TW201304217A - LED package and method for manufacturing the same - Google Patents

Abstract

An LED package includes a number of electrodes, a plurality of LED chips electrically connected to the electrodes and an encapsulation covering the LED chips. The electrodes include a plurality of metal layers separated from each other. A plurality of grooves corresponding to the LED chips is defined in one surface of the encapsulation which is attached to the electrodes. The LED chips are received in the grooves respectively and connected with the electrodes through electrode pads thereof. A reflecting portion surrounds a portion of an outside of the encapsulation which is adjacent to the electrodes. The present invention also provides a method for manufacturing the LED package.

Description

Light-emitting diode package structure and manufacturing method thereof

The present invention relates to a semiconductor structure, and more particularly to a light emitting diode package structure and a method of fabricating the same.

Compared with the traditional illumination source, the Light Emitting Diode (LED) has the advantages of light weight, small volume, low pollution and long life. It has been widely used as a new type of illumination source. .

A conventional LED package structure generally includes a substrate, an electrode formed on the substrate, and a light emitting diode chip mounted on the substrate and electrically connected to the electrode. The connection mode of the LED body and the electrode is usually completed by a solid crystal wire bonding method. However, the solid crystal wire bonding process is not only complicated and cumbersome, but also easy to cause the wire to fall off due to human error, thereby affecting the manufacturing yield of the LED package structure. Moreover, the heat dissipation problem of the LED package structure has been a topic that the industry has been trying to explore.

In view of the above, it is necessary to provide a light emitting diode package structure which is simple to manufacture and which is advantageous for heat dissipation, and a manufacturing method thereof.

A light emitting diode package structure comprising an electrode, a plurality of light emitting diodes electrically connected to the electrode, and a package covering the light emitting diode, wherein the electrode comprises a plurality of metal layers spaced apart from each other, the package body a surface adjacent to the electrode is provided with a groove corresponding to the light emitting diode, and the light emitting diode is received in the groove and connected to the electrode by an electrode pad, and the package body is disposed adjacent to a peripheral portion of the electrode There is a reflection section.

A method for manufacturing a light emitting diode package structure, comprising the steps of:

Providing a transparent carrier plate, one of the surfaces of the carrier plate is recessed inwardly to form a plurality of grooves, and the carrier plate is made of a transparent material;

a light emitting diode is disposed in the recess of the carrier, the light emitting diode includes a light emitting diode wafer and an electrode pad, and the electrode pad is disposed toward the opening direction of the groove;

Providing a concave plate, the concave plate comprising a plurality of separate metal layers and a reflection portion disposed on a periphery of the metal layer;

The concave plate is disposed on the carrier, and the electrode pads of the LED chip are electrically connected to the metal layer, and the reflection portion is disposed on the outer surface of the carrier.

Since the light-emitting diode is directly electrically connected to the metal layer, the process steps such as solid-crystal bonding for fixing and electrically connecting the light-emitting diode wafer are omitted, the manufacturing process is more simple, and the light-emitting diode is directly The contact with the metal layer is connected, so that the heat generated by the light-emitting diode can be directly conducted downward through the metal layer to the outside of the light-emitting diode package structure, which is favorable for heat dissipation.

The invention will now be further described with reference to the specific embodiments thereof with reference to the accompanying drawings.

Referring to FIG. 1 , a light emitting diode package structure 100 according to a first embodiment of the present invention includes a substrate 10 , an electrode 20 , a light emitting diode 30 fixed on the electrode 20 and electrically connected to the electrode 20 , and a cover light. The package body 40 of the diode 30 and the reflection portion 50.

The substrate 10 has a substantially rectangular flat shape, and the substrate 10 includes an upper surface 11, a lower surface 12 opposite to the upper surface 11, and a plurality of side surfaces 13 connecting the upper surface 11 and the lower surface 12. At least two through holes 14 are defined in the substrate 10 . In the present embodiment, the through holes 14 are two, and the through holes 14 are respectively adjacent to opposite side faces 13 of the substrate 10 , and each of the through holes 14 extends from the upper surface 11 to the lower surface 12 . The through hole 14 is for receiving the electrode 20 . The upper surface 11 and the lower surface 12 are both planar, and the upper surface 11 is for carrying the light emitting diode 30. The material of the substrate 10 may be a material having a high reflectance such as ceramic, tantalum or the like.

The electrode 20 is formed on the substrate 10. The electrode 20 includes a first electrode 21, a second electrode 22, and a plurality of metal layers 23 between the first electrode 21 and the second electrode 22. The first electrode 21, the metal layer 23 and the second electrode 22 are spaced apart from each other. The first electrode 21 is filled in one of the through holes 14 of the substrate 10. The bottom surface of the first electrode 21 is flush with the lower surface 12 of the substrate 10, and the top surface is higher than the upper surface 11 of the substrate 10. The second electrode 22 is filled in the other through hole 14 of the substrate 10. The bottom surface of the second electrode 22 is flush with the lower surface 12 of the substrate 10, and the top surface is higher than the upper surface 11 of the substrate 10. The bottom surfaces of the first electrode 21 and the second electrode 22 are both exposed in the through holes 14 of the substrate 10 for connecting with external circuits to supply electric power to the LED package structure 100. The metal layer 23 is laid on a portion of the upper surface 11 of the substrate 10 between the first electrode 21 and the second electrode 22. The thickness of the metal layer 23 is substantially equal to the height of the portion of the first electrode 21 and the second electrode 22 that is higher than the upper surface 11 of the substrate 10. In specific implementation, the number of the metal layers 23 varies depending on the number of the light emitting diodes 30. In the present embodiment, the number of the metal layers 23 is two, and the two metal layers 23 are spaced apart from each other and electrically different for electrically connecting the three light emitting diodes 30.

The light emitting diode 30 is mounted on the substrate 10 . Specifically, each of the light emitting diodes 30 includes a light emitting diode chip 31 and an electrode pad 32. The LED chip 31 includes a light emitting surface 311 and a backlight surface 312. The electrode pads 32 are at least two and disposed on the backlight surface 312. In a specific implementation, the number of the LEDs 30 may be one or plural according to different requirements. In the present embodiment, the number of the light emitting diodes 30 is three, which are the first light emitting diode 30a, the second light emitting diode 30b, and the third light emitting diode 30c, respectively. The three LEDs 30 are arranged in a row on the substrate 10, and the two electrode pads 32 of each of the LEDs 30 are respectively connected to the adjacent two electrodes 20. Specifically, the two electrode pads 32 of the first light emitting diode 30a are respectively connected to the first electrode 21 and the metal layer 23 adjacent to the first electrode 21 . The two electrode pads 32 of the third light emitting diode 30c are respectively connected to the second electrode 22 and another metal layer 23 adjacent to the second electrode 22. One of the electrode pads 32 of the second light-emitting diode 30b and the first light-emitting diode 30a are connected to the same metal layer 23, and the other electrode pad 32 and the second light-emitting diode 30b are connected to the same metal layer 23. In other embodiments, an anisotropic conductive paste or a silver paste may be disposed between the electrode pad 32 and the electrode 20 of the light-emitting diode 30 to increase the buffer between the light-emitting diode 30 and the electrode 20, and also Connection strength and conductivity can be increased.

The package body 40 is covered on the substrate 10 and integrally formed of a transparent material, such as glass. The package body 40 includes a light-emitting surface 41 away from the substrate 10, a bonding surface 42 that is bonded to the substrate 10, and an outer surface 43 that connects the light-emitting surface 41 and the bonding surface 42. A plurality of recesses 44 are formed in the joint surface 42. The recesses 44 are recessed from the joint surface 42 toward the light exiting surface 41. Each of the recesses 44 receives a light emitting diode 30 therein. In the present embodiment, the depth of the groove 44 is substantially equal to the sum of the thicknesses of the LED wafer 31 and the electrode pad 32, and the length and width of the groove 44 are respectively different from the length and width of the LED wafer 31. When the LEDs 31 are received in the corresponding recesses 44, the top surface and the side surfaces of the LEDs 31 can be in contact with the inner surface of the package 40 forming the recesses 44, thereby facilitating the illumination. The heat generated by the polar body 30 is transferred to the package body 40 to be radiated outward. The outer side surface 43 of the package body 40 is flush with the side surface 13 of the substrate 10 to form a vertical side plane.

The reflecting portion 50 surrounds a bottom end portion of a side plane of the light emitting diode package structure 100. Specifically, the reflection portion 50 is annularly provided on the side surface 13 of the substrate 10 and the outer surface 43 of the package 40 at a portion close to the substrate 10 . The bottom end of the reflecting portion 50 is flush with the lower surface 12 of the substrate 10, and the top end is higher than the top surface of the light emitting diode 30. With this configuration, a part of the light emitted from the light-emitting diode 30 is directly emitted from the light-emitting surface 41 of the package 40, and the other portion is incident on the reflection portion 50, reflected by the reflection portion 50, and finally emitted from the light-emitting surface 41. The reflective portion 50 can be made of a material having a high reflectivity. In a specific implementation, the material of the reflective portion 50 can be the same as that of the substrate 10 and both are made of a high reflectivity material, so that the reflective portion 50 and the substrate 10 can be The substrate 10 and the reflection portion 50 are simultaneously formed by using a mold having a concave accommodating space, and the reflection portion 50 is located at both ends of the substrate 10, thereby making the substrate 10 The reflection portion 50 is integrally formed with a "concave" shape.

In other embodiments, a phosphor layer (not shown) may be coated on the light-emitting surface 41 of the package 40 and another portion of the outer surface 43 of the package 40 that is not covered by the reflective portion 50, thereby changing the light-emitting diode. The body 30 emits optical properties of light.

In the embodiment, the LEDs 30 are directly connected to the electrodes 20 by the electrode pads 32, which not only avoids the cumbersome and difficult manufacturing process caused by the wire bonding process, but also avoids the use of the LED package structure. There are hidden dangers such as detachment and breakage of the wires. The light-emitting diode 30 is directly in contact with the electrode 20, and the bottom end of the electrode 20 is directly exposed on the lower surface 12 of the substrate 10, so that the heat generated by the light-emitting diode 30 can be directly transmitted downward through the electrode 20 to the light-emitting diode 2 In addition to the polar package structure 100, the heat dissipation performance of the light emitting diode package structure 100 is increased. In addition, the package body 40 is integrally formed with a glass material and covers the light-emitting diode 30, thereby avoiding problems such as yellowing and chipping of the encapsulation layer caused by the heat generated by the light-emitting diode 30 in the prior art. It is also possible to allow another portion of the heat generated by the LEDs 30 to be conducted upward through the package 40 to the outside of the LED package structure 100 for higher heat dissipation efficiency. In addition, an electrode 20 for electrically connecting the light-emitting diodes 30 is formed on the upper surface 11 of the substrate 10, the electrode 20 can function as a reflective layer, and the reflective portion 50 surrounds the side of the substrate 10. 13 and a bottom end portion of the outer side surface 43 of the package 40 and the side surface 13 of the substrate 10, the metal layer 23 and the reflecting portion 50 together form a substantially U-shaped reflecting surface, thereby emitting the light emitting diode 30 The light is effectively reflected to be emitted from the light exit surface 41 of the package body 40 to enhance the light extraction efficiency of the light emitting diode package structure 100.

Referring to FIG. 2 , a light emitting diode package structure 200 according to a second embodiment of the present invention is different from the light emitting diode package structure 100 of the first embodiment in that the substrate 10 a includes a plurality of separate structures. The metal layer 23a and a plurality of insulating blocks 24a connecting between the adjacent two metal layers 23a. The thickness of the metal layer 23a is substantially equal to the thickness of the substrate 10, and the adjacent two metal layers 23a are electrically insulated by an insulating block 24a. Each of the light emitting diodes 30 respectively connects the adjacent two metal layers 23a. Specifically, the two electrode pads 32 of each of the light-emitting diodes 30 are respectively connected to the adjacent two metal layers 23a. The LED package structure 200 of the present embodiment directly uses the metal layer 23a as a substrate, because the metal layer 23a is made of a metal material, has high thermal conductivity and high reflection performance, and generates heat generated by the LEDs 30. Conducting downwardly through the metal layer 23a to the outside of the light emitting diode package structure 200, thereby improving heat dissipation efficiency; the reflection portion 50 is annularly disposed on the side surface of the substrate 10a and the outer side surface of the package body 40, and thus the metal layer 23a and the reflection The portions 50 collectively form a substantially U-shaped reflective surface surrounding the LEDs 30, thereby effectively reflecting the light emitted by the LEDs 30 from the light-emitting surface 41 of the package 40 to enhance the illumination. The light extraction efficiency of the polar package structure 100. In addition, a phosphor layer 80 is formed on the outer surface of the package 40.

Referring to FIG. 3, a light emitting diode package structure 300 according to a third embodiment of the present invention is different from the light emitting diode package structure 100 of the first embodiment in that the substrate 10b has a "concave" shape. It is made of a transparent material. The substrate 10b includes a horizontal flat portion 11b and a vertical portion 12b located at the periphery of the flat portion 11b. Of course, the substrate 10b may also be a plate structure including only one horizontal flat portion 11b. A plurality of through holes 13b are defined in the flat plate portion 11b. Each of the through holes 13b is disposed corresponding to an electrode pad 32 of a light emitting diode 30 and vertically penetrates the substrate 10b. A plurality of metal layers 23b are laid on the lower surface of the substrate 10b, and the metal layers 23b are spaced apart from each other, and the bottom ends of the through holes 13b are respectively sealed. Each of the metal layers 23b includes a conductive post 231b received in the corresponding through hole 13b to electrically connect the electrode pad 32 of the light emitting diode 30. The reflection portion 50b is formed on the outer surface of the vertical portion 12b and is annularly provided on a portion of the outer surface of the package 40 adjacent to the substrate 10b. The light emitting diode package structure 300 of the present embodiment is laid on the lower surface of the transparent substrate 10b by using the metal layer 23b, and is electrically connected to the light emitting diode 30, and can also emit light while functioning as an electrical connection. The light emitted from the diode 30 to the metal layer 23b is reflected, thereby forming a substantially U-shaped reflecting surface surrounding the light-emitting diode 30 together with the reflecting portion 50b, and effectively reflecting the light emitted from the light-emitting diode 30. The light exiting from the light-emitting surface 41 of the package 40 improves the light-emitting efficiency and makes the light output uniform. In addition, a phosphor layer 80 is formed on the outer surface of the package 40.

Please refer to FIG. 4 , which is a manufacturing method of the LED package structure 100 in the first embodiment, and the steps thereof include:

Referring to FIG. 5 at the same time, a transparent carrier 60 is provided. The carrier 60 is substantially rectangular. One surface of the carrier 60 is recessed inwardly to form a plurality of grooves 61. The carrier 60 is made of a transparent material such as glass.

Referring to FIG. 6, a light-emitting diode 30 is disposed in each of the grooves 61 of the carrier 60. The light-emitting diode 30 includes a light-emitting diode chip 31 and an electrode pad 32. The polar body wafer 31 faces the groove 61 and is attached to the bottom surface of the groove 61 so that the electrode pad 32 is disposed toward the opening direction of the groove 61.

Referring to FIG. 7, a concave plate 70 is provided. The concave plate 70 includes a horizontal first plate body 71 and a vertical second plate body 72 disposed around the periphery of the first plate body 71. The first plate The size of the body 71 is comparable to the size of the carrier 60. The first plate body 71 includes a first surface 711 facing the carrier plate 60 and a second surface 712 opposite to the first surface 711. The opposite ends of the first plate body 71 are respectively provided with a through hole 173. Each of the through holes 713 extends from the second surface 712 to the first surface 711, and the first electrode 21 and the first electrode 21 are respectively formed in the through hole 713. Two electrodes 22. The first surface 711 is provided with a plurality of metal layers 23, and the metal layer 23 is spaced apart from the first electrode 21 and the second electrode 22, respectively.

Referring to FIG. 8 , the concave plate 70 is covered on the carrier 60 , and the first electrode 21 , the second electrode 22 , and the metal layer 23 are respectively connected to the electrode pads 32 of the LEDs 30 . The structure is flipped, that is, the light emitting diode package structure 100 is formed, as shown in FIG. The first plate body 71 is formed as a substrate 10, and the second plate body 72 is formed as a reflection portion 50.

The manufacturing method of the LED package structure 200 in the second embodiment is similar to the method of fabricating the LED assembly 100 in the first embodiment, and the difference is only in the structure of the concave plate provided. Specifically, the structure of the concave plate provided is the same as that of the substrate 10a. The manufacturing method of the light emitting diode package structure 300 in the third embodiment is similar to the manufacturing method of the light emitting diode 100 in the first embodiment described above, except that the structure of the concave plate provided is different, and the specific The structure of the concave plate provided is the same as that of the substrate 10b.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

100, 200, 300. . . Light emitting diode package structure

10, 10a, 10b. . . Substrate

11. . . Upper surface

11b. . . Flat section

12. . . lower surface

12b. . . Vertical part

13. . . side

14. . . Through hole

20. . . electrode

twenty one. . . First electrode

twenty two. . . Second electrode

23, 23a, 23b. . . Metal layer

231b. . . Conductive column

24a. . . Insulating block

30. . . Light-emitting diode

30a. . . First light emitting diode

30b. . . Second light emitting diode

30c. . . Third light emitting diode

31. . . Light-emitting diode chip

311. . . Luminous surface

312. . . Back surface

32. . . Electrode pad

40. . . Package

41. . . Glossy surface

42. . . Joint surface

43. . . Outer side

44, 61. . . Groove

50, 50b. . . Reflection section

60. . . Carrier board

70. . . Concave plate

71. . . First plate

711. . . First surface

712. . . Second surface

13b, 713. . . perforation

72. . . Second plate

80. . . Fluorescent layer

1 is a cross-sectional view showing a light emitting diode package structure according to a first embodiment of the present invention.

2 is a cross-sectional view showing a light emitting diode package structure according to a second embodiment of the present invention.

3 is a cross-sectional view showing a light emitting diode package structure according to a third embodiment of the present invention.

4 is a flow chart showing a method of manufacturing a light emitting diode package structure according to an embodiment of the present invention.

5 to FIG. 8 are schematic cross-sectional views showing a light emitting diode package structure obtained in each step of a manufacturing process of a light emitting diode package structure according to an embodiment of the present invention.

100. . . Light emitting diode package structure

10. . . Substrate

11. . . Upper surface

12. . . lower surface

13. . . side

14. . . Through hole

20. . . electrode

twenty one. . . First electrode

twenty two. . . Second electrode

twenty three. . . Metal layer

30. . . Light-emitting diode

30a. . . First light emitting diode

30b. . . Second light emitting diode

30c. . . Third light emitting diode

31. . . Light-emitting diode chip

311. . . Luminous surface

312. . . Back surface

32. . . Electrode pad

40. . . Package

41. . . Glossy surface

42. . . Joint surface

43. . . Outer side

44. . . Groove

50. . . Reflection section

Claims (10)

A light emitting diode package structure comprising an electrode, a plurality of light emitting diodes electrically connected to the electrode, and a package covering the light emitting diode, wherein the electrode comprises a plurality of metal layers spaced apart from each other a surface of the package adjacent to the electrode is provided with a recess corresponding to the light emitting diode, and the light emitting diode is received in the recess and connected to the electrode by an electrode pad, and the package is close to the electrode The peripheral portion is surrounded by a reflecting portion. The light emitting diode package structure of claim 1, further comprising a substrate supporting the electrode, the light emitting diode and the package on the upper surface thereof, wherein the substrate is formed with a plurality of through holes. The electrode further includes a first electrode and a second electrode respectively received in the through hole, a top end of the first electrode and the second electrode being higher than an upper surface of the substrate, and a bottom end of the first electrode and the second electrode It is flush with the lower surface of the substrate. The light emitting diode package structure according to claim 2, wherein the metal layer is formed on an upper surface of the substrate, and forms a reflecting surface together with the reflecting portion to reflect light emitted by the light emitting diode. The difference in height between the tips of the first electrode and the second electrode and the upper surface of the substrate is equal to the thickness of the metal layer. The light emitting diode package structure according to claim 2, wherein the substrate comprises an outer side surface connected between the upper surface and the lower surface, and the reflecting portion is further disposed on the outer side surface of the substrate. . The light-emitting diode package structure of claim 1, wherein each adjacent two metal layers are connected by an insulating block, and the insulating block and the metal layer together form a light-emitting diode and a package. The substrate on which it is attached. The light emitting diode package structure according to claim 5, wherein the reflecting portion is further disposed on an outer side surface of the substrate. The light emitting diode package structure of claim 1, further comprising a substrate carrying the electrode, the light emitting diode and the package on the upper surface thereof, the substrate being made of a transparent material, A plurality of perforations are respectively disposed at positions of the electrode pads corresponding to the LEDs in the substrate, and the metal layers are laid on the lower surface of the substrate and respectively seal the bottom ends of the perforations, and each metal layer is included in the corresponding The conductive pillars in the perforations are electrically connected to the corresponding electrode pads. The light emitting diode package structure according to any one of the preceding claims, wherein the package has a plurality of grooves and corresponds to a plurality of spaced light emitting diodes. The package body is formed on a surface adjacent to the electrode, and the package body is integrally formed from a glass material. A method for manufacturing a light emitting diode package structure, comprising the steps of:
Providing a transparent carrier plate, one of the surfaces of the carrier plate is recessed inwardly to form a plurality of grooves, and the carrier plate is made of a transparent material;
a light emitting diode is disposed in the recess of the carrier, the light emitting diode includes a light emitting diode wafer and an electrode pad, and the electrode pad is disposed toward the opening direction of the groove;
Providing a concave plate, the concave plate comprising a plurality of separate metal layers and a reflection portion disposed on a periphery of the metal layer;
The concave plate is disposed on the carrier, and the electrode pads of the LED chip are electrically connected to the metal layer, and the reflection portion is disposed on the outer surface of the carrier. The method for manufacturing a light emitting diode package structure according to claim 8, wherein the concave plate comprises a horizontal first plate body and a vertical second plate body disposed around the periphery of the first plate body. The metal layers are formed on the first plate body at intervals, and the second plate body is formed as a reflection portion.