The application claims priority to the Chinese patent application No. 201710114786.3, filed on Feb. 28, 2017 with SIPO and entitled “Flexible Display Panel, Manufacturing Method thereof and Display Device”, which is incorporated herein by reference in its entirety.
Embodiments of the present disclosure relate to a flexible display panel, a manufacturing method thereof and a display device.
Flexible devices are more and more widely applied in our lives. Flexible electronic devices, especially flexible display panels, have attracted more and more attention due to characteristics, such as lightness, thinness, flexibility, foldability and good mechanical properties. However, when being bent, as the flexible display panel adopts a large number of inorganic processes, the total thickness of the inorganic film layer is generally more than 1,000 nm. For example, it is more likely that cracks and even fractures occur in the inorganic film layer, such as SiNx, due to the impact of positive and negative stress when the inorganic film layer is bent frequently, resulting in a compromised quality and even damage and failure of the flexible display panel.
Embodiments of the present disclosure provide a flexible display panel, a manufacturing method thereof and a display device.
Embodiments of the present disclosure provide a flexible display panel, comprising: a flexible substrate; and inorganic insulating layer(s) and an organic insulating layer provided on the flexible substrate. The inorganic insulating layer(s) is/are provided with a recess in a region to be bent of the flexible display panel; and the organic insulating layer at least covers a surface of the recess.
Embodiments of the present disclosure provide a display device, comprising any of the flexible display panel.
Embodiments of the present disclosure provide a method of manufacturing any of the flexible display panel, comprising: forming the inorganic insulating layer(s) and the organic insulating layer on the flexible substrate; and forming the recess in the inorganic insulating layer(s) in the region to be bent of the flexible display panel, and allowing the organic insulating layer to at least cover a surface of the recess.
Embodiments of the present disclosure will be described in more detail below with reference to accompanying drawings to allow an ordinary skill in the art to more clearly understand embodiments of the present disclosure, in which:
Technical solutions of the embodiments will be described in a clearly and fully understandable way in connection with the drawings related to the embodiments of the disclosure. It is apparent that the described embodiments are just a part but not all of the embodiments of the disclosure. Based on the described embodiments herein, those skilled in the art can obtain other embodiment(s), without any creative work, which shall be within the scope of the disclosure.
Unless otherwise defined, all the technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which the present disclosure belongs. The terms, such as “first,” “second,” or the like, which are used in the description and the claims of the present disclosure, are not intended to indicate any sequence, amount or importance, but for distinguishing various components. The terms, such as “comprise/comprising,” “include/including,” or the like are intended to specify that the elements or the objects stated before these terms encompass the elements or the objects and equivalents thereof listed after these terms, but not preclude other elements or objects. The terms, “on,” “under,” or the like are only used to indicate relative position relationship, and when the position of the object which is described is changed, the relative position relationship may be changed accordingly.
The thickness of layers, the shape of regions, the features, the shape and the size of structures or the like in the accompanying drawings do not reflect a true scale and are only used for schematically illustrating the content of the present disclosure.
Embodiments of the present disclosure provide a flexible display panel. In a flexible display panel provided with a region to be bent frequently, a recess is formed in the region to be bent frequently of inorganic insulating layer(s); an organic insulating layer of which the flexibility is greater than that of the inorganic insulating layer(s) is arranged between the inorganic insulating layer(s) and a source-drain layer; and the organic insulating layer is allowed to at least cover or completely cover the recess in the region to be bent frequently. In this way, for those display panels which can be bent, they can adopt the structure(s) of the embodiments of the present disclosure.
As shown in
For instance, the flexible display panel comprises a flexible substrate 101, inorganic insulating layer(s) 102 disposed on the flexible substrate 101, and a recess 100 formed in a region to be bent b. The flexible display panel may also comprise an organic insulating layer 103 and a source-drain layer 104. For instance, the organic insulating layer 103 at least completely covers a surface of the recess 100, and the flexibility of the organic insulating layer 103 is greater than that of the inorganic insulating layer(s) 102.
The flexible substrate, for instance, may be a plastic substrate.
For instance, inorganic insulating layers 102, an organic insulating layer 103 and a source-drain layer 104 are disposed on a flexible substrate 101. The region to be bent b may be disposed in a non-display region of the flexible display panel and may be disposed in the display region. For instance, the region to be bent b is disposed in a corresponding region on the inorganic insulating layers not provided with through holes 108, namely a region except through-hole region d. The flexible display panel comprises the inorganic insulating layers 102, the organic insulating layer 103 and the source-drain layer 104, and it may also comprise other functional layers 1024 (not specifically shown for clarity), as shown in
As cracks and even fractures easily occur in inorganic insulating layer(s) of the flexible display panel due to frequently bending, in the flexible display panel provided by the embodiment of the present disclosure, the recess is formed in the region to be bent of the inorganic insulating layer(s); the organic insulating layer of which the flexibility is greater than that of the inorganic insulating layer(s) is additionally arranged; and the organic insulating layer is allowed to at least cover or completely cover the recess in the region to be bent. In this way, the inorganic layer(s) in the region to be bent is reduced, so as to prevent cracks and even fractures occurring in the inorganic layer(s) in the region to be bent due to frequently bending, avoid the damage of the stress to a device when it is bent, and improve the reliability and the service life of the device.
For instance, the organic insulating layer formed in the embodiment of the present disclosure may, as shown in
For the convenience of production, processes are not added. As shown in
In the embodiment of the present disclosure, the organic insulating layer with strong flexibility under a given bending radius is additionally arranged between the inorganic insulating layer(s) and the source-drain layer. The flexibility under the given bending radius refers to the ability of the material to resist stress without damage when the material is bent to a certain bending radius (generally small bending radius, detailed description will be given below). When the flexibility of the material under the given bending radius is higher, the material is less likely to create cracks and even fractures when being bent.
The structure in the embodiment of the present disclosure is mainly applied in the flexible display panel provided with fixed regions to be bent. The region to be bent is generally disposed in the non-pixel region. In order to prevent cracks and even fractures occurring in the inorganic insulating layer(s) in the region to be bent due to frequently bending, in the embodiment of the present disclosure, the recess is formed in the region to be bent of the inorganic insulating layer, and the organic insulating layer at least completely covers the surface of the recess.
For instance, the region to be bent on the flexible display panel may generally be divided into a main bending region and the remaining bending region. The main bending region refers to a region with small bending radius, e.g., with the bending radius of less than about 5 mm. The remaining bending region refers to a region with slight bending and large bending radius, e.g., with the bending radius of about 20 mm.
The bending radius of the region to be bent may be varied according to the design demands of products. As cracks and even fractures easily occur in the inorganic insulating layer(s) in the region with larger bending radius, the bending region in the embodiment of the present disclosure normally refers to the bending region with small bending radius, namely the main bending region, for instance, the bending region which has a given bending radius of less than 5 mm.
For instance, the flexible display panel provided by the embodiment of the present disclosure may also be a flexible display panel of other bending types besides the fixed region to be bent, e.g., a flexible display panel in which the entire display panel may be bent along a certain direction, and even may be a flexible display panel which can be randomly bent. In order to allow the organic insulating layer in the recess to have maximum protection function, the arrangement modes of the recess are also different for display panels of different bending types. For instance, for the flexible display panel comprises a fixed region to be bent, the lengthwise direction of the recess is set along the bending axial direction; for the flexible display panel which can be randomly bent, a circle of recess structure may be arranged around one or more luminous pixel regions and in a non-pixel region which does not emit light; or other structures may be designed, which shall not affect the normal display of the flexible display panel.
For instance, in the flexible display panel provided by an embodiment of the present disclosure, the organic insulating layer may also be filled a space between the inorganic insulating layer(s) and the source-drain layer in addition to completely covering the surface of the recess, and has a function of raising the formed spatial structure. For instance, the organic insulating layer is also filled a space between the source-drain layer and the inorganic insulating layer which is the closest to the source-drain layer.
As shown in
For instance, as the organic insulating layer completely covers the inorganic insulating layer on the upmost layer, the organic insulating layer may have a function of raising the formed spatial structure with a certain thickness. Meanwhile, the organic insulating layer may replace partial inorganic insulating layer(s) by utilization of the insulating function of the organic insulating layer, and the thickness of the inorganic insulating layer on the upmost layer may be properly decreased in the preparing process. In addition, as the flexibility of the organic insulating layer under the given bending radius is greater than that of the inorganic insulating layer(s) under the given bending radius, the thickness of the inorganic insulating layer on the upmost layer is properly decreased, and the organic insulating layer is adopted to replace partial inorganic insulating layer(s), so the probability that cracks and even fractures occur in the inorganic insulating layer(s) due to frequent bending can be reduced, and the damage of the stress to the device when the device is bent can be reduced.
For instance, the material of the organic insulating layer is one or a combination of the following materials, such as polyimide type organic layer. In addition, other insulating layers with good flexibility may also be selected as the organic insulating layer, as long as the flexibility is greater than that of the inorganic insulating layer(s) under the given bending radius.
To further improve the flexibility of the organic insulating layer, material(s) with higher flexibility may be doped into the material of the organic insulating layer. For instance, flexible material is doped into the organic insulating layer. For instance, polyimide material(s) doped with grapheme, or polyimide material(s) doped with nano-ceramic(s) may be adopted to prepare the organic insulating layer.
In addition to the material(s) with higher flexibility may be directly doped into the formed organic insulating layer, a layer of material(s) with higher flexibility may be formed before the operation of forming the organic insulating layer. For instance, as shown in
The flexibility of the material of the additional film layer 105 is greater than that of the material of the organic insulating layer 103. For instance, an orthographic projection of the additional film layer 105 on the flexible substrate 101 falls within the orthographic projection of the organic insulating layer 103 on the flexible substrate 101.
Without affecting the display function, the additional film layer 105 may be disposed in the entire region under the organic insulating layer 103 and may also be only disposed in a region under the organic insulating layer 103 except the recess, or may be only disposed in a region under the organic insulating layer 103 in the recess region. The orthographic projection of the additional film layer on the flexible substrate 101 also correspondingly falls within an orthographic projection of a corresponding part of the organic insulating layer 103 on the flexible substrate 101.
The organic insulating layer 103 may also be formed on the inorganic layer at first and then the additional film layer 105 may be formed on the organic insulating layer 103, as shown in
In the process of forming the additional film layer, material with strong flexibility may be selected. For instance, the material of the additional film layer is one or a combination of the following materials: material which is the same as the material of the organic insulating layer and doped with graphene, material which is the same as the material of the organic insulating layer and doped with nano-ceramic, or graphene.
For instance, the thickness of the organic insulating layer filled between the inorganic insulating layer(s) and the source-drain layer is 0.5 μm-2 μm; and the thickness of the organic insulating layer covering the surface of the recess is 0.5 μm-3 μm.
For instance, in the structure as shown in
Description will be given in the following embodiments by taking the arrangement mode of the organic insulating layer in
For instance, as shown in
For instance, when the region to be bent b is arranged in the non-display region on the border of the flexible display panel, namely when the recess 100 on the inorganic insulating layer(s) 102 or the flexible substrate 101 is disposed in the non-display region, as the leads 1042 of the source/drain electrodes will generally run through the region to be bent, an organic insulating layer with strong flexibility under the given bending radius is added between the inorganic layer on the upmost layer and the source-drain layer, so as to prevent cracks and even fractures occurring in the source/drain leads due to frequent bending.
In addition, in the flexible display panel provided by an embodiment of the present disclosure, when the region to be bent is disposed in the non-display region on the border of the flexible display panel, the number of the main bending regions with the bending radius of not greater than 5 mm is generally 1 or 2, and each region to be bent is provided with a recess structure correspondingly.
When the region to be bent is disposed in the display region, the region shall be kept away from a luminous region as much as possible for the convenience of production.
For instance, the inorganic insulating layer(s) in the embodiment of the present disclosure may include a plurality of layers. For instance, as shown in
For instance, as shown in
For instance, the recess disposed in the region to be bent in the inorganic insulating layer(s) may be, as shown in
For instance, the inorganic insulating layer(s) in the region to be bent may also be completely removed, namely being removed to the upper part of the flexible substrate.
For instance, for the recess 100 disposed in the region to be bent in the inorganic insulating layer(s), the width of the recess opening generally depends on the bending radius. For instance, the width of the recess is 0.5 mm-5 mm. Moreover, for instance, the width of the recess is about 0.5 mm.
For instance, the flexible display panel provided by the embodiments of the present disclosure may be rectangular or may be other abnormal shapes of display panels required to be bent. In addition,
Based on the same concept, the embodiment of the present disclosure also provides a display device, which comprises any foregoing flexible display panel provided by the embodiments of the present disclosure. As the principles of the display device in solving problems are similar to those of the flexible display panel provided by the embodiments of the present disclosure, implementation of the display device may refer to the implementation of the flexible display panel. No repeated description will be given herein.
Based on the same concept, the embodiment of the present disclosure also provides a method for manufacturing a flexible display panel, which is used for manufacturing the flexible display panel provided by the embodiments of the present disclosure. As shown in
S701: sequentially forming inorganic insulating layers on a flexible substrate;
S702: forming a recess in a region to be bent of the inorganic insulating layer(s), forming an organic insulating layer on the inorganic insulating layer(s), and allowing the organic insulating layer to at least completely cover the surface of the recess; and
S703: forming a pattern of a source-drain layer on the organic insulating layer.
The flexibility of the organic insulating layer under a given bending radius is greater than that of the inorganic insulating layer(s) under the given bending radius.
Description will be given below to the example processes of forming the recess and the organic insulating layer.
Process of Forming the Recess and the Organic Insulating Layer by Photolithography
For instance, as shown in
S801: forming the recess by removing partial inorganic insulating layer(s) in the region to be bent of the flexible display panel by photolithography;
S802: forming the organic insulating layer on the inorganic insulating layer(s), and allowing the organic insulating layer to at least completely cover the surface of the recess; and
S803: etching the pixel region in the flexible display panel, forming through holes for preparing the source-drain electrodes, and forming patterns of the inorganic insulating layer(s) and the organic insulating layer.
Detailed description will be given below to the operations of forming the recess and the organic insulating layer by photolithography by taking the case of forming the flexible display panel with the structure in
For instance, in the process of implementing the operation S801, as shown in
For instance, in the process of implementing the operation S802, as shown in
For instance, in the process of implementing the operation S803, as shown in
The structures formed in the process of manufacturing the flexible display panel as shown in
Process of Forming the Recess and the Organic Insulating Layer by a Half-tone Mask Process
As shown in
S1001: forming the organic insulating layer on the inorganic insulating layer(s);
S1002: removing partial organic insulating layer in a preset region and removing the entire organic insulating layer in the region to be bent by a half-tone mask process, in which the preset region is used for forming the through holes of the source-drain electrodes on the inorganic insulating layer(s);
S1003: etching the inorganic insulating layer(s) in the region to be bent to a certain depth by a dry-etching process by adoption of the remaining organic insulating layer as a mask;
S1004: removing the entire organic insulating layer in the preset region by an ashing process, and forming a pattern of the organic insulating layer;
S1005: forming a pattern of the through holes by etching the preset region through an etching process with the pattern of the organic insulating layer as a mask, forming the recess by etching the region to be bent and removing partial inorganic insulating layer(s), and forming a pattern of the inorganic insulating layer(s); and
S1006: forming the organic insulating layer on the inorganic insulating layer(s) by inkjet printing, allowing the organic insulating layer to at least completely cover the surface of the recess, and forming the pattern of the organic insulating layer.
Detailed description will be given below to the operations of forming the recess and the organic insulating layer via a half-tone mask process by taking the case of forming the flexible display panel with the structure in
For instance, in the process of implementing the operation S1001, after the operation of forming the inorganic insulating layer(s), the through holes are not etched, instead, the organic insulating layer is formed on the inorganic insulating layer(s) at first to form the structure as shown in
For instance, in the process of executing the operation S1002, the organic insulating layer on the upmost layer is etched by a half-tone mask process, and the entire organic insulating layer in the region to be bent b is removed when the upper part of the organic insulating layer in a preset region e is removed. The position of the preset region e is used for forming the through holes 108 of the source-drain electrode on the inorganic insulating layer(s), so as to form the structure as shown in
For instance, in the process of implementing the operation S1003, after the operation S1002 is executed, the inorganic insulating layer(s) in the region to be bent is continuously etched to a certain depth by a dry-etching process or other proper processes via the shielding of the remaining organic insulating layer. The recess structure is not etched completely at this operation, instead, it is completely etched in the operation S1005 to form the structure as shown in
For instance, in the process of executing the operation S1004, after the operation S1003, the remaining organic insulating layer in the preset region e is completely removed by an ashing process, and at this point, the pattern of the organic insulating layer is formed, namely forming the structure as shown in
For instance, in the process of implementing the operation S1005, when the complete pattern of the through holes is formed by etching the preset regions e by an etching process via the shielding of the pattern of the organic insulating layer, the region to be bent is continuously etched, and partial inorganic insulating layer(s) is removed to form the pattern of the recess. In this way, the pattern of the inorganic insulating layer(s) is formed, and the structure as shown in
For instance, in the process of implementing the operation S1006, the organic insulating layer may be mainly formed in the recess region on the inorganic insulating layer(s) by inkjet printing and is allowed to at least completely cover the surface of the recess, and the pattern of the organic insulating layer is formed, that is, the structure as shown in
In the two processes of forming the recess and the organic insulating layer, the organic insulating layer can be directly formed, a further improvement may also be made on this basis. For instance, material(s) with stronger flexibility is/are doped into the organic insulating material, or an additional layer 105 with stronger flexibility is formed before or after the operation of forming the organic insulating layer.
For instance, the operation of forming the organic insulating layer on the inorganic insulating layer(s) includes: forming the organic insulating layer doped with flexible material(s) on the inorganic insulating layer(s). For instance, a mixed solution which is uniformly mixed may be prepared in advance, and the mixed solution is an organic insulating material doped with the flexible material(s); the mixed solution is coated on the inorganic insulating layer(s); and finally the organic insulating layer doped with the flexible material(s) is formed. But the uniformity of the doped material(s) must be guaranteed in the manufacturing process, and the formed organic insulating layer may still be formed by the above two processes of forming the recess and the organic insulating layer, without affecting normal functions of other layers.
For instance, the operation of forming the organic insulating layer on the inorganic insulating layer(s) includes: forming an additional film layer on the inorganic insulating layer(s), and forming the organic insulating layer on the additional film layer. Optionally, the forming sequences of the additional film layer and the organic insulating layer may be opposite, namely forming the structure as shown in
The manufacturing process of other flexible display panel structures as shown in
In the method for manufacturing the flexible display panel, provided by the embodiment of the present disclosure, in the process of forming the recess and the organic insulating layer by photolithography, the inorganic insulating layer(s) in the region to be bent is removed by using a mask, and subsequently, the organic insulating layer is coated on the interlayer insulating layer and the through holes of the source-drain electrodes in the display region are etched by using the organic insulating layer as a mask. In the process of forming the recess and the organic insulating layer by a half-tone mask process, the through holes of the source-drain electrodes in the display region may be etched when the inorganic insulating layer(s) in the region to be bent is etched by a half-tone mask process and an ashing process after the operation of forming the entire organic insulating layer, and subsequently, the organic insulating layer which at least completely covers the surface of the recess is formed in the recess in the region to be bent.
In the flexible display panel provided by the embodiments of the present disclosure, the recess is disposed in the region to be bent of the inorganic insulating layer(s); the organic insulating layer, of which the flexibility under the given bending radius is greater than that of the inorganic insulating layer(s), is added; the organic insulating layer is allowed to at least cover or completely cover the recess in the region to be bent; and the inorganic layer(s) in the region to be bent is reduced. In this way, cracks and even fractures are prevented from occurring in the inorganic layer(s) in the region to be bent due to frequent bending, which can avoid the damage of the stress to the device when the device is bent, and improve the reliability and the service life of the device. In addition, as the organic insulating layer may also completely cover the inorganic insulating layer on the upmost layer (e.g., the interlayer insulating layer), the organic insulating layer may replace the function of partial inorganic insulating layer(s) by utilization of the insulating function thereof. In this way, the thickness of the inorganic insulating layer on the upmost layer can be properly reduced in the manufacturing process.
The following points should be noted:
(1) The accompanying drawings in the embodiments of the present disclosure only involve structures relevant to the embodiments of the present disclosure, and other structures may refer to a common design.
(2) For clarity, in the accompanying drawings of the embodiments of the present disclosure, the thickness of layers or regions is enlarged or reduced. That is, the accompanying drawings are not drawn according to actual scales.
(3) Without conflict, the embodiments of the present disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.
The described above are only exemplary embodiments of the present disclosure, and the present disclosure is not intended to be limited thereto. For one of ordinary skill in the art, various changes and alternations may be readily contemplated without departing from the technical scope of the present disclosure, and all of these changes and alternations shall fall within the scope of the present disclosure.
Number | Date | Country | Kind |
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201710114786.3 | Feb 2017 | CN | national |
Filing Document | Filing Date | Country | Kind |
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PCT/CN2017/106060 | 10/13/2017 | WO | 00 |