Photoresist coating equipment and photoresist coating method

Abstract

The invention discloses photoresist coating equipment and a photoresist coating method, and relates to the technical field of transformers. The coating device specifically comprises a rotary table, a coating chamber and an air source used for providing airflow, the top of the coating chamber is closed, the rotary table is rotatably arranged in the coating chamber, the top of the rotary table is used for fixing a workpiece, an annular space is formed between the rotary table and the inner side wall of the coating chamber, the air source is arranged at the top of the coating chamber, and the air source is arranged in the annular space. The air source is used for generating air flow towards the rotary table, an exhaust port is formed in the bottom of the coating chamber, guide vanes are arranged in the coating chamber and used for enabling the air flow generated by the air source to form rotating air flow, and the rotating direction of the rotating air flow is the same as that of the rotary table. The rotating airflow acts on the workpiece and is used for preventing the photoresist from being accumulated at the corner of the workpiece, so that the effect of preventing the photoresist from being accumulated at the corner of the workpiece is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of transformers, and specifically provides a photoresist coating device and a photoresist coating method. Background Art

[0002] The existing method for coating photoresist mainly uses the spin coating method. The photoresist is sprayed at the center of the workpiece, and then the workpiece is rotated. Under the action of centrifugal force, the photoresist flows towards the edge of the workpiece and finally covers the workpiece, forming a thin layer on the surface of the workpiece.

[0003] When the workpiece rotates, the photoresist flows towards the edge of the workpiece. Affected by factors such as its own inertia, the flow path of the photoresist is spiral. That is to say, the flow velocity of the photoresist can be decomposed into a radially outward direction and a tangential direction. When the shape of the workpiece is circular, the photoresist can flow along the tangent direction of the circular workpiece at any position during rotation, making it easy for the photoresist to be evenly distributed. However, when the shape of the workpiece is square, when the photoresist flows along the top surface of the workpiece to the corner position of the workpiece, the photoresist cannot continue to flow along the tangent direction. And during continuous rotation, the photoresist at the corner position will accumulate on the side opposite to the rotation direction at the corner, resulting in uneven distribution of the photoresist on the surface of the workpiece. Summary of the Invention

[0004] The present invention provides a photoresist coating device and a photoresist coating method, which are used to solve the problem that the photoresist at the corner of the workpiece accumulates on one side, resulting in uneven distribution of the photoresist on the surface of the workpiece.

[0005] The technical solution of the present invention is as follows:

[0006] A photoresist coating device includes a turntable, a coating chamber, and a gas source for providing air flow. The top of the coating chamber is closed. The turntable is rotatably arranged in the coating chamber. The top of the turntable is used to fix the workpiece. An annular space is formed between the turntable and the inner side wall of the coating chamber. The gas source is arranged at the top of the coating chamber. The gas source is used to generate an air flow towards the turntable. An exhaust port is arranged at the bottom of the coating chamber. A guide vane is arranged in the coating chamber. The guide vane is used to make the air flow generated by the gas source form a rotating air flow, and the rotation direction of the rotating air flow is the same as the rotation direction of the turntable.

[0007] In this solution, the airflow generated by the air source forms a rotating airflow under the action of the guide vanes. The rotation direction of the rotating airflow is the same as that of the turntable. The photoresist moves along the radial direction of the turntable under the action of the rotating airflow. The tangential force acting on the photoresist caused by the rotation of the turntable is offset by the rotating airflow, thereby avoiding the accumulation of photoresist at the corners of the workpiece and enabling the photoresist at the corners of the workpiece to be evenly distributed. In this application, the top of the coating chamber is closed to prevent the airflow in the external environment from interfering with the rotating airflow. At the same time, it can prevent external impurities from entering the coating chamber and causing pollution. With the top of the coating chamber closed, the airflow ejected by the air source can be discharged from the bottom of the coating chamber.

[0008] To solve the problem that it is inconvenient to pick up and place the workpiece, for this purpose, the coating chamber includes a side enclosure and an upper cover. The upper cover is detachably connected to the side enclosure. The upper cover is used to close the upper part of the side enclosure, and the air source is arranged on the upper cover.

[0009] In this solution, the upper cover is detachably connected to the side enclosure. By opening the upper cover, the workpiece can be picked up and placed, which is convenient for picking up and placing the workpiece. After the workpiece is placed, the cover can be closed to seal the top of the coating chamber again.

[0010] To solve the problem that the guiding effect of the guide vanes is limited and the guide vanes cannot be adjusted during operation, and thus the rotation speed of the rotating airflow cannot be affected, for this purpose, the side enclosure includes a fixed inner layer and a movable outer layer. The inner layer is rotatably connected to the outer layer. The top of the outer layer is connected to the upper cover, and the inner layer is provided with guide vanes.

[0011] In this solution, the inner layer is rotatably connected to the outer layer. When the inner layer rotates at different speeds, the guide vanes rotate with the inner layer, thereby affecting the rotation speed of the rotating airflow and enabling the rotating airflow in the coating chamber to be adjusted during operation. Moreover, the inner layer driving the guide vanes can enhance the guiding effect of the guide vanes and make the rotating airflow form more stably.

[0012] To prevent the workpiece from moving, a positioning groove is provided at the top of the turntable, and the positioning groove is used to position the workpiece.

[0013] When the workpiece is a rectangular workpiece, the photoresist flows along the surface of the workpiece and contacts the workpiece surface during the flow process, thereby forming a thin film on the workpiece surface. Therefore, as the photoresist flows, the flowable photoresist on the workpiece surface continuously decreases. As the flowable photoresist decreases, the remaining flowable photoresist is increasingly affected by the adhesive force between the photoresists. When the photoresist is subjected to the centrifugal force of the turntable rotation, its fluidity becomes worse, resulting in insufficient photoresist flowing to the corner positions of the workpiece, causing uneven distribution of the photoresist on the workpiece. For this reason, the shape of the positioning groove is rectangular, and a plurality of air extraction holes are provided on the turntable. The plurality of air extraction holes are used to form a negative pressure outside each corner of the positioning groove, and the negative pressure promotes the photoresist on the workpiece surface to flow towards each corner of the workpiece.

[0014] In this solution, the air extraction holes can form a negative pressure at the corners of the workpiece. The closer to the air extraction holes, the stronger the negative pressure effect. That is to say, when the photoresist gradually flows to the corners of the workpiece, although the adhesive force of the photoresist itself increases when it flows to the corners of the workpiece, the negative pressure effect of the air extraction holes it receives gradually increases, and the negative pressure cancels out the adhesive force with each other, so that the remaining flowable photoresist can flow to the corners of the workpiece, making the distribution of the photoresist on the workpiece uniform. The advantage of this setting method is that it does not require changing the rotation speed of the turntable and will not affect the distribution of the photoresist in the middle of the workpiece.

[0015] The air flow acts on the workpiece surface from top to bottom, which is equivalent to the air flow directly impacting on the workpiece surface. The air flow contacts the workpiece surface and detaches from the workpiece in a sputtering manner. In severe cases, it even carries some sputtered photoresist, making the thin film formed by the photoresist uneven. For this reason, the exhaust port is connected to a negative pressure device to form a negative pressure at the bottom of the turntable.

[0016] In this solution, a negative pressure is formed around the drill table, and the air flow flows towards the negative pressure area after contacting the workpiece. Since the negative pressure area is located at the bottom of the turntable, the air flow can flow flatly along the workpiece surface to the edge of the turntable and then flow downward from the annular space around the turntable. Because the air flow will flow flatly along the workpiece, sputtering can be avoided.

[0017] Preferably, the guide vane is movably connected to the inner side wall of the coating chamber for adjusting the angle between the guide vane and the inner side wall of the coating chamber.

[0018] In this solution, the rotation speed of the rotating air flow can be changed by adjusting the angle of the guide vane, so that the rotation speed of the rotating air flow is adjustable to suit different production situations.

[0019] The present invention also provides a photoresist coating method, which is suitable for the above-mentioned photoresist coating equipment. The workpiece is fixed on a turntable, and the photoresist is coated on the workpiece by spin coating. At the same time, a rotating airflow with the same rotation direction as the turntable is applied to the workpiece, so that the photoresist at the corners of the workpiece can be evenly distributed through the rotating airflow.

[0020] In this solution, a rotating airflow is used to prevent the photoresist from accumulating at the corners of the workpiece, so as to solve the problem of uneven photoresist coating.

[0021] Preferably, a negative pressure environment is created on the lower side of the turntable, and the negative pressure constrains the path of the airflow, so that the rotating airflow flows along the surface of the workpiece to prevent the photoresist from sputtering.

[0022] In this solution, the airflow will automatically flow in the direction of negative pressure, which is the direction toward the lower side of the turntable. After the airflow contacts the workpiece, it will flow along the surface of the workpiece toward the circumference of the turntable, and then flow from the periphery of the turntable to the bottom of the turntable. This setting method prevents the airflow from rebounding upward after contacting the workpiece, but flows along the surface of the workpiece to avoid photoresist sputtering when the airflow rebounds. The airflow flowing along the surface of the workpiece will also drive the photoresist to flow toward the edge of the workpiece, so that the photoresist can be more evenly coated on the workpiece.

[0023] In order to solve the problem that the photoresist has poor fluidity at the corners of a square workpiece and is difficult to flow to the corners of the workpiece, a negative pressure environment is set at each corner of the workpiece so that the air pressure at the corner of the workpiece edge is lower than the air pressure at other edges. The negative pressure environment is used to guide the photoresist in the middle of the workpiece to flow to the corners of the workpiece.

[0024] In this solution, because the air pressure at the corners of the workpiece is lower, the airflow corresponding to the corners flows faster, exerting a greater force on the photoresist, so that the photoresist can flow smoothly to the corners, ensuring that the photoresist is more evenly distributed throughout the workpiece.

[0025] Beneficial effects of the present invention:

[0026] The present invention adopts a rotating airflow to act on the workpiece, and the rotating airflow is used to prevent the photoresist from accumulating at the corners of the workpiece, thereby preventing the photoresist from accumulating at the corners of the workpiece. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solution of the present invention, the drawings required for describing the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1Cross-sectional view of an embodiment of the present invention;

[0029] Figure 2 Top view of an embodiment of the inner layer and the guide vane of the present invention;

[0030] Figure 3 Cross-sectional view of a connection mode between the inner layer and the outer layer of the present invention;

[0031] Figure 4 Top view of the turntable of the present invention.

[0032] In the above-mentioned drawings, the corresponding reference numerals are shown as follows:

[0033] 1. Fan filter unit; 2. Upper cover; 3. Coating cavity; 4. Side enclosure; 5. Exhaust port; 6. Bottom plate; 7. Turntable; 8. Guide vane; 9. Air extraction hole; 10. Positioning groove; 11. Air extraction pipeline; 41. Outer layer; 42. Inner layer; 43. Slide block. Specific embodiments

[0034] In combination with the drawings, through the specific embodiments of the embodiments of the present invention, the technical solutions of the present invention are clearly and completely described.

[0035] Embodiment 1:

[0036] As Figure 1 shown, Embodiment 1 of the present invention provides a photoresist coating device, including a turntable, a side enclosure, an upper cover, a fan filter unit and a guide vane. Among them, the side enclosure is a ring structure, the turntable is rotatably arranged inside the side enclosure, the upper cover is detachably connected to the side enclosure. When the upper cover is connected to the side enclosure, the space at the top of the turntable is closed, so that the external air flow cannot interfere with the turntable. After the upper cover is connected to the side enclosure, the cavity formed inside is a coating chamber. The fan filter unit is arranged on the inner side surface of the upper cover. The fan filter unit is used to output a downward air flow, so that the air flow acts on the workpiece and assists the photoresist to flow and be evenly coated on the surface of the workpiece. The guide vane is arranged on the inner side surface of the side enclosure. The guide vane is inclined relative to the horizontal plane. The air flow output by the fan filter unit is vertically downward. During the flow of the air flow, it will pass through the guide vane. Under the guiding action of the guide vane, a rotating air flow is formed. The overall direction of the rotating air flow still flows downward, but at the same time it will rotate horizontally. The rotating direction of the rotating air flow is the same as the rotating direction of the turntable, and the rotating speed of the rotating air flow is greater than the rotating speed of the turntable, so as to ensure that the rotating air flow can give the photoresist a force along the rotating direction of the turntable, avoiding the accumulation of the photoresist on one side of the corner. Therefore, under the action of the rotating air flow, the photoresist at the corner of the workpiece can be evenly distributed.

[0037] The shape of the side enclosure is cylindrical. The side enclosure includes an outer layer fixedly installed and an inner layer movably installed. This device also includes a frame. The outer layer is fixedly installed on the frame, and the turntable is rotatably connected to the frame. The inner layer can be movably connected, which means that the inner layer can rotate around the axis. The inner layer can be rotatably connected to the frame. For example, bearings are provided on the frame, the outer ring of the bearing is connected to the inner layer, and the inner ring of the bearing is fixedly connected to the frame. The inner layer can also be rotatably connected to the outer layer. As Figure 3 shown, a slider is provided at the bottom of the inner layer, and an annular chute for guiding is provided on the outer layer. The slider is slidably connected to the chute. When installing the slider, the inner layer can be first inserted into the outer layer, then the slider can be moved to the position of the chute, and finally the slider can be fixed to the inner layer. The slider is located at the end of the inner layer, or through holes penetrating the inside and outside are opened on the inner layer to facilitate the installation of the slider.

[0038] As Figure 2 shown, the guide vanes are arranged on the inner side surface of the inner layer along the circumferential direction of the inner layer. The inclination angle of the guide vanes relative to the horizontal plane is 30° - 60°. The smaller the inclination angle of the guide vanes, the faster the rotational speed of the rotating air flow.

[0039] The inclination angle of the guide vanes can be adjusted so that the rotational speed of the rotating air flow can also be adjusted. For example, fixing holes are opened on the inner side surface of the inner layer, and a fixing rod is provided at one end of the guide vane. After the fixing rod is inserted into the fixing hole, the connection between the guide vane and the inner layer is realized. The fixing rod and the fixing hole can be fixed by glue. Before the fixing rod is fixedly connected to the fixing hole, the inclination angle of the guide vane is first adjusted. After the fixing rod is fixedly connected to the fixing hole, the inclination angle of the guide vane is also fixed. The above example is a fixing method of the guide vane. The fixing rod can also be prismatic, and the fixing hole is a prismatic hole adapted to it. This installation method enables the guide vane to have several fixed inclination angles. The disadvantage is that the angle adjustment range is small, only several fixed angles, and the advantage is that the angle adjustment operation is simpler and faster.

[0040] Moreover, because the inner layer is rotatably connected to the outer layer, rotating the inner layer to make the guide vanes rotate can also affect the rotational speed of the rotating air flow. Therefore, this solution has two adjustment methods for the rotational speed of the rotating air flow. One is to change the inclination angle of the guide vanes, and the other is to change the rotational speed of the inner layer. Changing the guide vanes needs to be adjusted before work. For example, when different photoresists need to be coated, the inclination angle of the guide vanes is changed according to the physical properties such as the viscosity of different photoresists. For example, the greater the viscosity of the photoresist, the greater the rotational speed of the rotating air flow in the horizontal direction is required, and then the inclination angle of the guide vanes needs to be set smaller to increase the flow rate of the rotating air flow in the horizontal direction and enhance the effect of the rotating air flow on the photoresist.

[0041] The rotation of the inner layer and the rotation of the turntable both adopt power motors. Different power motors are used to drive the inner layer and the turntable, so that the power of the inner layer is independent of the power of the turntable. A gear ring can be arranged on the inner layer. The power motor is fixed on the frame, and a gear is arranged on the output shaft of the power motor. The gear meshes with the gear ring to transmit the power of the power motor to the inner layer. The power motor used to drive the turntable is also fixed on the frame, and the output shaft of the power motor can be connected to the turntable through a gear or a coupling to drive the turntable to rotate.

[0042] The inner layer is driven by a power motor. During the rotation of the turntable, by controlling the power of the power motor, the rotation speed of the inner layer can be controlled, thereby controlling the rotation speed of the rotating air flow, so that the rotating air flow maintains different rotation speeds at different stages of photoresist coating.

[0043] The coating of the photoresist includes the following three stages. The first stage is when the photoresist drops on the surface of the workpiece. At this time, the turntable rotates slowly or remains stationary, and the inner layer rotates at a low speed or does not rotate. The second stage is the stage where the glue liquid diffuses slowly around. At this time, the turntable rotates slowly to prevent the glue liquid from quickly diffusing around and resulting in too thin a thickness of the glue liquid in the middle. At this time, the inner layer also rotates slowly, and the rotation speed of the formed rotating air flow is low. The third stage is the stage of high-speed spin coating to form a stable film. At this time, the rotation speed of the turntable is further increased to quickly spread the glue liquid that has already spread on the surface of the workpiece to form a film. In this stage, the glue liquid of the photoresist will quickly spread and cover the entire surface of the workpiece. During this process, the rotation speed of the inner layer also increases to the fastest to ensure that when the photoresist flows to the corner of the workpiece, it can flow along the radial direction of the turntable, avoiding the stacking of the photoresist on one side of the corner of the workpiece due to factors such as its own viscosity.

[0044] A positioning groove is arranged on the top of the turntable, and the positioning groove is used to position the workpiece. The technical solution of the present invention is mainly used to solve the problem that photoresist is likely to accumulate at the corners of square workpieces. Therefore, the shape of the positioning groove is adapted to the shape of the workpiece. When the shape of the workpiece is square, the shape of the positioning groove is square. Since the current shapes of workpieces are mainly circular and square, the positioning groove of this application is mainly used to place square workpieces, and the shape of the positioning groove is square. Similarly, if the shape of the workpiece is an equilateral triangle or a regular hexagon, then the shape of the positioning groove is also set to a polygon shape such as an equilateral triangle or a regular hexagon.

[0045] A bottom plate is also arranged on the frame at the lower side of the side enclosure. The bottom plate is connected to the side enclosure. The bottom plate is used to close the bottom of the side enclosure, and an exhaust port is opened on the bottom plate. The fan filter unit is used as the air source to input air flow into the coating chamber, and the input gas is discharged from the exhaust port. The function of setting the bottom plate is to close the bottom of the side enclosure, so that a negative pressure environment can be formed inside the side enclosure.

[0046] The air flow speed input by the fan filter unit is fast. When it contacts the workpiece surface, it is easy to rebound or sputter upward or obliquely upward, resulting in partial sputtering of the photoresist and uneven distribution of the photoresist on the workpiece surface. To prevent the air flow from causing photoresist sputtering, a negative pressure device, such as a suction pump, is connected to the exhaust port. The suction pump extracts the gas in the coating chamber, creating a negative pressure environment at the exhaust port, causing the gas in the coating chamber to flow towards the exhaust port. There is a gap between the turntable and the side enclosure, forming an annular space. Therefore, the air flow on the upper side will flow from the annular space to the lower side of the turntable and finally be discharged from the exhaust port. Under the guiding action of this negative pressure environment, the air flow will flow along the workpiece surface and the turntable surface after contacting the workpiece, and then flow into the annular space. By creating a negative pressure environment to affect the flow direction of the air flow, making the air flow flow along the workpiece and turntable surfaces, it can prevent situations such as air flow rebound and sputtering, and can also make the air flow drive the photoresist towards the edge of the workpiece, making the distribution of the photoresist more uniform. In addition, the rotating air flow of the present application itself has a certain horizontal speed, so it can more smoothly transform into a horizontal flow state when contacting the workpiece surface, preventing the situation of photoresist sputtering.

[0047] The air pressure at the annular space around the turntable is 300 - 400 Pa lower than the standard atmospheric pressure.

[0048] The rotation speed of the turntable will affect the centrifugal force received by the photoresist. When the rotation speed of the turntable is too fast, the greater the centrifugal force received by the photoresist, the greater the movement range of the photoresist. Therefore, reasonably controlling the rotation speed of the turntable is related to the magnitude of the centrifugal force received by the photoresist and the movement range of the photoresist. When the workpiece is circular, the distance between any point on the workpiece edge and the workpiece center is the same. Therefore, there will be no problem of uneven distribution of the photoresist at the workpiece edge. When the shape of the workpiece is square, the distance from the workpiece edge to the workpiece center is different. At this time, the content of the photoresist at the workpiece edge must be different. Especially at the corners of the workpiece, the distance from the corners to the center of the workpiece is the farthest, so the distribution of the photoresist is the least. To make the distribution of the photoresist more uniform, in this embodiment, air extraction holes are provided on the turntable. The positions of the air extraction holes are outside the positioning grooves, and the air extraction holes are directed towards the corners of the positioning grooves. The function of the air extraction holes is to create a negative pressure environment at the corners of the workpiece, making the air flow speed faster at the corners, so that the air flow can drive the photoresist towards the corners of the workpiece, making the distribution of the photoresist on the workpiece surface more uniform.

[0049] As Figure 4 shown, a number of air extraction holes are provided on the turntable, and air extraction holes are provided on the outside of each corner of the positioning groove. By creating different negative pressure environments around the workpiece, the air flow velocity is controlled, and the air flow enables the photoresist to flow towards the corners, making the distribution of the photoresist on the workpiece surface more uniform.

[0050] The air extraction hole can be the air inlet hole of the air extraction pipeline. The air extraction pipeline protrudes from the top of the turntable, making the air extraction hole face the corner of the workpiece. The bottom end of the air extraction pipeline is connected to another air extraction pump.

[0051] It should be noted that the fan filtration unit in the first embodiment is a combined device including a fan and a filtration device. The fan filtration unit is used to extract air from the external environment, filter the air, and output a stable air flow. In other embodiments, if it can be ensured that there are no impurities in the gas that affect the photoresist coating, only a fan or an air delivery pipeline can be provided.

[0052] It should be noted that in the prior art, a nozzle for spraying photoresist is provided inside the side enclosure. After the workpiece is placed on the turntable, the nozzle is controlled to spray the photoresist at the center of the workpiece. Then the turntable rotates to evenly coat the photoresist on the surface of the workpiece under the action of centrifugal force.

[0053] The photoresist itself includes a solvent and other components dissolved in the solvent, such as photosensitizers and resins. A mass spectrometer for monitoring the concentration of the photoresist solvent is provided inside the side enclosure. During the coating process of the photoresist, the solvent of the photoresist will continuously volatilize. The mass spectrometer monitors the concentration of the volatilized substances in the air. According to the concentration of the volatilized substances in the air, the state of the photoresist can be judged to determine whether the photoresist is cured on the surface of the workpiece to form a stable film. After the mass spectrometer detects that the concentration of the volatilized substances in the air is lower than a set threshold, the speed of the turntable can be reduced, and the rotation speed of the turntable can be gradually stopped to complete the work of coating the photoresist on the workpiece. Therefore, a controller can be provided. The power motor for driving the turntable, the power motor for driving the inner ring to rotate, the fan filtration unit, the air extraction pump for forming negative pressure, and the mass spectrometer are respectively electrically connected to the controller. The controller controls each power motor, the fan filtration unit, and the air extraction pump according to the signal of the mass spectrometer. When the volatilized substances in the air are lower than a set threshold, the controller controls each power motor, the fan filtration unit, and each air extraction pump to gradually reduce the power and finally stop working.

[0054] The controller can be a PLC, a single-chip microcomputer, etc.

[0055] Embodiment 2:

[0056] The second embodiment provides a photoresist coating method, which can be applied to the photoresist coating equipment described in the first embodiment.

[0057] This method uses the traditional spin coating method to coat photoresist on the surface of the workpiece. That is, the workpiece is fixed on a turntable, and photoresist is dropped in the middle of the workpiece. Due to the centrifugal force generated by the rotation of the turntable, the photoresist flows towards the edge of the workpiece, and finally a thin film formed by photoresist with a uniform thickness is coated on the surface of the workpiece. The difference between this method and the traditional spin coating method is that while the turntable is rotating, a rotating air flow acts on the surface of the workpiece, and the rotating direction of the rotating air flow is the same as the rotating direction of the turntable. By applying a circumferential force to the photoresist at the corner of the workpiece through the rotating air flow, the photoresist will accumulate on one side of the corner due to the centrifugal force, causing the photoresist accumulated at the corner to flow towards other positions at the corner, making the distribution of the photoresist at the corner more uniform.

[0058] Another difference of this method is that this method places the turntable in a closed space to prevent the outside air from affecting the air flow at the turntable. Then, a negative pressure environment is created under the turntable, causing the air flow to flow along the surface of the workpiece and the turntable to the edge of the turntable, and then flow downward from the edge of the turntable. This way, the air flow on the upper side of the turntable as a whole flows from the middle of the turntable to the edge of the turntable. Due to the reason that the overall direction of the air flow is from the middle of the turntable to the edge of the turntable, and the air flow itself is a rotating air flow, therefore, the entire air flow is equivalent to several stratospheres, and the air flows in different layers will restrict each other, causing the air flow in the lowermost layer to flow flat against the surface of the workpiece or the turntable, avoiding the air flow from splashing the photoresist.

[0059] Another difference of this method is that a negative pressure environment is created at the corner of the workpiece, making the negative pressure environment around the workpiece different. The air pressure at the corner is lower, and the air flow velocity at the corner is greater, so that the air flow can flow the photoresist to the corner. The negative pressure environment at the corner is used to guide the photoresist to flow towards the corner.

Claims

1. A photoresist coating device, characterized in that, It includes a turntable, a coating chamber and a gas source for providing an air flow. The top of the coating chamber is closed. The turntable is rotatably arranged in the coating chamber. The top of the turntable is used to fix a workpiece. An annular space is formed between the turntable and the inner side wall of the coating chamber. The gas source is arranged at the top of the coating chamber and is used to generate an air flow towards the turntable. An exhaust port is arranged at the bottom of the coating chamber. Guide vanes are arranged in the coating chamber and are used to make the air flow generated by the gas source form a rotating air flow, and the rotating direction of the rotating air flow is the same as the rotating direction of the turntable.

2. The lithography resist coating apparatus according to claim 1, wherein The coating chamber includes a side enclosure and an upper cover. The upper cover is detachably connected to the side enclosure and is used to close the upper part of the side enclosure. The gas source is arranged on the upper cover.

3. A photoresist coating apparatus according to claim 2, wherein, The side enclosure includes a fixedly installed inner layer and a movably installed outer layer. The inner layer and the outer layer are rotatably connected. The top of the outer layer is connected to the upper cover. The inner layer is provided with guide vanes.

4. A photoresist coating apparatus according to claim 1, wherein A positioning groove is arranged at the top of the turntable and is used to position the workpiece.

5. A photoresist coating apparatus according to claim 4, wherein The shape of the positioning groove is rectangular. A plurality of air extraction holes are arranged on the turntable. The plurality of air extraction holes are used to form a negative pressure outside each corner of the positioning groove, and the negative pressure is used to promote the photoresist on the surface of the workpiece to flow towards each corner of the workpiece.

6. A photoresist coating apparatus according to claim 1, characterized in that The exhaust port is connected to a negative pressure device and is used to form a negative pressure at the bottom of the turntable.

7. A photoresist coating apparatus according to claim 1, characterized in that, The guide vanes are movably connected to the inner side wall of the coating chamber and are used to adjust the angle between the guide vanes and the inner side wall of the coating chamber.

8. A photoresist coating method, characterized in that, Applicable to the photoresist coating equipment according to any one of claims 1-7, fix the workpiece on the turntable, use the spin coating method to coat the photoresist on the workpiece, and at the same time use a rotating air flow with the same rotating direction as the turntable to act on the workpiece, so that the photoresist at the corners of the workpiece can be evenly distributed.

9. A method for coating a photoresist according to claim 8, characterized in that, Create a negative pressure environment on the lower side of the turntable, and constrain the path of the air flow through the negative pressure, so that the rotating air flow flows along the surface of the workpiece to prevent the photoresist from splashing.

10. A photoresist coating method according to claim 8, characterized in that, Set a negative pressure environment at each corner of the workpiece, so that the air pressure at the corners of the edge of the workpiece is lower than that at other edges, and guide the photoresist in the middle of the workpiece to flow to the corners of the workpiece through the negative pressure environment.

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