KR20080017522A - Light emitting diode package and method of manufacturing the same - Google Patents

Abstract

A light emitting diode package and a method for manufacturing the same are provided to radiate efficiently heat by forming Ag on a surface of a lead frame in a hole of the lead frame. A pair of lead frames(110) are formed with a first lead frame(110a) and a second lead frame(110b) having a hole. A thermal conducting reflection member is formed on a surface of the first lead frame, a surface of the second lead frame, and the hole of the second lead frame. A package mold(120) is formed to receive a part of the lead frame and to define a molding material filling space. An LED chip(130) is mounted at an upper part of the hole in which the thermal conducting reflection member of the second lead frame is formed. A wire(140) is formed to connect electrically the LED chip with the lead frame. A molding material(150) fills the package mold in order to protect the LED chip and the wire.

Description

Light emitting diode package and method of manufacturing the same

1 is a cross-sectional view showing the structure of an LED package according to the prior art.

FIG. 2 is a cross-sectional view illustrating a heat dissipation path from the LED chip of FIG. 1. FIG.

3 is a cross-sectional view showing the structure of an LED package according to an embodiment of the present invention.

4A to 4F are cross-sectional views sequentially illustrating the method of manufacturing the LED package according to the embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

110a: first lead frame 110b: second lead frame

110: lead frame 120: package mold

130: LED chip 140: wire

150: molding material 200: Ag

300: hole

The present invention relates to a light emitting diode package and a method of manufacturing the same, and more particularly, to a light emitting diode package and a method of manufacturing the same that can improve the heat dissipation ability.

Recently, light emitting diode (LED) devices using compound semiconductor materials such as GaAs, GaN, and AlGaInP have been developed, and thus, light sources of various colors can be realized. Factors that determine the characteristics of LED products include color, brightness and light conversion efficiency. The characteristics of such LED products are primarily determined by the compound semiconductor materials and structures thereof used in the LED devices, but are also greatly influenced by the structure of the package for mounting the LED chips as secondary elements.

In addition to the primary elements such as the material or structure of the LED chip to obtain the luminous effect according to the user's requirements, it is necessary to improve the structure of the LED package and the material used therefor. In particular, as the use range of the LED package is extended to various fields such as indoor and outdoor lighting devices, automotive headlights, and back light units of liquid crystal displays (LCDs), high efficiency and high heat dissipation characteristics are required.

If the heat generated by the LED chip is not effectively dissipated from the LED package, the temperature of the LED chip becomes high, which deteriorates the characteristics of the LED chip and decreases its lifespan. Therefore, efforts are being made to effectively dissipate heat generated from LED chips in high power LED packages.

In order to improve the heat dissipation efficiency of the LED package, a lead frame made of Cu is conventionally used.

Hereinafter, an LED package using a lead frame made of Cu according to the prior art will be described in detail with reference to FIGS. 1 and 2.

1 is a cross-sectional view showing the structure of an LED package according to the prior art, Figure 2 is a cross-sectional view for explaining a heat dissipation path from the LED chip of FIG.

First, referring to FIG. 1, the LED package according to the related art includes a pair of lead frames 110 formed of a first lead frame 110a and a second lead frame 110b, and the lead frame 110. On the second lead frame 110b which is a lead frame of any one of the package mold 120 and the lead frame 110 inside the package mold 120 while receiving a portion therein and defining a molding material filling space. The LED chip 130 mounted on the wire, a wire 140 for electrical connection between the lead frame 110 and the LED chip 130, and the inside of the package mold 120 is filled in the LED chip 130 And a molding material 150 for protecting the wire 140.

The lead frame 110 is preferably made of Cu excellent in thermal conductivity in order to effectively release heat generated from the LED chip 130.

On the surface of the lead frame 110, an Ag 200 for reflecting light generated from the LED chip 130 is coated.

When the power is applied to the LED chip 130, as shown by the arrow of Figure 2, the heat generated by the operation of the LED chip 130 is outside the package through the lead frame 110 of the Cu material The heat is also emitted to the outside of the package through the Ag (200) coated on the surface of the lead frame (110).

However, recently, a package structure having better heat dissipation capability is required for LEDs for LCD backlight units requiring high power.

Therefore, there is a need in the art for a new way to maximize the effect of improving the heat dissipation capacity of the LED package.

Accordingly, the present invention has been made to solve the above problems, and an object of the present invention is to provide a light emitting diode package and a method of manufacturing the same that can improve heat dissipation capability.

According to an aspect of the present invention, there is provided a light emitting diode package including: a pair of lead frames including a first lead frame and a second lead frame having a hole formed at a portion thereof; A thermally conductive reflecting member formed on a surface of the first lead frame, a surface of the second lead frame, and a hole; A package mold formed to define a molding material filling space while accommodating a portion of the lead frame therein; An LED chip mounted on an upper portion of the hole in which the thermally conductive reflecting member of the second lead frame is formed in the package mold; A wire for electrical connection between the LED chip and the lead frame; And a molding material filled in the package mold to protect the LED chip and the wire.

The thermally conductive reflecting member may be formed of a material having a higher thermal conductivity than the lead frame.

The lead frame is made of Cu, and the thermally conductive reflecting member is made of Ag.

In addition, the hole formed in a portion of the second lead frame is characterized in that it has any one shape selected from the group consisting of a circle, a polygon, and a combination thereof.

In addition, a method of manufacturing a light emitting diode package according to the present invention for achieving the above object comprises the steps of providing a pair of lead frames consisting of a first lead frame and a second lead frame; Forming a hole in a portion of the second lead frame; Forming a thermally conductive reflecting member in a surface of the first lead frame, a surface of the second lead frame, and a hole; Receiving a portion of the lead frame therein to form a package mold defining a molding material filling space; Mounting an LED chip on a hole in which the thermally conductive reflecting member of the second lead frame is formed in the package mold; Connecting the LED chip and the lead frame with a wire; And filling a molding material into the package mold.

The thermally conductive reflecting member may be formed of a material having a higher thermal conductivity than the lead frame.

The lead frame is made of Cu, and the thermally conductive reflecting member is made of Ag.

In addition, the hole formed in a portion of the second lead frame is characterized in that it has any one shape selected from the group consisting of a circle, a polygon, and a combination thereof.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. Like reference numerals designate like parts throughout the specification.

Now, with reference to the drawings with respect to the LED package and its manufacturing method according to an embodiment of the present invention will be described in detail.

Embodiment of Structure of LED Package

First, the LED package according to the embodiment of the present invention will be described in detail with reference to FIG. 3.

3 is a cross-sectional view showing the structure of an LED package according to an embodiment of the present invention.

As shown in FIG. 3, the LED package according to the embodiment of the present invention includes a pair of lead frames 110 formed of a first lead frame 110a and a second lead frame 110b, and the lead frame ( While accommodating a portion of the inside of the package mold 120 formed to define the molding material filling space, and the lead frame of any one of the pair of lead frames 110 located inside the package mold 120 The LED chip 130 mounted on the second lead frame 110b, the wire 140 for electrical connection between the LED chip 130 and the lead frame 110, and the inside of the package mold 120. Filled in to include a molding material 150 to protect the LED chip 130 and the wire 140.

The package mold 120 may be made of plastic, etc., which may be formed by a general pre-molding process.

As the LED chip 130, a conventional GaN-based LED chip may be used, and the wire 140 is generally made of Au.

In addition, the molding material 150 may be made of a light-transmitting resin containing a transparent material or a phosphor according to the color of the LED chip 130 to be implemented.

In addition, the lead frame 110 is preferably made of Cu excellent in thermal conductivity in order to effectively release heat generated from the LED chip 130 as described above.

In particular, in the present embodiment, the hole 300 is additionally formed in a portion of the second lead frame 110b in which the LED chip 130 is mounted. The hole 300 is preferably formed in the lower portion of the LED chip 130, which may be formed through the process of punching.

In addition, the hole 300 may have a circular shape or may have a rectangular shape. In addition, the shape of the hole 300 is not limited to the shape as described above, and includes, for example, polygons such as pentagons and hexagons, and combinations of the circles and polygons within the scope of the present invention. It can be variously modified.

In addition, in the surfaces of the first lead frame 110a and the second lead frame 110b and the hole 300 of the second lead frame 110b, the thermal conductivity is higher than that of the Cu forming the lead frame 110. A thermally conductive reflecting member made of a large material such as Ag 200 is formed.

When comparing the thermal conductivity of Cu constituting the lead frame 110 and Ag constituting the thermally conductive reflecting member, Cu is 398 W / mK and Ag is 418 W / mK at a temperature of 25 ° C., It can be seen that Ag has greater thermal conductivity than Cu.

At this time, when the power is applied to the LED chip 130, as shown by the arrow of Figure 3, the heat generated from the LED chip 130 to the outside of the package through the lead frame 110 of the Cu material The heat is also emitted to the outside of the package through the Ag 200 formed in the surface of the first lead frame 110, the surface of the second lead frame, and the hole 300.

As described above, the Ag 200 having a thermal conductivity greater than Cu is formed on the surface of the lead frame 110 to reflect the light generated from the LED chip 130, and also in the LED chip 130. The generated heat is released out of the package.

In particular, according to an embodiment of the present invention, Ag 200 having a thermal conductivity greater than Cu is additionally formed in the hole 300 formed in the second lead frame 110b under the LED chip 130. Since the heat generated by the LED chip 130 may be more efficiently emitted to the outside through the Ag 200 in the hole 300.

Embodiment of the manufacturing method of the LED package

Hereinafter, a method of manufacturing an LED package according to an embodiment of the present invention will be described in detail with reference to FIGS. 4A to 4F.

4A through 4F are cross-sectional views sequentially illustrating a method of manufacturing an LED package according to an exemplary embodiment of the present invention.

First, as shown in FIG. 4A, a pair of lead frames 110 including a first lead frame 110a and a second lead frame 110b are provided. The lead frame 110 is preferably made of Cu.

Next, as shown in FIG. 4B, a hole 300 is formed in a portion of the second lead frame 110b which is one of the pair of lead frames 110.

The hole 300 is preferably formed in the lead frame portion in which the LED chip 130, which will be described later, is mounted, and may be formed through a punching process. In addition, the hole 300 may have a circular shape or may have a rectangular shape. In addition, the shape of the hole 300 is not limited to the shape as described above, within the technical scope of the present invention, for example, a combination of polygons such as pentagons and hexagons, and combinations of the circles and polygons, etc. It can be variously modified, including.

4C, Cu constituting the lead frame 110 is formed in the surface of the first lead frame 110a, the surface of the second lead frame 110b, and the hole 300. A thermally conductive reflecting member made of a material having a higher thermal conductivity, such as Ag (200), is formed.

Here, according to the embodiment of the present invention, not only the surface of the lead frame 110, but also the Ag (200) having a greater thermal conductivity than Cu is formed in the hole 300 of the lead frame 110, The heat generated by the LED chip 130 to be described later may be more efficiently emitted to the outside through the Ag 200 in the hole 300.

Next, as shown in FIG. 4D, a package mold 120 defining a molding material filling space is formed while accommodating a part of the lead frame 110 therein. The package mold 120 may be generally formed by a pre-molding process or the like.

Next, as shown in FIG. 4E, the LED chip 130 is formed on the second lead frame 110b which is one of the pair of lead frames 110 positioned in the package mold 120. Implement At this time, the LED chip 130 is mounted on the upper portion of the hole 300 so that heat generated when the power is applied can be well discharged to the outside of the package through the Ag (200) inside the hole (300). It is preferable.

Next, the LED chip 130 and the lead frame 110 are connected by a wire 140. Here, the wire 140 may be made of Au.

Then, as shown in FIG. 4F, the molding material 150 is filled in the package mold 120. The molding material 150 may be made of a light-transmitting resin containing a transparent material or a phosphor according to the color of the LED chip 130 to be implemented, which is the LED chip 130 and the inside of the package mold 120 and Protect the wire 140.

As described above, according to the embodiment of the present invention, the hole 300 is additionally formed in the lead frame 110 under the LED chip 130, and then the Ag 200 is formed on the surface of the lead frame 110. By forming Ag 200 in the hole 300 and at the same time, heat generated in the LED chip 130 can be efficiently discharged to the outside through the Ag 200 formed in the hole 300. By doing so, there is an effect that can further improve the heat dissipation capability of the LED package.

Therefore, the present invention can prevent deterioration of characteristics and shorten the life of the LED chip 130 due to heat, and can implement an LED package that can be applied to various fields requiring high output, such as an LCD backlight unit.

Although the preferred embodiments of the present invention have been described in detail above, those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Accordingly, the scope of the present invention is not limited to the disclosed embodiments, but various modifications and improvements of those skilled in the art using the basic concept of the present invention as defined in the following claims also belong to the scope of the present invention.

As described above, according to the LED package and the method of manufacturing the same according to the present invention, by additionally forming a hole in the lead frame of the lower LED chip, by forming Ag in the surface and the hole of the lead frame, generated in the LED chip The heat can be released to the outside through the Ag formed in the hole, it is possible to further improve the heat dissipation capacity of the LED package.

Therefore, the present invention can prevent deterioration of characteristics and shorten the life of the LED chip due to heat, and can implement an LED package applicable to various fields requiring high output, such as an LCD backlight unit.

Claims (8)

A pair of lead frames comprising a first lead frame and a second lead frame having holes formed in a portion thereof; A thermally conductive reflecting member formed on a surface of the first lead frame, a surface of the second lead frame, and a hole; A package mold formed to define a molding material filling space while accommodating a portion of the lead frame therein; An LED chip mounted on an upper portion of the hole in which the thermally conductive reflecting member of the second lead frame is formed in the package mold; A wire for electrical connection between the LED chip and the lead frame; And A molding material filled in the package mold to protect the LED chip and the wire; Light emitting diode package comprising a. The method of claim 1, The thermally conductive reflecting member is a light emitting diode package, characterized in that made of a material having a higher thermal conductivity than the lead frame. The method of claim 2, The lead frame is made of Cu, the thermally conductive reflector is a light emitting diode package, characterized in that made of Ag. The method of claim 1, The hole formed in the portion of the second lead frame, LED package, characterized in that it has any one shape selected from the group consisting of a circle, a polygon, and a combination thereof. Providing a pair of lead frames consisting of a first lead frame and a second lead frame; Forming a hole in a portion of the second lead frame; Forming a thermally conductive reflecting member in a surface of the first lead frame, a surface of the second lead frame, and a hole; Receiving a portion of the lead frame therein to form a package mold defining a molding material filling space; Mounting an LED chip on a hole in which the thermally conductive reflecting member of the second lead frame is formed in the package mold; Connecting the LED chip and the lead frame with a wire; And Filling a molding material into the package mold; Method of manufacturing a light emitting diode package comprising a. The method of claim 5, The thermally conductive reflecting member is a method of manufacturing a light emitting diode package, characterized in that made of a material having a greater thermal conductivity than the lead frame. The method of claim 6, The lead frame is made of Cu, the thermally conductive reflector is a light emitting diode package, characterized in that made of Ag. The method of claim 5, The hole formed in the portion of the second lead frame, LED package, characterized in that it has any one shape selected from the group consisting of a circle, a polygon, and a combination thereof.

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