A flexible display substrate and a method for preparing the same, and a flexible display device

Abstract

The embodiment of the present invention provides a flexible display substrate and a preparation method thereof, and a flexible display device, which relates to the field of display technology and solves the problem of metal traces on the flexible display substrate being broken when the IC is crimped on the flexible display substrate. The flexible display substrate includes a binding area, the binding area includes a Pad area, and the binding area of ​​the flexible display substrate includes: a plurality of conductive terminals and a stress release layer sequentially arranged on a flexible substrate; wherein the stress release layer is partially hollowed out in the Pad area to expose the conductive terminal; and the conductive terminal is connected to the metal traces in the display area. It is used to prevent the deformation of the flexible display substrate.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a flexible display substrate and a preparation method thereof, and a flexible display device. Background Art

[0002] In recent years, flexible display substrates have been increasingly widely used in electronic devices due to their good impact resistance, lightness, and thinness. Display devices using flexible display substrates include liquid crystal display devices (LCD), organic light-emitting display devices (OLED), and electrophoretic display devices.

[0003] The IC (Integrated Circuit) in the existing flexible display device is generally bound by COF (Chip On Film), that is, the IC is first bonded to the flexible circuit board, and then the flexible circuit board bound with the IC is pressed onto the display panel. Since the flexible circuit board is made of soft material, the IC will not break the circuit of the array substrate of the display panel when it is pressed. However, due to the high cost of COF and the fact that the circuit of COF cannot be made too thin, COF cannot be used on high-resolution products. Based on this, the COP (Chip on plastic, directly binding the IC to the display panel) binding method has become the future development direction. However, due to the high hardness of the IC, direct pressing will cause the IC to sink, thereby causing the metal traces of the flexible display substrate to break. For example Figure 1 As shown, since the flexible display substrate 10 is generally soft, the flexible display substrate 10 is usually attached to the protective substrate 20 through the adhesive 30. When the IC is pressed against the flexible display substrate 10, the conductive pattern (IC bump) 40 on the IC is connected to the conductive terminal ( Figure 1 When the conductive pattern 40 is connected to the substrate 10 (not shown in the figure), the adhesive material 30 located under the conductive pattern 40 will flow toward the periphery and fill the area between the conductive patterns 40, which will cause the flexible display substrate 10 to warp, thereby causing the metal traces on the flexible display substrate 10 to break. Summary of the invention

[0004] The embodiments of the present invention provide a flexible display substrate and a method for preparing the same, and a flexible display device, which solve the problem of metal wiring breakage on the flexible display substrate caused by crimping an IC on the flexible display substrate.

[0005] To achieve the above object, the embodiments of the present invention adopt the following technical solutions:

[0006] In a first aspect, a flexible display substrate is provided, comprising a binding area, wherein the binding area comprises a Pad area, and the binding area of ​​the flexible display substrate comprises: a plurality of conductive terminals and a stress release layer sequentially arranged on a flexible substrate; wherein a portion of the stress release layer located in the Pad area is hollowed out to expose the conductive terminal; and the conductive terminal is connected to a metal trace of a display area.

[0007] Preferably, the material of the stress release layer includes inorganic material.

[0008] Further preferably, the material of the stress release layer is selected from at least one of silicon nitride, silicon oxide or silicon oxynitride.

[0009] Preferably, the thickness of the stress release layer is 0.1-1.0 μm.

[0010] Preferably, the flexible display substrate further comprises an encapsulation layer located in the display area; the stress release layer and at least one layer of the encapsulation layer are of the same layer and material.

[0011] Further preferably, the encapsulation layer includes a first inorganic layer, a second inorganic layer, and an organic layer arranged between the first inorganic layer and the second inorganic layer; the stress release layer is in the same layer and material as the first inorganic layer or the second inorganic layer; or, the stress release layer includes a first sub-stress release layer and a second sub-stress release layer arranged in a stacked manner, the first sub-stress release layer is in the same layer and material as the first inorganic layer, and the second sub-stress release layer is in the same layer and material as the second inorganic layer.

[0012] Preferably, the flexible display substrate also includes a flat layer and a touch layer arranged on the flat layer; the touch layer includes a first touch electrode layer, a second touch electrode layer and an insulating layer arranged between the first touch electrode layer and the second touch electrode layer; the stress release layer is in the same layer and material as the flat layer or the insulating layer; or, the stress release layer includes a first sub-stress release layer and a second sub-stress release layer arranged in a stacked manner, the first sub-stress release layer is in the same layer and material as the flat layer, and the second sub-stress release layer is in the same layer and material as the insulating layer.

[0013] Further preferably, the flexible display substrate also includes a first connection pattern arranged on a side of the conductive terminal away from the flexible base substrate, the first connection pattern being connected to the conductive terminal; the first connection pattern is on the same layer and material as the first touch electrode layer or the second touch electrode layer; or, the first connection pattern includes a first sub-connection pattern and a second sub-connection pattern arranged in a stacked manner, the first sub-connection pattern is on the same layer and material as the first touch electrode layer, and the second sub-connection pattern is on the same layer and material as the second touch electrode layer.

[0014] Preferably, the flexible display substrate further comprises a second connection pattern disposed between the conductive terminal and the stress release layer, and the second connection pattern is connected to the conductive terminal.

[0015] Further preferably, the metal routing is a gate line, the conductive terminal is in the same layer and material as the gate line, and the second connection pattern is in the same layer and material as the data line; or, the metal routing is a data line, the conductive terminal is in the same layer and material as the data line, and the second connection pattern is in the same layer and material as the gate line.

[0016] In a second aspect, a flexible display device is provided, comprising the above-mentioned flexible display substrate and an IC; the IC comprises a conductive pattern; wherein the conductive pattern of the IC is crimped to the conductive terminal of the flexible display substrate.

[0017] Preferably, the projection of the conductive pattern on the flexible substrate is located within the projection of the boundary of the hollow region of the stress release layer on the flexible substrate.

[0018] In a third aspect, a method for preparing a flexible display substrate is provided, comprising a binding area, wherein the binding area includes a Pad area, comprising: forming a plurality of conductive terminals located in the binding area on a flexible substrate; forming a stress release layer located in the binding area on the conductive terminals, wherein a portion of the stress release layer located in the Pad area is hollowed out to expose the conductive terminals.

[0019] Preferably, the preparation method also includes: forming an encapsulation layer on the conductive terminal; forming the stress release layer and forming the encapsulation layer, specifically including: forming a first inorganic pattern layer including a first inorganic layer on the conductive terminal; forming an organic layer on the first inorganic layer; forming a second inorganic pattern layer including a second inorganic layer on the organic layer; wherein the first inorganic pattern layer also includes: a first sub-stress release layer located in the binding area; and / or the second inorganic pattern layer also includes: a second sub-stress release layer located in the binding area; the stress release layer includes the first sub-stress release layer and / or the second sub-stress release layer, and the encapsulation layer includes the first inorganic layer, the organic layer and the second inorganic layer.

[0020] Preferably, the preparation method also includes: forming an encapsulation layer on the conductive terminal; forming the stress release layer and forming the encapsulation layer, specifically including: forming a first inorganic pattern layer including a first inorganic layer on the conductive terminal; forming an organic layer on the first inorganic layer; forming a second inorganic pattern layer including a second inorganic layer on the organic layer; the first inorganic pattern layer also includes: a third inorganic layer located in the binding area, the third inorganic layer is patterned to form a first sub-stress release layer; and / or the second inorganic pattern layer also includes: a fourth inorganic layer located in the binding area, the fourth inorganic layer is patterned to form a second sub-stress release layer; wherein the stress release layer includes the first sub-stress release layer and / or the second sub-stress release layer; the encapsulation layer includes the first inorganic layer, the organic layer and the second inorganic layer.

[0021] The embodiments of the present invention provide a flexible display substrate and a preparation method thereof, and a flexible display device. The flexible display substrate includes a plurality of conductive terminals and a stress release layer arranged on the conductive terminals. Since a portion of the stress release layer located in the pad area is hollowed out to expose the conductive terminals, after the flexible base substrate and the protective substrate are bonded by adhesive, when the conductive pattern of the IC and the flexible display substrate are crimped to connect the conductive pattern on the IC with the conductive terminal, although the adhesive under the conductive pattern will flow to the area between the conductive patterns, since the stress release layer is arranged on the flexible display substrate, the stress release layer can offset the force generated by the adhesive toward the stress release layer, so the stress release layer can release stress and prevent the binding area of ​​the flexible display substrate from warping, thereby avoiding problems such as metal wiring breakage caused by deformation of the flexible display substrate, poor contact of the metal wiring, and short circuit caused by aggregation of conductive particles. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 A schematic diagram of a structure in which a flexible display substrate and a protective substrate are bonded together by adhesive material provided in the prior art;

[0024] Figure 2 A schematic diagram of a structure of a flexible display substrate area division provided by an embodiment of the present invention;

[0025] Figure 3 A schematic diagram of a structure of a flexible display substrate binding area provided by an embodiment of the present invention Figure 1 ;

[0026] Figure 4 for Figure 3 A cross-sectional schematic diagram along the BB' direction;

[0027] Figure 5 for Figure 3 Schematic cross-sectional view along the AA' direction;

[0028] Figure 6 A schematic diagram of the structure of an encapsulation layer provided in an embodiment of the present invention;

[0029] Figure 7 A schematic diagram of a structure of a flexible display substrate binding area provided by an embodiment of the present invention Figure 2 ;

[0030] Figure 8 A schematic structural diagram of a flexible display substrate including a touch layer and a flat layer provided in an embodiment of the present invention;

[0031] Fig. 9 A schematic diagram of a structure of a flexible display substrate binding area provided by an embodiment of the present invention Figure 3 ;

[0032] Fig.10 A schematic diagram of a structure of a flexible display substrate binding area provided by an embodiment of the present invention Figure 4 ;

[0033] Fig.11 A schematic diagram of a structure of a flexible display substrate binding area provided by an embodiment of the present invention Figure 5 ;

[0034] Fig.12 A schematic structural diagram of a flexible display device provided by an embodiment of the present invention;

[0035] Fig.13 A schematic flow chart of a method for preparing a flexible display substrate provided in an embodiment of the present invention.

[0036] Reference numerals:

[0037] 01-display area; 02-non-display area; 03-binding area; 04-Pad area; 10-flexible display substrate; 20-protective substrate; 30-glue; 40-conductive pattern; 50-flexible substrate; 60-conductive terminal; 601-metal routing lead; 70-stress release layer; 80-packaging layer; 801-first inorganic layer; 802-second inorganic layer; 803-organic layer; 90-buffer layer; 100-second connection pattern; 110-intermediate dielectric layer; 120-IC; 130-printed circuit board; 140-flat layer; 150-touch layer; 1501-first touch electrode layer; 1502-second touch electrode layer; 1503-insulating layer; 160-first connection pattern. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] The flexible display substrate 10 is as follows Figure 2 As shown, it is divided into a display area 01 and a non-display area 02, and a binding area 03 of the non-display area 02 includes a pad area 04. The area in the non-display area 02 for binding the IC is called the binding area 03, wherein the area in the binding area 03 where the IC is connected to the flexible display substrate wiring is called the pad area 04.

[0040] The binding area of ​​the flexible display substrate 10 is provided with conductive terminals. When the IC is crimped with the flexible display substrate 10, the conductive pattern 40 on the IC will be connected with the conductive terminals on the flexible display substrate 10 to input the signal on the IC to the conductive terminals or output the signal on the conductive terminals to the IC. Figure 3 As shown, each conductive terminal 60 in the binding area 03 is connected to a metal routing lead 601, and the metal routing lead 601 is connected to the metal routing of the display area. In this way, the signal on the metal routing can be input to the conductive terminal 60, or the signal on the conductive terminal 60 can also be input to the metal routing.

[0041] The embodiment of the present invention provides a flexible display substrate 10, such as Figure 4 and Figure 5As shown, the binding area 03 of the flexible display substrate 10 includes: a plurality of conductive terminals 60 and a stress release layer 70 sequentially arranged on the flexible base substrate 50; wherein, the stress release layer 70 is located in a portion of the Pad area 04 which is hollowed out to expose the conductive terminal 60; and the conductive terminal 60 is connected to the metal trace of the display area 01.

[0042] It should be noted that, first, since the stress release layer 70 is partially hollowed out in the Pad region 04 to expose the conductive terminal 60, when the IC is pressed against the flexible display substrate 10, Figure 4 and Figure 5 As shown, the conductive pattern 40 on the IC passes through the hollow area of ​​the stress release layer 70 and is connected to the conductive short-circuit 60 .

[0043] Second, the material of the flexible substrate 50 is not limited, and may be PI (Polyimide), for example.

[0044] Third, the material of the stress release layer 70 is not limited, and can be an organic material or an inorganic material. Since the function of the stress release layer 70 is to release stress and inhibit deformation of the flexible display substrate 10, those skilled in the art should understand that the material for preparing the stress release layer 70 should have a large hardness, be not easily deformed, and have a large elastic modulus.

[0045] On this basis, the stress release layer 70 can be manufactured simultaneously with the film layer of the flexible display substrate 10 itself, or can be manufactured separately in the binding area 03, which is not limited.

[0046] Fourth, the flexible display substrate 10 provided in the embodiment of the present invention may be provided with a protective substrate 20; or it may not be provided with a protective substrate 20. When the flexible display substrate 10 in the embodiment of the present invention is provided with a protective substrate 20, the protective substrate 20 and the flexible base substrate 50 are bonded together by means of a glue material 30; wherein the hardness of the protective substrate 20 is greater than the hardness of the flexible base substrate 50.

[0047] Here, both the protective substrate 20 and the flexible substrate 50 are flexible substrates, but the hardness of the protective substrate 20 is greater than that of the flexible substrate 50. The material of the protective substrate 20 is not limited, and may be PET (Polyethylene terephthalate), for example.

[0048] In addition, when the flexible display substrate includes the protective substrate 20, when the flexible display substrate 10 is manufactured, the flexible base substrate 50 can be first formed on a rigid substrate (such as glass), and then a display device can be formed on the flexible base substrate 50. After the display device is manufactured, the flexible base substrate 50 and the rigid substrate are peeled off. After that, the flexible base substrate 50 with the display device and the protective substrate 20 are bonded together by the adhesive 30 to obtain a flexible display substrate with the protective substrate 20.

[0049] Fifth, the flexible display substrate 10 provided in the embodiment of the present invention may be a display substrate or a display panel.

[0050] An embodiment of the present invention provides a flexible display substrate 10, which includes a plurality of conductive terminals 60 and a stress release layer 70 disposed on the conductive terminals 60. Since the portion of the stress release layer 70 located in the Pad area 04 is hollowed out to expose the conductive terminals 60, after the flexible base substrate 50 and the protective substrate 20 are bonded by the adhesive 30, when the IC is crimped with the conductive pattern 40 of the flexible display substrate 10 to connect the conductive pattern 40 on the IC with the conductive terminal 60, although the adhesive 30 under the conductive pattern 40 will flow to the area between the conductive patterns 40, since the stress release layer 70 is disposed on the flexible display substrate 10, the stress release layer 70 can offset the force generated by the adhesive 30 toward the stress release layer 70, so that the stress release layer 70 can release stress and prevent the binding area of ​​the flexible display substrate 10 from warping, thereby avoiding problems such as metal trace breakage caused by deformation of the flexible display substrate 10, poor contact of the metal trace, and short circuit caused by aggregation of conductive particles.

[0051] On this basis, since the stress release layer 70 covers the binding area 03 , it can prevent water vapor, oxygen, etc. from corroding the binding area 03 and prevent metal particles from entering the binding area 03 to affect the binding reliability of the binding area 03 .

[0052] Compared with organic materials, inorganic materials generally have a larger elastic modulus, higher hardness, and are less likely to deform. Therefore, in the embodiment of the present invention, the material of the stress release layer 70 preferably includes inorganic materials.

[0053] Here, there is no limitation on what kind of inorganic material is used, and the stress release layer 70 is preferably made of an inorganic material with high hardness. x ), silicon oxide (SiO x ) and silicon oxynitride (SiO x O y) has a higher hardness, a larger elastic modulus, and its intrinsic stress (internal stress) is compressive stress. Therefore, in an embodiment of the present invention, the material of the stress release layer 70 is preferably selected from at least one of silicon nitride, silicon oxide or silicon oxynitride.

[0054] In the embodiment of the present invention, the thickness of the stress release layer 70 is not limited and can be set accordingly as needed. If the thickness of the stress release layer 70 is too small, it may be easily deformed and cannot effectively release stress; if the thickness of the stress release layer 70 is too large, it may cause the thickness of the flexible display substrate 10 to increase, which is not conducive to the thinness of the flexible display substrate 10, and if the thickness is too large, when the IC is crimped with the flexible display substrate 10, the conductive pattern 40 on the IC cannot be effectively connected to the conductive terminal. Based on this, in the embodiment of the present invention, it is preferred that the thickness of the stress release layer 70 is 0.1 to 1.0 μm, and it is further preferred that the thickness of the stress release layer 70 is 0.5 μm.

[0055] Based on the above, the flexible display substrate provided in the embodiment of the present invention may be a flexible display substrate in a liquid crystal display device, or may be a flexible display substrate in an organic electroluminescent display device.

[0056] When the flexible display substrate is a display substrate in an organic electroluminescent display device, after the display device is formed by evaporation on the flexible base substrate 50 , the display device is further encapsulated by using an encapsulation layer.

[0057] Preferably, the flexible display substrate 10 further includes an encapsulation layer; the stress release layer 70 is made of the same layer and the same material as at least one layer of the encapsulation layer.

[0058] The encapsulation layer may include only one layer, or may include two or more layers. When the encapsulation layer includes multiple layers, the stress release layer 70 may be the same layer and material as any layer in the encapsulation layer, or multiple layers in the stress release layer 70 may be the same layer and material as multiple layers in the encapsulation layer.

[0059] In the embodiment of the present invention, since the stress release layer 70 and at least one of the encapsulation layers are made of the same material, the stress release layer 70 and at least one of the encapsulation layers may be manufactured with partially or entirely the same process, thereby simplifying the manufacturing process of the flexible display substrate 10.

[0060] Further preferably, Figure 6As shown, the encapsulation layer 80 includes a first inorganic layer 801, a second inorganic layer 802 and an organic layer 803 arranged between the first inorganic layer 801 and the second inorganic layer 802; the stress release layer 70 is in the same layer and material as the first inorganic layer 801 or the second inorganic layer 802; or, the stress release layer 70 includes a first sub-stress release layer and a second sub-stress release layer arranged in a stacked manner, the first sub-stress release layer is in the same layer and material as the first inorganic layer 801, and the second sub-stress release layer is in the same layer and material as the second inorganic layer 802.

[0061] Here, the materials of the first inorganic layer 801 and the second inorganic layer 802 are not limited, as long as they are inorganic materials. For example, the materials of the first inorganic layer 801 and the second inorganic layer 802 can be at least one of silicon nitride, silicon oxide, or silicon oxynitride. In addition, the material of the first inorganic layer 801 and the material of the second inorganic layer 802 can be the same or different.

[0062] In the embodiment of the present invention, when the stress release layer 70 and the first inorganic layer 801 in the encapsulation layer 80 are of the same layer and material, the stress release layer 70 and the first inorganic layer 801 can be manufactured with the same process in part or all; when the stress release layer 70 and the second inorganic layer 802 in the encapsulation layer 80 are of the same layer and material, the stress release layer 70 and the second inorganic layer 802 can be manufactured with the same process in part or all; when the first sub-stress release layer and the first inorganic layer 801 are of the same layer and material, and the second sub-stress release layer and the second inorganic layer 802 are of the same layer and material, the first sub-stress release layer and the first inorganic layer 801 can be manufactured with the same process in part or all, and the second sub-stress release layer and the second inorganic layer 802 can be manufactured with the same process in part or all, which simplifies the manufacturing process of the flexible display substrate 10. In addition, since the material of the stress release layer 70 is an inorganic material, the deformation of the flexible display substrate 10 can be effectively suppressed.

[0063] In the embodiment of the present invention, the stress release layer 70 may further include a third sub-stress release layer. The third sub-stress release layer and the organic layer 803 are in the same layer and material. In this way, the third sub-stress release layer and the organic layer 803 may be manufactured with partially or entirely the same process. At this time, the stress release layer 70 includes a first sub-stress release layer, a second sub-stress release layer and a third sub-stress release layer.

[0064] Preferably, Figure 7 As shown, the flexible display substrate 10 further includes a buffer layer 90 and / or a barrier layer 90 disposed between the flexible substrate 50 and the conductive terminal 60. Figure 7 The barrier layer is not shown.

[0065] The materials of the buffer layer 90 and the barrier layer may be, for example, at least one of SiO 2 (silicon dioxide), TiO 2 (titanium dioxide) or CeO 2 (cerium dioxide).

[0066] In the embodiment of the present invention, a buffer layer 90 is provided between the flexible substrate 50 and the conductive terminal 60. Thus, when the flexible display substrate 10 is deformed, the buffer layer 90 can reduce the deformation of the film layer on the buffer layer 90. A barrier layer is provided between the flexible substrate 50 and the conductive terminal 60. The barrier layer can prevent oxygen or water vapor from entering the flexible display substrate 10 and corroding the flexible display substrate 10.

[0067] In the embodiment of the present invention, when the flexible display substrate is a flexible touch display substrate, Figure 8 As shown, the flexible display substrate also includes a flat layer 140 and a touch layer 150 arranged on the flat layer 140; the touch layer 150 includes a first touch electrode layer 1501, a second touch electrode layer 1502, and an insulating layer 1503 arranged between the first touch electrode layer 1501 and the second touch electrode layer 1502; the stress release layer 70 is in the same layer and material as the flat layer 140 or the insulating layer 1503; or, the stress release layer 70 includes a first sub-stress release layer and a second sub-stress release layer that are stacked, the first sub-stress release layer is in the same layer and material as the flat layer 140, and the second sub-stress release layer is in the same layer and material as the insulating layer 1503.

[0068] It should be noted that a plurality of film layers are arranged between the flat layer 140 and the flexible substrate 50. Figure 8 Not shown.

[0069] Here, the material of the planarization layer 140 and the insulating layer 1503 is not limited, and the material of the planarization layer 140 or the insulating layer 1503 may be at least one of silicon nitride, silicon oxide, or silicon oxynitride.

[0070] In addition, the specific structures of the first touch electrode layer 1501 and the second touch electrode layer 1502 may be the same as the touch display substrate in the prior art, and will not be described in detail herein.

[0071] In the embodiment of the present invention, when the stress release layer 70 and the flat layer 140 are of the same layer and the same material, the stress release layer 70 and the flat layer 140 may be manufactured with partially or all of the same process; when the stress release layer 70 and the insulating layer 1503 are of the same layer and the same material, the stress release layer 70 and the insulating layer 1503 may be manufactured with partially or all of the same process; when the stress release layer 70 includes a first sub-stress release layer and a second sub-stress release layer, the first sub-stress release layer and the flat layer 140 are of the same layer and the same material, and the second sub-stress release layer and the insulating layer 1503 are of the same layer and the same material, the first sub-stress release layer and the flat layer 140 may be manufactured with partially or all of the same process, and the second sub-stress release layer and the insulating layer 1503 may be manufactured with partially or all of the same process.

[0072] Further preferably, Fig. 9 As shown, the flexible display substrate 10 also includes a first connection pattern 160 arranged on the side of the conductive terminal 60 away from the flexible base substrate 50, and the first connection pattern 160 is connected to the conductive terminal 60; the first connection pattern 160 is in the same layer and material as the first touch electrode layer 1501 or the second touch electrode layer 1502; or, the first connection pattern 160 includes a first sub-connection pattern and a second sub-connection pattern arranged in a stacked manner, the first sub-connection pattern is in the same layer and material as the first touch electrode layer 1501, and the second sub-connection pattern is in the same layer and material as the second touch electrode layer 1502.

[0073] It should be noted that the first connection pattern 160 is connected to the conductive terminal 60 , and the connection here may be a direct connection, that is, the first connection pattern 160 is in contact with the conductive terminal 60 , or an indirect connection through other film layers.

[0074] Here, a first connection pattern 160 is disposed on the conductive terminal 60 , which is beneficial for exporting the signal on the conductive terminal 60 to the conductive pattern 40 on the IC when the IC is crimped with the flexible display substrate 10 .

[0075] In an embodiment of the present invention, when the first connection pattern 160 and the first touch electrode layer 1501 are in the same layer and made of the same material, the first connection pattern 160 and the first touch electrode layer 1501 may be manufactured using partially or completely the same process; when the first connection pattern 160 and the second touch electrode layer 1502 are in the same layer and made of the same material, the first connection pattern 160 and the second touch electrode layer 1502 may be manufactured using partially or completely the same process; when the first connection pattern 160 includes a first sub-connection pattern and a second sub-connection pattern, the first sub-connection pattern and the first touch electrode layer 1501 are in the same layer and made of the same material, the first sub-connection pattern and the first touch electrode layer 1501 may be manufactured using partially or completely the same process, the second sub-connection pattern and the second touch electrode layer 1502 are in the same layer and made of the same material, the second sub-connection pattern and the second touch electrode layer 1503 may be manufactured using partially or completely the same process.

[0076] Preferably, Fig. 9 and Fig.10 As shown, the flexible display substrate 10 further includes a second connection pattern 100 disposed between the conductive terminal 60 and the stress release layer 70 , and the second connection pattern 100 is connected to the conductive terminal 60 .

[0077] It should be noted that the second connection pattern 100 is connected to the conductive terminal 60 . The connection here may be a direct connection, that is, the second connection pattern 100 is in contact with the conductive terminal 60 , or an indirect connection through other film layers.

[0078] The second connection pattern 100 can be formed simultaneously with the metal wiring of the display area 01 .

[0079] Here, the material of the second connection pattern 100 is not limited, and may be, for example, a metal single substance such as Ag (silver), Cu (copper), Al (aluminum), or a metal oxide.

[0080] In an embodiment of the present invention, a second connection pattern 100 is arranged between the conductive terminal 60 and the stress release layer 70. The second connection pattern 100 is connected to the conductive terminal 60, and the signal on the conductive terminal 60 can be exported to the second connection pattern 100, thereby preventing the signal on the conductive terminal 60 from not being transmitted to the conductive pattern 40 due to poor contact between the conductive terminal 60 and the conductive pattern 40 on the IC when the IC is crimped with the flexible display substrate 10.

[0081] Based on the above, it should be noted that the flexible display substrate 10 provided in the embodiment of the present invention may include only the first connection pattern 160 or the second connection pattern 100, or may include the first connection pattern 160 or the second connection pattern 100. Fig. 9 The illustrated structure includes both the first connection pattern 160 and the second connection pattern 100 .

[0082] Further preferably, the metal trace is a gate line, the conductive terminal 60 is in the same layer and material as the gate line, and the second connection pattern 100 is in the same layer and material as the data line; or, the metal trace is a data line, the conductive terminal 60 is in the same layer and material as the data line, and the second connection pattern 100 is in the same layer and material as the gate line.

[0083] In an embodiment of the present invention, when the conductive terminal 60 and the gate line are in the same layer and material, and the second connection pattern 100 and the data line are in the same layer and material, the conductive terminal 60 can be manufactured simultaneously with the gate line, and the second connection pattern 100 can be manufactured simultaneously with the data line; or, when the conductive terminal 60 and the data line are in the same layer and material, and the second connection pattern 100 and the gate line are in the same layer and material, the conductive terminal 60 can be manufactured simultaneously with the data line, and the second connection pattern 100 can be manufactured simultaneously with the gate line, thereby simplifying the manufacturing process of the flexible display substrate 10.

[0084] Preferably, Fig.11 As shown, the flexible display substrate 10 may further include an intermediate dielectric layer 110 disposed between the conductive terminal 60 and the second connection pattern 100 ; the portion of the intermediate dielectric layer 110 located in the Pad region 04 is hollowed out.

[0085] The material of the intermediate dielectric layer 110 is not limited, and may be, for example, at least one of silicon nitride, silicon oxide, or silicon oxynitride.

[0086] Preferably, in the embodiment of the present invention, the intermediate dielectric layer 110 is made of the same layer and material as the insulating layer disposed between the gate lines and the data lines in the display area 01 , so that the insulating layer and the intermediate dielectric layer 110 can be formed simultaneously, thereby simplifying the manufacturing process of the flexible display substrate 10 .

[0087] An embodiment of the present invention provides a flexible display device, including the above-mentioned flexible display substrate 10 and an IC; the IC includes a conductive pattern 40 ; wherein the conductive pattern 40 of the IC is crimped to the conductive terminal 60 of the flexible display substrate 10 .

[0088] Here, the conductive pattern 40 of the IC is crimped with the conductive terminal 60 of the flexible display substrate 10, and the conductive terminal 60 is connected to the metal trace of the display area, so that the signal on the IC can be input to the metal trace or the signal on the metal trace can be input to the IC.

[0089] Among them, the conductive pattern 40 of the IC passes through the hollow area of ​​the stress release layer 70 in the flexible display substrate 10 and is crimped with the conductive terminal 60. In order to ensure that the conductive pattern 40 can be connected to the conductive terminal 60, the projection of the conductive pattern 40 on the flexible substrate substrate 50 is located within the projection of the boundary of the hollow area of ​​the stress release layer 70 on the flexible substrate substrate 50, or the projection of the boundary of the conductive pattern 40 on the flexible substrate substrate 50 overlaps with the projection of the boundary of the hollow area of ​​the stress release layer 70 on the flexible substrate substrate 50. Further, when the IC is crimped with the flexible display substrate 10, in order to facilitate the connection between the conductive pattern 40 on the IC and the conductive terminal 60, the embodiment of the present invention preferably has the projection of the conductive pattern 40 on the flexible substrate substrate 50 located within the projection of the boundary of the hollow area of ​​the stress release layer 70 on the flexible substrate substrate 50.

[0090] It should be noted that if Fig.12 As shown, after the IC 120 and the flexible display substrate 10 are crimped together in the flexible display device, a flexible printed circuit board 130 (Flexible Printed Circuit, FPC for short) is connected to the IC 120 .

[0091] An embodiment of the present invention provides a flexible display device, wherein a flexible display substrate 10 of the flexible display device includes a plurality of conductive terminals 60 and a stress release layer 70 disposed on the conductive terminals 60. Since a portion of the stress release layer 70 located in the pad area 04 is hollowed out to expose the conductive terminals 60, after the flexible substrate 50 and the protective substrate 20 are bonded together by the adhesive 30, when the IC is crimped with the conductive pattern 40 of the flexible display substrate 10 to connect the conductive pattern 40 on the IC with the conductive terminal 60, although the adhesive 30 under the conductive pattern 40 will flow to the area between the conductive patterns 40, since the stress release layer 70 is disposed on the flexible display substrate 10, the stress release layer 70 can offset the force generated by the adhesive 30 toward the stress release layer 70, so that the stress release layer 70 can release stress and prevent the binding area of ​​the flexible display substrate 10 from warping, thereby avoiding problems such as metal trace breakage caused by deformation of the flexible display substrate 10, poor contact of the metal trace, and short circuit caused by aggregation of conductive particles.

[0092] The embodiment of the present invention further provides a method for preparing a flexible display substrate 10, including a binding area 03, wherein the binding area 03 includes a Pad area 04, such as Fig.13 As shown, the preparation method comprises:

[0093] S100 , forming a plurality of conductive terminals 60 located in the binding area 03 on the flexible substrate 50 .

[0094] The material of the flexible substrate 50 is not limited, and may be PI, for example.

[0095] S101 , forming a stress release layer 70 located in the binding area 03 on the conductive terminal 60 , and hollowing out a portion of the stress release layer 70 located in the Pad area 04 to expose the conductive terminal 60 .

[0096] Here, the material of the stress release layer 70 is not limited, and can be an organic material or an inorganic material. Since the function of the stress release layer 70 is to release stress and inhibit deformation of the flexible display substrate, the material used to prepare the stress release layer 70 should have a relatively high hardness and be not easily deformed.

[0097] An embodiment of the present invention provides a method for preparing a flexible display substrate. The flexible display substrate 10 includes a plurality of conductive terminals 60 and a stress release layer 70 formed on the conductive terminals 60. Since the portion of the stress release layer 70 located in the Pad area 04 is hollowed out to expose the conductive terminals 60, after the flexible base substrate 50 and the protective substrate 20 are bonded by the adhesive 30, when the IC is crimped with the conductive pattern 40 of the flexible display substrate 10 to connect the conductive pattern 40 on the IC with the conductive terminal 60, although the adhesive 30 under the conductive pattern 40 will flow to the area between the conductive patterns 40, since the stress release layer 70 is provided on the flexible display substrate 10, the stress release layer 70 can offset the force generated by the adhesive 30 toward the stress release layer 70, so that the stress release layer 70 can release stress and prevent the binding area of ​​the flexible display substrate 10 from warping, thereby avoiding problems such as metal wiring breakage caused by deformation of the flexible display substrate 10, poor contact of the metal wiring, and short circuit caused by aggregation of conductive particles.

[0098] Preferably, the above-mentioned preparation method further includes: forming a packaging layer 80 on the conductive terminal 60; forming the stress release layer 70 and forming the packaging layer 80, specifically including:

[0099] S200 , forming a first inorganic pattern layer including a first inorganic layer 801 on the conductive terminal 60 .

[0100] The material of the first inorganic pattern layer is not limited, and may be, for example, at least one of silicon nitride, silicon oxide or silicon oxynitride.

[0101] S201 , forming an organic layer 803 on the first inorganic layer 801 .

[0102] Here, the organic layer 803 may be formed by ink-jet printing (IJP for short).

[0103] S202 , forming a second inorganic pattern layer including a second inorganic layer 802 on the organic layer 803 .

[0104] Here, the material of the second inorganic pattern layer is not limited, and for example, it may be at least one of silicon nitride, silicon oxide, or silicon oxynitride.

[0105] Among them, the first inorganic pattern layer also includes: a first sub-stress release layer located in the binding area 03; and / or the second inorganic pattern layer also includes: a second sub-stress release layer located in the binding area 03; the stress release layer 70 includes the first sub-stress release layer and / or the second sub-stress release layer, and the encapsulation layer 80 includes a first inorganic layer 801, an organic layer 803 and a second inorganic layer 802.

[0106] It should be noted that the stress release layer 70 may include only the first sub-stress release layer. Since the stress release layer 70 is located in the hollow portion of the Pad area 04, the first sub-stress release layer is located in the hollow portion of the Pad area 04. It may also include only the second sub-stress release layer. Since the stress release layer 70 is located in the hollow portion of the Pad area 04, the second sub-stress release layer is located in the hollow portion of the Pad area 04. Of course, it may also include the first sub-stress release layer and the second sub-stress release layer. Since the stress release layer 70 is located in the hollow portion of the Pad area 04, the portions of the first sub-stress release layer and the second sub-stress release layer located in the Pad area 04 are both hollow.

[0107] When the first inorganic pattern layer also includes: a first sub-stress release layer located in the binding area 03, there is no limitation on how to form the first inorganic pattern layer. The following provides a specific implementation method, using an open mask plate (OpenMask) for shielding, wherein at least the display area 01 and the binding area 03 are not blocked, and a low-temperature chemical vapor deposition method (Chemical Vapor Deposition, referred to as CVD) is used to deposit inorganic materials. Since the display area 01 and the binding area 03 are not blocked, a first inorganic layer 801 can be formed in the display area 01, and a third inorganic layer can be formed in the binding area 03, and then the third inorganic layer is subjected to a composition process to form a first sub-stress release layer. The composition process here includes coating photoresist, masking, exposure, development and etching processes. When the second inorganic pattern layer also includes: a second sub-stress release layer located in the binding area 03, the formation process of the second inorganic pattern layer is similar to the formation process of the above-mentioned first inorganic pattern layer, and will not be repeated here.

[0108] When the first inorganic pattern layer only includes the first inorganic layer 801, the opening mask plate used at this time at least covers the binding area 03, so that the inorganic material can be deposited in the display area 01 by low-temperature chemical vapor deposition, thereby forming the first inorganic layer 801 in the display area 01. When the second inorganic pattern layer only includes the second inorganic layer 802, the formation process of the second inorganic layer 802 is similar to the formation process of the first inorganic layer 801 when the first inorganic pattern layer only includes the first inorganic layer 801, and will not be repeated here.

[0109] In addition, if a first organic layer is formed in the binding region 03 while the organic layer 803 is formed, the stress release layer 70 further includes the first organic layer.

[0110] In the embodiment of the present invention, since the first stress release sub-layer and the first inorganic layer 801 can be manufactured using partially the same process, and / or the second stress release sub-layer and the second inorganic layer 802 can be manufactured using partially the same process, the manufacturing process of the flexible display substrate 10 is simplified.

[0111] Preferably, the above preparation method further comprises: forming a packaging layer 80 on the conductive terminal 60, forming a stress release layer 70 and forming the packaging layer 80, specifically comprising:

[0112] S300 , forming a first inorganic pattern layer including a first inorganic layer 801 on the conductive terminal 60 .

[0113] S301 , forming an organic layer 803 on the first inorganic layer 801 .

[0114] S302 , forming a second inorganic pattern layer including a second inorganic layer 802 on the organic layer 803 .

[0115] S303, the first inorganic pattern layer further includes: a third inorganic layer located in the binding area 03, and the third inorganic layer is patterned to form a first sub-stress release layer; and / or, the second inorganic pattern layer further includes: a fourth inorganic layer located in the binding area 03, and the fourth inorganic layer is patterned to form a second sub-stress release layer. Wherein, the stress release layer 70 includes the first sub-stress release layer and / or the second sub-stress release layer; the encapsulation layer 80 includes the first inorganic layer 801, the organic layer 803, and the second inorganic layer 802.

[0116] When the first inorganic pattern layer also includes a third inorganic layer located in the binding area 03, there is no limitation on how to form the first inorganic pattern layer. A specific implementation method is provided below, in which an open mask is used for shielding, wherein at least the display area 01 and the binding area 03 are not shielded, and inorganic materials are deposited by low-temperature chemical vapor deposition. Since the display area 01 and the binding area 03 are not shielded, the first inorganic layer 801 can be formed in the display area 01, and the third inorganic layer can be formed in the binding area 03. When the second inorganic pattern layer also includes: a fourth inorganic layer located in the binding area 03, the formation process of the second inorganic pattern layer is similar to the formation process of the first inorganic pattern layer, and will not be repeated here.

[0117] Here, after the encapsulation layer 80 of the display area 01 is manufactured, the third inorganic layer is patterned to form a first sub-stress release layer, and / or the fourth inorganic layer is patterned to form a second sub-stress release layer.

[0118] Among them, the stress release layer 70 may include only the first sub-stress release layer. Since the stress release layer 70 is located in the hollow portion of the Pad area 04, the first sub-stress release layer is located in the hollow portion of the Pad area; it may also include only the second sub-stress release layer. Since the stress release layer 70 is located in the hollow portion of the Pad area 04, the second sub-stress release layer is located in the hollow portion of the Pad area; of course, it may also include the first sub-stress release layer and the second sub-stress release layer. Since the stress release layer 70 is located in the hollow portion of the Pad area 04, the portions of the first sub-stress release layer and the second sub-stress release layer located in the Pad area 04 are both hollow.

[0119] On this basis, it should be noted that when the stress release layer 70 includes a first sub-stress release layer and a second sub-stress release layer, the third inorganic layer and the fourth inorganic layer can be simultaneously patterned to form the first sub-stress release layer and the second sub-stress release layer, or the third inorganic layer can be first patterned to form the first sub-stress release layer, and then the fourth inorganic layer can be patterned to form the second sub-stress release layer.

[0120] In addition, if a first organic layer is formed in the binding region 03 while the organic layer 803 is formed, the stress release layer 70 further includes the first organic layer.

[0121] In the embodiment of the present invention, since the first stress release sub-layer and the first inorganic layer 801 can be manufactured using partially the same process, and / or the second stress release sub-layer and the second inorganic layer 802 can be manufactured using partially the same process, the manufacturing process of the flexible display substrate 10 is simplified.

[0122] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A flexible display substrate, comprising a binding area, wherein the binding area comprises a connection area, characterized in that: The binding area of ​​the flexible display substrate comprises: a plurality of conductive terminals and a stress release layer sequentially arranged on a flexible substrate; Part of the stress release layer located in the connection area is hollowed out to expose the conductive terminal; and the conductive terminal is connected to the metal wiring in the display area.

2. The flexible display substrate according to claim 1, characterized in that: The material of the stress release layer includes inorganic material.

3. The flexible display substrate according to claim 2, characterized in that: The material of the stress release layer is selected from at least one of silicon nitride, silicon oxide or silicon oxynitride.

4. The flexible display substrate according to claim 1, characterized in that: The thickness of the stress release layer is 0.1-1.0 μm.

5. The flexible display substrate according to claim 1, characterized in that: The flexible display substrate further includes an encapsulation layer; the stress release layer and at least one layer of the encapsulation layer are in the same layer and made of the same material.

6. The flexible display substrate according to claim 5, characterized in that: The encapsulation layer includes a first inorganic layer, a second inorganic layer, and an organic layer disposed between the first inorganic layer and the second inorganic layer; The stress release layer is in the same layer and made of the same material as the first inorganic layer or the second inorganic layer; Alternatively, the stress release layer includes a first sub-stress release layer and a second sub-stress release layer which are stacked, the first sub-stress release layer and the first inorganic layer are in the same layer and made of the same material, and the second sub-stress release layer and the second inorganic layer are in the same layer and made of the same material.

7. The flexible display substrate according to claim 1, characterized in that: The flexible display substrate further includes a flat layer and a touch layer disposed on the flat layer; the touch layer includes a first touch electrode layer, a second touch electrode layer, and an insulating layer disposed between the first touch electrode layer and the second touch electrode layer; The stress release layer is made of the same layer and material as the flat layer or the insulating layer; Alternatively, the stress release layer includes a first sub-stress release layer and a second sub-stress release layer which are stacked, the first sub-stress release layer and the flat layer are in the same layer and made of the same material, and the second sub-stress release layer and the insulating layer are in the same layer and made of the same material.

8. The flexible display substrate according to claim 7, characterized in that: The flexible display substrate further comprises a first connection pattern arranged on a side of the conductive terminal away from the flexible base substrate, the first connection pattern being connected to the conductive terminal; The first connection pattern is in the same layer and made of the same material as the first touch electrode layer or the second touch electrode layer; Alternatively, the first connection pattern includes a first sub-connection pattern and a second sub-connection pattern which are stacked, the first sub-connection pattern and the first touch electrode layer are in the same layer and material, and the second sub-connection pattern and the second touch electrode layer are in the same layer and material.

9. The flexible display substrate according to claim 1, characterized in that: The flexible display substrate further includes a second connection pattern disposed between the conductive terminal and the stress release layer, wherein the second connection pattern is connected to the conductive terminal.

10. The flexible display substrate according to claim 9, characterized in that: The metal wiring is a gate line, the conductive terminal and the gate line are in the same layer and material, and the second connection pattern and the data line are in the same layer and material; Alternatively, the metal wiring is a data line, the conductive terminal and the data line are made of the same layer and material, and the second connection pattern and the gate line are made of the same layer and material.

11. A flexible display device, characterized in that: A flexible display substrate and an IC as claimed in any one of claims 1 to 10; wherein the IC comprises a conductive pattern; Wherein, the conductive pattern of the IC is crimped to the conductive terminal of the flexible display substrate.

12. The flexible display device according to claim 11, characterized in that: The projection of the conductive pattern on the flexible substrate is located within the projection of the boundary of the hollow region of the stress release layer on the flexible substrate.

13. A method for preparing a flexible display substrate, comprising a binding area, wherein the binding area comprises a connection area, characterized in that: include: forming a plurality of conductive terminals located in the binding area on the flexible substrate; A stress release layer is formed on the conductive terminal and located in the binding area, and a portion of the stress release layer located in the connection area is hollowed out to expose the conductive terminal.

14. The preparation method according to claim 13, characterized in that: The preparation method further comprises: forming a packaging layer on the conductive terminal; Forming the stress release layer and forming the encapsulation layer specifically includes: forming a first inorganic pattern layer including a first inorganic layer on the conductive terminal; forming an organic layer on the first inorganic layer; forming a second inorganic pattern layer including a second inorganic layer on the organic layer; Among them, the first inorganic pattern layer also includes: a first sub-stress release layer located in the binding area; and / or the second inorganic pattern layer also includes: a second sub-stress release layer located in the binding area; the stress release layer includes the first sub-stress release layer and / or the second sub-stress release layer, and the encapsulation layer includes the first inorganic layer, the organic layer and the second inorganic layer.

15. The preparation method according to claim 13, characterized in that: The preparation method further comprises: forming a packaging layer on the conductive terminal; Forming the stress release layer and forming the encapsulation layer specifically includes: forming a first inorganic pattern layer including a first inorganic layer on the conductive terminal; forming an organic layer on the first inorganic layer; forming a second inorganic pattern layer including a second inorganic layer on the organic layer; The first inorganic pattern layer further includes: a third inorganic layer located in the binding area, and the third inorganic layer is patterned to form a first sub-stress release layer; and / or the second inorganic pattern layer further includes: a fourth inorganic layer located in the binding area, and the fourth inorganic layer is patterned to form a second sub-stress release layer; Wherein, the stress release layer includes the first sub-stress release layer and / or the second sub-stress release layer; and the encapsulation layer includes the first inorganic layer, the organic layer and the second inorganic layer.

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