Display mother board and preparation method thereof, preparation method of display panel and display device

Abstract

The embodiment of the invention provides a display mother board and a preparation method thereof, a preparation method of a display panel and a display device, and relates to the technical field of display, the display mother board comprises a substrate, a pixel defining layer, a light emitting unit, an alignment mark and a light absorption layer; the pixel defining layer is located on one side of the substrate, a pixel opening is defined by the pixel defining layer, and at least part of the light-emitting unit is located in the pixel opening; the alignment mark is located in the substrate and / or on the substrate; the light absorption layer is located on the side, away from the substrate, of the alignment mark and covers at least part of the alignment mark. According to the display mother set, the color difference between the alignment mark and the alignment mark on the mask can be larger, so that the alignment between the alignment mark and the alignment mark on the mask can be more accurate, and the quality of the display mother set can be improved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular, to a display motherboard and a method for preparing the same, a method for preparing a display panel, and a display device. Background Art

[0002] Organic Light Emitting Diode (OLED) and flat panel display devices based on technologies such as Light Emitting Diode (LED) have been widely used in various consumer electronic products such as mobile phones, televisions, laptops, desktop computers, etc. due to their advantages such as high image quality, power saving, thin body and wide application range, becoming the mainstream in display panels.

[0003] However, there are still some problems with display panels that need to be solved urgently. Summary of the invention

[0004] In order to overcome the technical problems mentioned in the above technical background, an embodiment of the present application provides a display motherboard, wherein the display motherboard comprises:

[0005] substrate;

[0006] A pixel defining layer, located on one side of the substrate, wherein the pixel defining layer defines a pixel opening;

[0007] a light emitting unit, at least a portion of which is located within the pixel opening;

[0008] an alignment mark located in and / or on the substrate;

[0009] The light absorbing layer is located on a side of the alignment mark away from the substrate, and the light absorbing layer covers at least a portion of the alignment mark.

[0010] In some possible implementations, the light absorbing layer covers a side of the alignment mark away from the substrate and covers a side wall of the alignment mark;

[0011] Preferably, along the thickness direction of the substrate, the thickness of the light absorption layer is greater than or equal to 0.5 μm and less than or equal to 1.5 μm.

[0012] In some possible implementations, the color of the material of the light absorbing layer includes black, and the color of the alignment mark includes white; or the color of the material of the light absorbing layer includes white, and the color of the alignment mark includes black.

[0013] In some possible implementations, the material of the light absorbing layer includes a metal material, an inorganic material or an organic material;

[0014] Preferably, the material of the light absorbing layer includes at least one of metal chromium, metal manganese or metal chromium-manganese alloy;

[0015] Preferably, the color of the metal material, inorganic material or organic material is black.

[0016] In some possible implementations, the light-emitting unit includes a first electrode, a light-emitting functional layer, and a second electrode stacked in sequence in a direction away from the substrate, and the substrate includes a transparent substrate and a plurality of metal layers located on one side of the transparent substrate and stacked in sequence in a direction away from the transparent substrate; the alignment mark is in the same layer and material as the first electrode, and / or the alignment mark is in the same layer and material as any one of the plurality of metal layers;

[0017] Preferably, the material of the first electrode includes three layers of indium tin oxide, silver and indium tin oxide stacked in sequence;

[0018] Preferably, the material of the metal layer includes three layers of titanium, aluminum and titanium or three layers of molybdenum, aluminum and molybdenum stacked in sequence;

[0019] Preferably, the substrate further comprises a planarization layer located between the transparent substrate and the alignment mark.

[0020] In some possible implementations, the alignment marks are in multiple groups, and each group of the alignment marks includes a first alignment sub-mark and a second alignment sub-mark;

[0021] Preferably, the orthographic projection of the first pair of sub-marks on the substrate is a square;

[0022] Preferably, the orthographic projection of the second alignment sub-mark on the substrate is in the shape of a cross.

[0023] In some possible implementations, the display motherboard includes a functional area and a frame area surrounding at least a portion of the functional area, and the alignment mark is located in the frame area;

[0024] Preferably, the display motherboard comprises a plurality of display panels arranged at intervals, the plurality of display panels are located in the functional area, the display panel comprises a display area and a non-display area surrounding at least a portion of the display area, a cutting path is defined between the non-display areas of two adjacent display panels, and the light emitting unit is located in the display area;

[0025] Preferably, the light absorbing layer is located in the border area.

[0026] In some possible implementations, the present application further provides a method for preparing a display motherboard, the method comprising:

[0027] providing a substrate;

[0028] forming a conductive layer and an alignment mark on one side of the substrate;

[0029] forming a light absorbing layer covering the alignment mark on a side of the alignment mark away from the substrate;

[0030] forming a pixel defining layer on a side of the conductive layer away from the substrate, wherein the pixel defining layer defines a pixel opening;

[0031] Aligning the alignment mark on the mask plate with the alignment mark on the display master;

[0032] The light-emitting functional layer and the second electrode layer of the light-emitting unit are sequentially formed in the pixel opening through the mask plate, and at least part of the film layer in the light-emitting functional layer and the second electrode layer extend to the side of the pixel defining layer away from the substrate.

[0033] In some possible implementations, the present application further provides a method for preparing a display panel, the method comprising:

[0034] providing a substrate;

[0035] forming a conductive layer and an alignment mark on one side of the substrate;

[0036] forming a light absorbing layer covering the alignment mark on a side of the alignment mark away from the substrate;

[0037] forming a pixel defining layer on a side of the conductive layer away from the substrate, wherein the pixel defining layer defines a pixel opening;

[0038] Aligning the alignment mark on the mask plate with the alignment mark on the display master;

[0039] The light-emitting functional layer and the second electrode layer of the light-emitting unit are sequentially formed in the pixel opening by the mask plate to form a display motherboard, wherein the display motherboard includes a functional area and a frame area surrounding at least part of the functional area, the alignment mark is located in the frame area, the display motherboard includes a plurality of display panels arranged at intervals, the plurality of display panels are located in the functional area, the display panel includes a display area and a non-display area surrounding at least part of the display area, a cutting path is defined between the non-display areas of two adjacent display panels, and the light-emitting unit is located in the display area;

[0040] The display motherboard is cut along the cutting path, and the frame area of ​​the display motherboard with the alignment mark is cut off to form a plurality of display panels.

[0041] In some possible embodiments, the present application also provides an electronic device, which includes the display motherboard described in the present application, or includes a display motherboard prepared by the display motherboard preparation method described in the present application, or includes a display panel prepared by the display panel preparation method described in the present application.

[0042] Compared with the prior art, this application has the following beneficial effects:

[0043] The present application provides a display motherboard and a preparation method thereof, a display panel preparation method and a display device. By forming a light-absorbing layer covering at least a portion of the alignment mark on the side of the alignment mark away from the substrate, the color difference between the alignment mark and the alignment mark on the mask can be made greater, thereby making the alignment between the alignment mark and the alignment mark on the mask more precise, thereby improving the quality of the display motherboard. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 One of the top view schematic diagrams of the display motherboard provided in the embodiment of the present application;

[0046] Figure 2 Provided in the embodiments of this application Figure 1 Schematic cross-sectional view at AA in the middle;

[0047] Figure 3 Provided in the embodiments of this application Figure 1 A schematic cross-sectional view of the middle BB;

[0048] Figure 4 The second schematic top view of the display motherboard provided in the embodiment of the present application;

[0049] Figure 5 Provided in the embodiments of this application Figure 4 Schematic cross-sectional view at CC in the middle;

[0050] Figure 6 Provided in the embodiments of this application Figure 4 One of the cross-sectional views at DD in the middle;

[0051] Figure 7 Provided in the embodiments of this application Figure 4 The second cross-sectional view at DD in the middle;

[0052] Figure 8 A schematic diagram of a process for preparing a display motherboard provided in an embodiment of the present application;

[0053] Fig. 9 A cross-sectional schematic diagram of forming a first electrode and an alignment mark on one side of a substrate provided in an embodiment of the present application;

[0054] Fig.10 A cross-sectional schematic diagram of a light absorbing layer covering an alignment mark formed on a side of the alignment mark away from a substrate provided in an embodiment of the present application;

[0055] Fig.11 A cross-sectional schematic diagram of forming a pixel defining layer on a side of the first electrode away from the substrate provided in an embodiment of the present application;

[0056] Fig.12 A cross-sectional schematic diagram of a light-emitting functional layer and a second electrode layer of a light-emitting unit sequentially formed in a pixel opening according to an embodiment of the present application;

[0057] Fig.13 A schematic diagram of a process for preparing a display panel provided in an embodiment of the present application;

[0058] Fig.14 This is a schematic diagram of a cross section of a display panel formed by cutting a display motherboard along cutting lines provided in an embodiment of the present application.

[0059] Figure numerals: 1. substrate; 2. first electrode; 3. pixel defining layer; 31. pixel opening; 4. light-emitting unit; 5. display motherboard; 6. alignment mark; 61. first alignment sub-mark; 62. second alignment sub-mark; 7. light absorption layer; 8. display panel; 9. cutting road; 10. light-emitting functional layer; 101. hole injection layer; 102. hole transport layer; 103. light-emitting layer; 104. electron transport layer; 105. electron injection layer; 11. second electrode; 2. transparent substrate; 13. planarization layer; 14. first metal layer; 15. second metal layer; 16. third metal layer; 17. fourth metal layer. DETAILED DESCRIPTION

[0060] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0061] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0062] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0063] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "vertical", "horizontal", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0064] It should be noted that, in the absence of conflict, different features in the embodiments of the present application may be combined with each other.

[0065] The display motherboard in the related art includes a substrate, a pixel defining layer located on one side of the substrate, an alignment mark, and a light-emitting unit located in a pixel opening of the pixel defining layer. In the process of forming a partial film layer of the light-emitting unit, in order to ensure the evaporation accuracy of the partial film layer of the light-emitting unit, it is necessary to obtain the alignment mark of the corresponding mask and the alignment mark in the display motherboard through a camera to accurately align the mask and the display motherboard.

[0066] However, in the related art, due to the influence of the display master's own gravity and the reflection of the mask plate wrinkles, the color difference between the alignment mark of the mask plate obtained by the camera based on the grayscale and the alignment mark in the display master is small, so that the camera cannot clearly obtain the alignment mark of the mask plate and the alignment mark in the display master, and cannot accurately align the mask plate and the display master, and further cannot accurately evaporate the relevant film layers of the display master (such as part of the film layer of the light-emitting unit) at the corresponding position, which ultimately affects the quality of the display master.

[0067] In order to solve the above-mentioned technical problems, the inventor innovatively designed the following technical solutions, and the specific implementation solutions of the present application will be described in detail below in conjunction with the accompanying drawings. It should be noted that the defects existing in the solutions in the above-mentioned prior art are the results obtained by the inventor after practice and careful research. Therefore, the discovery process of the above-mentioned technical problems and the solutions proposed in this embodiment below for the above-mentioned problems should all be the contributions made by the inventor to the present application in the process of invention and creation, and should not be understood as the technical content known to those skilled in the art.

[0068] See also Figure 1-Figure 3 This embodiment provides a display motherboard, which includes a substrate 1, a pixel defining layer 3, a light-emitting unit 4, an alignment mark 6 and a light-absorbing layer 7.

[0069] The substrate 1 may include a substrate and a plurality of drive units located on one side of the substrate, and each drive unit may include one or more semiconductor switch devices. The semiconductor switch device may be formed by the cooperation of a plurality of film layers in the substrate 1, for example, the semiconductor switch device may be a thin film transistor formed by the cooperation of a plurality of film layers.

[0070] The pixel defining layer 3 is located on one side of the substrate 1 . The pixel defining layer 3 defines a pixel opening 31 . At least a portion of the light emitting unit 4 is located in the pixel opening 31 .

[0071] The alignment mark 6 is located in and / or on the substrate 1 ; the light absorption layer 7 is located on a side of the alignment mark 6 away from the substrate 1 , and the light absorption layer 7 covers at least a portion of the alignment mark 6 .

[0072] The color of the light-absorbing layer 7 is significantly different from the color of the alignment mark 6. When certain film layers of the display master 5 are evaporated by the vapor deposition machine, such as when the light-emitting functional layer of the light-emitting unit 4 is evaporated, the color of the alignment mark 6 obtained by the camera and the alignment mark on the mask plate are significantly different. The camera can more accurately determine the relative position between the alignment mark 6 on the display master 5 and the alignment mark on the mask plate, thereby making the alignment between the alignment mark 6 on the display master 5 and the alignment mark on the mask plate more accurate, and then the film layer of the display master 5 can be accurately evaporated at the corresponding position by the vapor deposition machine, thereby ultimately improving the quality of the display master 5.

[0073] Based on the above design, in this embodiment, by forming a light absorbing layer 7 covering at least a portion of the alignment mark 6 on the side of the alignment mark 6 away from the substrate 1, the color difference between the alignment mark 6 and the alignment mark on the mask can be made greater, thereby making the alignment between the alignment mark 6 and the alignment mark on the mask more precise, thereby improving the quality of the display master 5.

[0074] For some possible implementations, see Figure 4-Figure 6 The display motherboard 5 includes a functional area GN and a frame area BK surrounding at least a portion of the functional area GN, and the alignment mark 6 is located in the frame area BK.

[0075] Optionally, the light absorbing layer 7 is located in the border area BK.

[0076] The functional area GN has a display function, and the border area BK does not have a display function. In this embodiment, the alignment mark 6 and the light absorbing layer 7 are both arranged in the border area BK, so that the alignment mark 6 and the light absorbing layer 7 do not affect the display of the functional area GN, thereby improving the display effect of the display motherboard 5.

[0077] Preferably, see Figure 4 and Fig.14 The display motherboard includes a plurality of display panels 8 arranged at intervals, the plurality of display panels 8 are located in the functional area GN, the display panel 8 includes a display area AA and a non-display area AB surrounding at least a portion of the display area AA, a cutting path 9 is defined between the non-display areas AB of two adjacent display panels 8, and the light-emitting unit 4 is located in the display area AA.

[0078] After the display master 5 is formed, it can be cut along the cutting road 9 of the display master 5, and finally a plurality of display panels 8 can be formed. Since the alignment mark 6 in this embodiment can be accurately aligned with the alignment mark of the mask, the relevant film layer of the light-emitting unit 4 can be more accurately evaporated at the corresponding position, thereby improving the display effect of the light-emitting unit 4. Since the light-emitting unit 4 is located in the display area AA of the display panel 8, the display effect of the finally formed display panel 8 can be improved.

[0079] For some possible implementations, see again Figure 5 The light-emitting unit 4 includes a first electrode 2 , a light-emitting functional layer 10 , and a second electrode 11 which are sequentially stacked in a direction away from the substrate 1 .

[0080] Among them, the first electrode 2 can be an anode, the second electrode 11 can be a cathode, and the light-emitting functional layer 10 includes a hole injection layer 101, a hole transport layer 102, a light-emitting layer 103, an electron transport layer 104 and an electron injection layer 105, which are stacked in sequence along the direction away from the substrate 1. The light-emitting layer 103 is located in the pixel opening 31. The light-emitting layer 103 may include a first light-emitting portion, a second light-emitting portion and a third light-emitting portion with different light-emitting colors and arranged at intervals. For example, the light-emitting color of the first light-emitting portion is red, the light-emitting color of the second light-emitting portion is green, and the light-emitting color of the third light-emitting portion is blue.

[0081] The hole injection layer 101, the hole transport layer 102, the electron transport layer 104 and the electron injection layer 105 extend from the pixel opening 31 to the side of the pixel defining layer 3 away from the substrate 1. After the mask and the display motherboard 5 are accurately aligned through the alignment mark 6 and the alignment mark, the hole injection layer 101, the hole transport layer 102, the light-emitting layer 103, the electron transport layer 104, the electron injection layer 105 and the second electrode 11 can be accurately evaporated through the mask.

[0082] Preferably, see Figure 4-Figure 7 The substrate 1 includes a transparent substrate 12 and a plurality of metal layers located on one side of the transparent substrate 12 and stacked in sequence in a direction away from the transparent substrate 12; the alignment mark 6 is in the same layer and material as the first electrode 2, and / or the alignment mark 6 is in the same layer and material as any one of the plurality of metal layers.

[0083] Optionally, the material of the first electrode 2 includes three layers of indium tin oxide, silver and indium tin oxide (ItoAgIto) which are stacked in sequence.

[0084] Optionally, the material of the metal layer includes three layers of titanium, aluminum and titanium (TiAlTi) or three layers of molybdenum, aluminum and molybdenum (MoAlMo) stacked in sequence.

[0085] When the alignment mark 6 and the first electrode 2 are in the same layer and material, the alignment mark 6 can be formed while the first electrode 2 is formed, so there is no need to set up a special process to form the alignment mark 6, thereby reducing the cost of forming the alignment mark 6.

[0086] When the alignment mark 6 is of the same layer and material as any one of the multiple metal layers, for example, the multiple metal layers include a first metal layer 14, a second metal layer 15, a third metal layer 16 and a fourth metal layer 17 stacked in sequence, and the alignment mark 6 is of the same layer and material as the fourth metal layer 17, then the alignment mark 6 can be formed while forming the fourth metal layer 17, thereby eliminating the need to set up a special process to form the alignment mark 6, thereby reducing the cost of forming the alignment mark 6.

[0087] Preferably, see again Figure 5 and Figure 7 The substrate 1 further includes a planarization layer 13 located between the transparent substrate 2 and the alignment mark 6 .

[0088] For example, the planarization layer 13 can be located on the side of the fourth metal layer 17 away from the substrate. Since the transparent substrate 2 and the planarization layer 13 are both transparent film layers, after the light passes through the transparent substrate 2 and the planarization layer 13, the color of the mask and the color of the alignment mark 6 can be more accurately compared, so that the mask and the display motherboard 5 can be positioned more accurately.

[0089] For some possible implementations, see again Figure 6 The light absorbing layer 7 covers the side of the alignment mark 6 away from the substrate 1 and covers the side wall of the alignment mark 6, that is, the light absorbing layer 7 covers the other surfaces of the alignment mark 6 except the side close to the substrate 1, so that the color difference between the alignment mark 6 on the display motherboard 5 and the alignment mark on the mask can be greater, thereby making the alignment between the alignment mark 6 and the alignment mark on the mask more accurate.

[0090] Preferably, along the thickness direction Z of the substrate 1, the thickness D of the light absorbing layer 7 is greater than or equal to 0.5 μm and less than or equal to 1.5 μm. For example, the thickness D may be 0.5 μm, 0.6 μm, 0.8 μm, 1 μm, 1.2 μm, 1.4 μm or 1.5 μm, etc. Reasonable setting of the thickness D can make the alignment between the alignment mark 6 and the alignment mark on the mask more accurate.

[0091] In some possible implementations, the color of the material of the light absorbing layer 7 includes black, and the color of the alignment mark 6 includes white; or, the color of the material of the light absorbing layer 7 includes white, and the color of the alignment mark 6 includes black.

[0092] When the color of the material of the light absorbing layer 7 is black, the color of the alignment mark 6 is white; when the color of the material of the light absorbing layer 7 is white, the color of the alignment mark 6 is black. In this way, the color difference between the light absorbing layer 7 and the alignment mark 6 is greater, so that the color difference between the alignment mark of the mask on the evaporation machine obtained by the camera and the alignment mark 6 on the display master 5 can be greater, so that the camera can more accurately identify the alignment mark 6 on the display master 5 and the alignment mark on the mask.

[0093] In some possible implementations, the material of the light absorbing layer 7 includes metal materials, inorganic materials or organic materials.

[0094] The color of the metal material, inorganic material or organic material is black, that is, in this embodiment, the color of the light absorbing layer 7 is preferably black, and the color of the alignment mark 6 is white. Specifically, the material of the light absorbing layer 7 includes at least one of metal chromium, metal manganese or metal chromium-manganese alloy.

[0095] For some possible implementations, see again Figure 4 The number of alignment marks 6 is multiple groups, and each group of alignment marks 6 includes a first alignment sub-mark 61 and a second alignment sub-mark 62 .

[0096] By using a plurality of groups of alignment marks 6 and the first alignment sub-marks 61 and the second alignment sub-marks 62 of each group of alignment marks 6, the alignment between the mask and the display master 5 can be made more precise.

[0097] Preferably, the orthographic projection of the first alignment sub-mark 61 on the substrate 1 is in the shape of a square, and the orthographic projection of the second alignment sub-mark 62 on the substrate 1 is in the shape of a cross.

[0098] Since it is easier to obtain the centers of the square and the cross, by setting the shape of the first alignment sub-mark 61 to a square and the shape of the second alignment sub-mark 62 to a cross, it is easier to obtain the centers of the first alignment sub-mark 61 and the second alignment sub-mark 62, thereby making the alignment between the mask plate and the display master 5 more precise.

[0099] For some possible implementations, see Figure 8 The present application also provides a method for preparing a display motherboard, the method comprising:

[0100] S10: providing a substrate 1.

[0101] S11 : forming a conductive layer and an alignment mark 6 on one side of the substrate 1 .

[0102] See also Fig. 9 The conductive layer may include any one of the multiple metal layers in the substrate, and may also include a first electrode. When the alignment mark 6 is in the same layer and material as the first electrode 2, the alignment mark 6 may be formed while the first electrode 2 is formed; when the alignment mark 6 is in the same layer and material as any one of the multiple metal layers, the alignment mark 6 may be formed while the metal layer is formed, thereby eliminating the need to set up a special process to form the alignment mark 6, thereby reducing the cost of forming the alignment mark 6.

[0103] The display motherboard includes a functional area GN and a border area BK, the first electrode 2 is located in the functional area GN, the alignment mark 6 is located in the border area BK, the functional area GN has a display function, and the border area BK does not have a display function. Setting the alignment mark 6 in the border area BK can prevent the alignment mark 6 from affecting the display of the functional area GN, thereby improving the display effect of the display motherboard 5.

[0104] S12 : forming a light absorbing layer 7 covering the alignment mark 6 on the side of the alignment mark 6 away from the substrate 1 .

[0105] See also Fig.10 A light absorption layer 7 is formed on the side of the alignment mark 6 away from the substrate 1 . The light absorption layer 7 is only located in the frame area BK, and the light absorption layer 7 does not affect the display of the functional area GN.

[0106] S13 : forming a pixel defining layer 3 on a side of the conductive layer away from the substrate 1 , wherein the pixel defining layer 3 defines a pixel opening 31 .

[0107] See also Fig.11A pixel defining layer 3 is formed on a side of the first electrode 2 away from the substrate 1 , and a pixel opening 31 of the pixel defining layer 3 exposes a portion of the first electrode 2 .

[0108] S14: Align the alignment mark on the mask plate with the alignment mark 6 on the display master 5.

[0109] Since the color of the light-absorbing layer 7 is significantly different from the color of the alignment mark 6, the color of the alignment mark 6 obtained by the camera and the alignment mark on the mask are significantly different. The camera can more accurately determine the relative position between the alignment mark 6 on the display master 5 and the alignment mark on the mask, thereby making the alignment between the alignment mark 6 on the display master 5 and the alignment mark on the mask more accurate.

[0110] S15: sequentially forming the light-emitting functional layer 10 and the second electrode 11 layer of the light-emitting unit 4 in the pixel opening 31 through a mask plate, and at least part of the film layer in the light-emitting functional layer 10 and the second electrode 11 layer extend to the side of the pixel defining layer 3 away from the substrate 1 .

[0111] See also Figure 4 and Fig.12 Since the alignment between the mask and the display master 5 is more accurate, the light-emitting functional layer 10 and the second electrode 11 of the display master 5 can be accurately evaporated at corresponding positions by the evaporation machine, and finally the quality of the display master 5 can be improved through the above direction.

[0112] For some possible implementations, see Fig.13 The present application also provides a method for preparing a display panel 8, the method comprising:

[0113] S20: providing a substrate 1.

[0114] S21 : forming a first electrode 2 and an alignment mark 6 on one side of the substrate 1 .

[0115] Please see again Fig. 9 The conductive layer may include multiple metal layers in the substrate and may also include a first electrode. When the alignment mark 6 is in the same layer and material as the first electrode 2, the alignment mark 6 can be formed while the first electrode 2 is formed; when the alignment mark 6 is in the same layer and material as any one of the multiple metal layers, the alignment mark 6 can be formed while the metal layer is formed. Thus, there is no need to set up a special process to form the alignment mark 6, thereby reducing the cost of forming the alignment mark 6.

[0116] The display motherboard includes a functional area GN and a border area BK, the first electrode 2 is located in the functional area GN, the alignment mark 6 is located in the border area BK, the functional area GN has a display function, and the border area BK does not have a display function. Setting the alignment mark 6 in the border area BK can prevent the alignment mark 6 from affecting the display of the functional area GN, thereby improving the display effect of the display motherboard 5.

[0117] S22 : forming a light absorbing layer 7 covering the alignment mark 6 on the side of the alignment mark 6 away from the substrate 1 .

[0118] Please see again Fig.10 A light absorption layer 7 is formed on the side of the alignment mark 6 away from the substrate 1 . The light absorption layer 7 is only located in the frame area BK, and the light absorption layer 7 does not affect the display of the functional area GN.

[0119] S23 : forming a pixel defining layer 3 on a side of the conductive layer away from the substrate 1 , wherein the pixel defining layer 3 defines a pixel opening 31 .

[0120] Please see again Fig.11 A pixel defining layer 3 is formed on a side of the first electrode 2 away from the substrate 1 , and a pixel opening 31 of the pixel defining layer 3 exposes a portion of the first electrode 2 .

[0121] S24: Align the alignment mark on the mask plate with the alignment mark 6 on the display master 5.

[0122] Since the color of the light-absorbing layer 7 is significantly different from the color of the alignment mark 6, the color of the alignment mark 6 obtained by the camera and the alignment mark on the mask are significantly different. The camera can more accurately determine the relative position between the alignment mark 6 on the display master 5 and the alignment mark on the mask, thereby making the alignment between the alignment mark 6 on the display master 5 and the alignment mark on the mask more accurate.

[0123] S25: A light-emitting functional layer 10 and a second electrode 11 layer of the light-emitting unit 4 are sequentially formed in the pixel opening 31 through a mask plate to form a display motherboard 5, wherein the display motherboard 5 includes a functional area GN and a border area BK surrounding at least part of the functional area GN, and the alignment mark 6 is located in the border area BK. The display motherboard includes a plurality of display panels 8 arranged at intervals, and the plurality of display panels 8 are located in the functional area GN. The display panel 8 includes a display area AA and a non-display area AB surrounding at least part of the display area AA, and a cutting path 9 is defined between the non-display areas AB of two adjacent display panels 8, and the light-emitting unit 4 is located in the display area AA.

[0124] Please see again Figure 4 and Fig.12Since the alignment between the mask and the display master 5 is more accurate, the light-emitting functional layer 10 and the second electrode 11 of the display master 5 can be accurately evaporated at corresponding positions by an evaporation machine. Ultimately, the quality of the display master 5 can be improved by the above method.

[0125] S26 : cutting the display motherboard 5 along the cutting road 9 , and cutting off the frame area BK of the display motherboard 5 with the alignment mark 6 , so as to form a plurality of display panels 8 .

[0126] See also Figure 4 and Fig.14 The display motherboard 5 is cut along the cutting road 9 by a cutting device, and the border area BK of the display motherboard 5 is removed, so that a display panel 8 without the alignment mark 6 can be finally formed.

[0127] Since the above method can make the mask and the display motherboard 5 more accurately aligned, the light-emitting functional layer 10 and the second electrode 11 of the light-emitting unit 4 can be more accurately evaporated, thus improving the display effect of the display panel 8 finally formed.

[0128] In some possible implementations, the present application further provides an electronic device, which includes the display motherboard in the present application, or includes the display motherboard prepared by the method for preparing the display motherboard in the present application, or includes the display panel 8 prepared by the method for preparing the display panel 8 in the present application. The electronic device may include a device with image processing capabilities, such as a server, a personal computer, a laptop computer, a mobile phone, a tablet computer, a wearable device, a vehicle-mounted display device, etc. Since the electronic device includes the display panel 8 or the display motherboard 5 in the present application, the display effect of the electronic device is better.

[0129] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0130] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A display motherboard, characterized in that: The display motherboard comprises: substrate; A pixel defining layer, located on one side of the substrate, wherein the pixel defining layer defines a pixel opening; a light emitting unit, at least a portion of which is located within the pixel opening; an alignment mark located in and / or on the substrate; The light absorbing layer is located on a side of the alignment mark away from the substrate, and the light absorbing layer covers at least a portion of the alignment mark.

2. The display motherboard according to claim 1, characterized in that: The light absorbing layer covers a side of the alignment mark away from the substrate and covers a side wall of the alignment mark; Preferably, along the thickness direction of the substrate, the thickness of the light absorption layer is greater than or equal to 0.5 μm and less than or equal to 1.5 μm.

3. The display motherboard according to claim 1, characterized in that: The color of the material of the light absorbing layer includes black, and the color of the alignment mark includes white; or the color of the material of the light absorbing layer includes white, and the color of the alignment mark includes black.

4. The display motherboard according to claim 1, characterized in that: The material of the light absorbing layer includes metal material, inorganic material or organic material; Preferably, the material of the light absorbing layer includes at least one of metal chromium, metal manganese or metal chromium-manganese alloy; Preferably, the color of the metal material, inorganic material or organic material is black.

5. The display motherboard according to claim 1, characterized in that: The light-emitting unit comprises a first electrode, a light-emitting functional layer, and a second electrode which are sequentially stacked in a direction away from the substrate, and the substrate comprises a substrate and a plurality of metal layers which are located on one side of the substrate and sequentially stacked in a direction away from the substrate; the alignment mark is in the same layer and material as the first electrode, and / or the alignment mark is in the same layer and material as any one of the plurality of metal layers; Preferably, the material of the first electrode includes three layers of indium tin oxide, silver and indium tin oxide stacked in sequence; Preferably, the material of the metal layer includes three layers of titanium, aluminum and titanium or three layers of molybdenum, aluminum and molybdenum stacked in sequence; Preferably, the material of the substrate is a transparent material; Preferably, the substrate further comprises a planarization layer located between the substrate and the alignment mark.

6. The display motherboard according to claim 1, characterized in that: The number of the alignment marks is multiple groups, and each group of the alignment marks includes a first alignment sub-mark and a second alignment sub-mark; Preferably, the orthographic projection of the first pair of sub-marks on the substrate is a square; Preferably, the orthographic projection of the second alignment sub-mark on the substrate is in the shape of a cross.

7. The display motherboard according to any one of claims 1 to 6, characterized in that: The display motherboard includes a functional area and a frame area surrounding at least a portion of the functional area, and the alignment mark is located in the frame area; Preferably, the display motherboard comprises a plurality of display panels arranged at intervals, the plurality of display panels are located in the functional area, the display panel comprises a display area and a non-display area surrounding at least a portion of the display area, a cutting path is defined between the non-display areas of two adjacent display panels, and the light emitting unit is located in the display area; Preferably, the light absorbing layer is located in the border area.

8. A method for preparing a display motherboard, characterized in that: The method comprises: providing a substrate; forming a conductive layer and an alignment mark on one side of the substrate; forming a light absorbing layer covering the alignment mark on a side of the alignment mark away from the substrate; forming a pixel defining layer on a side of the conductive layer away from the substrate, wherein the pixel defining layer defines a pixel opening; Aligning the alignment mark on the mask plate with the alignment mark on the display master; The light-emitting functional layer and the second electrode layer of the light-emitting unit are sequentially formed in the pixel opening through the mask plate, and at least part of the film layer in the light-emitting functional layer and the second electrode layer extend to the side of the pixel defining layer away from the substrate.

9. A method for preparing a display panel, characterized in that: The method comprises: providing a substrate; forming a conductive layer and an alignment mark on one side of the substrate; forming a light absorbing layer covering the alignment mark on a side of the alignment mark away from the substrate; forming a pixel defining layer on a side of the conductive layer away from the substrate, wherein the pixel defining layer defines a pixel opening; Aligning the alignment mark on the mask plate with the alignment mark on the display master; The light-emitting functional layer and the second electrode layer of the light-emitting unit are sequentially formed in the pixel opening by the mask plate to form a display motherboard, wherein the display motherboard includes a functional area and a frame area surrounding at least part of the functional area, the alignment mark is located in the frame area, the display motherboard includes a plurality of display panels arranged at intervals, the plurality of display panels are located in the functional area, the display panel includes a display area and a non-display area surrounding at least part of the display area, a cutting path is defined between the non-display areas of two adjacent display panels, and the light-emitting unit is located in the display area; The display motherboard is cut along the cutting path, and the frame area of ​​the display motherboard with the alignment mark is cut off to form a plurality of display panels.

10. An electronic device, characterized in that: The electronic device includes the display motherboard described in any one of claims 1 to 7, or includes the display motherboard prepared by the display motherboard preparation method described in claim 8, or includes the display panel prepared by the display panel preparation method described in claim 9.

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