KR100638881B1 - Led assembly having led package inserted into metal board - Google Patents

Abstract

An LED in which an LED package is inserted into a metal substrate is provided to easily radiate the heat generated from an LED chip and reduce the size of the LED assembly by inserting the LED package into a metal substrate. A concave part is formed in one surface of a metal substrate(132). An insulation layer(136) is formed on one surface of the metal substrate including the concave part. A circuit pattern(138,140) is formed on the bottom of the insulation layer having the concave part. A substrate part includes the metal substrate, the insulation layer and the circuit pattern. An LED package includes a pair of leads(112,114), an LED chip and a transparent package body. The pair of leads is electrically connected to the circuit pattern, separated from each other. The LED chip is electrically connected to the lead. The leads and the LED chip are encapsulated by the transparent package body. The LED package is inserted into the concave part of the substrate part. The LED package is coupled to the substrate part by a coupling unit. The coupling unit can be solder that couples the circuit pattern to the lead.

Description

LED assembly with LED package in metal substrate {LED ASSEMBLY HAVING LED PACKAGE INSERTED INTO METAL BOARD}

1 is a perspective view showing a cross section of an LED package according to the prior art.

2 is a cross-sectional view illustrating a state in which the LED package of FIG. 1 is mounted.

3 is an exploded perspective view of the LED assembly according to the present invention.

4 is a cross-sectional view of the LED assembly of FIG. 3.

5 is a cross-sectional view of an LED assembly with a plurality of LED packages.

6 is a cross-sectional view of a modification of the LED assembly according to the present invention.

7 is a cross-sectional view showing a step of manufacturing a substrate portion of the LED assembly according to the present invention.

8 is a cross-sectional view showing a step by step LED package manufacturing process of the LED assembly according to the present invention.

Figure 9 is a cross-sectional view showing a step of the LED package assembly and the substrate portion of the LED assembly according to the present invention.

10 is a cross-sectional view showing some steps of a bulk LED package manufacturing process of an LED assembly according to the present invention.

<Explanation of symbols of main parts in drawings>

10, 100: LED assembly, 110: LED package

112 and 114: lead 132: metal substrate

134: recess 136: insulating layer

138 and 140: circuit pattern 150: transparent resin layer

160: diffusion plate

The present invention relates to an LED assembly, and more particularly, by inserting an LED package into a metal substrate to implement the LED assembly, not only can easily remove heat generated from the LED chip, but also simplify the manufacturing process and reduce the size. To provide an LED assembly.

LED (Light Emitting Diode) is a semiconductor device for generating light of various colors when a current is applied, the color of the light generated from the LED is mainly determined by the chemical components constituting the semiconductor chip of the LED. The demand for these LEDs continues to increase as they have several advantages over other light emitting devices, such as long life, low power, good initial drive characteristics, high vibration resistance, and high tolerance for repetitive power interruptions.

Recently, LED is being used as a backlight device for a lighting device and a large liquid crystal display (LCD). Since they require large outputs, these LEDs require a package structure with good heat dissipation.

1 and 2 are views showing a state in which the LED package according to the prior art and the LED package is mounted on a circuit board.

First, referring to FIG. 1, the LED package 10 includes a heat slug 14 serving as a heat guide means while seating the LED chip 12. The LED chip 12 receives electricity from an external power source (not shown) through a pair of wires 16 and a pair of terminals 18 for supplying power. The upper portion of the heat transfer member 14, including the LED chip 12, is sealed with an encapsulant 20, usually made of silicon, which is covered with a lens 22. The housing 24 is formed by ordinary molding around the heat transfer member 14 to support the heat transfer member 14 and the terminal 18.

As shown in FIG. 1, the LED package 10 of FIG. 1 is mounted on a circuit board 30 that is a heat sink to form an LED assembly 40. At this time, a thermal conductive pad 36 such as solder is interposed between the heat transfer member 14 of the LED package 10 and the metal heat dissipation substrate 32 of the circuit board 30 to promote thermal conduction therebetween. In addition, the terminal 18 is also stably connected to the circuit pattern 34 of the circuit board 30 by the solder 38.

However, this LED package has a disadvantage that the structure is complicated. In addition, each part has to be prepared separately and then assembled, resulting in long working hours and high production costs. In addition, in order to use as an LED assembly, as shown in Figure 2 there is a hassle to use a separately produced substrate and attach through soldering or the like. In addition, since the LED assembly is manufactured by attaching the LED to the substrate surface, the LED assembly is enlarged.

Therefore, the present invention has been made to solve the above-described problems of the prior art, an object of the present invention is to insert the LED package on the metal substrate to implement the LED assembly, it is possible to easily remove the heat generated from the LED chip Rather, it provides LED assemblies that can simplify and reduce the manufacturing process.

In order to achieve the above object of the present invention, the present invention provides a substrate having a metal substrate having a recess formed on one surface thereof, an insulating layer provided on one surface of the metal substrate including the recessed portion, and a circuit pattern formed on the bottom of the insulating layer including the recessed portion. part; An LED package inserted into a recess of the substrate part having a pair of leads electrically connected to the circuit pattern and spaced from each other, an LED chip electrically connected to the leads, and a transparent package body encapsulating the leads and the LED chips; ; And a coupling means for coupling the LED package to the substrate.

In the LED assembly of the present invention, the coupling means is characterized in that the solder to couple the circuit pattern and the lead, respectively.

In the LED assembly of the present invention, the coupling means is an adhesive for coupling the LED package to the recess.

The LED assembly of the present invention may further include a diffusion plate attached to one surface of the substrate portion to cover the LED package. In addition, the LED assembly may further include a transparent resin provided between the diffusion plate and the LED package. In this case, the transparent resin preferably contains a fluorescent material for converting short wavelength light into multi-wavelength light.

In the LED assembly of the present invention, the concave portion is plural, and the LED package is characterized in that the same number as the concave portion.

In the LED assembly of the present invention, the lead of the LED package extends from the bottom of the package body to the side wall and the circuit pattern in the recess is characterized in that formed on the inner wall of the recess.

In the LED assembly of the present invention, the coupling means is characterized in that the diffusion plate attached to one surface of the substrate portion to cover the LED package. In addition, the LED assembly may further include a transparent resin provided between the diffusion plate and the LED package. In this case, it is preferable that the transparent resin contains a fluorescent substance for converting short wavelength light into multi wavelength light.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First, referring to FIGS. 3 and 4, FIG. 3 is an exploded perspective view of the LED assembly 100 according to the present invention, and FIG. 4 is a cross-sectional view of the LED assembly 100 of FIG. 3.

The LED assembly 100 includes an LED package 110 in the form of a SMD and a substrate portion 130 having a recess 134 for accommodating the LED package 110.

The LED package 110 includes a pair of leads 112 and 114, an LED chip 116 electrically connected to them, and a transparent package body 120 encapsulating the LED chip 116. The LED chip 116 is seated in the lead 112 and is electrically connected to the leads 112 and 114 by the wire 118. Alternatively, the LED chip 116 may be mounted to the lead 112 in the form of a flip chip by solder bumps. The leads 112 and 114 are made of sheet metal having excellent electrical conductivity and reflectance, and the package body 120 is formed by molding transparent resin. It is preferable that a transparent resin contains a ultraviolet absorber or fluorescent substance which converts short wavelength light into multiple wavelengths.

The substrate portion 130 includes a substrate 132 having a recess 134, an insulating layer 136 provided on the surface of the recess 134 side of the substrate 132 including the recess 134, and the insulating layer. Circuit patterns 138 and 140 provided on a portion of the surface of 136. The substrate 132 is made of a metal such as copper having good thermal conductivity, and the insulating layer 136 is provided to block an electrical connection between the substrate 132 and the circuit patterns 138 and 140. In addition, the recess 134 has the same size as that for accommodating the LED package 110.

Preferably, the leads 112 and 114 may be coupled to the circuit patterns 138 and 140 using solder paste. First, the solder paste is applied to the circuit patterns 138 and 140, and then the LED package 110 is inserted into the recess to bring the leads 112 and 114 into contact with the circuit patterns 138 and 140. In this state, a reflow process is performed to bond the leads 112 and 114 to the circuit patterns 138 and 140 with solder. Typical reflow process is 210 to 260? It is carried out at a temperature for approximately 100 seconds, more preferably at a temperature of 240 to 250 ℃ for about 30 seconds.

On the contrary, before inserting the LED package 110 into the recess 134, an adhesive may be applied to the recess 134 to couple the LED package 110 to the substrate 130. Specifically, when an adhesive is applied to the bottom of the recess 134 except for the circuit patterns 138 and 140, the adhesive strongly bonds the LED package 110 to the recess 134, and the circuit pattern at the bottom of the recess 134. The step by (138, 140) can be eliminated.

When the LED package 110 is coupled to the substrate unit 130 in this manner, the light generated from the LED chip 116 is upward by the lower leads 112 and 114 and the insulating layer 136 in the recess 134. Reflected, heat passes through the leads 112 and the insulating layer 136 to the substrate 132. As such, the LED package 110 may be embedded in the substrate 130 to obtain an effective heat dissipation function. In addition, the mounting height according to the embedding of the LED package 110 can be reduced, thereby reducing the size of the entire LED assembly 100.

In this manner, the diffusion plate 160 may be covered on the LED package 110 in addition to the configuration in which the LED package 110 is inserted into and coupled to the substrate 130. The diffusion plate 160 may be coupled to the above configuration using a transparent adhesive. Alternatively, it may be coupled to the substrate 132 using a variety of fastening means, such as rivets, screws, fastening means is provided on the edge of the substrate 132 so as not to interfere with the light emitted from the LED package 110.

In this case, when the light generated by the LED chip 116 is emitted upward, the light may be uniformly diffused through the diffusion plate 160 to provide uniform illumination.

On the other hand, when the diffusion plate 160 is installed, when the height of the LED package 110 and the height of the substrate recess 134 is the same, the LED package 110 is concave only with the diffusion plate 160 without the above-described solder or adhesive. It can be fixed in the portion 134.

In addition, the transparent resin layer 150 may be provided under the diffusion plate 160. If the transparent resin layer 150 is provided, the diffusion plate 160 can be effectively attached to the coupling configuration of the LED package 110 and the substrate unit 130 without using the above-described adhesive or fastening means. In this case, the transparent resin layer 150 preferably contains a ultraviolet absorber or a fluorescent material for converting short wavelength light into multiple wavelengths.

In this way, even if a short wavelength LED chip is used, there is an advantage that multi-wavelength light can be obtained.

5 is a cross-sectional view of an LED assembly with a plurality of LED packages. That is, the LED assembly 10 of FIG. 5 may include a plurality of LED modules 100A and 100B having the same form as the LED assembly 100 shown in FIGS. 3 and 4. Each of the LED modules 100A and 100B has substantially the same structure as the LED assembly 100 described above, and the circuit pattern 140 connected to the lead 114 of the LED module 100A is connected to the lead of the LED module 100B. 112 and the LED modules 100A and 100B are connected to each other in series. Of course, these LED modules 100A and 100B may be connected in parallel.

Hereinafter, a manufacturing process of the LED assembly according to the present invention will be described with reference to FIGS. 7 to 9. In these drawings, Figure 7 is a cross-sectional view showing a step of manufacturing a substrate portion of the LED assembly according to the invention, Figure 8 is a cross-sectional view showing a step of manufacturing a LED package of the LED assembly according to the invention, Figure 9 Fig. 1 is a cross-sectional view showing a substrate portion and an LED package assembly process of the LED assembly according to the present invention step by step.

First, as shown in FIG. 7A, a metal plate is prepared, and a recess 134 is formed in the metal plate to form a substrate 132.

Subsequently, as shown in FIG. 7B, an insulating layer 136 is formed on the surface of the substrate 132 including the recess 134.

Then, as illustrated in FIG. 7C, circuit patterns 138 and 140 are formed through deposition, plating, or screen printing. A gap 139 of a predetermined dimension is maintained between the circuit patterns 138 and 140. The substrate portion 130 thus obtained has the same form as the substrate portion 130 of FIG. 3.

On the other hand, as shown in FIG. 8A, a pair of leads 112 and 114 having a predetermined interval are prepared, and as shown in FIG. 8B, an LED chip ( 116 is seated and electrically connects LED chip 116 with leads 112 and 114 via wire 118. Meanwhile, the LED chip 112 may be connected to the lead 112 in the form of a flip chip by solder bumps.

Subsequently, as shown in FIG. 8C, the package body 120 is formed of a transparent resin, and then the leads 112 and 114 are cut along the cutting line L _T , thereby cutting the LED of FIG. 8D. Obtain package 110. This LED package 110 is the same form as the LED package 110 of FIG.

The LED package 110 and the substrate unit 130 obtained as described above are assembled into one according to the process of FIG.

First, as shown in FIG. 9A, the solder paste 141 is applied to a part of the circuit patterns 138 and 140 located at the bottom of the neck 134, and then the leads 112 and 114 of the LED package 110 are applied. The LED package 110 is inserted into the recess 134 in the direction of the arrow A so that) may contact the circuit patterns 138 and 140, respectively. Then, the leads 112 and 114 and the circuit patterns 138 and 140 are coupled through the reflow process to fix the LED package 110 to the recess 134. Typical reflow process is 210 to 260? It is carried out at a temperature for approximately 100 seconds, more preferably at a temperature of 240 to 250 ℃ for about 30 seconds. Alternatively, the adhesive may be applied to regions other than the circuit patterns 138 and 140, and then the LED package 110 may be inserted into the recess 134 to couple the LED package 110 to the substrate 130.

Subsequently, as shown in FIG. 8B, the transparent resin film 150 and the diffusion plate 160 are attached to the combined configuration of the LED package 110 and the substrate unit 130 in the direction of an arrow A, respectively. An LED assembly 100 as shown in FIG. 8C is obtained. This LED assembly 100 has the same shape as the LED assembly 100 of FIGS. 3 and 4. That is, the resin film 150 becomes the resin layer 150 of FIGS. 3 and 4. On the other hand, alternatively, the transparent resin may be applied to the surface of the combined configuration of the LED package 110 and the substrate portion 130, and then the diffusion plate 160 may be attached thereon. In either case, the resin film or the transparent resin preferably contains a ultraviolet absorber or a fluorescent substance for converting short wavelength light into multiple wavelengths.

On the other hand, a slight modification of the above-described process can obtain the LED assembly 10 of FIG. That is, the process of FIG. 8 including forming a plurality of recesses in a substrate, forming an insulating layer and a pattern in each recess in the form of FIG. 5, and then inserting a plurality of LED packages obtained by the process of FIG. 8 is performed. The LED assembly 10 of 5 can be manufactured.

Hereinafter, a mass manufacturing process of the LED assembly according to the present invention will be described with reference to FIG. 10. On the other hand, Figure 10 is a cross-sectional view showing some steps of the bulk LED package manufacturing process of the LED assembly according to the present invention.

That is, as shown in FIG. 10A, a frame sheet 111 having a plurality of lead 112 and 114 pairs is prepared, and then, the LED chip 116 is mounted on each lead 112, and the wire 118 is provided. Electrical connections to the furnace leads 112 and 114. Meanwhile, in FIG. 10A, H is a guide hole for placing and fixing the frame sheet 111, and L _T is a cutting line for a cutting operation subsequent to the resin molding operation.

Subsequently, as shown in FIG. 10B, the resin is molded to form the encapsulation body 120. Subsequently, cutting along the cutting line L _{T results} in the LED package 110 as shown in FIGS. 3 and 4, and the cut encapsulation body 120 becomes the package body 120 of FIGS. 3 and 4.

In this way, a plurality of LED packages 110 can be obtained through a single operation. The LED package 110 thus obtained may be inserted into a substrate having one recess, thereby manufacturing the LED assembly 100 of FIGS. 3 and 4, and as described above, the LED package 110 may be inserted into a substrate having a plurality of recesses. It is also possible to obtain the LED assembly 10 as shown in FIG.

According to the present invention as described above, by inserting the LED package on the metal substrate to implement the LED assembly, not only can easily remove the heat generated from the LED chip, but also can reduce the size of the LED assembly. In addition, the concave portion of the substrate functions as a reflection cup for reflecting light generated from the LED chip upwards, thereby simplifying the overall configuration. In addition, when the diffusion plate is installed on the surface of the LED package and the substrate portion through the transparent resin layer, light generated from the LED chip may be uniformly emitted upward. In this case, if the transparent resin layer contains a ultraviolet absorber or a fluorescent material for converting short wavelength light into multiple wavelengths, multi-wavelength light can be obtained even using a short wavelength LED chip.

Although the above has been described with reference to the preferred embodiments of the present invention, those skilled in the art may vary the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. It will be understood that modifications and variations can be made.

Claims (11)

A substrate portion having a metal substrate having a recess formed on one surface thereof, an insulating layer provided on one surface of the metal substrate including the recess portion, and a circuit pattern formed on the bottom of the insulating layer including the recess portion; An LED package inserted into a recess of the substrate part having a pair of leads electrically connected to the circuit pattern and spaced from each other, an LED chip electrically connected to the leads, and a transparent package body encapsulating the leads and the LED chips; ; And LED assembly comprising a coupling means for coupling the LED package to the substrate portion. The LED assembly of claim 1, wherein the coupling unit is a solder to couple the circuit pattern and the lead, respectively. The LED assembly according to claim 1, wherein the coupling means is an adhesive for coupling the LED package to the recess. The LED assembly of claim 2 or 3, further comprising a diffusion plate attached to one surface of the substrate to cover the LED package. The LED assembly of claim 4, further comprising a transparent resin provided between the diffusion plate and the LED package. 6. The LED assembly of claim 5, wherein the transparent resin contains a fluorescent material that converts short wavelength light into multi wavelength light. The LED assembly according to claim 1, wherein the recessed portion is plural and the LED package is the same number as the recessed portion. The LED assembly of claim 1, wherein the lead of the LED package extends from the bottom of the package body to the side wall and a circuit pattern in the recess is formed on the inner wall of the recess. The LED assembly of claim 1, wherein the coupling unit is a diffusion plate attached to one surface of the substrate to cover the LED package. 10. The LED assembly of claim 9, further comprising a transparent resin provided between the diffuser plate and the LED package. The LED assembly of claim 10, wherein the transparent resin contains a fluorescent material that converts short wavelength light into multi-wavelength light.

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