer includes a wafer electrode; The wafer electrodes are connected to the wire bonding areas through conductive metal wires.

7. The method according to claim 6, characterized in that Also includes: The PCB circuit board, the chip and the conductive metal wire are packaged by using packaging colloid.

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