Manufacturing method of display panel, mask and display panel

Abstract

The invention discloses a manufacturing method of a display panel, a mask plate and the display panel. The manufacturing method of the display panel comprises the following steps: providing a substrate; controlling an evaporation source to emit luminescent material particles towards the substrate; when the luminescent material particles pass through the holes of the mask, controlling the directivity of the evaporation beam of the luminescent material particles through the mask, and improving the uniformity of the evaporation beam of the luminescent material particles with at least one hole; forming a plurality of light emitting layers on the substrate; wherein the mask plate is provided with a plurality of open pores, and the distances between at least two open pores and the evaporation source are not equal. The directivity of the evaporation beam is restrained by using the mask, so that the uniformity of the evaporation beam of the light-emitting material particles emitted from the holes of the mask is enhanced, and the film uniformity of the formed light-emitting layer is improved.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a display panel, a method for manufacturing the same, a photomask, and the display panel. Background Technology

[0002] In OLED (Organic Light-Emitting Diode) devices, the organic light-emitting unit (OLED) is the core component, which needs to be formed through a vapor deposition process. Different colored OLEDs require separate vapor deposition steps due to differences in materials, formation location, and size. Generally, the luminescent material of the OLED needs to be deposited using a photomask. The photomask is placed close to the substrate, and channels are created on the photomask to allow the luminescent material to pass through. Areas on the photomask without channels prevent the luminescent material from passing through, thus forming a patterned luminescent material.

[0003] In particular, because the directionality of the vapor-deposited material passing through the openings at different positions on the photomask is uncontrollable, the path traveled by the vapor-deposited material in the openings at different positions from the evaporation source is different, which actually leads to poor uniformity of the light-emitting layer formed on the substrate. Summary of the Invention

[0004] The purpose of this application is to provide a method for manufacturing a display panel, a mask, and a display panel. By using a mask to constrain the directionality of the evaporation beam, the uniformity of the evaporation beam of the light-emitting material particles emitted from the openings of the mask is enhanced, thereby improving the uniformity of the film layer of the formed light-emitting layer.

[0005] This application discloses a method for manufacturing a display panel, characterized by comprising the following steps: Provide a substrate; The evaporation source is controlled to emit luminescent material particles toward the substrate. When the luminescent material particles pass through the openings of the mask, the directionality of the evaporation beam of the luminescent material particles is controlled by the mask, thereby improving the uniformity of the evaporation beam of the luminescent material particles at least one opening. Multiple light-emitting layers are formed on the substrate. The mask has multiple openings, and at least two of the openings are not equidistant from the evaporation source.

[0006] Optionally, the mask is provided with multiple deformation structures, which are disposed within the openings; the step of controlling the directionality of the evaporation beam of the luminescent material particles through the mask when the luminescent material particles pass through the openings of the mask, thereby improving the uniformity of the evaporation beam of the luminescent material particles in at least one opening, includes: The deformation of at least one of the openings is controlled to reduce the radial width of the opening at the location of the deformation structure, thereby forming a slit. When the luminescent material particles pass through the opening in the mask, the uniformity of the evaporation beam of the luminescent material particles is improved after passing through the slit.

[0007] Optionally, the greater the distance between the opening and the evaporation source, the greater the radial width of the slit within the opening; or the greater the distance between the opening and the evaporation source, the farther the slit within the opening is from the evaporation source.

[0008] Optionally, in the direction of the evaporation source toward the substrate, the radial width of the slit gradually decreases and then gradually increases; the maximum width of the slit is equal to the width of the opening; wherein the deformation structure is formed of a piezoelectric material, and the deformation structure deforms under the control of an electrical signal to narrow the radial width of the opening to form a slit.

[0009] Optionally, the step of providing a substrate includes: Provide a substrate; A patterned bottom electrode is formed on the substrate. A pixel definition layer is formed on the bottom electrode, the pixel definition layer having multiple opening regions, and the bottom electrode being exposed from the opening regions; wherein, between two bottom electrodes, the width of the pixel definition layer gradually increases toward the side away from the substrate. The step of controlling the evaporation source to emit luminescent material particles toward the substrate includes: Provide a mask; Align the multiple openings on the mask with the multiple opening areas on the substrate one by one; The evaporation source is controlled to emit luminescent material particles toward the substrate. The step of forming multiple light-emitting layers on the substrate includes: At each of the said opening regions, a light-emitting layer is formed on the bottom electrode; wherein the multiple light-emitting layers have the same thickness.

[0010] This application also discloses a photomask for the above-mentioned method of manufacturing a display panel. The photomask includes a photomask body, a plurality of openings disposed on the photomask body, and a plurality of deformation structures disposed within the plurality of openings. The deformation structures are used to deform under the control of an electrical signal, so that the radial width of the openings at the location of the deformation structures is narrowed to form a slit.

[0011] Optionally, the mask body includes a first mask and a second mask, with a gap between the first mask and the second mask; the first mask and the second mask are respectively provided with a plurality of mesh holes, and in a direction perpendicular to the first mask, the mesh holes of the first mask and the mesh holes of the second mask form an opening, the opening being used to allow light-emitting material particles to pass through; the deformation structure is disposed between the first mask and the second mask, and is disposed within the opening; the mask body includes a first central region, the first central region being configured to correspond with the evaporation source during the light-emitting layer process; the greater the distance between the opening and the first central region, the smaller the radial width of the slit within the opening; or the greater the distance between the opening and the first central region, the farther the slit within the opening is from the first mask.

[0012] Optionally, in the direction of the evaporation source toward the substrate, the radial width of the slit gradually decreases and then gradually increases; the maximum width of the slit is equal to the width of the opening; wherein the deformation structure is formed of a piezoelectric material, and the deformation structure deforms under the control of an electrical signal to narrow the radial width of the opening to form a slit.

[0013] This application also discloses a display panel formed by the above-described display panel manufacturing method. The display panel includes a substrate, a pixel definition layer disposed on the substrate, and a plurality of light-emitting units. The pixel definition layer has a plurality of opening regions, and the plurality of light-emitting units are respectively disposed in the plurality of opening regions. Adjacent light-emitting units are separated by the pixel definition layer. The light-emitting unit includes a bottom electrode, a light-emitting layer, and a top electrode. The light-emitting layer is disposed between the bottom electrode and the top electrode, and the plurality of light-emitting layers have the same thickness.

[0014] Optionally, between the two bottom electrodes, the width of the pixel definition layer gradually increases toward the side away from the substrate; wherein, the substrate includes a second central region, which is configured to correspond to the evaporation source during the light-emitting layer fabrication process; the further away from the opening region from the second central region, the smaller the radial width of the opening region, and the larger the maximum width of the adjacent pixel definition layer.

[0015] In this application, the directionality of the evaporation beam of luminescent material particles is controlled using a photomask. This allows the luminescent material particles to pass through the openings in the photomask, constraining the directionality of the evaporation beam under the mask's control. This enhances the uniformity of the evaporation beam exiting the photomask, resulting in improved uniformity of the luminescent layer formed after passing through the mask. This enables directional control of the film thickness deposited at different locations. Furthermore, it ensures that the film thickness at different locations remains equal, thereby improving the uniformity of the film layer. Attached Figure Description

[0016] The accompanying drawings, which form part of the specification, are used to provide a further understanding of the embodiments of this application and illustrate the implementation methods of this application, together with the textual description, to explain the principles of this application. Obviously, the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any creative effort. In the drawings: Figure 1 This is a schematic diagram illustrating the steps of a method for manufacturing a display panel according to the first embodiment of this application; Figure 2 This is a schematic diagram illustrating the fabrication of the display panel according to the first embodiment of this application; Figure 3 This is a schematic diagram of the deformed structure of this application; Figure 4 This is a schematic diagram of the evaporation source and the mask in this application. Figure 5 This is a schematic diagram illustrating the manufacture of another display panel according to the first embodiment of this application; Figure 6 This is a schematic diagram of a method for manufacturing a display panel according to the second embodiment of this application; Figure 7 This is a schematic diagram of another method for manufacturing a display panel according to the second embodiment of this application; Figure 8 This is a top view of the photomask used in this application; Figure 9 This is a cross-sectional schematic diagram of the display panel of this application; Figure 10 This is a top view of the display panel of this application.

[0017] Among them, 100 is a display panel; 110 is a substrate; 111 is a pixel definition layer; 112 is a second central region; 113 is an opening region; 120 is a light-emitting unit; 121 is a bottom electrode; 122 is a light-emitting layer; 123 is a top electrode; 200 is a mask; 210 is a mask body; 211 is a first mask; 212 is a second mask; 213 is a first central region; 214 is a mesh; 220 is an opening; 221 is a slit; 230 is a deformation structure; and 300 is an evaporation source. Detailed Implementation

[0018] It should be understood that the terminology, specific structural and functional details used herein are merely for describing particular embodiments and are representative. However, this application may be implemented in many alternative forms and should not be construed as being limited to the embodiments set forth herein.

[0019] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating relative importance or implying the number of technical features indicated. Therefore, unless otherwise stated, a feature specified as "first" or "second" may explicitly or implicitly include one or more of that feature; "multiple" means two or more. Furthermore, terms such as "upper," "lower," "left," "right," "vertical," and "horizontal," indicating orientation or positional relationships, are based on the orientation or relative positional relationships shown in the accompanying drawings and are only for the purpose of simplifying the description of this application, not indicating that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting this application. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0020] The present application will now be described in detail with reference to the accompanying drawings and optional embodiments.

[0021] Figure 1 This is a schematic diagram illustrating the steps of a method for manufacturing a display panel according to the first embodiment of this application. Figure 2 This is a schematic diagram of the manufacturing process of the display panel according to the first embodiment of this application. See also: Figures 1 to 2 As shown, this application discloses a method for manufacturing a display panel, including the following steps: S10: Provides a substrate; S20: Control the evaporation source to emit luminescent material particles toward the substrate; S30: When the luminescent material particles pass through the opening of the mask, the directionality of the evaporation beam of the luminescent material particles is controlled by the mask to improve the uniformity of the evaporation beam of the luminescent material particles in at least one opening. S40: A plurality of light-emitting layers are formed on the substrate; The mask has multiple openings, and at least two of the openings are not equidistant from the evaporation source.

[0022] In this application, the directionality of the evaporation beam of luminescent material particles is controlled using a photomask. This allows the luminescent material particles to pass through the openings in the photomask, constraining the directionality of the evaporation beam under the mask's control. This enhances the uniformity of the evaporation beam exiting the photomask, resulting in improved uniformity of the luminescent layer formed after passing through the mask. This enables directional control of the film thickness deposited at different locations. Furthermore, it ensures that the film thickness at different locations remains equal, thereby improving the uniformity of the film layer.

[0023] Specifically, the evaporation process used in this application for the light-emitting layer is vacuum evaporation. In a vacuum environment, the light-emitting material is heated, vaporized, and deposited onto a substrate to obtain a thin film material as the light-emitting layer. Generally, the quality of the light-emitting material determines the performance of the display panel, while the quality of the evaporation source determines the effectiveness of the light-emitting layer evaporation. Both play a decisive role in the yield, quality, and lifespan of the display panel.

[0024] Currently, evaporation sources can be broadly classified into two types: point evaporation sources and surface evaporation sources. Generally, evaporation sources that are relatively far from the substrate and have a small size can be considered point evaporation sources. Surface evaporation sources consist of a small hole with a very small diameter at the top of a high-temperature crucible. Inside the crucible, the vapor pressure of the luminescent material is approximately equal to its equilibrium vapor pressure, while outside the crucible, a high degree of vacuum is maintained. Due to its smaller effective evaporation area, surface evaporation sources have a lower evaporation rate, but their evaporation beam has better directionality.

[0025] Specifically, on the photomask, at least one opening location is provided with a slit, the radial width of which is smaller than the radial width of the opening.

[0026] In this application, the width within the opening is reduced by using a mask to control the directionality of the evaporation beam of the luminescent material particles. This allows the luminescent material particles to exit onto the substrate through a narrower channel, such as a slit, when passing through the opening. By setting a slit at the opening position of the mask, the directionality of the evaporation beam of the luminescent material particles is constrained, thereby improving the uniformity of the evaporation beam of the luminescent material particles.

[0027] Figure 3 This is a schematic diagram of the deformed structure of this application, see [link / reference]. Figure 3 As shown, specifically, the photomask is provided with multiple deformation structures, which are disposed within the opening; step S30 includes: S301: Control the deformation of at least one of the deformation structures in the opening so that the radial width of the opening at the location of the deformation structure is narrowed to form a slit; S302: When the luminescent material particles pass through the opening of the mask, the uniformity of the evaporation beam of the luminescent material particles is improved after passing through the slit.

[0028] In this embodiment, a deformation structure is used at the opening location of the photomask to create slits of varying widths. This deformation structure at the opening reduces the radial width of the opening, constraining the evaporation gas flow from the luminescent material particles. This results in better uniformity of the luminescent layer formed after the particles pass through the slit. In other words, creating a slit at the opening is equivalent to creating a surface evaporation source at that location. Because the photomask is close to the substrate, each opening has its own surface evaporation source, resulting in better directionality of the evaporation beam and improved uniformity of the luminescent layer formed at multiple locations on the substrate. More importantly, this solves the problem of the current limitations on the width of openings in photomasks due to process constraints.

[0029] In one specific embodiment, step S10 further includes: S101: A substrate is provided; the substrate can be a flexible substrate or a non-flexible substrate. Before the fabrication process of the light-emitting unit, a pixel driving layer is generally formed on the substrate. This pixel driving layer typically has multiple thin-film transistors and various signal lines, thereby forming a pixel driving circuit that drives each light-emitting unit to emit light. After the pixel driving layer fabrication process is completed, the light-emitting unit fabrication process begins.

[0030] S102: Forming a patterned bottom electrode on a substrate; S103: A pixel definition layer is formed on the bottom electrode, the pixel definition layer is provided with a plurality of opening areas, and the bottom electrode is exposed from the opening areas; The light-emitting unit typically includes a bottom electrode, a light-emitting layer, and a top electrode. The light-emitting layer is located between the bottom and top electrodes. By applying different voltage signals to the bottom electrode, different brightness levels of the light-emitting layer are achieved. This bottom electrode is also typically connected to a pixel driving circuit located in the pixel driving layer, acquiring corresponding display signals via data lines.

[0031] It is understood that the main steps involved in the manufacturing method of the display panel in this application are the fabrication of the light-emitting layer. After the light-emitting layer is formed, the process also includes forming a top electrode, thereby forming multiple light-emitting units on the substrate. After completing the fabrication of the light-emitting units, a packaging process is often required to form the display panel. Other processes have not been specifically improved in this application and will not be described in detail here.

[0032] Step S20 includes: S201: Provides a photomask; S202: Align the multiple openings on the mask with the multiple opening areas on the substrate one by one; S203: Control the evaporation source to emit luminescent material particles toward the substrate; The photomask in this embodiment is generally a metal photomask, also known as a fine metal photomask. By setting multiple openings on the photomask, the vapor-deposited material emitted from the evaporation source can pass through the openings but cannot pass through the non-opening areas, thereby forming a patterned film layer. For example, the luminescent material particles in this embodiment, after passing through the openings, directly enter the opening area and form a luminescent layer on the bottom electrode. Moreover, the luminescent layer in each opening area is independently set and is a patterned luminescent layer.

[0033] Figure 4 This is a schematic diagram of the evaporation source and mask deposition in this application. See [link / reference]. Figure 4 As shown, the distance from the evaporation source to the mask is TS (Target-Source Distance), which is typically between 400nm and 800nm. When the TS distance is small, the utilization rate of the luminescent material particles is high, resulting in a lower pixel PPI, but the film uniformity is poor, and the SD (Shadow Distance) is large. When the TS distance is large, the film uniformity changes, the SD decreases, but the material utilization rate is lower, and the PPI is larger. Different distances and positions from the same evaporation source to various openings will result in variations in the thickness of the deposited film, which can severely affect the luminescence lifetime and the lifespan of the display panel.

[0034] When performing vapor deposition on large panels, multiple evaporation sources are typically used simultaneously, each corresponding to a specific area. These sources may or may not overlap. Large panels are usually cut into multiple display panels. Because the distances from the evaporation sources to the various openings on the mask are not equidistant, the thickness of the light-emitting layer formed at different opening locations is uneven. Specifically, at least two of the openings are unequal in distance from the evaporation source. When multiple evaporation sources are present, taking any single evaporation source as an example, at least two of the openings are unequal in distance from that source. The relative deposition thickness is related to the size of the substrate and the distance between the substrate and the evaporation source. As the ratio of the substrate size to the distance between the substrate and the evaporation source increases, the relative deposition thickness gradually decreases. It is worth noting that when different evaporation sources simultaneously provide light-emitting material particles to the same opening, uneven light-emitting layer thickness at different locations often exists. This application can also solve the problem of uneven light-emitting layer thickness that may occur in this situation.

[0035] Figure 5 This is a schematic diagram illustrating the fabrication of another display panel according to the first embodiment of this application. See also... Figure 5 As shown, in one embodiment, the difference in film thickness caused by the different distances between the opening and the evaporation source can be balanced by adjusting the width of the slit at different opening positions.

[0036] Specifically, the greater the distance between the opening and the evaporation source, the greater the radial width of the slit within the opening.

[0037] In this embodiment, considering that the greater the distance between the opening and the evaporation source, the farther the luminescent material particles are from the evaporation source to the opening, the lower the corresponding gas flow concentration or the number of luminescent material particles, resulting in a thinner film thickness of the luminescent layer subsequently formed on the substrate corresponding to the opening. In this solution, by making the radial width of the slit with a larger distance greater, as many luminescent material particles as possible can pass through the slit, thereby increasing the number of luminescent material particles at the opening location, and thus thickening the film thickness of the luminescent layer at that location.

[0038] The width of the slit can be less than or equal to half the width of the opening, and greater than or equal to one-third the width of the opening. In this case, the width of the slit is related to the permeability of the luminescent material particles; when the width is small, the permeability of the luminescent material particles is relatively weakened. However, the smaller the width, the better the collimation of the luminescent material particles. In this embodiment, the required width for different types of display panels can be tested by limiting different luminescent materials and different types of display panels. Taking the emission direction of the luminescent material particles perpendicular to the mask as 0 degrees, the proportion of luminescent material particles passing through the slit with an emission direction within the range of 0 degrees to 30 degrees exceeds 80%.

[0039] Figure 6 This is a schematic diagram illustrating a method for manufacturing a display panel according to the second embodiment of this application. See also... Figure 6 As shown, in controlling the slits, it is not necessary to use different voltage signals to make the slits have different widths, such as W1 and W2 having different widths. In this embodiment, multiple deformable structures can be controlled by the same electrical signal to make them deform to the same width.

[0040] Specifically, the greater the distance between the opening and the evaporation source, the farther the slit inside the opening is from the evaporation source.

[0041] In this embodiment, the difference in film thickness caused by the different distances between the slits at different opening positions and the substrate, mask, or evaporation source can be balanced by adjusting the relative distances between the slits and the evaporation source, such as different lengths for h2 and h1. The substrate is generally parallel to the mask, and the evaporation source emits luminescent material particles perpendicularly towards both the mask and the substrate. Generally, the opening closest to the evaporation source has a line connecting the opening and the evaporation source perpendicular to the substrate or mask. Because this opening is closest to the evaporation source, the film thickness deposited per unit time is the greatest. Therefore, in practical design, the slits can be positioned as far away from the evaporation source as possible, resulting in different distances between the slits and the substrate at different opening positions. By changing the distance between the slits and the substrate, the difference in film thickness caused by the different opening distances from the evaporation source can be balanced.

[0042] In one specific embodiment, the radial width of the slit gradually decreases and then gradually increases in the direction from the evaporation source to the substrate. The slit can be moved as close to the substrate as possible, such that the maximum width of the slit facing the evaporation source is greater than the maximum width of the slit facing the evaporation source, resulting in an hourglass shape within the opening. The overall length of the opening is between 200 nm and 300 nm, ensuring that the emission direction of the luminescent material particles passing through the slit is as perpendicular as possible to the photomask. Furthermore, by adjusting the degree of deformation of the deformable structure, the minimum width of the slit can be less than or equal to half the width of the opening and greater than or equal to one-third of the width of the opening. This creates an evaporation port similar to an evaporation source at each opening, effectively forming multiple evaporation sources at multiple openings. Each equivalent evaporation source corresponds to only one opening area of ​​the luminescent layer, thereby improving the coating quality of the luminescent layer.

[0043] It is understood that the position and degree of deformation of the deformable structure, i.e., the two embodiments described above, can be used in combination, and the combined effect is better. The position and degree of deformation of the deformable structure can be adjusted according to the actual situation. In actual testing, by changing the position and degree of deformation of the deformable structure at different locations, the parameters of the corresponding light-emitting layer film can be adjusted to achieve a more uniform result.

[0044] Specifically, the steps in S40 include: S401: At each of the said opening regions, a light-emitting layer is formed on the bottom electrode; wherein the multiple light-emitting layers have the same thickness.

[0045] In this embodiment, taking a display panel with three primary colors as an example, a pixel generally has three sub-pixels, composed of red, green, and blue light-emitting units, respectively. Each color of light-emitting unit corresponds to a sub-pixel of a specific color, such as a red sub-pixel, a green sub-pixel, and a blue sub-pixel. The difference in the manufacturing process between different colored light-emitting units lies in the materials used in the light-emitting layer. For example, a red light-emitting unit generally requires a red light-emitting material to form the light-emitting layer to emit red light. Similarly, a green light-emitting unit uses a green light-emitting material to form the light-emitting layer, and a blue light-emitting unit uses a blue light-emitting material. In this embodiment, the manufacturing process of all light-emitting layers can be completed through three light-emitting layer processes. After completing the light-emitting layer process for all opening areas, a top electrode is formed on the light-emitting layer. This top electrode is continuously arranged in different opening areas, so that the top electrodes of light-emitting units at different positions have the same voltage.

[0046] In one embodiment, the deformable structure is configured to deform under electrical signal control, causing the radial width of the opening at the location of the deformable structure to narrow, thereby forming a slit. For example, the deformable structure is formed of a piezoelectric material, and the deformation under electrical signal control causes the radial width of the opening to narrow, forming a slit.

[0047] Taking piezoelectric ceramics as an example, the mechanism of the piezoelectric effect is as follows: Piezoelectric crystals have low symmetry. When deformed under external force, the relative displacement of positive and negative ions in the unit cell causes the centers of positive and negative charges to no longer coincide, leading to macroscopic polarization of the crystal. The surface charge density of the crystal is equal to the projection of the polarization intensity onto the surface. Therefore, when a piezoelectric material deforms under pressure, opposite charges will appear on its two ends. Conversely, when a piezoelectric material is polarized in an electric field, the position of the charges will cause deformation of the material. In this embodiment, the deformation of the piezoelectric material under the action of an electric field is mainly utilized.

[0048] Specifically, before deformation occurs, the deformable structure may slightly protrude from the side of the opening or be aligned with the side of the opening. After deformation occurs, in the direction from the evaporation source to the substrate, the radial width of the slit first gradually decreases and then gradually increases; the maximum width of the slit is equal to the width of the opening, and the minimum width of the slit is the same as described above regarding the slit width. In other words, the minimum width of the slit differs for openings at different locations, while the maximum width may be equal or unequal.

[0049] Figure 7 This is a schematic diagram illustrating another method for manufacturing a display panel according to the second embodiment of this application. See also... Figure 7 As shown, based on the above embodiments, this embodiment further improves the pixel definition layer. Specifically, in step S103, through an etching process, the side of the pixel definition layer gradually extends towards the opening region along the extension direction from the substrate towards the pixel definition layer. In other words, between the two bottom electrodes, the width of the pixel definition layer gradually increases towards the side away from the substrate.

[0050] In this embodiment, by setting a narrow opening in the pixel definition layer, luminescent material particles that do not meet the expected emission angle after passing through the slit are filtered by the narrow opening of the pixel definition layer, making the luminescent material particles in the actual film formation more controllable. Figure 7 The widths of a1 and a2 are different, so that the width of the opening area is different to adapt to the slit design mentioned above.

[0051] Figure 8 This is a top view of the photomask used in this application; see [link / reference]. Figures 2 to 8 As shown, this application also discloses a mask 200 used in the above-described method for manufacturing a display panel. Specifically, the mask 200 includes a mask body 210, a plurality of openings 220 disposed on the mask body 210, and a plurality of deformation structures 230 disposed within the plurality of openings 220; the deformation structures 230 are configured to deform under the control of an electrical signal, so that the radial width of the openings 220 at the location of the deformation structure 230 narrows to form a slit 221.

[0052] In one embodiment, the mask body 210 includes a first mask 211 and a second mask 212, with a gap between the first mask 211 and the second mask 212. The first mask 211 and the second mask 212 are respectively provided with a plurality of mesh openings 214. In a direction perpendicular to the first mask 211, the mesh openings 214 of the first mask 211 and the mesh openings 214 of the second mask 212 form an opening 220, which allows luminescent material particles to pass through. The deformation structure 230 is disposed between the first mask 211 and the second mask 212, and is disposed within the opening 220.

[0053] In this embodiment, by setting the mask body 210 in a split structure, it is easier to set the deformation structure 230, avoiding the difficulty of setting the deformation structure 230 in the channel of the opening 220. By sandwiching multiple deformation structures 230 between the first mask 211 and the second mask 212, the deformation structure 230 does not need to be completely located inside the opening 220. Instead, the deformation structure 230 forms part of the sidewall of the opening 220. By controlling the deformation of the deformation structure 230, the width of the channel inside the opening 220 is reduced to form a slit 221. Moreover, it is easier to implement control routing of the deformation structure 230.

[0054] Of course, the depth of the aperture 220 is related to the thickness of the mask 200. When the mask 200 is thin, the depth of the aperture 220 is also limited, which limits the size design of the deformable structure 230. In this case, the thickness of the mask 200 can be increased to improve the depth of the aperture 220.

[0055] In one embodiment, the mask body 210 includes a first central region 213, which is configured to correspond with the evaporation source 300 during the light-emitting layer fabrication process. The greater the distance between the opening 220 and the first central region 213, the smaller the radial width of the slit 221 within the opening 220; or the greater the distance between the opening 220 and the first central region 213, the farther the slit 221 within the opening 220 is from the first mask 211. The mask 200 can be individually designed to accommodate different types of light-emitting layers, making it suitable for different types of display panels.

[0056] In one embodiment, in the direction of the evaporation source 300 toward the substrate, the radial width of the slit 221 gradually decreases and then gradually increases; the maximum width of the slit 221 is equal to the width of the opening 220; wherein, the deformable structure 230 is formed of a piezoelectric material, and the deformable structure 230 deforms under the control of an electrical signal to narrow the radial width of the opening 220 to form the slit 221.

[0057] Figure 9 This is a cross-sectional schematic diagram of the display panel of this application. Figure 10 This is a top view of the display panel 100 of this application, see below. Figures 2 to 10 As shown, this application also discloses a display panel 100, which can be formed using the manufacturing method of the display panel 100 in any of the above embodiments.

[0058] The display panel 100 includes a substrate 110, a pixel definition layer 111 disposed on the substrate 110, and a plurality of light-emitting units 120. The pixel definition layer 111 is provided with a plurality of opening areas 113, and the plurality of light-emitting units 120 are respectively disposed in the plurality of opening areas 113. Two adjacent light-emitting units 120 are separated by the pixel definition layer 111. The light-emitting unit 120 includes a bottom electrode 121, a light-emitting layer 122, and a top electrode 123. The light-emitting layer 122 is disposed between the bottom electrode 121 and the top electrode 123, and the plurality of light-emitting layers 122 have the same thickness.

[0059] The display panel 100 in this embodiment is formed by the above-described method for manufacturing the display panel 100. By using a mask to control the directionality of the evaporation beam of the light-emitting material particles, the width within the opening 220 is reduced. This allows the light-emitting material particles to exit onto the substrate 110 through a narrower channel, such as a slit, when passing through the opening 220. By setting a slit at the opening 220 of the mask, the directionality of the evaporation beam of the light-emitting material particles is constrained, thereby improving the uniformity of the evaporation beam of the light-emitting material particles. The thickness of the light-emitting layer 122 within the multiple opening regions 113 formed is more uniform.

[0060] In one embodiment, the width of the pixel defining layer 111 between the two bottom electrodes 121 gradually increases towards the side away from the substrate 110. In this embodiment, by providing a narrow opening in the pixel defining layer 111, light-emitting material particles that do not meet the expected emission angle after passing through the slit are filtered by the narrow opening of the pixel defining layer 111, making the actual light-emitting material particles in the film more controllable. Moreover, when the top electrode 123 is subsequently formed, the top electrode 123 will not be affected by the pixel defining layer 111.

[0061] The substrate 110 includes a second central region 112, which is configured to correspond to the evaporation source during the fabrication of the light-emitting layer 122. The further away from the second central region 112 the opening region 113 is, the smaller its radial width and the larger the maximum width of the adjacent pixel definition layer 111. In this embodiment, the opening widths of different opening regions 113 are reasonably set by adjusting the width of the pixel definition layer 111 on the side farther from the substrate 110, thereby limiting the area of ​​the corresponding light-emitting unit 120. Of course, the width design of the opening region 113 needs to conform to the actual sub-pixel design.

[0062] It should be noted that the inventive concept of this application can form many embodiments, but due to the limited space of the application documents, they cannot all be listed. Therefore, without conflict, the embodiments described above or the technical features can be arbitrarily combined to form new embodiments. After the embodiments or technical features are combined, the original technical effect will be enhanced.

[0063] The above description, in conjunction with specific optional embodiments, provides a further detailed explanation of this application and should not be construed as limiting the specific implementation of this application to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of this application, and all such modifications or substitutions should be considered within the scope of protection of this application.

Claims

1. A method for manufacturing a display panel, characterized in that, Including the following steps: Provide a substrate; The evaporation source is controlled to emit luminescent material particles toward the substrate. When the luminescent material particles pass through the openings of the mask, the directionality of the evaporation beam of the luminescent material particles is controlled by the mask, thereby improving the uniformity of the evaporation beam of the luminescent material particles at least one opening. Multiple light-emitting layers are formed on the substrate. The mask has multiple openings, and at least two of the openings are not equidistant from the evaporation source.

2. The method for manufacturing a display panel according to claim 1, characterized in that, The mask is provided with multiple deformation structures, which are disposed within the openings; The step of controlling the directionality of the evaporation beam of the luminescent material particles through the mask when the luminescent material particles pass through the opening of the mask, thereby improving the uniformity of the evaporation beam of the luminescent material particles through at least one opening, includes: The deformation of at least one of the openings is controlled to reduce the radial width of the opening at the location of the deformation structure, thereby forming a slit. When the luminescent material particles pass through the opening in the mask, the uniformity of the evaporation beam of the luminescent material particles is improved after passing through the slit.

3. The method for manufacturing a display panel according to claim 2, characterized in that, The greater the distance between the opening and the evaporation source, the greater the radial width of the slit within the opening; Alternatively, the greater the distance between the opening and the evaporation source, the farther the slit within the opening is from the evaporation source.

4. The method for manufacturing a display panel according to claim 2, characterized in that, In the direction from the evaporation source toward the substrate, the radial width of the slit first gradually decreases and then gradually increases; The maximum width of the slit is equal to the width of the opening; The deformable structure is formed of a piezoelectric material, and the deformable structure deforms under the control of an electrical signal to narrow the radial width of the opening to form a slit.

5. The method for manufacturing a display panel according to claim 2, characterized in that, The step of providing a substrate includes: Provide a substrate; A patterned bottom electrode is formed on the substrate. A pixel definition layer is formed on the bottom electrode, the pixel definition layer having multiple opening regions, and the bottom electrode being exposed from the opening regions; wherein, between two bottom electrodes, the width of the pixel definition layer gradually increases toward the side away from the substrate. The step of controlling the evaporation source to emit luminescent material particles toward the substrate includes: Provide a mask; Align the multiple openings on the mask with the multiple opening areas on the substrate one by one; The evaporation source is controlled to emit luminescent material particles toward the substrate. The step of forming multiple light-emitting layers on the substrate includes: At each of the said opening regions, a light-emitting layer is formed on the bottom electrode; wherein the multiple light-emitting layers have the same thickness.

6. A photomask, characterized in that, The method for manufacturing a display panel as described in any one of claims 1 to 5, wherein the mask comprises a mask body, a plurality of openings disposed on the mask body, and a plurality of deformable structures disposed within the plurality of openings; The deformable structure is used to deform under the control of an electrical signal, so that the radial width of the opening at the location of the deformable structure narrows to form a slit.

7. The photomask according to claim 6, characterized in that, The mask body includes a first mask and a second mask, with a gap between the first mask and the second mask; the first mask and the second mask are respectively provided with a plurality of mesh holes, and in a direction perpendicular to the first mask, the mesh holes of the first mask and the mesh holes of the second mask form an opening, which is used to allow luminescent material particles to pass through; The deformation structure is disposed between the first mask and the second mask, and is disposed within the opening; The mask body includes a first central region, which is configured to correspond with the evaporation source during the light-emitting layer fabrication process; The greater the distance between the opening and the first central region, the smaller the radial width of the slit within the opening; The greater the distance between the opening and the first central area, the farther the slit in the opening is from the first mask.

8. The photomask according to claim 7, characterized in that, In the direction from the evaporation source toward the substrate, the radial width of the slit first gradually decreases and then gradually increases; the maximum width of the slit is equal to the width of the opening. The deformable structure is formed of a piezoelectric material, and the deformable structure deforms under the control of an electrical signal to narrow the radial width of the opening to form a slit.

9. A display panel, characterized in that, The display panel is formed by the manufacturing method of the display panel as described in any one of claims 1-5. The display panel includes a substrate, a pixel definition layer disposed on the substrate, and a plurality of light-emitting units. The pixel definition layer is provided with a plurality of opening areas, and the plurality of light-emitting units are respectively disposed in the plurality of opening areas. Two adjacent light-emitting units are separated by the pixel definition layer. The light-emitting unit includes a bottom electrode, a light-emitting layer, and a top electrode. The light-emitting layer is disposed between the bottom electrode and the top electrode, and the multiple light-emitting layers have the same thickness.

10. The display panel according to claim 9, characterized in that, Between the two bottom electrodes, the width of the pixel definition layer gradually increases toward the side away from the substrate. The substrate includes a second central region, which is configured to correspond to the evaporation source during the light-emitting layer fabrication process. The further away from the opening region is from the second central region, the smaller the radial width of the opening region and the larger the maximum width of the adjacent pixel definition layer.

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