Substrate processing apparatus and substrate processing method

Abstract

The present invention provides a substrate processing apparatus and a substrate processing method that can improve the cleanliness of a substrate. The substrate processing apparatus (1) of the embodiment includes: a rotating body (10) including a mounting part (13) that mounts a substrate (W) having a surface to be processed, and the substrate (W) is mounted in such a way that a space is maintained between the surfaces of the substrate (W) opposite to the surface to be processed; a rotation drive part (16) that rotates the rotating body (10); a liquid supply part (30, 40) that supplies liquid to the surface to be processed of the substrate (W); a cooling part (20) that supplies cooling gas to the space between the substrate (W) and the mounting part (13); and a removal part (90) that removes droplets (D) from the surface of the rotating body (10) facing the substrate (W).

Description

Technical Field

[0001] The embodiments of the present invention relate to a substrate processing apparatus and a substrate processing method. Prior Technology

[0002] Freeze cleaning is one of the known methods for removing and cleaning foreign matter such as particles that adhere to the surface of substrates such as embossing stencils, photolithography masks, and semiconductor wafers.

[0003] In the freeze cleaning method, various liquids can be used as the cleaning liquid. When using pure water, firstly, pure water and cooling gas are supplied to the surface of the rotating substrate to be treated. Next, the supply of pure water is stopped, and a portion of the supplied pure water is discharged from the substrate, forming a water film (liquid film) on the surface of the substrate to be treated. The water film is frozen by the cooling gas supplied to the substrate. As the water film freezes to form an ice film, foreign matter such as particles is trapped in the ice film and thus separated from the surface of the substrate to be treated. Next, pure water is supplied to the ice film to melt it, removing the foreign matter along with the pure water from the surface of the substrate to be treated.

[0004] However, when cooling gas is supplied from the side of the substrate where the water film is formed, freezing begins from the surface side of the water film (the side of the water film opposite to the substrate side). When freezing begins from the surface side of the water film, it is difficult to separate foreign matter adhering to the treated surface of the substrate. Therefore, a technique has been proposed to supply cooling gas from the side of the substrate opposite to the treated surface (the side of the substrate opposite to the side where the water film is formed). [Existing Technical Documents] [Patent Literature]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2018-026436 Summary of the Invention

[0006] [The problem that the invention aims to solve] However, when cooling gas is supplied to the substrate, not only the substrate but also the rotating body of the mounting section that holds the substrate is cooled. As the rotating body cools and its temperature drops, the surrounding environment becomes colder due to the cooled rotating body, causing condensation to form on the surface of the rotating body facing the substrate. Due to the condensation, droplets containing particles from the environment remain on the surface of the rotating body facing the substrate. These residual droplets may contaminate the substrate, especially the surface opposite to the surface being processed.

[0007] The embodiments of the present invention are proposed to solve the problems described above, and their purpose is to provide a substrate processing apparatus and substrate processing method that can improve the cleanliness of the substrate. [Methods for solving problems]

[0008] The substrate processing apparatus according to an embodiment of the present invention includes: a rotating body including a mounting section that mounts a substrate having a surface to be processed, and the mounting section mounts the substrate in such a way that a space is maintained between a surface of the substrate opposite to the surface to be processed; a rotation drive section that rotates the rotating body; a liquid supply section that supplies liquid to the surface to be processed of the substrate; a cooling section that supplies cooling gas to the space between the substrate and the mounting section; and a removal section that removes droplets from the rotating body on the surface facing the substrate.

[0009] The substrate processing method of the present invention involves placing a substrate on a mounting portion, rotating a rotating body including the mounting portion while the substrate is mounted, supplying liquid to the surface of the substrate opposite to the mounting portion side (i.e., the surface to be processed), supplying cooling gas to the space between the substrate and the mounting portion, freezing the liquid supplied to the surface to be processed, and removing droplets from the rotating body on the surface facing the substrate. [The effects of the invention]

[0010] The cleanliness of the substrate can be improved through the embodiments of the present invention. Simple Explanation of the Diagram

[0011] Figure 1 is an overall structural diagram showing the structure of the substrate before it is moved into the substrate processing apparatus of the first embodiment. Figure 2 is an overall structural diagram showing the structure when the substrate is moved in in the substrate processing apparatus of the first embodiment. Figure 3 is a structural diagram showing the structure of the rotating body, detection unit, and removal unit of the substrate processing apparatus according to the first embodiment. Figure 4 is a flowchart illustrating the operation of the substrate processing apparatus according to the first embodiment. Figure 5 is a schematic diagram showing the structure of the rotating body, detection unit, and removal unit after the substrate is removed in the first embodiment. Figure 6 is a schematic diagram showing the position of the sensor section of the detection unit during droplet detection in the first embodiment. Figure 7 is a schematic diagram showing the position of the nozzle of the removal section during droplet removal in the first embodiment. Figure 8 is a schematic diagram showing the structure of the removal section in a modified example of the first embodiment. Figure 9 is a schematic diagram showing the structure of the removal part in a modified example of the first embodiment. Figure 10 is an overall structural diagram showing the structure when the substrate is moved into the substrate processing apparatus in a modified example of the first embodiment. Figure 11 is a plan view showing the structure of the dispersion plate in a modified example of the first embodiment. Figure 12 is an explanatory diagram showing the residual position of the droplet in a modified example of the first embodiment. Figure 13 is a schematic diagram showing the position of the nozzle of the removal section during droplet removal in a modified example of the first embodiment. Implementation

[0012] [1. First Implementation Method] [1-1. Overview of the Apparatus]

[0013] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, in each drawing, the same reference numerals are used for the same constituent elements and detailed descriptions are omitted where appropriate. The substrate W to be processed can be, for example, a semiconductor wafer, an imprinting template, a photolithography mask substrate, or a plate-like body used in microelectromechanical systems (MEMS). However, the application of the substrate W is not limited to these. When the substrate W is a photolithography mask, the planar shape of the substrate W can be approximately quadrilateral. In this embodiment, the planar shape of the substrate W is circular. Furthermore, the surface of the substrate W with formed irregularities is designated as the surface to be processed. The irregularities can be, for example, patterns.

[0014] As shown in Figures 1 and 2, the substrate processing apparatus 1 of this embodiment cleans the surface of the substrate W to be processed by means of a freeze cleaning method.

[0015] In the freeze-cleaning method, cooling gas is used to freeze the liquid supplied to the surface of the substrate W to be processed. At this time, while rotating the substrate W, liquid is supplied to the surface of the substrate W to be processed, and cooling gas is supplied from the side of the substrate W opposite to the surface to be processed to cool the substrate W, thereby cooling and freezing the liquid on the surface to be processed. Therefore, in the substrate processing apparatus 1, a rotating body including a mounting section is provided. The mounting section holds the substrate W in such a way that a space is maintained between the surface of the substrate W opposite to the surface to be processed. While rotating the rotating body by a rotation drive, cooling gas is supplied between the mounting section and the substrate W.

[0016] Thus, by using cooling gas, not only the substrate W, but also the rotating body of the mounting portion on which the substrate W is placed, especially the surface of the rotating body facing the side opposite to the surface of the substrate W to be processed, is cooled. Therefore, for example, when the substrate W, whose surface to be processed has been cleaned, is moved outside the frame, ambient temperature external gas flows from outside the frame into the vicinity of the rotating body, and the flowing external gas is cooled by the cooled rotating body. As the flowing external gas is cooled by the rotating body, droplets caused by condensation are generated on the surface of the rotating body facing the substrate W. The substrate processing apparatus 1 of this embodiment determines whether there are droplet residues on the surface of the rotating body facing the substrate W, and if it is determined that there are droplet residues, it performs droplet removal processing.

[0017] [1-2. Structure of the First Embodiment] To perform the processing described above, the substrate processing apparatus 1 of this embodiment includes: a rotating body 10 having a mounting portion 13 for mounting a substrate W; a cooling portion 20 supplying cooling gas G between the substrate W and the mounting portion 13; a first liquid supply portion 30 supplying a first liquid (processing liquid L1) to the surface to be processed; a second liquid supply portion 40 supplying a second liquid (processing liquid L2) for removing the frozen first liquid from the surface to be processed; a frame 60 housing the rotating body 10, etc., forming a space for processing the substrate W; a detection portion 80 detecting droplets D on the surface of the rotating body 10 facing the substrate W; a removal portion 90 removing droplets D generated on the surface of the rotating body 10 facing the substrate W; and a control portion 100 controlling each portion. The structure of each portion will be described in detail below.

[0018] (Solid of Revolution) The rotating body 10 includes a disc-shaped rotating body base 11, and a hollow rotating shaft 12 at its center, the rotating shaft 12 extending in the opposite direction to the mounting portion 13 on which the substrate W is mounted. The rotating body base 11 has a central opening, and the disc-shaped mounting portion 13 with the central opening is embedded in its upper part. A nozzle 14 is provided in the central opening of the mounting portion 13, inserted into the hollow rotating shaft 12. The nozzle 14 is fixed to a frame (not shown) with a certain gap between it and the mounting portion 13 and the rotating shaft 12, and will not rotate even if the rotating body 10 rotates. A through hole is formed in the center of the nozzle 14 to serve as a cooling nozzle 24 for the cooling portion 20 described later. Here, the surface of the rotating body 10 facing the substrate W (hereinafter referred to as the facing surface) includes the surface of the mounting portion 13 facing the substrate W and the surface of the nozzle 14 facing the substrate W.

[0019] A plurality of holding portions 15 are provided at predetermined intervals on the outer periphery of the mounting portion 13. By placing the substrate W on the holding portions 15, the substrate W is placed in the mounting portion 13 in such a way that a space is formed between the substrate W and the mounting portion 13. The rotation axis 12 of the rotating body base 11 is connected to a rotation drive portion 16 supported on a frame (not shown). The rotating body base 11, the mounting portion 13, and the holding portions 15 rotate together about the rotation axis 12 via the rotation drive portion 16.

[0020] The rotating body base 11 and the mounting portion 13 are preferably made of materials that are resistant to the processing liquids L1 and L2, such as fluoropolymers like polytetrafluoroethylene (PTFE) and polychlorotrifluoroethylene (PCTFE).

[0021] The holding part 15 rotates about an axis parallel to the rotation axis 12 of the rotating body 10 via a drive mechanism (not shown) built into the rotating body 10, thereby moving between a holding position in contact with the periphery of the substrate W to hold the substrate W and a release position in which the substrate W is released by moving away from the periphery of the substrate W.

[0022] (Cooling section) The cooling section 20 supplies cooling gas G to the space between the substrate W and the mounting section 13. The cooling section 20 includes a cooling gas generating section 21, a filter 22, a flow control section 23, and a through hole, i.e., a cooling nozzle 24, formed in the nozzle 14, located outside the frame 60. The cooling gas G supplied to the space between the substrate W and the mounting section 13 is guided to the outer periphery of the mounting section 13 to cool the entire substrate W.

[0023] The cooling gas generation unit 21 stores the coolant and generates the cooling gas G. The coolant is a liquid formed by liquefying the cooling gas G. The cooling gas G is not particularly limited as long as it is a gas that is difficult to react with the material of the substrate W and does not contain moisture; for example, it can be an inert gas such as nitrogen, helium, or argon.

[0024] The cooling gas generating unit 21 includes a storage tank for storing coolant and a vaporization unit for vaporizing the coolant stored in the storage tank. The temperature of the generated cooling gas G is only required to be a temperature that is sufficient to cool the processed liquid L1 to a temperature lower than the freezing point of the processed liquid L1, thus setting it to a supercooled state. Therefore, the temperature of the generated cooling gas G can be set to a temperature lower than the freezing point of the processed liquid L1, for example, it can be set to -170°C.

[0025] The filter 22 is installed in the piping connecting the cooling gas generating unit 21 and the cooling nozzle 24. The filter 22 removes particulate matter and other foreign objects contained in the generated cooling gas G.

[0026] A flow control unit 23 is provided in the piping connecting the cooling gas generation unit 21 and the cooling nozzle 24. The flow control unit 23 controls the flow rate of the cooling gas G supplied to the space between the substrate W and the mounting unit 13. The flow control unit 23 can be, for example, a mass flow controller (MFC). Furthermore, the flow control unit 23 can also indirectly control the flow rate of the cooling gas G by controlling the supply pressure of the cooling gas G. In this case, the flow control unit 23 can be, for example, an automatic pressure controller (APC).

[0027] (First Liquid Supply Department) The first liquid supply unit 30 supplies processing liquid L1 to the surface of the substrate W to be processed. The first liquid supply unit 30 includes a liquid storage unit 31 for storing the processing liquid L1, a supply unit 32 such as a pump, a flow control unit 33 such as a flow control valve, and a liquid nozzle 34 for spraying the processing liquid L1 onto the surface of the substrate W. The liquid storage unit 31 is connected to the liquid nozzle 34 via piping. The supply unit 32 and the flow control unit 33 are provided in the piping connecting the liquid storage unit 31 and the liquid nozzle 34. The liquid storage unit 31, the supply unit 32, and the flow control unit 33 are located outside the frame 60, and the liquid nozzle 34 is located inside the frame 60. The processing liquid L1 is not particularly limited as long as it is a liquid that is unlikely to react with the material of the substrate W and increases in volume upon freezing. For example, the processing liquid L1 can be pure water or ultrapure water, or a liquid with water as its main component.

[0028] The tip of the liquid nozzle 34 faces approximately the center of the surface of the substrate W to be processed, which is held by the holding part 15. The processing liquid L1 sprayed from the liquid nozzle 34 onto the center of the surface to be processed of the substrate W is expanded from the center of the surface to the outer periphery by the centrifugal force generated when the substrate W is rotated, thereby forming a liquid film of a certain thickness on the surface to be processed of the substrate W.

[0029] (Second Liquid Supply Department) The second liquid supply unit 40 supplies processing liquid L2, used to remove the frozen processing liquid L1, to the surface of the substrate W to be processed. The second liquid supply unit 40 includes a liquid storage unit 41 for storing the processing liquid L2, a supply unit 42 such as a pump, and a flow control unit 43 such as a flow control valve. The liquid storage unit 41 is connected to the liquid nozzle 34 of the first liquid supply unit 30 via piping. Therefore, the liquid nozzle 34 sprays the processing liquid L2 onto the surface of the substrate W to be processed. The supply unit 42 and the flow control unit 43 are provided in the piping connecting the liquid storage unit 41 and the liquid nozzle 34. The liquid storage unit 41, the supply unit 42, and the flow control unit 43 are located outside the frame 60. The processing liquid L2 is not particularly limited to any material that is unlikely to react with the material of the substrate W and is unlikely to remain on the substrate W during the drying step described later. For example, the processing liquid L2 can be pure water or ultrapure water, a mixture of water and ethanol, etc. The processing liquid L2 can also be the same liquid as the processing liquid L1. At this time, the second liquid supply unit 40 can be omitted. Moreover, the example shown is that the nozzles for spraying treatment liquid L1 and treatment liquid L2 are also liquid nozzles 34, but the liquid nozzles for spraying treatment liquid L1 and liquid nozzles for spraying treatment liquid L2 can also be provided separately.

[0030] (Frame) The frame 60 is box-shaped and houses various mechanisms, including the rotating body 10, which holds the substrate W, forming a space for processing the substrate W. Furthermore, the frame 60 has a conveying port (not shown) for loading and unloading the substrate W. An air supply unit 70 supplies air 71 from above the frame 60 toward the substrate W. The air supply unit 70 is located on the top surface of the frame 60. Alternatively, the air supply unit 70 may be located on the side of the top surface of the frame 60. The air supply unit 70 may be a component including a fan or other blower and a filter. The filter may be, for example, a high-efficiency particulate air filter (HEPAF). A cover 61 is provided inside the frame 60. The cover 61 blocks the processing liquid L1 or processing liquid L2 that is discharged to the outside of the substrate W due to the rotation of the substrate W. A partition plate 62 is provided inside the frame 60. A partition plate 62 is disposed between the outer surface of the cover 61 and the inner surface of the frame 60. An outlet 63 is provided on the side of the bottom surface of the frame 60. Cooling gas G, air 71, external gas flowing into the frame 60, and processing liquids L1 and L2 are discharged from the outlet 63 to the outside of the frame 60.

[0031] An exhaust pipe 63a is connected to the outlet 63, and an exhaust unit (pump) 64 is connected to the exhaust pipe 63a to discharge cooling gas G, air 71, and external gas flowing into the frame 60. In addition, an exhaust pipe 63b is also connected to the outlet 63 to discharge processing liquid L1 and processing liquid L2.

[0032] [1-3. Structure of the detection section and the removal section] In the substrate processing apparatus 1 of this embodiment, which has the structure described above, a detection unit 80 and a removal unit 90 are provided to further suppress the situation where droplets D generated by condensation remain on the surface of the rotating body 10 facing the substrate W. Details are described below.

[0033] (Testing Department) After the substrate W is cleaned and removed, the detection unit 80 detects the droplets D generated on the opposing surfaces of the rotating body 10 due to condensation. The detection unit 80 includes a sensor unit 81 and a moving mechanism 82.

[0034] The sensor unit 81 is configured to be moved by the moving mechanism 82 to a position above the opposing surface of the rotating body 10, moving from the outside to the inside of the opposing surface of the rotating body 10 as shown by the arrow in FIG3, to capture the entire opposing surface of the rotating body 10. For example, an infrared (IR) camera or a charge-coupled device (CCD) camera can be used as the sensor unit 81. In this embodiment, the sensor unit 81 performs still image capture while the rotation of the rotating body 10 is stopped, thereby detecting the droplet D. Alternatively, the sensor unit 81 can be pre-fixed above the opposing surface of the rotating body 10, and dynamic image capture can be performed while the rotating body 10 is rotating, thereby detecting the droplet D. The moving mechanism 82 moves the sensor unit 81 between a standby position offset from above the opposing surface of the rotating body 10 and a capture position where images are taken from above the opposing surface of the rotating body 10. The moving mechanism 82 includes a rotating support 82a for moving the sensor unit 81 and an arm 82b for supporting the sensor unit 81. The moving mechanism 82 moves the sensor unit 81 by rotating the arm 82b in the horizontal direction through the rotating support 82a.

[0035] (Removal section) The removal unit 90 removes droplets D remaining on the opposing surfaces of the rotating body 10 by blowing out gas A. The removal unit 90 has a blowing unit 91 and a moving mechanism 92. The blowing unit 91 has a pipe 91a connected to a gas supply device (not shown), and the front end of the pipe 91a forms a nozzle 91b facing the rotating body 10. The gas A blown out by the blowing unit 91 is a gas at room temperature or above without moisture, such as N2 gas or clean air.

[0036] The moving mechanism 92 moves the nozzle 91b between a standby position offset from above the opposing surface of the rotating body 10 and a blowing position where gas A is sprayed downwards from above the opposing surface of the rotating body 10. Furthermore, in the blowing position, the moving mechanism 92 causes the nozzle 91b, which sprays gas A, to oscillate. The moving mechanism 92 has a rotating support portion 92a for moving the nozzle 91b and an arm portion 92b for supporting the nozzle 91b. The moving mechanism 92 moves the nozzle 91b by rotating the arm portion 92b horizontally via the rotating support portion 92a.

[0037] (Control Department) The control unit 100 controls each part of the substrate processing apparatus 1. To realize the various functions of the substrate processing apparatus 1, the control unit 100 includes a processor for executing programs, a storage unit for storing various information such as programs and operating conditions, and drive circuits for driving each component. The control unit 100 includes: a control unit for performing various controls necessary to clean the surface of the substrate W placed on the mounting unit 13; and a control unit for performing various controls necessary to remove droplets D remaining on the opposing surfaces of the rotating body 10.

[0038] As a control unit for cleaning the surface to be processed on the substrate W, the control unit 100 includes: a mechanism control unit 110 for controlling the driving of the rotation drive unit 16, the holding unit 15, etc.; and a supply control unit 120 for controlling the supply of processing liquid L1 and processing liquid L2 and the supply of cooling gas G.

[0039] The control unit 100 also includes a detection control unit 130, a determination unit 140, and a removal control unit 150, which serve as control units for removing droplets D remaining on the opposing surfaces of the rotating body 10.

[0040] To detect droplets D remaining on the opposing surfaces of the rotating body 10, the detection control unit 130 moves the sensor unit 81 and controls the setting of the imaging conditions and the timing of the imaging in the sensor unit 81. When detecting droplets D, the detection control unit 130 controls the moving mechanism 82 to move the sensor unit 81 from the standby position to the imaging position. After the sensor unit 81 reaches the imaging position, the detection control unit 130 outputs an imaging command to the sensor unit 81, thereby imaging the opposing surfaces of the rotating body 10.

[0041] The determination unit 140 determines whether there is any residual droplet D on the surface of the rotating body 10 facing the substrate W. The determination unit 140 performs image processing (e.g., binarization) on the image captured by the sensor unit 81, processing it so that the area of ​​droplet D can be distinguished from other areas, thereby determining whether there is residual droplet D on the facing surface of the rotating body 10. For example, in the image captured by the sensor unit 81, if the ratio of the area of ​​droplet D to the area of ​​the facing surface of the rotating body 10 exceeds a threshold, or if the ratio of the area not covered by droplet D to the area of ​​the facing surface of the rotating body 10 is below a threshold, it is determined that there is residual droplet D.

[0042] To remove droplets D remaining on the opposing surfaces of the rotating body 10, the removal control unit 150 moves the nozzle 91b and controls the amount and timing of gas A being blown out of the nozzle 91b. When removing residual droplets D, the removal control unit 150 controls the moving mechanism 92 to move the nozzle 91b from the standby position to the blowing position. After the nozzle 91b reaches the blowing position, the removal control unit 150 ejects gas A from the nozzle 91b at a predetermined flow rate. In this embodiment, when the determination unit 140 determines that droplets D remain, the removal control unit 150 removes the droplets D via the removal unit 90.

[0043] [1-4. Operation of the First Embodiment] In addition to Figures 1 to 3, the operation of the substrate processing apparatus 1 of this embodiment described above will also be explained using the flowchart in Figure 4 and Figures 5 to 7. During the explanation, the operation of cleaning the surface of the substrate W to be processed (steps S01 to S06) and the operation of removing droplets D remaining on the opposing surface of the rotating body 10 (steps S07 to S14) will be explained separately.

[0044] (The action of cleaning the surface of substrate W to be processed) As shown in Figure 1, before the substrate W is moved into the frame 60, the detection unit 80 and the removal unit 90 are in a standby position. In this state, the substrate W, mounted on the hand of the transport robot, is moved above the rotating body 10 and placed on the mounting unit 13. As shown in Figure 2, the periphery of the substrate W placed on the mounting unit 13 is held by a plurality of holding parts 15 (step S01). At this time, the substrate W is positioned so that its center is aligned with the axis of rotation of the rotating body 10.

[0045] After the substrate W is held in the holding part 15, a freezing and cleaning step is performed as shown in FIG4. The freezing and cleaning step includes a preparation step, a cooling step (overcooling step + freezing step), a thawing step, and a drying step.

[0046] In the preparatory step (step S02), the control unit 100 controls the supply unit 32 and the flow control unit 33 to supply the processing liquid L1 to the surface of the substrate W to be processed at a predetermined flow rate. The control unit 100 controls the flow control unit 23 to supply cooling gas G to the space between the substrate W and the mounting unit 13 from the side of the substrate W opposite to the surface to be processed (the side of the rotating body 10) at a predetermined flow rate. The mechanism control unit 110 controls the rotation drive unit 16 to rotate the substrate W at a predetermined speed.

[0047] Here, when the substrate W cools down due to the supply of cooling gas G through the cooling section 20, frost containing foreign matter from the environment within the frame 60 may adhere to the substrate W, causing contamination. In the preparatory step, cooling gas G is supplied from the side of the substrate W opposite to the surface to be processed, and processing liquid L1 is continuously supplied to the surface to be processed. This ensures uniform cooling of the substrate W while preventing frost from adhering to the surface to be processed. For example, the rotational speed of the substrate W can be set to approximately 100 rpm, the flow rate of the processing liquid L1 to approximately 0.3 L / min, the flow rate of the cooling gas G to approximately 170 NL / min, and the preparatory step time to approximately 1800 seconds.

[0048] In the cooling step (step S03) (overcooling step + freezing step), the supply of the processing liquid L1 supplied in the preparation step is stopped, and the rotation speed of the substrate W is set to approximately 30 rpm. This rotation speed is such that the processing liquid L1 supplied to the center of the surface to be processed extends to the outer periphery of the surface to be processed on the substrate W, forming a liquid film of uniform thickness on the substrate W and maintaining it. That is, the control unit 100 rotates the substrate W at a speed less than that in the preparation step. Moreover, the thickness of the liquid film of the processing liquid L1 at this time can be set to a thickness that covers the protrusions of the unevenness formed on the surface to be processed on the substrate W. Moreover, the flow rate of the cooling gas G is maintained at 170 NL / min. By continuously supplying the cooling gas G to the space between the substrate W and the mounting unit 13 as described above, the temperature of the liquid film (processing liquid L1) formed on the surface to be processed on the substrate W decreases compared to the temperature in the preparation step, and the liquid film becomes overcooled (overcooling step). Even after the liquid film becomes supercooled, cooling gas G is continuously supplied to the space between the substrate W and the mounting section 13 through the cooling section 20. By continuously supplying cooling gas G, the temperature of the liquid film on the surface to be processed on the substrate W further decreases, and at least a portion of the liquid film freezes (freezing step). As a result, foreign matter adhering to the surface to be processed on the substrate W is separated from the surface to be processed due to the expansion of the liquid film and is trapped inside the frozen liquid film.

[0049] In the defrosting step (step S04), the control unit 100 controls the supply unit 42 and the flow control unit 43 to supply the processing liquid L2 to the surface of the substrate W to be processed at a predetermined flow rate. Furthermore, the control unit 100 controls the flow control unit 23 to stop the supply of cooling gas G.

[0050] Furthermore, the control unit 100 controls the rotation drive unit 16 to increase the rotational speed of the substrate W. If the rotational speed of the substrate W increases, centrifugal force can be used to fling out the processing liquid L1 and the ice formed by freezing the processing liquid L1, thereby removing them from the substrate W. Therefore, the processing liquid L1 and the ice formed by freezing the processing liquid L1 are easily discharged from the substrate W. Moreover, at this time, foreign matter separated from the processed surface of the substrate W is also discharged along with the processing liquid L1 and the ice formed by freezing the processing liquid L1.

[0051] In the drying step (step S05), the control unit 100 controls the supply unit 42 and the flow control unit 43 to stop the supply of the processing liquid L2. Furthermore, the control unit 100 controls the rotation drive unit 16 to further increase the rotational speed of the substrate W. If the rotational speed of the substrate W increases, the substrate W can be dried quickly. Additionally, the rotational speed of the substrate W is not particularly limited as long as drying is possible. By configuring it as described above, the substrate W can be cleaned.

[0052] During substrate release / removal (step S06), the mechanism control unit 110 stops the rotation of the substrate W. Then, the hand of the transfer robot is inserted under the substrate W, the holding unit 15 releases the holding of the substrate W, and the substrate W is removed by the hand of the transfer robot.

[0053] (An action used to remove droplets remaining on the opposing surfaces of the rotating bodies) Next, the operation for removing droplets D remaining on the opposing surfaces of the rotating body 10 will be explained. As mentioned earlier, during the preparation or cooling step, cooling gas G is supplied to the space between the substrate W and the mounting portion 13. Subsequently, even after the thawing and drying steps, the temperature of the rotating body 10, including the mounting portion 13, remains below room temperature due to the influence of the cooling gas G. For example, in this state, when the conveying port of the frame 60 is opened to remove the substrate W and external gas flows in, the room-temperature external gas that flows in becomes cold due to the cooling of the rotating body 10. When the room-temperature external gas becomes cold due to the cooling of the rotating body 10, as shown in FIG. 5, droplets D caused by condensation are generated on the opposing surfaces of the rotating body 10. The substrate processing apparatus 1 removes the droplets D generated on the opposing surfaces of the rotating body 10 through steps after step S07.

[0054] In the imaging steps (steps S07 to S09), images are taken of the opposing surfaces of the rotating body 10. When the substrate W is removed from the frame 60, the detection control unit 130 controls the moving mechanism 82 to move the sensor unit 81 from the standby position to the imaging position, as shown in FIG6 (step S07). The imaging position can be one location above the rotating body 10 or multiple locations. Hereinafter, we will describe the imaging position as one location.

[0055] After the sensor unit 81 moves to the shooting position, the detection control unit 130 performs a photograph of the opposing surface of the rotating body 10 using the sensor unit 81 under predetermined conditions (step S08). The photographing result is stored in the storage unit within the control unit 100. After the photographing, the detection control unit 130 moves the sensor unit 81 from the shooting position to the standby position (step S09).

[0056] In the image processing step (step S10), the determination unit 140 performs image processing on the image captured by the sensor unit 81. The determination unit 140 processes the captured image to make the area of ​​the droplet D distinguishable from other areas. The processed image is stored in the storage unit within the control unit 100.

[0057] In the determination step, the determination unit 140 determines whether there is a droplet D residue on the opposing surface of the rotating body 10 based on the image processed by the image processing (step S11). The determination unit 140 determines that there is a droplet D residue if the ratio of the area of ​​the droplet D in the image to the area of ​​the opposing surface of the rotating body 10 exceeds a threshold. Alternatively, the determination unit 140 may determine that there is a droplet D residue even if there is only one droplet D in the image.

[0058] If it is determined that there is a droplet D remaining on the opposing surface of the rotating body 10 (as determined in step S11), then a removal step for removing the droplet D is performed (steps S12 to S14). The removal control unit 150 controls the moving mechanism 92 to move the nozzle 91b from the standby position to the blowing position (step S12).

[0059] After the nozzle 91b moves to the blowing position, as shown in FIG7, the removal control unit 150 causes gas A to be ejected from the blowing unit 91 at a predetermined flow rate (step S13). Through the gas A ejected from the blowing unit 91, the droplets D remaining on the opposing surfaces of the rotating body 10 are blown away from the rotating body 10 and removed. During the ejection of gas A from the blowing unit 91, the mechanism control unit 110 controls the rotation drive unit 16 to rotate the rotating body 10, and the removal control unit 150 controls the moving mechanism 92 to swing the nozzle 91b. Thus, droplets D remaining on the entire opposing surface of the rotating body 10 can be blown away from the rotating body 10 and removed. Furthermore, when using a low-humidity gas such as dry air as gas A, the droplets D can be dried and removed instead of simply using the blowing pressure of gas A to blow them away.

[0060] After the removal of droplet D, the mechanism control unit 110 stops the rotation of the rotating body 10, and the removal control unit 150 stops the ejection of gas A from the blowing unit 91, causing the nozzle 91b to move from the blowing position to the standby position (step S14). After the removal of droplet D, if there is a substrate W that is to be processed next, the process is transferred to the loading of substrate W (step S15 No). If there is no substrate W that is to be processed next, the process ends (step S15 Yes).

[0061] If, in the determination step, it is determined that there is no residual droplet D (No in step S11), and there is a substrate W that is to be processed next (No in step S15), then the process proceeds to the loading of substrate W (step S01). If there is no substrate W that is to be processed next, then the process ends (Yes in step S15).

[0062] [1-5. Effects of the First Embodiment] (1) The substrate processing apparatus 1 of this embodiment as described above includes: a rotating body 10, including a mounting section 13, which mounts a substrate W having a surface to be processed on one side, and mounts the substrate W in such a way that a space is maintained between the surfaces of the substrate W opposite to the surface to be processed; a rotation drive section 16, which rotates the rotating body 10; a liquid supply section 30 and a liquid supply section 40, which supply processing liquid L1 and processing liquid L2 to the surface to be processed of the substrate W; a cooling section 20, which supplies cooling gas G to the space between the substrate W and the mounting section 13; and a removal section 90, which removes droplets D from the surface of the rotating body 10 facing the substrate W.

[0063] Therefore, in the substrate processing apparatus 1 of this embodiment, the removal unit 90 can remove droplets D from the surface of the rotating body 10 facing the substrate W. As a result, it is possible to suppress the situation where droplets D remain on the facing surface of the rotating body 10, and to prevent droplets D from adhering to the substrate W to be processed subsequently, thereby improving the cleanliness of the substrate W.

[0064] (2) In this embodiment, after the substrate W is removed, the droplets D are removed when the substrate W is not placed on the mounting section 13. Here, one of the reasons why the droplets D condense on the opposing surface of the rotating body 10 is that the ambient temperature external gas flowing into the frame 60 is cooled by the cooling gas G used to clean the surface of the substrate W being processed. When the substrate W is placed on the mounting section 13, the transfer port of the substrate W in the frame 60 is closed, and the inflow of external gas is small, so the amount of droplets D generated by condensation on the opposing surface of the rotating body 10 is small. However, when the cleaning process using the freeze cleaning method is completed and the substrate W is moved to the outside of the frame 60, external gas flows into the frame 60. The inflowing external gas is cooled by the rotating body 10 cooled by the cooling gas G, thereby leaving a large number of droplets D generated by condensation on the opposing surface of the rotating body 10.

[0065] Therefore, in this embodiment, the removal of droplets D is not performed by the removal unit 90 while the substrate W is mounted, but rather when the substrate W is not mounted on the mounting portion 13, where droplets D are prone to form. Thus, in this embodiment, the likelihood of droplets D forming on the opposing surfaces of the rotating body 10 is predicted in advance, and the removal unit 90 removes the droplets D remaining on the opposing surfaces of the rotating body 10. This minimizes the number of steps required to prevent droplets D from adhering to the substrate W to be processed subsequently, thereby improving the cleanliness of the substrate W.

[0066] Meanwhile, in this embodiment, the detection unit 80 detects the droplet D or the removal unit 90 removes the droplet D when the substrate W is not mounted on the mounting portion 13. Therefore, the detection or removal of the droplet D is not hindered by the substrate W, thus improving the detection accuracy or removal efficiency of the droplet D.

[0067] (3) In this embodiment, the system includes: a detection unit 80 for detecting droplets D on the opposing surfaces of the rotating body 10; and a control unit 100 for removing droplets D by a removal unit 90 based on the detection result obtained by the detection unit 80. Therefore, by removing droplets D when it is determined that there are droplets D remaining on the opposing surfaces of the rotating body 10, the efficiency of the droplet D removal process can be improved.

[0068] (4) The removal unit 90 removes the droplets D on the opposing surfaces of the rotating body 10 by ejecting gas A onto the droplets D. Therefore, the droplets D on the opposing surfaces of the rotating body 10 can be removed in a short time. Furthermore, the droplets D and particles contained within them can be removed simultaneously.

[0069] The temperature of the gas A ejected by the removal unit 90 is above room temperature. Therefore, the ejection of gas A removes droplets D from the opposing surface of the rotating body 10, and the temperature of the opposing surface of the rotating body 10 is above room temperature. Thus, after the droplets D are removed by the removal unit 90, the environment around the rotating body 10 cools due to the opposing surface of the rotating body 10, thereby preventing the re-generation of droplets D on the opposing surface of the rotating body 10 until the subsequent substrate W is brought in.

[0070] [2. Other Implementation Methods] The embodiments of the present invention have been illustrated above. However, the embodiments of the present invention are not limited to these descriptions. Embodiments made by those skilled in the art with appropriate design modifications to the foregoing embodiments, as long as they possess the features of the present invention, are included within the scope of the present invention. For example, the shape, size, quantity, and arrangement of the components included in the substrate processing apparatus 1 are not limited to the illustrated contents and can be appropriately modified.

[0071] (1) In the first embodiment, the removal unit 90 removes the droplet D by blowing gas A onto it. However, any mechanism capable of removing the droplet D is acceptable; for example, the droplet D can be removed by heating it. FIG8 is a diagram showing the structure of the removal unit 90 in a modified example of the first embodiment. As shown in FIG8, the removal unit 90 replaces the blowing unit 91 that blows out gas A and includes a heater 93. Furthermore, the removal unit 90 has a moving mechanism 92 that can move the heater 93 to a standby position offset from above the rotating body 10 and a heating position facing the rotating body 10. Moreover, the moving mechanism 92 can also be configured such that the heater 93 can move up and down along the extension direction of the rotation axis 12 of the rotating body 10. The heater 93 generates heat by energizing it. The heater 93 can be, for example, a light-emitting diode (LED), a halogen lamp, a quartz heater, etc.

[0072] The removal unit 90 removes droplets D by heating them with heat from the heater 93, causing them to evaporate. During the heating period of the heater 93, the mechanism control unit 110 controls the rotation drive unit 16 to rotate the rotating body 10, and the removal control unit 150 controls the movement mechanism 92 to oscillate the heater 93. This allows heating of the entire facing surface of the rotating body 10, thereby removing droplets D remaining on the facing surface. Furthermore, by heating droplets D with the heater 93, a wide range of droplets D, rather than localized ones, can be removed, thus reducing omissions. Moreover, by setting the temperature of the heater 93 to the minimum required to remove droplets D, overheating of the facing surface of the rotating body 10 can be avoided. This allows the time required to cool the facing surface of the rotating body 10 before the subsequent substrate W is brought in to a necessary minimum. Furthermore, the diameter of the heater 93 can be larger than the outer diameter of the mounting unit 13. At this point, the rotation of the rotating body 10 and the oscillation of the heater 93 during the heating of the droplet D are omitted. As a result, the entire opposing surface of the rotating body 10 can be heated in a simple manner, thereby effectively removing the droplet D remaining on the opposing surface.

[0073] (2) Furthermore, as shown in FIG9, the removal section 90 can replace the blowing section 91 of the blowing gas A to rotate the rotating body 10, thereby removing the droplets D by its centrifugal force. At this time, the nozzle 14 is rotatably provided. In addition to the rotating body base 11, the mounting section 13 and the holding section 15 of the rotating body 10, the nozzle 14 is also rotated. Therefore, the droplets D on the opposing surfaces of the rotating body 10 move to the outer peripheral side and are discharged from the end of the mounting section 13 to the outside of the rotating body 10. With this structure, the processing steps can be simplified.

[0074] (3) As shown in Figure 10, a dispersion plate 25 may also be provided on the exhaust side of the cooling gas G from the cooling nozzle 24. The dispersion plate 25 disperses the cooling gas G supplied from the cooling nozzle 24. As a result, the entire substrate W can be cooled uniformly. As shown in Figure 11, the dispersion plate 25 is a disc-shaped component with holes 25a in multiple locations. The dispersion plate 25 is fixed to the nozzle 14 via a support member 26.

[0075] Figure 12 is a schematic diagram showing the case where droplets D remain after the substrate W is removed from the substrate processing apparatus 1 equipped with the dispersion plate 25. The rotating body 10 and the dispersion plate 25 are cooled by the cooling gas G supplied during the cleaning of the substrate W. For example, in this state, when the substrate W conveying port of the frame 60 is opened for removing the substrate W and external gas flows in, the incoming ambient temperature external gas is cooled by the rotating body 10 and the dispersion plate 25. Therefore, as shown in Figure 12, droplets D caused by condensation are generated on the opposing surface of the dispersion plate 25 (the surface of the dispersion plate 25 facing the substrate W) and the opposing surface of the rotating body 10. Therefore, after the substrate W is removed, if the determination unit 140 determines that droplets D remain on the opposing surface of the rotating body 10 or the dispersion plate 25, the droplets D are removed by blowing out the gas A from the blowing section 91 of the removal unit 90, as shown in Figure 13. Furthermore, the removal section 90 can replace the blowing section 91 that blows out gas A, causing the rotating body 10 to rotate, thereby removing droplets D by its centrifugal force. At this time, the nozzle 14 is rotatably provided. By rotating the nozzle 14, the dispersion plate 25 supported on the nozzle 14 via the support member 26 can be rotated, thereby removing droplets D remaining on the surface of the dispersion plate 25 facing the substrate W.

[0076] (4) After the removal unit 90 removes the droplet D, the detection unit 80 can detect the droplet D again. When the droplet D is detected, the removal unit 90 can remove the droplet D again. Alternatively, the detection unit 80 can be omitted from detecting the droplet D, but the removal unit 90 must be used to remove the droplet D after cleaning the substrate W.

[0077] (5) In the case where an image sensor or other detection unit is provided to detect the freezing state of the processing liquid L1 on the surface of the substrate W to be processed, the image sensor or other detection unit may also be used as the detection unit for the droplet D.

[0078] (6) In addition to detecting the droplet D, the detection unit 80 can also detect the state of the processing liquid L1 supplied to the processed surface of the substrate W. Furthermore, in addition to controlling the removal unit 90 to remove the droplet D, the control unit 100 can also control the flow rate of the cooling gas G supplied by the cooling unit 20 based on the state of the processing liquid L1 detected by the detection unit 80. That is, by combining the detection and removal control of the droplet D with the detection of the processing liquid L1 and the flow rate control of the cooling gas G as a means required for image processing or flow control, it is possible to reduce the number of components in the substrate processing apparatus 1 or to miniaturize the substrate processing apparatus 1.

[0079] (7) Furthermore, the substrate W with the irregular surface formed thereon is used as the processing object in the first embodiment, but it can also be applied to a substrate W without the irregular surface formed thereon. In this case, the processing surface of the substrate W can be the surface that needs to be cleaned.

[0080] 1: Substrate processing device 10: Solid of Revolution 11: Rotating base 12: Rotation axis 13: Mounting section 14: Sprayer Head 15: Maintaining section 16: Rotary drive unit 20: Cooling section 21: Cooling Gas Generation Section 22: Filter 23, 33, 43: Flow Control Department 24: Cooling nozzle 25: Dispersion plate 25a: Hole 26: Supporting components 30: First Liquid Supply Department 31, 41: Liquid storage section 32, 42: Supply Department 34: Liquid Nozzle 40: Second Liquid Supply Department 60: Frame 61: Cover 62: Divider 63: Discharge outlet 63a: Exhaust pipe 63b: Discharge pipe 64: Exhaust section 70: Air Supply Department 71: Air 80: Testing Department 81: Sensor Department 82, 92: Moving mechanism 82a, 92a: Rotary support section 82b, 92b: Arm 90: Removal section 91:Blow out part 91a:Piping 91b: Nozzle 93: Heater 100: Control Department 110: Mechanism Control Department 120: Supply Control Department 130: Inspection and Control Department 140: Judgment Department 150: Remove control unit A: Gas D: Droplet G: Cooling gas L1, L2: Treatment fluid W: substrate S01~S15: Steps

Claims

1. A substrate processing apparatus, comprising: A rotating body includes a mounting section that mounts a substrate having a surface to be processed, and the substrate is mounted in such a way that a space is maintained between the substrate and a surface opposite to the surface to be processed; a rotation drive section that rotates the rotating body; a liquid supply section that supplies liquid to the surface to be processed of the substrate; and a cooling section that supplies cooling gas to the space between the substrate and the mounting section. The rotating body also includes a removal section for removing droplets from the surface of the rotating body facing the substrate; the removal section removes the droplets when the substrate is not mounted on the mounting section.

2. The substrate processing apparatus as claimed in claim 1, comprising: The detection unit detects the droplets; The control unit, based on the detection result obtained by the detection unit, removes the droplets via the removal unit.

3. The substrate processing apparatus as claimed in claim 2, wherein, The detection unit detects the droplet when the substrate is not placed on the mounting unit.

4. The substrate processing apparatus as claimed in claim 2, wherein, In addition to detecting the droplets, the detection unit also detects the state of the liquid supplied to the processed surface of the substrate. In addition to controlling the removal unit to remove the droplets, the control unit also controls the flow rate of the cooling gas supplied by the cooling unit based on the state of the liquid detected by the detection unit.

5. The substrate processing apparatus as claimed in claim 1, wherein, The cooling unit includes: a cooling nozzle capable of supplying the cooling gas; A dispersion plate is disposed on the cooling gas discharge side of the cooling nozzle, facing the substrate, and the removal section removes the droplets from the surface of the dispersion plate facing the substrate.

6. The substrate processing apparatus according to any one of claims 1 to 5, wherein, The removal unit removes the droplets by spraying gas into them.

7. The substrate processing apparatus as claimed in claim 6, wherein, The temperature of the gas ejected by the removal unit is above room temperature.

8. The substrate processing apparatus according to any one of claims 1 to 5, wherein, The removal section removes the droplets by heating them.

9. The substrate processing apparatus according to any one of claims 1 to 4, wherein, The removal section removes the droplets by rotating the rotating body.

10. The substrate processing apparatus as claimed in claim 5, wherein, The removal section removes the droplets by rotating the rotating body and the dispersing plate.

11. A substrate processing apparatus, comprising: A rotating body includes a mounting section that mounts a substrate having a surface to be processed, and the substrate is mounted in such a way that a space is maintained between the substrate and a surface opposite to the surface to be processed; a rotation drive section that rotates the rotating body; a liquid supply section that supplies liquid to the surface to be processed of the substrate; and a cooling section that supplies cooling gas to the space between the substrate and the mounting section. The rotating body includes a removal section that removes droplets from the surface of the rotating body facing the substrate. The removal section removes the droplets by spraying gas onto them. The temperature of the gas sprayed by the removal section is above room temperature.

12. A substrate processing apparatus, comprising: A rotating body includes a mounting section that mounts a substrate having a surface to be processed, and the substrate is mounted in such a way that a space is maintained between the substrate and a surface opposite to the surface to be processed; a rotation drive section that rotates the rotating body; a liquid supply section that supplies liquid to the surface to be processed of the substrate; and a cooling section that supplies cooling gas to the space between the substrate and the mounting section. The rotating body includes a removal section that removes droplets from the surface of the rotating body facing the substrate; the removal section removes the droplets by heating them.

13. A substrate processing apparatus, comprising: A rotating body includes a mounting section that mounts a substrate having a surface to be processed, and the substrate is mounted in such a way that a space is maintained between the substrate and a surface opposite to the surface to be processed; a rotation drive section that rotates the rotating body; a liquid supply section that supplies liquid to the surface to be processed of the substrate; and a cooling section that supplies cooling gas to the space between the substrate and the mounting section. The rotating body includes a removal section that removes droplets from the surface of the rotating body facing the substrate. The removal section removes the droplets by rotating the rotating body.

14. A substrate processing method comprising: placing a substrate on a mounting portion; rotating a rotating body including the mounting portion while the substrate is mounted; supplying liquid to a surface of the substrate opposite to the mounting portion side, i.e., a surface to be processed; supplying cooling gas to the space between the substrate and the mounting portion; freezing the liquid supplied to the surface to be processed; and removing droplets from the rotating body on the surface facing the substrate while the mounting portion is not mounted.

Images