A device and method for uniform glue application

Abstract

The application relates to the mask manufacturing field, in particular to a device and method for uniform glue coating, the device comprising a bearing component, the bearing component comprising a bearing table for bearing the mask and a driving mechanism for driving the bearing table to rotate and lift; the bearing table is circular and provided with a rectangular recessed area in the middle; the bearing table is provided with four openings for separating the circumference of the bearing table, each opening corresponding to one of the four corners of the recessed area and being in communication with the recessed area to form a flow channel. The circular bearing table provided with the square recessed area is used to compensate the upper surface of the square mask to be circular through the bearing table, so that the photoresist is prevented from being accumulated at the right-angle edges of the mask during spraying; and the flow channel formed by the openings arranged at the four corners of the recessed area can change the wind flow direction of the upper part of the mask, so that the photoresist is driven to flow to the edge corners of the square mask along the diagonal direction, and the problem of uneven glue coating at the edges of the square mask is effectively solved.

Description

Technical Field

[0001] This application relates to the field of photomask manufacturing technology, and more specifically to an apparatus and method for uniformly applying adhesive. Background Technology

[0002] In the semiconductor manufacturing field, photolithography is the core process for pattern transfer. As a key consumable in the photolithography process, the quality of the photoresist coating on the photomask surface directly affects the pattern accuracy and yield. With the rapid development of display panels, advanced packaging, and other technologies, the application of square photomasks is becoming increasingly widespread, placing extremely high demands on the uniformity of the photoresist coating on their surface.

[0003] However, during the outward diffusion of photoresist on the surface of a square photomask, the uniformity of its film edge is more difficult to control than that of a circular photomask. In particular, the four corner areas of a square photomask are more prone to photoresist accumulation or lack of isochromatic patterns, resulting in uneven coating (mura) defects, which seriously restricts the improvement of product yield.

[0004] Therefore, there is an urgent need for a device and method that can uniformly apply adhesive to square photomasks to solve the problem of uneven adhesive application at the edges. Summary of the Invention

[0005] The technical problem to be solved by this application is to provide an apparatus and method for uniformly applying adhesive, so as to solve the problem of uneven adhesive application at the edges.

[0006] According to a first aspect of the embodiments of this application, an apparatus for uniformly applying adhesive is provided, including an adhesive application chamber and the following components disposed within the adhesive application chamber:

[0007] The support component includes a support platform for supporting the mask and a drive mechanism for driving the support platform to rotate and lift. The support platform is circular and has a rectangular recessed area in the middle. The support platform has four openings that divide the circumference of the support platform. Each opening corresponds to one of the four corners of the recessed area and communicates with the inside of the recessed area to form a drainage channel. A photoresist spraying component is disposed above the supporting component and is used to spray photoresist onto the surface of the photomask. A splash-proof component for accommodating the support component, wherein the top of the splash-proof component is provided with a first central through hole, and the support platform is located below the first central through hole; A lifting cover plate includes an annular cover plate and a lifting mechanism connected to the annular cover plate; the annular cover plate covers the first central through hole to compress the upper space of the edge of the mask plate; The exhaust component is connected to the bottom of the splash guard component.

[0008] In one embodiment, the splash-proof component includes a bottom cup, a middle cup, a flat cup, and an upper cup that are coaxially arranged layer by layer from bottom to top. The exhaust component is connected to the bottom cup, and the bottom cup has a waste liquid collection tank. The middle cup, the flat cup, and the upper cup are all inverted cup-shaped structures, and a third central through hole, a second central through hole, and a first central through hole are respectively provided in the middle part of the bottom of the middle cup, the flat cup, and the upper cup. The supporting component is provided by the bottom cup passing through the third and second central through holes, so that the supporting platform is located above the middle cup and can move up and down between the flat cup and the upper cup.

[0009] In one embodiment, the flat cup includes a cylindrical flat cup outer wall and a first drainage portion disposed within the flat cup outer wall. The first drainage portion has an upwardly protruding spherical structure, and a second central through hole is located at the center of the first drainage portion. The connection between the first drainage portion and the outer wall is provided with a plurality of vertically penetrating first waste liquid holes.

[0010] In one embodiment, the middle cup has a columnar middle cup sidewall and a frustum-shaped bottom surface protruding towards the flat cup. One end of the frustum-shaped bottom surface is a large circle connected to the middle cup sidewall, and the other end is a small circle. The center of the small circle end face is provided with the third central through hole. The end of the frustum-shaped bottom surface near the large circle is provided with a plurality of second waste liquid holes that penetrate vertically.

[0011] In one embodiment, the annular cover plate includes a stepped first annular plate and a second annular plate, the second annular plate being disposed inside the first annular plate and lower than the first annular plate. When the annular cover plate covers the first central through hole, the second annular plate extends into the interior of the splash-proof component to compress the upper space of the mask edge.

[0012] In one embodiment, the inner circle dimension of the annular cover plate is the same as the inscribed circle dimension of the mask.

[0013] In one embodiment, the bottom surface of the recessed area is provided with a plurality of support anti-slip points for supporting the mask plate.

[0014] In one embodiment, the bottom surface of the recessed area is further provided with a plurality of cleaning holes, which are connected to an external cleaning liquid source through pipelines.

[0015] In one embodiment, the diameter of the support stage is the same as the diameter of the circumcircle of the mask.

[0016] According to a second aspect of the embodiments of this application, a method for uniformly applying adhesive is provided, applicable to the aforementioned apparatus for uniformly applying adhesive, comprising the following steps: Raise the annular cover plate, control the support platform to rise to the loading position, and place the mask in the recessed area of ​​the support platform; The support platform is controlled to descend to the process position, the annular cover plate descends to cover the first central through hole on the top of the splash-proof component, and the exhaust component is activated to exhaust air from the inside of the splash-proof component; The adhesive spraying component is controlled to spray photoresist onto the surface of the photomask, while the support stage is controlled to rotate sequentially at a first speed and a second speed to spread the photoresist; wherein the second speed is greater than the first speed. The support stage is controlled to rotate at a step-down speed in response to the end of the photoresist spraying until the support stage stops rotating.

[0017] In one embodiment, when the uniform adhesive application device includes supporting anti-slip points and cleaning holes, the control platform rotates at a step-down speed while simultaneously spraying cleaning fluid from the cleaning holes onto the bottom surface of the mask.

[0018] In one embodiment, the method for uniformly applying photoresist further includes spraying a photoresist thinner onto the top surface of the photomask before the photoresist spraying component sprays photoresist onto the surface of the photomask.

[0019] Compared with the prior art, the beneficial effects of this application are as follows: (1) This application uses a circular support platform with a square recessed area. The support platform compensates the upper surface of the square mask to be circular, so that its edge is smoothly transitioned, avoiding obvious edge accumulation of photoresist at the right angle of the mask during spraying; and the openings set at the four corners of the recessed area form a drainage channel that can change the airflow direction of the upper part of the mask, so that the photoresist flows along the diagonal direction to the corners of the square mask under the drive of the airflow, reducing the probability of uneven coating at the four corners of the mask; (2) This application reduces the eddies, turbulence and airflow disturbances generated by the airflow at the edge and four corners of the mask during the photoresist spraying and drying process by compressing the space above the edge of the mask with an annular cover plate. This makes the airflow field more stable and uniform, thereby reducing defects such as uneven photoresist film thickness, edge accumulation or local overthinness caused by airflow turbulence. At the same time, after the annular cover plate compresses the edge space, the effective flow area of ​​the edge area is reduced under the same air supply flow rate, which makes the airflow velocity at the edge correspondingly increase, strengthens the airflow purging and drying effect of the edge area, and further promotes the photoresist to flow fully and spread evenly to the four corners and outer edge areas of the mask under the combined action of centrifugal force and airflow. (3) This application adopts a four-layer, mutually cooperating, surrounding anti-splash cup structure, which can perform layered constraint and directional guidance of airflow and liquid in the anti-splash component, effectively avoiding the formation of eddies, turbulence and dead zones in the airflow at the edge of the mask and the corner of the cavity, and significantly reducing airflow disturbance. At the same time, the gas-liquid separation design using a flat cup can effectively separate the gas phase and liquid phase in time during the airflow process, preventing the atomized photoresist from impacting and rebounding onto the mask surface with the airflow, reducing the generation of surface defects such as backsplash and particle residue, thereby improving the uniformity of photoresist film formation; (4) This application provides multiple support anti-slip points and multiple cleaning holes on the bottom surface of the recessed area. The cleaning liquid is sprayed into the space between the bottom of the mask and the bottom surface of the recessed area through the cleaning holes to fully rinse the dead corner areas deposited on the back of the mask that are difficult to reach, effectively removing residual photoresist, solvent, particles and other contaminants, and avoiding long-term adhesion of contaminants that may cause pollution diffusion or scratch the mask. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of an apparatus for uniformly applying adhesive according to an exemplary embodiment; Figure 2 This is a structural schematic diagram of the load-bearing component; Figure 3 This is a horizontal projection of the support platform; Figure 4 This is an explosion diagram of the splash guard components; Figure 5 This is a schematic diagram comparing the uniformity of the adhesive coating on the photomasks obtained in Example 1 and Comparative Example 1. Figure 6 This is a schematic diagram comparing the uniformity of adhesive coating on the photomasks obtained in Example 2 and Comparative Example 2.

[0021] The meanings of the reference numerals in the attached figures are as follows: 1. Supporting component; 11. Supporting platform; 12. Drive mechanism; 110. Recessed area; 111. Cleaning hole; 112. Opening; 2. Anti-splash component; 21. Upper cup; 22. Flat cup; 221. Outer wall of flat cup; 222. First drainage part; 23. Middle cup; 231. Side wall of middle cup; 232. Spherical bottom surface; 24. Bottom cup; 3. Mask plate; 4. Lifting cover plate; 41. First ring plate; 42. Second ring plate. Detailed Implementation

[0022] Unless otherwise defined, the technical or scientific terms used in this specification and claims shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. Specific embodiments of this application will be described below in conjunction with the accompanying drawings. It should be noted that, in order to provide a concise description, this specification cannot exhaustively describe all features of the actual embodiments. Without departing from the spirit and scope of this application, those skilled in the art can modify and substitute the embodiments of this application, and the resulting embodiments are also within the protection scope of this application.

[0023] To address the problems existing in the prior art, this application provides an apparatus and method for uniform adhesive application to solve the problem of uneven adhesive application at the edges.

[0024] Firstly, such as Figures 1-4 As shown, in one specific embodiment, an apparatus for uniformly applying adhesive is provided, including an adhesive application chamber and the following components disposed within the adhesive application chamber: The support component 1 includes a support platform 11 for supporting the mask 3 and a drive mechanism 12 for driving the support platform 11 to rotate and lift. The support platform 11 is circular and has a rectangular recessed area 110 in the center. The support platform 11 has four openings 112 that divide the circumference of the support platform 11. Each opening 112 corresponds to one of the four corners of the recessed area 110 and communicates with the inside of the recessed area 110 to form a drainage channel. The projection of the support platform 11 on the horizontal plane is as follows: Figure 3 As shown, the drainage channel is as follows: Figure 3 As indicated by the dashed arrow; The adhesive spraying component is located above the support component 1 and is used to spray photoresist onto the surface of the mask 3. The splash-proof component 2 is used to accommodate the support component 1. The top of the splash-proof component 2 is provided with a first central through hole, and the support platform 11 is located below the first central through hole. The lifting cover plate 4 includes an annular cover plate and a lifting mechanism connected to the annular cover plate; the annular cover plate covers the first central through hole to compress the upper space of the support platform 11 and the edge of the mask plate 3. The exhaust component is connected to the bottom of the splash guard component 2.

[0025] In this embodiment, the photomask 3 is placed on the support platform 11 with the recessed area 110. The upper surface of the square photomask 11 is compensated into a circle by the support platform 11 to avoid obvious edge accumulation of photoresist at the right angles of the photomask 3 during spraying. Furthermore, by setting the openings 112 at the four corners of the recessed area 110, a flow channel is formed to change the airflow direction, so that the photoresist flows along the diagonal direction of the photomask 3 to the corners of the square photomask 3 under the drive of the airflow, making the photoresist coating at the four corners of the square photomask 3 more uniform.

[0026] Combination Figure 1 , Figure 4 As shown, in one specific embodiment, the splash-proof component 2 includes a bottom cup 24, a middle cup 23, a flat cup 22, and an upper cup 21, which are coaxially arranged from bottom to top. The exhaust component is connected to the bottom cup 24, and the bottom cup 24 has a waste liquid collection tank. The middle cup 23, the flat cup 22, and the upper cup 21 are all inverted cup-shaped structures, and a third central through hole, a second central through hole, and a first central through hole are respectively provided in the middle part of the bottom of the middle cup 23, the flat cup 22, and the upper cup 21. The supporting component 1 is provided by the bottom cup passing through the third and second central through holes, so that the supporting platform 11 is located above the middle cup 23 and can move up and down between the flat cup 22 and the upper cup 21.

[0027] In this embodiment, the upper cup 21 is used to support the annular cover plate to compress the upper space at the edge of the photomask 3; the flat cup 22 is flush with or slightly higher than the support platform 11 and is used to separate the misty photoresist, solvent vapor and purge airflow generated during the spraying process; the middle cup 23 is located below the flat cup 22 and is used to guide and drain the separated waste liquid; the bottom cup 24 is located at the bottom and serves two purposes: firstly, to connect to the external exhaust system to form a stable main airflow path, and secondly, to collect the waste liquid for subsequent centralized discharge. Using the above-mentioned anti-splash component 2 can effectively constrain and directionally guide the airflow and liquid within the anti-splash component 2, thereby preventing the formation of eddies, turbulence and dead zones at the edge of the photomask 3 and the corners of the cavity, significantly reducing airflow disturbance. At the same time, the gas phase and liquid phase can be effectively separated in time during the airflow process, preventing the atomized photoresist from impacting and rebounding onto the surface of the mask 3 with the airflow, reducing the generation of surface defects such as splashing and particle residue, thereby improving the quality of photoresist film formation and avoiding uneven coating of photoresist at the four corners or edges of the mask 3.

[0028] Combination Figure 1 , Figure 4 As shown, in one specific embodiment, the flat cup 22 includes a cylindrical flat cup outer wall 221 and a first drainage part 222 disposed inside the flat cup outer wall 221. The first drainage part 222 has an upwardly protruding spherical structure, and the second central through hole is located at the center of the first drainage part 222. The connection between the first drainage part 222 and the outer wall is provided with a plurality of first waste liquid holes (not shown in the figure) that penetrate vertically.

[0029] When the support stage 11 drives the photomask 3 to rotate at high speed, excess photoresist is thrown away from the edge of the photomask 3 under centrifugal force, forming a mixed liquid containing fine droplets and mist. As the airflow moves, when it reaches the arc-shaped first guide section 222, due to the centrifugal force field and airflow carrying, the liquid moves along the arc shape of the side of the first guide section 222, which can collect the droplets on its surface and guide them downward by gravity, eventually converging at the bottom and flowing into the lower middle cup 23 through the first waste liquid hole. The gas, with a much lower density, will continue to move inward or upward when it encounters the arc structure and turns, separating from the liquid. This embodiment achieves gas-liquid separation by setting the spherical first guide section 222, avoiding the atomized droplets from being turned back and raised by the airflow and re-attached to the surface of the photomask 3, thereby fundamentally reducing defects such as splashing and uneven film thickness.

[0030] Combination Figure 1 , Figure 4 As shown, in one specific embodiment, the middle cup 23 has a columnar middle cup sidewall 231 and a frustum-shaped bottom surface 232 protruding towards the flat cup 22. One end of the frustum-shaped bottom surface 232 is a large circle connected to the middle cup sidewall 231, and the other end is a small circle. A third central through hole is opened at the center of the small circle end face. A plurality of second waste liquid holes (not shown in the figure) are provided at the end of the frustum-shaped bottom surface 232 near the large circle. Specifically, 2-10 second waste liquid holes can be provided according to process requirements, preferably 2-6; and the number of second waste liquid holes is less than the number of first waste liquid holes.

[0031] In this embodiment, the middle cup 23 is located below the flat cup 22. The separated waste liquid is guided and diverted through the spherical bottom surface 232, so that the waste liquid flows along the arc-shaped side of the spherical bottom surface 232 to the second waste liquid hole at its edge, and flows into the bottom cup 24 through the second waste liquid hole, which facilitates the subsequent centralized discharge of waste liquid.

[0032] like Figure 1 As shown, in one specific embodiment, the annular cover plate includes a stepped first annular plate 41 and a second annular plate 42. The second annular plate 42 is disposed inside the first annular plate 41 and is lower than the first annular plate 41. When the annular cover plate covers the first central through hole, the second annular plate 42 extends into the interior of the splash guard 2 to compress the upper space of the edge of the support platform 11 and the mask 3. Preferably, the distance between the lower surface of the second annular plate and the upper surface of the mask is in the range of 8mm-50mm.

[0033] In this embodiment, by compressing the space above the edge of the photomask 3 using an annular cover plate, the eddies, turbulence, and airflow disturbances generated by the airflow at the edge and corners of the photomask 3 during photoresist spraying and drying are reduced. This makes the airflow field more stable and uniform, thereby reducing defects such as uneven photoresist film thickness, edge accumulation, or localized excessive thinness caused by airflow turbulence. Simultaneously, after the annular cover plate compresses the edge space, the effective flow area at the edge decreases under the same air supply flow rate, resulting in a corresponding increase in airflow velocity at the edge. This strengthens the airflow purging and drying effect at the edge, further promoting the photoresist to flow fully and spread evenly to the corners and outer edge areas of the photomask 3 under the combined action of centrifugal force and airflow.

[0034] like Figure 1 As shown, in one specific embodiment, the inner circle size of the annular cover plate is the same as the inscribed circle size of the mask plate 3.

[0035] Because the inner circle of the annular cover plate matches the inscribed circle of the photomask 3, the width of the airflow gap formed by the annular cover plate around the photomask 3 is equal everywhere. This avoids excessively high or low local wind speeds caused by uneven gaps, resulting in a more uniform and symmetrical airflow distribution at the edges and effectively suppressing the generation of eddies, turbulence, and airflow disturbances at the four corners. Simultaneously, this dimensional matching relationship ensures consistent flow resistance and uniform spreading speed of the photoresist towards the four corners and edges of the photomask 3 during spraying and drying. This further balances the photoresist drying speed between the central and corner areas of the photomask 3 surface, improving film thickness uniformity and surface smoothness.

[0036] Combination Figure 2 As shown, in one specific embodiment, the bottom surface of the recessed area 110 is provided with a plurality of support anti-slip points (not shown in the figure) for supporting the mask plate 3.

[0037] In this embodiment, the mask plate 3 is supported by multiple anti-slip support points. On the one hand, this can reduce the contact area and reduce the possible contamination and damage to the back of the mask plate 3. On the other hand, the point support leaves a small gap or channel between the mask plate 3 and the bottom surface of the recessed area 110, which facilitates airflow and waste discharge.

[0038] In some embodiments, the anti-slip support points may be made of rubber, polyurethane, or a material with a high coefficient of friction, or have knurled or raised textures on their tops to increase the coefficient of friction of the contact surface and improve the stability of the positioning support.

[0039] Combination Figure 2 As shown, in one specific embodiment, the bottom surface of the recessed area 110 is also provided with a plurality of cleaning holes 111, which are connected to an external cleaning liquid source through pipelines.

[0040] Specifically, the cleaning hole can be set with one or more rings of cleaning holes centered on the axis of the support platform, which is not limited here.

[0041] In this embodiment, cleaning fluid is sprayed into the space between the bottom of the mask 3 and the bottom surface of the recessed area 110 through the cleaning hole 111 to thoroughly rinse the hard-to-reach dead corner areas deposited on the back of the mask 3, effectively removing residual photoresist, solvent, particles and other contaminants, and avoiding long-term adhesion of contaminants that could cause pollution diffusion or scratch the mask 3.

[0042] like Figure 1 As shown, in one specific embodiment, the diameter of the support platform 11 is the same as the diameter of the outer circle of the mask 3, and the size of the recessed area 110 is the same as the size of the mask 3.

[0043] In this embodiment, when the photomask 3 is placed in the recessed area 110 in the middle of the support platform 11, the outer edges of the four corners of the photomask 3 are aligned with the outer edges of the support platform 11, with uniform circumferential positioning and stable fit. This avoids edge suspension due to excessively large diameter of the support platform 11 or insufficient support due to excessively small diameter. During the spraying and drying process, this dimensional matching relationship allows the lower support surface of the photomask 3 and the upper annular cover plate to form symmetrical airflow channels with uniform gaps, ensuring consistent airflow around the photomask 3 and in the four corner areas. This effectively avoids local airflow turbulence, turbulence, and edge effects caused by mismatched support surface dimensions. At the same time, this structure allows the photomask 3 to be accurately positioned and placed stably on the support platform 11, reducing uneven film thickness caused by offset or shaking. This further ensures uniform flow, spreading, and drying speed of the photoresist on the surface of the photomask 3, improving film consistency and process stability.

[0044] like Figures 1-4 As shown, according to a second aspect of the embodiments of this application, a method for uniformly applying adhesive is provided, applicable to the aforementioned apparatus for uniformly applying adhesive, comprising the following steps: Raise the annular cover plate, control the support platform 11 to rise to the loading position, and place the mask plate 3 in the recessed area 110 of the support platform 11; The control platform 11 is lowered to the process position, the annular cover plate is lowered to cover the first central through hole on the top of the splash-proof component 2, and the exhaust component is activated to exhaust the air inside the splash-proof component 2. The adhesive spraying component sprays photoresist onto the surface of the mask 3, while the support stage 11 rotates sequentially at a first speed and a second speed to spread the photoresist; wherein the second speed is greater than the first speed. The control stage 11 rotates at a step-down speed in response to the end of the photoresist spraying until the stage 11 stops rotating.

[0045] In this embodiment, the upper surface of the square photomask 3 is compensated to be circular by the support stage 11, avoiding obvious edge accumulation of photoresist at the right angles of the photomask 3 during spraying. Furthermore, the openings 112 at the four corners of the recessed area 110 form drainage channels that change the airflow direction at the top of the photomask 3, allowing the photoresist to flow diagonally to the corners of the square photomask 3 under the influence of the airflow, reducing the probability of uneven coating at the corners of the photomask 3. Simultaneously, the support stage 11 sprays and spreads the photoresist in a segmented rotational manner, first at a lower first speed and then at a higher second speed. This allows the photoresist to be fully and evenly spread on the surface of the photomask 3 before being gradually centrifugally flattened. This ensures that the photoresist has sufficient time to cover the entire surface of the photomask 3, avoiding localized missing photoresist, streaks, or thickness differences, while also forming a uniform and smooth photoresist film through a higher rotational speed. After spraying, the control platform 11 gradually decelerates to a stop in a stepped manner, which avoids drastic changes in centrifugal force caused by sudden changes in rotation speed. This effectively prevents defects such as uneven film thickness, edge accumulation, and ripples caused by inertial impact, local backflow, or edge springback of the photoresist. The photoresist layer is further stabilized and leveled during the deceleration process, resulting in a photoresist coating with higher uniformity, smoother surface, and more regular edge contours, which significantly improves film quality and process stability.

[0046] Combination Figures 1-4 As shown, in one specific embodiment, when the device for uniformly applying adhesive includes a support anti-slip point and a cleaning hole 111, while controlling the support platform 11 to rotate at a step-down speed, cleaning liquid is simultaneously sprayed from the cleaning hole 111 onto the bottom surface of the mask 32.

[0047] In this embodiment, cleaning fluid is sprayed into the space between the bottom of the mask 3 and the bottom surface of the recessed area 110 through the cleaning hole 111 to clean contaminants on the back of the mask 3, reduce defects in subsequent processes, and improve product yield and service life of the mask 3.

[0048] Combination Figures 1-4As shown, in one specific embodiment, the driving device 12 drives the support platform 11 to rotate at a first speed for a first time; then the driving device drives the support platform to rotate at a second speed for a second time; the rotation of the support platform 11 at a step-down speed includes: the support platform continuously rotating at a third speed for a third time, then continuously rotating at a fourth speed for a fourth time, and finally continuously rotating at a fifth speed for a fifth time. The first speed range is 0 rpm-500 rpm, and the first time range is 1 s-10 s; the second speed range is 1 rpm-5000 rpm, and the second time range is 1 s-20 s; the third speed range is 1 rpm-3000 rpm, and the third time range is 1 s-10 s; the fourth speed range is 1 rpm-1500 rpm, and the fourth time range is 1 s-30 s; the fifth speed range is 1 rpm-1500 rpm, and the fifth time range is 10 s-100 s. While the drive unit 12 drives the support platform 11 to rotate continuously at the fourth speed for the fourth time, the cleaning component is activated, and the cleaning component sprays cleaning fluid from the cleaning hole 111 to the bottom surface of the mask plate 3.

[0049] In this embodiment, the support stage 11 descends in three steps, gradually reducing its rotational speed until it stops. This avoids drastic changes in centrifugal force caused by sudden changes in rotational speed, effectively preventing defects such as uneven film thickness, edge buildup, and ripples caused by inertial impact, local backflow, or edge springback of the photoresist. The photoresist layer becomes more stable and leveled during deceleration, ultimately resulting in a photoresist coating with higher uniformity, a smoother surface, and more regular edge contours, significantly improving film quality and process stability. Simultaneously, while rotating at the stepped descent speed, cleaning fluid is sprayed from the self-cleaning hole 111 onto the bottom surface of the mask 32 to clean contaminants on the back of the mask 3, reducing subsequent process defects and improving product yield and the lifespan of the mask 3.

[0050] In one specific embodiment, the method of uniformly applying photoresist further includes: spraying a photoresist thinner onto the top surface of the photomask before the photoresist spraying component sprays the photoresist onto the surface of the photomask.

[0051] In this embodiment, the photoresist thinner is sprayed onto the top surface of the mask in advance, which not only increases the humidity inside the cavity, but also wets the surface of the mask to increase the surface fluidity for subsequent photoresist coating, improves the spreadability and wettability of the photoresist on the mask surface, and makes it cover the entire surface more evenly and quickly, avoiding defects such as local non-wetting, pinholes, streaks or uneven film thickness.

[0052] In one specific embodiment, when spraying photoresist or photoresist diluent, either center-point spraying or radial moving spraying can be selected according to process requirements; there is no limitation here.

[0053] Among them, the center-point spraying means that the adhesive spraying component is kept at the center of the inscribed circle of the mask for spraying; the radial moving spraying means that along the radial direction of the support platform, the adhesive spraying component moves from the center of the inscribed circle of the mask to the edge of the inscribed circle of the mask, or from the edge of the inscribed circle of the mask to the center of the inscribed circle of the mask, and sprays while moving radially.

[0054] By flexibly selecting between fixed-point and radial moving sprays, it can adapt to photoresist and solvent processes with different viscosities, different evaporation rates, and different film thickness requirements, improving the equipment's versatility and process adjustability. This results in more uniform spread of photoresist on the mask surface, more thorough leveling, and higher film thickness consistency, significantly improving spraying quality and process stability.

[0055] Combination Figures 1-6 As shown, in Example 1, the uniform coating method described in this application is used, and the uniform coating device described in this application is used to perform the coating process on a 6-inch photomask with a chromium layer, with a target film thickness of 200nm ± 5nm.

[0056] During the process, the cavity exhaust pressure is 200Pa±10Pa, the distance between the lower surface of the second ring plate 42 and the upper surface of the mask 3 is 10mm, the first speed is 10rpm, and the second speed is 1000rpm; the photoresist coating result is as follows. Figure 5 As shown in Figure A, the film thickness uniformity is 1%.

[0057] In Comparative Example 1, a conventional coating apparatus and method were used to perform the coating process on a 6-inch photomask with a chromium layer, with a target film thickness of 200 nm ± 5 nm; the test results obtained are as follows. Figure 5 As shown in Figure B, the film thickness uniformity is 42%.

[0058] In Example 2, the uniform coating method described in this application is used, and the uniform coating device described in this application is used to perform the coating process on a 6-inch photomask with a chromium layer, with a target film thickness of 450nm ± 5nm.

[0059] During the process, the cavity exhaust pressure is 300Pa±10Pa, the distance between the lower surface of the second ring plate 42 and the upper surface of the mask 3 is 10mm, the first speed is 20rpm, and the second speed is 1500rpm; the photoresist coating result is as follows. Figure 6 As shown in Figure A, the film thickness uniformity is 0.8%.

[0060] In Comparative Example 2, a conventional coating apparatus and method were used to perform the coating process on a 6-inch photomask with a chromium layer, with a target film thickness of 450 nm ± 5 nm; the test results obtained are as follows. Figure 6 As shown in Figure B, the film thickness uniformity is 38%.

[0061] It is evident that when conventional photoresist coating devices and methods are used to coat photomask 3, significant defects such as uneven film thickness, edge accumulation, and ripples are produced at the four corners of the square photomask. However, the results obtained by using the uniform photoresist coating device and method described in this application are significantly improved.

[0062] The above description of the embodiments is intended to enable those skilled in the art to understand and apply this application. It will be apparent to those skilled in the art that various modifications can be easily made to these embodiments, and the general principles described herein can be applied to other embodiments without creative effort. Therefore, this application is not limited to the embodiments described herein, and any improvements and modifications made by those skilled in the art based on the disclosure of this application without departing from the scope and spirit of this application are within the scope of this application.

Claims

1. An apparatus for uniformly applying adhesive, characterized in that, Includes an adhesive application chamber and the following components disposed within the adhesive application chamber: The support component includes a support platform for supporting the mask and a drive mechanism for driving the support platform to rotate and lift. The support platform is circular and has a rectangular recessed area in the middle. The support platform has four openings that divide the circumference of the support platform. Each opening corresponds to one of the four corners of the recessed area and communicates with the inside of the recessed area to form a drainage channel. A photoresist spraying component is disposed above the supporting component and is used to spray photoresist onto the surface of the photomask. A splash-proof component for accommodating the support component, wherein the top of the splash-proof component is provided with a first central through hole, and the support platform is located below the first central through hole; A lifting cover plate includes an annular cover plate and a lifting mechanism connected to the annular cover plate; the annular cover plate covers the first central through hole to compress the upper space of the edge of the mask plate; The exhaust component is connected to the bottom of the splash guard component.

2. The apparatus for uniformly applying adhesive according to claim 1, characterized in that, The splash-proof component includes a bottom cup, a middle cup, a flat cup, and an upper cup that are coaxially arranged from bottom to top. The exhaust component is connected to the bottom cup, and the bottom cup has a waste liquid collection tank. The middle cup, the flat cup, and the upper cup are all inverted cup-shaped structures, and a third central through hole, a second central through hole, and a first central through hole are respectively provided in the middle part of the bottom of the middle cup, the flat cup, and the upper cup. The supporting component is provided by the bottom cup passing through the third and second central through holes, so that the supporting platform is located above the middle cup and can move up and down between the flat cup and the upper cup.

3. The apparatus for uniformly applying adhesive according to claim 2, characterized in that, The flat cup includes a cylindrical flat cup outer wall and a first drainage part disposed inside the flat cup outer wall. The first drainage part has an upwardly protruding spherical structure, and a second central through hole is located at the center of the first drainage part. The connection between the first drainage part and the outer wall is provided with a plurality of vertically penetrating first waste liquid holes.

4. The apparatus for uniformly applying adhesive according to claim 2, characterized in that, The middle cup has a columnar middle cup side wall and a spherical frustum-shaped bottom surface protruding towards the flat cup. One end of the spherical frustum-shaped bottom surface is a large circle connected to the middle cup side wall, and the other end is a small circle. The center of the small circle end face is provided with the third central through hole. The end of the spherical frustum-shaped bottom surface near the large circle is provided with a plurality of second waste liquid holes that penetrate vertically.

5. The apparatus for uniformly applying adhesive according to claim 1, characterized in that, The annular cover plate includes a stepped first annular plate and a second annular plate. The second annular plate is disposed inside the first annular plate and is lower than the first annular plate. When the annular cover plate covers the first central through hole, the second annular plate extends into the interior of the splash-proof component to compress the upper space of the edge of the mask.

6. The apparatus for uniformly applying adhesive according to claim 5, characterized in that, The inner circle dimension of the annular cover plate is the same as the inscribed circle dimension of the mask.

7. The apparatus for uniformly applying adhesive according to claim 1, characterized in that, The bottom surface of the recessed area is provided with multiple support and anti-slip points to support the mask plate.

8. The apparatus for uniformly applying adhesive according to claim 7, characterized in that, The bottom surface of the recessed area is also provided with multiple cleaning holes, which are connected to an external cleaning liquid source through pipelines.

9. The apparatus for uniformly applying adhesive according to claim 1, characterized in that, The diameter of the support platform is the same as the diameter of the circumcircle of the mask.

10. A method for uniformly applying adhesive, applicable to the apparatus for uniformly applying adhesive as described in any one of claims 1-9, characterized in that, Includes the following steps: Raise the annular cover plate, control the support platform to rise to the loading position, and place the mask in the recessed area of ​​the support platform; The support platform is controlled to descend to the process position, the annular cover plate descends to cover the first central through hole on the top of the splash-proof component, and the exhaust component is activated to exhaust air from the inside of the splash-proof component; The adhesive spraying component is controlled to spray photoresist onto the surface of the photomask, while the support stage is controlled to rotate sequentially at a first speed and a second speed to spread the photoresist; wherein the second speed is greater than the first speed. The support stage is controlled to rotate at a step-down speed in response to the end of the photoresist spraying until the support stage stops rotating.

11. The method for uniformly applying adhesive according to claim 10, characterized in that, When the device for uniformly applying adhesive includes support anti-slip points and cleaning holes, the control platform rotates at a step-down speed while simultaneously spraying cleaning fluid from the cleaning holes onto the bottom surface of the mask.

12. The method for uniformly applying adhesive according to claim 10, characterized in that, The method for uniformly applying photoresist further includes: spraying a photoresist thinner onto the top surface of the photomask before the photoresist spraying component sprays photoresist onto the surface of the photomask.

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