Pixel display unit, display panel and manufacturing method

Abstract

The invention provides a pixel display unit, a display panel and a manufacturing method, the pixel display unit comprises a pixel light-emitting array, a driving chip and an intermediate layer, the pixel light-emitting array is composed of a light-emitting device array and a substrate bearing the light-emitting device array, the driving chip is composed of a pixel circuit array of a driving circuit and a substrate bearing the pixel circuit array, and the intermediate layer is composed of a light-emitting device array, a light-emitting device array and a substrate bearing the light-emitting device array. The intermediate layer serves as a physical carrier of the pixel light-emitting array and the driving chip and is provided with a plurality of conductive channels to achieve electrical connection between pixels of the light-emitting array and the pixel circuit array, and the pixel light-emitting array and the pixel circuit array have a one-to-one correspondence relation between pixel points. The driving chip and the pixel light-emitting array are bonded to the intermediate layer and are electrically connected through the conductive channel, so that the pixel circuit array in the driving chip cannot be matched with the pixel pitch of the pixel light-emitting array, and the manufacturing process of the driving chip can be prevented from being influenced by the pixel light-emitting array; the manufacturing process difficulty of the pixel display unit is reduced, and the process operation is simplified.

Description

Technical Field

[0001] This application relates to the field of display technologies, and particularly to a pixel display unit, a display panel, and a manufacturing method of the pixel display unit. Background Art

[0002] Micro-LED is a display technology that miniaturizes and matrices the traditional LED structure and uses CMOS integrated circuit technology to make a driving circuit, thereby realizing the control and driving of each pixel point. Micro-LED has performance advantages such as high brightness, low power consumption, fast response time, high contrast, high resolution, and color saturation, and is regarded as an ideal display technology.

[0003] In related technologies, during the preparation of Micro-LED, a Micro-LED chip is fabricated on a substrate, and then the CMOS driving backplane is physically connected through a bonding metal, and at the same time, electrical connection is achieved through a metal electrode and the bonding metal. However, this manufacturing process requires high-precision alignment, and moreover, it is necessary to bond micro-LED and CMOS separately at the wafer level, which will cause problems in terms of wafer utilization rate and cost, resulting in high process requirements and costs. In addition, the CMOS driving backplane also needs to be adapted to the Micro-LED chip, so the CMOS driving backplane needs to adopt a relatively advanced manufacturing process, further increasing the process cost of Micro-LED. Summary of the Invention

[0004] In view of this, this application provides a pixel display unit, a display panel, and a manufacturing method of the pixel display unit.

[0005] The pixel display unit provided by the embodiments of this application includes:

[0006] A pixel light-emitting array, composed of an array of light-emitting devices and a substrate carrying it;

[0007] A driving chip, composed of a pixel circuit array of a driving circuit and a substrate carrying it;

[0008] An interposer, as a physical carrier of the pixel light-emitting array and the driving chip, is provided with a plurality of conductive channels to realize electrical connection between the pixels of the light-emitting array and the pixel circuit array, and there is a one-to-one correspondence between the pixels of the pixel light-emitting array and the pixel circuit array.

[0009] In some embodiments, the interposer includes;

[0010] A substrate, on which the conductive channels are formed, and the driving chip and the pixel light-emitting array are located on the substrate.

[0011] In some embodiments, the interposer layer includes:

[0012] a substrate;

[0013] an insulating layer located on the substrate, the insulation resistance value of the insulating layer being greater than that of the substrate, the conductive channels being formed in the insulating layer, and the driving chip and the pixel light-emitting array being located on a side of the insulating layer away from the substrate.

[0014] In some embodiments, the insulating layer includes multiple layers, and the conductive channels are distributed in each insulating layer.

[0015] In some embodiments, the substrate includes one of a silicon wafer, quartz, silicon carbide, or a printed circuit board.

[0016] In some embodiments, metal pads are further formed at both ends of the conductive channels in the interposer layer, the driving chip is bonded to the metal pad at one end of the conductive channel, and the pixel light-emitting array is bonded to the metal pad at the other end of the conductive channel.

[0017] In some embodiments, the pixel display unit further includes:

[0018] a packaging layer located on a side of the interposer layer away from the driving chip, and the packaging layer is formed with metal pads electrically connected to the driving chip.

[0019] In some embodiments, the pixel light-emitting array includes Micro-LEDs.

[0020] The display panel according to the embodiment of the present application includes the pixel display unit described above.

[0021] In some embodiments, the pixel display unit includes a plurality of units, and the plurality of pixel display units are arranged in an array along a first direction and a second direction, and the first direction and the second direction are different.

[0022] The manufacturing method of the pixel display unit provided by the embodiment of the present application includes:

[0023] providing an interposer layer, a pixel light-emitting array, and a driving chip, the interposer layer being formed with a plurality of conductive channels, the pixel light-emitting array being composed of an array of light-emitting devices and a substrate carrying the same, and the driving chip being composed of a pixel circuit array of a driving circuit and a substrate carrying the same;

[0024] bonding the driving chip to the interposer layer, and electrically connecting the pixel circuit array to one end of the conductive channel;

[0025] Bond the pixel light-emitting array to the interposer to generate the pixel display unit. The pixel light-emitting array is electrically connected to the other end of the conductive channel so that the pixel light-emitting array is electrically connected to the pixel circuit array through the conductive channel. There is a one-to-one correspondence between the pixels of the pixel light-emitting array and the pixel circuit array.

[0026] In some embodiments, the manufacturing method further includes:

[0027] Provide a substrate;

[0028] Form multiple conductive channels and metal pads on the substrate through a lift-off process to generate the interposer. The metal pads are located at both ends of the conductive channels to be bonded to the driving chip and the pixel light-emitting array respectively.

[0029] In some embodiments, the manufacturing method further includes:

[0030] Provide a substrate;

[0031] Form an insulating layer on the substrate through a deposition process;

[0032] Form multiple conductive channels and metal pads on the insulating layer through a lift-off process to generate the interposer. The metal pads are located at both ends of the conductive channels to be bonded to the driving chip and the pixel light-emitting array respectively.

[0033] In some embodiments, multiple layers of insulating layers are formed, and the conductive channels are distributed in each insulating layer.

[0034] In some embodiments, the manufacturing method further includes:

[0035] Form a packaging layer on the side of the interposer facing away from the driving chip. The packaging layer is formed with metal pads electrically connected to the driving chip.

[0036] In some embodiments, bonding the driving chip to the interposer includes:

[0037] Bond the driving chip to the interposer through a flip-chip bonding process or a wire bonding process.

[0038] In some embodiments, bonding the pixel light-emitting array to the interposer includes:

[0039] Bond the pixel light-emitting array to the interposer through a eutectic bonding process.

[0040] In the pixel display unit, manufacturing method, and display panel according to the embodiments of the present application, the driving chip and the pixel light-emitting array are respectively bonded to the intermediate layer, and then the pixel circuit array of the driving chip and the pixel light-emitting array are respectively electrically connected to the conductive channels formed in the intermediate layer, so that the pixel circuit array of the driving chip and the pixel light-emitting array are electrically connected through the conductive channels. Moreover, a one-to-one correspondence relationship is satisfied between the pixel points of the pixel light-emitting array and the pixel circuit array, so that the driving chip can control and drive the pixel light-emitting array. Since the driving chip and the pixel light-emitting array are respectively bonded to the intermediate layer, the pixel circuit array of the driving chip does not need to be aligned and connected to the pixel light-emitting array one by one, so that the pixel pitch of the pixel circuit array in the driving chip does not need to be adapted to the pixel pitch of the pixel light-emitting array. In this way, the driving chip can be prevented from being affected by the pixel light-emitting array during the manufacturing process, reducing the process difficulty of the driving chip, simplifying the process operation of the pixel display unit, and reducing the process cost of the pixel display unit.

[0041] Additional aspects and advantages of the present application will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description of the embodiments in conjunction with the drawings, where:

[0043] Figure 1 is a schematic structural diagram of the pixel display unit according to some embodiments of the present application from a top view angle;

[0044] Figure 2 is a schematic structural diagram of the pixel display unit according to some embodiments of the present application from a main view angle;

[0045] Figure 3 is another schematic structural diagram of the pixel display unit according to some embodiments of the present application from a main view angle;

[0046] Figure 4 is a schematic structural diagram of the pixel display unit according to some embodiments of the present application from a top view angle;

[0047] Figure 5 is a schematic block diagram of the driving chip according to some embodiments of the present application;

[0048] Figure 6 is a schematic block diagram of the sub-pixel circuit according to some embodiments of the present application;

[0049] Figure 7 is a schematic diagram of the substrate according to some embodiments of the present application;

[0050] Figure 8It is a schematic flowchart of a method for manufacturing a pixel display unit according to some embodiments of the present application;

[0051] Figures 9 - 11 It is a schematic scenario diagram of a method for manufacturing a pixel display unit according to some embodiments of the present application;

[0052] Figures 12 - 13 It is a schematic flowchart of a method for forming an interlayer according to some embodiments of the present application;

[0053] Figures 14 - 17 It is a schematic scenario diagram of forming an interlayer according to some embodiments of the present application;

[0054] Figure 18 It is a schematic flowchart of a method for manufacturing a pixel display unit according to some embodiments of the present application;

[0055] Figure 19 It is a schematic structural diagram of forming a packaging layer on the interlayer according to some embodiments of the present application.

[0056] Main element symbol description:

[0057] 10 - Pixel display unit, 11 - Interlayer, 111 - Conductive channel, 112 - Metal pad, 113 - Substrate, 114 - Insulating layer, 12 - Driving chip, 121 - Digital interface, 122 - Power module, 123 - Clock module, 124 - Timing control logic module, 125 - Row / column scanning module, 126 - Pixel circuit, 1261 - Sub - pixel circuit, Memory in Pixel - Pixel latch unit, PWMGen - Pulse width modulation generation unit, Current Circuit - Current generation unit, 13 - Pixel light - emitting array, 14 - Packaging layer. Detailed implementation manners

[0058] The embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present application and should not be construed as limiting the present application.

[0059] Currently, the display solutions for augmented reality (AR) products on the market mainly include liquid crystal on silicon (L - CoS) display, digital light processing (DLP) display, micro - organic light - emitting diode (Micro OLED), and micro - light - emitting diode (Micro LED) display.

[0060] Among them, Micro-LED is a display technology that miniaturizes and matrices the traditional LED structure and uses CMOS integrated circuit technology to make CMOS drive, so as to realize the control and drive of each pixel. Compared with other display technologies, Micro-LED has performance advantages such as high brightness, low energy consumption, fast response time, high contrast, high resolution and color saturation, and is considered by the industry to be the most ideal AR display light-emitting solution. Due to the pursuit of light weight and portability in AR products, a smaller display screen needs to be used to reduce the overall volume of the optical engine module. At the same time, near-eye display requires a high PPI for the display screen pixels to provide high resolution, which requires the display screen to provide as small a pixel pitch as possible.

[0061] However, the traditional OLED drive circuit is not suitable for driving Micro-LED. At present, due to the need for display effects and drive functions in AR products, an advanced CMOS process below 55nm that matches the Micro-LED chip needs to be adopted, and the process of carrying a high-voltage chip is difficult to achieve.

[0062] Moreover, in related technologies, during the preparation of Micro-LED, Micro-LED chips are fabricated on a substrate, and then the CMOS drive is physically connected through bonding metal, and at the same time, electrical connection is achieved through metal electrodes and bonding metal. In the connection method between the CMOS drive and Micro-LED, a hybrid bonding method needs to be adopted to align and connect each single pixel one by one. Those skilled in the art can understand that Hybrid Bonding is an advanced chip interconnection technology that uses a hybrid bonding method to achieve denser interconnection and smaller form factor. This technology completes bonding through the depression of copper bumps, leaving no gap between die and die or wafer and wafer, and does not require filling with epoxy resin. Although wafer-level hybrid bonding has been successfully developed by the Austrian equipment manufacturer EVG, the equipment is expensive, and the current epitaxial wafers of Micro-LED are still mainly 4-6 inches, and there is no possibility of mass production of 12 inches in the foreseeable future. Therefore, bonding Micro-LED and CMOS drive at the wafer level will cause problems in terms of wafer utilization rate and cost.

[0063] In addition, the bond pads on the drive chip are distributed around, rather than at the positions corresponding to the pixels. Especially when customers use the method of multi-project wafer (MPW) small-batch tape-out for R & D and proofing, the die obtained do not have the possibility of reprocessing.

[0064] In view of this, please combine Figures 1 - 4, an embodiment of the present application provides a display panel, and the display panel includes a pixel display unit 10.

[0065] The pixel display unit 10 includes an interlayer 11, a driving chip 12, and a pixel light-emitting array 13. Among them, the pixel light-emitting array 13 is composed of an array of light-emitting components and a substrate carrying it, and the driving chip 12 is composed of a pixel circuit array of a driving circuit and a substrate carrying it. The interlayer 11 serves as a physical carrier for the pixel light-emitting array 13 and the driving chip 12. The interlayer 11 is provided with a plurality of conductive channels 111, and the conductive channels 111 are used to realize the electrical connection between the pixels of the light-emitting array 13 and the pixel circuit array. There is a one-to-one correspondence between the pixels of the pixel light-emitting array 13 and the pixel circuit array.

[0066] In the display panel and the pixel display unit 10 according to the embodiment of the present application, by using the interlayer 11 as a physical carrier for the pixel light-emitting array 13 and the driving chip 12, the driving chip 12 and the pixel light-emitting array 13 are respectively bonded to the interlayer 11, and the pixel circuit array of the driving chip 12 and the pixel light-emitting array 13 are respectively electrically connected to the conductive channels 111 formed in the interlayer 11. Thus, a one-to-one correspondence between the pixels is satisfied between the pixel light-emitting array and the pixel circuit array. In this way, the pixel display unit 10 can meet the display requirements of AR products. Moreover, since the driving chip 12 and the pixel light-emitting array 13 are respectively bonded to the interlayer 11, a one-to-one correspondence between the pixels can be satisfied between the pixel light-emitting array 11 and the pixel circuit array of the driving chip 12. The pixel circuit array of the driving chip 12 does not need to be aligned and connected to the pixel light-emitting array 13 one by one, so that the pixel pitch of the pixel circuit array in the driving chip 12 does not need to be adapted to the pixel pitch of the pixel light-emitting array 13. The pixel pitch of the pixel circuit array in the driving chip 12 can be designed independently of the pixel light-emitting array 13, which provides flexibility for the design of the driving chip 12. At the same time, the shape and size of the bond pads of the driving chip 12 can be customized according to the manufacturing process of the traditional package of the driving chip 12, and are not limited by the size of the bond pads of the pixel light-emitting array 13, reducing the manufacturing process difficulty of the driving chip 12, simplifying the process operation of the pixel display unit 10, reducing the process cost of the driving chip 12. In addition, since the driving chip 12 and the pixel light-emitting array 13 are respectively bonded to the interlayer 11, the driving chip 12 and the pixel light-emitting array 13 can be designed separately, which is applicable to small-batch sample testing and research and development, greatly reducing the research and development cost of the pixel display unit 10 and facilitating the mass production of the display panel.

[0067] Specifically, the display panel may be a Micro LED display panel, which is applied to electronic devices such as mobile phones, computers, tablets, and wearable devices (such as smart watches, virtual display devices (VR), and augmented display devices (AR)). In this embodiment of the present application, the case where the display panel is applied to an AR device is taken as an example for illustration. In this way, the display panel can endow the AR device with excellent performance such as high brightness, low power consumption, fast response time, high contrast ratio, high resolution, and color saturation. At the same time, the volume of the AR device can be reduced, and the high-resolution requirements of the AR device can be met.

[0068] The pixel display units 10 include a plurality of them, and the plurality of pixel display units 10 are arranged in an array along a first direction and a second direction, and the first direction and the second direction are different. In this embodiment, the first direction and the second direction may be perpendicularly arranged. For example, the first direction may be the horizontal direction of the display panel, and the second direction may be the vertical direction of the display panel, or the first direction may be the vertical direction of the display panel, and the second direction may be the horizontal direction of the display panel. The pixel display units 10 can emit lights of different colors, enabling the display panel to display images.

[0069] Please further combine with Figures 1 - 4 , each pixel display unit 10 includes an intermediate layer 11, a driving chip 12, and a pixel light-emitting array 13. Among them, a plurality of conductive channels 111 are formed in the intermediate layer 11, and the conductive channels 111 can achieve the transmission of electrical signals. The driving chip 12 may be a CMOS chip, which is located on the intermediate layer 11 and is electrically connected to one end of the conductive channels 111 in the intermediate layer 11. The pixel light-emitting array 13 may be a Micro-LED chip, which is located on the intermediate layer 11 and is arranged on the same layer as the driving chip 12. The pixel light-emitting array 13 is electrically connected to the other end of the conductive channels 111 in the intermediate layer 11. The driving chip 12 can provide electrical signals to the pixel light-emitting array 13 through the conductive channels 111, thereby controlling the current and brightness of the pixel light-emitting array 13.

[0070] Please combine with Figure 5 , the driving chip 12 may include a digital interface 121, a power supply module 122, a clock module 123, a timing control logic module 124, a row / column scanning module 125, and a pixel circuit 126. The pixel circuit 126 is respectively connected to the digital interface 121, the power supply module 122, the clock module 123, the row / column scanning module 125, and the timing control logic module 124.

[0071] Please combine with Figure 6, Further, the pixel circuit 126 includes a plurality of sub-pixel circuits 1261, and the plurality of sub-pixel circuits 1261 are arranged in an array to form the above-mentioned pixel circuit array. That is to say, the above-mentioned pixel circuit array is formed by the array of a plurality of sub-pixel circuits 126. Each sub-pixel circuit 1261 can adopt a pixel circuit with a mixed digital and analog modulation method, which can generate the driving current required by the light-emitting devices in the pixel light-emitting array 13 and modulate its light-emitting duration, thereby determining the brightness of the light-emitting devices.

[0072] The sub-pixel circuit 1261 includes a pixel latch unit Memory in Pixel, a pulse-width modulation generation unit PWMGen, and a current generation unit Current Circuit. Among them, the pulse-width modulation generation unit PWM Gen is respectively connected to the pixel latch unit Memory in Pixel and the current generation unit Current Circuit. The current generation unit CurrentCircuit is also connected to the light-emitting devices of the pixel light-emitting array 13. The pixel latch unit MIP adopts the pixel latch design technology (Memory in Pixel). The pixel latch unit Memory in Pixel directly integrates a memory in the pixel. The pixel latch unit Memory in Pixel can reduce the display and standby power consumption of the display panel by reducing the refresh frequency and other means. The pulse-width modulation generation unit PWM Gen is used to provide a PWM signal to the current generation unit Current Circuit. The current generation unit Current Circuit is used to generate a driving current according to the PWM signal and provide it to the light-emitting devices of the pixel light-emitting array 13 to drive the light-emitting devices of the pixel light-emitting array 13 to emit light.

[0073] In some embodiments, the interposer 11 includes a substrate 113, and the conductive channels 111 are formed on the substrate 113. The driving chip 12 and the pixel light-emitting array 13 are located on the substrate 113.

[0074] In this embodiment, the interposer 11 is mainly composed of a substrate 113 and conductive channels 111. Among them, the substrate 113 can be made of an insulating material, so that the substrate 113 has good insulation performance. The substrate 113 can be, but is not limited to, a silicon wafer, quartz, silicon carbide, sapphire, a printed circuit board, or even a conductive material with an insulating layer deposited on its surface, etc.

[0075] In this way, the driving chip 12 and the pixel light-emitting array 13 can be respectively bonded to the interposer 11 and electrically connected through the conductive channels 111, and the manufacturing process of the interposer 11 is simple.

[0076] For example, please refer to Figure 7, in some examples, the interposer 113 can be made of a wafer with a low doping concentration and weak conductivity. That is, the interposer 113 can be obtained by performing a series of processings on the wafer. The wafer can be a semiconductor wafer (Wafer) or a Die. When the interposer 11 is a Die, the driving chip 12 and the pixel light-emitting array 13 are respectively attached to the interposer 11 in a die-to-die form. In this way, small-batch sampling and research and development can be achieved, reducing the research and development cost. When the interposer 11 is a Wafer, it can be a 2- to 12-inch wafer. The driving chip 12 and the pixel light-emitting array 13 can be respectively attached to the wafer in a die-to-wafer form, and then the interposer 11 is diced. In this way, it can be applied to mass production.

[0077] Please refer to Figures 1 - 3 , in certain embodiments, the interposer 11 includes a substrate 113 and an insulating layer 114. The insulating layer 114 is located on the substrate 113. The insulation resistance value of the insulating layer 114 is greater than that of the substrate 113. The conductive channels 111 are formed in the insulating layer 114. The driving chip 12 and the pixel light-emitting array 13 are located on the side of the insulating layer 114 facing away from the substrate 113.

[0078] In this embodiment, the interposer 11 is mainly composed of a substrate 113, an insulating layer 114, and conductive channels 111. Among them, the insulating layer 114 can be made of an insulating material (such as silicon dioxide SiO2). The insulating layer 114 has good insulation performance. The insulating layer 114 can be formed on the surface of the substrate 113 through a deposition process. The conductive channels 111 can be formed on the side of the insulating layer 114 facing away from the substrate 113 through a lift-off lithography process. It can be understood that since the driving chip 12 and the pixel light-emitting array 13 are located on the side of the insulating layer 114 facing away from the substrate 113, and the insulating layer 114 has good insulation effect, the substrate 113 can also use a material with general insulation effect. For example, the substrate 113 can be a silicon wafer doped with other materials resulting in general insulation effect.

[0079] In this way, the driving chip 12 and the pixel light-emitting array 13 can be respectively bonded to the interposer 11 and electrically connected to each other through the conductive channels 111. Moreover, since the insulating layer 114 of the interposer 11 has good insulation, it can prevent external factors such as external moisture, oxygen, and dust from affecting the driving chip 12 and the pixel light-emitting array 13, improving the quality of the pixel display unit 10.

[0080] Furthermore, the insulating layer 114 can be a single layer or a multi-layer structure. Please refer to Figure 2 , when the insulating layer 114 is a single layer, multiple conductive channels 111 can be formed at intervals in the insulating layer 114. Please refer to Figure 3When the insulating layer 114 is a multi-layer structure, the conductive channels 111 can be formed in each insulating layer 114 as required. In this way, mutual interference between the conductive channels 111 can be avoided.

[0081] Please combine Figures 2 - 3 In some embodiments, the interposer 11 further forms metal pads 112. The metal pads 112 are located at both ends of the conductive channel 111, the driver chip 12 is bonded to the metal pad 112 at one end of the conductive channel 111, and the pixel light emitting array 13 is bonded to the metal pad 112 at the other end of the conductive channel 111.

[0082] Specifically, the metal pad 112 can be formed on the surface of the insulating layer 114 or the substrate 113 by a photolithography stripping process. The metal pad 112 may include a metal pad 112 of a driving chip 12 and a metal pad 112 of a pixel light-emitting array 13. The metal pad 112 of the driving chip 12 and the metal pad 112 of the pixel light-emitting array 13 are respectively located at two ends of the conductive channel 111 and exposed to the intermediate layer 11, and are electrically connected to the conductive channel 111, wherein the metal pad 112 of the driving chip 12 is used to achieve bonding with the driving chip 12, and the metal pad 112 of the pixel light-emitting array 13 is used to achieve bonding with the pixel light-emitting array 13.

[0083] The shape and size of the metal pad 112 of the driver chip 12 can be customized according to the process of the driver chip 12, and the shape and size of the metal pad 112 of the pixel light-emitting array 13 can be customized according to the process of the pixel light-emitting array 13. For example, in some examples, the size of the metal pad 112 of the driver chip 12 is larger than the metal pad 112 of the pixel light-emitting array 13, and the metal pad 112 of the driver chip 12 is square, and the metal pad 112 of the pixel light-emitting array 13 is round.

[0084] Furthermore, the driver chip 12 can be bonded to the metal pad 112 by a wire bond process or a flip chip bond process. And the pixel light emitting array 13 can be bonded to the metal pad 112 by a eutectic bond process, so that the driver chip 12 and the pixel light emitting array 13 are respectively bonded to the intermediate layer 11, and the driver chip 12 is electrically connected to the pixel light emitting array 13. In this way, the process operation is simplified and the process cost is reduced.

[0085] Please combine Figure 4 In some embodiments, the pixel display unit 10 further includes a packaging layer 14 , which is located on a side of the intermediate layer 11 away from the driver chip 12 , and the packaging layer 14 is formed with a metal pad 112 electrically connected to the driver chip 12 .

[0086] In this way, the driving chip 12 can be connected to an external circuit through the metal pads 112 of the encapsulation layer 14.

[0087] Please refer to Figures 8 - 11 , an embodiment of the present application provides a manufacturing method of a pixel display unit 10, including the steps of:

[0088] S1, providing an interposer, a pixel light-emitting array, and a driving chip, the interposer is formed with a plurality of conductive channels, the pixel light-emitting array is composed of an array of light-emitting devices and a substrate carrying the same, and the driving chip is composed of a pixel circuit array of a driving circuit and a substrate carrying the same;

[0089] S2, bonding the driving chip to the interposer, and electrically connecting the pixel circuit array to one end of the conductive channel;

[0090] S3, bonding the pixel light-emitting array to the interposer to generate a pixel display unit, the pixel light-emitting array is electrically connected to the other end of the conductive channel so that the pixel light-emitting array is electrically connected to the pixel circuit array through the conductive channel, and there is a one-to-one correspondence between the pixel points between the pixel light-emitting array and the pixel circuit array.

[0091] In the manufacturing method of the embodiment of the present application, by separately bonding the interposer driving chip and the pixel light-emitting array to the interposer, and then electrically connecting the pixel circuit array of the driving chip and the pixel light-emitting array to the conductive channels of the interposer respectively, the pixel circuit array of the driving chip and the pixel light-emitting array are electrically connected through the conductive channels, so that a one-to-one correspondence between the pixel points can be satisfied between the pixel light-emitting array and the pixel circuit array. Thus, the pixel display unit can meet the display requirements of AR products. And, since the driving chip and the pixel light-emitting array are separately bonded to the interposer, a one-to-one correspondence between the pixel points can be achieved between the pixel light-emitting array and the pixel circuit array of the driving chip. The pixel circuit array of the driving chip does not need to be aligned and connected to the pixel light-emitting array one by one, and the pixel pitch of the pixel circuit array in the driving chip does not need to be adapted to the pixel pitch of the pixel light-emitting array, so that the pixel pitch of the pixel circuit array in the driving chip can be designed independently of the pixel light-emitting array, providing flexibility for the design of the driving chip. At the same time, the shape and size of the bond pad of the driving chip can be customized according to the manufacturing process of the traditional encapsulation of the driving chip, and will not be limited by the size of the bond pad of the pixel light-emitting array, reducing the manufacturing process difficulty of the driving chip, simplifying the process operation of the pixel display unit, reducing the process cost of the driving chip. In addition, since the driving chip and the pixel light-emitting array are separately bonded to the interposer, the driving chip and the pixel light-emitting array can be designed separately, which is suitable for both small-batch sample testing and R & D, and large-batch production.

[0092] Please refer toFigure 12 , in some embodiments, the manufacturing method further includes:

[0093] S01, providing a substrate;

[0094] S02, forming a plurality of conductive channels and metal pads on the substrate through a lift-off process to generate an interlayer, and the metal pads are located at both ends of the conductive channels to be bonded to the driving chip and the pixel light-emitting array respectively.

[0095] It can be understood that the lift-off process is a process of obtaining a patterned photoresist structure or a mask such as metal on a substrate by photolithography, depositing a target coating on the mask by a coating process, and then obtaining a target graphic structure consistent with the pattern by dissolving the photoresist with a stripping solution (also known as a lift-off solution) or mechanically removing the metal hard mask.

[0096] In this way, by forming conductive channels and metal pads on the substrate to generate an interlayer, while realizing the bonding with the driving chip and the pixel light-emitting array, the structure of the interlayer is simple, and the manufacturing process difficulty of the interlayer is reduced.

[0097] Please refer to Figures 13 - 17 , in some embodiments, the manufacturing method further includes:

[0098] S03, providing a substrate;

[0099] S04, forming an insulating layer on the substrate through a deposition process;

[0100] S05, forming a plurality of conductive channels and metal pads on the insulating layer through a lift-off process to generate an interlayer, and the metal pads are located at both ends of the conductive channels to be bonded to the driving chip and the pixel light-emitting array respectively.

[0101] In this way, by forming an insulating layer on the substrate and then forming conductive channels and metal pads on the insulating layer to generate an interlayer, while the interlayer realizes the bonding with the driving chip and the pixel light-emitting array, it also has a good insulating effect, avoiding the driving chip and the pixel light-emitting array bonded on the interlayer from being externally interfered, and ensuring the quality of the pixel display unit.

[0102] It should be noted that when forming a plurality of conductive channels on the insulating layer through the lift-off process, the conductive channels can be a single-layer structure or a multi-layer structure. For example, please refer to Figure 16 , when the conductive channels adopt a single-layer structure, a layer of insulating layer is formed on the substrate, and a plurality of conductive channels and metal pads are formed in the insulating layer through the lift-off process. Moreover, the conductive channels can be in the insulating layer, and the metal pads are exposed outside the insulating layer so as to be easily bonded to the driving chip or the pixel light-emitting array. Another example is Figure 17When the conductive channel adopts a multi-layer structure, multiple insulating layers can be formed on the substrate, and then the conductive channels are distributed in each insulating layer as needed through a stripping process, and finally a metal pad is formed on the surface insulating layer. In this way, the conductive channels are separated by the insulating layer to avoid mutual interference between the conductive channels.

[0103] Please combine Figure 18 and 19 In some embodiments, the preparation method further comprises:

[0104] S5, forming a packaging layer on a side of the intermediary layer away from the driver chip, wherein the packaging layer is formed with a metal pad electrically connected to the driver chip.

[0105] In this embodiment, a packaging layer can be formed through a packaging process to complete the connection between the driver chip and the metal pad of the packaging layer. In this way, the driver chip can be connected to the external circuit outside the packaging layer. At the same time, the packaging layer can effectively prevent the intermediary layer from being physically damaged and corroded by external erosion.

[0106] In some embodiments, step S2 comprises:

[0107] S21, bonding the driver chip to the interposer through a flip chip bonding process or a wire bonding process.

[0108] Specifically, the driver chip is welded to the metal pad in the intermediary layer by a flip chip bonding process or a wire bonding process, thereby achieving bonding between the driver and the intermediary layer.

[0109] In this way, the process operation of bonding the driver chip to the interposer is simplified, and the process cost is reduced.

[0110] In some embodiments, step S3 comprises:

[0111] S31, bonding the pixel light emitting array to the interposer through a eutectic bonding process.

[0112] Specifically, the pixel light emitting array and the metal pad are welded together through a eutectic welding process, thereby achieving bonding between the pixel light emitting array and the intermediate layer.

[0113] Understandably, the eutectic bond is a metal connection technology. The principle of the Eutectic Bond process is to heat the solder joint of the metal component to a high enough temperature so that the metal at that point melts and forms a liquid alloy called eutectic. The Eutectic Bond process has the advantages of high welding strength, low welding temperature, and fast welding speed. Therefore, bonding the pixel light-emitting array to the interposer through the Eutectic Bond process can ensure the stable bonding of the pixel light-emitting array and the interposer, improving the connection reliability.

[0114] In several embodiments provided by the present application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection between each other can be through some interfaces. The indirect coupling or communication connection of the devices or units can be in electrical, mechanical, or other forms.

[0115] In addition, in each embodiment of the present application, each functional unit can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit.

[0116] As described above, the above are only specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A pixel display unit, characterized in that, The pixel display unit includes: A pixel light-emitting array, which consists of an array of light-emitting devices and a substrate carrying the same; A driving chip, which consists of an array of pixel circuits of a driving circuit and a substrate carrying the same; An interposer, as a physical carrier of the pixel light-emitting array and the driving chip, is provided with a plurality of conductive channels to achieve electrical connection between the pixels of the light-emitting array and the pixel circuit array, and there is a one-to-one correspondence between the pixels of the pixel light-emitting array and the pixel circuit array.

2. The pixel display unit according to claim 1, characterized in that The interposer includes: A substrate, on which the conductive channels are formed, and the driving chip and the pixel light-emitting array are located on the substrate.

3. The pixel display unit according to claim 1, characterized in that, The interposer includes: A substrate; An insulating layer located on the substrate, the insulation resistance value of the insulating layer is greater than that of the substrate, the conductive channels are formed in the insulating layer, and the driving chip and the pixel light-emitting array are located on the side of the insulating layer away from the substrate.

4. The pixel display unit according to claim 3, wherein The insulating layer includes multiple layers, and the conductive channels are distributed in each insulating layer.

5. The pixel display unit according to claim 2 or 3, characterized in that The substrate includes one of a silicon wafer, quartz, silicon carbide or a printed circuit board.

6. The pixel display unit according to claim 1, wherein The interposer also forms metal pads at both ends of the conductive channels, the driving chip is bonded to the metal pad at one end of the conductive channel, and the pixel light-emitting array is bonded to the metal pad at the other end of the conductive channel.

7. The pixel display unit according to claim 1, wherein The pixel display unit further includes: A packaging layer, which is located on the side of the interposer away from the driving chip, and the packaging layer forms a metal pad electrically connected to the driving chip.

8. The pixel display unit according to claim 1, characterized in that, The pixel light-emitting array includes Micro-LEDs.

9. A display panel, characterized in that, Including the pixel display unit according to any one of claims 1-8.

10. The display panel according to claim 9, characterized in that, There are multiple pixel display units, and the multiple pixel display units are arranged in an array along a first direction and a second direction, and the first direction and the second direction are different.

11. A manufacturing method of a pixel display unit, characterized in that, The manufacturing method includes: Providing an interposer, a pixel light-emitting array and a driving chip, the interposer is formed with a plurality of conductive channels, the pixel light-emitting array consists of an array of light-emitting devices and a substrate carrying the same, and the driving chip consists of an array of pixel circuits of a driving circuit and a substrate carrying the same; Bonding the driving chip to the interposer, and electrically connecting the pixel circuit array to one end of the conductive channel; Bonding the pixel light-emitting array to the interposer to generate the pixel display unit, and electrically connecting the pixel light-emitting array to the other end of the conductive channel so that the pixel light-emitting array is electrically connected to the pixel circuit array through the conductive channel, and there is a one-to-one correspondence between the pixels of the pixel light-emitting array and the pixel circuit array.

12. The manufacturing method according to claim 11, characterized in that, The manufacturing method further includes: Providing a substrate; Forming a plurality of the conductive channels and metal pads on the substrate through a lift-off lithography process to generate the interposer, and the metal pads are located at both ends of the conductive channels to be bonded to the driving chip and the pixel light-emitting array respectively.

13. The manufacturing method according to claim 11, characterized in that, The manufacturing method further includes: Providing a substrate; Forming an insulating layer on the substrate by a deposition process; A plurality of the conductive channels and metal pads are formed on the insulating layer through a lift-off lithography process to generate the interposer, and the metal pads are located at both ends of the conductive channels to be bonded to the driving chip and the pixel light-emitting array respectively.

14. The manufacturing method according to claim 13, wherein The insulating layer is formed in multiple layers, and the conductive channels are distributed in each insulating layer.

15. The manufacturing method according to claim 11, characterized in that, The manufacturing method further includes: Forming a packaging layer on a side of the interposer facing away from the driving chip, and the packaging layer is formed with metal pads electrically connected to the driving chip.

16. The manufacturing method according to claim 11, wherein The bonding of the driving chip to the interposer includes: Bonding the driving chip to the interposer through a flip-chip bonding process or a wire bonding process.

17. The manufacturing method according to claim 11, characterized in that, The bonding of the pixel light-emitting array to the interposer includes: Bonding the pixel light-emitting array to the interposer through an eutectic bonding process.

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