TWI859923B - Light emitting diode package assembly - Google Patents

Abstract

A light emitting diode package assembly is provided. The light emitting diode package assembly includes a circuit board, a reflection member, one or more light emitting diodes and one or more lenses. The reflection member is disposed on the circuit board and has one or more through holes. The one or more light-emitting diodes are arranged on the circuit board and correspond to the one or more through holes, respectively. The one or more lenses are disposed on the reflective member and correspond to the one or more through holes, respectively. An annular trench is located between an upper surface and a side surface of the reflection member, and a light-absorbing material covers the upper surface of the reflective member and fills the annular trench.

Description

LED Package Components

The present invention relates to a packaging component, in particular to a light-emitting diode packaging component.

Semiconductor lighting is widely used in the field of general display. Among them, light-emitting diodes (LEDs) are widely used in outdoor display devices due to their high brightness and high power. In existing LEDs, plastic leaded chip carrier (PLCC) type packaging is often used. However, this type of packaging method has many defects.

Specifically, the PLCC package is a plastic shell that wraps a metal lead frame. During the manufacturing process of the PLCC package, multiple bending processes are required to form the metal lead frame, which is not only time-consuming but also leads to increased costs. Furthermore, the gap between the metal lead frame and the plastic shell is also easy for moisture to enter, making the tolerance of LEDs lower when used in outdoor display devices.

The technical problem to be solved by the present invention is to provide a light-emitting diode packaging component that can improve the durability of the component in view of the shortcomings of the existing technology.

In order to solve the above technical problems, one of the technical solutions adopted by the present invention is to provide a light-emitting diode package assembly, which includes a circuit board, one or more light-emitting diodes and one or more lenses. A reflective component is arranged on the circuit board, and the reflective component has one or more through holes. One or more light-emitting diodes are arranged on the circuit board and correspond to the one or more through holes respectively. One or more lenses are arranged on the reflective component and correspond to the one or more through holes respectively. There is an annular groove between the upper surface and the side surface of the reflective component, and a light-absorbing material covers the upper surface of the reflective component and fills the annular groove.

To further understand the features and technical contents of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings provided are only for reference and description and are not used to limit the present invention.

1: Reflective components

10,41,171: Upper surface

11: Side surface

12: Through hole

121,161:Border wall

14: Groove

140: Annular groove

141: Internal groove

16: Light-absorbing substances

17: Reflective substrate

2: Circuit board

21: Upper surface of circuit board

22: Solder mask

220: Opening of solder mask

23: First metal layer

230: First electrode

231: Second electrode

24: Insulation layer

25: Second metal layer

250: Third electrode

251: Fourth electrode

26: Middle circuit layer

3: LED

32: Conductor wire

4: Filling parts

5: Lens

51: Base

6: LED packaging components

II-II,IX-IX,VII-VII,VIII-VIII: Line segments

R: Resistor element

S10,S11,S12,S13,S14,S15,S101,S102,S103,104: Steps

Figure 1 is a flow chart of a method for manufacturing a light-emitting diode package assembly according to an embodiment of the present invention.

Figure 2A is a schematic diagram of a reflective component of an embodiment of the present invention.

FIG2B is a cross-sectional view drawn along line segment II-II of FIG2A.

Figure 3 is a flow chart of forming a reflective component according to an embodiment of the present invention.

Figure 4 is a schematic diagram of the process of step S101.

Figure 5 is a schematic diagram of the process of step S102.

Figure 6 is a schematic diagram of the process of step S103.

Figure 7A is a schematic diagram of the combination of the reflective component and the circuit board of an embodiment of the present invention.

FIG. 7B is a cross-sectional view drawn along line segment VII-VII of FIG. 7A .

FIG. 7C is another cross-sectional view drawn along line segment VII-VII of FIG. 7A .

FIG8A is a schematic diagram of a light-emitting diode of an embodiment of the present invention disposed on a circuit board.

FIG8B is a cross-sectional view drawn along line segment VIII-VIII of FIG8A.

Figure 9A is a schematic diagram of a lens of an embodiment of the present invention installed on a reflective component.

FIG. 9B is a cross-sectional view drawn along line segment IX-IX of FIG. 9A .

Figure 9C is a cross-sectional view of another embodiment.

FIG. 10A is a first schematic diagram of a light-emitting diode package assembly according to an embodiment of the present invention.

FIG. 10B is a second schematic diagram of the light-emitting diode package assembly of an embodiment of the present invention.

The following is an explanation of the implementation of the "light-emitting diode package assembly" disclosed in the present invention through specific concrete embodiments. Technical personnel in this field can understand the advantages and effects of the present invention from the contents disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and the details in this specification can also be modified and changed in various ways based on different viewpoints and applications without departing from the concept of the present invention. In addition, the drawings of the present invention are only for simple schematic illustrations and are not depicted according to actual sizes. Please note in advance. The following implementation will further explain the relevant technical contents of the present invention in detail, but the disclosed contents are not intended to limit the scope of protection of the present invention. In addition, the term "or" used in this document may include any one or more combinations of the associated listed items as the case may be.

FIG1 is a flow chart of a method for manufacturing a light-emitting diode package assembly according to an embodiment of the present invention. Referring to FIG1 , an embodiment of the present invention provides a method for manufacturing a light-emitting diode package assembly, which includes the following steps:

Step S10: Provide a reflective component. FIG. 2A is a schematic diagram of a reflective component of an embodiment of the present invention, and FIG. 2B is a cross-sectional view drawn along line segment II-II of FIG. 2A. As shown in FIG. 2A and FIG. 2B, the reflective component 1 is, for example, a plate, and includes a plurality of through holes 12 and a plurality of grooves 14 located on the upper surface 10 of the reflective component 1. The light-absorbing material 16 covers the upper surface 10 of the reflective component 1 and completely fills the grooves 14. It should be noted that completely filling means that the light-absorbing material 16 fills the grooves 14 to form a surface above the grooves 14 that is at least flush with the upper surface 10.

In detail, the plurality of grooves 14 may include an annular groove 140 formed between the upper surface 10 and the side surface 11 of the reflective member 1 around one or more through holes 12. In the LED element, the number and configuration of the corresponding through holes 12 may be selected in advance according to the number and configuration of the LEDs to be arranged (for example, arranged in a linear or matrix arrangement), and then the annular groove 140 is formed to surround the selected through holes 12. In some embodiments, the groove 14 further includes an inner groove 141, which may be arranged between two adjacent through holes 12 and connected to the annular groove 140. In some embodiments, some adjacent through holes 12 do not have grooves 14 between them.

It should be noted that the width of the annular groove 140 and the width of the inner groove 141 are both smaller than the width of the through hole 12. From the cross-sectional view, the through hole 12 has a cross section that is wide at the top and narrow at the bottom, so it can be seen that the through hole 12 is a column. In addition, the through hole 12 can have a circular or elliptical vertical projection on the upper surface 10 of the reflective component 1. Therefore, when the vertical projection of the through hole 12 is a circle, the width of the annular groove 140 and the width of the inner groove 141 may be smaller than the diameter of the through hole 12, and when the vertical projection of the through hole 12 is an ellipse, the width of the annular groove 140 and the width of the inner groove 141 may be smaller than the length of the major axis and the length of the minor axis of the through hole 12. Optionally, in terms of depth, the depth of the groove 14 may be between one third and two thirds of the depth of the through hole 12. In other words, the depth of the groove 14 is between one third and two thirds of the thickness of the reflective member 1. Specifically, if the groove 14 is too deep, it will be easy to break along the groove 14 in the subsequent cutting process, and if the groove 14 is too shallow, the black glue coverage on the side of the single LED package component after cutting will be insufficient, affecting the performance of the component. Therefore, it is necessary to strictly control the depth and width of the groove 14, more precisely, it is necessary to strictly control the depth and width of the annular groove 140 and the inner groove 141. In an optional embodiment, the depth of the annular groove 140 is between one sixth and two thirds of the thickness of the reflective member 1, the width of the annular groove 140 is between one third and one half of the depth of the annular groove 140, the depth of the inner groove 141 is between one sixth and two thirds of the thickness of the reflective member 1, and the width of the inner groove 141 is between one third and one half of the depth of the inner groove 141.

The light-absorbing material 16 can be formed, for example, by printing black ink on the upper surface 10, or by using other anti-reflection or matte material processes. When the light-absorbing material 16 is used, it can be ensured that when the LED package assembly is used in an outdoor display device, it will not cause interference when the LED emits light due to strong light reflection.

It should be noted that the reflective component 1 can be pre-fabricated. For example, refer to Figures 3 to 6, Figure 3 is a flow chart of forming the reflective component 1 of the embodiment of the present invention, Figure 4 is a schematic diagram of the process of step S101, Figure 5 is a schematic diagram of the process of step S102, and Figure 6 is a schematic diagram of the process of step S103.

As shown in FIG3 , the reflective member 1 mentioned in the embodiment of the present invention can be preformed by executing the following steps:

Step S101: Provide a reflective substrate, and coat the light-absorbing material on the upper surface of the reflective substrate. As shown in FIG4 , the reflective substrate 17 may be, for example, a substrate including a high reflectivity material, such as a reflective ceramic material (TCM), a metal material such as silver, or a BT resin based on an epoxy resin, to enhance the luminous efficiency, and the light-absorbing material 16 may be, for example, formed on the upper surface 171 by ink printing, or by using other anti-reflective or matte material processes. In this case, from a cross-sectional perspective (as shown in FIG4 ), the side wall 161 of the light-absorbing material 16 and the side wall 121 of the through hole 12 will form a continuous line, which may be a straight line or a curved line. From a structural point of view, the side wall 161 of the light absorbing material 16 and the side wall 121 of the through hole 12 will form a continuous surface, which can be a flat surface or a curved surface.

Step S102: Perform a drilling process on the upper surface of the self-reflective substrate to form a through hole.

As shown in FIG5 , one or more through holes 12 may be formed in the reflective substrate 17. It should be noted that the embodiments of the present invention do not limit the number of through holes, and the number of through holes may be configured as required. For example, a plurality of through holes may be formed linearly or in an array, and then after the array of a plurality of LED packages is completed, they may be cut according to the required number and arrangement. In addition, the side surface of the through hole 12 may be inclined relative to the upper surface 171 to form a columnar through hole 12 that is wide at the top and narrow at the bottom, but the morphology of the through hole 12 is only an example, and the present invention is not limited thereto. In some embodiments, some adjacent through holes 12 do not have a groove 14 between them. It should be noted that since the light-absorbing material is first coated on the reflective substrate 17 and then the reflective substrate 17 is drilled, it is possible to prevent the light-absorbing material 16 from flowing into the through hole 12 and affecting its optical reflection performance.

Step S103: Perform a groove engraving process on the upper surface of the self-reflective substrate to form a groove.

As shown in FIG. 6 , a groove 14 may be formed on the upper surface 171 of the reflective substrate 17. Similar to the above description, the groove 14 may include an annular groove 140 formed around one or more through holes 12. In the LED element, the number and configuration of the corresponding through holes 12 may be selected in advance according to the number and configuration of the LEDs to be arranged, and then the annular groove 140 may be formed to surround the selected through holes 12. In some embodiments, the groove 14 further includes an inner groove 141, which may be arranged between two adjacent through holes 12 and connected to the annular groove 140.

Step S104: Fill the light-absorbing material into the groove. After the light-absorbing material 16 is filled into the groove 14, the reflective component 1 shown in FIG. 2A and FIG. 2B is formed.

Please refer to Figure 1, the manufacturing method of the light-emitting diode package assembly enters step S11: providing a circuit board, combining the reflective component and the circuit board. In this step, the reflective component 1 and the circuit board 2 can be combined by an adhesive such as epoxy resin.

The composition of the circuit board 2 is described below. Please refer to Figures 7A and 7B, Figure 7A is a schematic diagram of the combination of the reflective component and the circuit board of an embodiment of the present invention, and Figure 7B is a cross-sectional view drawn along the line segment VII-VII of Figure 7A. As shown in Figures 7A and 7B, the circuit board 2 has a circuit board upper surface 21. The circuit board 2 may, for example, include a solder mask 22, a first metal layer 23, an insulating layer 24 and a second metal layer 25. The solder mask 22 is disposed on the lower surface of the insulating layer 24 and has a plurality of solder mask openings 220. The first metal layer 23 is disposed on the solder mask 22 and includes a plurality of first electrodes 230 and a plurality of second electrodes 231 exposed by the plurality of solder mask openings 220. The insulating layer 24 is disposed on the first metal layer 23 and may be made of, for example, TCM or resin (e.g., BT resin). The second metal layer 25 is disposed on the insulating layer 24 and includes a plurality of third electrodes 250 and a plurality of fourth electrodes 251 exposed on the upper surface 21 of the circuit board. The first electrode 230 may be electrically connected to the corresponding third electrode 250 through a plurality of through holes in the insulating layer 24, and the second electrode 231 may be electrically connected to the corresponding fourth electrode 251 through a plurality of through holes in the insulating layer 24. The first electrode 230 and the second electrode 231 can form contacts for electrically connecting the light-emitting diode to the outside world, such as positive and negative electrode pads.

It should be noted that the above embodiment only provides one implementation method of the circuit board 2, wherein the LED package assembly may include one or more LEDs 3 driven independently of each other, but the present invention is not limited thereto, and part or all of the multiple LEDs 3 included in the LED package assembly may be driven dependently, for example, part or all of the multiple LEDs 3 may be connected in parallel or in series through the circuit board 2.

On the other hand, please refer to FIG. 7C, which is another cross-sectional view drawn along the line segment VII-VII of FIG. 7A. As shown in FIG. 7C, in another embodiment, the circuit board 2 further includes an intermediate circuit layer 26 disposed between the first metal layer 23 and the second metal layer 25. The intermediate circuit layer 26 may be embedded with a plurality of resistor elements R, each of which is electrically connected to at least one of the first electrodes 230 and its corresponding third electrode 250. Therefore, since the circuit board 2 is added with the phase-embedded resistor element R, the step of setting the resistor element can be omitted in the rear-end assembly.

Step S12: Place the light-emitting diode on the circuit board corresponding to the through hole.

Please refer to FIG. 8A and FIG. 8B. FIG. 8A is a schematic diagram of the LED of the embodiment of the present invention disposed on the circuit board, and FIG. 8B is a cross-sectional view drawn along the line segment VIII-VIII of FIG. 8A. As shown in FIG. 8A and FIG. 8B, the LED 3 can be first disposed at a predetermined position in the through hole 12 by bonding. A plurality of LEDs 3 having one or more colors can be obtained according to requirements, and then the LEDs 3 are disposed in the predetermined through holes 12 according to the predetermined color configuration. Then, the LED 3 is electrically connected to the third electrode 250 (corresponding to the positive and negative electrodes) through the wire 32 by means of wire bonding, so that the basic structure of the LED package can be initially formed.

Step S13: Fill each through hole with a filler. For example, referring to FIG. 8A and FIG. 8B , the filler 4 may be, for example, a light-transmitting material, a light-transmitting material mixed with light-scattering particles, or a light-transmitting material mixed with a color dye, to form a predetermined light shape. The filler 4 is filled in one or more through holes 12. The upper surface 41 of the filler 4 may be at the same height as the upper surface 10 of the reflective member 1, however, the present invention is not limited thereto, and the upper surface 41 of the filler 4 may also be slightly concave toward the bottom of the through hole 12. It should be noted that the filler 4 can be used to fix components such as the light-emitting diode 3, the third electrode 250, and the wire 32, and can also be used as a sealing layer to prevent the above components from directly contacting the outside world and accelerating aging or damage.

Step S14: Install the lens on the reflective component corresponding to the position of the through hole.

Please refer to FIG. 9A and FIG. 9B , FIG. 9A is a schematic diagram of a lens of an embodiment of the present invention installed on a reflective member, and FIG. 9B is a cross-sectional view drawn along the line segment IX-IX of FIG. 9A . As shown in FIG. 9A and FIG. 9B , the lens 5 has a circular or elliptical structure, and its number and position configuration can be arranged on the reflective member 1 corresponding to the number and position configuration of the through holes 12. In addition, the lens 5 can be arranged above the base 51, and the base 51 is directly connected to the upper surface 10 of the reflective member 1. The base 51 can have the same material as the lens 5, and can be integrally formed with the lens 5 to form a lens assembly together with the lens 5. As shown in FIG. 9B , the base 51 can be, for example, a plate, and its side surface 510 is flush with the side surface 11 of the reflective member 1. In some embodiments, the lens 5 and the base 51 may include a transparent material, such as epoxy resin, and may be formed by injection molding. The lens 5 and the base 51 may be used to protect the light-emitting diode 3 and any electrical contacts between the light-emitting diode 3 and the circuit board 2, and may form a predetermined light shape.

In other embodiments, the lens may include light conversion materials (such as phosphors), light scattering particles to mix and package light, and textures to enhance light extraction. The lens may include many different shapes and sizes. In some embodiments, the lens may be dome-shaped, while in other embodiments, the lens 5 may be elliptical to match the shape of the through hole 12, and the lens 5 may also include a mixture of different shapes to enhance the luminous efficiency of the light-emitting diode package assembly. In some embodiments, the base materials of the circuit board 2, the reflective component 1, the light-absorbing substance 16, and the lens 5 may be the same. However, the present invention is not limited to this. In other embodiments, the base materials of the circuit board 2, the reflective component 1, the light-absorbing substance 16, the light-transmitting material forming the filler 4, and the lens 5 may be the same. For example, when a base material mainly made of epoxy resin is used in the package, when the circuit board 2, the reflective component 1, the light-absorbing material 16, the light-transmitting material forming the filler 4 and the lens 5 are combined with each other, the waterproofness of the package can be further enhanced because the homogeneous materials are combined with each other, and the weather resistance and moisture sensitivity level can also be increased.

In addition, since the metal lead frame used in the PLCC packaging method is not used, time and cost can be saved in the manufacturing process, and the gap between the metal lead frame and the plastic shell of the formed LED package can be avoided to cause moisture to enter, further improving the environmental tolerance of the LED package assembly of the present invention when used in outdoor display devices. Furthermore, the LED package assembly of the present invention is not a package substrate that covers the step structure, and can also avoid process defects caused by covering the step difference of the step structure.

It should be further explained that in this embodiment, the lens assembly formed by the lens 5 and the base 51 covers the annular groove 140. However, the present invention is not limited thereto. Please refer to FIG. 9C, which is a cross-sectional view of another embodiment. In the embodiment of FIG. 9C, the lens assembly formed by the lens 5 and the base 51 does not cover the annular groove 140. Under this structure, after the cutting operation described later, the light-absorbing material 16 will be exposed from the side surface 11 and the upper surface 10 of the reflective component 1.

Step S15: Cut along part or all of the grooves.

Please refer to Figures 10A and 10B, Figure 10A is a first schematic diagram of the LED package assembly of the embodiment of the present invention, and Figure 10B is a second schematic diagram of the LED package assembly of the embodiment of the present invention. As shown in Figures 10A and 10B, the finished product after step S14 can be cut according to the position of the groove 14 (for example, the annular groove 140 and/or the internal groove 141) to obtain LED package assemblies 6 of various quantities and configurations. For example, as shown in FIG10A, a single-color and single (1x1) LED package assembly 6 is cut, or a multi-color and multi-piece (1x2, 1x3, 2x2, m*n, m, n are positive integers greater than or equal to 1) matrix-shaped LED package assembly 6 is cut. It should be noted that the arrangement of the LED package assembly 6 is not limited to a single-row straight line form, but can also be a multi-row matrix form. Therefore, it can be cut into a single-color (1x1), three-color RGB (1x3) or four-color RGBY (2x2) LED package assembly 6 according to user needs.

[Beneficial effects of the embodiment]

One of the beneficial effects of the present invention is that, in the LED package assembly and its manufacturing method provided by the present invention, since the metal lead frame adopted by the PLCC packaging method is not used, time and cost can be saved in the manufacturing process, and the gap between the metal lead frame and the plastic shell of the formed LED package can be avoided to cause moisture to enter, further improving the environmental tolerance of the LED package assembly of the present invention when used in outdoor display devices. Furthermore, the LED package assembly and its manufacturing method of the present invention are not through the packaging substrate covering the step structure, and can also avoid the process defects caused by covering the step difference of the step structure.

The above disclosed contents are only the preferred feasible embodiments of the present invention, and do not limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made by using the contents of the specification and drawings of the present invention are included in the scope of the patent application of the present invention.

IX-IX: Line segment

5: Lens

51: Base

Claims (14)

A light-emitting diode package assembly includes: a circuit board; a reflective component disposed on the circuit board, the reflective component having one or more through holes; one or more light-emitting diodes disposed on the circuit board and corresponding to the one or more through holes; and one or more lenses disposed on the reflective component and corresponding to the one or more through holes; wherein an annular groove is provided between the upper surface and the side surface of the reflective component, and a light-absorbing material covers the upper surface of the reflective component and fills the annular groove. The light-emitting diode package assembly as described in claim 1 further includes one or more internal grooves, wherein the one or more internal grooves are arranged between two adjacent through holes and connected to the annular groove, and the internal grooves are filled with the light-absorbing material. The light-emitting diode package assembly as described in claim 1, wherein the depth of the annular groove is between one-third and two-thirds of the thickness of the reflective component, and the width of the annular groove is between one-sixth and one-half of the depth of the annular groove. The light-emitting diode package assembly as described in claim 2, wherein the depth of the internal groove is between one-sixth and two-thirds of the thickness of the reflective component, and the width of the internal groove is between one-third and one-half of the depth of the internal groove. The LED package assembly as described in claim 1 further includes a light-transmitting material filled in the one or more through holes. The LED package assembly as described in claim 1, wherein the one or more lenses have a base, and the side surface of the base is flush with the side surface of the reflective component and the side surface of the reflective component. A light-emitting diode package assembly as described in claim 1, wherein the one or more light-emitting diodes are driven independently of each other. The light-emitting diode package assembly as described in claim 1, wherein a resistor element is embedded in the circuit board. The LED package assembly as described in claim 1, wherein the base materials of the circuit board, the reflective component, the light-absorbing material and the one or more lenses are the same. The LED package assembly as described in claim 5, wherein the base materials of the circuit board, the reflective component, the light-absorbing material, the light-transmitting material and the one or more lenses are the same. The LED package assembly as described in claim 1, wherein the plurality of through holes are arranged linearly or in a matrix. A light-emitting diode package assembly as described in claim 1, wherein the one or more lenses have a circular or elliptical structure. A light-emitting diode package assembly as described in claim 1, wherein the lens assembly formed by the one or more lenses and the base does not cover the annular groove. The LED package assembly as described in claim 1, wherein the side wall of the light-absorbing material and the side wall of the corresponding through hole form a continuous line in a cross-sectional view.

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