TWI672832B - Wafer level light emitting diode packaging method and structure thereof - Google Patents

Abstract

The method of the present invention is for packaging a plurality of light-emitting diode chips on a wafer protective film, which mainly forms a package surface layer on the first electrodes of the light-emitting diode chips, and then forms a surface on the package surface layer. Connecting a lead electrode of the first electrode, cutting the light emitting diode chips, sorting and testing the light emitting diode chips, and covering the light emitting diode wafers with an encapsulation layer Forming a plurality of common electrodes on the side of the package layer by drilling and filling the conductive material, and then printing the plurality of common lines, and electrically connecting each of the common lines to the common electrode and the plurality of the lead electrodes. Finally, the circuit protection layer is covered, and the process is completed. According to the invention, the package is directly packaged on the wafer protection film, and the package substrate is not required, and the cost can be reduced and the speed of the process production can be improved by means of the printed circuit.

Description

Wafer level light emitting diode packaging method and structure thereof

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

The conventional LED package is a wire bond to connect the electrodes of the LED and the package substrate. Since it needs to be bonded one by one, the application requirements for the multi-chip will be The production speed and yield cannot meet the requirements; and the way of wire bonding is difficult to reduce in volume, and the impedance is high, and it is difficult to meet the application requirements of light, thin, small and high brightness.

The emergence of Flip chip packaging technology solves the problem that the volume is difficult to shrink, which can greatly reduce the volume after packaging, and meet the needs of light, thin, small and high brightness. However, in the flip chip packaging process, the wafer needs to be accurately positioned and placed and placed at a specified position on the package substrate. However, since the size of the wafer of the light-emitting diode is smaller, the stability of the wafer transfer is not improved. It is easy to have abnormalities such as wafer rotation, offset, material drop, etc., and the size of the nozzle is small in size in order to conform to the size of the wafer, and the nozzle is clogged and the suction is insufficient, resulting in insufficient suction. Waste of efficiency and increased production costs.

Accordingly, the main object of the present invention is to disclose a method of packaging a light-emitting diode chip on a wafer protective film.

A secondary object of the present invention is to disclose a package structure formed by directly performing a light emitting diode package on a wafer protective film.

The present invention is a wafer level light emitting diode package method for packaging a plurality of light emitting diode chips. The light emitting diode chips are not separated and assembled to form a wafer, and the wafer is adhered to a wafer protection. On the film, the LED chips have a first electrode and a second electrode on the upper and lower sides, and the packaging method comprises the following steps: Step S1: covering the encapsulant, step S2: drilling the blind hole, step S3: forming Deriving the electrode, step S4: cutting, step S5: sorting test, step S6: constructing the package body, step S7: forming a common electrode, step S8: forming a common line and step S9: forming a line protection layer.

Step S1 is to cover a surface of the package with a package surface layer covering the first electrode of the LED chip; and step S2 is for the position of the package surface corresponding to the LED chip. Drilling to form a plurality of blind holes, the blind holes revealing the first electrodes of the LED chips; step S3 is to fill the blind holes with conductive materials to form a plurality of lead electrodes, respectively Electrically connecting the first electrodes of the LED chips; step S4 is to cut the wafers to separate the LED chips into a single body; and Step S5 is to process the LED chips. Performing a test to remove the damaged LED chip and rearranging the remaining LED sub-groups on the wafer protection film, and the wafer protection film defines a plurality of package regions, and the same grouping The light emitting diode chips are located in the same package area; step S6 is to form an encapsulation layer on the wafer protection film, the package layer covers the side edges of the light emitting diode chips, and the package Forming a coplanar surface with the package surface layer; step S7 is to drill holes in the package layer of each package region, and forming a plurality of through holes on the package layer, and filling the conductive holes to fill the conductive holes a plurality of common electrodes; step S8 is to simultaneously print a plurality of common electric lines on the package layer and the package surface layer, and each of the package areas is correspondingly disposed with one of the common lines, and one of the common lines is electrically connected to the package area The common electrode and the derivation electrode; step S9 is to form a line protection on the encapsulation layer and the package surface layer a layer, the circuit protection layer covering the encapsulation layer and the derivation electrodes on the package surface layer, the common electrodes, and the common electric lines.

According to the above method, after the dicing, a wafer level light emitting diode package structure can be formed, which comprises at least two light emitting diode chips, a package surface layer, at least two lead electrodes, an encapsulation layer, a common electrode, and a common line. And a circuit protection layer, wherein the light-emitting diode wafers have first and second electrodes on the upper and lower sides, the package surface covers the first electrodes of the light-emitting diode wafers; the package surface layer has at least two blind holes The blind holes pass through the surface of the package at positions corresponding to the light-emitting diode chips, and expose the first electrodes of the light-emitting diode chips; the lead-out electrodes are filled in the blind holes, and the The lead electrodes are electrically connected to the first electrodes of the LED chips; the encapsulation layer covers the sides of the LED chips, and the encapsulation layer is coplanar with the package surface layer, and The encapsulation layer has a through hole extending through the two sides; the common electrode is filled in the through hole; the common electric line is disposed on the encapsulation layer and the package surface layer, and the common electric line is electrically connected to the common electrode and These leading-out electrode; the circuit protective layer covering the plurality of the encapsulation layer on the surface of the package deriving electrode, the common electrode and the common electrical line.

As described above, the present invention performs a packaging process directly on the wafer protective film, thereby eliminating the need for a package substrate, and by means of a printed circuit, the cost can be reduced and the speed of process production can be improved to meet the manufacturing requirements.

Step S1‧‧‧ Covering the package adhesive

Step S2‧‧‧Drilling blind holes

Step S3‧‧‧ Forming the derivation electrode

Step S4‧‧‧ cutting

Step S5‧‧‧ Sorting test

Step S6‧‧‧Constructing the package body

Step S7‧‧‧ forming a common electrode

Step S8‧‧‧ forming a common line

Step S9‧‧‧ forming a line protection layer

Step S10‧‧‧ Finished cutting

10‧‧‧ wafer

11‧‧‧Light Emitting Diode Wafer

12‧‧‧ wafer protective film

13‧‧‧First electrode

14‧‧‧second electrode

15‧‧‧Cutting area

20‧‧‧Package surface

21‧‧‧Blind holes

22‧‧‧Derived electrode

30‧‧‧Package area

40‧‧‧Encapsulation layer

41‧‧‧through holes

42‧‧‧Common electrode

50‧‧‧Communication lines

60‧‧‧Line protection layer

FIG. 1 is a step diagram of a packaging method of the present invention.

2A-2K are schematic structural views of a packaging method of the present invention.

3 is a top plan view of the package structure of the present invention.

Figure 4 is a bottom plan view of the package structure of the present invention.

Figure 5 is a cross-sectional view taken along line A-A of Figure 3 of the present invention.

In order to give your members a better understanding and recognition of the features, objects and effects of the present invention, a preferred embodiment will be described with reference to the following figures: Please refer to FIG. 1 and FIG. 2A to FIG. 2K. The present invention is a wafer level light emitting diode package method for packaging a plurality of light emitting diode chips 11. As shown in FIG. 2A, the light emitting diode chips 11 are not separated and assembled to form a wafer 10, and The wafer 10 is adhered to a wafer protective film 12, and the LEDs 11 have a first electrode 13 and a second electrode 14 on the upper and lower sides, and the LEDs 11 There is a cutting zone 15 therebetween.

As shown in FIG. 1, the packaging method of the present invention comprises the step S1: covering the encapsulant, step S2: drilling a blind hole, step S3: forming a derivation electrode, step S4: cutting, step S5: sorting test, step S6: constructing the package Main body, step S7: forming a common electrode, step S8: forming a common electric line and step S9: forming a line protective layer.

As shown in FIG. 2B, the upper surface of the wafer 10 is covered with a package surface layer 20, and the package surface layer 20 covers the first electrode 13 of the light-emitting diode wafers 11. The package surface layer 20 may be selected from the ring. Any one of an epoxy resin and a silicone resin, and the package skin 20 is formed on the wafer 10 by using a stamper, a dispensing, or the like.

As shown in FIG. 2C, in step S2, a plurality of blind holes 21 are formed by drilling the positions of the package surface layer 20 corresponding to the light-emitting diode chips 11, and the blind holes 21 expose the light-emitting diode chips 11. The first electrode 13 may be drilled in any manner selected from the group consisting of a laser and a drill. As long as the blind holes 21 can be formed, the requirements for use are satisfied.

As shown in FIG. 2D, in step S3, the blind holes 21 are respectively filled with a conductive material to form a plurality of lead-out electrodes 22, and the lead-out electrodes 22 are electrically connected to the light-emitting diode wafers 11, respectively. The first electrode 13; the conductive material is Conductive Silver Adhesive or Conductive Nano Silver Adhesive.

As shown in FIG. 2E, step S4 is to cut the wafer 10, and cut along the cutting area 15 to separate the light-emitting diode wafers 11 into a single individual, which can use techniques such as lightning cutting. Cut.

As shown in FIG. 2F, in step S5, the LEDs 11 are tested to remove the damaged LEDs 11. This process is no different from the conventional wafer test, and the purpose is to eliminate defective products; The present invention re-arranges the remaining light-emitting diode wafers 11 on the wafer protective film 12, and the wafer protective film 12 defines a plurality of package regions 30 (as shown in FIG. 2H), and the same grouping The LED arrays 11 are located in the same package area 30. In this step, the grouping and quantity of the LED chips 11 are set according to subsequent requirements, as shown in FIG. 2F. The plurality of light-emitting diode chips 11 in the package region 30 are three, and a wiring area required for packaging is reserved.

As shown in FIG. 2G, in step S6, an encapsulation layer 40 is formed on the wafer protection film 12. The encapsulation layer 40 covers the side edges of the LED sub-die 11, and the encapsulation layer 40 and the package surface layer 20 are formed. The material of the encapsulation layer 40 can also be selected from any one of epoxy resin (Epoxy) and Silicone resin, and the encapsulation layer 40 can be selected by using a stamper, a dispensing method, or the like. production.

As shown in FIG. 2H, step S7 is to drill holes in the encapsulation layer 40 of each of the package regions 30, and a plurality of through holes 41 are formed on the encapsulation layer 40. The drilling method of the through holes 41 is selected from the following steps. Any one of a laser and a drill bit, and the conductive holes are filled in the through holes 41 to form a plurality of common electrodes 42. The conductive materials are also Conductive Silver Adhesive or Conductive Nano Silver Adhesive.

As shown in FIG. 2I, step S8 is to simultaneously print a plurality of common electric lines 50 on the package layer 40 and the package surface layer 20, and each of the package areas 30 is correspondingly provided with the common electric line 50, and the common electric line 50 is disposed. The common electrode 42 and the lead-out electrode 22 in the package region 30 are electrically connected.

As shown in FIG. 2J, a circuit protection layer 60 is formed on the package layer 40 and the package surface layer 20, and the circuit protection layer 60 covers the package layer 40 and the lead-out electrodes 22 on the package surface layer 20, The common electrodes 42 and the common electric lines 50.

As shown in FIG. 2K, in addition, the present invention may further comprise a step S10: cutting the finished product, and step S10 is to cut the encapsulating layer 40 by using the encapsulating area 30 as a cutting unit.

Moreover, when the illuminating color of the illuminating diode chips 11 is a single color, at this time, a larger number of the illuminating diode chips 11 may be provided in one of the package regions 30, that is, a larger brightness can be provided. When the illuminating colors of the illuminating diodes 11 are respectively selected from the group consisting of red, green, and blue, the LEDs 11 of the same group can be three, and the three LEDs are The color of the body wafer 11 is red, green, and blue, respectively, which can be mixed to form a white light source.

Please refer to FIG. 3, FIG. 4 and FIG. 5 together, which is a wafer level light emitting diode package structure formed according to the above method steps S1-S10, as shown in the figure, which comprises at least two light emitting two. The polar body wafer 11, the package surface layer 20, the at least two lead-out electrodes 22, the encapsulation layer 40, the common electrode 42, the common electric line 50, and the line protection layer 60. The LEDs 11 have a first electrode 13 and a second electrode 14 on the upper and lower sides. The package surface 20 covers the first electrodes 13 of the LEDs 11; the package surface 20 has at least two blinds. Holes 21 passing through the package surface layer 20 at positions corresponding to the LED chips 11 and exposing the first electrodes 13 of the LED chips 11; the lead electrodes 22 are filled in The plurality of lead electrodes 21 are electrically connected to the first electrodes 13 of the LED chips 11 , wherein the light emitting diode chips 11 , the lead electrodes 22 and the blind electrodes Hole 21, in the figure, draws three representations.

The encapsulation layer 40 covers the sides of the LED array 11 , and the encapsulation layer 40 is coplanar with the package surface layer 20 , and the encapsulation layer 40 has a through hole 41 extending through the two sides; The common electrode 42 is filled in the through hole 41; the common line 50 is disposed on the package layer 40 and the package surface layer 20, and the common line 50 is electrically connected to the common electrode 42 and the lead electrodes 22; The line protection layer 60 covers the encapsulation layer 40 and the derivation electrode 22 on the encapsulation surface layer 20, the common electrode 42 and the common electric line 50.

With the structure as described above, the advantages of the present invention include at least:

1. Using the wafer protective film 12 as a package carrier, it is possible to save costs without using a package substrate.

2. In order to utilize the printing technology and simultaneously print a plurality of common electric lines 50, the speed of the process production can be improved.

3. The manufactured package structure can be directly on the board by SMT method, thereby improving production efficiency.

The above is only the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, that is, the equivalent variations and modifications made by the scope of the present invention are covered by the scope of the patent application of the present invention. .

Claims (10)

A wafer level light emitting diode package method for packaging a plurality of light emitting diode chips, wherein the light emitting diode chips are not separated and assembled to form a wafer, and the wafer is adhered to a wafer protective film, The light-emitting diode chip has a first electrode and a second electrode on the upper and lower sides, and the package method includes: step S1: covering the package adhesive, and step S1 is to cover a surface of the package on the upper surface of the wafer. The package surface layer covers the first electrodes of the LED chips; Step S2: drilling blind holes, and step S2 is to drill a plurality of blind holes in the package surface layer corresponding to the positions of the LED chips. The blind holes expose the first electrodes of the LED chips; Step S3: forming the derivation electrodes, and step S3 is to fill the blind holes with conductive materials to form a plurality of derivation electrodes, and the derivation electrodes are respectively electrically The first electrode of the light emitting diode chip is connected; step S4: cutting; step S4 is to cut the wafer to separate the light emitting diode wafers into a single individual; step S5: sorting test Step S5 is to test the LED chips, reject the damaged LED chip, and rearrange the remaining LED chips on the wafer protection film, and the wafer The protective film defines a plurality of package regions, and the same group of the LED chips are located in the same package region; Step S6: constructing the package body, and step S6 is to form an encapsulation layer on the wafer protection film, the package The layer covers the sides of the LED chips, and the encapsulation layer is equal to the package surface layer to form a coplanar surface; step S7: forming a common electrode, and step S7 is drilling the encapsulation layer of each of the package regions a plurality of through holes are formed in the encapsulation layer, and the plurality of through holes are filled in the through holes to form a plurality of common electrodes; Step S8: forming a common electric circuit, step S8 is to simultaneously print a plurality of common electric lines on the encapsulation layer and the package surface layer, and each of the package areas is correspondingly disposed with one common electric line, and the common electric line is electrically connected to the The common electrode and the lead-out electrode in the package area; step S9: forming a line protection layer, step S9 is to form a line protection layer on the package layer and the package surface layer, the line protection layer covering the package layer and the package surface layer The lead-out electrodes, the common electrodes, and the common lines. The wafer level LED package method according to claim 1, further comprising a step S10: finalizing the cutting, and step S10 is to cut the encapsulation layer by using the encapsulation area as a cutting unit. The wafer level light emitting diode package method of claim 1, wherein the light emitting color of the light emitting diode chips is a single color. The wafer level light emitting diode package method according to claim 1, wherein the light emitting color of the light emitting diode chips is any one selected from the group consisting of red, green and blue. The wafer-level light-emitting diode package method of claim 4, wherein the plurality of light-emitting diode chips of the same group are three, and the color of the three-light-emitting diode chip is red, respectively. Green and blue. The wafer level light emitting diode packaging method according to claim 1, wherein the drilling method of step S2 and step S7 is any one selected from the group consisting of a laser and a drill. A wafer-level light-emitting diode package structure comprising: at least two light-emitting diode chips, wherein the light-emitting diode chips have a first electrode and a second electrode on the upper and lower sides; a package surface layer covering the first electrode of the light emitting diode chip, the package surface layer having at least two blind holes, the blind holes passing through the package surface at positions corresponding to the light emitting diode wafers And exposing the first electrodes of the LED chips; at least two deriving electrodes, the deriving electrodes are filled in the blind holes, and the deriving electrodes are electrically connected to the LED chips respectively The first electrode; an encapsulation layer covering the side edges of the LED chips, and the encapsulation layer is coplanar with the package surface layer, and the encapsulation layer has a consistent hole penetrating the two sides a common electrode, the common electrode is filled in the through hole; a common electric circuit, the common electric line is disposed on the encapsulation layer and the package surface layer, and the common electric line is electrically connected to the common electrode and the derivation electrodes; And a line protection layer covering the encapsulation layer and the derivation electrodes, the common electrode and the common electric line on the encapsulation surface layer. The wafer-level light emitting diode package structure according to claim 7, wherein the light emitting color of the light emitting diode chips is a single color. The wafer level light emitting diode package structure according to claim 7, wherein the light emitting color of the light emitting diode chips is any one selected from the group consisting of red, green and blue. The wafer-level light-emitting diode package structure according to claim 9, wherein the light-emitting diode chips have three colors, and the three-light-emitting diode chips have red, green and blue colors respectively. .