Mask and preparation method thereof, mask assembly and evaporation equipment

Abstract

The invention provides a mask, a preparation method of the mask, a mask assembly and evaporation equipment. The mask comprises a plurality of first openings arranged in an array and a supporting part defining the first openings, and the supporting part comprises a middle area and an edge area located on the periphery of the middle area. The mask further comprises two opposite faces, the supporting structure located in the edge area is arranged on at least one of the two opposite faces, the supporting structure is used for providing supporting force facing the substrate to be evaporated, the edge of the mask can be attached to the substrate to be evaporated more tightly, and the bad problems such as color mixing are solved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a mask plate and a preparation method thereof, a mask plate assembly, and an evaporation device. Background Art

[0002] OLED (Organic Light Emitting Diode) is gradually replacing liquid crystal display (LCD) due to its advantages such as lightness, self-luminescence, wide viewing angle, fast response speed, low brightness and low power consumption.

[0003] In OLED manufacturing technology, the mask used for vacuum evaporation is a crucial component. In order to reduce the color mixing and other undesirable problems caused by evaporation, the evaporation equipment uses a magnetic field to improve the close bonding between the mask and the substrate to be evaporated, but it still cannot avoid the color mixing and other undesirable problems caused by the sagging of the mask edge. Summary of the invention

[0004] In view of this, the purpose of the present application is to propose a mask and a preparation method thereof, a mask assembly, and an evaporation device to solve or partially solve the above-mentioned problems.

[0005] Based on the above-mentioned purpose, in a first aspect of the present application, a mask plate is provided, comprising a plurality of first openings arranged in an array and a supporting portion defining the plurality of first openings, the supporting portion comprising a central region and an edge region located at the periphery of the central region, the mask plate comprising two opposite surfaces, a supporting structure being provided on at least one of the two opposite surfaces, and the supporting structure being located in the edge region.

[0006] In a second aspect of the present application, a mask assembly is provided, comprising:

[0007] A first mask, wherein the first mask is the mask as described in the first aspect;

[0008] A frame, the first mask is fixed on the frame, and the frame includes a first frame and a second frame opposite to each other;

[0009] A plurality of second masks stacked on the first mask, the plurality of second masks are arranged in sequence along the direction in which the first frame and the second frame extend, and two ends of each of the second masks are fixed on the first frame and the second frame respectively;

[0010] The supporting structure of the first mask provides supporting force for the edges of the plurality of second mask plates in a direction away from the first mask plate.

[0011] In a third aspect of the present application, a vapor deposition device is provided, comprising the mask assembly as described in the second aspect.

[0012] In a fourth aspect of the present application, a method for preparing a mask is provided, wherein the mask includes two opposite surfaces, and the preparation method includes:

[0013] A plurality of first openings arranged in an array and a support portion defining the plurality of first openings, the support portion comprising a middle region and an edge region located at the periphery of the middle region;

[0014] A supporting structure is provided on at least one of the two opposite surfaces, and the supporting structure is located in the edge region.

[0015] From the above, it can be seen that the present application provides a mask plate and a preparation method thereof, a mask plate assembly, and an evaporation device. The mask plate includes a plurality of first openings arranged in an array and a support portion defining the plurality of first openings, and the support portion includes a central region and an edge region located outside the central region. The mask plate also includes two opposite surfaces, and a support structure located in the edge region is provided on at least one of the two opposite surfaces, so that the support structure provides a support force toward the substrate to be evaporated, so that the edge of the mask plate can be more closely attached to the substrate to be evaporated, thereby improving problems such as color mixing. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present application or related technologies, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 A schematic structural diagram of an exemplary evaporation device according to an embodiment of the present application is shown.

[0018] Figure 2 A schematic top view of the structure of an exemplary mask assembly according to an embodiment of the present application is shown.

[0019] Figure 3A A schematic diagram of an exemplary magnet is shown.

[0020] Figure 3B A side structural schematic diagram of an exemplary mask assembly according to an embodiment of the present application is shown.

[0021] Figure 3C A side structural schematic diagram of another exemplary mask assembly according to an embodiment of the present application is shown.

[0022] Figure 3DA schematic diagram showing shadows according to an embodiment of the present application is shown.

[0023] Figure 4A A schematic structural diagram of an exemplary mask according to an embodiment of the present application is shown.

[0024] Figure 4B A schematic structural diagram of an exemplary mask assembly according to an embodiment of the present application is shown.

[0025] Figure 4C A schematic structural diagram of another exemplary mask assembly according to an embodiment of the present application is shown.

[0026] Figure 4D A schematic top view of an exemplary limiting structure according to an embodiment of the present application is shown.

[0027] Figure 4E An exemplary embodiment according to the present application is shown. Figure 4D A schematic cross-sectional view of the mask obtained by cutting along the BB' direction.

[0028] Figure 4F A schematic diagram of an exemplary ring structure according to an embodiment of the present application is shown.

[0029] Figure 4G A schematic diagram showing the distribution of an exemplary annular structure in a limiting structure according to an embodiment of the present application is shown.

[0030] Figure 4H A schematic diagram showing the distribution of another exemplary annular structure in a limiting structure according to an embodiment of the present application is shown.

[0031] Fig. 4I and Figure 4J A schematic side view of an exemplary magnetic structure in a mask according to an embodiment of the present application is shown.

[0032] Figure 4K and Figure 4L A schematic side view of an exemplary magnetic structure in a mask according to an embodiment of the present application is shown.

[0033] Figure 5A A schematic structural diagram of another exemplary mask according to an embodiment of the present application is shown.

[0034] Figure 5B A schematic diagram showing the distribution of an exemplary buoyancy structure in a limiting structure according to an embodiment of the present application is shown.

[0035] Figure 5C An exemplary embodiment according to the present application is shown. Figure 5B A schematic cross-sectional view of the mask obtained by cutting along the CC' direction.

[0036] Figure 6 A schematic flow chart of an exemplary method for preparing a mask according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0037] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0038] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should be the usual meanings understood by people with ordinary skills in the field to which the present application belongs. The "first", "second" and similar words used in the embodiments of the present application do not represent any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing in front of the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0039] OLED (Organic Light Emitting Diode) display technology is recognized by the industry as the third generation display technology for its advantages such as lightness, self-luminescence, wide viewing angle, fast response speed, low brightness and low power consumption. It has become the main development direction in the field of display technology. At present, in the field of flat panel display such as mobile phones, PDAs (Personal Digital Assistants), digital cameras, OLED display devices have begun to replace traditional liquid crystal displays (LCD).

[0040] The light-emitting layer of the OLED display device is mainly produced by evaporating the light-emitting material onto the substrate through a mask evaporation method. An evaporation mask, such as a fine metal mask (FMM) is set in front of the substrate as a shielding layer, and the organic light-emitting pixels are evaporated into the corresponding unit pixels of the substrate through the mask openings.

[0041] Figure 1 A schematic structural diagram of an exemplary evaporation device 100 according to an embodiment of the present application is shown.

[0042] like Figure 1As shown, the evaporation device 100 may include a mask assembly 102 and a magnetic plate 104 , and the magnetic plate 104 may be composed of one or more magnetic blocks. A substrate 106 to be evaporated is placed between the mask assembly 102 and the magnetic plate 104 .

[0043] During evaporation, the magnetic plate 104 can generate a magnetic field, so that the evaporation mask in the mask assembly 102 is adsorbed along the direction A onto the substrate 106 to be evaporated.

[0044] The evaporation device 100 may further include an evaporation source 108, on which the evaporation material is disposed, and the evaporation material is heated by the evaporation source 108, so that the atoms or molecules of the evaporation material are vaporized from the surface to form a vapor flow, which is incident on the surface of the substrate 106 to be evaporated, and condensed to form a solid film. It can be understood that Figure 1 It only exemplarily shows several important mechanisms in the evaporation equipment and does not constitute a limitation of the embodiments of the present application.

[0045] The mask assembly 102 may include a first mask 1022 and a second mask 1024 (eg, an evaporation mask) stacked on the first mask 1022 (eg, a supporting mask (Full Sheet)).

[0046] Figure 2 A schematic top view of an exemplary mask assembly 102 according to an embodiment of the present application is shown.

[0047] like Figure 2 As shown, the mask assembly 102 may include a frame 202, a first mask 1022, and a second mask 1024 stacked on the first mask 1022. The first mask 1022 is fixed on the frame 202, and the frame 202 may include a first frame 2022 and a second frame 2024 relative to each other, and a third frame 2026 and a fourth frame 2028 relative to each other, wherein the grippers 204 (gripper) at the edges of the first mask 1022 may be welded to the frame of the frame 202 to fix the first mask 1022 on the frame 202.

[0048] The second mask 1024 may be in the shape of a long strip, including two opposite long sides 206 extending along the first direction X and two opposite short sides 208 extending along the second direction Y. The two ends of the second mask 1024 (i.e., the two opposite short sides 208) may be fixed to the first frame 2022 and the second frame 2024 of the frame 202, respectively, and the two ends of the plurality of second masks 1024 are sequentially arranged along the direction in which the first frame 2022 and the second frame 2024 extend.

[0049] The first mask 1022 may include a plurality of first openings 210 arranged in an array, and the second mask 1024 may include a plurality of second openings, and the plurality of second openings correspond one to one with the plurality of first openings 210. The first mask 1022 may be used to support the second mask 1024 and define a plurality of vapor deposition areas (display areas) of the to-be-deposited substrate 106 through the plurality of first openings 210.

[0050] Figure 3A A schematic diagram of an exemplary magnet is shown.

[0051] like Figure 3A As shown, when the magnet 302 attracts the iron nail 304, the iron nail 304 will be magnetized and have magnetic properties, so the iron nail 306 will also be attracted by the iron nail 304. At the same time, under the action of gravity, the iron nail 306 will also have a relative pulling force on the iron nail 304.

[0052] Figure 3B A side structural schematic diagram of an exemplary mask assembly 102 according to an embodiment of the present application is shown. Figure 3C A side structural schematic diagram of another exemplary mask assembly 102 according to an embodiment of the present application is shown. Figure 3D A schematic diagram showing shadows according to an embodiment of the present application is shown.

[0053] Based on the above principles, under normal circumstances, if Figure 3B As shown, the first mask 1022 and the second mask 1024 are subjected to a force upward in direction A under the magnetic force of the magnetic plate 104, which forces the first mask 1022 and the second mask 1024 to be closely attached to the substrate 106 to be evaporated, so as to evaporate a pattern with a better effect. The first mask 1022 also exerts a pulling force on the second mask 1024 in the direction opposite to direction A. However, if Figure 3C As shown, for some small-sized display panels or special-shaped display panel designs, due to the small number of magnetic blocks in the magnetic plate 104, the adsorption force of the magnetic plate 104 is weak. At the same time, the clamps 204 on the edges of the first mask 1022 will also be magnetized, thereby generating a pulling force on the edge position of the second mask 1024 in a direction opposite to direction A. In this way, the edge position of the second mask 1024 cannot be effectively adsorbed under the combined action of the magnetized clamps 204, the magnetic force of the first mask 1022, and the gravity of the frame 202, resulting in the existence of position 308 between the second mask 1024 and the substrate to be evaporated 106. In this way, during evaporation, a shadow will be generated at the position 308 that cannot be effectively bonded, such as Figure 3D As shown, this causes color mixing at the edge of the evaporated substrate.

[0054] In order to at least solve the above problems, the present application provides a mask plate and a preparation method thereof, a mask plate assembly, and an evaporation device. The mask plate includes a plurality of first openings arranged in an array and a support portion defining the plurality of first openings, and the support portion includes a central region and an edge region located outside the central region. The mask plate also includes two opposite surfaces, and a support structure located in the edge region is provided on at least one of the two opposite surfaces, so that the support structure provides a support force toward the substrate to be evaporated, so that the edge of the mask plate can be more closely attached to the substrate to be evaporated, thereby improving the problem of color mixing and other defects.

[0055] Back to Figure 2 The first mask 1022 may include a plurality of first openings 210 arranged in an array and a support portion 402 defining the plurality of first openings 210. The support portion 402 may include a middle region 4022 and an edge region located outside the middle region. The first mask 1022 may also include two opposite surfaces.

[0056] Figure 4A FIG. 4 is a schematic structural diagram of an exemplary mask 400 according to an embodiment of the present application. The mask 400 may be the first mask 1022 .

[0057] like Figure 4A As shown, the two opposite surfaces of the mask 400 may include a first surface 404 and a second surface 406. In order to make the edge of the second mask 1024 stacked on the mask 400 effectively fit the substrate 106 to be evaporated, in some implementations, a support structure 408 may be provided on at least one of the two opposite surfaces, and the support structure 408 is located in the edge area. The support structure 408 of the first mask 1022 can provide a support force for the edges of the plurality of second masks 1024 in a direction away from the first mask 1022. In this way, the support structure 408 can play a supporting role for the second mask 1024 to be attached to the substrate 106 to be evaporated along the direction A, so that the second mask 1024 effectively fits the substrate 106 to be evaporated, avoiding the generation of the edge gap of the second mask 1024, and solving the edge color mixing problem of the evaporated substrate.

[0058] like Figure 4AAs shown, in some implementations, a limiting structure 410 may be further provided on at least one of the two opposite surfaces, the limiting structure 410 may be located in the edge region, and the support structure 408 may be disposed in the limiting structure 410 in a one-to-one correspondence. In some embodiments, the limiting structure 410 may be a groove, so that one side of the limiting structure 410 is open along the direction A, which can ensure that the support force of the support structure 408 acts upward along the direction A on the edge position of the second mask 1024. In some implementations, the depth of the limiting structure 410 in the direction A may be less than or equal to half of the thickness of the mask 400 in the direction A, so as to avoid the depth of the limiting structure 410 being too large, resulting in a weakening of the support force of the support structure 408 acting on the second mask 1024.

[0059] Figure 4B A schematic structural diagram of an exemplary mask assembly 420 according to an embodiment of the present application is shown.

[0060] like Figure 4B As shown, in some implementations, the shape of the limiting structure 410 can be adapted to the shape of the first opening 210, and the limiting structure 410 can be arranged around each first opening 210 located in the edge region. In this way, the support structure 408 arranged in the limiting structure 410 and the edge of the second mask 1024 can have a sufficiently large contact area, so that the edge of the second mask 1024 can completely fit the substrate 106 to be evaporated.

[0061] like Figure 4B As shown, in some embodiments, the distance d between the side of the limiting structure 410 away from the middle area 4022 and the edge of the mask 400 is greater than or equal to 100 microns, so as to prevent the limiting structure 410 from being too close to the frame 202 and being constrained by the clamp 204 on the frame 202 (for example, affected by the gravity of the clamp 204), so that the support structure 408 in the limiting structure 410 cannot provide effective supporting force, so that the edge area of ​​the second mask 1024 cannot effectively fit the substrate 106 to be evaporated.

[0062] Figure 4C FIG. 4 is a schematic structural diagram of another exemplary mask assembly 420 according to an embodiment of the present application.

[0063] like Figure 4C As shown, as an optional embodiment, the shape of the limiting structure 410 can be the same as the shape of the mask 400, and the limiting structure can be arranged around the side of the plurality of first openings 210 away from the middle area 4022. In this way, the support structure 408 in the limiting structure 410 located at the edge of the mask 400 can also play a supporting role for the edge of the second mask 1024.

[0064] Back to Figure 4A, the two opposite surfaces may include a first surface 404. In some embodiments, a support structure 408 may be located on the first surface 404, and the support structure 408 may include a deformable structure and / or a magnetic structure. The deformable structure is configured to: deform when heated and the deformation can provide a supporting force to a supported object (e.g., the second mask 1024) located at the position of the deformation; the magnetic structure is configured to: move in a direction away from the mask 400 under the action of an external magnetic field to provide a supporting force to a supported object (e.g., the second mask 1024) located at the position of the magnetic structure. In this way, the support structure 408 can provide a supporting force to the edge area of ​​the second mask 1024 toward the substrate to be evaporated 106, so that the edge area of ​​the second mask 1024 can be attached to the substrate to be evaporated 106, avoiding the generation of a gap in the edge area of ​​the second mask 1024, and solving the edge color mixing problem of the evaporated substrate.

[0065] Figure 4D A schematic top view of an exemplary limiting structure 410 according to an embodiment of the present application is shown.

[0066] like Figure 4D As shown, when the support structure 408 is located on the first surface 404, the deformable structure may include a first airbag 412, the first airbag 412 is internally connected, and during evaporation, the first airbag 412 may be filled with heated expandable gas.

[0067] Figure 4E An exemplary embodiment according to the present application is shown. Figure 4D A schematic cross-sectional view of the mask plate 400 obtained by cutting along the BB' direction in FIG.

[0068] like Figure 4E As shown, since the first airbag 412 is constrained by the left side 4102, the bottom 4104 and the right side 4106 of the limiting structure 410, the first airbag 412 filled with gas expands in a direction away from the mask 400 (for example, along direction A) when heated to protrude from the first surface 404, so that the edge area of ​​the second mask 1024 in contact with the first airbag 412 can be attached to the substrate to be evaporated 106. Exemplarily, the gas filled in the first airbag 412 can include stable gases such as nitrogen and helium, which can extend the service life of the first airbag 412 and reduce the replacement cost of the first airbag 412.

[0069] Figure 4F A schematic diagram of an exemplary ring structure 414 according to an embodiment of the present application is shown.

[0070] like Figure 4FAs shown, in some embodiments, the deformable structure may also include an annular structure 414 made of nickel-titanium alloy, the annular structure 414 is deformable when heated, and the deformed annular structure 414 includes at least one curved portion 4142, the curved portion 4142 protrudes from the first surface 404 in a direction away from the mask 400, so that the edge area of ​​the second mask 1024 in contact with the curved portion 4142 can be attached to the substrate 106 to be evaporated. Exemplarily, the annular structure 414 can be a wave spring made of a shape memory alloy material with thermal effect. During evaporation, the annular structure 414 is deformable when heated, and the deformed annular structure 414 can return to its original shape under normal temperature.

[0071] Figure 4G A schematic diagram showing the distribution of an exemplary annular structure 414 in a limiting structure 410 according to an embodiment of the present application is shown.

[0072] like Figure 4G As shown, in some embodiments, the limiting structure 410 may include an annular groove 416 whose shape matches the first opening 210, and a plurality of annular structures 414 may be evenly distributed in the annular groove 416, and the outer diameter a of the annular structure 414 matches the width b of the annular groove 416. The supporting force provided by the curved portions of the evenly distributed multiple annular structures 414 may be evenly distributed in the edge area of ​​the second mask 1024, so that the edge area of ​​the second mask 1024 may be fitted with the substrate 106 to be evaporated.

[0073] Figure 4H A schematic diagram showing the distribution of another exemplary annular structure 414 in the limiting structure 410 according to an embodiment of the present application is shown.

[0074] like Figure 4H As shown, in some embodiments, the shape of the annular structure 414 can also match the shape of the annular groove 416 and be arranged one-to-one in the annular groove 416. In this way, the support force provided by the curved portions of the multiple annular structures 414 can enable the edge area of ​​the second mask 1024 to fit with the substrate 106 to be evaporated.

[0075] Fig. 4I and Figure 4J A schematic side view of an exemplary magnetic structure 418 in a mask 400 according to an embodiment of the present application is shown.

[0076] like Fig. 4IAs shown, in some embodiments, the magnetic structure 418 may include a magnetic component 4182 and a movable component 4184 connected to the magnetic component 4182, one end of the movable component 4184 is connected to the magnetic component 4182, and the other end of the movable component 4184 is connected to the limiting structure 410 (for example, connected to the bottom 4104 of the limiting structure 410) to be fixed by the limiting structure 410, and the magnetic component 4182 is supported by the movable component 4184 and moves in a direction away from the mask 400 under the action of the external magnetic field to protrude from the first surface 404, as shown in FIG. Figure 4J As shown. The magnetic component 4182 protruding from the first surface 404 can support the edge area of ​​the mask 1024 so that the edge area of ​​the mask 1024 fits the substrate 106 to be evaporated. The magnetic component 4182 can be made of magnetic materials such as iron, cobalt, and nickel, and the movable component 4184 can be made of non-magnetic materials such as aluminum and copper.

[0077] Figure 4K and Figure 4L A schematic side view of an exemplary magnetic structure 420 in a mask 400 according to an embodiment of the present application is shown.

[0078] like Figure 4K As shown, in some embodiments, the magnetic structure 420 may include a magnetic particle 4202 packaging film 4204, the packaging film 4204 covers the opening of the limiting structure 410, the magnetic particle 4202 is movably located in the limiting structure 410, and the magnetic particle 4202 can lift the packaging film 4204 under the action of the magnetic field adsorption force to protrude from the first surface 404, as shown in FIG. Figure 4L As shown. The packaging film 4204 protruding from the first surface 404 can lift up the edge area of ​​the mask 1024 so that the edge area of ​​the mask 1024 is attached to the substrate to be evaporated 106. The packaging film 4204 can be made of high temperature resistant organic material, such as polyimide (PI).

[0079] Figure 5A FIG. 4 is a schematic structural diagram of another exemplary mask 400 according to an embodiment of the present application.

[0080] like Figure 5AAs shown, the two opposite surfaces include a second surface 406. In some embodiments, a support structure 408 may be located on the second surface 406. The support structure 408 located on the second surface 406 may generate buoyancy to provide a support force along direction A for the edge region of the second mask 400. In some embodiments, the support structure 408 may include a buoyancy structure, which is configured to generate buoyancy in the direction in which the mask 400 provides a support force for the supported object to provide a support force to the supported object located at the location of the buoyancy structure, so that the edge region of the second mask 400 is attached to the substrate 106 to be evaporated.

[0081] Figure 5B A schematic diagram showing the distribution of an exemplary buoyancy structure in a limiting structure 410 according to an embodiment of the present application is shown.

[0082] like Figure 5B As shown, in some embodiments, the buoyancy structure may include a second airbag 502, the interior of the second airbag 502 may be connected, and the internally connected second airbag 502 may be filled with a gas with a density lower than a density threshold (eg, an inert gas such as helium).

[0083] Figure 5C An exemplary embodiment according to the present application is shown. Figure 5B FIG. 4 is a schematic cross-sectional view of the mask plate 400 obtained by cutting along the CC′ direction in FIG.

[0084] like Figure 5C As shown, the second airbag 502 filled with gas can generate buoyancy in the direction (eg, direction A) in which the mask 400 provides support force for the supported object, thereby making the edge area of ​​the second mask 400 fit with the substrate 106 to be evaporated.

[0085] Figure 6 FIG. 6 is a flow chart of a method 600 for preparing an exemplary mask according to an embodiment of the present application. The mask may be the mask 400 or the first mask 1022. The mask may include two opposite surfaces (eg, the first surface 404 and the second surface 406), such as Figure 6 As shown, the preparation method 600 may include the following steps.

[0086] In step 602, a plurality of first openings arranged in an array (eg, Figure 2 A plurality of first openings 210 in the embodiment of the present invention) and a support portion defining the plurality of first openings (eg, Figure 2 The support portion 402 in the middle includes a middle region (e.g., Figure 2 a middle region 4022) and an edge region located outside the middle region.

[0087] In step 604, a support structure (eg, Figure 4A The support structure 408 in the embodiment is located in the edge region. In this way, the support structure can support the second mask plate to be attached to the substrate to be evaporated along the direction A, so that the second mask plate can be effectively attached to the substrate to be evaporated, avoiding the generation of the edge gap of the second mask plate, and solving the edge color mixing problem of the evaporated substrate.

[0088] In some embodiments, at least one of the two opposite surfaces is provided with a limiting structure (for example, Figure 4A The limiting structure 410 is located in the edge region, and the supporting structure is arranged in the limiting structure in a one-to-one correspondence. The limiting structure can constrain the supporting structure and ensure that the supporting force of the supporting structure acts upward along direction A on the edge of the second mask.

[0089] In some embodiments, the shape of the limiting structure matches the shape of the first opening, and the limiting structure is arranged around each of the first openings located in the edge region, so that the support structure arranged in the limiting structure has a sufficiently large contact area with the edge of the second mask, so that the edge of the second mask can completely fit the substrate to be evaporated.

[0090] In some embodiments, the shape of the limiting structure is the same as that of the mask, and the limiting structure is arranged around a side of the plurality of first openings away from the middle region, so that the support structure in the limiting structure at the edge of the mask can also support the edge of the second mask.

[0091] In some embodiments, the two opposite sides include a first side (eg, Figure 4A The first surface 404 in the middle), the supporting structure is located on the first surface; the supporting structure includes a deformable structure and / or a magnetic structure;

[0092] Wherein, the deformable structure is configured to: generate deformation when heated and the deformation can provide a supporting force to the supported object located at the position of the deformation;

[0093] The magnetic structure is configured to move in a direction away from the mask under the action of an external magnetic field to provide a supporting force to the supported object located at the position of the magnetic structure. In this way, the supporting structure can exert a supporting force on the edge area of ​​the second mask toward the substrate to be evaporated, so that the edge area of ​​the second mask can be attached to the substrate to be evaporated, avoiding the generation of a gap in the edge area of ​​the second mask, and solving the problem of color mixing at the edge of the evaporated substrate.

[0094] In some embodiments, the deformable structure includes a first airbag (e.g., Figure 4D The first airbag 412 is filled with a heated expandable gas, and the first airbag filled with gas expands in a direction away from the mask when heated to protrude from the first surface, so that the edge area of ​​the second mask in contact with the first airbag can be attached to the substrate to be evaporated. And / or,

[0095] The deformable structure includes a ring structure made of nickel-titanium alloy (for example, Figure 4F The annular structure 414 in the embodiment of the present invention is deformable by heat, and the deformed annular structure includes at least one curved portion, and the curved portion protrudes from the first surface in a direction away from the mask, so that the edge area of ​​the second mask in contact with the curved portion can be attached to the substrate to be evaporated. And / or,

[0096] The magnetic structure (eg, Fig. 4I and Figure 4J The magnetic structure 418 in the embodiment includes a magnetic component (e.g., Fig. 4I and Figure 4J The magnetic component 4182 in the embodiment of the present invention) and the movable component connected to the magnetic component (for example, Fig. 4I and Figure 4J The movable component 4184 in the film has one end connected to the magnetic component, and the other end of the movable component is connected to the limiting structure to be fixed by the limiting structure. The magnetic component is supported by the movable component and moves in a direction away from the mask plate under the action of the external magnetic field to protrude from the first surface. In this way, the magnetic component protruding from the first surface can support the edge area of ​​the mask plate so that the edge area of ​​the mask plate fits with the substrate to be evaporated. And / or,

[0097] The magnetic structure (eg, Figure 4K and Figure 4L The magnetic structure 420 in the embodiment includes magnetic particles (e.g., Figure 4K and Figure 4L Magnetic particles 4202 in the packaging film (eg, Figure 4K and Figure 4L The packaging film 4204 in the first surface is covered with the packaging film, the packaging film covers the opening of the limiting structure, the magnetic particles are movably located in the limiting structure, and the magnetic particles lift the packaging film under the action of the magnetic field adsorption force to protrude from the first surface. The packaging film protruding from the first surface can lift the edge area of ​​the mask so that the edge area of ​​the mask fits with the substrate to be evaporated.

[0098] In some embodiments, the limiting structure includes an annular groove (for example, Figure 4HThe annular groove 416 in the annular groove is uniformly distributed with multiple annular structures, and the outer diameter of the annular structure matches the width of the annular groove; or the shape of the annular structure matches the shape of the annular groove and is arranged in the annular groove in a one-to-one correspondence. In this way, the support force provided by the curved parts of the multiple annular structures can make the edge area of ​​the second mask plate fit with the substrate to be evaporated.

[0099] In some embodiments, the two opposite sides include a second side (eg, Figure 5A The second surface 406 in the figure), the supporting structure is located on the second surface, the supporting structure includes a buoyancy structure, and the buoyancy structure is configured to: generate buoyancy in the direction in which the mask plate provides supporting force for the supported object to provide supporting force to the supported object located at the position of the buoyancy structure, so that the edge area of ​​the second mask plate is fitted with the substrate to be evaporated.

[0100] In some embodiments, the buoyancy structure includes a second airbag (for example, the second airbag 502), which is filled with a gas having a density lower than a density threshold. After being filled with gas, the second airbag generates buoyancy in the direction in which the mask provides supporting force for the supported object, thereby making the edge area of ​​the second mask fit with the substrate to be evaporated.

[0101] In some embodiments, the distance between the side of the limiting structure away from the middle area and the edge of the mask is greater than or equal to 100 microns, so as to prevent the limiting structure from being too close to the frame and being constrained by the clamps on the frame (for example, affected by the gravity of the clamps), thereby making it impossible for the supporting structure in the limiting structure to provide effective supporting force, so that the edge area of ​​the second mask cannot effectively fit the substrate to be evaporated.

[0102] The present application provides a mask plate and a preparation method thereof, a mask plate assembly, and an evaporation device. The mask plate includes a plurality of first openings arranged in an array and a support portion defining the plurality of first openings, and the support portion includes a central region and an edge region located outside the central region. The mask plate also includes two opposite surfaces, and a support structure located in the edge region is provided on at least one of the two opposite surfaces, so that the support structure provides a support force toward the substrate to be evaporated, so that the edge of the mask plate can be more closely attached to the substrate to be evaporated, thereby improving problems such as color mixing.

[0103] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present application (including the claims) is limited to these examples. In line with the concept of the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.

[0104] In addition, to simplify the description and discussion, and in order not to make the embodiments of the present application difficult to understand, the known power supply / ground connection with the integrated circuit (IC) chip and other components may or may not be shown in the provided drawings. In addition, the device can be shown in the form of a block diagram to avoid making the embodiments of the present application difficult to understand, and this also takes into account the fact that the details of the implementation of these block diagram devices are highly dependent on the platform to be implemented in the embodiments of the present application (that is, these details should be fully within the scope of understanding of those skilled in the art). In the case of elaborating specific details (e.g., circuits) to describe exemplary embodiments of the present application, it is obvious to those skilled in the art that the embodiments of the present application can be implemented without these specific details or when these specific details are changed. Therefore, these descriptions should be considered to be illustrative rather than restrictive.

[0105] Although the present application has been described in conjunction with specific embodiments of the present application, many replacements, modifications and variations of these embodiments will be apparent to those skilled in the art from the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may use the embodiments discussed.

[0106] The embodiments of the present application are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present application should be included in the scope of protection of the present application.

Claims

1. A mask plate, comprising a plurality of first openings arranged in an array and a support portion defining the plurality of first openings, the support portion comprising a central region and an edge region located at the periphery of the central region, the mask plate comprising two opposite surfaces, a support structure being provided on at least one of the two opposite surfaces, and the support structure being located at the edge region.

2. The mask according to claim 1, wherein: A limiting structure is provided on at least one of the two opposite surfaces, the limiting structure is located in the edge region, and the supporting structures are arranged in the limiting structure in a one-to-one correspondence.

3. The mask according to claim 2, wherein: The shape of the limiting structure is adapted to the shape of the first opening, and the limiting structure is arranged around each of the first openings located in the edge area.

4. The mask according to claim 2, wherein: The shape of the limiting structure is the same as that of the mask, and the limiting structure is arranged around a side of the plurality of first openings away from the middle area.

5. The mask according to claim 2, wherein: The two opposite surfaces include a first surface, and the supporting structure is located on the first surface; the supporting structure includes a deformable structure and / or a magnetic structure; Wherein, the deformable structure is configured to: generate deformation when heated and the deformation can provide a supporting force to the supported object located at the position of the deformation; The magnetic structure is configured to move in a direction away from the mask under the action of an external magnetic field to provide a supporting force to a supported object located at a position where the magnetic structure is located.

6. The mask according to claim 5, wherein: The deformable structure includes a first airbag, the first airbag is filled with a heated expandable gas, and the first airbag filled with gas expands in a direction away from the mask when heated to protrude from the first surface; and / or, The deformable structure comprises an annular structure made of nickel-titanium alloy, the annular structure is deformable when heated, the deformed annular structure comprises at least one curved portion, and the curved portion protrudes from the first surface in a direction away from the mask; and / or, The magnetic structure includes a magnetic component and a movable component connected to the magnetic component, one end of the movable component is connected to the magnetic component, and the other end of the movable component is connected to the limiting structure to be fixed by the limiting structure, and the magnetic component moves in a direction away from the mask under the support of the movable component and under the action of the external magnetic field to protrude from the first surface; and / or, The magnetic structure includes magnetic particles and a packaging film, the packaging film covers the opening of the limiting structure, the magnetic particles are movably located in the limiting structure, and the magnetic particles lift the packaging film under the action of magnetic field adsorption force to protrude from the first surface.

7. The mask according to claim 6, wherein: The limiting structure includes an annular groove whose shape is adapted to the first opening, and a plurality of the annular structures are evenly distributed in the annular groove, and the outer diameter of the annular structure is adapted to the width of the annular groove; or, the shape of the annular structure is adapted to the shape of the annular groove and is arranged in the annular groove in a one-to-one correspondence.

8. The mask according to claim 1, wherein: The two opposite surfaces include a second surface, the support structure is located on the second surface, the support structure includes a buoyancy structure, and the buoyancy structure is configured to generate buoyancy in the direction in which the mask provides support force for the supported object so as to provide support force to the supported object located at the position where the buoyancy structure is located.

9. The mask according to claim 8, wherein: The buoyancy structure includes a second airbag, which is filled with gas having a density lower than a density threshold. The second airbag filled with gas generates buoyancy in the direction in which the mask provides a supporting force for the supported object.

10. The mask according to claim 2, wherein: The distance between a side of the limiting structure away from the middle area and an edge of the mask is greater than or equal to 100 micrometers.

11. A mask assembly, comprising: A first mask, wherein the first mask is the mask according to any one of claims 1 to 10; A frame, the first mask is fixed on the frame, and the frame includes a first frame and a second frame opposite to each other; A plurality of second masks stacked on the first mask, the plurality of second masks are arranged in sequence along the direction in which the first frame and the second frame extend, and two ends of each of the second masks are fixed on the first frame and the second frame respectively; The supporting structure of the first mask provides supporting force for the edges of the plurality of second mask plates in a direction away from the first mask plate.

12. The mask assembly according to claim 11, wherein: The second mask includes a plurality of second openings and a shielding portion defining the plurality of second openings, and the plurality of second openings correspond one-to-one to the plurality of first openings of the first mask; The orthographic projection of the supporting structure of the first mask on the second mask is located on the shielding portion.

13. An evaporation device, comprising the mask assembly according to claim 11 or 12.

14. A method for preparing a mask, wherein the mask comprises two opposite sides, the method comprising: A plurality of first openings arranged in an array and a support portion defining the plurality of first openings, the support portion comprising a middle region and an edge region located at the periphery of the middle region; A supporting structure is provided on at least one of the two opposite surfaces, and the supporting structure is located in the edge region.

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