This application claims priority to Chinese Patent Application No. 202011548822.5 filed to the CNIPA on Dec. 24, 2020 and entitled “Mask, and Manufacturing Method for Mask”, the entire contents of which are incorporated herein by reference.
The disclosure relates to the technical field of semiconductors, in particular to a mask, and a manufacturing method for the mask.
At present, an evaporation process is usually adopted for manufacturing an organic light-emitting diode (OLED) display panel, and a mask is an important device in the evaporation process. The mask has a hollowed-out pattern formed by a plurality of evaporation holes, and vapor of an organic light-emitting material is deposited onto a predetermined position on the substrate through the evaporation holes in the mask during evaporation, thus forming an organic light-emitting layer pattern corresponding to the pattern of the evaporation holes.
However, the problem of the easy occurrence of color mixing due to the inaccurate position of evaporation when a pattern of a light-emitting substrate is formed by means of a mask exists in the prior art.
The disclosure provides a mask, and a manufacturing method for the mask, aiming to solve the problem in the prior art of the easy occurrence of color mixing due to the inaccurate position of evaporation when a pattern of a light-emitting substrate is formed by means of a mask.
An embodiment of the disclosure provides a mask applied for shielding a mother substrate subject to a multi-division exposure procedure, where the mother board has a substrate invalid region with no exposure chance due to the multi-division exposure procedure, where the mask includes: a metal frame; a frame mask, disposed on a side of the metal frame, and including a hollowed-out region and a frame surrounding the hollowed-out region; at least one fine metal strip mask, disposed on a side of the frame mask facing away from the metal frame, and provided with a plurality of openings for evaporation of a light-emitting film in sub-pixels on the mother substrate; and a support plate, disposed between the metal frame and the fine metal strip mask for shielding the substrate invalid region, wherein a thickness of the support plate is greater than a thickness of the frame mask.
In a possible embodiment, the fine metal strip mask comprises a plurality of evaporation regions, where each evaporation region corresponds to one light-emitting sub-substrate in the mother substrate, and the openings are located in the evaporation regions.
In a possible embodiment, the hollowed-out region of the frame mask is divided into a plurality of evaporation openings, where each evaporation opening corresponds to one light-emitting sub-substrate in the mother substrate; and the openings are distributed throughout the fine metal strip mask.
In a possible embodiment, the support plate and the frame mask are of an integrated structure.
In a possible embodiment, the frame includes an inner frame and an outer frame surrounding the inner frame, wherein the side of the outer frame facing away from the metal frame is thinned relative to the inner frame, and the frame mask is welded to the metal frame at the position of the outer frame.
In a possible embodiment, a ratio of the thickness of the inner frame to the thickness of the support plate is in a range of 0.9-1.1.
In a possible embodiment, the thickness of the outer frame is 10%-50% of the thickness of the support plate.
In a possible embodiment, within a surface of the frame mask facing the metal frame and in a direction perpendicular to an extending direction of the fine metal strip mask, a width of the outer frame is one-fifth to two-thirds of a width of the frame of the frame mask; and within the surface of the frame mask facing the metal frame and in the direction perpendicular to the extending direction of the fine metal strip mask, a width of the outer frame is one-fourth to three-fourths of a width of the metal frame.
In a possible embodiment, the support plate and the frame mask are two separate components; two ends of the support plate are welded to two opposite sides of the metal frame, respectively.
In a possible embodiment, the support plate is provided with a welding portion overlapping with the metal frame, and a thickness of the welding portion is 10%-50% of a thickness of a portion other than the welding portion of the support plate.
In a possible embodiment, the metal frame is provided with a first groove at a position corresponding to the welding portion, and the depth of the first groove is greater than or equal to the thickness of the welding portion.
In a possible embodiment, an outer edge of the frame mask is provided with a plurality of protruding portions welded to the metal frame; the metal frame is provided with second grooves at positions corresponding to the protruding portions, and the depth of the second groove is greater than or equal to the thickness of the protruding portion.
In a possible embodiment, the depth of the first groove is greater than the depth of the second groove.
In a possible embodiment, an orthographic projection of the protruding portion on the metal frame does not overlap with an orthographic projection of the welding portion on the metal frame.
In a possible embodiment, the depth of the second groove is equal to the thickness of the protruding portion; and the difference between the depth of the first groove and the thickness of the welding portion is the same as the depth of the second groove.
In a possible embodiment, the thickness of the support plate is 0.5 mm-3 mm.
In a possible embodiment, the metal frame is further provided with a plurality of transfer grooves.
An embodiment of the disclosure also provides a manufacturing method for the mask according to embodiments of the disclosure, including: providing the metal frame; welding the support plate and the frame mask to one side of the metal frame; and stretching the fine metal strip mask and welding the stretched fine metal strip mask to a side of the frame mask facing away from the metal frame.
In a possible embodiment, the support plate and the frame mask are of an integrated structure; the frame mask includes a hollowed-out region, and a frame surrounding the hollowed-out region, the frame includes an inner frame and an outer frame surrounding the inner frame, the side of the outer frame facing away from the metal frame is thinned relative to the inner frame, and the frame mask is welded to the metal frame at the position of the outer frame. The welding the frame mask to the side of the metal frame includes welding the outer frame of the frame mask to the metal frame.
In a possible embodiment, the stretching the fine mask strip and welding the stretched fine metal strip mask to a side of the frame mask facing away from the metal frame includes: stretching the fine metal strip mask obliquely towards the frame mask side to enable the fine metal strip mask to be fully attached to the frame mask; and welding the fine metal strip mask in a stretched state to the frame mask at the position of the inner frame.
In one possible embodiment, the support plate and the frame mask are two separate components, the support plate is provided with a welding portion overlapping with the metal frame, the metal frame is provided with a first groove at a position corresponding to the welding portion, and the metal frame is provided with second grooves at positions welded to the frame mask. The welding a support plate to one side of the metal frame includes: welding the welding portion of the support plate into the first groove of the metal frame.
In a possible embodiment, an outer edge of the frame mask is provided with a plurality of protruding portions welded to the metal frame. The welding the frame mask to one side of the metal frame includes: stretching the frame mask and welding the protruding portions of the stretched frame mask into the second grooves of the metal frame.
The beneficial effects of embodiments of the disclosure are as follows: in embodiments of the disclosure, the mask further includes the support plate, and the thickness of the support plate is greater than the thickness of the frame mask. When the mask is specifically manufactured, since the support plate has a greater thickness and larger rigidity, and is not easy to deform, the support plate can be directly welded to the metal frame without stretching, and will not collapse or bend, thereby avoiding the situation that when the method of shielding substrate invalid region adopts a frame mask or fine metal mask which is not provided with openings at corresponding positions in the prior art, the problem of poor shadow and color mixing due to uneven stress distribution is prone to occur during the tensioning process. Moreover, since the support plate has a larger thickness, a structure above the support plate (i.e. fine metal strip mask) can be effectively supported by the support plate, thereby further reducing the risk of overall sagging of a metal mask assembly.
In order to make the objectives, technical solutions and advantages of embodiments of the disclosure clearer, the technical solutions of embodiments of the disclosure will be clearly and completely described below in conjunction with the accompanying drawings of embodiments of the disclosure. Obviously, the described embodiments are some, but not all, embodiments of the disclosure. All other embodiments obtained by a person of ordinary skill in the art based on the described embodiments of the disclosure without creative work fall within the protection scope of the disclosure.
Unless otherwise defined, technical or scientific terms used in the disclosure shall have the ordinary meaning as understood by a person of ordinary skill in the art to which the disclosure belongs. The words such as “first” and “second”, as used in the disclosure, do not denote any order, quantity, or importance, but are merely used to distinguish different components. The words such as “including” or “containing” mean that elements or items appearing before the word encompass elements or items listed appearing after the word and equivalents thereof, but do not exclude other elements or items. The words such as “connected” or “connection” are not restricted to physical or mechanical connection, but may include electrical connection, whether direct or indirect. The words such as “up, “down”, “left” and “right” are only used to indicate the relative positional relationship, and when the absolute position of the described object changes, the relative positional relationship may also change accordingly.
In order to keep the following description of embodiments of the disclosure clear and concise, the disclosure omits detailed descriptions of known functions and known components.
In the process of preparing an organic light-emitting display panel, a photomask of each generation has a fixed size, and has a fixed effective exposure region. When the size of an evaporated substrate is small, the effective exposure region of the photomask may be divided into different regions with different exposure patterns. In the process of translating and aligning the substrate, different exposure regions (shot) of the substrate can be achieved by one photomask, as shown in
In the process of evaporating all layers of organic light-emitting materials onto the substrate, corresponding metal masks are used, and include fine metal masks and common metal masks, for evaporating red (R), green (G), blue (B) pixel light-emitting materials, and organic or metal materials on common layers, respectively. In order to prevent the organic materials from being evaporated onto the substrate, it is necessary to block the position corresponding to the corresponding substrate invalid region on the metal mask. In the manufacturing process of a conventional metal mask assembly, in order to make the fine metal mask and the substrate completely fit, and the organic material be accurately evaporated onto the corresponding position on the organic light-emitting substrate, it is necessary to perform tensioning on a frame mask (F-mask) and a fine metal mask (FMM) and then laser-weld the stretched masks to a metal frame to assemble the masks into a complete mask (MFA). If in the method of shielding the substrate invalid region, the F-mask or the FMM is not provided with openings at corresponding positions, the problem of poor shadow and color mixing due to uneven stress distribution is prone to occur during the tensioning process.
In view of this, referring to
a metal frame 1;
a frame mask 2, on a side of the metal frame 1, and including a hollowed-out region 22, and a frame 21 surrounding the hollowed-out region;
at least one fine metal strip mask 3, on the side of the frame mask 2 facing away from the metal frame 1, and provided with a plurality of openings 30 for the evaporation of a light-emitting film in sub-pixels in the mother substrate; and
a support plate 4, between the metal frame 1 and the fine metal strip mask 2 for shielding the substrate invalid region, wherein the thickness of the support plate 4 is greater than the thickness of the frame mask 2.
In embodiments of the disclosure, the mask further includes the support plate, and the thickness of the support plate is greater than the thickness of the frame mask. When the mask is manufactured, since the support plate has a greater thickness and larger rigidity, and is not easy to deform, the support plate can be directly welded to the metal frame without stretching, and will not collapse or bend, thereby avoiding the situation that when the method of shielding substrate invalid region adopts a frame mask or fine metal mask which is not provided with openings at corresponding positions in the prior art, the problem of poor shadow and color mixing due to uneven stress distribution is prone to occur during the tensioning process. Moreover, since the support plate has a greater thickness, a structure above the support plate (i.e. fine metal strip mask) can be effectively supported by the support plate, thereby further reducing the risk of overall sagging of a metal mask assembly.
In specific implementation, the support plate 4 and the frame mask 2 may be of an integrated structure, as shown in
In specific implementation, referring to
In specific implementation, referring to
In specific implementation, the thickness of the outer frame 212 is 10%-50% of the thickness of the support plate 4.
In specific implementation, referring to
Specifically, referring to
In specific implementation, referring to
In specific implementation, referring to
In specific implementation, referring to
Specifically, referring to
Specifically, referring to
In specific implementation, referring to
In specific implementation, the evaporation pattern of the mask may be various, specifically, for example, referring to
In specific implementation, the thickness of the support plate 4 is 0.5 mm-3 mm.
In specific implementation, referring to
Based on the same inventive concept, an embodiment of the disclosure further provides a manufacturing method for the mask according to embodiments of the disclosure, referring to
S100: providing a metal frame;
S200: welding a support plate and a frame mask to one side of the metal frame; and
S300: stretching a fine metal strip mask and welding the stretched fine metal strip mask to the side of the frame mask facing away from the metal frame.
In specific implementation, when the mask is of the structure shown in
Correspondingly, S300 of stretching the fine metal strip mask and welding the stretched fine metal strip mask to the side of the frame mask facing away from the metal frame includes:
stretching the fine metal strip mask obliquely towards the frame mask side to enable the fine metal strip mask to be fully attached to the frame mask; and
welding the fine metal strip mask in a stretched state to the frame mask at the position of the inner frame.
In embodiments of the disclosure, when the support plate and the frame mask are of an integrated structure, since the support plate itself is thick and has large rigidity, it is possible to directly weld the frame mask to the frame without stretching, and it is only necessary to tension and stretch the fine metal strip mask, so that the situation that the frame mask needs to be welded after stretching is avoided, and the steps of manufacturing the mask can be simplified.
In specific implementation, when the mask is of the structure shown in
Correspondingly, S200 of welding a support plate to one side of the metal frame includes welding the welding portions of the support plate into the first grooves of the metal frame.
Specifically, the outer edge of the frame mask is provided with a plurality of protruding portions welded to the metal frame; S200 of welding a frame mask to one side of the metal frame includes stretching the frame mask and welding the protruding portions of the stretched frame mask into the second grooves of the metal frame.
In embodiments of the disclosure, the mask further includes the support plate, and the thickness of the support plate is greater than the thickness of the frame mask. When the mask is specifically manufactured, since the support plate has a larger thickness and larger rigidity, and is not easy to deform, the support plate can be directly welded to the metal frame without stretching, and will not collapse or bend, thereby avoiding the situation that when the method of blocking a substrate invalid region adopts a frame mask or fine metal mask which is not provided with openings at corresponding positions in the prior art, the problem of poor shadow and color mixing due to uneven stress distribution is prone to occur during the tensioning process. Moreover, since the support plate has a larger thickness, a structure above the support plate (i.e. fine metal strip mask) can be effectively supported by the support plate, thereby further reducing the risk of overall sagging of a metal mask assembly.
It will be apparent to those skilled in the art that various modifications and variations may be made to the disclosure without departing from the spirit and scope of the disclosure. Thus, if these modifications and variations of the disclosure fall within the scope of the claims of the disclosure and their equivalents, the disclosure is also intended to include these modifications and variations.
Number | Date | Country | Kind |
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202011548822.5 | Dec 2020 | CN | national |
Filing Document | Filing Date | Country | Kind |
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PCT/CN2021/125631 | 10/22/2021 | WO |