A magnetically resistant mask plate, a method for manufacturing the same, and a vapor deposition apparatus

Abstract

The application discloses an anti-magnetic mask plate and a preparation method and a vapor deposition device thereof, and belongs to the technical field of vapor deposition. The anti-magnetic mask plate comprises a single-layer or multi-layer composite film layer prepared from a low-thermal-expansion material and an anti-magnetic material, and pixel openings are uniformly arranged on a pixel area of the composite film layer. The anti-magnetic mask plate has the advantages of simple mask structure, low manufacturing cost, close adhesion to a substrate through the anti-magnetic effect, effective avoidance of sagging of the mask plate, and guaranteed quality of substrate evaporation.

Description

A diamagnetic mask, its preparation method, and a vapor deposition device Technical Field

[0001] This invention relates to the field of vapor deposition technology, and more particularly to an antimagnetic mask plate, its preparation method, and vapor deposition equipment. Background Technology

[0002] Vapor deposition technology includes various physical and chemical vapor deposition methods such as thermal evaporation vacuum vapor deposition, magnetron sputtering, molecular beam deposition, chemical vapor deposition, and atomic layer deposition. Mask vapor deposition involves placing a thin film or plate with a specific arrangement of holes on the substrate's film deposition surface during the vapor deposition process. This prevents film deposition in the areas blocked by the film or plate, while film is deposited in the areas with holes. This thin film or plate device, used to selectively deposit films on the substrate during the film deposition process, is generally called a mask or photomask.

[0003] For fine masks with very small patterns, the mask thickness must be very small to reduce via blockage and shadowing effects. This causes the mask to sag under gravity when placed above the vapor deposition equipment, creating a large gap between the mask and the substrate. This exacerbates the shadowing effect and reduces the quality of the deposited thin film pattern. Current methods to reduce sag often use very high-strength materials, but this approach is generally limited in effectiveness. Some methods involve plating thin films of ferromagnetic materials such as iron or nickel onto the mask surface. However, since the magnetic induction intensity at the mask is only 200-300 Gauss, the ferromagnetic materials lack sufficient magnetism to completely reduce sag; they can only mitigate the sag, not ensure complete contact between the mask and the substrate. Furthermore, during physical and chemical vapor deposition, the collisions and chemical reactions of the vapor phase materials with the substrate surface cause both the substrate and the mask to heat up. For masks requiring patterns smaller than 100 μm or even 1 μm and below, thermal expansion can cause deformation, further reducing the quality of the thin film pattern.

[0004] For example, patent CN111926291A discloses a photomask and a photomask assembly. The photomask includes an opening area and a welding area surrounding the opening area, with a blocking groove outside the opening area. When the photomask is welded to a frame, wrinkles will form on the photomask. This invention addresses this by providing a blocking groove on the photomask, which can prevent the transmission of wrinkles and avoid them from reaching the opening area of ​​the photomask, thereby preventing the opening area from shifting. This photomask solves the technical problem of reducing the risk of wrinkles during photomask welding to improve evaporation yield, but it still cannot solve the technical problems of photomask sagging due to gravity and deformation during evaporation. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides an antimagnetic mask, its preparation method, and a vapor deposition apparatus. The mask has a simple structure and low manufacturing cost. It can adhere tightly to the substrate through antimagnetic action, effectively preventing the mask from sagging and ensuring the quality of substrate evaporation.

[0006] To achieve the above objectives, the technical solution adopted by the present invention to solve its technical problem is: the antimagnetic mask includes a composite film layer with a single layer or multiple layers made of a low thermal expansion material and an antimagnetic material, and pixel openings are evenly distributed on the pixel area of ​​the composite film layer.

[0007] One side of the composite film layer is bonded to the support frame via an annular quartz sheet, and both the annular quartz sheet and the support frame are provided with clearance openings opposite to the pixel area.

[0008] The low thermal expansion material includes materials with a linear thermal expansion coefficient of less than 2 × 10⁻⁶. -6 / K is a glass material or polymer; the antimagnetic material includes graphite, graphene and mixtures thereof with clay, metal, polymer and small organic molecules.

[0009] The composite film layer includes a low thermal expansion film layer and an antimagnetic film layer disposed thereon. The low thermal expansion film layer is made of the low thermal expansion material, and the antimagnetic film layer is made of the antimagnetic material.

[0010] The thickness of the low thermal expansion film layer is 50-2000 nm, and the thickness of the antimagnetic film layer is 50-4000 nm.

[0011] The antimagnetic film layer is provided with staggered expansion joints, which divide the antimagnetic film layer into multiple regions, and each region is provided with a pixel opening.

[0012] The composite film is prepared by mixing the low thermal expansion material and the antimagnetic material, wherein the mass ratio of the low thermal expansion material to the antimagnetic material is 1:5 to 5:1.

[0013] A method for preparing the aforementioned antimagnetic mask includes the following steps:

[0014] Step 1: Prepare a composite film layer containing multiple pixel openings;

[0015] Step 2: Prepare a ring-shaped quartz sheet and bond the composite film layer to the support frame through the ring-shaped quartz sheet.

[0016] The preparation method in step 1 includes: 1) preparing an antimagnetic material; 2) depositing the antimagnetic material on a low thermal expansion film layer to form a composite film layer; 3) etching uniformly distributed pixel openings on the composite film layer;

[0017] Alternatively, the preparation method of step 1 may include: 1) preparing an imprinting positive plate; 2) preparing a mixed suspension of low thermal expansion material and antimagnetic material; 3) scraping the obtained mixed suspension onto a support plate to form a composite film layer, pressing the imprinting positive plate onto the composite film layer, and removing it after cooling.

[0018] A vapor deposition apparatus includes a deposition chamber, wherein a support stage and a molecular source are respectively disposed in the upper and lower parts of the deposition chamber, a Helmholtz coil is installed in the deposition chamber, an antimagnetic mask is positioned in the middle of the Helmholtz coil, a cooling plate is installed on the support stage, and a substrate is sandwiched between the antimagnetic mask and the cooling plate.

[0019] The beneficial effects of this invention are:

[0020] This invention utilizes a composite film layer with a single or multiple layers, constructed from low thermal expansion materials and antimagnetic materials. A pattern array of pixel openings with a specific shape is then created on this composite film layer, forming an antimagnetic mask. During operation, a Helmholtz coil is installed within the vapor deposition equipment. The mask, containing the substrate, is placed in the center of the Helmholtz coil. The antimagnetic material in the mask repels the magnetic field lines generated in the Helmholtz coil, creating a stable magnetic levitation phenomenon. This magnetic repulsion ensures the mask adheres tightly to the substrate, effectively preventing sagging. Furthermore, the low thermal expansion material in the mask minimizes deformation during the vapor deposition process, guaranteeing the quality of the substrate deposition. Attached Figure Description

[0021] The following is a brief explanation of the contents of each of the accompanying drawings and the markings in the drawings:

[0022] Figure 1 is a cross-sectional view of the antimagnetic mask plate of Embodiment 1 of the present invention;

[0023] Figure 2 is a top view of the antimagnetic mask plate of Embodiment 1 of the present invention;

[0024] Figure 3 is a cross-sectional view of the antimagnetic mask plate of Embodiment 2 of the present invention;

[0025] Figure 4 is a schematic diagram of the vapor deposition apparatus of the present invention;

[0026] The markings in the above figures are as follows: 1. Composite film layer, 1-1. Low thermal expansion film layer, 1-2. Antimagnetic film layer, 1-3. Expansion joint, 2. Pixel opening, 3. Annular quartz sheet, 4. Support frame, 5. Clearance opening, 6. Coating chamber, 7. Support stage, 8. Molecular source, 9. Helmholtz coil, 10. Cooling plate, 11. Substrate, 12. Positioning claw. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0028] In the description of this invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0029] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0030] In existing technologies, fine photomasks suffer from sagging and vapor deposition deformation. Therefore, based on these technical problems, this invention provides an electrostatic adsorption photomask, its preparation method, and a vapor deposition apparatus.

[0031] As shown in Figure 1, the present invention provides an antimagnetic mask, comprising a composite film layer 1 with a single-layer or multi-layer structure made of a low thermal expansion material and an antimagnetic material, wherein pixel openings 2 are evenly distributed on the pixel area of ​​the composite film layer 1. The low thermal expansion material comprises materials with a linear thermal expansion coefficient of less than 2 × 10⁻⁶. -6 / K refers to glass materials or polymers. The glass material can be low-thermal-expansion glass or ultra-low-thermal-expansion glass, such as silica glass, low-expansion titanium dioxide-doped silica glass, and low-expansion silicate glass. Among these, silica glass has a thermal expansion coefficient of 0.55 × 10⁻⁶. -6 / K; The polymer can be low-thermal-expansion polyimide, low-thermal-expansion polyaramid, low-thermal-expansion polycarbonate, etc. The above-mentioned low-thermal-expansion materials minimize the deformation of the mask during the vapor deposition process on the substrate 11, ensuring the quality of the vapor deposition. The antimagnetic materials include graphite (natural graphite, pyrolytic graphite), graphene, bismuth, etc., and mixtures thereof with clay, other metals, polymers, and small organic molecules. These substances repel the magnetic field lines of the Helmholtz coil 9, generating a stable magnetic levitation phenomenon. Through the magnetic repulsion, the mask can be kept close to the substrate 11, avoiding the phenomenon of the mask sagging due to gravity.

[0032] Specifically, the shape of the pixel opening 2 can be set to a circle, square, or irregular shape as needed, and the diameter or maximum side length of the pixel opening 2 is greater than 20nm and less than 100μm.

[0033] Specifically, one side of the composite film layer 1 is bonded to the support frame 4 by an annular quartz sheet 3 using adhesive. Both the annular quartz sheet 3 and the support frame 4 are provided with clearance openings 5 ​​opposite to the pixel area. The annular quartz sheet 3 and the support frame 4 provide effective support for the composite film layer 1. The clearance openings 5 ​​avoid blocking multiple pixel openings 2 in the pixel area, ensuring the smooth evaporation of the substrate 11.

[0034] Specifically, the composite film layer 1 includes two structures: one is a multilayer structure. Taking a two-layer structure as an example, this invention includes a low thermal expansion film layer 1-1 and an antimagnetic film layer 1-2 disposed thereon. The low thermal expansion film layer 1-1 is made of a low thermal expansion material, and the antimagnetic film layer 1-2 is made of an antimagnetic material. The low thermal expansion film layer 1-1 can also be configured as a multilayer low thermal expansion film layer 1-1 made of different materials, and the antimagnetic film layer 1-2 can also be configured as a multilayer antimagnetic film layer 1-2 made of different antimagnetic materials. The thickness of the low thermal expansion film layer 1-1 is 50-2000 nm, and the thickness of the antimagnetic film layer 1-2 is 50-4000 nm. The side of the composite film layer 1 closest to the antimagnetic film layer 1-2 is connected to the annular quartz sheet 3 by adhesive bonding. The antimagnetic film layer 1-2 is deposited on the surface of the low thermal expansion film layer 1-1, and the deposition method includes physical vapor deposition and chemical vapor deposition. As shown in Figure 2, specifically, the antimagnetic film layer 1-2 is provided with staggered expansion joints 1-3, which divide the antimagnetic film layer 1-2 into multiple regions, each region having a pixel opening 2. The expansion joints 1-3, through selective etching, separate the antimagnetic film layer 1-2 at each pixel opening 2, reducing the problem of thermal expansion between the antimagnetic film layer 1-2 and the low thermal expansion film layer 1-1 during mask operation, which could lead to wrinkles in the antimagnetic film layer 1-2 or even separation from the low thermal expansion film layer 1-1. Of course, for the low thermal expansion film layer 1-1, which inherently possesses a certain degree of flexibility, this separation problem caused by thermal expansion and contraction is usually nonexistent or minimal, and the expansion joints 1-3 may not be necessary.

[0035] Another type is a single-layer structure, as shown in Figure 3. In this structure, the composite film layer 1 is prepared by mixing a low-thermal-expansion material and an antimagnetic material, with a mass ratio of 1:5 to 5:1. The low-thermal-expansion material and the antimagnetic material are thermally mixed to form a solution, which can be prepared by coating or imprinting.

[0036] A method for preparing a diamagnetic mask includes the following steps:

[0037] Step 1: Prepare a composite film layer 1 containing multiple pixel openings 2. When the composite film layer 1 is a multilayer structure, its preparation method includes: 1) preparing an antimagnetic material: pyrolyzing the antimagnetic material or mixing the pyrolyzed antimagnetic material with a viscous material such as epoxy resin to obtain a mixed material; 2) depositing the antimagnetic material on a low thermal expansion film layer 1-1 to form a composite film layer 1: depositing the antimagnetic material on the surface of the low thermal expansion film layer 1-1 by coating; 3) etching (laser etching or chemical etching, etc.) uniformly distributed pixel openings 2 on the composite film layer 1. When the composite film layer is a single-layer structure, its preparation method includes: 1) preparing an imprinting positive plate; 2) preparing a mixed suspension of low thermal expansion material and antimagnetic material; 3) scraping the obtained mixed suspension onto a support plate to form a composite film layer 1, pressing it onto the composite film layer 1 with an imprinting positive plate, and removing it after cooling.

[0038] Step 2: Prepare the annular quartz sheet 3, and bond the composite film layer 1 to the support frame 4 through the annular quartz sheet 3.

[0039] As shown in Figure 4, the present invention also provides a vapor deposition apparatus, including a deposition chamber 6. A support stage 7 and a molecular source 8 are respectively disposed in the upper and lower parts of the deposition chamber 6. A Helmholtz coil 9 is installed inside the deposition chamber 6. The antimagnetic mask is positioned in the middle of the Helmholtz coil 9 by a positioning claw 12 within the deposition chamber 6. A cooling plate 10 for cooling the substrate 11 is installed on the support stage 7. The substrate 11 is held between the antimagnetic mask and the cooling plate 10. The Helmholtz coil 9 is generally composed of two or more parallel coil groups. The current flowing through the coil generates a relatively uniform magnetic field inside the coil. After the antimagnetic mask is placed between multiple coils, the antimagnetic material contained in the antimagnetic mask repels magnetic field lines, causing the antimagnetic mask to adhere tightly to the substrate 11, avoiding the problem of the mask sagging due to gravity.

[0040] The method of using the above-mentioned vapor deposition equipment includes the following steps:

[0041] Step 1: Place the substrate 11 on the antimagnetic mask, aligning the side of the substrate 11 to be deposited with the pixel opening 2 of the antimagnetic mask;

[0042] Step 2: Place the antimagnetic mask and substrate 11 in the middle of the Helmholtz coil 9;

[0043] Step 3: Position and fix the antimagnetic mask plate using the positioning claws 12, so that the antimagnetic mask plate and the cooling plate 10 clamp the substrate 11;

[0044] Step 4: When the Helmholtz coil 9 is energized, the antimagnetic mask contains antimagnetic material, which will repel magnetic field lines, causing the antimagnetic mask to adhere tightly to the surface of the substrate 11.

[0045] Step 5: Molecular source 8 inputs gas into coating chamber 6, and vapor deposition is completed on the surface of substrate 11 by physical or chemical vapor deposition.

[0046] The following examples will specifically illustrate the structure and preparation method of the two types of antimagnetic masks mentioned above.

[0047] Example 1

[0048] As shown in Figures 1 and 2, this embodiment provides an antimagnetic mask, including a low thermal expansion film layer 1-1 and an antimagnetic film layer 1-2. The low thermal expansion film layer 1-1 is low thermal expansion glass, and the antimagnetic film layer 1-2 is a mixture of graphite and epoxy resin. The antimagnetic film layer 1-2 is bonded to the support frame 4 through an annular quartz sheet 3.

[0049] The preparation method of the above-mentioned antimagnetic mask is as follows:

[0050] Step 1: Preparation of antimagnetic material: 50g of pyrolytic graphite was ball-milled in a mill for 2 hours to obtain pyrolytic graphite powder with an average particle size of 50nm. 50g of pyrolytic graphite powder was mixed with 50g of epoxy resin and stirred for 2 hours until uniformly mixed to obtain a pyrolytic graphite / adhesive mixture.

[0051] Step 2: Deposit antimagnetic material onto low thermal expansion film 1-1 to form composite film 1: Take a low thermal expansion glass film with a diameter of 300 mm and a thickness of 9 μm, whose linear thermal expansion coefficient is less than 10^-6 / K (purchased from Qinhuangdao Xingjian Special Glass Co., Ltd.), and uniformly coat its surface with a pyrolytic graphite / adhesive mixture with a thickness of about 1 μm using a spin coating process, and let it stand for 2 hours to allow it to fully cure.

[0052] Step 3: Etching uniformly distributed pixel openings 2 on the composite film layer 1: An array of holes with a specific pattern is fabricated in the composite film layer 1 using laser etching or chemical etching. The hole diameter is 2 μm, resulting in a fine antimagnetic composite mask sheet with open holes in the composite film layer 1. As needed, selective etching can be used to separate the pyrolytic graphite and epoxy resin composite layer in each pixel area, forming expansion joints 1-3, to reduce the thermal expansion of the graphite and epoxy resin composite layer during mask operation when the temperature rises.

[0053] Step 4: Prepare ring-shaped quartz sheet 3: Take a quartz glass sheet with a diameter of 300 mm and a thickness of 150 μm, and remove the circular part with a diameter of 250 mm centered on the center of the quartz sheet by laser cutting or diamond scribing, so as to make it into a ring-shaped quartz sheet 3.

[0054] Step 5: Bond the composite film layer 1 to the support frame 4 via the annular quartz sheet 3: 1) Lay the composite film layer 1 flat on a flat silicon wafer with a diameter of 300 mm, so that one side of the antimagnetic film layer 1-2 faces away from the silicon wafer; use screen printing to apply a 2 μm thick layer of epoxy resin adhesive to one side of the annular quartz sheet 3; then, place it horizontally on the surface of the composite film layer 1, with the adhesive-coated side facing the antimagnetic film layer 1-2 of the composite film layer 1; apply 10 N pressure to the quartz sheet and let it stand for 1 hour until the adhesive is completely cured.

[0055] 2) Apply a 2μm thick layer of epoxy resin adhesive to the side of the annular quartz sheet 3 facing away from the composite film layer 1. Then, place it horizontally into the groove of the stainless steel support frame 4 with the adhesive side facing the support frame 4. Apply 10N pressure to the quartz sheet and let it stand for 1 hour until the adhesive is completely cured.

[0056] Thus, in this embodiment, the composite film layer 1 containing a specific array of pores is bonded to the stainless steel support frame 4 by an annular quartz sheet 3, forming a fine mask template of low thermal expansion glass / strong antimagnetic pyrolytic graphite composite.

[0057] Example 2

[0058] As shown in Figure 3, this embodiment provides an antimagnetic mask plate, including a composite film layer 1 made of a mixture of a low thermal expansion material (polycarbonate) and an antimagnetic material (graphite). The composite film layer 1 is bonded to the support frame 4 through an annular quartz sheet 3.

[0059] 1) Prepare the printing plate; 2) Prepare a mixed suspension of low thermal expansion material and antimagnetic material; 3) Apply the obtained mixed suspension to the support plate to form a composite film layer 1, press the printing plate onto the composite film layer 1, and remove it after cooling.

[0060] The preparation method of the above-mentioned antimagnetic mask is as follows:

[0061] Step 1: Preparation of Imprint Positive Plate: 1) Take a quartz glass plate with a diameter of 300 mm, and deposit a copper layer with a thickness of 50 nm and a chromium layer with a thickness of 2 μm on its smooth surface by magnetron sputtering; use electron beam direct writing to create a specific pattern array of holes on its coating layer. The holes are circular, with a minimum size of 1 μm and a depth of 2 μm. This chromium-plated glass plate with specific holes becomes the master plate. 2) Spin-coat a 10 nm thick layer of dimethyl silicone oil onto the surface of the master plate as a release agent, and electrocast a 1 mm thick chromium plate on its surface. This chromium plate has protrusions that perfectly match the holes of the master plate. This chromium plate is called the imprint positive plate.

[0062] Step 2: Prepare a mixed suspension of low thermal expansion material and antimagnetic material: Place 50g of pyrolytic graphite in a mill and ball mill for 2 hours to obtain pyrolytic graphite powder with an average particle size of 50nm; mix 50g of pyrolytic graphite powder with 50g of polycarbonate particles, heat to 290℃ in a nitrogen atmosphere, and stir for 2 hours after the polycarbonate is completely melted to make the graphite powder and polycarbonate uniformly mixed to obtain a pyrolytic graphite / polycarbonate composite material suspension.

[0063] Step 3: Preparation of composite film layer 1 containing multiple pixel openings 2: Spray dimethyl silicone oil with a thickness of 20nm onto the clean stainless steel anvil and the surface of the imprinting positive plate as a release agent; take 10g of molten pyrolytic graphite / polycarbonate composite material suspension and scrape it onto the stainless steel anvil, then press the imprinting positive plate onto the composite film, apply a force of 10kg, maintain for 2 minutes, and remove the composite film after it has completely cooled. This results in a pyrolytic graphite / polycarbonate composite film with a thickness of 2μm and containing a pattern array with a minimum size of 1μm. This film is the composite film layer 1 of the pyrolytic graphite / polycarbonate composite material.

[0064] Step 4: Following the methods in steps 4 and 5 of Example 1, fix the composite film layer 1 to the support frame 4 via the annular quartz sheet 3.

[0065] Thus, in this embodiment, the composite film layer 1 containing a specific array of pores is bonded to the stainless steel support frame 4 by an annular quartz sheet 3, forming a fine mask template of pyrolytic graphite / polycarbonate composite.

[0066] In summary, the mask designed in this invention has a simple structure and low manufacturing cost. It can adhere tightly to the substrate through antimagnetic properties, effectively preventing the mask from sagging and ensuring the quality of substrate evaporation.

[0067] The above description is merely an illustration of some principles of the present invention. This specification is not intended to limit the present invention to the specific structures and applicable scope shown. Therefore, all possible modifications and equivalents that may be used fall within the scope of the patent application of this invention.

Claims

1. A diamagnetic mask, characterized in that, This includes a composite film layer with a single-layer or multi-layer structure made of a low thermal expansion material and a diamagnetic material, wherein pixel openings are evenly distributed on the pixel area of ​​the composite film layer; the low thermal expansion material includes materials with a linear thermal expansion coefficient of less than 2 × 10⁻⁶. -6 / K is a glass material or polymer; the antimagnetic material includes graphite, graphene and mixtures thereof with clay, metal, polymer and small organic molecules.

2. The antimagnetic mask according to claim 1, characterized in that: One side of the composite film layer is bonded to the support frame via an annular quartz sheet, and both the annular quartz sheet and the support frame are provided with clearance openings opposite to the pixel area.

3. The antimagnetic mask according to claim 1, characterized in that: The composite film layer includes a low thermal expansion film layer and an antimagnetic film layer disposed thereon. The low thermal expansion film layer is made of the low thermal expansion material, and the antimagnetic film layer is made of the antimagnetic material.

4. The antimagnetic mask plate according to claim 3, characterized in that: The thickness of the low thermal expansion film layer is 50-2000 nm, and the thickness of the antimagnetic film layer is 50-4000 nm.

5. The antimagnetic mask plate according to claim 3, characterized in that: The antimagnetic film layer is provided with staggered expansion joints, which divide the antimagnetic film layer into multiple regions, and each region is provided with a pixel opening.

6. The antimagnetic mask according to claim 1, characterized in that: The composite film is prepared by mixing the low thermal expansion material and the antimagnetic material, wherein the mass ratio of the low thermal expansion material to the antimagnetic material is 1:5 to 5:

1.

7. A method for preparing a diamagnetic mask as described in any one of claims 1 to 6, characterized in that, The process includes the following steps: Step 1: Prepare a composite film layer containing multiple pixel openings; Step 2: Prepare an annular quartz sheet and bond the composite film layer to the support frame via the annular quartz sheet.

8. The method for preparing the antimagnetic mask according to claim 7, characterized in that: The preparation method of step 1 includes: 1) preparing an antimagnetic material; 2) depositing the antimagnetic material on a low thermal expansion film layer to form a composite film layer; 3) etching uniformly distributed pixel openings on the composite film layer; or the preparation method of step 1 includes: 1) preparing an imprinting positive plate; 2) preparing a mixed suspension of low thermal expansion material and antimagnetic material; 3) scraping the obtained mixed suspension onto a support plate to form a composite film layer, pressing the imprinting positive plate onto the composite film layer, and removing it after cooling.

Images