TWI412163B - Led package structure and the method of manufacturing the same - Google Patents

Abstract

The present invention provides an LED package structure and the method of manufacturing the same. The reflection portion of the LED package includes an insulative layer, a metal layer and a transparent layer.

Description

Light-emitting diode package structure and manufacturing method thereof

The invention relates to a package structure, in particular to a light emitting diode package structure, and to a method for manufacturing a light emitting diode package structure.

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 used as a new type of illumination source. In various fields, such as street lights, traffic lights, signal lights, spotlights and decorative lights.

In the prior art, in order to increase the luminous efficiency of the light-emitting diode, a reflective layer is generally formed around the light-emitting diode wafer in the fabrication process of the light-emitting diode package structure, and the reflection efficiency is higher when the metal is used as the reflective layer. Non-metal is much higher as a reflective layer. However, the use of metal as a reflective layer tends to cause electrical problems during the electrical connection of the wafer, resulting in a complicated fabrication process.

In view of this, the present invention is directed to a light emitting diode package structure having good reflection efficiency and a method of fabricating the same.

A manufacturing method of a light emitting diode package structure, comprising the steps of: forming a substrate And forming a circuit structure on the substrate; forming a reflective structure, the reflective structure comprises an insulating layer, a metal layer and a transparent layer, the metal layer is located between the insulating layer and the transparent layer, and the insulating layer, the metal layer and the transparent layer are disposed in the reflective structure The through hole is disposed on the substrate, wherein the insulating layer is in contact with the substrate; the light emitting diode chip is fixed in the through hole of the reflective structure and electrically connected to the circuit structure; and the package layer is formed to cover the light emitting diode chip And cutting the substrate to form a plurality of light emitting diode package structures.

A light emitting diode package structure comprising a substrate, a circuit structure disposed on the substrate, a reflective structure mounted on the substrate, a plurality of light emitting diode chips mounted on the substrate and electrically connected to the circuit structure, and covering An encapsulation layer of the LED substrate, the reflective structure includes an insulating layer, a metal layer and a transparent layer, the metal layer is located between the insulating layer and the transparent layer, the insulating layer is in contact with the substrate, and the reflective structure has a through-insulation layer, The metal layer and the transparent layer are perforated, and the light emitting diode chip is mounted in the through hole.

By using a reflective structure composed of an insulating layer, a metal layer and a transparent layer in turn, it is possible to use a metal having a high reflectance as a reflective layer to increase the reflection effect, and also to effectively avoid the light-emitting diode wafer by having an insulating layer. The poor electrical problems caused by the connection to the circuit make the manufacturing process simple.

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

10‧‧‧Substrate

12‧‧‧ Circuit structure

14‧‧‧Reflection Cup

16‧‧‧ dent

20, 70‧‧‧reflective structure

21, 71‧‧‧ insulation

22, 72‧‧‧ metal layer

23, 73‧‧‧ transparent layer

24‧‧‧Perforation

25‧‧‧ hole

26‧‧‧ outer surface

27‧‧‧Receiving area

30‧‧‧Light Emitter Wafer

32‧‧‧Wire

40, 80‧‧‧Encapsulation layer

42‧‧‧Fluorescent conversion materials

50, 60‧‧‧Light emitting diode package structure

1 is a schematic flow chart showing the steps of a method for fabricating a light emitting diode package structure according to the present invention.

2 is a view showing the first step of the manufacturing method of the light emitting diode package structure of the present invention; A schematic cross-sectional view of a photodiode package structure.

3 is a cross-sectional view showing a light emitting diode package structure obtained in the second step of the manufacturing method of the light emitting diode package structure of the present invention.

4 is a schematic top plan view of a light emitting diode package structure obtained in the second step of the manufacturing method of the light emitting diode package structure of the present invention.

5 is a cross-sectional view showing a light emitting diode package structure obtained in the third step of the method for fabricating a light emitting diode package structure of the present invention.

6 is a cross-sectional view showing a light emitting diode package structure obtained in the fourth step of the method for fabricating a light emitting diode package structure of the present invention.

7 is a cross-sectional view showing a light emitting diode package structure obtained in the fifth step of the method for fabricating a light emitting diode package structure of the present invention.

8 is a cross-sectional view showing a light emitting diode package structure obtained in the sixth step of the method for fabricating a light emitting diode package structure of the present invention.

FIG. 9 is a cross-sectional view showing a light emitting diode package structure according to another embodiment of the present invention.

As shown in FIG. 8, a light emitting diode package structure 50 according to an embodiment of the present invention includes a substrate 10, a circuit structure 12 disposed on the substrate 10, and a reflective cup 14 attached to the upper surface of the substrate 10 and the inner wall of the reflective cup 14. And a reflective structure 20, a light-emitting diode chip 30 mounted on the substrate 10 and disposed in the reflective cup 14 while being electrically connected to the circuit structure 12, and an encapsulation layer covering the light-emitting diode wafer 30 in the reflective cup 14. 40. The reflective structure 20 includes an insulating layer 21, a metal layer 22, and a transparent layer 23 in order from bottom to top. A through hole 24 is formed at the bottom of the structure 20, and the light emitting diode chip 30 is received in the through hole 24. A fluorescent conversion material 42 is suspended in the encapsulation layer 40.

As shown in FIG. 9, a light emitting diode package structure 60 according to another embodiment of the present invention includes a substrate 10, a circuit structure 12 disposed on the substrate 10, and a reflective structure 70 attached to the upper surface of the substrate 10, which is mounted on the substrate. A light emitting diode chip 30 on the 10 and electrically connected to the circuit structure 12, and an encapsulation layer 80 covering the light emitting diode chip 30. The difference from the foregoing embodiment is that the substrate 10 has no reflective cup, the reflective structure 70 is a flat plate laid on the substrate 10, and the insulating layer 71, the metal layer 72 and the transparent layer 73 are laid from bottom to top. The encapsulation layer 80 covers the substrate 10 and covers the LED array 30.

Hereinafter, a method of manufacturing the light emitting diode package structure of the present invention will be described in detail in conjunction with other drawings and embodiments.

1 is a flow chart showing the steps of a method for fabricating a light emitting diode package structure according to an embodiment of the invention. Referring to FIG. 2 at the same time, the substrate 10 is first provided, and at the same time, the circuit structure 12 is mounted on the substrate 10. The substrate 10 is a ceramic plate. The circuit structure 12 can be formed on the substrate 10 by mechanical, etching or laser processing techniques, and then formed by sputtering, electroplating, electroforming or evaporation. The circuit structure 12 can also be a thermoelectrically separated structure, that is, the transfer paths of thermal energy and electrical energy are different from each other. A plurality of reflective cups 14 may be formed on the substrate 10. The plurality of reflective cups 14 may be integrally formed with the substrate 10 or may be separately formed. The plurality of reflector cups 14 form a plurality of recesses 16 together with the substrate 10. The plurality of recesses 16 have an inverted trapezoidal cross-sectional shape, and the shape of the recesses 16 may be circular or rectangular, depending on the shape of the inner wall of the reflector cup 14. In the present embodiment, the reflective cup 14 is surrounded by a rectangular recess 16.

Referring to FIG. 3 and FIG. 4 simultaneously, a reflective structure 20 is further formed. The reflective structure 20 includes an insulating layer 21, a metal layer 22 and a transparent layer 23 in this order from bottom to top. The insulating layer 21 may be of the same material as the substrate 10, such as ceramics or the like. The metal layer 22 is made of a metal having high reflectance such as silver or the like. The transparent layer 23 can be glass or other transparent material. The three-layer material can be integrally formed by injection molding or molding, and can of course be formed by co-firing or pasting after separate molding. The outer surface 26 of the reflective structure 20 (i.e., the outer contour of the insulating layer 21) is matched with the recess 16 of the substrate 10 described above, and an inverted trapezoidal accommodating region 27 is formed therein. The bottom of the reflective structure 20 is provided with a through hole 24 for accommodating the LED chip 30. Therefore, the shape of the through hole 24 depends on the shape and size of the LED chip 30, so that it can be placed. It is preferred to incorporate a light emitting diode chip 30. The number of the perforations 24 depends on the number of light-emitting diode chips 30 to be loaded. A plurality of small holes 25 are defined in the bottom of the reflective structure 20 for electrically connecting the LEDs 30 through the plurality of small holes 25 when the LEDs 30 are electrically connected to the circuit structure 12. In this embodiment, a rectangular through hole 24 is formed in the bottom of the reflective structure 20, and a small rectangular small hole 25 is formed on each side of the through hole 24. Of course, in other embodiments, if the LED chip 30 is electrically connected without using a die bonding method, only the through hole 24 for accommodating the LED chip is required at the bottom of the reflective structure 20.

As shown in FIG. 5, the reflective structure 20 is mounted on the substrate 10. The outer surface 26 of the reflective structure 20 is in close contact with the inner wall of the reflective cup 14, the bottom is in close contact with the substrate 10, and the top is flush with the upper edge of the reflective cup 14. The reflective structure 20 is then secured to the substrate 10 in the reflective cup 14 by a sintering technique. At this time, the outer surface and the bottom surface of the insulating layer 21 are bonded to the inner wall of the reflector cup 14 and the substrate 10, respectively.

As shown in FIG. 6, the LED wafer 30 is electrically connected to the circuit structure 12 and disposed within the reflective cup 14. The illuminating diode chip 30 is placed on the substrate 10 and is disposed in the through hole 24 at the bottom of the reflective structure 20. In the embodiment, the illuminating diode chip 30 and the circuit structure are passed through the wire 32 by using a solid crystal wire bonding method. 12 connected. In other embodiments, it may be completed by flip chip or eutectic depending on the circuit structure.

FIG. 7 is a schematic diagram of forming an encapsulation layer 40 covering the LED array 30. The encapsulant is injected into the accommodating area 27 of the reflective structure 20 to cover the illuminating diode chip 30 and the wires 32. The encapsulating glue is not completely hardened, and the encapsulating glue is applied to the encapsulant and the reflective cup 14 and the reflective structure 20 by a compression molding process. Along the level. The encapsulating layer 40 is formed after the encapsulant is completely cured. Before the step of injecting the encapsulant, the fluorescent conversion material 42 may be added into the encapsulant to inject the encapsulant into the reflective structure 20 to suspend the fluorescent conversion material 42 in the encapsulation layer 40. Of course, in other embodiments, the fluorescent conversion material may be uniformly applied to the upper surface of the encapsulation layer 40 (not shown) after being encapsulated and encapsulated, and also functions to change optical properties. The fluorescent conversion material 42 may be garnet-based phosphor powder, citrate-based phosphor powder, orthosilicate-based phosphor powder, sulfide-based phosphor powder, thiogallate-based phosphor powder, and nitrogen. Compound-based phosphor powder.

Finally, the LED package structure that completes the packaging step is cut to obtain a plurality of separate LED package structures 50, as shown in FIG.

The reflective structure 20 is composed of three layers of an insulating layer 21, a metal layer 22 and a transparent layer 23. The insulating layer 21 can keep the metal layer 22 and the bottom connected circuit structure 12 insulated, thereby avoiding poor electrical properties during the packaging process. problem. The intermediate metal layer 22 has higher reflectivity than other non-metal materials, and can effectively improve the light-emitting efficiency of the light-emitting diode package structure. The transparent layer 23 on the metal layer 22 can transmit light through The clear layer 23 is directed toward the metal layer 22 to achieve a reflection effect, and at the same time, the metal layer 22 is separated from the encapsulant, so that the metal layer 22 has good stability and ensures the yield of the LED package structure.

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.

Claims (10)

A manufacturing method of a light emitting diode package structure, comprising the steps of: forming a substrate and forming a circuit structure on the substrate; forming a reflective structure, the reflective structure comprising an insulating layer, a metal layer and a transparent layer, wherein the metal layer is located in the insulating layer and the transparent layer Between the reflective structure, a through hole is formed through the insulating layer, the metal layer and the transparent layer; the reflective structure is mounted on the substrate, wherein the insulating layer is in contact with the substrate; and the light emitting diode chip is fixed in the through hole of the reflective structure And electrically connected to the circuit structure; forming an encapsulation layer covering the LED body; and cutting the substrate to form a plurality of LED packages. The method for manufacturing a light emitting diode package structure according to claim 1, wherein the substrate has a plurality of reflective cups, and the reflective cup and the substrate are integrally formed or separately formed. The method for manufacturing a light emitting diode package structure according to claim 2, wherein the shape of the reflective structure corresponds to a shape of a reflective cup, and the reflective structure is sintered and fixedly connected to the reflective cup and the substrate. The method for manufacturing a light emitting diode package structure according to claim 1, wherein the reflective structure further has at least one small hole, and the light emitting diode chip is electrically connected to the circuit structure by using a solid crystal wire bonding technique, and the wire Connected to the circuit structure via the at least one aperture. A method of manufacturing a light emitting diode package structure according to claim 1, The light emitting diode chip is electrically connected to the circuit structure by flip chip or eutectic technology. The method of fabricating a light emitting diode package structure according to claim 1, wherein the encapsulation layer comprises a fluorescent conversion material. A light emitting diode package structure comprising: a substrate; a circuit structure disposed on the substrate; a reflective structure mounted on the substrate, the reflective structure comprising an insulating layer, a metal layer and a transparent layer, wherein the metal layer is located in the insulating layer and the transparent layer Between the reflective structure, a through hole penetrating the insulating layer, the metal layer and the transparent layer; a light emitting diode chip mounted on the substrate and electrically connected to the circuit structure, the light emitting diode chip being mounted on the reflective structure Inside the perforation; and an encapsulation layer covering the LED substrate. The light emitting diode package structure of claim 7, wherein the reflective structure is connected to the substrate by a sintering technique. The light emitting diode package structure of claim 7, further comprising a reflective cup disposed on the substrate, the reflective structure being disposed in the reflective cup, and the light emitting diode chip being disposed at the bottom of the reflective cup. The light emitting diode package structure of claim 7, wherein the reflective structure further has at least one small hole, and the light emitting diode chip is electrically connected to the circuit structure by wire bonding, and the wire passes through the wire. The at least one small hole electrically connects the light emitting diode chip and the circuit structure.