CN209880656U

CN209880656U - LED array packaging structure

Info

Publication number: CN209880656U
Application number: CN201921058651.0U
Authority: CN
Inventors: 孙瑜; 刘丰满; 曹立强
Original assignee: Shanghai Xianfang Semiconductor Co Ltd
Current assignee: Shanghai Xianfang Semiconductor Co Ltd
Priority date: 2019-07-05
Filing date: 2019-07-05
Publication date: 2019-12-31
Anticipated expiration: 2029-07-05

Abstract

The utility model discloses a LED array packaging structure, include: the LED chip array comprises a front surface and a back surface, wherein each LED chip in the LED chip array is provided with the front surface and the back surface, and electrodes of the LED chips are arranged on the front surface; the transparent plastic packaging layer coats the back and the side of the LED chip; a re-layout wiring layer which is positioned above the transparent plastic packaging layer and the front surface of the LED chip and is electrically connected to the electrode of the LED chip; and a driving control chip electrically connected to the re-layout wiring layer.

Description

LED array packaging structure

Technical Field

The utility model relates to a LED encapsulates technical field, especially relates to a packaging structure of LED array.

Background

With the development of LED display, LED chips are smaller and smaller, and display density is higher and higher, and the conventional packaging manner of assembling LEDs on a PCB cannot meet the application of LED display with small pitch and high display density. Meanwhile, the whole LED display also needs to meet the requirements of narrow frames, small size and the like.

In the conventional LED array package structure, a control chip of the LED is usually mounted on the back of the LED display layer. However, the LED control chip is addressed and controlled in a row and column mode, and pins are few, so that the substrate for assembling the LED and the control chip is large in difference of wiring density of the front surface and the back surface, and the manufacturing difficulty of the substrate is increased.

In order to meet the requirement of the small-pitch high-density LED display package, an organic carrier process with narrow line width and line spacing is generally adopted. However, the difference between the pin density of the control chip and the pin density of the LED chip is large, so that the wiring density of the front side and the back side is very different, and the thickness of a metal layer is not uniform during the substrate manufacturing, thereby causing failure.

In order to overcome the front that current LED array encapsulation exists and back wiring density difference big, lead to the uneven, the inefficacy of packaging structure positive and negative metal level thickness and the great scheduling problem of the base plate preparation degree of difficulty, the utility model provides a novel LED array packaging structure, at least partial above-mentioned problem of having overcome.

SUMMERY OF THE UTILITY MODEL

The front that exists to current LED array package is big with back wiring density difference, leads to the uneven, the inefficacy of packaging structure positive and negative metal level thickness and the great scheduling problem of the base plate preparation degree of difficulty, according to the utility model discloses an embodiment provides a LED array package structure, includes:

the LED chip array comprises a front surface and a back surface, wherein each LED chip in the LED chip array is provided with the front surface and the back surface, and electrodes of the LED chips are arranged on the front surface;

the transparent plastic packaging layer coats the back and the side of the LED chip;

a re-layout wiring layer which is positioned above the transparent plastic packaging layer and the front surface of the LED chip and is electrically connected to the electrode of the LED chip; and

a drive control chip electrically connected to the re-layout wiring layer.

In one embodiment of the invention, the LED chip array comprises a plurality of red, green and blue LED chips.

In one embodiment of the present invention, the material of the transparent molding layer is resin.

In one embodiment of the invention, the re-layout wiring layer has N layers, N ≧ 1.

In one embodiment of the invention, the LED array package structure further comprises a dielectric layer for insulating the upper and lower redistribution wiring layers and the metal wiring.

In one embodiment of the present invention, the outermost layer of the re-layout wiring layer has a driving control chip pad and an external connection pad.

In one embodiment of the present invention, the driving control chip is flip-chip bonded to the driving control chip pad by a solder ball.

In one embodiment of the present invention, the driving control chip is electrically connected to the driving control chip pad by wire bonding.

The utility model provides a LED array packaging structure carries out the wafer reconsitution in through sealing LED array chip plastic envelope to transparent plastic envelope, spills LED chip pin at a side surface, and then carries out the laying out wiring again based on LED chip pin to form external pad and control chip pad on outmost laying out wiring layer again, then with control chip with flip-chip bonding or mode equipment such as lead bonding and electricity connection to the control chip pad. The utility model provides a this kind of LED array packaging structure adopts earlier to LED chip array plastic envelope, carries out the mode of rewiring fan-out again, has solved the inhomogeneous problem of wiring that the two-sided preparation metal level of base plate leads to.

Drawings

To further clarify the above and other advantages and features of various embodiments of the present invention, a more particular description of various embodiments of the invention will be rendered by reference to the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. In the drawings, the same or corresponding parts will be denoted by the same or similar reference numerals for clarity.

Fig. 1 illustrates a schematic cross-sectional view of an LED array package structure 100 formed in accordance with an embodiment of the present invention.

Fig. 2A to 2E show schematic cross-sectional views of a process of forming an LED array package structure 100 according to an embodiment of the present invention.

Fig. 3 shows a flow chart of forming an LED array package structure 100 according to an embodiment of the present invention.

Fig. 4 illustrates a schematic cross-sectional view of an LED array package structure 400 formed in accordance with yet another embodiment of the present invention.

Detailed Description

In the following description, the present invention is described with reference to embodiments. One skilled in the relevant art will recognize, however, that the embodiments may be practiced without one or more of the specific details, or with other alternative and/or additional methods, materials, or components. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of various embodiments of the invention. Similarly, for purposes of explanation, specific numbers, materials, and configurations are set forth in order to provide a thorough understanding of the embodiments of the invention. However, the invention may be practiced without specific details. Further, it should be understood that the embodiments shown in the figures are illustrative representations and are not necessarily drawn to scale.

Reference in the specification to "one embodiment" or "the embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment.

It should be noted that, the embodiments of the present invention describe the process steps in a specific order, however, this is only for the convenience of distinguishing the steps, and not for limiting the sequence of the steps.

An LED array package structure according to an embodiment of the present invention is described in detail below with reference to fig. 1. Fig. 1 illustrates a schematic cross-sectional view of an LED array package structure 100 formed in accordance with an embodiment of the present invention. As shown in fig. 1, the LED array package structure 100 further includes an LED chip array 110, a transparent molding layer 120, a redistribution layer 130, a dielectric layer 140, a control chip 150, and a soldering structure 160.

The LED chip array 110 is disposed on a first surface of the LED array package structure 100, and a light emitting surface of the LED chip array 110 faces the outside of the LED array package structure 100. In an embodiment of the present invention, the LED chip array 110 includes a plurality of red, green and blue LED chips, such as a red LED chip 110-1, a green LED chip 110-2 and a blue LED chip 110-3, and the layout thereof can be adjusted according to design requirements. In another embodiment of the present invention, the LED chip array 110 can also be a single color LED chip.

The transparent plastic package layer 120 is located on the first surface of the LED array package structure 100, and is wrapped on the surface of the LED chip 110 in a plastic package manner, so as to leak out of the electrodes of the LED chip 110. The transparent molding layer 120 may be resin, PI, or other materials.

The re-layout wiring layer 130 is disposed inside the transparent molding layer 120 and electrically connected to the electrodes of the LED chip array 110. In one embodiment of the present invention, the re-layout wiring layer 130 has a plurality of layers, wherein the first layer is electrically connected to the electrodes of the LED chip array 110, and the outermost layer is electrically connected to the driver chip pad 131 and the external connection pad 132. In one embodiment of the present invention, the redistribution layer 130 is a copper wire, and the multiple layers of wires are connected by a conductive via.

The dielectric layer 140 is disposed between the layers of the rewiring layer 130 and between the wirings of the same layer, and plays roles of insulation protection, mechanical support, and the like. In one embodiment of the present invention, the material of the dielectric layer 140 is polyimide PI.

The control chip 150 is used to provide driving power to the LED chip array 110 and perform display control, and is electrically connected to the driving chip pad 131 on the outermost layer of the re-layout wiring layer 130 through the soldering structure 160, and drives and controls the LED chip array 110 through the re-layout wiring layer 130.

The process of forming the LED array package structure 100 is described in detail below with reference to fig. 2A to 2E and fig. 3. Fig. 2A-2E illustrate schematic cross-sectional views of a process of forming an LED array package structure 100 according to an embodiment of the invention; fig. 3 shows a flow chart of forming an LED array package structure 100 according to an embodiment of the present invention.

First, in step 310, as shown in fig. 2A, the LED chip is mounted on the temporary carrier 220 to form an LED chip array 210, the electrode pins of the LED chip array 210 are close to the temporary carrier 220, and the light emitting surface of the LED chip array 210 faces upward. The temporary carrier 220 may be a rigid substrate such as glass or silicon wafer, and plays a role of mechanical support. In an embodiment of the present invention, the mounting of the LED chip array may be performed by a laser detachable bonding adhesive.

Next, at step 320, as shown in fig. 2B, the LED chip array 210 is plastic-encapsulated. After molding, the molding layer 230 covers the entire LED chip array 210, and plays a role in protection. The molding layer 230 may be a transparent material such as resin or PI.

Then, in step 330, as shown in fig. 2C, the temporary carrier 220 is removed. In an embodiment of the present invention, the LED chip array 210 is attached to the temporary carrier plate 220 by the laser detachable bonding glue, and when the temporary carrier plate 220 is removed, the temporary carrier plate 220 can be separated after laser irradiation.

Next, in step 340, as shown in fig. 2D, a redistribution layer 240 and an interlayer dielectric layer 250 are formed on the side of the transparent encapsulant layer 230 that leaks out of the electrodes of the LED chip array 210, the redistribution layer 240 is electrically connected to the electrodes of the LED chip array 210, and the outermost redistribution layer 240 further has a driver chip pad 241 and an external connection pad 242. In one embodiment of the present invention, the redistribution layer 240 may be formed by electroplating, and the material may be a metal material such as copper. In another embodiment of the present invention, in order to improve the rigid support and protection of the manufacturing process of the redistribution layer 240, the temporary slide can be bonded on the front surface of the transparent plastic encapsulant layer 230 and removed after the package structure is completed.

Finally, in step 350, as shown in fig. 2E, the driving control chip 260 is assembled into a package structure. In an embodiment of the present invention, the driving control chip can be flip-chip bonded to the package structure through the solder ball 270, and in another embodiment of the present invention, as shown in fig. 4, the LED driving control chip 450 is electrically connected to the driving chip pad 431 of the redistribution layer through the metal lead 460 by using a wire bonding process.

Based on this kind of LED array packaging structure, through carrying out the wafer reconsitution with LED array chip plastic envelope in transparent plastic envelope, spill LED chip pin at a side surface, carry out the rearrangement wiring based on LED chip pin next to form external pad and control chip pad on outmost rearrangement wiring layer, then with control chip with flip-chip bonding or mode equipment such as lead wire bonding and electricity connection to the control chip pad. The utility model provides a this kind of LED array packaging structure adopts earlier to LED chip array plastic envelope, carries out the mode of rewiring fan-out again, has solved the inhomogeneous problem of wiring that the two-sided preparation metal level of base plate leads to.

While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. It will be apparent to persons skilled in the relevant art that various combinations, modifications, and changes can be made thereto without departing from the spirit and scope of the invention. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.

Claims

1. An LED array package structure comprising:

a drive control chip electrically connected to the re-layout wiring layer.

2. The LED array package structure of claim 1, wherein said LED chip array comprises a plurality of red, green, and blue LED chips.

3. The LED array package structure of claim 1, wherein the material of the transparent molding layer is a resin.

4. The LED array package structure of claim 1, wherein the re-routing wiring layer has N layers, N ≧ 1.

5. The LED array package structure of claim 4, further comprising a dielectric layer for insulating the upper and lower redistribution routing layers and the metal routing.

6. The LED array package structure of claim 4, wherein an outermost layer of the re-routing wiring layer has a drive control chip pad and an external pad.

7. The LED array package structure of claim 6, wherein the drive control chip is flip-chip bonded to the drive control chip pad by solder balls.

8. The LED array package structure of claim 6, wherein the drive control chip is electrically connected to the drive control chip pad by wire bonding.