A high contrast LED display device and its manufacturing method and module

Abstract

The present invention discloses a high-contrast LED display device and a manufacturing method and module thereof, wherein the device comprises: a bracket, comprising a substrate and a circuit line arranged on the substrate, the circuit line comprising a front circuit line and a back circuit line, and a solid crystal area is arranged on the front circuit line; at least one local light-emitting chip is arranged on the solid crystal area, comprising a local light-emitting area and a light-absorbing area, and the local light-emitting area is arranged on the edge of the local light-emitting chip; and a packaging glue is used to wrap the local light-emitting chip, and the packaging glue is a transparent packaging glue. The present invention arranges a light-absorbing area outside the local light-emitting area of ​​the local light-emitting chip, and can form a total light-emitting area by bringing multiple local light-emitting areas close together, thereby greatly concentrating the light-emitting parts and improving the contrast of the LED display device. The present invention can be widely used in the technical field of LED display devices.

Description

Technical Field

[0001] The present invention relates to the technical field of LED display devices, and in particular to a high-contrast LED display device and a manufacturing method and module thereof. Background Art

[0002] As display application technology continues to improve, traditional display product technology has gradually reached the top, and small-pitch products have become the main technology expansion space in the future; in order to replace high-definition display products such as LCD and DLP, improving the contrast of small-pitch LED display screens has become the main means for LED packaging manufacturers to improve product competitiveness. At present, the display packaging devices on the market mainly have the problems of low contrast and insufficient concentration of the light-emitting part. The functional area cavity of the common LED packaging devices on the market is large, and the surface area of ​​the top of the functional area cavity is large. After sealing with white packaging glue, the white color of the product surface accounts for a large proportion, and the contrast is not high after the screen is on. If a black agent is added to the packaging glue, it will have a greater impact on the brightness of the product and cannot meet the application requirements of the terminal market. Summary of the invention

[0003] In order to solve at least one of the technical problems existing in the prior art to a certain extent, the object of the present invention is to provide a high-contrast LED display device and a manufacturing method and module thereof.

[0004] The technical solution adopted by the present invention is:

[0005] A high contrast LED display device, comprising:

[0006] A bracket, comprising a substrate and a circuit line arranged on the substrate, wherein the circuit line comprises a front circuit line and a back circuit line, and a crystal bonding area is arranged on the front circuit line;

[0007] At least one local light-emitting chip is disposed on the crystal-fixing area, comprising a local light-emitting area and a light-absorbing area, wherein the local light-emitting area is disposed at an edge position of the local light-emitting chip;

[0008] The packaging glue is used to wrap the local light-emitting chip, and the packaging glue is a transparent packaging glue.

[0009] Furthermore, three local light-emitting chips are arranged on the solid crystal area to form an RGB LED chipset, and the light-emitting areas corresponding to the three local light-emitting chips are closely arranged to form a concentrated light-emitting area.

[0010] Furthermore, the concentrated light emitting area is located at the center of the substrate.

[0011] Furthermore, the interval between the light-emitting areas corresponding to the three partial light-emitting chips is less than 300 μm.

[0012] Furthermore, the concentrated light emitting area is surrounded by a light absorbing area, and the light absorbing area is made of one or a mixture of carbon acrylic resin, epoxy resin, polyurethane resin, silicone resin and cyanoacrylate resin.

[0013] Furthermore, the local light-emitting chip adopts a flip-chip structure, a vertical structure or a face-up structure.

[0014] Furthermore, a black ink layer is provided on the surface of the front circuit line except for the crystal bonding area.

[0015] Furthermore, a conductive hole is provided on the substrate for connecting the front circuit line and the back circuit line.

[0016] Furthermore, a bonding adhesive is provided between the local light-emitting chip and the bracket to fix the chip or conduct electricity.

[0017] Furthermore, the substrate has a thickness of 0.1-2 mm and a surface color of black.

[0018] Another technical solution adopted by the present invention is:

[0019] A high-contrast multi-pixel LED display device packaging module is composed of a plurality of LED display devices. The LED display device is implemented by using the high-contrast LED display device described above.

[0020] Another technical solution adopted by the present invention is:

[0021] A method for manufacturing a high contrast LED display device comprises the following steps:

[0022] Making local light-emitting chips: fixing the whole chip, preparing local light-emitting areas, wherein the local light-emitting areas are arranged at the edge of a single chip, and cutting the whole chip into single chips by scribing to obtain local light-emitting chips;

[0023] Bonding: transferring the local light-emitting chip to the bonding area;

[0024] Sealing glue: coating the local light-emitting chip and the substrate with sealing glue, wherein the sealing glue is a transparent sealing glue.

[0025] The beneficial effects of the present invention are as follows: the present invention sets a light absorption area outside the local light-emitting area of ​​the local light-emitting chip, and can closely bring multiple local light-emitting areas together to form a total light-emitting area, which greatly concentrates the light-emitting parts and improves the contrast of the LED display device. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the embodiments of the present invention or the drawings of related technical solutions in the prior art are introduced below. It should be understood that the drawings introduced below are only for the convenience of clearly describing some embodiments of the technical solutions of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 is a schematic diagram of a local light-emitting chip in an embodiment of the present invention;

[0028] Figure 2 It is a front schematic diagram of a high-contrast LED flip-chip structure display device (without the packaging glue) in an embodiment of the present invention;

[0029] Figure 3 It is a front schematic diagram of a high-contrast LED vertical structure display device (without packaging glue) in an embodiment of the present invention;

[0030] Figure 4 Schematic diagram of a back electrode of a high contrast LED display device in an embodiment of the present invention;

[0031] Figure 5 It is a front schematic diagram of a high-contrast multi-pixel LED display device packaging module (with the packaging glue removed) in an embodiment of the present invention.

[0032] Figure 6 This is a schematic diagram of the back electrode of a high-contrast multi-pixel LED display device package module in an embodiment of the present invention;

[0033] Figure 7 A front schematic diagram of a high-contrast LED flip-chip structure display device (without the packaging glue) in an embodiment of the present invention;

[0034] Figure 8 A schematic side view of a high contrast LED display device (with packaging adhesive) in an embodiment of the present invention. DETAILED DESCRIPTION

[0035] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and are not to be construed as limitations of the present invention. For the step numbers in the following embodiments, they are only provided for the convenience of explanation, and the order between the steps is not limited in any way, and the execution order of each step in the embodiment can be adaptively adjusted according to the understanding of those skilled in the art.

[0036] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0037] In the description of the present invention, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood as not including the number itself, and "above", "below", "within" etc. are understood as including the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0038] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0039] like Figure 1 and Figure 8 As shown, a single local light-emitting chip is prepared. The preparation of the local light-emitting area can be achieved by etching to remove the light-emitting layer, covering the light-absorbing material, or a combination of the above two methods. The light-emitting area 201 of the local light-emitting chip is located in a local area of ​​the chip, such as a corner or the center of the edge. Except for the local light-emitting area and the welding wire area (vertical or upright structure chips have it), other areas are provided with a light-absorbing area 202, and other areas except the local light-emitting area do not have a light-emitting function. The local light-emitting chip can be a flip-chip, vertical or upright structure chip; a single group or multiple groups of RGB LED chips can be set, but at least one group. The local light-emitting areas of the chips in the group can be closely arranged so that the light-emitting area is located in the center of the substrate to form a concentrated light-emitting area. Among them, Figure 1 203 is the pad pin of the local light-emitting chip. Black and white display can be realized by using a single local light-emitting chip, and color display can be realized by using an RGB LED chipset.

[0040] like Figure 2 The figure shows a schematic diagram of the bottom surface of the substrate. When the substrate is provided with a single group of RGB LED chips, four solder pads can be provided on the bottom surface of the substrate for connecting with other circuits.

[0041] like Figures 3 to 5The high-contrast LED display device shown includes a bracket 1, a local light-emitting chip 2 and a packaging glue 3; the bracket 1 includes a substrate 101, on which a circuit line is arranged, and the circuit line includes two parts: a front circuit line located on the front side of the substrate and a back circuit line on the back side; a black ink layer 102 is arranged on the upper surface of the front circuit line except for the solid crystal area; a conductive hole is arranged on the substrate 101 for connecting the front circuit line and the back circuit line; the local light-emitting chip 2 can be a flip-chip structure, a vertical structure or a face-up structure, and the chip 2 has a local light-emitting area 201, which is arranged at the edge position of the local light-emitting chip 2 (such as a corner or the center of the edge); the local light-emitting chip 2 is provided with a light absorption area 202 in addition to the local light-emitting area 201; a solid crystal glue is also arranged between the local light-emitting chip 2 and the bracket 1 to fix the chip or conduct electricity. Among them, Figure 3 103 in the figure is the wire bonding area of ​​the substrate. Figure 4 104 is the soldering pin at the bottom of the substrate.

[0042] The local light-emitting chip 2 can be provided with a single group or multiple groups of RGB LED chips, but at least one group. The local light-emitting areas of the one or more groups of chips are closely arranged, with a spacing of less than 300 μm, and are located in the center of the substrate 101 to form a concentrated light-emitting area.

[0043] The substrate 101 has a thickness of 0.1-2 mm and is made of one or a mixture of aluminum substrate, copper substrate, and ceramic substrate. The front circuit lines of the substrate 101, except for the die-bonding area and the wire bonding area, are all covered with black ink. The black ink can be UV curable ink, the ink can be character ink or solder resist ink, and the thickness of the ink layer is 5um-150um.

[0044] The manufacturing method of the high contrast LED display device is implemented by the following technical method:

[0045] A. Making partial light-emitting chips: Fix the whole chip, and use etching to remove the light-emitting layer, cover the light-absorbing material, or a combination of the above two methods to achieve the preparation of the partial light-emitting area. The partial light-emitting area can be set in a local area of ​​a single chip, such as a corner or the center of an edge. Finally, the whole chip is cut into individual chips by scribing, and the prepared partial light-emitting chip can be obtained.

[0046] B. Bonding: Set bonding glue in the bonding area of ​​the substrate, and transfer the manufactured local light-emitting chip to the bonding area. Arrange the RGB local light-emitting chips closely with a spacing of less than 300 μm. They can be set in the center or other areas of the substrate to form a concentrated light-emitting area.

[0047] C. Wire bonding: The chip with a local light-emitting area can be a flip-chip, vertical or upright structure. If it is a flip-chip structure chip, no wire bonding is required. If it is a vertical or upright structure chip, after the chip is fixed on the substrate, one end of the metal lead is connected to the electrode of the local light-emitting chip, and the other end is welded to the wire bonding area on one side of the substrate. After welding, the area of ​​the solder ball in the top electrode is about 30% to 100% of the area of ​​the welding nozzle, and the welding temperature needs to be at least 100°C.

[0048] D. Sealing glue: The sealing glue is a transparent sealing glue with a transmittance of 85-99%. The sealing glue can be applied on the prepared partial light-emitting chip and substrate by coating, printing, etc.

[0049] Embodiment 1:

[0050] like Figure 3 and Figure 7 As shown, a single group of RGB flip-chip structure LED local light-emitting chips are respectively fixed to the substrate solid crystal area, and the light-emitting areas of the local light-emitting chips are respectively located at the edge or center of the chip, and the local RGB light-emitting areas are closely arranged with a spacing of less than 300μm, and the concentrated light-emitting area formed is located at the center of the substrate. Except for the light-emitting area, the other areas of the RGB chip (the chip structure is a flip-chip structure, and there is no wire bonding area) are all provided with light-absorbing materials to form a light-absorbing area, and do not have the ability to emit light. Except for the solid crystal area, the front circuit of the substrate is covered with black ink.

[0051] Embodiment 2:

[0052] like Figure 4 As shown, a single group of RGB vertical structure LED local light-emitting chips are respectively fixed to the solid crystal area of ​​the substrate, and the light-emitting areas of the local light-emitting chips are respectively located at the edge or center of the chip, and the local RGB light-emitting areas are closely arranged with a spacing of less than 300μm, and the concentrated light-emitting area formed is located in the center of the substrate. The wire bonding area of ​​the vertical chip is connected to the wire bonding area on the substrate with gold wire. Except for the light-emitting area and the wire bonding area, the other areas of the RGB chip are provided with light-absorbing materials to form a light-absorbing area, and do not have the ability to emit light. Except for the solid crystal area and the wire bonding area, the front circuit of the substrate is covered with black ink.

[0053] Embodiment three:

[0054] like Figure 5As shown, multiple RGB LED chip groups are respectively fixed on the die-bonding area of ​​the substrate to form a multi-pixel high-contrast LED display device integrated packaging module. The pitch of the local light-emitting chips in each RGB LED chip group is less than 300μm to form a small-pitch display integrated packaging module. Multiple pixels are integrated on the same substrate for packaging. Electrodes are arranged behind the integrated packaging module. A light absorption area is arranged outside the local light-emitting area of ​​each group of chips in each pixel, and multiple local light-emitting areas are closely placed to form a total light-emitting area, which greatly concentrates the light-emitting parts and improves the contrast of the LED display device. Figure 6 Schematic diagram of the back electrodes of a multi-pixel LED display device packaging module.

[0055] In some selectable embodiments, the function / operation mentioned in the block diagram may not occur in the order mentioned in the operation diagram. For example, depending on the function / operation involved, the two boxes shown in succession can actually be executed substantially simultaneously or the boxes can sometimes be executed in reverse order. In addition, the embodiment presented and described in the flow chart of the present invention is provided by way of example, for the purpose of providing a more comprehensive understanding of technology. The disclosed method is not limited to the operation and logic flow presented herein. Selectable embodiments are expected, wherein the order of various operations is changed and the sub-operation of a part for which is described as a larger operation is performed independently.

[0056] In addition, although the present invention is described in the context of functional modules, it should be understood that, unless otherwise specified, one or more of the functions and / or features described may be integrated into a single physical device and / or software module, or one or more functions and / or features may be implemented in separate physical devices or software modules. It is also understood that a detailed discussion of the actual implementation of each module is unnecessary for understanding the present invention. More specifically, in view of the properties, functions, and internal relationships of the various functional modules in the device disclosed herein, the actual implementation of the module will be understood within the conventional skills of the engineer. Therefore, those skilled in the art can implement the present invention set forth in the claims without excessive experimentation using ordinary techniques. It is also understood that the specific concepts disclosed are merely illustrative and are not intended to limit the scope of the present invention, which is determined by the full scope of the appended claims and their equivalents.

[0057] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program codes.

[0058] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0059] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0060] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0061] In the above description of this specification, the description with reference to the terms "one embodiment / example", "another embodiment / example" or "certain embodiments / examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0062] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

[0063] The above is a specific description of the preferred implementation of the present invention, but the present invention is not limited to the above embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A high contrast LED display device, characterized in that: include: A bracket, comprising a substrate and a circuit line arranged on the substrate, wherein the circuit line comprises a front circuit line and a back circuit line, and a crystal bonding area is arranged on the front circuit line; Three local light-emitting chips are arranged on the solid crystal area to form an RGB LED chip group, wherein the local light-emitting chip includes a local light-emitting area and a light-absorbing area, and the local light-emitting area is arranged at the edge of the local light-emitting chip; the light-emitting areas corresponding to the three local light-emitting chips are closely arranged to form a concentrated light-emitting area; Packaging glue, used to wrap the local light-emitting chip, the packaging glue is a transparent packaging glue; The concentrated light emitting area is located at the center of the substrate; The concentrated light emitting area is surrounded by a light absorbing area, and the light absorbing area is made of one or a mixture of carbon acrylic resin, epoxy resin, polyurethane resin, silicone resin and cyanoacrylate resin.

2. A high contrast LED display device according to claim 1, characterized in that: The interval between the light-emitting areas corresponding to the three partial light-emitting chips is less than 300 μm.

3. A high contrast LED display device according to claim 1, characterized in that: A black ink layer is arranged on the surface of the front circuit line except the crystal bonding area.

4. A high contrast LED display device according to claim 1, characterized in that: The substrate is provided with a conductive hole for connecting the front circuit line and the back circuit line.

5. A high contrast LED display device according to claim 1, characterized in that: A bonding adhesive is also provided between the local light-emitting chip and the bracket to fix the chip or conduct electricity.

6. A high-contrast multi-pixel LED display device packaging module, characterized in that: The device is composed of a plurality of LED display devices, wherein the LED display device is implemented by a high-contrast LED display device as described in any one of claims 1 to 5.

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