KR100855356B1

KR100855356B1 - Led package base having multi-chip and lighting apparatus using the same

Info

Publication number: KR100855356B1
Application number: KR1020070028847A
Authority: KR
Inventors: 박찬익
Original assignee: 주식회사 옵토필
Priority date: 2007-03-23
Filing date: 2007-03-23
Publication date: 2008-09-04

Abstract

A multi-chip light emitting diode package and an illumination apparatus using the same are provided to increase an optical output by composing a plurality e of light emitting diode chips into one package. A heat-radiating plate(10) includes a plurality of chip bonding regions formed on an upper surface thereof in order to radiate heat generated from light emitting diode chips(40) mounted on the chip bonding regions. An electric insulating layer(12) is formed on the heat-radiating plate in order to expose the chip bonding regions. A lead frame includes at least one inner lead line which is commonly adjacent to the chip bonding regions. A plastic molding body(30) is formed to fix an end of the inner lead line to an upper part of the heat-radiating plate in order to expose wire bonding regions and the chip bonding regions and to form a cavity over the chip bonding regions. The light emitting diode chips are mounted on the chip bonding regions. A plurality of bonding wires(42) are used for connecting electrically the light emitting diode chips with the wire bonding regions. A lens unit is arranged on the light emitting diode chips.

Description

LED package base having multi-chip and lighting apparatus using the same

FIG. 1A is a plan view of a heat dissipation plate for manufacturing a multi-chip LED package according to one embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line 1B-1B ′ of FIG. 1A.

2 is a view showing a lead frame for manufacturing a multi-chip light emitting diode package according to a first embodiment of the present invention.

FIG. 3A is a plan view of the lead frame of FIG. 2 disposed on the heat dissipation plate of FIG. 1A, and FIG. 3B is a cross-sectional view taken along line 3B-3B 'of FIG. 3A, and FIG. 3C is taken along line 3C-3C' of FIG. 3A. It is a cross section.

4A is a plan view showing a package base in which the heat dissipation plate and the lead frame of FIG. 3A are integrated with a plastic molding body, and FIG. 4B is a cross-sectional view taken along the line 4B-4B 'of FIG. 4A, and FIG. 4C is 4C-4C of FIG. 4A. 'It's a cross section.

FIG. 5A is a plan view showing wire bonding of a light emitting diode chip on an exposed heat dissipation plate of the package base of FIG. 4, FIG. 5B is a cross-sectional view taken along line 5B-5B ′ of FIG. 5A, and FIG. 5C is 5C of FIG. 5A. This is a cross-sectional view of the -5C 'line.

FIG. 6 is a cross-sectional view showing an example of a package in which hemispherical lens portions are separately formed on each light emitting diode chip of FIG. 5C.

FIG. 7 is a cross-sectional view illustrating an example of a package in which one hemispherical lens unit is formed on the entire light emitting diode chip of FIG. 5C.

FIG. 8 is a cross-sectional view illustrating an example of a package in which a crown lens part is formed on an entire LED chip corresponding to FIG. 7.

FIG. 9 is a view showing an example of a lighting apparatus in which the package of FIG. 8 is mounted in a reflecting mirror in a forward direction.

FIG. 10 is a view showing an example of a lighting apparatus in which a light emitting diode package according to the present invention is mounted in a reflecting mirror in a reverse direction.

FIG. 11 is a view showing another example of a lighting apparatus in which a light emitting diode package according to the present invention is mounted in a reflecting mirror in a reverse direction.

12A is a plan view of a heat sink for manufacturing a multi-chip LED package according to another embodiment of the present invention, and FIG. 12B is a cross-sectional view taken along the line 12B-12B ′ of FIG. 12A.

FIG. 13A is a plan view of the lead frame of FIG. 2 disposed on the heat dissipation plate of FIG. 12A. FIG. 13B is a cross-sectional view taken along line 13B-13B 'of FIG. 13A, and FIG. 13C is taken along line 13C-13C' of FIG. 13A. It is a cross section.

FIG. 14A is a plan view showing a package base in which the heat dissipation plate and the lead frame of FIG. 13A are integrated with a plastic molding body, and FIG. 14B is a cross-sectional view taken along the line 14B-14B 'of FIG. 14A, and FIG. 14C is a 14C-14C of FIG. 14A. 'It's a cross section.

FIG. 15A is a plan view showing wire bonding of a light emitting diode chip on an exposed heat dissipation plate of the package base of FIG. 14, and FIG. 15B is a cross-sectional view taken along line 15B-15B 'of FIG. 15A, and FIG. 15C is 15C of FIG. 15A. Section taken along line -15C '.

FIG. 16A is a plan view of a heat dissipation plate for manufacturing a multi-chip LED package according to another embodiment of the present invention, and FIG. 16B is a cross-sectional view taken along line 16B-16B ′ of FIG. 16A.

FIG. 17 illustrates a lead frame for manufacturing a multi-chip light emitting diode package corresponding to the heat radiating plate of FIG. 16.

FIG. 18A is a plan view of the lead frame of FIG. 17 disposed on the heat dissipation plate of FIG. 16A, and FIG. 18B is a cross-sectional view taken along the line 18B-18B 'of FIG. 18A.

FIG. 19A is a plan view showing a package base in which the heat dissipation plate and the lead frame of FIG. 16A are integrated with a plastic molding body, and FIG. 19B is a cross-sectional view taken along the line 19B-19B 'of FIG. 19A.

20A is a plan view showing wire bonding of a light emitting diode chip on an exposed heat dissipation plate of the package base of FIG. 19, and FIG. 20B is a cross-sectional view taken along line 20B-20B 'of FIG. 20A.

FIG. 21 is a cross-sectional view illustrating an example of a package in which one hemispherical lens unit is formed on the entire light emitting diode chip of FIG. 20C.

* Explanation of symbols for the main parts of the drawings

10,10 ', 110; Heat release plates 12, 112; Electric insulation film

40; Light emitting diode chip 42; Bonding wire

20, 120; Leadframe 30,130; Plastic molded body

50,52,54,152; Lens sections 60,62,64; Reflector

The present invention relates to a multi-chip LED package and a lighting device using the same. More particularly, the present invention relates to a multi-chip light emitting diode package in which a plurality of light emitting diode chips are mounted in one package, and to an illumination device of an indirect irradiation type that illuminates the emitted light by illuminating the reflector using the same. And a manufacturing method thereof.

The abbreviation of light emitting diode is LED (Light-Emitting Diode). It is a kind of diode that emits light when electric current flows. It is used for indicators or numeric display of general electronic products, and it is very familiar with our life. In the early days, there was a limit of low luminance and color, but now, new light emitting diode raw materials and advanced production technology can realize all colors in the visible light region including white light in the light emitting diodes. Already in developed countries and in Korea, it is widely applied to various signs such as large billboards, emergency lights, traffic signals, passenger cars, signs, interiors, and exhibitions.

In general, the surface-mount LED package is packaged in a simple manner by mounting the LED chip on a flat lead frame or printed circuit board and forming a protective body with a transparent resin. However, advanced LED packages to increase the efficiency of the light emitted from the LED chips and to effectively dissipate heat have a more complex shape. When the light emitted from the light emitting diode chip is effectively collected and the light beam is controlled to increase the light efficiency, the light emitting diode chip should be mounted in a cavity structure such as a light reflecting cup. Such a cavity structure is also effective to apply a fluorescent material on the LED chip for wavelength conversion of the emitted light of the LED chip or to attach a lens while protecting the LED chip and the bonding wire. On the other hand, a large area high output light emitting diode cannot be prevented from deteriorating the light emitting diode chip due to the operation heat of the light emitting diode using a simple lead frame or a printed circuit board. Ultimately, high-end LED packages must have cavities and heat sinks.

However, in most conventional high-power LED packages, there is room for improvement to further utilize the lead frame as a heat dissipation path while increasing the volume ratio of the heat dissipation plate in the limited package volume to effectively dissipate the operating heat of the LED. In addition, various arrangements are required to efficiently mount multi-chips in one package to increase light output and diversify light directing patterns for various applications.

On the other hand, in the conventional lighting lamp using a light emitting diode, the light emitting diode package is positioned in the center of the bottom surface of the parabolic reflector and the light emitting port is mostly directed in the forward direction. Therefore, the emitted light emitted outside the lamp is reflected by the parabolic reflector once or twice or mixed with the light emitted directly without being affected by the parabolic mirror. Such light has a problem that it is difficult to maintain uniformity of light intensity at the irradiation surface. In other words, light is concentrated in the center of the irradiation surface and brightness is weakened along the edge. In addition, there is a problem that the emitted light from the light emitting diode is directly exposed to the field of view to increase the eye fatigue.

SUMMARY OF THE INVENTION The present invention has been proposed to solve the above problems, and the technical problem to be solved by the present invention is to reduce the volume ratio of the heat dissipation plate under a limited package volume in order to effectively discharge the operating heat generated in a plurality of high power LED chips. To provide a maximized multi-chip LED package.

Another object of the present invention is to provide a multi-chip light emitting diode package capable of efficiently implementing monochromatic light or tricolor light in one package.

Another object of the present invention is to provide a multi-chip light emitting diode package capable of maximizing light output and uniformly dispersing light on an irradiation surface.

Another object of the present invention is to provide a light emitting diode illumination device capable of maximizing the light output using the multi-chip light emitting diode package of the present invention as described above and achieving uniform light distribution on an irradiation surface. .

The multi-chip LED package according to the present invention for achieving the technical problems of the present invention, provides a plurality of chip bonding regions on the upper surface, and generates heat generated from the light emitting diode chip mounted on the chip bonding region And a heat dissipation plate for discharging, and an electrical insulation film is formed on the heat dissipation plate while exposing the chip bonding regions. A lead frame including at least one internal lead wire in direct contact with and overlapping with the heat dissipation plate via the electrical insulating layer, and at least one end of which is adjacent to each of the chip bonding regions. It is tightly fixed to the upper surface of the heat dissipation plate, and to form a cavity over the chip bonding regions while exposing the plurality of wire bonding regions and the chip bonding regions formed at the ends of the inner lead line corresponding to the respective chip bonding regions. The plastic molding body is molded. A plurality of light emitting diode chips are mounted in each of the chip bonding regions, and a plurality of bonding wires electrically connecting the light emitting diode chips and the wire bonding regions corresponding thereto, and a lens unit disposed over the light emitting diode chips. do.

The heat radiating plate may be one having a through hole formed at a central portion thereof, or one having no through hole. The heat radiating plate may have various shapes such as a circle, a square, or a polygon having a predetermined thickness. In addition, the chip bonding regions may be arranged at regular intervals, for example, concentrically on the upper surface of the heat dissipation plate.

The lead frame may include at least one pair of inner lead lines facing each other while defining the respective chip bonding regions and at least one inner lead wire connected to each of the inner lead ends. In addition, the lens unit may be formed as a multi-lens unit formed independently for each LED chip or a single lens unit formed over each LED chip. In addition, the lens unit may use a convex spherical lens, or may use a side-emitting type lens unit that allows the light emitted from each LED chip to be irradiated in the lateral direction.

The electrically insulating layer may or may not be removed in the chip bonding region, and a portion of the insulating layer may or may not be exposed in the chip bonding region. In addition, the inner lead line may be bent to be spaced apart from the heat radiating plate near the edge of the heat radiating plate.

On the other hand, LED chip emitting light of the same color may be arranged in the chip bonding areas, and each of the chip bonding areas includes at least one light emitting diode chip emitting red light, green light and blue light. It can also be implemented. The chip bonding regions may include a first bonding region in which a red light emitting diode chip is mounted, a second bonding region in which a green light emitting diode chip is mounted, a third bonding region and a fourth bonding region in which a blue light emitting diode chip is mounted. have.

The red light emitting diode chip, the green light emitting diode chip and the blue light emitting diode chip are each electrically connected to at least one internal lead wire, or the red light and the blue light emitting diode chip are respectively connected to a pair of internal lead wires, and the green light emitting diode chip They may be connected in parallel to a pair of internal lead wires.

On the other hand, when the electrical insulating film is made of a material having a low thermal resistance, for example, a nitride film, a white or silver light reflecting film may be further formed thereon without removing the nitride film. When the electrical insulation layer is removed from the chip bonding region, the electrical insulation layer may be sealed in the plastic molding body so as not to be exposed or extended to the upper surface of the heat dissipation plate so as to be partially exposed from the plastic molding body.

The upper surface of the heat dissipation plate may be composed of a flat surface. In addition, a portion of the upper surface of the heat dissipation plate may include a recessed region, the chip bonding region may be formed in the recess region. The heat radiating plate may be formed of a metal plate or a ceramic plate having good thermal conductivity. The heat dissipation plate may have a fixing member such as a through hole or a fixing groove to be fixed at the correct position of the molding mold in the plastic molding process.

On the other hand, the electrical insulating film may be formed of a white resin film, a photosensitive resin film that can be selectively removed by exposure and development, or may be formed of any one of a nitride film or an oxide film that can be grown on a heat radiating plate of metal. In the case of forming the nitride film or the oxide film, a silver or white light reflecting film having good light reflection efficiency may be further formed in the chip bonding regions without removing the nitride film or the oxide film.

The lead frame includes a pair of inner lead wires facing each other in a form surrounding the chip bonding regions, and ends of the inner lead wires have a shape of an upper surface of the heat dissipation plate so as to extend an overlapping area with the heat dissipation plate. Can be expanded accordingly.

As another alternative, the lead frame may be formed of one inner lead line whose end portion is extended in correspondence with the shape of the top surface of the heat dissipation plate except for the chip bonding region in order to extend the overlapping area with the heat dissipation plate. In this case, the one inner lead wire may be used as one common electrode of the LED chips, and the heat radiating plate may be used as the other electrode.

On the other hand, the LED lighting apparatus according to the present invention for achieving the technical problem of the present invention, a printed circuit board having a bonding pad formed on the upper surface, a multi-chip light emitting diode package mounted on the printed circuit board and the inside It includes a cylindrical groove-shaped reflector for mounting the printed circuit board on which the multi-chip LED package is mounted.

The LED package may include: a heat dissipation plate configured to provide a plurality of chip bonding regions on an upper surface thereof, and to radiate heat generated from the LED chip mounted on the chip bonding region; An electrical insulation film formed on the heat dissipation plate while exposing the chip bonding regions; The heat dissipation layer is directly in contact with and overlaps with the heat dissipation layer, and an end thereof extends from at least one inner lead line and the inner lead line which are commonly adjacent to the respective chip bonding regions, and is connected to the bonding pad of the printed circuit board. A lead frame including external lead wires; The tip of the inner lead wire is fixed to the upper surface of the heat dissipation plate in close contact with each other, and the chip is exposed while exposing the plurality of wire bonding areas and the chip bonding areas formed at the ends of the inner lead wire in correspondence to the respective chip bonding areas. A plastic molded body shaped to form a cavity over the bonding regions; A plurality of light emitting diode chips mounted in each of the chip bonding regions; A plurality of bonding wires electrically connecting the respective LED chips and the wire bonding regions corresponding thereto; And a lens unit disposed on the light emitting diode chips.

The reflector has a semi-spherical inner surface, and the bottom of the printed circuit board may be mounted at the center of the inner bottom of the reflector, and the lens unit may emit light emitted from each light emitting diode chip in a lateral direction. It can comprise a lens part.

The lens unit of the LED package may be mounted to face the lower surface of the reflector. For example, through-holes are formed in the centers of the reflector, the light emitting diode package, and the printed circuit board, the through-holes communicate with each other, and the reflector and the light emitting diode package maintain a constant distance therebetween. It may be configured to further include an external terminal wire connected in the lower surface of the printed circuit board through the installed pipe and the pipe.

The chip bonding regions may include light emitting diode chips that emit light of the same color, or include at least one light emitting diode chip that emits red light, green light, and blue light.

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

The embodiments described below may be modified in many different forms, and the scope of the present invention is not limited to the embodiments described below. The embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art. In the drawings illustrating embodiments of the present invention, the thicknesses of certain layers or regions are exaggerated for clarity of specification, and like numerals in the drawings refer to like elements.

1A to 8 are plan views or cross-sectional views illustrating a multi-chip LED package according to a first embodiment of the present invention, wherein a plurality of light emitting diode chips are formed in one package using a heat dissipation plate having a disc shape. Yes. 6-8 are various examples of a multi-chip light emitting diode package completed according to the first embodiment of the present invention.

FIG. 1A is a plan view of a heat dissipation plate for manufacturing a multi-chip LED package according to a first embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line 1B-1B ′ of FIG. 1A.

1A and 1B, an electric insulation film 12 is formed on the heat dissipation plate 10. A portion of the electrically insulating film 12 is removed to form a chip bonding region 12a. In the present embodiment, a plurality of concentric circles, for example, eight are arranged based on the center of the heat radiating plate 10.

The heat dissipation plate 10 may be a metal plate such as copper (Cu) or aluminum (Al) having good thermal conductivity, and in addition to the metal, such as Ag, Mo, Fe, Ni, W, or an alloy thereof may be used. Furthermore, a ceramic material having excellent thermal conductivity may be used. In addition, although not shown, various shapes may be formed at appropriate positions on the sidewalls or lower portions of the heat radiating plate 10 to stably fix the heat radiating plate 10 in a given mold when molding the plastic molding body 30 shown in FIG. 4. Fixing grooves (not shown) may be formed. In addition, although the shape of the heat dissipation plate 10 is cylindrical in this embodiment, it can be produced in various forms such as square or polygon.

As the electrical insulating film 12, a white resin film and a photosensitive resin film which can be selectively removed by exposure and development by photolithography technology are used. Alternatively, the electrical insulation film 12 may be formed of a nitride film or an oxide film grown on a metal plate. In this embodiment, a photosensitive resin film was used in consideration of heat dissipation performance and productivity. In the present embodiment, the electrical insulation film 12 is formed only on the upper surface of the heat dissipation plate 50, but may be formed on the sidewall of the heat dissipation plate 12 as necessary and according to the manufacturing method.

Meanwhile, in the present embodiment, the case in which the electric insulation film 12 is removed from the chip bonding regions 12a will be described. However, if necessary, the electric insulation film 12 may be formed on the entire upper surface of the heat radiating plate 10. have. Although the electrical insulation film 12 is formed on the front surface of the heat dissipation plate 10, although it is somewhat disadvantageous in terms of heat dissipation effect, it is advantageous in that the heat dissipation plate 10 can be simply manufactured. In particular, when the nitride film having a low thermal resistance is used as the electrical insulating film 12, a silver or white light reflecting film having good light reflection efficiency is further formed on the electrically insulating film which is not removed in the chip bonding region 12a. Can be formed.

On the other hand, in order to prepare the heat dissipation plate 10 as shown in Figure 1, as a material of the heat dissipation plate before being cut into one unit heat dissipation plate 10, a plate having a good thermal conductivity as a panel form having a large area Is prepared, and the electrical insulation film 12 of various materials as described above is formed on the upper surface thereof. In this embodiment, a photosensitive resin is used.

Subsequently, a part of the electrical insulation film 12 at the position where the chip bonding region 12a is formed is removed. When the electrical insulation film 12 is a photosensitive resin film, a part of the electrical insulation film 12 may be selectively removed by performing exposure, development, and washing processes using photolithography techniques commonly used in semiconductor manufacturing processes. Subsequently, before cutting the heat dissipation plate into individual unit heat dissipation plates 10, a method of drilling fixing grooves (not shown) for fixing the heat dissipation plate 10 in place in the lower mold during the plastic molding process is performed. The heat-dissipating plate sheet is cut into individual unit heat-dissipating plates 10 by punching or cutting.

On the other hand, if necessary, the electrical insulation film 12 may not be removed, and when removing a portion of the electrical insulation film 12, the electrical insulation film 12 and a portion of the upper surface of the heat dissipation plate are removed together so that the heat dissipation plate 10 may be removed. A recess region may be formed in the chip bonding region 12a of the. Also, if necessary, a plating layer, for example, silver, is formed only on the entire surface of the upper surface of the heat dissipating plate 10 or in the chip bonding region 12a from which the electric insulating film 12 is removed. You may further form a plating layer.

On the other hand, only in the case of applying the photosensitive resin as the electrical insulating film 12, in accordance with the shape of the heat emitting plate to form the shape of the individual heat emitting plate in the forging or punching method, and then can be used to select the method of forming the electrical insulating film. have. When the heat dissipation plate is circular and the diameter is relatively small, the heat dissipation plate is formed in the shape of the heat dissipation plate by using a metal material in the form of a wire, and then the individual heat dissipation plates are almost spaced apart to form an electric insulation film on the upper surface of each heat dissipation plate. Insert into a subplate with aligned holes or grooves that can be secured or held. Such an auxiliary plate is prepared such that when the heat radiating plate is inserted, the upper surface of the heat radiating plate and the upper surface of the auxiliary plate are almost at the same level. Subsequently, a photosensitive resin film was attached over the entire upper surface of the auxiliary plate aligned with the upper surface of the heat radiating plate, and an electrical insulating film 12 was formed by forming an electrical insulating film only on the upper surface of the heat radiating plate using photolithography technology or the like and separating it from the auxiliary plate. The heat radiating plate 10 can be completed.

As another method, in the case of a circular or non-circular shape having a relatively large diameter, the metal plate is press-punched into a heat-dissipating plate shape, but rewound in a state in which it is not completely eliminated, so that the heat-dissipating plate is formed. Have the same front as prepared. Subsequently, the photosensitive resin film may be attached over the entire surface of the plate, and an electrical insulating film may be formed only on the upper surface of the heat radiating plate by using photolithography technology, or the like.

2 is a view showing a lead frame used to manufacture a multi-chip light emitting diode package according to a first embodiment of the present invention.

Referring to FIG. 2, the lead frame 20 is formed of a conductive metal material, and a pair of inner lead wire ends 24c and 26c border the shape of a taegeuk, corresponding to the upper surface shape of the heat dissipation plate 10 of FIG. 1. It is composed of a broadly extended form facing each other. More specifically, the first lead wire 24a and the second lead wire 24b are connected to the first inner lead wire end 24c, and the third lead wire 26a and the fourth lead wire ( 26b) is connected. In addition, the first lead wire 24a and the third lead wire 26a are connected to the lead frame 20 and the first side rail 22a, and the second lead wire 24b and the fourth lead wire 26b are the second side rails. It is connected to 22b.

On the other hand, the inner lead wire ends 24c and 26c having a wide extension to correspond to the shape of the upper surface of the heat dissipation plate 10 having the electrical insulation film 12 formed thereon may maximize the area overlapping with the heat dissipation plate 10. To maximize the heat dissipation effect through the (24a, 24b, 26a, 26b). The pair of inner lead wire ends 24c and 26c facing each other constitute a plurality of spaces 28 defining a plurality of chip bonding regions 12a along its boundary. In addition, as shown in FIG. 4C, the bent portion 25 is formed in the middle of the lead wires so as to be spaced apart from the upper surface of the heat radiating plate 10. The bent portion 25 is formed near the edge of the heat dissipation plate 10, and the lead wires are exposed when the surface of the heat dissipation plate 10 is exposed because the electric insulation film 12 is damaged or deformed near the edge of the heat dissipation plate 10. The purpose of this is to prevent direct contact between the 24a, 24b, 26a, 26b and the heat dissipation plate 10 to cause a short circuit.

In general, the lead frame 20 is manufactured by a method of punching or etching a relatively thin metal plate, and a plurality of lead wires become electrical wires of the package, and the lead wires form the plastic molded body 30 of the package as shown in FIG. 5C. The inner lead wire and the outer lead wire are separated into boundaries, and the ends 24c and 26c of the inner lead wires provide a wire bonding area for electrical connection with the LED chips, and the outer lead wires are electrically connected to the printed circuit board mounting the package. It is provided as an external terminal for On the other hand, in the lead frame 20 of the present invention, a plating layer may be lead in the wire bonding region to which at least the bonding wire is bonded.

On the other hand, in the package according to the present invention it may be used to include only one lead wire as another alternative to the lead frame. That is, for example, when the light emitting diode chip is a vertical chip, one lead wire (or a plurality of lead wires may be used) is used as one electrode of the chip, and a heat radiating plate may be used as another electrode.

FIG. 3A is a plan view showing an arrangement relationship between the heat dissipation plate of FIG. 1A and the lead frame of FIG. 2, FIG. 3B is a cross-sectional view taken along line 3B-3B 'of FIG. 3A, and FIG. 3C is a line 3C-3C' of FIG. 3A. It is a cut section. That is, the centers of the inner lead wire ends 24c and 26c are disposed to correspond to the center of the upper surface of the heat radiating plate 10, and each chip bonding area 12a is formed in each space 28 of the lead frame 20. To be deployed.

4A to 4C, a molding process is performed to fix the heat dissipation plate 10 and the lead frame 20 with the plastic molding body 30 to complete the LED package base. The plastic molding body 30 may be a mold molding material, and may use a white thermosetting or thermoplastic resin having a high light reflectivity as much as possible. As described above, in the present embodiment, the plastic molding body 30 has an outer wall almost vertical, but on the inner side, the wire bonding regions 12a of the heat dissipation plate 10 and the inner lead wire ends 24c and 26c. A cavity is provided that exposes 27 and forms an interior space throughout the package. This is to facilitate the application of the phosphor or the formation of the lens portion in the subsequent manufacture of the LED package, and at the same time to improve the luminous efficiency from the LED chip. Reference numeral 32 denotes a part of the plastic molding body formed on the sidewalls of the inner lead wire ends 24c and 26c exposed toward the chip bonding region 12a, which may not be formed.

5A to 5C, after bonding the LED chips 40 to the respective chip bonding regions 12a, bonding pads (not shown) formed on the top surface of the LED chips 40 may be used. Bonding wires 32 connect the wire bonding regions 27 exposed at the inner lead wire ends 24c and 26c. The LED chips 40 used in the present embodiment may all emit light of the same color, and may be configured to emit light of various colors as necessary. In addition, red light, green light and blue light may be disposed at an appropriate ratio to emit white light.

FIG. 6 is a cross-sectional view showing an example of a package in which the hemispherical lens unit 50 is separately formed on each light emitting diode chip of FIG. 5C. Phosphors (not shown) are formed in the cavity on each light emitting diode chip 40 positioned below the lens unit 50. In the finished package, a part of the external lead wire is bent to be easily attached to a printed circuit board or the like. FIG. 7 is a cross-sectional view illustrating an example of a package in which one hemispherical lens unit 52 is formed on the entire light emitting diode chip of FIG. 5C.

FIG. 8 is a cross-sectional view showing an example of a package in which the crown lens portion 54 is formed on the entire light emitting diode chip corresponding to FIG. Specifically, the conical cone is recessed in the center of the upper end of the lens unit 54, and the mirror coating 54a is provided along the upper end surface. This is to induce side emitting by applying a mirror coating 54a to the irradiated surface to which light emitted upward from each of the LED chips 40 is applied. In order to improve the quality of the light emitted from the light emitting diode illumination device having a parabolic reflector, this is to cover or disperse the hot spot of the light emitting diode chip close to the point light source and to indirectly increase the amount of light reflected by the parabolic reflector. As in the lens section 54, mirrors are formed on the shape of the inverted cone cone of the lens for full side emission while increasing the light efficiency according to the depth or angle of the inverted cone cone penetrating downward from the upper center of the lens unit 54. Coating 54a.

As described above, in order to manufacture a multi-chip LED package according to the present invention, a step of preparing a heat dissipation plate having an electrical insulation film exposed a plurality of chip bonding regions on the upper surface, overlapping the heat dissipation plate and the light emitting diode Preparing a lead frame having an internal lead wire to provide a wire bonding area for wire bonding with a chip, and exposing each chip bonding area and wire bonding area and forming a cavity-shaped light reflecting cup to form an internal lead wire and heat radiation. Forming a plastic molded body that presses the publication, the wire bonding step.

Second Embodiment

12A to 15C are plan views and cross-sectional views illustrating a process of manufacturing a multi-chip LED package according to a second embodiment of the present invention. The same components as in the first embodiment use the same reference numerals as those used in the drawings for describing the first embodiment, and detailed description of the same components is omitted. The second embodiment is distinguished from the first embodiment in that the through hole 14 is formed in the center of the heat radiating plate 10 '.

12A is a plan view of a heat dissipation plate for manufacturing a multi-chip LED package according to a second embodiment of the present invention, and FIG. 12B is a cross-sectional view taken along line 1B-1B ′ of FIG. 11A.

12A and 12B, the heat dissipation plate 10 ′ has a cylindrical shape having a through hole 14 in the center thereof, and an electric insulation film 12 is formed on the heat dissipation plate 10 ′. The portion of the electrical insulation film 12 removed is the chip bonding region 12a.

FIG. 13A is a plan view showing an arrangement relationship between the heat dissipation plate 10 'and the lead frame 20' of FIG. 12A, FIG. 13B is a cross-sectional view taken along line 13B-13B 'of FIG. 13A, and FIG. 13C is 13C of FIG. 13A. Section taken along line -13C '. The lead frame used in this embodiment is a lead frame very similar to the lead frame 20 of FIG. 2, and the second space portion 29 is formed so as to correspond to the through hole 14 formed in the center of the heat radiating plate 10 '. Same as the leadframe of FIG. 2 except that it is configured to be provided.

FIG. 14A is a plan view showing a package base in which the heat dissipation plate 10 'and the lead frame 20' are integrated into a plastic molded body, and FIG. 14B is a cross-sectional view taken along the line 14B-14B 'of FIG. 14A, and FIG. It is sectional drawing which cut 14C-14C 'of 14a.

14A to 14C, a molding process is performed to fix the heat radiating plate 10 ′ and the lead frame 20 ′ with the plastic molding body 30 to complete the light emitting diode package base. The plastic molding body 30 is different in that it is not formed near the through hole 14 formed in the center of the heat radiating plate 10 'as compared with the first embodiment. In addition, the plastic molding body 30 is formed to expose the electrical insulation film 12 around the through hole 14, but may be formed to cover the inner wall of the through hole 14 as necessary.

15A to 15C, after bonding the LED chips 40 to the respective chip bonding regions 12a, bonding pads (not shown) formed on the top surface of the LED chips 40 may be used. Bonding wires 32 connect the wire bonding regions 27 exposed at the inner lead wire ends 24c and 26c.

Subsequently, as in the package according to the first embodiment, the hemispherical lens portion 50 may be formed on each LED chip individually, or one hemispherical lens portion 52 may be formed on the entire LED chip. As shown in FIG. 8, the crown lens portion 54 may be formed on the entire LED chip.

Third Embodiment

The third embodiment relates to an example of a light emitting diode package configured to emit white light for use as a backlight of a display device. That is, the red light emitting diode chip, the green light emitting diode chip and the blue light emitting diode chip are arranged in an appropriate number in one package, and the red light, the green light, and the blue light emitted from these chips are appropriately mixed to produce white light.

In general, a light emitting diode chip emitting green light requires more light than other wavelengths in order to realize white light by mixing color, and therefore, it is preferable to supply more current than other chips. In light of the reduction, it is desirable to place the green light emitting diode chip in a larger or larger number in order to equalize life with other chips.

For example, on the backlight unit, the ratio of the light intensity of the red / green / blue light emitting diode chip to achieve the target specific color coordinates x = 0.28, y = 0.28 (based on CIE colorimeter, 1976) is 5.5: 14: 1. The number of light emitting diode chips can be selected and arranged so that a ratio of red light (R): green light (G): blue light (B) = 1: 2: 1 can be arranged in one package in consideration of the sum of colors for white light. . Meanwhile, the green light chips can be connected in series and in parallel.

On the other hand, in the present invention, the light emitting diode chip has a horizontal type in which both electrodes of the anode and the cathode are placed on one plane on the non-conductive substrate according to the arrangement of the electrodes, and two wire bondings are required, and the electrodes are placed on and under the conductive substrate. It can be divided and applied to all vertical types requiring at least one wire bonding on the top surface. In the case of the horizontal type, six lead wires of a cathode and an anode may be wire-bonded to the red light chip, the green light chips, and the blue light chip. In the case of the vertical type, the conductive substrate (heat radiating plate of the present embodiment) may be one of a cathode or an anode, and one lead wire may be wire-bonded to each of red light, green light, and blue light.

In the following embodiment, one red light chip, two green light chips, and one blue light chip are disposed, and the two green light chips are connected to each other in parallel, and are described based on six terminals having six lead wires.

FIG. 16A is a plan view of a heat dissipation plate for fabricating a multi-chip LED package in which RGB three-way light is emitted into one package and emitting white light according to a third embodiment of the present invention, and FIG. This is a cross-sectional view taken along line 16B '. Detailed description of the similar components as in the above-described first and second embodiments will be omitted.

16A and 16B, an electrical insulation film 112 is formed on the heat dissipation plate 110. A portion of the electrically insulating film 112 is removed to form the chip bonding region 112a. In the present embodiment, a plurality of, for example, four are disposed based on the center of the heat radiating plate 110.

The heat dissipation plate 110 may be a metal plate such as copper (Cu) or aluminum (Al) having a good thermal conductivity, in addition to the metal or alloys such as Ag, Mo, Fe, Ni, W may be used, Furthermore, a ceramic material having excellent thermal conductivity may be used. As described above, the heat dissipation plate 110 may be non-conductive in the case where the arrangement of the light emitting diode chip is horizontal. However, the heat dissipation plate 110 should be electrically conductive. Although the heat radiating plate 110 has a rectangular shape, it may be manufactured in various forms such as a circle or a polygon as necessary.

FIG. 17 illustrates a leadframe 120 used to manufacture a multi-chip light emitting diode package according to a third embodiment of the present invention.

Referring to FIG. 17, the lead frame 120 is formed of a conductive metal material and has four spaces so as to expose four chip bonding regions 112a corresponding to the top surface shape of the heat dissipation plate 110 of FIG. 16. The portion 128 is shaped to be formed. More specifically, the first to third lead wires 124a, 124b, and 124c are connected to the first side rails 122a of the lead frame 120, respectively, and the ends of the first to third internal lead wires 124 at the ends thereof. 'a, 124'b, and 124'c are connected by the bent portions 125, respectively. Fourth to sixth lead wires 126a, 126b, and 126c are connected to the second side rails 122b of the lead frame 120, respectively, and end portions of the fourth to sixth internal lead wires 126'a and 126 are respectively connected to ends of the lead frame 120. FIG. 'b, 126'c are connected by the bent portions 125, respectively.

In Fig. 17, the space 128 surrounded by the first inner lead end 124'a, the fourth inner lead end 126'a, and the fifth inner lead end 126'b is formed of a red light emitting diode chip. Two spaces 128 corresponding to the first chip bonding region to be bonded and surrounded by the second inner lead end 124'b and the fifth inner lead end 126'b are bonded to the green light emitting diode chip. A space portion corresponding to the second and third chip bonding regions and surrounded by the third inner lead line end 124'c, the second inner lead line end 124'a, and the sixth inner lead line end 126'c; 128 corresponds to the fourth chip bonding region to which the blue light emitting diode chip is bonded.

FIG. 18A is a plan view showing an arrangement relationship between the heat dissipation plate of FIG. 16A and the lead frame of FIG. 17, and FIG. 18B is a cross-sectional view taken along the line 18B-18B 'of FIG. 18A. Each chip bonding region 112a is disposed in each space portion 128 of the lead frame 120.

FIG. 19A is a plan view showing a package base in which the heat dissipation plate of FIG. 16A and the lead frame 120 of FIG. 17 are integrated with a plastic molded body 130, and FIG. 19B is a cross-sectional view taken along the line 19B-19B 'of FIG. 19A. .

19A and 19B, a molding process may be performed to fix the heat dissipation plate 110 and the lead frame 120 with the plastic molding body 130 to complete the LED package base. In the present embodiment, the plastic molding body 130 has an outer wall almost vertical, but inside the four chip bonding regions 112a of the heat dissipation plate 110 and the wire bonding regions 127 at the ends of the inner lead wires. A cavity is provided that forms an interior space throughout the package. Reference numeral 132 denotes a partially formed plastic molding body formed on the sidewall of each end of the inner lead wire exposed toward the chip bonding region 112a, which may not be formed.

Referring to FIGS. 20A and 20B, after bonding the LED chips 140 to each chip bonding region 112a, bonding pads (not shown) formed on the top surface of the LED chips 140 may be used. The bonding wire 132 is connected between the wire bonding regions 127 exposed at the ends of the inner lead wires. In the present embodiment, a red light emitting diode chip is bonded to the first chip bonding region, a green light emitting diode chip is bonded to the second and third chip bonding regions connected in parallel, and a blue light emitting diode chip is bonded to the fourth chip bonding region. .

FIG. 21 is a cross-sectional view showing an example of a package in which one hemispherical lens unit 152 is formed over each light emitting diode chip of FIG. Phosphors (not shown) are formed in the cavity on each LED chip 140 positioned below the lens unit 152. In the finished package, a part of the external lead wire is bent to be easily attached to a printed circuit board or the like. On the other hand, a separate hemispherical lens portion may be configured independently on each light emitting diode chip, and as shown in FIG. 8, a crown lens portion may be formed on the entire light emitting diode chip for side light emission.

Fourth Embodiment

The fourth embodiment relates to a light emitting diode lighting apparatus in which a light emitting diode package manufactured according to the first to third embodiments described above is mounted in a cup-shaped reflector.

Hereinafter, although the side light emitting diode package of FIG. 8 is described as an example, all light emitting diode packages according to the present invention may be used.

First, as can be seen in Figure 9, the package according to the present invention is mounted on the printed circuit board 56 in the forward direction so that the light emitted from the light emitting diode chip toward the opening of the reflector 60. The bonding pads 55 and the lead wires 26b formed on the printed circuit board 56 are electrically connected to each other. The package mounted on the printed circuit board is installed below the inner surface of the cup-shaped reflector 60.

10 shows an example in which the lens 54 of the package is configured in the reverse direction to face the bottom of the reflector 62. In this case, as in the second embodiment, a through hole 14 is formed in the center of the heat radiating plate 10 '. The center of the lens unit 54 and the printed circuit board 56a also penetrates corresponding to the through hole 14, and a through hole 62a is formed at the bottom of the bottom surface of the reflector 62. In order to secure the distance between the inner surface of the reflector 62 and the package, a pipe 62b is provided which can be fixed while communicating between the through hole 62a of the reflector 62 and the through holes of the package. Solder balls 57 are formed on the rear surface of the printed circuit board 56a to be connected to the external terminal lines 58a and 58b, and the external terminal lines are connected to the outside of the lighting device through the pipe 62b.

FIG. 11 is a modified example of FIG. 10, in which the shape of the reflector 64 is changed, and as shown, a double bottom is formed below the inner surface to increase light dispersion efficiency.

The above embodiments are merely exemplary, and various modifications and equivalent other embodiments are possible to those skilled in the art. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the invention described in the claims below.

As described above, according to the present invention, by configuring a plurality of light emitting diode chips in one package, the light output can be extremely increased.

In addition, according to the present invention, while increasing the volume of the heat dissipation plate within a limited package volume, the overlapping area with the lead wires was increased to improve the performance of heat dissipation through the heat dissipation plate and the lead wires.

In addition, according to the present invention, the three-way light is configured in one package to effectively emit white light, which can be usefully used as a backlight of a display device.

In addition, according to the present invention, it is possible to vary the light-directed pattern by variously configuring the lens portion of the package, it is possible to uniformly achieve light dispersion by varying the mounting and reflector of the package.

Claims

A heat dissipation plate providing a plurality of chip bonding regions on an upper surface thereof and dissipating heat generated from the light emitting diode chip mounted on the chip bonding region;

An electrical insulation film formed on the heat dissipation plate while exposing the chip bonding regions;

A lead frame in direct contact with and overlapping with the heat dissipation plate via the electrical insulation film, the lead frame including at least one internal lead wire having a terminal end adjacent to each of the chip bonding regions;

The tip of the inner lead wire is fixed to the upper surface of the heat dissipation plate in close contact with each other, and the chip is exposed while exposing the plurality of wire bonding areas and the chip bonding areas formed at the ends of the inner lead wire in correspondence to the respective chip bonding areas. A plastic molded body shaped to form a cavity over the bonding regions;

A plurality of light emitting diode chips mounted in each of the chip bonding regions;

A plurality of bonding wires electrically connecting the respective LED chips and the wire bonding regions corresponding thereto; And

A lens unit disposed on the light emitting diode chips;

Multi-chip LED package comprising a.

The multi-chip LED package of claim 1, wherein the heat dissipation plate has a through hole formed in a central portion thereof.

The multi-chip LED package of claim 1, wherein the chip bonding regions are arranged concentrically on an upper surface of the heat dissipation plate.

The method of claim 1, wherein the lead frame comprises at least one pair of inner lead wires facing each other while defining the respective chip bonding regions, and at least one inner lead wire connected to each of the inner lead wire ends. -Chip light emitting diode package.

The multi-chip LED package of claim 1, wherein the lens unit is a multiple lens unit independently formed for each LED chip, or a single lens unit formed on each LED chip.

The multi-chip LED package of claim 1, wherein the lens unit is a side-emitting type lens unit that emits light emitted from each LED chip in a lateral direction.

The multi-chip LED package of claim 1, wherein the electrical insulation layer is removed or not removed in the chip bonding region.

The multi-chip LED package of claim 1, wherein the inner lead line is bent to be spaced apart from the heat radiating plate near an edge of the heat radiating plate.

The multi-chip LED package according to claim 1, wherein the chip bonding regions are arranged with LED chips emitting light of the same color.

The multi-chip LED package of claim 1, wherein each of the chip bonding regions comprises at least one LED chip emitting red light, green light, and blue light.

The method of claim 1,

The chip bonding regions may include a first bonding region in which a red light emitting diode chip is mounted, a second bonding region in which a green light emitting diode chip is mounted, a third bonding region, and a fourth bonding region in which a blue light emitting diode chip is mounted. Multi-chip LED package.

The method of claim 11,

The red light emitting diode chip, the green light emitting diode chip and the blue light emitting diode chip are each electrically connected to at least one internal lead wire.

The method of claim 11,

The red and blue light emitting diode chips are connected to a pair of internal lead wires, respectively, and the green light emitting diode chips are connected to a pair of internal lead wires in parallel.

A printed circuit board having a bonding pad formed on an upper surface thereof;

A multi-chip light emitting diode package mounted on the printed circuit board; And

And a cylindrical groove reflector for mounting the printed circuit board on which the multi-chip LED package is mounted.

The light emitting diode package,

The heat dissipation layer is directly in contact with and overlaps with the heat dissipation layer, and the terminal extends from at least one inner lead line and the inner lead line which are commonly adjacent to the respective chip bonding regions, and is connected to the bonding pad of the printed circuit board. A lead frame including external lead wires;

A lens unit disposed on the light emitting diode chips;

LED lighting apparatus comprising a.

The method of claim 14,

The reflector is a semi-spherical inner surface, the light emitting diode illumination device, characterized in that the bottom of the printed circuit board is mounted on the center of the bottom inner surface of the reflector.

The method of claim 15,

The lens unit is a light emitting diode illumination device, characterized in that the side emitting type lens unit for causing the light emitted from each of the LED chip to be irradiated in the lateral direction.

The method of claim 14,

And a lens unit of the light emitting diode package facing the lower surface of the reflector.

The method of claim 17,

Through holes are formed in the center of the reflector, the light emitting diode package and the printed circuit board, respectively.

A pipe disposed therebetween so as to communicate the through holes, and the reflector and the LED package maintain a constant distance; And

And an external terminal wire connected to the lower surface of the printed circuit board through the pipe.

15. The LED lighting apparatus of claim 14, wherein LED chip emitting light of the same color is arranged in the chip bonding regions.

15. The LED lighting apparatus of claim 14, wherein each of the chip bonding regions includes at least one LED chip emitting red light, green light, and blue light.

The method of claim 20,

The chip bonding regions may include a first bonding region in which a red light emitting diode chip is mounted, a second bonding region in which a green light emitting diode chip is mounted, a third bonding region, and a fourth bonding region in which a blue light emitting diode chip is mounted. LED lighting device.