Display device and manufacturing method thereof

Abstract

The application discloses a display device and a manufacturing method thereof. A through hole is arranged on a driving circuit layer of a micro light emitting diode lamp panel, the through hole is used as a fixing position of a support column for mounting a diffusion plate, the support column is directly mounted in the through hole, the support column is fixed, and then the diffusion plate is arranged on the support column. The through hole in the driving circuit layer can be formed by using the same patterning process as each film layer in the driving circuit layer, so that the cost and process difficulty are not increased, and the support column is fixed in the through hole to avoid punching the substrate base plate. Meanwhile, the position of the through hole is fixed, the support column is inserted into the through hole, and relative movement of the support column can be avoided, so that the stability of the support structure can be improved.

Description

Technical Field

[0001] This invention relates to the field of display technology, and in particular to a display device and its manufacturing method. Background Technology

[0002] LCD screens are currently the mainstream display technology, boasting advantages such as low power consumption, small size, and low radiation. However, LCD panels are non-self-emissive and require a backlight module for operation.

[0003] Mini LEDs have become a hot topic in LCD technology as backlights. Unlike traditional LCDs that use side-lit backlights with light guide plates, they use a large number of Mini LEDs as backlights, which not only makes the backlight thinner but also enables more precise dynamic control and improves the dynamic contrast of the LCD.

[0004] In direct-lit backlight modules, diffusers need to be placed at intervals between the light panels to ensure sufficient light mixing between the various light sources. When using Mini LED light panels, if a traditional bracket is used to support the diffusers, holes need to be drilled in the Mini LED light panels, and the bracket passes through the light panels to be fixed to the back plate. However, when Mini LED light panels use glass substrates, the drilling process is more complex and costly. Summary of the Invention

[0005] In some embodiments of the present invention, through-holes are formed on the driving circuit layer of the micro LED lamp board. These through-holes serve as fixed positions for support pillars that mount and support the diffuser plate. The support pillars are directly installed within the through-holes, fixed in place, and then the diffuser plate is placed on the support pillars. The through-holes in the driving circuit layer can be formed using the same patterning process as the various film layers in the driving circuit layer, without increasing cost or process difficulty. Fixing the support pillars within the through-holes avoids drilling holes in the substrate. Simultaneously, the fixed position of the through-holes prevents relative movement of the support pillars, thereby improving the stability of the support structure.

[0006] In some embodiments of the present invention, the driving circuit layer includes a gate metal layer, a gate insulating layer, an active layer, a source / drain metal layer, a planarization layer, a connection electrode, and a reflective layer. The vias are patterned simultaneously with the fabrication of the driving circuit layer, without increasing cost or process complexity. The vias penetrate the gate insulating layer, the planarization layer, and the reflective layer, having the same depth as the driving circuit layer, and exhibit good stability when fixing the support pillars.

[0007] In some embodiments of the present invention, the depth of the through hole is 3μm-4μm.

[0008] In some embodiments of the present invention, each metal layer in the driving circuit layer contains different components and signal lines. In order not to affect the original pattern of each metal layer, vias are set in areas outside the pattern of each metal layer. The orthogonal projection of the vias on the substrate does not overlap with the orthogonal projections of the gate metal layer, active layer and source / drain metal layer on the substrate.

[0009] In some embodiments of the present invention, the support column is fixed to the substrate within the through hole by an adhesive layer, ensuring a more secure connection between the support column and the micro LED board.

[0010] In some embodiments of the present invention, in order to meet the requirements of the thin and light design of the backlight module and to ensure that the micro light-emitting diode has sufficient light mixing distance, the height of the support column in the embodiments of the present invention is less than 6mm.

[0011] In some embodiments of the present invention, signal lines are placed on different metal layers and electrically connected together through vias, which can improve the conductivity of the signal lines, allow for avoidance of components in the circuit, and shorten the length of the signal lines.

[0012] In some embodiments of the present invention, a method for manufacturing a display device includes:

[0013] A pattern of a driving circuit layer is formed on a substrate; the driving circuit layer includes vias penetrating the driving circuit layer and exposed connection electrodes;

[0014] Micro LEDs are welded onto the connecting electrodes;

[0015] Apply adhesive to the through-hole;

[0016] Move the support column into the through hole and fix it in place;

[0017] The diffuser plate is mounted on the support column.

[0018] In some embodiments of the present invention, forming a pattern of a driving circuit layer on a substrate includes:

[0019] A pattern of a gate metal layer is formed on a substrate.

[0020] A pattern of a gate insulating layer is formed on the side of the gate metal layer that faces away from the substrate.

[0021] The active layer and source / drain metal layers are patterned on the side of the gate insulating layer away from the gate metal layer;

[0022] A planarization layer pattern is formed on the side of the active layer and source / drain metal layers away from the gate insulating layer;

[0023] A pattern for connecting electrodes is formed on the side of the planarization layer away from the active layer and the source / drain metal layers;

[0024] A reflective layer pattern is formed on the side of the planarization layer that is away from the active layer and the source / drain metal layer;

[0025] The via penetrates the gate insulating layer, planarization layer, and reflective layer.

[0026] In some embodiments of the present invention, moving the support column into the through hole includes:

[0027] Images of a substrate with a driving circuit layer formed are captured as feature images;

[0028] Determine the location information of the through hole based on the feature image;

[0029] Based on the location information, the supports are moved sequentially into the corresponding through holes.

[0030] In some embodiments of the present invention, through holes are made on the micro light-emitting diode board to fix the support column, which can realize the automatic mounting of the support column. Attached Figure Description

[0031] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic cross-sectional view of the display device provided in an embodiment of the present invention;

[0033] Figure 2 This is a schematic diagram of the cross-sectional structure of the backlight module provided in an embodiment of the present invention;

[0034] Figure 3 A schematic diagram of the cross-sectional structure of the miniature light-emitting diode lamp board provided in an embodiment of the present invention;

[0035] Figure 4 This is a schematic flowchart illustrating a method for manufacturing a display device according to an embodiment of the present invention.

[0036] Among them, 100-backlight module, 200-display panel, 1-micro LED lamp board, 2-support pillar, 3-diffuser plate, 11-substrate, 12-driving circuit layer, 13-micro LED, 121-gate metal layer, 122-gate insulating layer, 123-active layer, 124-source drain metal layer, 125-planarization layer, 126-reflective layer, 127-adhesive layer, e-connection electrode, L-through hole, p-pin, G-gate, S-source, D-drain, a-channel region, s1-first signal line, s2-second signal line, s3-third signal line, s4-fourth signal line. Detailed Implementation

[0037] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. However, the exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to make the present invention more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the figures denote the same or similar structures, and therefore repeated descriptions of them will be omitted. Terms describing position and direction in the present invention are illustrative based on the accompanying drawings, but changes can be made as needed, and all such changes are included within the scope of protection of the present invention. The accompanying drawings of the present invention are for illustrative purposes only and do not represent actual proportions.

[0038] An LCD monitor mainly consists of a backlight module and an LCD panel. The LCD panel itself does not emit light and relies on a backlight module to provide light for brightness display.

[0039] The display principle of a liquid crystal display (LCD) involves placing liquid crystal between two conductive glass plates. The electric field between two electrodes drives the liquid crystal molecules to twist, controlling the transmission or blocking of the backlight, thus displaying the image. Adding a color filter allows for the display of color images.

[0040] Figure 1 A schematic diagram of the cross-sectional structure of the display device provided in an embodiment of the present invention.

[0041] Reference Figure 1 The display device includes a backlight module 100 and a display panel 200. The backlight module 100 is used to provide a backlight source to the display panel 200, and the display panel 200 is used for image display.

[0042] The backlight module 100 is typically located at the bottom of the display device, and its shape and size are adapted to the shape and size of the display device. When used in fields such as televisions or mobile terminals, the backlight module is usually rectangular in shape.

[0043] The backlight module in this embodiment of the invention is a direct-lit backlight module, which is used to emit light uniformly throughout the entire light-emitting surface, providing the display panel with sufficient brightness and uniformly distributed light so that the display panel can display images normally.

[0044] The display panel 200 is located on the light-emitting side of the backlight module 100, and the shape and size of the display panel are usually matched with the backlight module. Typically, the display panel 200 can be set as a rectangle, including a top side, a ground side, a left side, and a right side, wherein the top side and the ground side are opposite each other, the left side and the right side are opposite each other, the top side is connected to one end of the left side and one side of the right side, and the ground side is connected to the other end of the left side and the other end of the right side.

[0045] The display panel 200 is a transmissive display panel, which can modulate the transmittance of light, but does not emit light itself. The display panel 200 has multiple pixel units arranged in an array, and each pixel unit can independently control the transmittance and color of the light incident from the backlight module 100 onto that pixel unit, so that the light transmitted through all pixel units constitutes the displayed image.

[0046] Figure 2 This is a schematic diagram of the cross-sectional structure of the backlight module provided in an embodiment of the present invention.

[0047] Reference Figure 2 The backlight module includes: a miniature light-emitting diode lamp board 1, a support column 2 for supporting the diffuser plate, and a diffuser plate 3 located on the light-emitting side of the miniature light-emitting diode lamp board 1.

[0048] Miniature light-emitting diodes (LEDs) are designed by thinning, miniaturizing, and arraying LEDs. They retain the high efficiency and low power consumption of traditional LEDs while offering a smaller size. Using a miniature LED lamp board 1 as a backlight allows for more precise dynamic control compared to traditional LEDs, thus improving the dynamic contrast of the display device.

[0049] The miniature LED light board 1 in this embodiment of the invention can be driven in a passive or active manner. The active driving mode offers advantages such as low power consumption, crosstalk immunity, and low driving cost. Furthermore, the actively driven miniature LED light board can be fabricated using thin-film technology.

[0050] Reference Figure 2 The miniature light-emitting diode lamp board 1 includes: a substrate 11, a driving circuit layer 12 located on the substrate, and a miniature light-emitting diode 13 electrically connected to the driving circuit layer 12.

[0051] The substrate 11 is located at the bottom of the display device and serves a supporting function. The substrate 11 is rectangular or square in shape and includes a top side, a ground side, a left side, and a right side. The top side and the ground side are opposite each other, and the left side and the right side are opposite each other. The top side is connected to one end of the left side and one side of the right side, respectively, and the ground side is connected to the other end of the left side and the other end of the right side, respectively.

[0052] The size of the substrate 11 is adapted to the size of the display device. Typically, the size of the substrate is slightly smaller than the size of the display device.

[0053] The substrate 11 is made of materials such as glass. Before manufacturing, the glass needs to be cleaned and dried.

[0054] The driving circuit layer 12 is located on the substrate 11, and includes driving elements for driving the micro light-emitting diode to emit light and signal lines. In this embodiment of the invention, the driving circuit layer 12 is fabricated using a thin film transistor (TFT) fabrication process.

[0055] The driving circuit layer 12 consists of multiple metal layers and insulating layers. By patterning the metal layers and insulating layers, a circuit composed of driving elements such as thin-film transistors, capacitors, and resistors with specific interconnections is formed. After the driving circuit layer 12 is electrically connected to the micro LED 13, the driving circuit layer 12 can provide a driving signal to the micro LED 13 to control the micro LED 13 to emit light.

[0056] Reference Figure 2 In this embodiment of the invention, the driving circuit layer 12 includes a through-hole L penetrating all film layers in the driving circuit layer and an exposed connection electrode e. The through-hole L is used to fix the support pillars of the diffuser plate, while the connection electrode e is used to electrically connect to the micro-light-emitting diode 13.

[0057] The connecting electrode e is an exposed pad on the array substrate, and the micro light-emitting diode 13 is typically soldered to the connecting electrode e, thereby achieving an electrical connection between the two.

[0058] The miniature light-emitting diode 13 differs from ordinary light-emitting diodes; it specifically refers to a miniature light-emitting diode chip. Because the miniature light-emitting diode 13 is very small, it allows for better control of the dynamic light emission of the backlight module within smaller zones, thus improving image contrast. In this embodiment of the invention, the size of the miniature light-emitting diode 13 is less than 500 μm.

[0059] The miniature LED light board 1 may include only one color of miniature LED 13 or multiple colors of miniature LED 13, and there is no limitation here.

[0060] A diffuser plate 3 is mounted on the support column 2. The diffuser plate 3 is located on the light-emitting side of the miniature LED lamp panel 1. The shape of the diffuser plate 3 is the same as that of the miniature LED lamp panel 1. Typically, the diffuser plate 3 can be rectangular or square. The thickness of the diffuser plate 3 is 1.5mm-3mm.

[0061] The function of diffuser plate 3 is to scatter the incident light, making the light passing through diffuser plate 3 more uniform. Diffuser plate 3 contains scattering particle material. When light is incident on the scattering particle material, it will continuously undergo refraction and reflection, thereby achieving the effect of scattering the light and realizing the function of uniform light.

[0062] The diffuser plate 3 typically has a higher haze and a more obvious homogenization effect. It can usually be processed by extrusion. The material used for the diffuser plate 3 is generally selected from at least one of polymethyl methacrylate (PMMA), polycarbonate (PC), polystyrene-based materials (PS), and polypropylene (PP).

[0063] In this embodiment of the invention, a certain distance needs to be set between the micro LED lamp board 1 and the diffuser plate 3 to ensure that the light is fully mixed among the micro LEDs 13, thereby ensuring the brightness uniformity of the backlight module.

[0064] Typically, the diffuser plate 3 is fixed to the backplate of the backlight module using a bracket. The bracket for the diffuser plate has clips and limiting pieces, requiring holes to be drilled in the micro-LED lamp board 1, through which the diffuser plate passes before being fixed to the backplate. However, when the micro-LED lamp board uses the array substrate described in the embodiments of this invention, the substrate is usually a glass substrate, making the drilling process complex and costly. If the diffuser plate bracket is directly attached to the surface of the micro-LED lamp board 1, the bracket is prone to slippage, resulting in poor stability.

[0065] In view of this, in this embodiment of the invention, a through hole L is provided on the driving circuit layer 12 of the micro light-emitting diode lamp board 1. The through hole L serves as the fixed position for mounting the support column of the diffuser plate 3. The support column 2 is directly installed in the through hole L to fix the support column 2, and then the diffuser plate 3 is placed on the support column 2.

[0066] The via L in the driving circuit layer 12 can be formed using the same patterning process as each film layer in the driving circuit layer 12, without increasing cost or process difficulty. The support pillar 2 is fixed in the via L, avoiding the need to drill holes in the substrate. At the same time, the fixed position of the via L and the insertion of the support pillar 2 into the via L can prevent relative movement of the support pillar 2, thereby improving the stability of the support structure.

[0067] Figure 3 A schematic diagram of the cross-sectional structure of a miniature light-emitting diode lamp board provided in an embodiment of the present invention.

[0068] Reference Figure 3 In this embodiment of the invention, the driving circuit layer includes: a gate metal layer 121, a gate insulating layer 122, an active layer 123, a source / drain metal layer 124, a planarization layer 125, and a reflective layer 126.

[0069] The gate metal layer 121 is located on the substrate 11. The gate metal layer has a pattern including the gate G and the gate line.

[0070] The gate metal layer 121 can be a single or multiple layers of metal such as gold (Au), silver (Ag), copper (Cu), nickel (Ni), platinum (Pt), aluminum (Al), molybdenum (Mo), or chromium (Cr), or it can also be a metal layer of aluminum (Al):neodymium (Nd) alloy or molybdenum (Mo):tungsten (W) alloy.

[0071] The pattern of the gate metal layer 121 can be formed using a single patterning process.

[0072] The gate insulating layer 122 is located on the surface of the gate metal layer 121 facing away from the substrate 11. The gate insulating layer 122 is used to insulate the gate metal layer 121, thereby allowing other metal layers to be formed on the gate insulating layer 122.

[0073] The gate insulating layer 122 can be an inorganic layer of silicon oxide, silicon nitride, or metal oxide, and can include a single layer or multiple layers.

[0074] In this embodiment of the invention, reference is made to Figure 2 The gate insulating layer 122 has a via for forming the aforementioned through hole L, which can be formed in a single patterning process with other patterns of the gate insulating layer.

[0075] The active layer 123 is located on the surface of the gate insulating layer 122 facing away from the gate metal layer 121. The active layer 123 includes a source region and a drain region formed by doping with N-type or P-type impurity ions. The region between the source region and the drain region is an undoped channel region a.

[0076] The active layer 123 can be made of materials such as amorphous silicon or polycrystalline silicon. Polycrystalline silicon can be formed by crystallizing amorphous silicon.

[0077] The source / drain metal layer 124 is located on the surface of the active layer 123 opposite to the gate insulating layer 122. The source / drain metal layer 124 has a pattern including a source (S), a drain (D), a data line, and a pin (p).

[0078] The source / drain metal layer 124 can be a single or multiple layers of gold (Au), silver (Ag), copper (Cu) or aluminum (Al), or it can also be a metal layer of aluminum (Al): copper (Cu) alloy.

[0079] The patterns of the active layer 123 and the source / drain metal layer 124 can be formed using a single patterning process.

[0080] The gate G, active layer, source S, and drain D constitute a thin-film transistor. This embodiment of the invention uses a bottom-gate thin-film transistor as an example for specific illustration. In practical applications, the thin-film transistor can also be fabricated as a top-gate structure, where the active layer 123 of the top-gate structure is located on the bottom side of the gate metal layer 121.

[0081] The planarization layer 125 is located on the surface of the active layer 123 and the source / drain metal layer 124 opposite to the gate insulating layer 122. The planarization layer 125 is used to insulate the active layer 123 and the source / drain metal layer 124, and at the same time to planarize the film surface, which is beneficial for forming other devices on the planarization layer 125.

[0082] The planarization layer 125 can be made of materials such as resin. The vias used to form through holes L and the vias used to expose the drain electrode D and pin p in the source and drain metal layers are formed by a one-time patterning process.

[0083] The connection electrode e is located on the surface of the planarization layer 125 away from the source / drain metal layer 124. The connection electrode e is electrically connected to the drain electrode D and the pin p through the via of the planarization layer 125.

[0084] The connecting electrode e serves as the pad for soldering the miniature LED and can be made of a transparent conductive material. The connecting electrode e is formed only at the location where the miniature LED needs to be soldered, and the two connecting electrodes e connecting the same miniature LED do not contact each other.

[0085] The pattern connecting electrode e is formed using a single patterning process.

[0086] The reflective layer 126 is located on the surface of the planarization layer 125 opposite to the source / drain metal layer 124, and the reflective layer 126 includes an opening that exposes the connection electrode e.

[0087] The reflective layer 126 is a protective layer located above the driving circuit layer, and also serves to diffusely reflect incident light. In this embodiment of the invention, the reflective layer 126 can be coated on the surface of the driving circuit layer with a reflective material such as white oil, and then the location of the connection electrode e used for welding the micro light-emitting diode can be exposed through processes such as etching.

[0088] The reflective layer 126 has the property of reflecting light. Therefore, when the light emitted from the micro LED lamp board is reflected back to the back panel by the components in the backlight module, it can be reflected back to the light-emitting side by the reflective layer 126, thereby improving the utilization efficiency of the light source.

[0089] In this embodiment of the invention, the reflective layer 126, in addition to having an opening for exposing the connecting electrode e, also has a via for forming a through hole L. The above-mentioned pattern of the reflective layer 126 can be formed by a single patterning process.

[0090] Thus, by patterning the various film layers in the driving circuit layer, a through-hole L can be formed that penetrates the gate insulating layer 122, the planarization layer 125, and the reflective layer 126. This through-hole L is used to fix the support pillar, thereby replacing drilling holes in the substrate and fixing the support pillar by means of clips or screws.

[0091] Reference Figure 3 The gate metal layer 121 also includes a first signal line s1 and a second signal line s2. The first signal line s1 and the second signal line s2 are used to transmit detection signals or power signals and are formed together with other patterns of the gate metal layer using a single patterning process.

[0092] The source / drain metal layer 124 also includes a pin p for electrically connecting the connection electrode e and a third signal line s3. The drain D of the thin-film transistor and the pin p are electrically connected to the two electrodes of the micro-LED. The drain D and the pin p are used to provide a drive signal to the micro-LED to control its light emission. The third signal line s3 can also be used to transmit a power signal and is electrically connected to the second signal line s2 in the gate metal layer 121 through a via in the gate insulating layer 122. The pin p, the third signal line s3, and other patterns of the source / drain metal layers are formed using a single patterning process.

[0093] In addition to the connecting electrode e, the film layer where the connecting electrode e is located also includes a fourth signal line s4. The fourth signal line s4 can be used to transmit detection signals. The fourth signal line s4 is electrically connected to the first signal line s1 in the gate metal layer 121 through a via.

[0094] Placing signal lines on different metal layers and electrically connecting them together vias can improve the conductivity of the signal lines, allow for avoidance of components in the circuit, and shorten the length of the signal lines.

[0095] Depend on Figure 3 As can be seen, each metal layer provided in the embodiments of the present invention contains different components and signal lines. In order not to affect the original pattern of each metal layer, the embodiments of the present invention set the via L in the area outside the pattern of each metal layer. The orthographic projection of the via L on the substrate 11 does not overlap with the orthographic projection of the gate metal layer 121, the active layer 123 and the source / drain metal layer 124 on the substrate 11.

[0096] Therefore, by simply adding the via L pattern to the gate insulating layer 122, planarization layer 125 and reflective layer 126 during patterning, the via L can be formed at the required location using the same patterning process as the gate insulating layer 122, planarization layer 125 and reflective layer 126.

[0097] To increase the stability of the support pillar 2, the vias L can be uniformly distributed in the non-patterned areas of the driving circuit layer. Furthermore, to increase the depth of the vias L, they can penetrate all layers of the driving circuit layer, making the depth of the vias L the same as the depth of the driving circuit layer. In this embodiment of the invention, the depth of the vias L can reach 3μm-4μm.

[0098] Reference Figure 3 After the drive circuit layer is fabricated, the support post 2 can be moved into the through hole L and fixed in the corresponding through hole L. In this embodiment of the invention, an adhesive layer 127 can be provided on the substrate 11 located in the through hole L, and then the support post 2 can be moved into the through hole L, so that the support post 2 is fixed to the substrate 11 in the through hole L by the adhesive layer 127.

[0099] The adhesive layer 127 can be formed by dispensing glue. After the support column 2 is in full contact with the adhesive layer, it can be cured to ensure a stronger connection between the support column 2 and the miniature LED light board 1.

[0100] The height of the support column 2 affects the overall thickness of the backlight module and the light mixing distance of the micro light-emitting diode 13. In order to meet the requirements of the thin and light-emitting module and ensure that the micro light-emitting diode has a sufficient light mixing distance, the height of the support column 2 in this embodiment of the invention is less than 6mm.

[0101] The specific height of the support column 2 can be designed according to the combination of optical films in the backlight module, the haze and thickness of the diffuser plate 3, and other requirements. The ratio of the light mixing distance to the spacing between two adjacent micro-LEDs typically reflects the overall thickness of the backlight module and the number of micro-LEDs used. A smaller ratio indicates a smaller light mixing distance and a thinner overall module; and a larger spacing between adjacent micro-LEDs requires fewer micro-LEDs, reducing costs.

[0102] After the diffuser plate 3 is set on the support column 2, an optical film can also be set on the surface of the diffuser plate.

[0103] The optical film is set as a whole layer and its shape is the same as that of the miniature light-emitting diode lamp board 1. It can usually be set as a rectangle or a square.

[0104] The arrangement of optical films allows backlight modules to be adapted to a wide variety of practical applications.

[0105] When the micro-light-emitting diode 13 in the micro-light-emitting diode lamp board 1 is a blue micro-light-emitting diode, the optical film includes a quantum dot layer or a fluorescent layer.

[0106] The quantum dot layer includes red quantum dot materials and green quantum dot materials. The red quantum dot materials emit red light when excited by blue light, and the green quantum dot materials emit green light when excited by blue light. The excited red light, green light and transmitted blue light are mixed to form white light and emitted.

[0107] The fluorescent layer contains fluorescent materials that emit stimulated red and green light. The emitted red and green light, along with the transmitted blue light, are mixed to form white light that is emitted.

[0108] In addition, optical films may also include prism sheets, which can change the exit angle of light, thereby changing the viewing angle of the display device.

[0109] Optical films can also include reflective polarizers. As a type of brightness enhancement film, reflective polarizers can improve the brightness of the backlight module, improve the efficiency of light utilization, and at the same time give the emitted light a polarized property, eliminating the need for a polarizer under the liquid crystal display panel.

[0110] Figure 4 This is a schematic flowchart illustrating a method for manufacturing a display device according to an embodiment of the present invention.

[0111] Reference Figure 4 The method for manufacturing a display device provided in this embodiment of the invention includes:

[0112] S10. A pattern of a driving circuit layer is formed on a substrate; wherein the driving circuit layer includes a through-hole penetrating the driving circuit layer and exposed connection electrodes;

[0113] S20. Weld miniature light-emitting diodes onto the connecting electrodes;

[0114] S30. Apply adhesive to the through hole;

[0115] S40. Move the support column into the through hole and fix it;

[0116] S50. Place the diffuser plate on the support column.

[0117] By setting through holes on the driving circuit layer of the miniature light-emitting diode lamp board, the through holes are used as fixed positions for the support columns of the diffuser plate. The support columns are directly installed in the through holes, the support columns are fixed, and then the diffuser plate is placed on the support columns.

[0118] The vias in the driving circuit layer can be formed using the same patterning process as the various film layers in the driving circuit layer, without increasing cost or process difficulty. The support pillars are fixed inside the vias, avoiding the need to drill holes in the substrate. At the same time, the fixed position of the vias and the insertion of the support pillars into the vias prevent relative movement of the support pillars, thereby improving the stability of the support structure.

[0119] Specifically, when forming the pattern of the driving circuit layer on the substrate, the pattern of the gate metal layer is first formed on the substrate.

[0120] When forming the pattern of the gate metal layer on the substrate, a metal layer is formed on the substrate; a photoresist layer is formed on the metal layer; a mask is placed above the photoresist layer, and the mask has a pattern in the area other than the gate, gate lines and other signal lines; the photoresist layer is exposed and developed to expose the metal layer other than the pattern required; the exposed metal layer is etched; the remaining photoresist layer is stripped to form the pattern of the gate metal layer.

[0121] The gate metal layer 121 can be a single or multiple layers of metal such as gold (Au), silver (Ag), copper (Cu), nickel (Ni), platinum (Pt), aluminum (Al), molybdenum (Mo), or chromium (Cr), or it can also be a metal layer of aluminum (Al):neodymium (Nd) alloy or molybdenum (Mo):tungsten (W) alloy.

[0122] Then, a pattern of the gate insulating layer is formed on the side of the gate metal layer that is away from the substrate.

[0123] An insulating layer is formed on the gate metal layer; a photoresist layer is formed on the insulating layer; a mask is disposed above the photoresist layer, and the mask has a pattern in the area where the via is located; the photoresist layer is exposed and developed to expose the insulating layer in the area where the via is located; the exposed insulating layer is etched; the remaining photoresist layer is stripped to form the pattern of the gate insulating layer. The pattern of the gate insulating layer includes vias for forming the aforementioned through holes.

[0124] The gate insulating layer can be an inorganic layer of silicon oxide, silicon nitride, or metal oxide, and can include a single layer or multiple layers.

[0125] Then, the active layer and source / drain metal layers are patterned on the side of the gate insulating layer away from the gate metal layer.

[0126] A semiconductor layer is formed on the gate insulating layer, and a metal layer is formed on the semiconductor layer. A photoresist layer is formed on the metal layer. A halftone mask is placed above the photoresist layer. The halftone mask includes a fully transparent area, a partially transparent area, and a light-shielding area. The fully transparent area corresponds to the area where the active layer and source / drain metal layer do not have patterns, the partially transparent area corresponds to the channel area of ​​the active layer, and the light-shielding area corresponds to the area where the active layer and source / drain metal layer have patterns. The photoresist layer is exposed to form a fully exposed area, a partially exposed area, and an unexposed area. After development, the photoresist in the fully exposed area is completely removed. After development, a thinner photoresist layer remains in the partially exposed area, and a thicker photoresist layer remains in the unexposed area. The exposed metal layer and semiconductor layer are etched. The photoresist in the partially exposed area is ashed to remove the photoresist layer in this area, and the metal layer in this area is etched to expose the channel area. The remaining photoresist layer is stripped to form the patterns of the active layer and source / drain metal layer.

[0127] The active layer can be made of materials such as amorphous silicon or polycrystalline silicon, and the source / drain metal layer can be made of single or multiple layers of gold (Au), silver (Ag), copper (Cu) or aluminum (Al), or it can also be made of an aluminum (Al): copper (Cu) alloy metal layer.

[0128] Then, a planarization layer pattern is formed on the side of the active layer and source / drain metal layers that is away from the gate insulating layer.

[0129] An insulating layer of a certain thickness is formed on the active layer and the source / drain metal layers; a photoresist layer is formed on the insulating layer; a mask is placed above the photoresist layer, and the mask has a pattern in the area where the vias are located; the photoresist layer is exposed and developed to expose the insulating layer in the area where the vias are located; the exposed insulating layer is etched; the remaining photoresist layer is stripped to form a planarization layer pattern. The planarization layer pattern includes vias used to form the aforementioned vias.

[0130] The planarization layer can be made of resin and organic insulating materials.

[0131] Then, a pattern for connecting electrodes is formed on the side of the planarization layer opposite to the active layer and the source / drain metal layers.

[0132] A conductive material layer is formed on a planarization layer; a photoresist layer is formed on the conductive material layer; a mask is placed above the photoresist layer, and the mask has a pattern in the area excluding the connecting electrodes and signal lines; the photoresist layer is exposed and developed to expose the conductive material layer in the area excluding the connecting electrodes and signal lines; the exposed conductive material layer is etched; the remaining photoresist layer is stripped to form the pattern of the connecting electrodes and signal lines.

[0133] The connecting electrodes can be made of transparent conductive materials such as indium tin oxide (ITO).

[0134] Then, a reflective layer pattern is formed on the side of the planarization layer that is away from the active layer and the source / drain metal layer.

[0135] A reflective material layer is formed on a planarization layer; a photoresist layer is formed on the reflective material layer; a mask is placed above the photoresist layer, and the mask has a pattern in the area where the via is located; the photoresist layer is exposed and developed to expose the reflective material layer in the area where the via is located; the exposed reflective material layer is etched; the remaining photoresist layer is stripped off to form the pattern of the reflective layer. The pattern of the reflective layer includes vias for forming the aforementioned vias.

[0136] The reflective layer can be made of materials with reflective properties, such as white oil.

[0137] Thus, the driving circuit layer is formed through the above process, and through-hole patterns are added to the pattern of each film layer to form through-holes that penetrate the gate insulating layer, planarization layer and reflective layer.

[0138] After the pattern of the driving circuit layer is formed, the micro LEDs are transferred to the top of the driving circuit layer and aligned with the connection electrodes on the driving circuit layer. Then, the micro LEDs are soldered to the corresponding connection electrodes.

[0139] Then, adhesive is applied inside the through-hole to form the aforementioned adhesive layer, which is used to bond the support pillar to the substrate inside the through-hole.

[0140] In this embodiment of the invention, through holes are made on a miniature light-emitting diode board to fix the support column, which enables automatic mounting of the support column.

[0141] Specifically, a CCD or other camera device is used for positioning and to photograph the miniature LED board. The captured image is used as a feature image, and the position information of the through-hole in the feature image is captured as feature information. Then, the transfer device is controlled to grasp the support column, and the support column is transferred to the corresponding position according to the position information of the through-hole and then released so that the support column is inserted into the corresponding through-hole, making full contact with the adhesive layer inside the through-hole and adhering it to the substrate inside the through-hole.

[0142] After the support pillars are attached, the diffuser plate is placed on the support pillars, and then the optical films are installed. This completes the fabrication of the backlight module in the display device.

[0143] The display panel is then placed on the light-emitting side of the backlight module to complete the manufacturing process of the display device.

[0144] According to the first inventive concept, through-holes are formed on the driving circuit layer of the micro LED lamp board. These through-holes serve as fixed positions for support pillars that mount and support a diffuser plate. The support pillars are directly installed into the through-holes, fixed in place, and then the diffuser plate is placed on the support pillars. The through-holes in the driving circuit layer can be formed using the same patterning process as the various film layers in the driving circuit layer, without increasing cost or process difficulty. Fixing the support pillars in the through-holes avoids drilling holes in the substrate. Furthermore, the fixed position of the through-holes prevents relative movement of the support pillars, thereby improving the stability of the support structure.

[0145] According to the second inventive concept, the driving circuit layer includes a gate metal layer, a gate insulating layer, an active layer, source / drain metal layers, a planarization layer, connecting electrodes, and a reflective layer. The vias are patterned simultaneously with the fabrication of the driving circuit layer, without increasing cost or process complexity. The vias penetrate the gate insulating layer, planarization layer, and reflective layer, having the same depth as the driving circuit layer, and exhibit good stability when fixing the support pillars.

[0146] According to the third inventive concept, each metal layer in the driving circuit layer contains different components and signal lines. In order not to affect the original pattern of each metal layer, vias are set in areas outside the pattern of each metal layer. The orthogonal projection of the vias on the substrate does not overlap with the orthogonal projections of the gate metal layer, active layer and source / drain metal layer on the substrate.

[0147] According to the fourth inventive concept, the support column is fixed to the substrate within the through hole by an adhesive layer, ensuring a more secure connection between the support column and the micro LED board.

[0148] According to the fifth inventive concept, in order to meet the requirements of the thin and light-emitting module and to ensure that the micro light-emitting diode has sufficient light mixing distance, the height of the support column in the embodiment of the present invention is less than 6mm.

[0149] According to the sixth inventive concept, by placing signal lines on different metal layers and electrically connecting them together through vias, the conductivity of the signal lines can be improved, components in the circuit can be avoided, and the length of the signal lines can be shortened.

[0150] According to the seventh invention concept, by making through holes on the miniature light-emitting diode board to fix the support column, the automatic mounting of the support column can be realized.

[0151] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0152] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A display device, characterized in that, include: Display panel, used for image display; A backlight module, located on the light-incident side of the display panel, is used to provide backlight to the display panel; The backlight module includes: Substrate, serving a load-bearing function; A driving circuit layer, located on the substrate, is used to provide driving signals; the driving circuit layer includes a through-hole and exposed connection electrodes; the driving circuit layer includes a gate metal layer, a gate insulating layer, an active layer, a source / drain metal layer, a planarization layer, connection electrodes, and a reflective layer; the gate metal layer includes a first signal line and a second signal line, which are used to transmit detection signals or power signals. The source and drain metal layers include pins for electrically connecting the connection electrodes and a third signal line. The drain and pins of the thin-film transistor are electrically connected to the two electrodes of the micro-light-emitting diode. The drain and pins are used to provide a driving signal to the micro-light-emitting diode to control the micro-light-emitting diode to emit light. The third signal line is used to transmit a power signal and is electrically connected to the second signal line through a via in the gate insulating layer. In addition to the connecting electrode, the film layer where the connecting electrode is located also includes a fourth signal line. The fourth signal line is used to transmit detection signals and is electrically connected to the first signal line through a via. The vias are uniformly distributed in the area outside the metal layer patterns of the driving circuit layer, and the orthographic projection of the vias onto the substrate does not overlap with the orthographic projection of the gate metal layer, active layer and source / drain metal layer in the driving circuit layer onto the substrate. The via penetrates each film layer of the driving circuit layer, and the depth of the via is the same as the depth of the driving circuit layer. The via and each film layer in the driving circuit layer are formed using the same patterning process; the position of the via is fixed. An adhesive layer is provided on the substrate located within the through hole, and then the support post is transferred into the through hole, so that the support post is fixed on the substrate within the through hole by the adhesive layer. A miniature light-emitting diode is electrically connected to the connecting electrode; A diffuser plate is located on top of the support column.

2. The display device as claimed in claim 1, characterized in that, The drive circuit layer includes: A gate metal layer is located on the substrate; the gate metal layer includes a gate and a gate line. A gate insulating layer is located on the surface of the gate metal layer opposite to the substrate. The active layer is located on the surface of the gate insulating layer opposite to the gate metal layer; A source / drain metal layer is located on the surface of the active layer opposite to the gate insulating layer; the source / drain metal layer includes a source, a drain, a data line, and a pin; A planarization layer is located on the surface of the active layer and the source / drain metal layer on the side opposite to the gate insulating layer; A connection electrode is located on the surface of the planarization layer opposite to the source / drain metal layer; the connection electrode is electrically connected to the drain and the pin through a via in the planarization layer. A reflective layer is located on the surface of the planarization layer opposite to the source / drain metal layer, the reflective layer including an opening that exposes the connection electrode.

3. The display device as claimed in claim 2, characterized in that, The depth of the through hole is 3μm-4μm.

4. The display device as claimed in claim 2, characterized in that, The reflective layer is made of white ink.

5. The display device according to any one of claims 1-4, characterized in that, The height of the support column is less than 6mm.

6. A method for manufacturing a display device, characterized in that, include: A pattern of a driving circuit layer is formed on a substrate. The drive circuit layer includes through-holes and exposed connection electrodes. The driving circuit layer includes a gate metal layer, a gate insulating layer, an active layer, a source / drain metal layer, a planarization layer, a connection electrode, and a reflective layer. The gate metal layer includes a first signal line and a second signal line, which are used to transmit detection signals or power signals. The source / drain metal layer includes pins for electrically connecting the connection electrode and a third signal line. The drain and pins of the thin-film transistor are electrically connected to the two electrodes of the micro-LED, and the drain and pins are used to provide driving signals to the micro-LED to control the micro-LED to emit light. The third signal line is used to transmit power signals and is electrically connected to the second signal line through a via in the gate insulating layer. In addition to the connecting electrode, the film layer containing the electrode also includes a fourth signal line, which is used to transmit a detection signal. The fourth signal line is electrically connected to the first signal line through a via. The vias are uniformly distributed in the area outside the metal layer patterns of the driving circuit layer. The orthographic projection of the vias onto the substrate does not overlap with the orthographic projections of the gate metal layer, active layer, and source / drain metal layer in the driving circuit layer onto the substrate. The vias penetrate through each film layer of the driving circuit layer, and the depth of the vias is the same as the depth of the driving circuit layer. The vias and each film layer in the driving circuit layer are formed using the same patterning process. The position of the vias is fixed. A miniature light-emitting diode is welded onto the connecting electrode; Apply adhesive to the through hole; Moving the support post into the through hole and fixing it includes: using a CCD camera to position the micro LED board, taking a picture of the substrate with the driving circuit layer formed on it as a feature image, capturing the position information of the through hole in the feature image, then controlling a transfer device to grab the support post, transferring the support post to the corresponding position according to the position information of the through hole and releasing it, so that the support post is inserted into the corresponding through hole and makes full contact with the adhesive layer on the substrate located in the through hole, and is adhered to the substrate in the through hole; The diffuser plate is placed on the support column.

7. The manufacturing method as described in claim 6, characterized in that, The pattern of forming the driving circuit layer on the substrate includes: A pattern of a gate metal layer is formed on a substrate. A pattern of a gate insulating layer is formed on the side of the gate metal layer that faces away from the substrate. The active layer and source / drain metal layers are patterned on the side of the gate insulating layer opposite to the gate metal layer; A planarization layer pattern is formed on the side of the active layer and the source / drain metal layer opposite to the gate insulating layer; A pattern for connecting electrodes is formed on the side of the planarization layer opposite to the active layer and the source / drain metal layer; A pattern of a reflective layer is formed on the side of the planar layer opposite to the active layer and the source / drain metal layer.

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