MIP chip structure and display panel

Abstract

The utility model relates to the technical field of semiconductor display, in particular to an MIP chip structure and a display panel, and after the MIP chip structures are manufactured, a plurality of MIP chip structures are bonded on a driving substrate to form the final display panel. The MIP chip structure comprises a circuit backboard which is provided with a first electrode bonding pad and a plurality of independent second electrode bonding pads; the plurality of light-emitting chips are chips with vertical structures and emit light rays with the same color, the first electrodes of the light-emitting chips are communicated with the first electrode bonding pads, and the second electrodes of the light-emitting chips are correspondingly bonded with the second electrode bonding pads respectively, namely, the plurality of light-emitting chips are directly bonded with the circuit backboard after being grown on the same epitaxial wafer; a huge transfer process flow is greatly reduced; in addition, a color conversion layer is arranged above the plurality of light-emitting chips so as to realize color conversion of light emitted by the light-emitting chips.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor display, in particular to a MIP chip structure and a display panel. Background Art

[0002] As people's lives become smarter, display screens are increasingly being used in all aspects of life. MLED (including mini LED & Micro LED) displays have attracted widespread attention in the display industry due to their excellent contrast and brightness. In order to simplify the production of light boards, facilitate rework and repair, and improve product yield, many MLED manufacturers have proposed and used multiple chips to first be mounted on a small carrier substrate to make a MIP (Micro LED in Package) module, and then transfer the MIP module as a unit to the final light board.

[0003] The conventional production method is to produce MIP by mass transfer, that is, to transfer the three flip-chip MLED chips of RGB to the MIP substrate. Then the MIP production is realized by packaging and cutting. Since the transfer of a large number of chips requires high transfer capacity and yield, the transfer yield of this process is low and the cost is high. Utility Model Content

[0004] The purpose of the utility model is to provide a MIP chip structure and a display panel, simplifying the manufacturing process and improving the yield, so as to achieve the effect of reducing costs.

[0005] The utility model is achieved in this way:

[0006] In a first aspect, a MIP chip structure is provided, the MIP chip structure comprising: a circuit backplane, on which a first electrode pad and a plurality of independent second electrode pads are disposed; a plurality of light-emitting chips, the plurality of light-emitting chips are all vertical structure chips and all emit light of the same color, the first electrodes of the plurality of light-emitting chips are all connected to the first electrode pad, and the second electrodes of the plurality of light-emitting chips are respectively bonded to a corresponding second electrode pad; and a color conversion layer, the color conversion layers are respectively disposed above the plurality of light-emitting chips to convert the color of the light emitted by the light-emitting chips.

[0007] By transferring and bonding the vertical structure light-emitting chips emitting the same color of light to the circuit backplane, that is, directly using the wafer bonding method to bond the light-emitting chips on the entire wafer to the circuit backplane, compared with the method of transferring RGB light-emitting chips three times respectively, this one-time transfer method greatly simplifies the mass transfer process; and then by setting a color conversion layer, composite light emission is achieved.

[0008] Furthermore, the MIP chip structure further includes an insulating layer, which is entirely covered on the circuit backplane and is patterned to expose the upper surfaces of the first electrode pad and a plurality of independent second electrode pads.

[0009] By setting an insulating layer, on the one hand, the circuit backplane is protected, and on the other hand, a short circuit between the first electrode pad and the second electrode pad can be prevented in the subsequent process technology; at the same time, patterning the insulating layer also facilitates the subsequent electrical connection between the first electrode pad and the second electrode pad and the light-emitting chip.

[0010] Furthermore, the MIP chip structure also includes a transparent conductive layer. When the second electrodes of the multiple light-emitting chips are each bonded to a corresponding second electrode pad, the transparent conductive layer is used to cover the outer side surfaces of the multiple light-emitting chips and the upper surface of the first electrode pad exposed by the insulating layer, so as to connect the first electrodes of the multiple light-emitting chips to the first electrode pad.

[0011] The first electrodes of the plurality of light-emitting chips are connected to the first electrode pads on the circuit backplane through the transparent conductive layer, so that a common electrode setting is achieved for all the light-emitting chips.

[0012] Furthermore, the MIP chip structure further includes a black blocking layer, and the black blocking layer fills the gaps between the plurality of light-emitting chips.

[0013] The display contrast is improved by setting a black barrier layer between the light-emitting chips.

[0014] Furthermore, the MIP chip structure further includes a packaging protection layer, which is formed above the color conversion layer and is transparent.

[0015] The packaging protection layer is provided to protect the entire MIP chip structure, and at the same time, it is transparent and does not affect the overall light emitting effect.

[0016] Furthermore, the color conversion layer includes a red light conversion layer and a green light conversion layer, and is respectively arranged above different light emitting chips after being patterned to perform color conversion on light emitted from the light emitting chips.

[0017] By arranging the color conversion layers above different light-emitting chips, the light emitted by different light-emitting chips can be converted, thereby achieving three-color mixed light emission.

[0018] In a second aspect, a display panel includes a driving substrate and a plurality of the MIP chip structures, wherein the MIP chip structures are bonded to the driving substrate.

[0019] Compared with the prior art, the utility model has the following beneficial effects: the utility model provides a MIP chip structure and a display panel. After the MIP chip structure is manufactured, multiple MIP chip structures are bonded to a driving substrate to form a final display panel. The MIP chip structure includes a circuit backplane, on which a first electrode pad and multiple independent second electrode pads are arranged; multiple light-emitting chips, all of which are vertical structure chips and emit light of the same color, and their first electrodes are connected to the first electrode pad, and the second electrodes are respectively bonded to a corresponding second electrode pad, that is, the multiple light-emitting chips are grown on the same epitaxial sheet, and the epitaxial sheet is directly bonded to the circuit backplane, which greatly reduces the mass transfer process; in addition, a color conversion layer is also arranged above the multiple light-emitting chips to achieve color conversion of the light emitted by the light-emitting chips.

[0020] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to make the purpose, technical scheme and advantages of the embodiment of the utility model clearer, the technical scheme in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, rather than all the embodiments. The components of the embodiment of the utility model generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiment of the utility model provided in the drawings is not intended to limit the scope of the utility model for protection, but merely represents the selected embodiment of the utility model. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the utility model.

[0022] Figure 1 The schematic diagram shows a structure of a MIP chip structure provided by the utility model.

[0023] Figure 2 A schematic diagram of circuit distribution on a circuit backplane provided by the utility model is shown.

[0024] Figure 3 A schematic diagram of circuit distribution on another circuit backplane provided by the utility model is shown.

[0025] Diagram:

[0026] 100-MIP chip structure; 110-circuit backplane; 111-first electrode pad; 112-second electrode pad; 113-insulating layer; 114-transparent conductive layer; 115-black blocking layer; 116-encapsulation protection layer; 117-first electrode pad via hole; 118-second electrode pad via hole; 120-light-emitting chip; 130-color conversion layer; 131-red light conversion layer; 132-green light conversion layer. DETAILED DESCRIPTION

[0027] The technical scheme in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, rather than all the embodiments. The components of the embodiment of the utility model generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiment of the utility model provided in the drawings is not intended to limit the scope of the utility model claimed for protection, but merely represents the selected embodiment of the utility model. Based on the embodiment of the utility model, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the utility model.

[0028] Please refer to Figure 1 , is a schematic diagram of a MIP chip structure 100 provided in an embodiment of the present utility model, and the MIP chip structure 100 includes:

[0029] The circuit back plate 110 is provided with a first electrode pad 111 and a plurality of independent second electrode pads 112. The first electrode pad 111 and the second electrode pad 112 are respectively used to be electrically connected to the two ends of the light emitting chip 120. For further information, please refer to Figure 2 , is a schematic diagram of circuit distribution on a circuit backplane 110 provided by an embodiment of the utility model, wherein, on the upper surface of the circuit backplane 110, the first electrode pad 111 is a ring-shaped structure designed in a circle, so as to achieve the effect of anti-ESD (static electricity); the second electrode pad 112 is a pad structure arranged at a certain distance to avoid short circuits between each other. On the lower surface of the circuit backplane 110, the first electrode pad 111 on the upper surface is connected to the first electrode pad 111 on the lower surface through the first electrode pad conduction hole 117, and the second electrode pad 112 on the upper surface is connected to the second electrode pad 112 on the lower surface through the second electrode pad conduction hole 118.

[0030] It should be noted that, on the one hand, the first electrode pad via hole 117 and the second electrode pad via hole 118 are filled with conductive materials, such as metal materials such as iron and copper, so that the circuits on the upper and lower surfaces of the circuit backplane 110 can be connected. On the other hand, the first electrode pad 111 and the multiple independent second electrode pads 112 arranged on the upper surface of the circuit backplane 110 are used to be bonded and connected to the multiple light-emitting chips 120 respectively to achieve power supply; the first electrode pad 111 and the multiple second electrode pads 112 arranged on the lower surface of the circuit backplane 110 are used to be bonded and connected to the driving substrate after the MIP chip structure 100 is packaged, so as to finally form a display panel.

[0031] Furthermore, in order to facilitate the bonding of the MIP chip structure 100 to the driving substrate, the first electrode pad 111 and the multiple independent second electrode pads 112 arranged on the lower surface of the circuit backplane 110 can have a larger pad area than the first electrode pad 111 and the multiple independent second electrode pads 112 arranged on the upper surface, while ensuring a certain spacing distance to prevent short circuit, so that the MIP chip structure 100 has a larger contact area with the driving substrate and a higher bonding yield.

[0032] It should be noted that in the embodiment of the utility model, the MIP chip structure 100 is illustrated by way of example as having three light-emitting chips 120, and the number of electrode pads arranged on the circuit backplane 110 is also arranged accordingly according to the number of the light-emitting chips 120. It is easy to understand that the MIP chip structure 100 can also include more light-emitting chips 120 according to actual needs, such as four or five.

[0033] For further information, please refer to Figure 3 , is another schematic diagram of circuit distribution on the circuit backplane 110 provided by an embodiment of the utility model. On the upper surface of the circuit backplane 110, the multiple independent second electrode pads 112 are designed to the edge of the circuit backplane 110 to reduce the difficulty of making the via hole; and then a position for bonding with the light emitting chip 120 is reserved by patterning metal wires. Figure 3 In the figure, the first electrode pad 111 on the upper surface of the circuit backplane 110 is connected to the first electrode pad 111 on the lower surface through the first electrode pad via hole 117; the second electrode pad 112 on the upper surface of the circuit backplane 110 is connected to the second electrode pad 112 on the lower surface through the second electrode pad via hole 118.

[0034] from Figure 3Comparing the circuits on the upper and lower surfaces of the circuit backplane 110, it can be seen that the second electrode pads 112 on the lower surface are all distributed at the edge of the circuit backplane 110, which can effectively reduce the difficulty of making the through-holes and facilitate the conduction of the circuits on the upper and lower surfaces; at the same time, the spacing between the multiple electrode pads on the lower surface is large, which is also convenient for the subsequent MIP chip structure 100 to be bonded to the driving substrate without short circuit, thereby improving the production yield. At the same time, in order to facilitate bonding with the light-emitting chip 120, the circuit of the second electrode pad 112 on the upper surface of the circuit backplane 110 is extended by patterned metal wires to facilitate one-to-one bonding with the electrodes of the light-emitting chip 120, while the first electrode pad 111 is only required to achieve conduction between the upper and lower surfaces.

[0035] Please continue to refer to Figure 1 , the MIP chip structure 100 also includes a plurality of light-emitting chips 120, which are all vertical structure chips, that is, the first electrode and the second electrode of the light-emitting chip 120 are respectively located on the upper and lower sides, rather than on the same side of the light-emitting chip 120. At the same time, the plurality of light-emitting chips 120 all emit light of the same color, that is, the plurality of light-emitting chips 120 are grown on the same epitaxial (wafer) substrate, and can be directly transferred and bonded to the circuit backplane 110 by wafer bonding. Compared with the current MIP chip using the RGB three-color chip to be transferred and bonded to the circuit backplane three times, the method adopted in this solution has fewer transfer times, higher yield and lower cost. The first electrodes of the plurality of light-emitting chips 120 are all connected to the first electrode pad 111 to realize the common electrode setting, and the second electrodes thereof are respectively bonded to a corresponding second electrode pad 112 to realize independent driving.

[0036] In addition, the MIP chip structure 100 further includes a color conversion layer 130, which is respectively disposed above the plurality of light-emitting chips 120 to convert the color of the light emitted by the light-emitting chip 120. If the light-emitting chip 120 is a blue light chip that emits blue light, the color conversion layer 130 can be patterned multiple times to form a red light conversion layer 131 and a green light conversion layer 132 on different light-emitting chips 120, respectively, to convert the corresponding blue light emitted into red light and green light, respectively, so that the MIP chip structure 100 can emit white light in a mixed manner. It is easy to understand that the color conversion layer 130 can be a quantum dot material, or it can be one or a combination of fluorescent materials such as nitrides or silicates.

[0037] It can be seen that the present solution designs a vertically structured light-emitting chip 120, which is bonded to the circuit backplane 110 by wafer bonding, and then forms a color conversion layer 130 on multiple light-emitting chips 120 to achieve composite light emission, thereby reducing the transfer process, improving the production yield, and thus reducing costs.

[0038] Furthermore, the MIP chip structure 100 provided in the present solution further includes an insulating layer 113, which is entirely covered on the circuit backplane 110, and after patterning, exposes the upper surfaces of the first electrode pad 111 and the plurality of second electrode pads 112, so as to facilitate subsequent bonding with the light-emitting chip 120. The insulating layer 113 can be made of materials such as transparent silicon oxide, or can be one or more insulating materials such as aluminum oxide with a high refractive index or fluoride or silicon oxide with a reflective effect, and is mainly used to protect the circuit backplane 110, and can effectively prevent the first electrode pad 111 and the plurality of second electrode pads 112 from short-circuiting each other in subsequent processes.

[0039] The MIP chip structure 100 further includes a transparent conductive layer 114. When the second electrodes of the plurality of light-emitting chips 120 are respectively bonded to a second electrode pad 112, the transparent conductive layer 114 is entirely covered on the outer side surfaces of the plurality of light-emitting chips 120 and the upper surface of the first electrode pad 111 exposed by the insulating layer 113, so that the first electrodes of the plurality of light-emitting chips 120 are all connected to the first electrode pad 111 to achieve common electrode connection. The transparent conductive layer 114 may be, but is not limited to, indium tin oxide.

[0040] The MIP chip structure 100 further includes a black barrier layer 115 which is filled between the gaps between the plurality of light emitting chips 120 to reduce the reflection of the circuit metal on the circuit backplane 110 to the ambient light and improve the visual effect.

[0041] The MIP chip structure 100 also includes a packaging protection layer 116. After the black blocking layer 115 is formed between the light-emitting chips 120 and the color conversion layer 130 is formed above the plurality of light-emitting chips 120, the packaging protection layer 116 is used to package and protect the overall structure. In order not to affect the light-emitting effect of the overall MIP chip structure 100, the packaging protection layer 116 is transparent.

[0042] In addition, an embodiment of the utility model further provides a display panel, which includes a driving substrate and multiple MIP chip structures 100 as described above. The multiple MIP chip structures 100 are bonded to the driving substrate through the first electrode pad 111 and multiple second electrode pads 112 on the lower surface of the circuit backplane 110 thereof. The display panel can be but is not limited to a computer display screen, a TV display screen, a large outdoor display screen, a mobile phone screen, etc.

[0043] In summary, the utility model provides a MIP chip structure and a display panel. After the MIP chip structure is manufactured, multiple MIP chip structures are bonded to a driving substrate to form a final display panel. The MIP chip structure includes a circuit backplane, on which a first electrode pad and multiple independent second electrode pads are arranged; multiple light-emitting chips, the multiple light-emitting chips are all vertical structure chips and all emit light of the same color, the first electrodes are all connected to the first electrode pad, and the second electrodes are each bonded to a corresponding second electrode pad, that is, the multiple light-emitting chips are grown on the same piece of epitaxy, and the epitaxy is directly bonded to the circuit backplane, which greatly reduces the mass transfer process; in addition, a color conversion layer is also arranged above the multiple light-emitting chips to achieve color conversion of the light emitted by the light-emitting chips.

[0044] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0046] In the description of the present utility model, it should be noted that the terms "upper", "lower", "left", "right", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are directions or positional relationships in which the utility model product is usually placed when in use. They are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present utility model. The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. For those skilled in the art, the present utility model may have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present utility model shall be included in the scope of protection of the present utility model.

Claims

1. A MIP chip structure, characterized in that: The MIP chip structure includes: A circuit back plate, wherein a first electrode pad and a plurality of independent second electrode pads are arranged on the circuit back plate; A plurality of light-emitting chips, wherein the plurality of light-emitting chips are vertical structure chips and emit light of the same color, the first electrodes of the plurality of light-emitting chips are connected to the first electrode pad, and the second electrodes of the plurality of light-emitting chips are respectively bonded to a corresponding second electrode pad; Color conversion layers are respectively disposed above the plurality of light emitting chips to convert the colors of the light emitted by the light emitting chips.

2. The MIP chip structure according to claim 1, characterized in that: The MIP chip structure further includes an insulating layer, which is entirely covered on the circuit backplane and is patterned to expose the upper surfaces of the first electrode pad and a plurality of independent second electrode pads.

3. The MIP chip structure according to claim 2, characterized in that: The MIP chip structure further includes a transparent conductive layer, After the second electrodes of the multiple light-emitting chips are each bonded to a corresponding second electrode pad, the transparent conductive layer is used to cover the outer side surfaces of the multiple light-emitting chips and the upper surface of the first electrode pad exposed by the insulating layer, so as to connect the first electrodes of the multiple light-emitting chips to the first electrode pad.

4. The MIP chip structure according to claim 1, characterized in that: The MIP chip structure further includes a black blocking layer, and the black blocking layer fills the gaps between the plurality of light-emitting chips.

5. The MIP chip structure according to claim 1, characterized in that: The MIP chip structure further includes a packaging protection layer, which is formed above the color conversion layer and is transparent.

6. The MIP chip structure according to claim 1, characterized in that: The plurality of light emitting chips all emit blue light.

7. The MIP chip structure according to claim 6, characterized in that: The color conversion layer includes a red light conversion layer and a green light conversion layer, and is respectively arranged above different light emitting chips after being patterned to perform color conversion on light emitted from the light emitting chips.

8. A display panel, characterized in that: The display panel comprises a driving substrate and a plurality of MIP chip structures according to any one of claims 1 to 7, wherein the MIP chip structures are bonded to the driving substrate.

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