CN107833960A - A kind of LED support and its manufacture method with overflow ducts and overflow launder - Google Patents

Abstract

The invention provides an LED bracket with an overflow channel and an overflow groove and a manufacturing method thereof, including a substrate, the front of the substrate is used for placing LED chips, a pad is provided on the back of the substrate, and a pad is provided on the pad. There is an overflow channel, and an overflow tank is arranged on the overflow channel. The LED bracket with overflow channel and overflow groove and its manufacturing method provided by the present invention, by setting the overflow channel on the welding pad, and setting the overflow groove on the overflow channel, when soldering, the excess solder paste flows into the overflow In the groove, the amount of solder paste is guaranteed, and the consistency of the device process, flatness, and height are improved; and the additional overflow channel increases the area of the pad, further improving the heat conduction effect, and the existence of the overflow channel makes The wetting angle exists inside the overflow tank, which has the effect of QFN/DFN structure, and at the same time ensures the spacing requirements for high-density assembly of light sources.

Description

LED bracket with overflow channel and overflow groove and manufacturing method thereof

technical field

The invention relates to the technical field of LED packaging, in particular to an LED bracket with an overflow channel and an overflow groove and a manufacturing method thereof.

Background technique

At present, cutting-type LED products mostly adopt the form of pad embedding (as shown in Figure 1), but the method of pad embedding has the following problems: 1. When soldering, the solder paste is in a molten state. LEDs are prone to displacement, and as shown in Figure 2, when the amount of solder paste is different, the height of the device will be different, which will affect the optical effect; 2. The thermal conductivity of conventional solder paste materials is only one tenth of that of copper materials. affect the thermal conductivity of the device. 3. When the solder paste is in a molten state, the cohesive force is large, and it is easy to produce voids when soldering in a reflow furnace, which affects the electrical conductivity and thermal conductivity of the device. In IC packaging, in order to solve the above problems, as shown in Figure 3 and Figure 4, in the QFN/DFN (Quad or Dual Flat No-leadPackage) structure of integrated circuit device packaging, there may be a solder wetting angle, but in the LED field , especially in small-pitch LED products, when the light source is assembled in high density, there is a requirement for the spacing between the devices, and the existence of the wetting angle will affect the arrangement of the device spacing, so the QFN/DFN structure with a wetting angle is not suitable for small pitch LED products.

Therefore, the prior art still needs to be improved and developed.

Contents of the invention

The object of the present invention is to provide an LED bracket with an overflow channel and an overflow groove and a manufacturing method thereof, aiming at solving the problems of unevenness of components and poor thermal conductivity in the existing LED bracket during soldering.

In order to solve the above problems, the technical solution of the present invention is as follows:

An LED bracket with an overflow channel and an overflow groove, including a substrate, the front of the substrate is used to place LED chips, and a pad is provided on the back of the substrate, and an overflow extending to the edge of the LED bracket is provided on the pad. The overflow channel is provided with an overflow groove.

In the LED bracket with an overflow channel and an overflow groove, the overflow groove is located at the edge of the LED bracket and is a groove with openings on both sides.

In the LED bracket with an overflow channel and an overflow groove, the length of the overflow groove at the edge of the LED bracket is less than or equal to the length of the overflow channel at the edge of the LED bracket.

In the LED bracket with an overflow channel and an overflow groove, there are multiple overflow channels.

In the LED bracket with an overflow channel and an overflow groove, a bowl structure is arranged around the front surface of the substrate.

In the LED bracket with an overflow channel and an overflow groove, a second overflow groove is arranged on the pad.

A method for manufacturing an LED bracket with an overflow channel and an overflow groove, comprising the following steps:

Step 1: Etching and electroplating the copper substrate to form a plurality of LED bracket basic frames arranged in an array, and adjacent LED bracket basic frames are connected through overflow channels, and overflow grooves are etched on the overflow channels;

Step 2: Use the upper mold and the lower mold to press and inject, and the lower mold seals the overflow tank during molding to prevent the injection material from flowing into;

Step 3: Cut along the overflow groove to form the LED bracket.

In the manufacturing method of the LED bracket with an overflow channel and an overflow groove, in the step 2, a bowl and cup structure is formed on the front surface of the copper substrate during injection molding.

The manufacturing method of the LED bracket with overflow channels and overflow grooves, wherein, in the step 2, thermosetting resin materials are used for injection molding.

The beneficial effects of the present invention include: the LED bracket with an overflow channel and an overflow groove and the manufacturing method thereof provided by the present invention, by setting the overflow channel on the welding pad, and setting the overflow groove on the overflow channel, during welding, The excess solder paste flows into the overflow tank, which ensures the amount of solder paste, improves the consistency of device process, flatness, and height; and the additional overflow channel increases the area of the pad, further improving the heat conduction effect, The existence of the overflow channel makes the wetting angle exist inside the overflow tank, which has the effect of QFN/DFN structure, and at the same time ensures the spacing requirements for high-density assembly of light sources.

Description of drawings

Figure 1 is a schematic diagram of the back of an ordinary EMC product pad-embedded LED bracket.

Fig. 2 is a structural schematic diagram of an LED whose height is inconsistent due to poor welding.

FIG. 3 is a schematic diagram of the back structure of a QFN package.

FIG. 4 is a schematic diagram of a QFN package structure with a wetting angle.

Fig. 5 is a schematic diagram of the side structure of an LED bracket provided with an overflow channel and an overflow groove provided by the present invention.

Fig. 6 is a schematic diagram of the back structure of an LED bracket provided with an overflow channel and an overflow groove provided by the present invention.

Fig. 7 is a side sectional view of an LED bracket provided with an overflow channel and an overflow groove provided by the present invention.

FIG. 8 is a flow chart of manufacturing an LED bracket with an overflow channel and an overflow groove provided by the present invention.

Explanation of reference signs: 1. Welding pad; 2. Substrate; 201. Copper substrate; 202. Thermosetting resin material; 3. LED bracket; 4. Solder paste; 5. PCB board; 6. PCB board pad; 7. Wetting angle; 8. Overflow channel; 9. Overflow tank.

Detailed ways

In order to make the object, technical solution and advantages of the present invention more clear and definite, the present invention will be further described in detail below with reference to the accompanying drawings and examples.

Referring to Figures 5-7, the present invention provides an LED bracket with an overflow channel and an overflow groove, including a substrate 2, preferably, the substrate 2 is made of a copper substrate 201 molded and injected with a thermosetting resin material 202 , such as EMC (Epoxy Molding Compound), SMC (Sheet Molding Compound) and other materials. The front side of the substrate 2 is used to place LED chips. The LED chips can adopt a front-mount chip structure, a vertical chip structure or a flip-chip structure. The front area of the substrate 2 is adaptively adjusted according to different chip structures. A pad 1 is provided on the back of the substrate 2, and the pad 1 is used for connecting an external circuit. Preferably, the pad 1 is a body structure of the copper substrate 201 . An overflow channel 8 is provided on the pad 1, and the setting of the overflow channel 8 increases the surface area of the pad 1, thereby improving the heat conduction effect. An overflow tank 9 is arranged on the overflow channel 8 . The overflow tank 9 can also be called an overflow cavity, a soldering tank or a storage tank, which is in the shape of a groove, and is used to allow excess solder paste to flow in during soldering, so as to solve the problem of device height caused by uneven solder paste during soldering. Inconsistencies, unevenness, etc.

In practical application, referring to Fig. 6 and Fig. 7, the overflow groove 9 is located at the edge of the LED bracket, and is a groove open on both sides, so that the existence of the overflow groove 9 can also generate the wetting angle 7, because the wetting angle 7 is located at the overflow In the launder 9 , comparing with FIG. 4 , it can be seen that the wetting angle 7 of the present invention will not affect the small-pitch LED products.

Preferably, referring to FIG. 6, the length of the overflow groove 9 at the edge of the LED bracket is less than or equal to the length of the overflow channel 8 at the edge of the LED bracket, that is, the partial area between the overflow channel 8 and the adjacent LED bracket is minimized to avoid affect adjacent LEDs.

The shape of the overflow channel 8 can be rectangular, semicircular, semielliptical or other irregular shapes, and the opening shape of the overflow groove 9 can be rectangular, circular, oval or other irregular shapes.

In actual production, the overflow channel 8 is integrally formed with the pad 1 , which simplifies the production process. It can be considered that the surface area of the pad 1 is increased when the pad 1 is manufactured, and the excess part is the overflow channel 8 .

In actual production, in order to further ensure the flatness and height consistency of the device, the number of overflow channels 8 may be multiple, and the number of overflow grooves 9 may be multiple or multiple, which is not limited in the present invention.

In practical applications, the LED bracket can be a flat bracket or a bowl-cup bracket. Preferably, a bowl structure is provided around the front of the substrate 2 to further strengthen the mechanical strength of the LED bracket while ensuring a unique light-emitting surface.

Preferably, in order to further enhance the effect, in addition to providing the overflow channel 8 , a second overflow groove (not shown in the figure) is also arranged on the pad 1 , which functions similarly to the overflow groove 9 .

Referring to Fig. 8, the present invention also provides a method for manufacturing an LED bracket with an overflow channel and an overflow groove, including the following steps:

Step 1: Etching and electroplating the copper substrate to form a plurality of LED bracket basic frames arranged in an array, and adjacent LED bracket basic frames are connected through overflow channels, and overflow grooves are etched on the overflow channels;

Step 2: Use the upper mold and the lower mold to press and inject, and the lower mold seals the overflow tank during molding to prevent the injection material from flowing into;

Step 3: Cut along the overflow groove to form the LED bracket.

Preferably, silver plating enhances conductivity during electroplating. In actual production, in the step 2, during injection molding, a bowl and cup structure is formed on the front of the copper substrate. In actual production, in the step 2, thermosetting resin materials are used for injection molding. The thermosetting resin material may be EMC (Epoxy Molding Compound), SMC (Sheet Molding Compound) and other materials.

The LED bracket with overflow channel and overflow groove and its manufacturing method provided by the present invention, by setting the overflow channel on the welding pad, and setting the overflow groove on the overflow channel, when soldering, the excess solder paste flows into the overflow In the groove, the amount of solder paste is guaranteed, and the consistency of the device process, flatness, and height are improved; and the additional overflow channel increases the area of the pad, further improving the heat conduction effect, and the existence of the overflow channel makes The wetting angle exists inside the overflow tank, which has the effect of QFN/DFN structure in integrated circuit device packaging, and at the same time ensures the spacing requirements for high-density assembly of light sources.

It should be understood that the application of the present invention is not limited to the above examples, and those skilled in the art can make improvements or transformations according to the above descriptions, and all these improvements and transformations should belong to the protection scope of the appended claims of the present invention.

Claims (9)

1. A LED bracket with an overflow channel and an overflow tank, characterized in that it includes a substrate, the front of the substrate is used to place LED chips, the back of the substrate is provided with a pad, and the pad is provided with an outer The overflow channel extending to the edge of the LED bracket is provided with an overflow groove. 2 . The LED bracket having an overflow channel and an overflow groove according to claim 1 , wherein the overflow groove is located at the edge of the LED bracket and is a groove with openings on both sides. 3. The LED bracket having an overflow channel and an overflow tank according to claim 2, wherein the length of the overflow channel at the edge of the LED bracket is less than or equal to the length of the overflow channel at the edge of the LED bracket . 4 . The LED bracket with overflow channels and overflow grooves according to claim 1 , wherein there are multiple overflow channels. 5. The LED bracket with an overflow channel and an overflow groove according to claim 1, wherein a bowl structure is arranged around the front surface of the substrate. 6 . The LED bracket having an overflow channel and an overflow groove according to claim 1 , wherein a second overflow groove is arranged on the pad. 7. A method for manufacturing an LED bracket with an overflow channel and an overflow tank, comprising the following steps: Step 1: Etching and electroplating the copper substrate to form a plurality of LED bracket basic frames arranged in an array, and adjacent LED bracket basic frames are connected through overflow channels, and overflow grooves are etched on the overflow channels; Step 2: Use the upper mold and the lower mold to press and inject, and the lower mold seals the overflow tank during molding to prevent the injection material from flowing into; Step 3: Cut along the overflow groove to form the LED bracket. 8 . The method for manufacturing an LED bracket having an overflow channel and an overflow groove according to claim 7 , wherein, in the step 2, a bowl and cup structure is formed on the front surface of the copper substrate during injection molding. 9 . The manufacturing method of the LED bracket having an overflow channel and an overflow groove according to claim 7 , wherein in the step 2, thermosetting resin material is used for injection molding. 10 .