Light source device, preparation method thereof, and display device

Abstract

This application belongs to the field of display technology, and provides a light source device, a preparation method of the light source device, and a display device. The light source device includes a driving chip, at least one LED chip group, a circuit line layer, a channel wire, a first metal pad, and a second metal pad. Among them, the first metal pad is disposed on the first surface of the driving chip, the circuit line layer and the second metal pad are disposed on the second surface of the driving chip, and a channel wire is provided on the side surface of the driving chip for connecting the circuit line layer and the first metal pad. The LED chip group is disposed on the second surface of the driving chip and is connected to the second metal pad. By providing a channel wire on the side surface of the driving chip to connect the circuit line layer and the first metal pad on both sides of the driving chip, the size of the light source device is reduced, and the problem that the size of the existing light source body cannot be reduced due to the large size of the package is solved.

Description

Technical Field

[0001] This application relates to the field of display technologies, and particularly to a light source device, a preparation method of the light source device, and a display device. Background Art

[0002] In the display screen market, with the increasingly rapid technological development, transparent display screens have become the mainstream devices used in emerging markets. The main component of a transparent display screen is an integrated light source body that includes a driving chip and an LED (light-emitting diode) chip. The existing LED light source body uses a vertical structure packaging technology to fix the driving chip on a circuit carrier board in a flip-chip manner, fix the front-emitting LED chip adhesively directly above the driving chip, and then electrically connect the LED chip to the driving chip and the circuit carrier board by welding conduction wires, thereby realizing the driving of the integrated LED light source body.

[0003] However, the above design has the problem that the size of the package cannot be reduced because space for welding wires needs to be reserved on the circuit carrier board. Summary of the Invention

[0004] The purpose of this application is to provide a light source device, a preparation method of the light source device, and a display device, aiming to solve the problem that the size of the existing light source body package is large and cannot be reduced.

[0005] In the first aspect of the embodiments of this application, a light source device is provided, including: a driving chip, on a first surface of the driving chip, there are provided a plurality of first metal pads; on a second surface of the driving chip opposite to the first surface, there are provided a circuit line layer and a plurality of second metal pads, the circuit line layer connects the plurality of second metal pads; on a side surface of the driving chip connecting the first surface and the second surface of the driving chip, there are provided a plurality of channel conductors exposed outside the driving chip, the plurality of channel conductors connect the circuit line layer and respectively connect the plurality of first metal pads; and at least one LED chip group, the LED chip group is disposed on the second surface of the driving chip and is connected to the plurality of second metal pads.

[0006] Optionally, the light source device further includes: a circuit substrate, the driving chip is disposed on an upper surface of the circuit substrate and the first surface of the driving chip faces the upper surface of the circuit substrate, on a lower surface of the circuit substrate, there are provided a plurality of electrical contacts; and an outer encapsulation colloid, covering the driving chip and the LED chip group and connecting the periphery of the upper surface of the circuit substrate.

[0007] Optionally, the LED chip group includes a red light LED chip, a green light LED chip, and a blue light LED chip.

[0008] Optionally, the LED chip group and a plurality of the second metal pads are both located in the middle area of the second surface of the driving chip.

[0009] Optionally, at least one LED chip group is a plurality of the LED chip groups, and a plurality of the LED chip groups and a plurality of the second metal pads are both distributed in the four corner areas of the second surface of the driving chip.

[0010] Optionally, a plurality of the first metal pads are distributed in the peripheral area of the first surface of the driving chip.

[0011] A second aspect of the embodiments of the present application provides a method for manufacturing a light source device, and the manufacturing method includes:

[0012] Manufacturing a driving chip wafer, the driving chip wafer having a plurality of sub-blocks, a plurality of longitudinal cutting channels and a plurality of transverse cutting channels, the plurality of transverse cutting channels being perpendicular to the plurality of longitudinal cutting channels and dividing the plurality of sub-blocks separated from each other;

[0013] Forming a plurality of through holes in the plurality of longitudinal cutting channels and the plurality of transverse cutting channels, and filling conductive materials in the through holes to form channel wires;

[0014] Providing a plurality of first metal pads on the first surface of the sub-block, providing a circuit line layer and a plurality of second metal pads connecting the circuit line layer on the second surface of the sub-block opposite to the first surface of the sub-block, and connecting the channel wires to the first metal pads and the circuit line layer of two adjacent sub-blocks;

[0015] Cutting along the midline positions of the plurality of longitudinal cutting channels and cutting along the midline positions of the plurality of transverse cutting channels to form driving chips from the sub-blocks;

[0016] Providing a circuit carrier board, disposing a plurality of the driving chips on the upper surface of the circuit carrier board and the first surface of the driving chip facing the upper surface of the circuit carrier board, and a plurality of electrical contacts being provided on the lower surface of the circuit carrier board;

[0017] Disposing at least one LED chip group on the second surface of the driving chip and connecting the LED chip group to a plurality of the second metal pads of the driving chip;

[0018] Manufacturing an outer encapsulation layer, the outer encapsulation layer covering a plurality of the driving chips and a plurality of the LED chip groups and connecting the peripheral area of the upper surface of the circuit carrier board and the gap areas between the plurality of driving chips; and

[0019] Cutting and disconnecting the outer encapsulation layer and the circuit carrier board along the gap areas between the plurality of driving chips to obtain a plurality of light source devices.

[0020] Optionally, the circuit line layer and the plurality of second metal pads on the second surface of the sub-block are formed by etching a metal layer.

[0021] Optionally, the plurality of first metal pads of the sub-block are formed by a redistribution layer.

[0022] A third aspect of the embodiments of the present application provides a display device, including: a transparent conductive plate and a plurality of light source devices as described in any one of the above, the plurality of light source devices are arranged in an array on the transparent conductive plate, and the plurality of first metal pads on the first surface of the driving chip are electrically connected to the transparent conductive plate.

[0023] The light source device and its manufacturing method provided by the embodiments of the present application realize the electrical connection design of the double-sided circuit layer by utilizing the space of the wafer dicing channel for the driving chip. Compared with the limitation of the existing chip to design the circuit by avoiding the via position inside, the method of the embodiments of the present application is more flexible, enabling better densification of the internal design circuit, thereby releasing the area space of the driving chip. When packaging the light source body, it can achieve a smaller single body size. The driving chip formed in this way is integrally packaged with at least one LED chip group. Under the same performance conditions, it can achieve miniaturization and meet the requirement of improving the luminous brightness of the product. Therefore, when the product is applied to the transparent display device market, it can meet the requirements of smaller pitch and high brightness display without affecting the transparency effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic structural diagram of a light source device provided by the prior art;

[0025] Figure 2 A schematic structural diagram of another light source device provided by the prior art;

[0026] Figure 3 A schematic structural diagram of a driving chip provided by the embodiments of the present application;

[0027] Figure 4 A schematic structural diagram of a driving chip wafer provided by the embodiments of the present application;

[0028] Figure 5a 、 Figure 5b A schematic diagram of the surface circuit structure of the driving chip provided by the embodiments of the present application;

[0029] Figure 6a 、 Figure 6b An exploded view of the light source device provided by the embodiments of the present application;

[0030] Figure 7It is a schematic flowchart of a preparation method provided by an embodiment of the present application. Detailed implementation manners

[0031] In order to make the objectives, technical solutions and advantages of the present application more clear and understandable, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0032] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0033] In the description of the present application, it should be understood that the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features.

[0034] As Figure 1 shown, currently the main components of a transparent display screen are LED light source bodies (including driving chips and LED chips). Since the existing vertical structure packaging technology for LED light source bodies fixes and electrically connects the driving chip 11 to the circuit board 10 in a flip-chip manner, fixes the front-emitting LED chip 13 directly above the driving chip 11, then realizes electrical connection between the LED chip 13, the driving chip 11 and the circuit board 10 by welding conduction wires, and then performs encapsulation through a molded colloid 12 to realize an integrated light source of the driving chip and the LED chip. For the LED light source body realized by this technology, it is very difficult to miniaturize the size of the product, and a certain space for welding wires needs to be reserved on the circuit board 10, so that the size of the package cannot be reduced.

[0035] Although there is also a through-silicon via (TSV) technology in the prior art as Figure 2 shown, which fixes and electrically connects the driving chip 21 to the circuit board 20 in a flip-chip manner and flips the LED chip 23 on the driving chip 21. However, when designing the internal structure circuit 22 of the driving chip 21, the internal circuit of the chip must avoid the reserved space range required for making through-silicon vias. Such a design structure not only increases the difficulty of realizing the internal circuit of the driving chip 21, but also increases the design cost of the chip, and it is very difficult to reduce the area of the driving chip 21 designed in this way.

[0036] To solve the above technical problems, an embodiment of the present application provides a light source device. Combining Figure 3 , Figure 4 , Figure 5a , Figure 5b and as shown in FIG. 6, a light source device in an embodiment of the present application includes: a driving chip 40, a circuit line layer 03, channel conductors 04, a first metal pad 01, a second metal pad 02, and at least one LED chip group 50.

[0037] Specifically, a plurality of first metal pads 01 are provided on the first surface of the driving chip 40. On the second surface of the driving chip 40 opposite to the first surface, a circuit line layer 03 and a plurality of second metal pads 02 are provided. The circuit line layer 03 is connected to the plurality of second metal pads 02. On the side surface of the driving chip 40 connecting the first surface and the second surface of the driving chip 40, a plurality of channel conductors 04 exposed outside the driving chip 40 are provided. The plurality of channel conductors 04 are connected to the circuit line layer 03 and are respectively connected to the plurality of first metal pads 01. At least one LED chip group 50 is provided on the second surface of the driving chip 40 and is connected to the plurality of second metal pads 02.

[0038] In this embodiment, combining Figure 5b as shown, the circuit line layer 03 is connected to the plurality of second metal pads 02, and the plurality of second metal pads 02 are connected to the LED chip group 50. The circuit line layer 03 is used to provide a driving signal to the LED chip group 50. Since the circuit line layer 03 is provided on the second surface of the driving chip 40, line migration connection at unlimited positions of the plurality of second metal pads 02 can be realized, thereby reducing the size of the light source device. And on the side surface of the driving chip 40, a plurality of channel conductors 04 exposed outside the driving chip 40 are provided, and the vias 502 of the plurality of channel conductors 04 are provided on the dicing streets 501 of the wafer. After the wafer is diced, a plurality of driving chips 40 are formed. The channel conductors 04 are used for the connection between the first metal pads 01 on the first surface of the driving chip 40 and the circuit line layer 03 on the second surface of the driving chip 40. This design not only reduces the length of the connection lines but also avoids the occupation of the lead positions, greatly reducing the size of the light source device and solving the problem that the size of the existing light source body's package is large and cannot be reduced.

[0039] Figure 5a And Figure 5b are respectively schematic diagrams of the surface circuit structures of the driving chip 40 when at least one LED chip group 50 is one LED chip group 50 and multiple LED chip groups 50.

[0040] In this embodiment, a circuit line layer 03 and a plurality of second metal pads 02 are provided on the second surface of the driving chip 40. Through a plurality of channel conductors 04, a plurality of first metal pads 01 on the first surface of the driving chip 40 are conductively connected to the circuit line layer 03 on the second surface of the driving chip 40. A plurality of second metal pads 02 on the second surface of the driving chip 40 are connected to at least one LED chip group 50, thereby forming a brand-new miniaturized double-sided circuit driving chip 40.

[0041] In one embodiment, the aperture size of the through holes 502 provided in the scribe lanes 501 of the wafer is 50 - 200 μm to achieve a higher interconnection density.

[0042] In one embodiment, referring Figure 6a and Figure 6b As shown, the light source device further includes: a circuit substrate 10 and an outer encapsulation colloid 60. Specifically, the driving chip 40 is disposed on the upper surface of the circuit substrate 10 and the first surface of the driving chip 40 faces the upper surface of the circuit substrate 10. A plurality of electrical contacts are provided on the lower surface of the circuit substrate 10; the outer encapsulation colloid covers the driving chip 40 and the LED chip group 50 and is connected to the periphery of the upper surface of the circuit substrate 10.

[0043] In this embodiment, the circuit substrate 10 can be a printed circuit board (Printed Circuit Board), etc.; the LED chip group 50 is fixed directly above the driving chip 40 through a flip-chip process and forms a circuit conduction with the second metal pads 02, thereby forming a light source body integrated with the driving chip 40 and at least one LED chip group 50 with an extremely small package size, saving the space on the circuit substrate 10 reserved for placing the light source body and welding wires, greatly reducing the size of the packaged product, and thus making the size of the light source device more delicate and refined. Therefore, when the product is applied to the transparent display device market, it can meet the requirements of smaller pitch and high brightness display without affecting the transparency effect.

[0044] In one embodiment, the LED chip group 50 includes a red LED chip, a green LED chip, and a blue LED chip for combining to emit different colors of light.

[0045] In one embodiment, at least one LED chip group 50 is one LED chip group 50, and is located in the middle area of the second surface of the driving chip 40 together with a plurality of second metal pads 02; thereby forming a brand-new miniaturized double-sided circuit driving chip 40, greatly reducing the size of the light source device and solving the problem that the size of the existing light source body's package is large and cannot be reduced.

[0046] In one embodiment, at least one LED chip group 50 is a plurality of LED chip groups 50. The plurality of LED chip groups 50 and a plurality of second metal pads 02 are both distributed in the four corner regions of the second surface of the driving chip 40, making the light source device emit light more uniformly.

[0047] In one embodiment, a plurality of first metal pads 01 are distributed in the peripheral region of the first surface of the driving chip 40. This peripheral region is the edge position on the first surface close to the channel wire 04, realizing a double-sided circuit layer structure design with a more flexible method.

[0048] In this embodiment, by arranging the channel wire 04 on the four side surfaces of the driving chip 40, the internal space of the driving chip 40 is released. When packaging the light source body device, the single body size can be made smaller. Due to the flexible space of the channel wire 04 arranged on the four side surfaces of the driving chip 40, the driving chip 40 with the same single body area can also realize the layout of multiple groups of metal pads on the front and back. When packaging the light source body to the extreme in a certain space, the luminous brightness of the product can also be greatly improved.

[0049] In one embodiment, Figure 6a is a schematic diagram of one LED chip group 50. Figure 6b is a schematic diagram of multiple LED chip groups 50. The LED chip group 50 is connected to the corresponding plurality of second metal pads 02. Due to the adoption of multiple LED chip groups 50, the light-emitting effect is fully improved, making the emitted light cells uniform, the irradiation range wider, and the color more uniform.

[0050] In this embodiment, multiple LED chip groups 50 are arranged in an array, neatly arranged, and the light-emitting effect is better.

[0051] In addition, the embodiment of the present application also provides a preparation method for a light source device. Refer to Figure 7 as shown. The preparation method includes steps S10 to step S80.

[0052] In step S10, a driving chip wafer is manufactured. Referring to Figure 4 as shown, the driving chip wafer has a plurality of sub-blocks, a plurality of longitudinal cutting channels 501, and a plurality of transverse cutting channels 501. The plurality of transverse cutting channels 501 intersect perpendicularly with the plurality of longitudinal cutting channels 501 and divide the plurality of sub-blocks that are separated from each other.

[0053] In step S20, a plurality of through holes 502 are formed in a plurality of longitudinal cutting channels 501 and a plurality of transverse cutting channels 501, and conductive material is filled in the through holes 502 to form channel wires 04. In one embodiment, the channel wires 04 are processed by TSV technology, which can achieve electrical connection between different metal pads and miniaturize device integration. Since the cutting channels 501 are at the periphery of the sub-blocks of the driving chip wafer, fabricating the channel wires 04 in the cutting channels 501 will not affect the internal circuit layout of the sub-blocks, and no space needs to be reserved inside the sub-blocks for the channel wires 04, thus reducing the size of the light source device.

[0054] In step S30, a plurality of first metal pads 01 are disposed on the first surface of the sub-block, a circuit line layer 03 and a plurality of second metal pads 02 connecting the circuit line layer 03 are disposed on the second surface of the sub-block opposite to the first surface, and the channel wires 04 are connected to the first metal pads 01 and the circuit line layer 03 of two adjacent sub-blocks.

[0055] In step S40, the sub-blocks are cut along the median positions of the respective longitudinal cutting channels 501 and along the median positions of the respective transverse cutting channels 501 to form driving chips 40, so that a plurality of channel wires 04 exposed on the sides of each driving chip 40 are provided.

[0056] In step S50, a circuit carrier board is provided, a plurality of driving chips 40 are disposed on the upper surface of the circuit carrier board with the first surface of the driving chip 40 facing the upper surface of the circuit carrier board, and a plurality of electrical contacts are provided on the lower surface of the circuit carrier board.

[0057] In step S60, at least one LED chip group 50 is disposed on the second surface of the driving chip 40 and connected to the plurality of second metal pads 02 of the driving chip 40.

[0058] In step S70, an outer encapsulation layer is fabricated. The outer encapsulation layer covers a plurality of driving chips 40 and a plurality of LED chip groups 50 and connects the peripheral area of the upper surface of the circuit carrier board and the gap areas between the plurality of driving chips 40.

[0059] In step S80, the outer encapsulation layer and the circuit carrier board are cut and disconnected along the gaps between the plurality of driving chips 40 to obtain a plurality of light source devices. After the outer encapsulation layer is cut along the cutting channels, each outer encapsulation colloid 60 is formed, and after the circuit carrier board is cut along the cutting channels, each circuit substrate 10 is formed.

[0060] In one embodiment, the circuit line layer 03 and the plurality of second metal pads 02 on the second surface of the sub-block are formed by etching a metal layer, such as Figure 5a and Figure 5b the shown circuit structure.

[0061] In one embodiment, a plurality of first metal pads 01 of the sub-blocks are formed in a Redistribution Layer manner.

[0062] In this embodiment, adopting the Redistribution Layer manner increases the design flexibility, reduces the difficulty of layout and wiring, can also reduce the occupied area, enables a more compact arrangement, improves the circuit integration and performance; when packaging the light source body with extreme space optimization, the size of the light source device is reduced.

[0063] In this embodiment, the circuit line layer 03 and a plurality of second metal pads 02 are disposed on the second surface of the driving chip 40. The circuit line layer 03 is connected to the plurality of second metal pads 02. Through the circuit line layer 03, the circuit migration connection of the second metal pads 02 at unlimited positions can be realized, thereby reducing the size of the light source device. Moreover, the through-hole 502 is arranged in the scribe line 501 of the driving chip wafer, which can avoid reserving space for the through-hole inside the driving chip 40 and reduces the size of the light source device.

[0064] The light source device and its manufacturing method provided by the embodiments of the present application utilize the space of the scribe line of the wafer to realize the electrical connection design of the double-sided circuit layers for the driving chip 40. Compared with the limitation of the existing chip in making circuit design by avoiding the through-hole positions inside, the method of the embodiments of the present application is more flexible, enabling better denseness in its internal circuit design, thus releasing the area space of the driving chip 40. When packaging the light source body, the single body size can be made smaller. The driving chip 40 formed in this way is integrally packaged with at least one LED chip group. Under the same performance conditions, it can achieve miniaturization and meet the requirement of improving the luminous brightness of the product. Therefore, when the product is applied to the transparent display device market, it can meet the requirements of smaller pitch and high brightness display without affecting the transparency effect.

[0065] The present application also provides a display device, including: a transparent conductive plate and a plurality of light source devices as described in any of the above embodiments. The plurality of light source devices are arranged in an array on the transparent conductive plate, and a plurality of first metal pads 01 on the first surface of the driving chip 40 are electrically connected to the transparent conductive plate.

[0066] In the above embodiments, the descriptions of the various embodiments have their own emphases. For parts not detailed or recorded in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0067] The unit described as a separation component may or may not be physically separated. The component shown as a unit may or may not be a physical unit, that is, it may be located in one place or may be distributed across multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0068] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included within the protection scope of the present application.

Claims

1. A method for manufacturing a light source device, characterized in that, the manufacturing method includes: Manufacturing a driving chip wafer, the driving chip wafer having a plurality of sub-blocks, a plurality of longitudinal cutting channels and a plurality of transverse cutting channels, the plurality of transverse cutting channels intersecting perpendicularly with the plurality of longitudinal cutting channels and dividing the plurality of sub-blocks that are separated from each other; Forming a plurality of through holes in the plurality of longitudinal cutting channels and the plurality of transverse cutting channels, and filling conductive materials in the through holes to form channel wires; Providing a plurality of first metal pads on a first surface of the sub-block, providing a circuit line layer and a plurality of second metal pads connecting the circuit line layer on a second surface of the sub-block opposite to the first surface of the sub-block, and connecting the channel wires to the first metal pads and the circuit line layer of two adjacent sub-blocks; Cutting along the midline positions of the plurality of longitudinal cutting channels respectively and cutting along the midline positions of the plurality of transverse cutting channels respectively to form driving chips from the sub-blocks; Providing a circuit carrier board, disposing the plurality of driving chips on an upper surface of the circuit carrier board and the first surface of the driving chip facing the upper surface of the circuit carrier board, and providing a plurality of electrical contact points on a lower surface of the circuit carrier board; Disposing at least one LED chip group on the second surface of the driving chip and connecting the LED chip group to the plurality of second metal pads of the driving chip; Fabricating an outer encapsulation layer, the outer encapsulation layer covering the plurality of driving chips and the plurality of LED chip groups and connecting a peripheral area of the upper surface of the circuit carrier board and a gap area between the plurality of driving chips; and Cutting and disconnecting the outer encapsulation layer and the circuit carrier board along a gap between the plurality of driving chips to obtain a plurality of light source devices.

2. The manufacturing method according to claim 1, characterized in that, the circuit line layer and the plurality of second metal pads on the second surface of the sub-block are formed by an etching metal layer method.

3. The manufacturing method according to claim 1, characterized in that, the plurality of first metal pads of the sub-block are formed by a redistribution layer method.

4. The manufacturing method according to claim 1, characterized in that, the LED chip group includes a red LED chip, a green LED chip and a blue LED chip.

5. The manufacturing method according to claim 1, characterized in that, the LED chip group and the plurality of second metal pads are both located in a middle area of the second surface of the driving chip.

6. The manufacturing method according to claim 1, characterized in that, the plurality of LED chip groups and the plurality of second metal pads are both distributed in four corner areas of the second surface of the driving chip.

7. The manufacturing method according to claim 1, characterized in that, the plurality of first metal pads are distributed in a peripheral area of the first surface of the driving chip.

8. A display device, characterized in that, comprising: A transparent conductive plate and a plurality of the light source devices prepared by the preparation method according to any one of claims 1-7, wherein the plurality of the light source devices are arranged in an array on the transparent conductive plate, and a plurality of the first metal pads on the first surface of the driving chip are electrically connected to the transparent conductive plate.

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