KR20090005346U - Lead Frame Package for LED Device and LED Package using the same - Google Patents

Abstract

The lead frame package for an LED device according to the present invention has a first lead having a first recessed portion formed on an upper surface and a second recessed portion separating the lower surface to both sides, and disposed around the first recessed portion and separated by a groove. At least one second lead electrically separated from the first lead, the first package body filling the separation groove and the second recess and integrally forming the first lead and the second lead, and an upper portion of the first package body. Including an extended second package body, the lower surface of the first lead and the second lead is located on the lower surface of the first package body is exposed to the outside, the second package body includes a first recess portion A hollow part is formed such that the inner end of the upper surface of the first lead and the inner end of the upper surface of each of the second leads adjacent to the first concave portion are exposed to the outside.

The lead frame package for an LED device according to the present invention has an advantage that the plastic resin is molded into upper and lower portions of the lead frame, the second recess, and the cocking groove, thereby improving reliability of peeling. In addition, since the portion in which the LED device is mounted is a concave portion and has a heat dissipation structure exposed on the outer surface of the package body, the external shape is compact and the mounting of the LED package to the substrate is easy.

Leadframe Package, LED Package

Description

Lead frame package for LED device and LED package using the same {Lead Frame Package for LED Device and LED Package using the same}

The present invention relates to a lead frame package for an LED device and an LED package using the same. More particularly, the present invention provides a lead frame package for an LED device and a LED package using the same. will be.

Generally, a light emitting diode (LED) package includes an LED bonding pad, a lead frame including lead wires, an LED mounted on the LED bonding pad, and a package body for packaging them by a molding process. The package body is made of a material such as plastic, ceramic or other insulating material.

Since the LED package has a characteristic in which about 70% of power consumption is consumed by heat in an operating state, excessive heat generation causes a fatal effect on the performance and lifespan of the LED device and the peripheral device to which the LED package is applied. Therefore, the heat dissipation structure must be provided in the LED package for the safety of the LED element and the peripheral device.

To this end, a conventional LED package has a structure in which a metal LED bonding pad is exposed to the bottom of the package body or extended to the side of the package body as described in the prior art of the following [1], or a thick or separate bonding pad is provided. Although a metal plate is attached to the bottom surface of the LED bonding pad and the like, all of these structures have disadvantages such as inefficient heat dissipation structure, physical weakness, or inconsistency.

Therefore, [1] proposes a new lead frame structure to solve this problem. However, these structures have a problem that the mounting structure of the LED package is limited due to the heat dissipation pads protruding out of the package body, and the mold is complicated by the complicated three-dimensional structure formed at the upper and lower parts, thereby increasing the manufacturing cost and significantly increasing the yield of the production line. There is a problem of lowering, and this problem is further exacerbated when a plurality of lead wires are provided.

In addition, the structure proposed in [1] has a thick thickness of the LED package itself because it is required that the thickness of the lead frame is 0.4 to 0.76 mm or more in order to improve the bonding force between the lead frame and the package body and to extend the moisture absorption path. Accordingly, there is a problem in that the product to which the LED package is applied is also thickened, which adversely affects the compactness and slimming of the product.

[Document 1] Republic of Korea Patent Registration No. 10-0708004 (2007. 4. 16. registration announcement)

The present invention is to solve the above-mentioned problems of the prior art, an object of the present invention is to provide a lead frame package and a LED package using the same, which is simple in shape, easy to compact and slim product. .

In addition, another object of the present invention is to provide a lead frame package having a high reliability for peeling and heat dissipation and an LED package using the same despite the simple shape as described above.

In order to achieve the above object, a lead frame package for an LED device according to the present invention is a first lead having a first recessed portion formed on the upper surface and a second recessed portion separating the lower surface to both sides, the first recess At least one second lead disposed around the part and electrically separated from the first lead by a separation groove, the first package body filling the separation groove and the second recess part to integrally form the first lead and the second lead; And a second package body extending to an upper portion of the first package body, wherein lower surfaces of the first and second leads are positioned on a lower surface of the first package body and are exposed to the outside. The package body is characterized in that the hollow portion is formed such that an inner end of the upper surface of the first lead including the first recess and an inner end of the upper surface of each of the second leads adjacent to the first recess are exposed to the outside.

In addition, a cocking groove may be further formed on an upper surface of each of the first lead and the second lead, and the second package body may be filled in the cocking groove.

In addition, an outer surface of the upper surface outer end of each of the first lead and the second lead and an outer surface connected to the outer surface of the upper surface may be exposed to the outside.

In addition, the first recessed portion is circular, and the second lead is composed of five leads, each inner end of which is arranged in a circle around the first recessed portion, the first lead of the five second leads and neighbors One of the two outer surfaces is aligned in line with the outer surface of the first lead and the other three outer surfaces are aligned in the opposite side.

In addition, the hollow portion is characterized in that the upper diameter is conical shape larger than the lower diameter.

In addition, the first lead and the second lead is characterized in that the nickel strike plating layer, the silver strike plating layer and the silver plating layer are sequentially formed on the upper and lower surfaces of the member made of a copper alloy, respectively.

In addition, the LED package according to the present invention is any one of the above-described lead frame package, at least one LED element mounted on the first recess portion and the first lead and the second lead of the LED element exposed inside the hollow portion And bonding wires electrically connected to the inner ends, respectively.

In addition, a stepped portion having a predetermined depth is formed at an edge of the hollow portion, and the stepped portion has a hemispherical lens for passing light emitted from the LED element.

The lead frame package for LED devices according to the present invention can significantly reduce the defect rate in the molding step because the grooves separating each lead are sufficiently large, and the upper and lower parts of the lead frame are simple to manufacture a mold. The advantage is that the cost can be reduced.

In addition, the lead frame package for the LED device according to the present invention is a structure in which the plastic resin is molded in the upper and lower parts, the second concave part and the cocking groove of the lead frame, it is possible to improve the reliability of peeling in the upper and lower direction and transverse direction There is an advantage.

In addition, the lead frame package according to the present invention has a concave portion in which the LED element is mounted and has a heat dissipation structure exposed on the outer surface of the package body, so that the external shape is compact and the mounting of the LED package to the substrate is easy. There is this.

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

1A and 1B are respectively a top perspective view and a bottom perspective view of a lead frame strip according to an embodiment of the present invention. The lead frame 1 according to the present embodiment is produced in the form of a strip in which a plurality of lead frames 1 are connected to each other by a connection line 2, and each lead frame 1 is a lead frame package which will be described later. After the molding process is completed is cut along the cutting lines (L1, L2) to be individualized.

In the present embodiment, as an example, a strip consisting of two columns is described, but the number of columns and rows may be increased or decreased as necessary.

Meanwhile, each lead frame 1 includes a first lead 5 having a circular first recessed portion 3 formed on an upper surface and a second recessed portion 4 separating the lower surface to both sides, and the first lead 5. The first lead 5 and the second lead 7 is arranged around the recess 3 and electrically separated from the first lead 5 by the separating groove 6. Each of the second leads 7 supplies power for driving the plurality of LED elements mounted on the first recesses 3 as described later.

At this time, the inner end (8a) of the first lead (5) that is not connected to the connecting line (2) is a circular shape concentric with the first concave portion (3), the second lead not connected to the connecting line (2) (7) Each inner end 9a is arranged in the form of surrounding the circumference of the first recess 3 formed in the first lead 5 in a circular manner.

In addition, a caulking groove 23 is formed in the upper surface of each of the first lead 5 and the second lead 7 in which a plastic resin is filled to prevent peeling, as will be described later. In the present exemplary embodiment, the case where the number of lead wires is six (that is, one first lead and five second leads) has been described as an example, but may be increased or decreased as necessary or depending on the number of LED elements to be mounted. .

The lead frame 1 of the present invention described above is formed in the molding step because the size of the separation groove 6 separating the first lead 5 and the second lead 7 is large enough not to be affected by the wear of the mold. The defect rate of the can be significantly reduced, and since the upper and lower shapes of the lead frame 1 are simple, there is an advantage that the cost required for manufacturing the mold can be reduced.

Figure 2 is a cross-sectional view showing the structure of the material used in the lead frame 1 according to an embodiment of the present invention. In the lead frame 1 according to the present embodiment, a nickel strike layer 11 is formed on upper and lower surfaces of the main member 10 made of a copper alloy, and a silver strike layer 11 is formed on each upper portion. 12 and a silver plating layer 13 are sequentially formed.

The main member 10 of the copper alloy used in the present embodiment preferably has a copper content of at least 95% or more in order to enhance electrical and thermal conductivity. When the LED package is formed as described below, the lead frame 1 and In order to maintain a contact length such that the package bodies made of plastic resin do not peel from each other, the thickness is preferably about 0.4 mm.

In addition, the nickel strike plating layer 11 and the silver strike plating layer 12 increase the adhesiveness of the silver plating layer 13 when electroplating silver on the main member 10, and uniform the entire surface of the main member 10. Is formed to allow electrodeposition to occur.

3A and 3B are a plan view and a bottom view, respectively, of a leadframe package according to an embodiment of the present invention, and FIG. 4 is a cross-sectional view of part A-A of FIG. 3A.

The lead frame package 1a according to the present embodiment is filled in the lead frame 1, the separation groove 6 and the second recess 4 of the lead frame 1, and thus, the first lead 5 and the 5. And a second package body 22 extending upwardly of the first package body 21 and integrally molding the two second leads 7.

At this time, the first package body 21 and the second package body 22 is molded by a general molding process of the plastic resin, in this embodiment PPA resin was used as an example of the plastic resin.

In addition, the lower surfaces 5b and 7b of the first lead 5 and the second lead 7 integrally formed by the first package body 21 are the lower surface 21b of the first package body 21. It is located in the exposed to the outside, preferably on the same plane as the lower surface (21b) of the first package body (21).

Among the lower surfaces 5b of the first leads 5 which are exposed to the outside, the surface facing the first recess 3 in which the LED elements are mounted, as described below, emits heat generated during the operation of the LED package to the outside. The lower surface 5b of the first lead 5 and the lower surface 7b of each of the second leads 7 function as separate heat sinks, and at the same time, a substrate on which the LED package is mounted. And can be electrically connected.

On the other hand, the second package body 22 has a circular shape around the inner end 8a of the upper surface 5a of the first lead 5 including the first recess 3 and the first recess 3. The hollow part 30 is formed so that the inner end 9a of the upper surface 7a of each of the arranged second leads 7 is exposed to the outside, and the hollow part 30 has a larger upper diameter than the lower diameter. It is formed in a conical shape so that light emitted by the LED element can be emitted to the outside at a direct angle of about 120 °.

In addition, a stepped portion 31 having a predetermined depth having a hemispherical lens is formed on the edge of the hollow portion 30.

In addition, the outer ends 8b and 9b of the upper surfaces 5a and 7a of the first lead 5 and the second lead 7 which are not covered by the first package body 21 and the second package body 22. ) And the outer surfaces 5c and 7c which are in contact with the outer ends 8b and 9b of the upper surfaces 5a and 7a, respectively, are exposed to the outside and thus serve as additional heat sinks during the operation of the LED package.

In addition, after the molding process of the lead frame package 1a is completed, each of the lead frame packages 1a is cut along the cutting lines L1 and L2 of FIG. Two outer surfaces 7c adjacent to the first lead 5 are aligned in line with the outer surface 5c of the first lead 5, and the remaining three outer surfaces 7c are aligned in the opposite side. do.

The lead frame package 1a of the present invention described above is formed by the first package body 21 filled in the second recess 4 in the case of the first lead 5 and the second package body 22 at the upper portion thereof. Since the structure is molded to the upper and lower portions of the one lead 5, it is possible to secure reliability against peeling in the vertical direction.

In addition, since the first lead 5 has a structure in which the first package body 21 and the second package body 22 are respectively filled in the second concave portion 4 and the cocking groove 23, the peeling in the transverse direction is performed. It also has the advantage of ensuring reliability.

On the other hand, even in the case of the second lead 7 is a structure that is molded to the upper and lower portions of the second lead 7 by the first package body 21 and the second package body 22 having a step is formed in the peeling of the vertical direction It is possible to secure the reliability, and also by the structure in which the second package body 22 is filled in the cocking groove 23, it is possible to ensure reliability even in the transverse direction.

FIG. 5 is a cross-sectional view illustrating three LED devices 40 mounted on a lead frame package 1a according to an embodiment of the present invention. As shown in FIG. 5, the three LED elements 40 mounted on the first recesses 3 of the first leads 5 are respectively the first leads 5 and the second leads by the bonding wires 41. It is connected to (7).

The bonding wire 41 electrically connects two electrodes provided in each LED element 40 to any one of the first lead 5 and the second lead 7, respectively. And an externally applied current are transmitted to each LED element 40 through the second lead 7.

In this case, in the present embodiment, although the bonding wire 41 is used to electrically connect any one of the three LED elements 40 to the first lead 5, the electrode of the LED element 40 is provided below. It is also possible to connect electrically to the back surface 1st concave part 3 by using a conductive paste.

On the other hand, the three LED elements 40 are configured by the LED element 40 which emits red, blue and green light, respectively, it is preferable to enable the light of various colors by the combination thereof.

In the present embodiment, as an example, the three LED elements 40 emit light of different colors, but if necessary, the number of LED elements 40 may be mounted differently, and the color of light emitted may be seen. Of course, it can be configured differently from the embodiment.

As described above, in the lead frame package 1a according to the present invention, since the portion in which the LED element 40 is mounted is formed as a recess (that is, the first recess 3), the LED package is described as described below. When formed, there is an advantage that the thickness of the LED package can be made thinner than the prior art.

In addition, since the lead frame package 1a according to the present invention is a heat dissipation structure exposed to the outer surface of the first package body 21 rather than a heat dissipation structure that protrudes to the outside, the external shape is compact and the mounting of the LED package to the substrate This has the advantage of being easier.

Therefore, the leadframe package 1a according to the present invention may enable compactness and slimming of the LED package and products using the same.

6 is a cross-sectional view showing an LED package 1b according to an embodiment of the present invention. As described above, when the mounting of the LED element 40 on the first recess 3 by the bonding wire 41 is completed, the second package is used to fix the LED element 40 and the bonding wire 41 contact point. The secondary molding body 50 is formed in the hollow part 30 of the body 22 through a molding process.

In this embodiment, transparent silicon is used as an example of the secondary molding member 50, which is to facilitate the emission of light emitted from the LED device 40 to the outside, and may be mixed and molded as needed. have.

In addition, the stepped portion 31 provided at the upper portion of the hollow part 30 is provided with a dome-shaped transparent lens 51, so that the light passing through the secondary molding body 50 is emitted to the outside over the omnidirectional to direct high brightness The advantage is that you can.

In the present embodiment, the transparent lens 51 is made of a transparent epoxy resin, but is not limited thereto, and may be preferably implemented in various materials within a range performing the same function.

In addition, the transparent lens 51 may be manufactured separately and fitted to the stepped portion 31, or may be molded by a molding process as necessary.

1A and 1B are a top perspective view and a bottom perspective view, respectively, of a lead frame strip according to an embodiment of the present invention;

Figure 2 is a cross-sectional view showing the structure of the material used in the lead frame according to an embodiment of the present invention,

3A and 3B are a plan view and a bottom view, respectively, of a lead frame package according to an embodiment of the present invention;

4 is a cross sectional view taken along line A-A of FIG. 3A;

5 is a plan view showing a form in which the LED device is mounted on a lead frame package according to an embodiment of the present invention, and

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

* Description of symbols on the main parts of the drawings *

3: first recessed part 4: second recessed part

5: Lead 1 7: Lead 2

21, 22: first and second package body 23: cocking groove

30: hollow part 40: LED element

50: secondary molding 51: transparent lens

Claims (8)

A first lead having a first recessed portion formed on the upper surface and a second recessed portion separating the lower surface on both sides; At least one second lead disposed around the first recess and electrically separated from the first lead by a separation groove; A first package body filled in the separation groove and the second recess to integrally mold the first lead and the second lead; And Including a second package body extending to the upper portion of the first package body, Lower surfaces of the first and second leads are positioned on the lower surface of the first package body and exposed to the outside. The second package body is a lead frame characterized in that the hollow portion is formed so that the inner end of the upper surface of the first lead including the first recess portion and the inner end of the upper surface of each of the second leads adjacent to the first recess portion is exposed to the outside. package. The method of claim 1, Cocking grooves are further formed on an upper surface of each of the first and second leads, And the second package body is filled in the cocking groove. The method of claim 2, The lead frame package, characterized in that the outer surface of the upper end and the outer surface in contact with the outer end of the upper surface of each of the first and second leads exposed to the outside. The method of claim 3, The first recess is circular, The second lead consists of five leads, each inner end of which is arranged in a circle around the first recess, Lead frame package, characterized in that the two outer surfaces adjacent to the first lead of the five second leads is aligned in line with the outer surface of the first lead, the remaining three outer surfaces are arranged in a line on the opposite side . The method of claim 4, wherein The hollow part is a lead frame package, characterized in that the upper diameter is larger than the lower diameter conical. The method of claim 5, The first lead and the second lead are formed on the upper and lower surfaces of the main member made of a copper alloy, respectively, a nickel strike plating layer, a silver strike plating layer, and a silver plating layer, characterized in that the silver plating layer is formed. Leadframe package. A leadframe package according to any one of claims 1 to 6; At least one LED element mounted on the first recess; And And a bonding wire electrically connecting the LED element to inner ends of the first lead and the second lead exposed inside the hollow part, respectively. The method of claim 7, wherein A stepped portion having a predetermined depth is formed at an edge of the hollow portion, and the stepped portion is provided with a hemispherical lens for passing the light emitted by the LED element.

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