A display panel, a display device and a preparation method thereof

Abstract

Embodiments of the present application disclose a display panel, a display device and a preparation method thereof. In a specific embodiment, the display panel comprises a substrate, a driving circuit layer, a planarization layer and a pixel definition layer which are sequentially arranged on the substrate; the pixel definition layer comprises a first definition part and a plurality of second definition parts; the first definition part comprises a plurality of first parts extending along a first direction; the second definition parts extend along a second direction; the first direction intersects with the second direction; the first definition part is closer to the substrate than the second definition part; the first definition part has a liquid affinity; at least part of the second definition part has a liquid repellency, and at least part of the second definition part comprises an end part away from the substrate; the second definition part has a second thickness which is substantially uniform; the first definition part has a first thickness; and the second thickness is greater than the first thickness. The embodiment can improve the problem that OLED organic material ink is prone to overflow in the overlapping area of the first definition part and the second definition part.

Description

Technical Field

[0001] This invention relates to the field of display technology, and more specifically, to a display panel, a display device, and a method for manufacturing the same. Background Technology

[0002] Currently, inkjet printing is one way to create the light-emitting layer of OLED (Organic Light Emitting Diode) display devices. It uses a solvent to melt the OLED organic material and then directly prints the melted OLED organic material onto the surface of the display back panel to form the light-emitting layer.

[0003] However, uneven solute deposition is a common problem during inkjet printing and drying. To address this, existing technologies provide a display panel with a pixel-defining layer comprising rows of interconnected regions to improve ink uniformity along its long axis. However, this type of display panel suffers from ink overflow issues. Summary of the Invention

[0004] The purpose of this invention is to provide a display panel, a display device, and a method for manufacturing the same, so as to solve at least one of the problems existing in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A first aspect of the present invention provides a display panel, comprising: a substrate, and a driving circuit layer, a planarization layer, and a pixel defining layer sequentially stacked on the substrate; the pixel defining layer includes a first defining portion and a plurality of second defining portions, the first defining portion including a plurality of first portions extending along a first direction, the second defining portions extending along a second direction, the first direction intersecting the second direction; the first defining portion being closer to the substrate than the second defining portions; the first defining portion being hydrophilic, at least a portion of the second defining portions being hydrophobic, the at least a portion including an end away from the substrate; the second defining portion having a substantially uniform second thickness, the thickness of the first defining portion being a first thickness, and the second thickness being greater than the first thickness.

[0007] The display panel provided by the first aspect of the present invention improves the uniformity of OLED organic material ink in the second direction by providing a second defining portion with a substantially uniform second thickness, and solves the problem that OLED organic material ink is prone to overflow in the overlapping area of ​​the first defining portion and the second defining portion.

[0008] Optionally, the first defining portion further includes a plurality of second portions extending along a second direction, wherein the projection of each second portion on the substrate overlaps the projection of a second defining portion on the substrate.

[0009] This alternative approach easily achieves a second defining portion with a substantially uniform second thickness, and the process is simple and easy to mass-produce.

[0010] Optionally, the projection of each of the second portions onto the substrate coincides with the projection of a second defining portion onto the substrate.

[0011] Optionally, the planarization layer is provided with a plurality of arrayed grooves, and the first part includes a plurality of discontinuously arranged first sub-parts disposed in the grooves.

[0012] This alternative approach can further improve the uniformity of the OLED organic material ink in the second direction, and it is easy to achieve a second thickness with a generally uniform second boundary. The process is simple and easy to mass-produce.

[0013] Optionally, the depth of the first groove is approximately equal to the first thickness.

[0014] Optionally, the first thickness is 0.6μm-1μm, and the second thickness is 1.2μm-1.5μm.

[0015] Optionally, the display panel further includes a plurality of sub-pixels arranged in an array. The sub-pixels are disposed in the opening defined by the first portion and the second defining portion. The sub-pixels include a first sub-pixel, a second sub-pixel, and a third sub-pixel. The first sub-pixel forms a first sub-pixel row along a second direction, the second sub-pixel forms a second sub-pixel row along a second direction, and the third sub-pixel forms a third sub-pixel row along a second direction.

[0016] A second aspect of the present invention provides a display device including a display panel as described in the first aspect of the present invention.

[0017] A third aspect of the present invention provides a method for manufacturing a display panel, comprising:

[0018] Provide substrate;

[0019] A driving circuit layer is sequentially formed on the substrate;

[0020] A planarization layer is formed on the driving circuit layer; and

[0021] A pixel defining layer is formed on the planarization layer; wherein the pixel defining layer includes a first defining portion and a plurality of second defining portions, the first defining portion including a plurality of first portions extending along a first direction, the second defining portions extending along a second direction, the first direction intersecting the second direction; the first defining portion is closer to the substrate than the second defining portion; the first defining portion is hydrophilic, at least a portion of the second defining portion is hydrophobic, the at least a portion including an end away from the substrate; the second defining portion has a uniform second thickness, the thickness of the first defining portion is a first thickness, and the second thickness is greater than the first thickness.

[0022] Optionally, forming a pixel-defining layer on the planarization layer includes:

[0023] A plurality of first portions extending along a first direction and a plurality of second portions extending along a second direction are formed on the planarization layer, forming a first defining portion;

[0024] A plurality of second defining portions extending in the second direction are formed on the plurality of second portions extending in the second direction.

[0025] Optionally, forming a pixel-defining layer on the planarization layer includes:

[0026] Multiple grooves are arranged in an array on the planarization layer, and the depth of the grooves is approximately equal to the first thickness.

[0027] A pixel defining layer adhesive material using a bonding-type hydrophobic material is coated on the planarization layer, and the thickness of the pixel defining layer adhesive material corresponding to the non-groove portion of the planarization layer is the second thickness;

[0028] Using a mask having an opening or blocking portion extending in a second direction, photolithography is performed on the pixel defining layer adhesive material to a second thickness to form the first portion and the second defining portion, wherein the first portion includes a plurality of discontinuously arranged first sub-parts disposed in the groove.

[0029] This alternative method allows the first and second defining portions of the pixel defining layer to be formed simultaneously in a single photolithography process, simplifying the process and improving production efficiency.

[0030] The beneficial effects of this invention are as follows:

[0031] This invention addresses the existing problems by providing a display panel, a display device, and a method for manufacturing the same. By setting the second defining portion to have a substantially uniform second thickness, the uniformity of the OLED organic material ink in the second direction is improved, while the problem of overflow of the OLED organic material ink in the overlapping area of ​​the first and second defining portions is solved. Attached Figure Description

[0032] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0033] Figure 1 This diagram illustrates the process of creating a pixel-defining layer using existing techniques.

[0034] Figure 2 A cross-sectional schematic diagram of the overlapping region of the first and second defining portions in the prior art is shown.

[0035] Figure 3 This diagram shows a cross-sectional view of a display panel provided in an embodiment of the present invention.

[0036] Figure 4 This diagram illustrates the process of creating a pixel-defining layer according to an embodiment of the present invention.

[0037] Figure 5 Show along Figure 4 A cross-sectional diagram with a dashed line.

[0038] Figure 6 This diagram illustrates the pixel arrangement of a display panel according to an embodiment of the present invention.

[0039] Figure 7 This diagram illustrates the process of creating a pixel-defining layer according to another embodiment of the present invention.

[0040] Figure 8 A schematic diagram of a mask plate showing an opening or blocking portion extending in a second direction.

[0041] Figure 9 Show Figure 7 A schematic diagram of the cross-section along the direction of the dashed line A.

[0042] Figure 10 Show Figure 7 A schematic diagram of the cross-section along the direction of the dashed line B.

[0043] Figure 11 Show Figure 7 A schematic diagram of the cross-section along the direction of the dashed line C. Detailed Implementation

[0044] To more clearly illustrate the present invention, the following description, in conjunction with embodiments and accompanying drawings, further explains the invention. Similar components in the drawings are indicated by the same reference numerals. Those skilled in the art should understand that the specific description below is illustrative rather than restrictive and should not be construed as limiting the scope of protection of the present invention.

[0045] In this invention, "on," "formed on," and "set on" can mean that one layer is directly formed or set on another layer, or that one layer is indirectly formed or set on another layer, meaning that there are other layers between the two layers.

[0046] It should be noted that although the terms "first," "second," etc., may be used herein to describe various components, members, elements, regions, layers, and / or portions, these components, members, elements, regions, layers, and / or portions should not be limited by these terms. Rather, these terms are used to distinguish one component, member, element, region, layer, and / or portion from another. Thus, for example, the first component, first member, first element, first region, first layer, and / or first portion discussed below may be referred to as a second component, second member, second element, second region, second layer, and / or second portion without departing from the teachings of the invention.

[0047] In this invention, unless otherwise stated, the term "co-layer arrangement" refers to two layers, components, members, elements, or portions that can be formed by the same fabrication process (e.g., patterning process), and that these two layers, components, members, elements, or portions are generally formed of the same material. For example, co-layer arrangement of two or more functional layers means that these co-layered functional layers can be formed using the same material layer and the same fabrication process, thereby simplifying the fabrication process of the display substrate.

[0048] In this invention, unless otherwise stated, the term "patterning process" generally includes steps such as photoresist coating, exposure, development, etching, and photoresist stripping. The term "one-step patterning process" refers to a process of forming patterned layers, components, or parts using a single photomask.

[0049] Currently, inkjet printing is one way to create the light-emitting layer of OLED (Organic Light Emitting Diode) display devices. It uses a solvent to melt the OLED organic material and then directly prints the melted OLED organic material onto the surface of the display back panel to form the light-emitting layer.

[0050] During the inkjet printing drying process, the solvent evaporates faster at the edge of the ink droplet. This causes the solvent to flow from the center to the edge, carrying the solute towards the edge of the droplet, eventually reaching the edge, which is close to the edge of the pixel pit. At the edge of the pixel pit, the ink droplet climbs along the hydrophilic material interface at the bottom of the pixel boundary layer to the hydrophobic surface within the pixel boundary layer. The thicker the pixel boundary layer, the higher the droplet climbs, resulting in a deposition morphology that is thick at the edges and thin at the center, known as the "coffee ring effect." This leads to uneven film formation within the pixel opening, resulting in uneven light emission from the pixel units.

[0051] To improve the uniformity of pixel units within a pixel aperture along its long axis, existing technology proposes a display panel whose pixel defining layer includes a continuous line bank. The fabrication process is as follows: Figure 1 As shown, a first hydrophilic defining portion 10 of the pixel defining layer is first fabricated on a planarization layer using a patterning process such as coating and photolithography. The thickness of the first defining portion 10 is less than 1 μm. Then, a second hydrophobic defining portion 20 of the pixel defining layer, at least at the end furthest from the substrate, is fabricated on the first defining portion 10 using a patterning process such as coating and photolithography. The thickness of the second defining portion 20 is 1.2 μm-1.5 μm. When inkjet printing is performed on this substrate, ink only needs to be printed onto the display area 30. Because the first defining portion 10 is hydrophilic, the entire column of ink will connect into a single column, thereby improving the uniformity of the OLED organic material ink in the long axis direction. The inventors discovered that due to the leveling properties of the liquid, this structure, when coating the material of the second defining portion 20, such as... Figure 2 As shown, the thickness of the second defining portion 20 corresponding to the overlapping region 40 (i.e., the second defining portion 20 formed on the first defining portion 10, or the second defining portion 20 overlapping with the first defining portion 10) is significantly smaller than the thickness of the second defining portion 20 corresponding to the display region 30 (i.e., the second defining portion 20 directly formed on the planarization layer). For example, if the thickness of the second defining portion 20 corresponding to the display region 30 is 1.2 μm, then the thickness of the second defining portion 20 corresponding to the overlapping region 40 is only about 0.8 μm. Therefore, the hydrophobic effect of the second defining portion 20 at the overlapping region 40 is relatively poor, which makes it easy for OLED organic material ink to overflow at the overlapping region 40.

[0052] In view of this, the present invention provides a display panel, a display device, and a method for manufacturing the same.

[0053] The following describes the preparation method of the display panel, the display panel and the display device of some embodiments of the present invention through several specific examples.

[0054] Example 1

[0055] One embodiment of the present invention provides a method for manufacturing a display panel, and a cross-sectional schematic diagram of the display panel is shown below. Figure 3 As shown, the preparation method includes:

[0056] Step S1: Provide a substrate 200. For example, when the OLED array substrate is a flexible array substrate, the provided substrate 200 can be polyimide (PI), polyethylene naphthalate (PEN), thermoplastic polyester (PET), etc.; when the OLED array substrate is a rigid array substrate, the substrate 200 can be a rigid material such as glass or quartz.

[0057] Step S2, forming the driving circuit layer or thin-film transistor layer, includes:

[0058] An active layer 2051 is formed on a substrate 200 using a patterning process; a gate insulating layer 2052 is formed on the active layer 2051 by deposition or other means; a gate 2053 is formed on the gate insulating layer 2052 using a patterning process; an interlayer dielectric layer 2054 is formed on the gate by deposition or other means; then, the interlayer dielectric layer 2054 is etched to form a via exposing the active layer 2051.

[0059] After the via is formed in the interlayer dielectric layer 2054, a source 2055A and a drain 2055B are formed, as well as a signal line 2056 electrically connected to one of the source or drain (shown in the figure as electrically connected to the drain 2055B).

[0060] The active layer can be made of materials such as polycrystalline silicon and metal oxides, the gate insulating layer can be made of inorganic insulating materials such as silicon oxide, silicon nitride, or silicon oxynitride, and the interlayer dielectric layer can be made of inorganic insulating materials such as silicon oxide, silicon nitride, or silicon oxynitride. The gate material includes metals or alloys such as aluminum, titanium, and cobalt. During fabrication, a gate material layer is first formed using methods such as sputtering or evaporation, and then a patterning process is performed on the gate material layer to form a patterned gate.

[0061] Preferably, a barrier layer 201 and a buffer layer 202 are formed on the substrate before the active layer is formed. For example, the barrier layer and the buffer layer can be formed on the entire surface of the substrate. For example, the barrier layer can be made of an inorganic insulating material such as silicon oxide, silicon nitride, or silicon oxynitride, and the buffer layer can also be made of an inorganic insulating material such as silicon oxide, silicon nitride, or silicon oxynitride. The barrier layer helps to prevent water and oxygen from entering the OLED formed from the bottom. The buffer layer is beneficial to the quality of subsequent material deposition.

[0062] The embodiments of the present invention do not limit the materials of each functional layer, and the materials of each functional layer are not limited to the examples described above. The fabrication of the thin-film transistor structure is now complete.

[0063] Those skilled in the art will understand that the above-described thin-film transistor uses a top-gate structure as an example, but the present invention is not limited thereto, and a bottom-gate structure is also included within the scope of the present invention.

[0064] Step S3: Form a planarization layer 2057.

[0065] Specifically, a planarization layer material, such as an organic material, with a thickness of about 1 to 3 μm is deposited to cover the above-mentioned film layers. Then, a patterning process is used to pattern the film layers to form an opening at the position corresponding to the other of the above-mentioned source and drain electrodes (the source electrode in the figure).

[0066] Step S4: Forming a light-emitting device layer, including:

[0067] Step S41: Deposit the anode metal layer of the OLED in the opening of the planarization layer 2057 and pattern it to form an anode 2058A (the anode 2058A is connected to the source 2055A). For example, the anode material includes metal oxides such as ITO and IZO or metals such as Ag, Al, and Mo or their alloys. The shape of the anode ITO is consistent with the shape of the sub-pixel and is approximately rectangular.

[0068] Step S42: A pixel defining layer 2059 is formed around the anode using a patterning process, i.e., the pixel defining layer 2059 is formed on the planarization layer 2057. The structure of the pixel defining layer 2059 is as follows: Figure 4 As shown, the pixel defining layer 2059 includes a first defining portion 91 and a plurality of second defining portions 92. The second defining portions 92 extend along a second direction, such as a vertical direction. The first defining portion 91 includes a plurality of first portions 911 extending along a first direction, such as a horizontal direction, and a plurality of second portions 912 extending along a second direction, such as a vertical direction. The first defining portion 91 is closer to the substrate 200 than the second defining portions 92. The first defining portion 91 is hydrophilic, and at least a portion of the second defining portion 92 is hydrophobic, the at least a portion including an end away from the substrate 200. The second defining portion 92 has a substantially uniform second thickness, the thickness of the first defining portion 91 is a first thickness, and the second thickness is greater than the first thickness.

[0069] This invention addresses the problems of existing technologies by providing a display panel, a display device, and a method for manufacturing the same. The display panel, by providing a second defining portion with a substantially uniform second thickness, improves the uniformity of the OLED organic material ink in the second direction while simultaneously solving the problem of ink overflow in the overlapping area of ​​the first and second defining portions. Furthermore, it improves the uniformity of the OLED organic material ink in the second direction, easily achieves a substantially uniform second thickness in the second defining portion, and features a simple process suitable for mass production.

[0070] In one possible implementation, forming a pixel defining layer 2059 on the planarization layer 2057 includes:

[0071] On the planarization layer, a plurality of first portions 911 extending along a first direction, such as a horizontal direction, and a plurality of second portions 912 extending along a second direction, such as a vertical direction, are formed of a first defining portion 91.

[0072] Multiple second defining portions 92 extending in a second direction, such as a vertical direction, are formed on the multiple second portions 912 extending in a second direction, such as a vertical direction.

[0073] In a specific example, the process of creating a pixel boundary layer is as follows: Figure 4 As shown, firstly, a plurality of first portions 911 extending horizontally of a first defining portion 91 with hydrophilicity of the pixel defining layer are fabricated on a planarization layer by a patterning process such as coating and photolithography. Then, a plurality of second portions 912 extending vertically of the first defining portion 91 with hydrophilicity of the pixel defining layer are fabricated on the first portions 911 by a patterning process such as coating and photolithography. The thickness of the hydrophilic solution in the first portions 911 and the second portions 912 is a first thickness, which is less than 1 μm, for example, 0.6 μm-1 μm. Then, a plurality of second defining portions 92 extending vertically of the pixel defining layer at least at the end away from the substrate are fabricated on the second portions 912 by a patterning process such as coating and photolithography. The solution at the second portion 912 adjacent to the first defining portion 91 is hydrophilic, and the solution at the end of the second defining portion 92 away from the substrate 200 is hydrophobic. The thickness of the second defining portion 92 is a second thickness, which is 1.2 μm-1.5 μm.

[0074] In one possible implementation, the projection of each of the second portions 912 onto the substrate 200 overlaps the projection of one of the second defining portions 92 onto the substrate 200.

[0075] In one possible implementation, the projection of each of the second portions 912 onto the substrate 200 coincides with the projection of a second defining portion 92 onto the substrate 200.

[0076] Continuing with the example above, Figure 5 It shows Figure 4 A cross-sectional diagram along the dotted line shows that during manufacturing, the adhesive material of the second defining portion 92, which is coated across the entire surface, will be lower in the display area 930 than at the overlapping area 940 of the first defining portion 91 and the second defining portion 92. Figure 5 The thickness of the adhesive material in the second defining portion 92 of the display area 930 is about 1.6 μm. The thickness at the overlapping area 940 of the first defining portion 91 and the second defining portion 92 is 0.6 μm plus 1.2 μm, for a total of 1.8 μm. However, after the display area 930 is exposed and developed, all the adhesive material in the second defining portion 92 of the display area 930 is removed, leaving only the first thickness of the first defining portion 91 and the roughly uniform second thickness of the second defining portion 92 above the second portion 912 of the first defining portion 91.

[0077] This implementation method makes it easy to achieve a second thickness with a roughly uniform second defining part, and the process is simple and easy to mass-produce.

[0078] For example, the material of the pixel defining layer may include organic insulating materials such as negative photoresist, polyimide, and epoxy resin;

[0079] Step S43: A light-emitting layer 2058B is formed on the anode 2058A in the opening of the pixel defining layer 2059 by inkjet printing or vapor deposition, wherein the material of the light-emitting layer is an organic material.

[0080] For example, HIL ink is printed onto a pixel area. Because the ink flows within the pixel area, the ink can be evenly distributed throughout the entire column. Ink drying only occurs at the very edges of the column of pixels, while the middle sub-pixels achieve uniform film formation. It should be noted that although the entire column is connected, an anode is formed only at the corresponding sub-pixel positions; therefore, sub-pixels along the column direction can be divided.

[0081] Step S44: Forming cathode 2058C. Cathode 2058C is formed on the entire surface of the OLED array substrate, for example. The cathode material may include metals such as Mg, Ca, Li or Al or their alloys, or metal oxides such as IZO or ZTO, or organic materials with conductive properties such as PEDOT / PSS (poly(3,4-ethylenedioxythiophene / polystyrene sulfonate)).

[0082] In this configuration, the anodes corresponding to each pixel are isolated from each other, while the cathodes corresponding to each pixel are connected to each other.

[0083] An auxiliary light-emitting layer that facilitates the emission of the light-emitting layer can also be formed between the anode 2058A and the light-emitting layer 2058B, and between the light-emitting layer 2058B and the cathode 2058C. This auxiliary light-emitting layer may include one or more of an electron transport layer, an electron injection layer, a hole transport layer, and a hole injection layer. For example, the auxiliary light-emitting layer may be an organic material layer.

[0084] S5. After the OLED device is formed, an encapsulation layer can be formed. For example, the encapsulation layer consists of a first inorganic encapsulation layer 220A, an organic encapsulation layer 220B, and a second inorganic encapsulation layer 220C.

[0085] For example, the first and second inorganic encapsulation layers are formed by deposition or other methods. The organic encapsulation layer is formed by inkjet printing.

[0086] For example, the first and second inorganic encapsulation layers can be formed using inorganic materials such as silicon nitride, silicon oxide, and silicon oxynitride, while the organic encapsulation layer can be formed using organic materials such as polyimide (PI) and epoxy resin. Thus, the first inorganic encapsulation layer, the organic encapsulation layer, and the second inorganic encapsulation layer form a composite encapsulation layer. This composite encapsulation layer provides multiple layers of protection for the functional structure of the display area, resulting in better encapsulation performance.

[0087] In some embodiments of the present invention, other necessary functional film layers may be formed in the display area and the isolation area as needed, such as storage capacitors in the display area. These film layers can be formed using conventional methods, which will not be described in detail here.

[0088] The embodiments of the present invention do not limit the materials of each functional layer, and the materials of each functional layer are not limited to the examples above.

[0089] Example 2

[0090] Another embodiment of the present invention provides a display panel, which can be fabricated using the fabrication method described in Embodiment 1, such as... Figure 3 and Figure 4 As shown, the display panel includes:

[0091] A substrate 200, and a driving circuit layer, a planarization layer 2057, and a pixel defining layer 2059 sequentially stacked on the substrate; the pixel defining layer 2059 includes a first defining portion 91 and a plurality of second defining portions 92, the first defining portion 91 including a plurality of first portions 911 extending along a first direction, such as a horizontal direction, and a plurality of second portions 912 extending along a second direction, such as a vertical direction, the second defining portions 92 extending along the second direction, such as a vertical direction, the first defining portion 91 being closer to the substrate 200 than the second defining portion 92; the first defining portion 91 is hydrophilic, at least a portion of the second defining portion 92 is hydrophobic, the at least a portion including an end away from the substrate 200; the second defining portion 92 has a substantially uniform second thickness, the thickness of the first defining portion 91 is a first thickness, and the second thickness is greater than the first thickness.

[0092] In one possible implementation, the first thickness is 0.6 μm-1 μm and the second thickness is 1.2 μm-1.5 μm.

[0093] In one possible implementation, the projection of each of the second portions onto the substrate overlaps the projection of one of the second defining portions onto the substrate.

[0094] In one possible implementation, the projection of each of the second portions onto the substrate coincides with the projection of a second defining portion onto the substrate.

[0095] In one possible implementation, the display panel further includes a plurality of sub-pixels arranged in an array. The sub-pixels are disposed in the opening defined by the first part 911 and the second defining part 92. Due to process and design reasons, the sub-pixels are roughly rectangular. The four corners of the rectangle are not right angles, but rounded corners with a very small radius. Therefore, the overlapping area of ​​the second defining layer and the first defining layer will have a certain curvature.

[0096] A subpixel is a light-emitting device capable of emitting a single color. During display on the display panel, color display is achieved by controlling the emission of different colored subpixels and mixing the different colors of light. In embodiments of the present invention, such as... Figure 6 As shown, the sub-pixels include a first sub-pixel 1, a second sub-pixel 2, and a third sub-pixel 3. The first sub-pixel 1 is an R sub-pixel that emits red light, the second sub-pixel 2 is a G sub-pixel that emits green light, and the third sub-pixel 3 is a B sub-pixel that emits blue light. The first sub-pixel 1 forms a first sub-pixel row along a second direction, such as a vertical direction, the second sub-pixel 2 forms a second sub-pixel row along a second direction, such as a vertical direction, and the third sub-pixel 3 forms a third sub-pixel row along a second direction, such as a vertical direction.

[0097] Example 3

[0098] Another embodiment of the present invention provides a method for manufacturing a display panel, the method comprising:

[0099] Steps S1-S2 are the same as those provided in Embodiment 1 of the present invention, and will not be repeated here.

[0100] Step S3': Form a planarization layer.

[0101] Specifically, a planarization layer material, such as an organic material, with a thickness of about 1 to 3 μm is deposited to cover the above-mentioned film layers. Multiple grooves arranged in an array are formed on the planarization layer, and the depth of the grooves is approximately equal to the first thickness; for example, the depth of the grooves is 0.6 μm to 1 μm.

[0102] Then, using patterning techniques, it is patterned to form an opening at the position corresponding to the other of the aforementioned source and drain electrodes (the source electrode in the figure).

[0103] Step S4': Forming a light-emitting device layer, including:

[0104] Step S41': Deposit the anode metal layer of the OLED in the opening of the planarization layer and pattern it to form an anode (the anode is connected to the source). For example, the anode material includes metal oxides such as ITO and IZO or metals such as Ag, Al, and Mo or their alloys. The shape of the anode ITO is consistent with the shape of the sub-pixel and is approximately rectangular.

[0105] Step S42': A pixel delimiting layer is formed around the anode using a patterning process; that is, a pixel delimiting layer is formed on the planarization layer. The structure of the pixel delimiting layer is as follows: Figure 7As shown, the pixel defining layer includes a first defining portion 91' and a plurality of second defining portions 92'. The second defining portions 92' extend along a second direction, such as a vertical direction. The first defining portion 91' includes a plurality of first portions 911' extending along a first direction, such as a horizontal direction. The first defining portion 91' is closer to the substrate than the second defining portions 92'. The first defining portion 91' is hydrophilic, and at least a portion of the second defining portion 92' is hydrophobic, the at least a portion including an end away from the substrate. The second defining portion 92' has a substantially uniform second thickness, the thickness of the first defining portion 91' is a first thickness, and the second thickness 92' is greater than the first thickness.

[0106] In one possible implementation, forming a pixel-defining layer on the planarization layer includes:

[0107] A pixel defining layer adhesive material using a bonding-type hydrophobic material is coated on the planarization layer, and the thickness of the pixel defining layer adhesive material corresponding to the non-groove portion of the planarization layer is the second thickness;

[0108] Using a mask having an opening or blocking portion extending in a second direction, photolithography is performed on the pixel defining layer adhesive material to a second thickness to form the first portion and the second defining portion, wherein the first portion includes a plurality of discontinuously arranged first sub-parts disposed in the groove.

[0109] In a specific example, when fabricating the planarization layer above the light-emitting device layer, the depth of the multiple grooves arranged in an array on the planarization layer is a first thickness, for example, 0.6μm-1μm. When the pixel defining layer adhesive material of bonding type hydrophobic material is coated all over the planarization layer forming multiple grooves, the coated pixel defining layer is approximately uniform at the ends away from the planarization layer. The thickness of the pixel defining layer adhesive material corresponding to the non-grooved portion of the planarization layer is a second thickness, for example, 1.2μm-1.5μm. At this time, the thickness of the pixel defining layer adhesive material corresponding to the grooved portion of the planarization layer is 1.8μm-2.5μm. In this case, the hydrophobic substance of the bonding type hydrophobic material is uniformly distributed inside the adhesive material, and the pixel defining layer coated all over the planarization layer is hydrophobic.

[0110] Utilize Figure 8 When the mask plate shown has an opening or blocking portion extending in the second direction is exposed and developed, the pixel boundary layer of the exposed area of ​​the display area is stripped away, leaving only the anode ITO, as shown. Figure 9 As shown, the planarization layer is represented by 10', the anode by 20', the pixel defining layer adhesive material coated across the entire surface by 90', and the first defining portion by 91'. Figure 9 Show Figure 7A cross-sectional schematic diagram along the direction of the dashed line A shows that the exposure area at the first boundary is relatively thick due to the pixel boundary layer adhesive material, leaving a residue of about 0.6μm-1μm inside the hole, which can prevent leakage and separate pixels; in addition, it can also improve the ink climbing situation at the first boundary.

[0111] Utilize Figure 8 When the mask plate shown has an opening or blocking portion extending in the second direction is exposed and developed, a second thickness of photolithography is performed on the pixel defining layer adhesive material coated all over the planarization layer to form the first portion and the second defining portion, such as... Figure 10 As shown, the planarization layer is represented by 10', the pixel-defining adhesive layer coated across the entire surface is represented by 90', the first defining portion is represented by 91', and the second defining portion is represented by 92'. Figure 10 Show Figure 7 A cross-sectional diagram along the direction of dashed line B shows that the second defining part is the pixel defining layer left in the occlusion area, which is about 1.2μm-1.5μm. Since the pixel defining layer adhesive material is generally hydrophobic and floats on the surface, the hydrophobic layer is generally 0.3μm on the surface of the pixel defining layer. Therefore, the 0.6μm-1μm pixel defining layer adhesive material left in the first defining part has hydrophilic properties, while the 1.2μm-1.5μm pixel defining layer adhesive material left in the second defining part has hydrophobic properties.

[0112] Utilize Figure 8 When the mask plate shown has an opening or blocking portion extending in the second direction is exposed and developed, such as... Figure 11 As shown, the planarization layer is represented by 10', the anode by 20', the pixel defining layer adhesive material coated across the entire surface by 90', and the second defining portion by 92'. Figure 11 Show Figure 7 A cross-sectional schematic diagram along the direction of the dashed line C shows that a 1.2μm-1.5μm hydrophobic pixel defining layer adhesive is left in the second defining region.

[0113] This implementation method involves creating multiple grooves arranged in an array on the planarization layer. The depth of the grooves is approximately equal to the first thickness. This groove method allows for a single exposure and development process, simplifying the process and further improving the uniformity of the pixel openings in the second direction. Since the first part is located in the groove, there are no protrusions in the first defining layer. When using a mask with an opening or shielding portion extending in the second direction for exposure and development, the pixel defining layer adhesive material coated on the entire planarization layer is photolithographically etched to a second thickness to form the first part and the second defining part. When using inkjet printing to prepare each film layer of the organic light-emitting functional layer, the problem of ink overflow in the overlapping area of ​​the first and second defining parts can be improved while enhancing the uniformity in the second direction.

[0114] For example, the material of the pixel defining layer may include organic insulating materials such as negative photoresist, polyimide, and epoxy resin;

[0115] Step S43': A light-emitting layer is formed on the anode in the opening of the pixel defining layer by means of inkjet printing or vapor deposition, wherein the material of the light-emitting layer is an organic material;

[0116] For example, HIL ink is printed onto the pixel area. Since the ink in the pixel area is fluid, the ink in the entire column can be evenly distributed. The ink dries only at the outermost edge of the column of pixels, and the middle sub-pixels obtain a uniform film.

[0117] Step S44': Forming a cathode. The cathode is formed on the entire surface of the OLED array substrate, for example. The cathode material may include metals such as Mg, Ca, Li or Al or their alloys, or metal oxides such as IZO or ZTO, or organic materials with conductive properties such as PEDOT / PSS (poly(3,4-ethylenedioxythiophene / polystyrene sulfonate)).

[0118] In this configuration, the anodes corresponding to each pixel are isolated from each other, while the cathodes corresponding to each pixel are connected to each other.

[0119] An auxiliary light-emitting layer that facilitates the emission of light from the light-emitting layer can also be formed between the anode and the light-emitting layer, and between the light-emitting layer and the cathode. This auxiliary light-emitting layer may include one or more of the following: an electron transport layer, an electron injection layer, a hole transport layer, and a hole injection layer. For example, an organic material layer may be used as the auxiliary light-emitting layer.

[0120] S5' After the OLED device is formed, an encapsulation layer can be formed. For example, the encapsulation layer consists of a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer.

[0121] For example, the first and second inorganic encapsulation layers are formed by deposition or other methods. The organic encapsulation layer is formed by inkjet printing.

[0122] For example, the first and second inorganic encapsulation layers can be formed using inorganic materials such as silicon nitride, silicon oxide, and silicon oxynitride, while the organic encapsulation layer can be formed using organic materials such as polyimide (PI) and epoxy resin. Thus, the first inorganic encapsulation layer, the organic encapsulation layer, and the second inorganic encapsulation layer form a composite encapsulation layer. This composite encapsulation layer provides multiple layers of protection for the functional structure of the display area, resulting in better encapsulation performance.

[0123] In some embodiments of the present invention, other necessary functional film layers may be formed in the display area and the isolation area as needed, such as storage capacitors in the display area. These film layers can be formed using conventional methods, which will not be described in detail here.

[0124] The embodiments of the present invention do not limit the materials of each functional layer, and the materials of each functional layer are not limited to the examples above.

[0125] Example 4

[0126] Another embodiment of the present invention provides a display panel, which can be prepared using the preparation method described in Embodiment 3, such as... Figure 7 The display panel includes:

[0127] A substrate, and a driving circuit layer, a planarization layer, and a pixel defining layer sequentially stacked on the substrate; the pixel defining layer includes a first defining portion 91' and a plurality of second defining portions 92', the first defining portion 91' including a plurality of first portions 911' extending along a first direction, such as a horizontal direction, and the second defining portions 92' extending along a second direction, such as a vertical direction, the horizontal direction intersecting the vertical direction; the first defining portion 91' is closer to the substrate than the second defining portions 92'; the first defining portion 91' is hydrophilic, and at least a portion of the second defining portion 92' is hydrophobic, the at least a portion including an end away from the substrate; the second defining portion 92' has a substantially uniform second thickness, the thickness of the first defining portion 91' is a first thickness, and the second thickness is greater than the first thickness.

[0128] In one possible implementation, the first thickness is 0.6 μm-1 μm and the second thickness is 1.2 μm-1.5 μm.

[0129] In one possible implementation, the planarization layer is provided with a plurality of arrayed grooves, the first portion including a plurality of discontinuously arranged first sub-portions disposed in the grooves.

[0130] In one possible implementation, the depth of the first groove is approximately equal to the first thickness.

[0131] In one possible implementation, the display panel further includes a plurality of sub-pixels arranged in an array. The sub-pixels are disposed in the opening defined by the first portion 911' and the second defining portion 92'. Due to process and design reasons, the sub-pixels are roughly rectangular. The four corners of the rectangle are not right angles, but rounded corners with a very small radius. Therefore, the overlapping area of ​​the second defining layer and the first defining layer will have a certain curvature.

[0132] A subpixel is a light-emitting device capable of emitting a single color. During display on a display panel, color display is achieved by controlling the emission of different colored subpixels and mixing the different colors of light. In this embodiment of the invention, the subpixel includes a first subpixel, a second subpixel, and a third subpixel. The first subpixel is an R subpixel capable of emitting red light, the second subpixel is a G subpixel capable of emitting green light, and the third subpixel is a B subpixel capable of emitting blue light. The first subpixel forms a first subpixel row along a second direction, such as a vertical direction; the second subpixel forms a second subpixel row along a second direction, such as a vertical direction; and the third subpixel forms a third subpixel row along a second direction, such as a vertical direction.

[0133] Example 5

[0134] Another embodiment of the present invention provides a display device, including the display panel provided in Embodiment 2 or the display panel provided in Embodiment 4. The display device can be any product or component with display function, such as electronic paper, mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, or navigator; this embodiment does not limit this.

[0135] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A display panel, characterized by, The display panel comprises: a substrate, and a driving circuit layer, a planarization layer and a pixel defining layer which are sequentially arranged on the substrate; the pixel defining layer comprises a first defining portion and a plurality of second defining portions, the first defining portion comprises a plurality of first portions extending along a first direction, the second defining portions extend along a second direction, the first direction intersects the second direction; the first defining portion is closer to the substrate than the second defining portion; the first defining portion has a liquid affinity, at least part of the second defining portion has a liquid repellency, the at least part comprises an end portion away from the substrate; the second defining portion has a substantially uniform second thickness, the first defining portion has a first thickness, and the second thickness is greater than the first thickness; the first defining portion further comprises a plurality of second portions extending along the second direction, and each of the second portions covers a projection of the second defining portion on the substrate; the planarization layer is provided with a plurality of arrayed grooves, the first portion comprises a plurality of first sub-portions arranged intermittently, and the first sub-portions are arranged in the grooves; the depth of the grooves is substantially equal to the first thickness.

2. The display panel of claim 1, wherein, The projection of each of the second portions on the substrate coincides with the projection of the second defining portion on the substrate.

3. The display panel of claim 1, wherein, The first thickness is 0.6 μm-1 μm, and the second thickness is 1.2 μm-1.5 μm.

4. The display panel of any one of claims 1-3, wherein, The display panel further comprises a plurality of sub-pixels arranged in an array, the sub-pixels are arranged in openings defined by the first portions and the second defining portions, the sub-pixels comprise first sub-pixels, second sub-pixels and third sub-pixels, the first sub-pixels form a first sub-pixel row along the second direction, the second sub-pixels form a second sub-pixel row along the second direction, and the third sub-pixels form a third sub-pixel row along the second direction.

5. A display device, characterized by comprising: The display panel comprises any one of claims 1-4.

6. A method for producing a display panel as claimed in any one of claims 1 to 4, characterized in that The display panel comprises: providing a substrate; sequentially forming a driving circuit layer on the substrate; forming a planarization layer on the driving circuit layer; and forming a pixel defining layer on the planarization layer; wherein the pixel defining layer comprises a first defining portion and a plurality of second defining portions, the first defining portion comprises a plurality of first portions extending along a first direction, the second defining portions extend along a second direction, the first direction intersects the second direction; the first defining portion is closer to the substrate than the second defining portion; the first defining portion has a liquid affinity, at least part of the second defining portion has a liquid repellency, the at least part comprises an end portion away from the substrate; the second defining portion has a uniform second thickness, the first defining portion has a first thickness, and the second thickness is greater than the first thickness.

7. The production method according to claim 6, wherein The forming of the pixel defining layer on the planarization layer comprises: forming a plurality of first portions of the first defining portion extending along the first direction and a plurality of second portions of the first defining portion extending along the second direction on the planarization layer; and forming a plurality of second defining portions extending along the second direction on the plurality of second portions extending along the second direction.

8. The preparation method according to claim 6, characterized in that, The forming of the pixel defining layer on the planarization layer comprises: a plurality of grooves arranged in an array are formed on the planarization layer, and a depth of the grooves is substantially equal to the first thickness; a pixel definition layer glue material using a bonding type lyophobic material is coated on the planarization layer, and a thickness of the pixel definition layer glue material corresponding to a non-groove portion of the planarization layer is the second thickness; photolithography of the second thickness is performed on the pixel definition layer glue material by using a mask plate having openings or shielding portions extending along a second direction, so as to form the first portion and the second definition portion, wherein the first portion includes a plurality of first sub-portions arranged in an array, and the first sub-portions are arranged in the grooves.

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