Touch display panel and manufacturing method therefor, and touch display apparatus

Abstract

The present disclosure relates to the technical field of display, and relates to a touch display panel and a manufacturing method therefor, and a touch display apparatus. The touch display panel comprises a display area and a fan-out area, wherein the fan-out area is located on one side of the display area. The touch display panel comprises: a base substrate; a planarization layer, formed on one side of the base substrate; a first transparent electrode, formed on the side of the planarization layer away from the base substrate, wherein the first transparent electrode comprises a first portion located in the display area and a second portion located in the fan-out area; and a touch metal wire, formed on the side of the first transparent electrode away from the base substrate and located in the fan-out area, wherein the orthographic projection of the touch metal wire on the base substrate is located within the orthographic projection of the second portion of the first transparent electrode on the base substrate. It is not needed to additionally provide an IC in the touch display panel, so that the production cost of the touch display panel can be effectively controlled; in addition, the display effect and the yield rate can be improved.

Description

Touch display panel and manufacturing method thereof, and touch display device Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a touch display panel and a manufacturing method thereof, and a touch display device. Background Art

[0002] Compared to traditional products, TDDI (Touch and Display Driver Integration) products integrate both the display and touch control within the display, resulting in touch sensitivity, a thin and lightweight design, high display brightness, and low product cost. They are widely used in mobile phones, tablets, and automotive central control displays. However, because an additional layer of touch traces must be added to the fan-out area during screen manufacturing, certain requirements are placed on the trace's load capacity and routing space.

[0003] Traditional TDDI products require high load capacity for fan-out wiring, making them prone to defects. Consequently, fan-out wiring layouts require an increased number of ICs and bezel size to ensure sufficient load capacity. This increases the size of the display panel, hindering miniaturization. Alternatively, fan-out wiring layouts require complex fabrication processes, increasing product costs and reducing production capacity by more than half.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute relevant technology known to ordinary technicians in the field.

[0005] Summary of the Invention

[0006] The purpose of the present disclosure is to overcome the deficiencies of the above-mentioned related technologies and to provide a touch display panel and a manufacturing method thereof, and a touch display device.

[0007] According to one aspect of the present disclosure, a touch display panel is provided, comprising: a display area and a fan-out area, wherein the fan-out area is located on one side of the display area; the touch display panel comprises:

[0008] substrate;

[0009] a flat layer formed on one side of the base substrate;

[0010] A first transparent electrode is formed on a side of the planar layer facing away from the base substrate; the first transparent electrode includes a first portion located in the display area and a second portion located in the fan-out area;

[0011] A touch metal trace is formed on a side of the first transparent electrode facing away from the base substrate and located in the fan-out area. The orthographic projection of the touch metal trace on the base substrate is located within the orthographic projection of the second portion of the first transparent electrode on the base substrate.

[0012] Optionally, half of the difference between the line width of the second portion and the line width of the touch metal trace is greater than half of the distance between the center of the line width of the second portion and the center of the line width of the touch metal trace.

[0013] Optionally, the thickness of the touch metal wiring is greater than the thickness of the first transparent electrode.

[0014] Optionally, the touch metal trace includes a first metal layer, a second metal layer, and a third metal layer stacked in sequence along the base substrate and pointing toward the first transparent electrode.

[0015] Optionally, the first metal layer includes molybdenum; the second metal layer includes aluminum; and the third metal layer includes molybdenum.

[0016] Optionally, the touch display panel further includes:

[0017] a light shielding structure formed on one side of the base substrate and located in the display area;

[0018] a buffer layer formed on a side of the light-shielding structure facing away from the base substrate;

[0019] an active structure formed on a side of the buffer layer facing away from the base substrate and located in the display area;

[0020] a gate insulating layer, formed on a side of the active structure facing away from the substrate;

[0021] a gate electrode formed on a side of the gate insulating layer facing away from the base substrate, and the gate electrode is located in the display area;

[0022] a first metal structure formed on a side of the gate insulating layer facing away from the base substrate, and the first metal structure is prepared in the same layer as the gate and is located in the fan-out region;

[0023] an interlayer dielectric layer, formed on a side of the gate and the first metal structure facing away from the substrate;

[0024] Source and drain electrodes are formed on a side of the interlayer dielectric layer away from the base substrate and located in the display area, and the source and drain electrodes are connected to the gate through vias;

[0025] The second metal structure is formed on a side of the interlayer dielectric layer away from the base substrate, and the second metal structure is prepared in the same layer as the source and drain and is located in the fan-out area.

[0026] Optionally, the touch display panel provided by the present disclosure further includes: a storage capacitor dielectric layer formed on a side of the touch metal trace facing away from the base substrate.

[0027] Optionally, the touch display panel provided by the present disclosure further includes: a second transparent electrode formed on a side of the storage capacitor dielectric layer away from the base substrate, and the second transparent electrode is connected to the drain electrode of the source and drain electrodes through a via hole.

[0028] According to another aspect of the present disclosure, the present disclosure provides a touch display device, including a touch display panel provided by any of the above technical solutions.

[0029] According to another aspect of the present disclosure, a method for manufacturing a touch display panel is provided. The touch display panel includes a display area and a fan-out area, wherein the fan-out area is located on one side of the display area. The method includes:

[0030] providing a substrate;

[0031] forming a planar layer on the base substrate;

[0032] Depositing a first transparent electrode preparation material layer on the flat layer;

[0033] forming a touch metal trace on the preparation material layer of the first transparent electrode, wherein the touch metal trace is located in the fan-out area;

[0034] forming a photoresist layer on the touch metal trace, and controlling the patterned photoresist pattern to cover the top surface and side surfaces of the touch metal trace through a composition process;

[0035] The first transparent electrode is formed into a first transparent electrode by combining the patterned photoresist pattern with the preparation material layer of the first transparent electrode through a composition process; the first transparent electrode includes a first portion located in the display area and a second portion located in the fan-out area;

[0036] The photoresist pattern is stripped.

[0037] Optionally, the method of controlling the patterned photoresist pattern to cover the top surface and side surfaces of the touch metal trace through a composition process includes:

[0038] Providing a mask, and aligning a first pattern of the mask with the touch metal trace;

[0039] The photoresist pattern is obtained in the fan-out area through exposure and development processes, so that the photoresist pattern covers the top surface and side surfaces of the touch metal trace.

[0040] Optionally, an orthographic projection of the first pattern of the mask on the base substrate covers an orthographic projection of the touch metal trace on the base substrate.

[0041] Optionally, half of the difference between the line width of the second portion and the line width of the touch metal trace is greater than half of the distance between the center of the line width of the second portion and the center of the line width of the touch metal trace.

[0042] Optionally, the thickness of the touch metal wiring is greater than the thickness of the first transparent electrode.

[0043] Optionally, the touch metal trace includes a first metal layer, a second metal layer, and a third metal layer stacked in sequence along the base substrate and pointing toward the first transparent electrode.

[0044] Optionally, the first metal layer includes molybdenum; the second metal layer includes aluminum; and the third metal layer includes molybdenum.

[0045] Optionally, before forming the planar layer on the base substrate, the preparation method further comprises:

[0046] forming a light shielding structure on a portion of the base substrate located in the display area;

[0047] forming a buffer layer on the light-shielding structure, wherein the buffer layer is located in the display area and the fan-out area;

[0048] forming an active structure on a portion of the buffer layer located in the display area;

[0049] forming a gate insulating layer on the active structure, wherein the gate insulating layer is located in the display area and the fan-out area;

[0050] forming a gate and a first metal structure on the gate insulating layer, wherein the gate is located in the display area and the first metal structure is located in the fan-out area;

[0051] forming an interlayer dielectric layer on the gate and the first metal structure;

[0052] A source / drain and a second metal structure are formed on the interlayer dielectric. The source / drain are located in the display area and connected to the gate through vias. The second metal structure is located in the fan-out area.

[0053] Optionally, the preparation method further includes: forming a storage capacitor dielectric layer on the touch metal trace.

[0054] Optionally, the preparation method further includes: forming a second transparent electrode on the storage capacitor dielectric layer, wherein the second transparent electrode is connected to the drain electrode of the source and drain electrodes through a via hole.

[0055] In the touch display panel provided by the present disclosure, the touch metal traces are used to transmit touch signals; the first transparent electrode is located between the touch metal traces and the base substrate, and the first transparent electrode is provided with a second portion in the fan-out region to protect the touch metal traces during the manufacturing process. This allows the touch display panel provided by the present disclosure to be manufactured using fewer masks (photomasks or masks), thereby reducing the number of product ICs, ensuring the size of the display device, and saving the overall cost of the finished product.

[0056] When preparing the first transparent electrode provided by the present disclosure, a material layer for the first transparent electrode must first be formed on a flat layer. At this point, the flat layer can be entirely covered by the material layer of the first transparent electrode. Subsequently, a material layer for touch metal traces can be formed entirely on the material layer of the first transparent electrode. This touch metal trace material layer is then patterned to form the touch metal traces. After the touch metal traces are formed, the material layer of the first transparent electrode is patterned to form the first transparent electrode.

[0057] It should be noted that the structural design of the touch display panel provided by the present disclosure enables the flat layer to be patterned without exposing the touch metal traces; subsequently, the patterning process for the first transparent electrode is performed. Specifically, during the formation of the touch metal traces, the flat layer is completely covered by the material layer of the first transparent electrode. The flat layer is not affected by the patterning process during the preparation of the touch metal traces. This prevents the flat layer structure from being damaged during the formation of the first transparent electrode, which could lead to the emission of escaping gases. This further prevents these escaping gases from reacting with the metal within the touch metal traces, forming small black spots, and causing defects, thereby improving the display quality and yield of the touch display panel.

[0058] At the same time, the touch display panel provided by the present disclosure utilizes a fan-out area design pattern so that the photoresist pattern used to prepare the first transparent electrode protects the touch metal trace. Specifically, the touch display panel of the present disclosure sets the orthographic projection of the touch metal trace on the base substrate to be located within the orthographic projection of the second part of the first transparent electrode on the base substrate, so that during the process of patterning the material layer of the first transparent electrode and forming the first transparent electrode, the mask used to prepare the first transparent electrode can form a photoresist pattern with a size larger than the touch metal trace. The photoresist pattern can cover the top and side surfaces of the touch metal trace to prevent the metal in the touch metal trace from reacting with the etching solution used to prepare the first transparent electrode to cause undercutting, thereby further improving the display effect and yield of the touch display panel.

[0059] Therefore, the touch display panel provided by the present disclosure does not need to include an additional IC, and the production cost of the touch display panel can be effectively controlled. At the same time, the display effect and yield can be improved.

[0060] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification, are used to explain the principles of the present disclosure. Obviously, the drawings described below are only some embodiments of the present disclosure, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0062] FIG1 is a schematic plan view of a touch display panel provided by an embodiment of the present disclosure;

[0063] FIG2 is a display area of ​​a touch display panel in the related art;

[0064] FIG3 is a fan-out area of ​​a touch display panel in the related art;

[0065] FIG4 is a display area of ​​another touch display panel in the related art;

[0066] FIG5 is a fan-out area of ​​another touch display panel in the related art;

[0067] FIG6 is a cross-sectional schematic diagram of a fan-out area within a touch display panel according to an embodiment of the present disclosure;

[0068] FIG7 is a plan view of a fan-out area within a touch display panel according to an embodiment of the present disclosure;

[0069] 8 to 9 are schematic diagrams showing changes in film layers during the preparation of a touch display panel provided by an embodiment of the present disclosure;

[0070] FIG10 is a schematic structural diagram of a touch display panel with an undercut formed therein;

[0071] FIG11 is a schematic cross-sectional view of a display area within a touch display panel provided by an embodiment of the present disclosure;

[0072] FIG12 is another cross-sectional schematic diagram of a fan-out area in a touch display panel provided by an embodiment of the present disclosure;

[0073] FIG13 is a metal wiring design within a touch display panel provided by an embodiment of the present disclosure;

[0074] FIG14 shows a schematic plan view of the structure corresponding to FIG13;

[0075] FIG15 shows the structure of the binding area of ​​the touch display panel provided by an embodiment of the present disclosure;

[0076] FIG16 is a schematic flow chart of a method for manufacturing a touch display panel according to an embodiment of the present disclosure;

[0077] FIG17 is a schematic diagram of a process for preparing a touch display panel in the related art;

[0078] 18A to 18C are schematic diagrams showing changes in the film layer using the preparation process in FIG. 17 ;

[0079] FIG19 is a schematic diagram of a process for preparing a touch display panel according to a preparation method provided in an embodiment of the present disclosure;

[0080] FIG20 is a schematic diagram of a process for preparing a touch display panel in another related art;

[0081] 21A to 21C are schematic diagrams showing changes in the film layer within the display area when the touch metal traces are prepared using the flowchart in FIG. 20 ;

[0082] 22A to 22C are schematic diagrams showing changes in the film layer within the fan-out region when fabricating touch metal traces using the flowchart in FIG. 20 ;

[0083] 23A to 23C are schematic diagrams showing changes in the film layer within the binding area when the touch metal traces are prepared using the flowchart in FIG. 20 .

[0084] Reference numerals:

[0085] Related technologies: 1', substrate; 2', light-shielding structure; 3', buffer layer; 4', active structure; 5', gate insulation layer; 6', gate; 7', interlayer dielectric layer; 8', source and drain; 9', planarization layer; 10', first transparent electrode; 11', passivation layer; 12', second transparent electrode; 13', first metal structure; 14', second metal structure; 15', inorganic insulating film layer; 16', touch metal trace; 17', TVC layer;

[0086] The present disclosure includes: 100, display area; 200, fan-out area; 300, binding area; 1, substrate; 2, shading structure; 3, buffer layer; 4, active structure; 5, gate insulating layer; 6, gate electrode; 7, interlayer dielectric layer; 8, source and drain electrode; 9, flat layer; 10, first transparent electrode; 11, touch metal trace; 12, photoresist pattern; 13, passivation layer; 14, second transparent electrode; 15, first metal structure; 16, second metal structure; 17, third metal structure; 18, fourth metal structure. DETAILED DESCRIPTION

[0087] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example 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 so that this disclosure will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art. Like reference numerals in the figures represent identical or similar structures, and thus their detailed descriptions will be omitted. Furthermore, the figures are merely schematic illustrations of the present disclosure and are not necessarily drawn to scale.

[0088] Although relative terms such as "upper" and "lower" are used in this specification to describe the relationship of one illustrated component to another, these terms are used herein for convenience only, such as in accordance with the orientation of the illustrations in the accompanying drawings. It will be understood that if the illustrated device were flipped upside down, the component described as "upper" would become the component "lower." When a structure is referred to as "on" another structure, this may mean that the structure is integrally formed with the other structure, that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure via the other structure.

[0089] The terms "a", "an", "the", "said" and "at least one" are used to indicate the presence of one or more elements / components / etc.; the terms "including" and "having" are used to express open-ended inclusion and mean that additional elements / components / etc. may be present in addition to the listed elements / components / etc.; the terms "first", "second" and "third" etc. are used only as labels and are not intended to limit the quantity thereof.

[0090] According to one aspect of the present disclosure, embodiments of the present disclosure provide a touch display panel. This touch display panel can be referred to as a TDDI (Touch and Display Driver Integration) product. In TDDI products, both the display and touch are integrated within the display screen, resulting in features such as sensitive touch, a thin and lightweight design, high display brightness, and low product cost. These products are widely used in mobile phones, tablet computers, in-vehicle central control displays, and other fields.

[0091] FIG1 is a planar schematic diagram of a touch display panel provided by an embodiment of the present disclosure. As shown in FIG1 , the touch display panel provided by an embodiment of the present disclosure includes a display area 100 and a fan-out area 200, wherein the fan-out area 200 is located on one side of the display area 100, and the fan-out area 200 can be arranged with wiring for transmitting touch signals and wiring for transmitting data. In addition, the touch display panel provided by an embodiment of the present disclosure also includes a binding area 300, which is also located on one side of the display area 100, and the binding area 300 is used to bind the IC (driver chip). It is worth noting that the fan-out area 200 is located between the display area 100 and the binding area 300.

[0092] It is understandable that compared with ordinary display panels, touch display panels require an additional layer of wiring for transmitting touch signals in the fan-out area during the screen manufacturing process. Therefore, certain requirements are placed on the load capacity of the wiring used to transmit touch signals and the layout space of the wiring.

[0093] Figure 2 shows the display area of ​​a touch display panel in the related art. As shown in Figure 2, a light-shielding structure 2', a buffer layer 3', an active structure 4', a gate insulating layer 5', a gate electrode 6', an interlayer dielectric layer 7', a source and drain electrode 8', a planarization layer 9', a first transparent electrode 10', a passivation layer 11', and a second transparent electrode 12' are sequentially formed on a base substrate 1'. Specifically, the orthographic projection of the light-shielding structure 2' on the base substrate 1' lies within the orthographic projection of the active structure 4' on the base substrate 1', and the orthographic projection of the gate electrode 6' on the base substrate 1' lies within the orthographic projection of the light-shielding structure 2' on the base substrate 1'.

[0094] FIG3 shows a fan-out region of a touch display panel in related art, wherein a first metal structure 13 ′ formed on the same layer as the gate 6 ′, an interlayer dielectric layer 7 ′, a second metal structure 14 ′ formed on the same layer as the source and drain 8 ′, a planarization layer 9 ′, and a passivation layer 11 ′ are formed in the fan-out region.

[0095] The first metal structure 13' and the second metal structure 14' are two layers of traces within a touch display panel in the related art. When additional traces are needed to transmit touch signals, these traces must extend the touch display panel outward by a certain amount, occupying a certain amount of horizontal space. This, compared to traditional products, requires a certain increase in the number of ICs and the size of the frame.

[0096] FIG4 is a display area of ​​another touch display panel in the related art; FIG5 is a fan-out area of ​​another touch display panel in the related art. Referring to the structure of the display area shown in FIG4 , compared to the structure shown in FIG2 , after preparing the flat layer 9', an inorganic insulating film layer 15' needs to be prepared, and vias are formed through a mask; thereafter, a preparation material layer for the touch metal trace 16' is formed on the inorganic insulating film layer 15', and the touch metal trace 16' is formed through a mask. A preparation material layer for the TVC layer 17' is formed on the touch metal trace 15', and vias are formed through a mask, and then the original preparation process of the first transparent electrode 10', the passivation layer 11', and the first transparent electrode 12' of the pixel electrode is continued. As shown in FIG5 , an inorganic insulating film layer 15', a touch metal trace 16', and a TVC layer 17' are added to the fan-out area.

[0097] Compared to the touch display panels shown in Figures 2 and 3, the touch display panel manufacturing process shown in Figures 4 and 5 is more complicated. This method will greatly increase product costs and reduce production capacity by more than 100%.

[0098] In view of the above reasons, the present disclosure proposes a touch display panel that can be prepared with fewer masks to achieve the effect of reducing ICs and lowering borders. At the same time, the production cost is effectively controlled, so that the display effect and yield of the touch display panel can be improved.

[0099] Figure 6 is a cross-sectional schematic diagram of a fan-out region 200 within a touch display panel provided by an embodiment of the present disclosure; Figure 7 is a planar schematic diagram of a fan-out region 200 within a touch display panel provided by an embodiment of the present disclosure. As shown in Figures 6 and 7, the present disclosure provides a touch display panel, which includes: a base substrate 1, a planar layer 9 (PLN), a first transparent electrode 10 (CITO), and a touch metal trace 11 (TPM) arranged in sequence. The planar layer 9 is located on one side of the base substrate 1 and is located in the display area 100 and the fan-out region 200 to improve the flatness of the base substrate 1 surface and facilitate the preparation of subsequent structural layers; the first transparent electrode 10 includes a first portion located in the display area 100 and a second portion located in the fan-out region 200; the touch metal trace 11 is located in the fan-out region 200, and the orthographic projection of the touch metal trace 11 on the base substrate 1 is located within the orthographic projection of the second portion of the first transparent electrode 10 on the base substrate 1.

[0100] It should be understood that FIG3 only shows the touch metal traces 11 and the first transparent electrodes 10 . Of course, there are other structural layers in the touch display panel, which are not shown in FIG3 .

[0101] It is worth noting that in the touch display panel provided by the embodiment of the present disclosure, the touch metal trace 11 is used to transmit the touch signal; the first transparent electrode 10 is located between the touch metal trace 11 and the base substrate 1, and the first transparent electrode 10 has a second portion added in the fan-out area 200 to protect the touch metal trace 11 during the manufacturing process. As a result, the touch display panel provided by the embodiment of the present disclosure can be manufactured using fewer masks, which can reduce the number of product ICs, ensure the size of the display device, and at the same time, save the overall cost of the finished product.

[0102] For example, when preparing the first transparent electrode 10 in the embodiment of the present disclosure, as shown in FIG8 , it is necessary to first form a material layer for the first transparent electrode 10 on the flat layer 9. In this case, the flat layer 9 can be entirely covered by the material layer of the first transparent electrode 10. Subsequently, a material layer for the touch metal trace 11 can be formed entirely on the material layer of the first transparent electrode 10, and the material layer for the touch metal trace 11 is patterned to form the touch metal trace 11. After the touch metal trace 11 is formed, the material layer of the first transparent electrode 10 is patterned to form the first transparent electrode 10 as shown in FIG6 .

[0103] It should be noted that the structural design of the touch display panel provided in the embodiments of the present disclosure enables the flat layer 9 to complete the patterning process of the touch metal traces 11 without exposing the flat layer 9; thereafter, the patterning process of the first transparent electrode 10 is performed. Specifically, during the formation of the touch metal traces 11, the flat layer 9 is entirely covered by the material layer of the first transparent electrode 10. The flat layer 9 is not affected by the patterning process during the preparation of the touch metal traces 11. This prevents the structure of the flat layer 9 from being damaged during the formation of the first transparent electrode 10, thereby preventing the emission of escaping gases. This further prevents the escaping gases from reacting with the metal layer within the touch metal traces 11, forming small black spots, and causing defects, thereby improving the display quality and yield of the touch display panel.

[0104] At the same time, the touch display panel provided by the embodiment of the present disclosure utilizes a fan-out region 200 design pattern, so that the photoresist pattern 12 used to prepare the first transparent electrode 10 protects the touch metal trace 11. Specifically, by arranging the orthographic projection of the touch metal trace 11 on the base substrate 1 within the orthographic projection of the second portion of the first transparent electrode 10 on the base substrate 1, the touch display panel of the embodiment of the present disclosure allows the mask used to prepare the first transparent electrode 10 to form a photoresist pattern 12 larger than the touch metal trace 11 during patterning the material layer of the first transparent electrode 10 and forming the first transparent electrode 10. As shown in FIG9 , the photoresist pattern 12 can cover the top and side surfaces of the touch metal trace 11 to prevent the metal in the touch metal trace 11 from reacting with the etching solution used to prepare the first transparent electrode 10, resulting in the undercut phenomenon (marked by the dotted box) as shown in FIG10 , further improving the display effect and yield of the touch display panel.

[0105] Therefore, the touch display panel provided by the embodiment of the present disclosure does not need to include an additional IC, and the production cost of the touch display panel can be effectively controlled. At the same time, the display effect and yield can be improved.

[0106] Considering the alignment issues between film layers during the fabrication of a touch display panel, to prevent the photoresist pattern 12 from failing to fully cover the touch metal trace 11, in one embodiment of the present disclosure, half of the difference between the line width of the second portion and the line width of the touch metal trace 11 is greater than half the distance between the center of the line width of the second portion and the center of the line width of the touch metal trace 11. It should be noted that this structural arrangement ensures that the touch metal trace 11 is effectively covered by the photoresist pattern 12 even when the film layers shift during fabrication.

[0107] In addition, the mask CD of the second portion within the first transparent electrode 10 can also be defined. It is understood that the mask CD is the line width design value of the second portion. In one embodiment of the present disclosure, the line width design value of the second portion is greater than a minimum value, which is the minimum value = the critical dimension of the touch metal trace 11 + the alignment deviation margin between two adjacent layers caused by the equipment used + the BIAS of the first transparent electrode 10 + the overexposure of the first transparent electrode 10;

[0108] The BIAS of the first transparent electrode 10 = |the critical dimension of the first transparent electrode 10 - the critical dimension of the photoresist pattern 12 covering the touch metal trace 11 |.

[0109] It is understood that the critical dimension of the touch metal trace 11 and the critical dimension of the first transparent electrode 10 are referred to as the FICD. In other words, the FICD can also be understood as the line width. During the fabrication of a touch display panel, the critical dimension of the photoresist pattern 12 covering the touch metal trace 11 is referred to as the DICD. In other words, the DICD of the photoresist pattern 12 can also be understood as the DICD of the second portion within the first transparent electrode 10.

[0110] In addition, it is worth noting that in 1:1 exposure, the critical dimension of the second part (DI CD) = the line width design value of the second part (MASK CD); in non-1:1 exposure, there is also a difference in overexposure between the two.

[0111] During the fabrication of a touch display panel, a photoresist layer is applied to the surface of a metal or non-metal layer. After exposure, only the desired photoresist pattern remains. The size of this photoresist pattern is referred to as DI CD. After etching and stripping, the resulting metal or non-metal pattern is referred to as FI CD. In the disclosed embodiment, the critical dimension of the first transparent electrode 10 is the dimension x1 of the first transparent electrode 10 shown in Figure 6 , and the critical dimension of the photoresist pattern 12 covering the touch metal trace 11 is the dimension x2 of the photoresist pattern 12 shown in Figure 9 . Therefore, the BIAS of the first transparent electrode 10 is |x1-x2|.

[0112] It is worth noting that in the above formula, the photoresist pattern 12 is the photoresist pattern 12 used to prepare the second portion of the first transparent electrode 10 ; the overexposure amount of the first transparent electrode 10 is set by the operator during the process of preparing the touch display panel.

[0113] It should be noted that, by setting the above formula, the embodiment of the present disclosure enables the photoresist pattern 12 to effectively cover the top and side surfaces of the touch metal trace 11, thereby effectively protecting the touch metal trace 11 and improving the product quality of the touch display panel obtained by the equipment.

[0114] For example, let's assume the critical dimension of the touch metal trace 11 is 3.0μm, the BIAS of the first transparent electrode 10 is 0.5μm, the alignment margin between two adjacent layers caused by the equipment is 1.89, and 1:1 exposure is used. In this case, the overexposure of the first transparent electrode 10 is equal to 0. From the above values, we can calculate: 3.0 + 1.89 + 0.5 ≈ 5.4μm, that is, the minimum value is approximately equal to 5.4μm.

[0115] It is worth noting that when the MASK CD of the second portion in the first transparent electrode 10 is 5.4 μm, that is, when the DI CD of the second portion in the first transparent electrode 10 is 5.4 μm, taking FI CD=DI CD-BIAS as an example, the FI CD of the second portion in the first transparent electrode 10 is 4.9 μm, that is, the line width of the second portion in the first transparent electrode 10 is 4.9 μm.

[0116] In one embodiment of the present disclosure, as shown in FIG6 , the thickness of the touch metal trace 11 is greater than the thickness of the first transparent electrode 10 to ensure the transmission effect of the touch metal trace 11 on the touch signal, thereby improving the touch sensitivity of the touch display panel.

[0117] In one embodiment of the present disclosure, the touch metal trace 11 includes a first metal layer, a second metal layer, and a third metal layer stacked in sequence along the base substrate 1 and pointing toward the first transparent electrode 10 .

[0118] When the touch metal traces 11 include different metal layers, the touch signal transmission effect of the touch metal traces 11 can be improved, thereby improving the touch sensitivity of the touch display panel, and reducing the manufacturing difficulty and improving the manufacturing efficiency.

[0119] It is worth noting that the touch metal trace 11 may also include only one metal layer or two metal layers, which can be specifically configured according to requirements and will not be described in detail here.

[0120] In one embodiment of the present disclosure, the first metal layer includes molybdenum, the second metal layer includes aluminum, and the third metal layer includes molybdenum. Of course, the metals in the first metal layer, the second metal layer, and the third metal layer can also be set to other metals as needed, and the details are not repeated here.

[0121] It is worth noting that during the formation of the touch metal traces 11, the second metal layer, which is aluminum, is easily side-etched, forming an undercut structure, so it needs to be effectively protected. In addition, if the third metal layer located on top of the touch metal traces is exposed during the preparation of the first transparent electrode 10, there is a risk of oxidation and shedding, so it also needs to be effectively protected. Accordingly, in the embodiment of the present disclosure, during the preparation of the touch display panel, the top and side surfaces of the touch metal traces 11 are covered with a photoresist pattern 12 to improve the product quality of the touch display panel.

[0122] In one example, the thickness of the first metal layer is The thickness of the second metal layer is The thickness of the third metal layer is The thickness of the first transparent electrode 10 is

[0123] It should be noted that the above thickness setting can ensure that each structural layer can effectively function and can effectively control the thickness of the touch display panel.

[0124] It is worth noting that the thickness of the first metal layer, the thickness of the second metal layer, the thickness of the third metal layer and the thickness of the first transparent electrode 10 can also be set to other values ​​according to needs, and the details will not be repeated here.

[0125] In one embodiment of the present disclosure, referring to the structure shown in FIG11 , the touch display panel further includes: a light-shielding structure 2, a buffer layer 3, an active structure 4, a gate insulating layer 5, a gate 6, a first metal structure 15, an interlayer dielectric layer 7, a source and drain 8, and a second metal structure 16. The light-shielding structure 2 is formed on one side of the base substrate 1 and is located in the display area 100 to shield the gate 6. The buffer layer 3 is formed on the side of the light-shielding structure 2 facing away from the base substrate 1, and the buffer layer 3 is laid in an entire layer. The buffer layer 3 can be made of materials such as silicon nitride and silicon oxide. While achieving the effect of blocking water and oxygen and blocking alkaline ions, it can also protect other structures on the base substrate 1.

[0126] The active structure 4 is formed on the side of the buffer layer 3 facing away from the base substrate 1 and is located in the display area 100. The gate insulation layer 5 is formed on the side of the active structure 4 facing away from the base substrate 1. The gate 6 is formed on the side of the gate insulation layer 5 facing away from the base substrate 1 and is located in the display area 100. The first metal structure 15 is formed on the side of the gate insulation layer 5 facing away from the base substrate 1. The first metal structure 15 and the gate 6 are fabricated on the same layer and are located in the fan-out area 200. It is worth noting that the first metal structure 15 is arranged parallel to the touch metal trace 11 and can also play a role in transmitting signals. Specifically, the first metal structure 15 can transmit touch signals to assist the touch metal trace 11 in signal transmission.

[0127] An interlayer dielectric layer 7 is formed on the side of the gate 6 and first metal structure 15 facing away from the base substrate 1. Source and drain electrodes 8 are formed on the side of the interlayer dielectric layer 7 facing away from the base substrate 1 and are located in the display area 100. Source and drain electrodes 8 are connected to the gate 6 through vias. A second metal structure 16 is formed on the side of the interlayer dielectric layer 7 facing away from the base substrate 1. The second metal structure 16 is fabricated on the same layer as the source and drain electrodes 8 and is located in the fan-out area 200. This second metal structure 16 is arranged parallel to the first metal structure 15 and the touch metal traces 11 and can also transmit signals. Specifically, this second metal structure 16 is used to transmit data signals.

[0128] FIG13 illustrates the metal wiring design within a touch display panel according to an embodiment of the present disclosure; FIG14 illustrates a plan view of the structure shown in FIG13 . As shown in FIG13 and FIG14 , a first metal structure 15 , a second metal structure 16 , and a touch metal trace 11 are arranged in parallel. The first metal structure 15 and the touch metal trace 11 can be used to transmit touch signals, and the second metal structure 16 can be used to transmit data signals. There can be multiple touch metal traces 11 , with the multiple touch metal traces 11 spaced apart. For example, the line width L1 of the touch metal trace 11 is 3.0 μm, and the spacing L2 between adjacent touch metal traces 11 is 5.4 μm.

[0129] Likewise, the line width L3 of the second metal structure 16 is 2.0 μm, and the interval L4 between adjacent second metal structures 16 is 2.2 μm. The line width L5 of the first metal structure 15 is 3.0 μm, and the interval L6 between adjacent second metal structures 16 is 5.4 μm.

[0130] It is worth noting that when the touch display panel provided in the embodiment of the present disclosure is a flexible panel, the provided base substrate 1 can be a flexible substrate such as polyimide (PI); when the touch display panel provided in the embodiment of the present disclosure is a rigid substrate, the base substrate 1 can be a rigid substrate such as glass and quartz.

[0131] In one embodiment of the present disclosure, as shown in Figures 11 and 12, the touch display panel provided by the present disclosure further includes: a storage capacitor dielectric layer formed on the side of the touch metal trace 11 facing away from the base substrate 1. The storage capacitor dielectric layer protects other structural layers at the bottom. The storage capacitor dielectric layer is (PVX), which can be understood as a passivation layer 13. Exemplarily, its material can be silicon nitride.

[0132] In one embodiment of the present disclosure, as shown in Figures 11 and 12 , the touch display panel provided by the present disclosure further includes a second transparent electrode 14 formed on a side of the storage capacitor dielectric layer facing away from the base substrate 1 , and the second transparent electrode 14 is connected to the drain electrode of the source / drain electrodes 8 through a via. It is worth noting that the second transparent electrode 14 is a pixel electrode.

[0133] It is understood that the second transparent electrode 14 and / or the first transparent electrode 10 are made of indium tin oxide. It is worth noting that the gate 6 can be made of a metal, an alloy, or a metal + alloy, specifically molybdenum, copper, titanium, aluminum, molybdenum nitride, etc. Molybdenum is used to improve the contact resistance with indium tin oxide.

[0134] Figure 15 illustrates the structure of a bonding region 300 of a touch display panel provided in an embodiment of the present disclosure. Specifically, a third metal structure 17 is provided within the bonding region 300, fabricated on the same layer as the gate electrode 6. An interlayer dielectric layer 7, a fourth metal structure 18, touch metal traces 11, and a second transparent electrode 14 are sequentially disposed on the third metal structure 17. The fourth metal structure 18 is fabricated on the same layer as the source and drain electrodes 8.

[0135] According to another aspect of the present disclosure, a touch display device is provided, including a touch display panel provided by any of the above technical solutions. The structures shown in FIG. 1 and FIG. 6 to FIG. 15 are referred to as the touch display device provided by the embodiments of the present disclosure.

[0136] In the touch display device provided by the embodiment of the present disclosure, the touch metal traces 11 in the touch display panel serve as traces for transmitting touch signals. The first transparent electrode 10 is located between the touch metal traces 11 and the base substrate 1, and the first transparent electrode 10 has a second portion added to the fan-out region 200 to protect the touch metal traces 11 during the manufacturing process. This allows the touch display panel provided by the present disclosure to be manufactured using fewer masks, thereby reducing the number of product ICs, ensuring the size of the display device, and saving the overall cost of the finished product.

[0137] When preparing the first transparent electrode 10 provided by the present disclosure, it is necessary to first form a material layer for the first transparent electrode 10 on the flat layer 9. In this case, the flat layer 9 can be completely covered by the material layer of the first transparent electrode 10. Then, a material layer for the touch metal trace 11 can be formed on the material layer of the first transparent electrode 10. This material layer of the touch metal trace 11 is patterned to form the touch metal trace 11. After the touch metal trace 11 is formed, the material layer of the first transparent electrode 10 is patterned to form the first transparent electrode 10.

[0138] It should be noted that in the touch display device provided by the embodiments of the present disclosure, the structural design of the touch display panel enables the flat layer 9 to complete the patterning process of the touch metal traces 11 without exposing the flat layer 9; thereafter, the patterning process of the first transparent electrode 10 is performed. Specifically, during the formation of the touch metal traces 11, the flat layer 9 is entirely covered by the material layer of the first transparent electrode 10. The flat layer 9 is not affected by the patterning process during the preparation of the touch metal traces 11. This can prevent the structure of the flat layer 9 from being damaged during the formation of the first transparent electrode 10, thereby preventing the emission of escaped gas. This further prevents the escaped gas from reacting with the metal layer within the touch metal traces 11, forming small black spots, and causing defects, thereby improving the display effect and yield of the touch display panel, and even the touch display device.

[0139] At the same time, the touch display panel utilizes a fan-out region 200 to design a pattern, so that the photoresist pattern 12 used to prepare the first transparent electrode 10 protects the touch metal trace 11. Specifically, by arranging the orthographic projection of the touch metal trace 11 on the base substrate 1 within the orthographic projection of the second portion of the first transparent electrode 10 on the base substrate 1, the touch display panel enables, during the process of patterning the material layer of the first transparent electrode 10 and forming the first transparent electrode 10, the mask used to prepare the first transparent electrode 10 can form a photoresist pattern 12 larger than the touch metal trace 11. The photoresist pattern 12 can cover the top and side surfaces of the touch metal trace 11, thereby preventing the metal in the touch metal trace 11 from reacting with the etching solution used to prepare the first transparent electrode 10, thereby preventing undercutting. This further improves the display effect and yield of the touch display panel, and even the touch display device.

[0140] Therefore, in the touch display device provided by the embodiment of the present disclosure, no additional IC is required in the touch display panel, the production cost of the touch display panel can be effectively controlled, and at the same time, the display effect and yield can be improved.

[0141] FIG16 is a flow chart of a method for manufacturing a touch display panel according to an embodiment of the present disclosure. Referring to the structure shown in FIG1 and FIG6 to FIG15 , and referring to the content shown in FIG16 , an embodiment of the present disclosure provides a method for manufacturing a touch display panel. The method for manufacturing a touch display panel includes:

[0142] Step S102: providing a base substrate 1;

[0143] Step S104: forming a flat layer 9 on the base substrate 1;

[0144] Step S106: depositing a preparation material layer of the first transparent electrode 10 on the flat layer 9;

[0145] Step S108 : forming a touch metal trace 11 on the preparation material layer of the first transparent electrode 10 , wherein the touch metal trace 11 is located in the fan-out area 200 ;

[0146] Step S1010: forming a photoresist layer on the touch metal trace 11, and controlling the patterned photoresist pattern 12 to cover the top surface and side surfaces of the touch metal trace 11 through a composition process;

[0147] Step S1012: forming the first transparent electrode 10 from the preparation material layer of the first transparent electrode 10 by a patterning process combined with the patterned photoresist pattern 12; the first transparent electrode 10 includes a first portion located in the display area 100 and a second portion located in the fan-out area 200;

[0148] Step S1014 : stripping the photoresist pattern 12 .

[0149] The method for preparing a touch display panel provided in the embodiments of the present disclosure separates the method for preparing the first transparent electrode 10 and places the preparation process of the metal trace pattern between the preparation processes of the first transparent electrode 10. Specifically, when preparing the first transparent electrode 10, it is necessary to first form a material layer for the first transparent electrode 10 on the flat layer 9. At this time, the flat layer 9 is completely covered by the material layer of the first transparent electrode 10. Then, as in step S108, a material layer for the touch metal trace 11 is formed on the material layer of the first transparent electrode 10, and the material layer of the touch metal trace 11 is patterned to form the touch metal trace 11. After the touch metal trace 11 is formed, step S1012 is performed to pattern the material layer of the first transparent electrode 10 to form the first transparent electrode 10.

[0150] It should be noted that the method for fabricating a touch display panel provided in the embodiments of the present disclosure allows the flat layer 9 to be patterned to form the touch metal traces 11 without exposing the flat layer 9; thereafter, the patterning process for the first transparent electrode 10 is performed. Specifically, during the formation of the touch metal traces 11, the flat layer 9 is entirely covered by the material layer of the first transparent electrode 10. The flat layer 9 is not affected by the patterning process in step S1012, thus preventing the structure of the flat layer 9 from being damaged during the formation of the first transparent electrode 10 and emitting escaped gases. This further prevents these escaped gases from reacting with the metal layer within the touch metal traces 11, forming small black spots, and causing defects, thereby improving the display quality and yield of the touch display panel.

[0151] It should be understood that the disclosed embodiment changes the pattern of the first transparent electrode 10. The first transparent electrode 10 includes a first portion and a second portion, with the first portion located in the display area 100 and the second portion located in the fan-out area 200. The second portion corresponds to the touch metal trace 11, which is used to transmit touch signals.

[0152] It is understood that a photoresist layer is used during patterning of the material layer of the first transparent electrode 10 through a patterning process (e.g., exposure and development). After patterning, the photoresist layer forms a photoresist pattern 12. The photoresist pattern 12 protects the touch metal trace 11 and forms the second portion of the material layer of the first transparent electrode 10 in a subsequent patterning process (etching).

[0153] Therefore, the method for fabricating a touch display panel provided in the embodiment of the present disclosure also utilizes a fan-out region 200 design pattern, so that the photoresist pattern 12 used to form the first transparent electrode 10 protects the touch metal trace 11. The photoresist pattern 12 can cover the top and side surfaces of the touch metal trace 11 to prevent the metal in the touch metal trace 11 from reacting with the etching solution used to form the first transparent electrode 10, thereby preventing the undercut phenomenon (marked by the dotted box) as shown in Figure 10, further improving the display quality and yield of the touch display panel.

[0154] Therefore, the manufacturing method provided by the embodiments of the present disclosure can produce a touch display panel using a smaller number of masks (fewer masks). Moreover, no additional IC is required in the touch display panel, which effectively controls the production cost of the touch display panel and improves the display effect and yield.

[0155] To better understand the method for fabricating a touch display panel provided by an embodiment of the present disclosure, the fabrication process for forming the first transparent electrode 10 and the touch metal traces 11 will now be described in detail. Specifically, when fabricating the first transparent electrode 10, the material layer for the first transparent electrode 10 must first be deposited (Dep). A mask corresponding to the first transparent electrode 10 must then be used. The mask must then be used to wet-etch (W / E) the material layer for the first transparent electrode 10 to form the first transparent electrode 10. Finally, the mask used to form the first transparent electrode 10 must be stripped. Similarly, when preparing to form the touch metal trace 11, first, it is necessary to deposit (Dep) the material layer of the touch metal trace 11; then, it is necessary to use a mask (Mask) corresponding to the touch metal trace 11; then, it is necessary to use the above-mentioned mask to wet-etch (W / E) the material layer of the touch metal trace 11 to form the touch metal trace 11; finally, it is necessary to strip (Strip) the mask forming the touch metal trace 11.

[0156] It is worth noting that if the pattern of the first transparent electrode 10 is not added to the fan-out region 200, according to the process shown in FIG17, after the deposition of the material layer of the first transparent electrode 10 is completed in FIG18A, the first transparent electrode 10 will be prepared first. After the first transparent electrode 10 is prepared, as shown in FIG18B, the first transparent electrode 10 does not exist in the fan-out region 200. After the touch metal trace 11 is prepared, as shown in FIG18C, the touch metal trace 11 is directly formed on the planar layer 9.

[0157] Compared to the structure shown in Figures 17 to 18C , if the pattern of the first transparent electrode 10 is added to the fan-out region 200, but the process of forming the first transparent electrode 10 first and then the touch metal traces 11 is still the same as in the flow diagram of Figure 17 , the planar layer 9, which serves as the organic film, is exposed in the hollows between the first transparent electrodes 10. This planar layer 9 is damaged by subsequent processes such as Descum (scum removal), Dep (deposition) of the material layer of the first transparent electrode 10, and Etch (etching) of the material layer of the first transparent electrode 10. When the structure of this planar layer 9 is damaged, it will emit escaped gases, which will react with the metal layer (e.g., aluminum) within the touch metal traces 11, resulting in small black spots across the entire touch display panel.

[0158] Since the process of destroying the PLN (flat layer 9) is a necessary process in this preparation method and cannot be skipped, and there is no significant improvement by adjusting the process parameters, the applicant proposed whether it is possible to complete the preparation process of the touch metal trace 11 without exposing the PLN (flat layer 9). Accordingly, as shown in Figure 19, the preparation method of the touch display panel provided by the embodiment of the present disclosure, when preparing the touch display panel with less mask, first performs the Dep process of the first transparent electrode 10, and forms a protection for the flat layer 9 through the material layer of the first transparent electrode 10, so that the flat layer 9 is not exposed; then, the Dep, Mask, W / E and Strip processes of the touch metal trace 11 are performed; after the preparation of the touch metal trace 11 is completed, the Mask, W / E and Strip processes of the first transparent electrode 10 are performed.

[0159] In addition, if there is no photoresist pattern 12 to protect the touch metal trace 11 during the preparation of the first transparent electrode 10 and the touch metal trace 11, when the material layer of the first transparent electrode 10 is wet-etched, the solution used for wet etching will corrode the metal layer (such as aluminum) within the touch metal trace 11. And because the first transparent electrode 10 has a hollow position, during annealing (CDA environment, 230°C for 25 minutes), the metal layer (such as Mo) on the top layer inside the touch metal trace 11 will be exposed, posing a risk of oxidation and peeling. After annealing, there is no Mo oxidation, but the TPM Top Mo is exposed, and the TPM Al will be corroded during ITO wet etching.

[0160] During the fabrication of a touch display panel, if the touch metal trace 11 is fabricated before the first transparent electrode 10, the metal layer (e.g., aluminum) within the touch metal trace 11 will be corroded during wet etching when the first transparent electrode 10 is formed. Therefore, the touch metal trace 11 can only be fabricated after the first transparent electrode 10 is fabricated.

[0161] It is worth noting that the method for preparing the touch display panel provided in the embodiment of the present disclosure can also be used to prepare the touch display panel provided in the above disclosed embodiments, and the details will not be repeated here.

[0162] In one embodiment of the present disclosure, a method for controlling the patterned photoresist pattern 12 to cover the top surface and side surfaces of the touch metal trace 11 through a patterning process includes:

[0163] Providing a photomask, and aligning the first pattern of the photomask with the touch metal trace 11;

[0164] Through exposure and development processes, a photoresist pattern 12 is obtained in the fan-out region 200 , so that the photoresist pattern 12 covers the top surface and side surfaces of the touch metal trace 11 , thereby forming a structure as shown in FIG. 9 .

[0165] It should be understood that the photomask in the touch display panel provided in the embodiment of the present disclosure is used to prepare the first transparent electrode 10 , and the structure of the photomask is different from that of the photomask used to prepare the first transparent electrode 10 in the related art.

[0166] Specifically, in the disclosed embodiment, the photomask forms a first pattern at a location corresponding to the fan-out region 200. Through this first pattern, the photoresist layer located on the surface of the touch metal trace 11 can form a photoresist pattern 12. This photoresist pattern 12 protects the touch metal trace 11 and is used to form the second sub-portion within the first transparent electrode 10.

[0167] It should be noted that, since the photoresist pattern 12 can protect the touch metal trace 11 , when etching the material layer of the first transparent electrode 10 , the etching solution will not react with the touch metal trace 11 , and thus no undercut structure will be generated.

[0168] In one embodiment of the present disclosure, the orthographic projection of the first pattern of the mask on the base substrate 1 covers the orthographic projection of the touch metal trace 11 on the base substrate 1 .

[0169] It is understandable that, since the photoresist pattern 12 protects the touch metal trace 11 , the orthographic projection of the prepared touch metal trace 11 on the base substrate 1 is located within the orthographic projection of the second portion of the first transparent electrode 10 on the base substrate 1 .

[0170] Considering the alignment issues between film layers during the fabrication of a touch display panel, to prevent the photoresist pattern 12 from failing to fully cover the touch metal trace 11, in one embodiment of the present disclosure, half of the difference between the line width of the second portion and the line width of the touch metal trace 11 is greater than half the distance between the center of the line width of the second portion and the center of the line width of the touch metal trace 11. It should be noted that this structural arrangement ensures that the touch metal trace 11 is effectively covered by the photoresist pattern 12 even when the film layers shift during fabrication.

[0171] In addition, the mask CD of the second portion within the first transparent electrode 10 can also be defined. It is understood that the mask CD is the line width design value of the second portion. In one embodiment of the present disclosure, the line width design value of the second portion is greater than a minimum value, which is the minimum value = the critical dimension of the touch metal trace 11 + the alignment deviation margin between two adjacent layers caused by the equipment used + the BIAS of the first transparent electrode 10 + the overexposure of the first transparent electrode 10;

[0172] The BIAS of the first transparent electrode 10 = |the critical dimension of the first transparent electrode 10 - the critical dimension of the photoresist pattern 12 covering the touch metal trace 11 |.

[0173] It is understood that the critical dimension of the first transparent electrode 10 is the dimension x1 of the first transparent electrode 10 shown in FIG6 , and the critical dimension of the photoresist pattern 12 covering the touch metal trace 11 is the dimension x2 of the photoresist pattern 12 shown in FIG9 . Therefore, the BIAS of the first transparent electrode 10 = |x1-x2|.

[0174] It's worth noting that in the above formula, the photoresist pattern 12 refers to the photoresist pattern 12 used to form the second portion of the first transparent electrode 10. The overexposure of the first transparent electrode 10 is set by the operator during the touch display panel manufacturing process. In a 1:1 exposure, the critical dimension of the second portion (DI CD) equals the designed line width of the second portion (MASK CD). In non-1:1 exposure, there's a difference in overexposure between the two.

[0175] It should be noted that by setting the above formula, the photoresist pattern 12 can effectively cover the top and side surfaces of the touch metal traces 11 to effectively protect the touch metal traces 11 and thereby improve the product quality of the resulting touch display panel.

[0176] For example, let's assume the critical dimension of the touch metal trace 11 is 3.0μm, the BIAS of the first transparent electrode 10 is 0.5μm, the alignment margin between two adjacent layers caused by the equipment is 1.89, and 1:1 exposure is used. In this case, the overexposure of the first transparent electrode 10 is equal to 0. From the above values, we can calculate: 3.0 + 1.89 + 0.5 ≈ 5.4μm, that is, the minimum value is approximately equal to 5.4μm.

[0177] It is worth noting that when the MASK CD of the second portion in the first transparent electrode 10 is 5.4 μm, that is, when the DI CD of the second portion in the first transparent electrode 10 is 5.4 μm, taking FI CD=DI CD-BIAS as an example, the FI CD of the second portion in the first transparent electrode 10 is 4.9 μm, that is, the line width of the second portion in the first transparent electrode 10 is 4.9 μm.

[0178] In one embodiment of the present disclosure, the thickness of the touch metal trace 11 is greater than the thickness of the first transparent electrode 10 to ensure the touch signal transmission effect of the touch metal trace 11, thereby improving the touch sensitivity of the touch display panel.

[0179] In addition, the applicant also evaluated the process of fabricating the touch metal trace 11 first and then the first transparent electrode 10. As shown in Figure 20, if the touch metal trace 11 is fabricated first and then the first transparent electrode 10, Figures 21A to 21C are schematic diagrams of the film layer changes within the display area 100 when the touch metal trace 11 is fabricated using the process in Figure 20; Figures 22A to 22C are schematic diagrams of the film layer changes within the fan-out area 200 when the touch metal trace 11 is fabricated using the process in Figure 20; and Figures 23A to 23C are schematic diagrams of the film layer changes within the bonding area 300 when the touch metal trace 11 is fabricated using the process in Figure 20. During the verification process, it was found that the touch metal trace 11 was exposed and showed no Mo oxidation after Annealing. However, during the actual verification process, it was found that since the thickness of the first transparent electrode 10 is less than the thickness of the touch metal trace 11, the first transparent electrode 10 cannot effectively cover the touch metal trace 11, and it is very easy to break at the profile position of the touch metal trace 11. Therefore, this solution is not feasible.

[0180] Therefore, the method for preparing the touch display panel provided in the embodiment of the present disclosure, which includes completing the preparation process of the touch metal trace 11 without exposing the flat layer 9 behind the first transparent electrode 10Dep, and then performing the processes of coating, exposing, developing, and etching the first transparent electrode 10, is still the best and only improvement solution.

[0181] In one embodiment of the present disclosure, the touch metal trace 11 includes a first metal layer, a second metal layer, and a third metal layer stacked in sequence along the base substrate 1 and pointing toward the first transparent electrode 10 .

[0182] When the touch metal traces 11 include different metal layers, the touch signal transmission effect of the touch metal traces 11 can be improved, thereby improving the touch sensitivity of the touch display panel, and reducing the manufacturing difficulty and improving the manufacturing efficiency.

[0183] It is worth noting that the touch metal trace 11 may also include only one metal layer or two metal layers, which can be specifically configured according to requirements and will not be described in detail here.

[0184] In one embodiment of the present disclosure, the first metal layer includes molybdenum, the second metal layer includes aluminum, and the third metal layer includes molybdenum. Of course, the metals in the first metal layer, the second metal layer, and the third metal layer can also be set to other metals as needed, and the details are not repeated here.

[0185] It is worth noting that during the formation of the touch metal traces 11, the second metal layer, which is aluminum, is easily side-etched, forming an undercut structure, so it needs to be effectively protected. In addition, if the third metal layer located on top of the touch metal traces is exposed during the preparation of the first transparent electrode 10, there is a risk of oxidation and shedding, so it also needs to be effectively protected. Accordingly, in the embodiment of the present disclosure, during the preparation of the touch display panel, the top and side surfaces of the touch metal traces 11 are covered with a photoresist pattern 12 to improve the product quality of the touch display panel.

[0186] In one embodiment of the present disclosure, the thickness of the first metal layer is The thickness of the second metal layer is The thickness of the third metal layer is The thickness of the first transparent electrode 10 is

[0187] It should be noted that the above thickness setting can ensure that each structural layer can effectively function and can effectively control the thickness of the touch display panel.

[0188] In one embodiment of the present disclosure, before forming the planar layer 9 on the base substrate 1, the preparation method provided by the embodiment of the present disclosure further includes:

[0189] forming a light shielding structure 2 on a portion of the base substrate 1 located in the display area 100;

[0190] A buffer layer 3 is formed on the light shielding structure 2, and the buffer layer 3 is located in the display area 100 and the fan-out area 200;

[0191] forming an active structure 4 on a portion of the buffer layer 3 located in the display area 100;

[0192] A gate insulating layer 5 is formed on the active structure 4, and the gate insulating layer 5 is located in the display area 100 and the fan-out area 200;

[0193] A gate 6 and a first metal structure 15 are formed on the gate insulating layer 5 , wherein the gate 6 is located in the display area 100 , and the first metal structure 15 is located in the fan-out area 200 ;

[0194] forming an interlayer dielectric layer 7 on the gate 6 and the first metal structure 15;

[0195] A source / drain electrode 8 and a second metal structure 16 are formed on the interlayer dielectric. The source / drain electrode 8 is located in the display area 100 and is connected to the gate 6 through vias. The second metal structure 16 is located in the fan-out area 200 .

[0196] The buffer layer 3 can be made of materials such as silicon nitride and silicon oxide, and can achieve the effect of blocking water, oxygen and alkaline ions while also protecting other structures on the base substrate 1.

[0197] The first metal structure 15 is arranged parallel to the touch metal trace 11 and can also transmit signals. Specifically, the first metal structure 15 can transmit touch signals to assist the touch metal trace 11 in signal transmission. The second metal structure 16 is arranged parallel to the first metal structure 15 and the touch metal trace 11 and can also transmit signals. Specifically, the second metal structure 16 is used to transmit data signals.

[0198] It is worth noting that when the touch display panel provided in the embodiment of the present disclosure is a flexible panel, the provided base substrate 1 can be a flexible substrate such as polyimide; when the touch display panel provided in the embodiment of the present disclosure is a rigid substrate, the base substrate 1 can be a rigid substrate such as glass and quartz.

[0199] In one embodiment of the present disclosure, the method for manufacturing a touch display panel provided in the embodiment of the present disclosure further includes: forming a storage capacitor dielectric layer on the touch metal trace 11. The storage capacitor dielectric layer protects other underlying structural layers and can be understood as a passivation layer 13. Exemplarily, the material of the storage capacitor dielectric layer can be silicon nitride.

[0200] In one embodiment of the present disclosure, the method for manufacturing a touch display panel provided by the embodiment of the present disclosure further includes: forming a second transparent electrode (PITO) 14 on the storage capacitor dielectric layer, wherein the second transparent electrode 14 is connected to the drain electrode of the source and drain electrodes 8 through a via. It is worth noting that the second transparent electrode 14 is a pixel electrode.

[0201] It is understood that the second transparent electrode 14 and / or the first transparent electrode 10 are made of indium tin oxide. It is worth noting that the gate 6 can be made of a metal, an alloy, or a metal + alloy, specifically molybdenum, copper, titanium, aluminum, molybdenum nitride, etc. Molybdenum is used to improve the contact resistance with indium tin oxide.

[0202] In order to more clearly understand the touch display panel provided by the embodiment of the present disclosure, the use process of the 10-layer mask of the touch display panel is now specifically introduced.

[0203] Please refer to Figure 11 in conjunction with Figure 6. As an example, when forming the shading structure 2, the first mask is required; when forming the active structure 4, the second mask is required; when forming the gate 6, the third mask is required; after the interlayer dielectric layer 7, the fourth mask is required to form a via on the interlayer dielectric layer 7 so that the source and drain electrodes 8 are connected to the active structure 4 through the via; when forming the source and drain electrodes 8, the fifth mask is required; after forming the flat layer 9, the sixth mask is required; when forming the material layer of the first transparent electrode 10 and preparing the touch metal trace 11, the seventh mask is required; after forming the touch metal trace 11, the eighth mask is required to form the first transparent electrode 10; after forming the passivation layer 13, the ninth mask is required to form a via so that the second transparent electrode 14 is connected to the drain in the source and drain electrodes 8; and when forming the second transparent electrode 14, the tenth mask is required.

[0204] It should be noted that although the steps of the method for manufacturing a display panel in the present disclosure are described in a specific order in the accompanying drawings, this does not require or imply that the steps must be performed in this specific order, or that all steps must be performed to achieve the desired results. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0205] Other embodiments of the present disclosure will readily occur to those skilled in the art after considering the specification and practicing the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only, with the true scope and spirit of the present disclosure being indicated by the appended claims.

Claims

1. A touch display panel, characterized in that: include: A display area and a fan-out area, wherein the fan-out area is located on one side of the display area; The touch display panel includes: substrate; a flat layer formed on one side of the base substrate; A first transparent electrode is formed on a side of the planar layer facing away from the base substrate; the first transparent electrode includes a first portion located in the display area and a second portion located in the fan-out area; A touch metal trace is formed on a side of the first transparent electrode facing away from the base substrate and located in the fan-out area. The orthographic projection of the touch metal trace on the base substrate is located within the orthographic projection of the second portion of the first transparent electrode on the base substrate.

2. The touch display panel according to claim 1, wherein: Half of the difference between the line width of the second portion and the line width of the touch metal trace is greater than half of the distance between the center of the line width of the second portion and the center of the line width of the touch metal trace.

3. The touch display panel according to claim 1 or 2, wherein: The thickness of the touch metal wiring is greater than the thickness of the first transparent electrode.

4. The method for preparing a touch display panel according to claim 3, wherein: The touch metal trace includes a first metal layer, a second metal layer, and a third metal layer stacked in sequence along the base substrate and pointing toward the first transparent electrode.

5. The method for preparing a touch display panel according to claim 4, wherein: The first metal layer includes molybdenum; the second metal layer includes aluminum; and the third metal layer includes molybdenum.

6. The touch display panel according to claim 1 or 2, wherein: The touch display panel also includes: a light shielding structure formed on one side of the base substrate and located in the display area; a buffer layer formed on a side of the light-shielding structure facing away from the base substrate; an active structure formed on a side of the buffer layer facing away from the base substrate and located in the display area; a gate insulating layer, formed on a side of the active structure facing away from the substrate; a gate electrode formed on a side of the gate insulating layer facing away from the base substrate, and the gate electrode is located in the display area; a first metal structure formed on a side of the gate insulating layer facing away from the base substrate, and the first metal structure is prepared in the same layer as the gate and is located in the fan-out region; an interlayer dielectric layer, formed on a side of the gate and the first metal structure facing away from the substrate; Source and drain electrodes are formed on a side of the interlayer dielectric layer away from the base substrate and located in the display area, and the source and drain electrodes are connected to the gate through vias; The second metal structure is formed on a side of the interlayer dielectric layer away from the base substrate, and the second metal structure is prepared in the same layer as the source and drain and is located in the fan-out area.

7. The touch display panel according to claim 6, wherein: Also includes: The storage capacitor dielectric layer is formed on a side of the touch metal trace facing away from the base substrate.

8. The touch display panel according to claim 7, wherein: Also includes: A second transparent electrode is formed on a side of the storage capacitor dielectric layer away from the base substrate, and the second transparent electrode is connected to the drain electrode of the source and drain electrodes through a via hole.

9. A touch display device, characterized in that: It comprises the touch display panel according to any one of claims 1 to 8.

10. A method for manufacturing a touch display panel, wherein the touch display panel comprises a display area and a fan-out area, wherein the fan-out area is located on one side of the display area, wherein: The preparation method comprises: providing a substrate; forming a planar layer on the base substrate; Depositing a first transparent electrode preparation material layer on the flat layer; forming a touch metal trace on the preparation material layer of the first transparent electrode, wherein the touch metal trace is located in the fan-out area; forming a photoresist layer on the touch metal trace, and controlling the patterned photoresist pattern to cover the top surface and side surfaces of the touch metal trace through a composition process; The first transparent electrode is formed into a first transparent electrode by combining the patterned photoresist pattern with the preparation material layer of the first transparent electrode through a composition process; the first transparent electrode includes a first portion located in the display area and a second portion located in the fan-out area; The photoresist pattern is stripped.

11. The method for manufacturing a touch display panel according to claim 10, wherein: The method of controlling the patterned photoresist pattern to cover the top surface and side surfaces of the touch metal trace through a composition process includes: Providing a mask, and aligning a first pattern of the mask with the touch metal trace; The photoresist pattern is obtained in the fan-out area through exposure and development processes, so that the photoresist pattern covers the top surface and side surfaces of the touch metal trace.

12. The method for manufacturing a touch display panel according to claim 11, wherein: The orthographic projection of the first pattern of the mask on the base substrate covers the orthographic projection of the touch metal trace on the base substrate.

13. The method for manufacturing a touch display panel according to claim 12, wherein: Half of the difference between the line width of the second portion and the line width of the touch metal trace is greater than half of the distance between the center of the line width of the second portion and the center of the line width of the touch metal trace.

14. The method for preparing a touch display panel according to any one of claims 10 to 13, wherein: The thickness of the touch metal wiring is greater than the thickness of the first transparent electrode.

15. The method for manufacturing a touch display panel according to claim 14, wherein: The touch metal trace includes a first metal layer, a second metal layer, and a third metal layer stacked in sequence along the base substrate and pointing toward the first transparent electrode.

16. The method for manufacturing a touch display panel according to claim 15, wherein: The first metal layer includes molybdenum; the second metal layer includes aluminum; and the third metal layer includes molybdenum.

17. The method for preparing a touch display panel according to any one of claims 10 to 13, wherein: Before forming the flat layer on the base substrate, the preparation method further includes: forming a light shielding structure on a portion of the base substrate located in the display area; forming a buffer layer on the light-shielding structure, wherein the buffer layer is located in the display area and the fan-out area; forming an active structure on a portion of the buffer layer located in the display area; forming a gate insulating layer on the active structure, wherein the gate insulating layer is located in the display area and the fan-out area; forming a gate and a first metal structure on the gate insulating layer, wherein the gate is located in the display area and the first metal structure is located in the fan-out area; forming an interlayer dielectric layer on the gate and the first metal structure; A source / drain and a second metal structure are formed on the interlayer dielectric. The source / drain are located in the display area and connected to the gate through vias. The second metal structure is located in the fan-out area.

18. The method for manufacturing a touch display panel according to claim 17, wherein: The preparation method further includes: forming a storage capacitor dielectric layer on the touch metal trace.

19. The method for manufacturing a touch display panel according to claim 18, wherein: The manufacturing method further includes: forming a second transparent electrode on the storage capacitor dielectric layer, wherein the second transparent electrode is connected to the drain electrode of the source and drain electrodes through a via hole.

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