Substrate processing apparatus and substrate processing method

Abstract

To provide a substrate processing apparatus and a substrate processing method, which can suppress the generation of mist due to the collision of processing liquid staying on the inner wall surface of a cup with newly scattered processing liquid, thereby preventing the mist from adhering to a substrate.SOLUTION: A substrate processing apparatus includes: a holding unit 11 that holds a substrate W; a driving unit 12 that is provided in the holding unit 11 and rotates the substrate W together with the holding unit 11; a supply unit 13 that supplies processing liquid to a target surface of the substrate W; a first cup C1 provided to surround the substrate W; a second cup C2 that is provided to surround the first cup C1 and has an inner wall surface having a property different from that of the first cup C1; and a movement control unit that moves the first cup C1 and the second cup C2 such that the processing liquid scattered from the substrate W is received either on the inner wall surface of the first cup C1 or on the inner wall surface of the second cup C2.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a substrate processing apparatus and a substrate processing method. [Background technology]

[0002] Conventionally, there has been known a single-wafer type substrate processing apparatus that supplies a processing liquid to a processing surface of a substrate such as a semiconductor wafer while rotating the substrate, and performs an etching process, a cleaning process, or the like. The substrate processing apparatus includes a substrate holding unit, a rotation drive unit, a processing liquid supply unit, and a processing liquid recovery unit. The substrate holding unit holds an edge of the substrate by a chuck pin provided on a table. The rotation drive unit rotates the substrate together with the substrate holding unit. The processing liquid supply unit ejects the processing liquid toward the processing surface of the rotating substrate. The processing liquid recovery unit recovers the processing liquid scattered from the rotating substrate. Specifically, the scattered processing liquid is received by a cup provided to surround the rotation drive unit. The processing liquid flows downward along the inner wall surface of the cup, and is recovered from a pipe provided at the bottom of the cup and reused.

[0003] Substrate processing is generally performed by switching between multiple types of processing liquids. For this reason, a technology is known for a cup for receiving the processing liquid, which can be moved up and down to change the height so as to receive each type of processing liquid splashed from the substrate, as described in Patent Document 1, for example. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2009-110985 A Summary of the Invention [Problem to be solved by the invention]

[0005] When substrates are processed using multiple types of processing liquids, the processing liquids may remain on the inner wall surface of the cup due to differences in the viscosities of the processing liquids, for example. When newly scattered processing liquid collides with the processing liquid remaining inside the cup, the processing liquid bursts into mist. This mist of processing liquid may scatter outside the cup or bounce back toward the substrate and adhere to it. In particular, there is a problem that the mist of processing liquid that has adhered to the substrate may dry out, which may lead to product defects.

[0006] The present invention aims to provide a substrate processing apparatus and a substrate processing method that can suppress the generation of mist caused by collision of newly scattered processing liquid with processing liquid remaining on the inner wall surface of a cup, and prevent the mist from adhering to a substrate. [Means for solving the problem]

[0007] The substrate processing apparatus of the present invention includes a holder for holding a substrate, a drive unit provided on the holder for rotating the substrate together with the holder, a supply unit for supplying a processing liquid to a processing surface of the substrate in order to process the substrate, and a processing unit provided to surround the substrate. The inner wall surface is either hydrophilic or hydrophobic. a first cup having an inner wall surface provided to surround the first cup; is either hydrophilic or hydrophobic The apparatus includes a second cup, and a movement control unit that moves the first cup and the second cup to cause the processing liquid splashed from the substrate to be received on either the inner wall surface of the first cup or the inner wall surface of the second cup.

[0008] The substrate processing method of the present invention includes steps of holding a substrate, rotating the held substrate, supplying a processing liquid to a processing surface of the substrate in order to process the substrate, and providing a processing liquid to a processing chamber provided to surround the substrate. The inner wall surface is either hydrophilic or hydrophobic. The first cup 、 and an inner wall surface of the first cup. is either hydrophilic or hydrophobic and moving a second cup so that the processing liquid splashed from the substrate is received on one of an inner wall surface of the first cup or an inner wall surface of the second cup. Effect of the Invention

[0009] The substrate processing apparatus and substrate processing method of the present invention suppress the generation of mist caused by newly scattered processing liquid colliding with processing liquid remaining on the inner wall surface of the cup, and can prevent the mist from adhering to the substrate. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram showing a substrate processing apparatus according to an embodiment. [Diagram 2] FIG. 2 is a view showing a state in which a first cup has been moved downward in the substrate processing apparatus of the embodiment. [Diagram 3] FIG. 2 is a diagram showing a control unit according to the embodiment. [Figure 4] 4 is a flowchart showing the operation of the substrate processing apparatus according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] (composition) Hereinafter, an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the substrate processing apparatus 1 of this embodiment is a single-wafer type substrate processing apparatus that supplies a processing liquid to a surface (hereinafter, also referred to as a surface to be processed) of a substrate W such as a semiconductor wafer, and performs an etching process or a cleaning process. The substrate processing apparatus 1 includes a holder 11 that holds the substrate W, a drive unit 12 that rotates the substrate W together with the holder 11, a supply unit 13 that supplies the processing liquid to the substrate W, a discharge unit 14 that discharges the processing liquid supplied to the substrate W, and a detection unit 15 that detects the processing liquid that has splashed from the substrate W and been received and bounced back by a cup C described later. The substrate processing apparatus 1 includes a control unit 8 described later, and is controlled by the control unit 8.

[0012] The holder 11 includes a table T and a chuck pin P provided on the top surface of the table T. The table T is, for example, a cylindrical stage. The chuck pin P is provided on the top surface of the table T and holds the edge of the substrate W.

[0013] The drive unit 12 is provided in the holder 11. The drive unit 12 rotates the holder 11 and the substrate W held by the holder 11 around an axis perpendicular to the substrate W by a drive source such as a motor. The rotation speed of the substrate W is controlled by the control unit 8.

[0014] The supply units 13 are nozzles provided opposite both sides of the substrate W and discharge the processing liquid toward both sides of the substrate W rotated by the drive unit 12. One or more supply units 13 may be provided for each side of the substrate W, but the following description will be given assuming that one supply unit 13 is provided for each side. The nozzle facing the surface (front side) of the substrate W facing the same direction as the top surface of the table T is connected to a nozzle moving mechanism (not shown) and is provided so as to be able to reciprocate between a discharge position facing the center of the front surface of the substrate W and a standby position radially outward from the discharge position. The nozzle facing the surface (back side) of the substrate W facing the top surface of the table T is provided in a hollow portion (not shown) provided at the center of the table T. This nozzle is not affected by the drive unit 12 and is provided immovably so as not to rotate together with the table T. The movement of the nozzle and the supply amount of the processing liquid are controlled by the control unit 8.

[0015] In this embodiment, the processing liquid used is Buffered Hydrogen Fluoride (BHF), DeIonized Water (DIW), ozone water, or Hydrogen Fluoride (HF).

[0016] BHF is an aqueous solution obtained by mixing an aqueous solution of high-purity hydrofluoric acid and an aqueous solution of ammonium fluoride. BHF is used as an etching solution for removing oxide films formed on the surface of the substrate W and metal impurities attached to the surface (processing surface) of the substrate W. In addition, BHF has high viscosity.

[0017] DIW is pure water that contains almost no impurities. DIW is used as a rinsing liquid for removing the etching liquid from the substrate W. DIW also has low viscosity.

[0018] Ozone water is an aqueous solution of ozone. Ozone water is used to form an oxide film on the surface of the substrate W where Si is exposed after the oxide film has been removed by BHF or HF. Ozone water has low viscosity.

[0019] HF is an aqueous solution of hydrofluoric acid. Like BHF, HF is used as an etching solution for removing oxide films formed on the surface of the substrate W and metal impurities adhering to the surface of the substrate W. HF also has low viscosity.

[0020] The discharge unit 14 is a container that receives and discharges the processing liquid splashed from the surface of the substrate W. The discharge unit 14 is provided so as to surround the substrate W held by the drive unit 12, and includes a cup C that receives the processing liquid splashed from the surface of the substrate W, and a pipe D that is provided at the bottom of the cup C and discharges the processing liquid that has trickled down the inner wall surface of the cup C.

[0021] The cup C includes a first cup C1 and a second cup C2. The first cup C1 and the second cup C2 are cylindrical with an opening that exposes the face (front surface) of the substrate W, and are both provided to surround the substrate W. The second cup C2 has a larger diameter than the first cup C1 and is provided to surround the first cup C1. The upper wall surfaces that form the openings of the first cup C1 and the second cup C2 are bent so as to incline radially inward. The tip of this bent portion (hereinafter also referred to as the bent portion) is provided close to the holder 11 that holds the substrate W. As described below, the first cup C1 and the second cup C2 are provided with a first pipe D1 and a second pipe D2 to drain the processing liquid flowing along their respective inner wall surfaces, but the processing liquid received on the inner wall surface of the second cup C2 is blocked by the upper surface of the bent portion of the first cup C1 so as not to accidentally flow into the first pipe D1 (see Figure 2).

[0022] The inner wall surface of the first cup C1 is hydrophilic, for example, with numerous fine grooves engraved on it. The inner wall surface of the second cup C2 is hydrophobic, for example, with a PFA coating or made of PTFE. In this way, the first cup C1 and the second cup C2 have different inner wall properties.

[0023] The first cup C1 includes a moving mechanism M1. The moving mechanism M1 is controlled by the control unit 8 to move the first cup C1 up and down. The second cup C2 includes a moving mechanism M2. The moving mechanism M2 is controlled by the control unit 8 to move the second cup C2 up and down. As shown in FIG. 1, when the first cup C1 is in an upwardly moved state, the processing liquid splashed from the substrate W is received by the inner wall surface of the first cup C1. On the other hand, as shown in FIG. 2, when the second cup C2 is in an upwardly moved state and the first cup C1 is in a downwardly moved state, the inner wall surface of the second cup C2 is exposed to the processing liquid splashed from the substrate W. As a result, the processing liquid splashed from the substrate W is received by the inner wall surface of the second cup C2.

[0024] The findings of the present inventors regarding the relationship between the viscosity of the treatment liquid and the properties of the inner wall surface of the cup C will be described below.

[0025] When a high-viscosity processing liquid is received, the processing liquid is more likely to remain on the inner wall surface of cup C than when a low-viscosity processing liquid is received. Therefore, a high-viscosity processing liquid is more likely to remain in a mounded state (a state in which the contact angle of the droplets is large) on the inner wall surface of cup C than a low-viscosity processing liquid. When processing liquid newly scattered from substrate W collides with this mounded processing liquid, the impact causes the processing liquid to explode and break up into fine particles, turning into a mist. The mist-like processing liquid bounces back toward substrate W due to the impact of the collision and adheres to the processed surface of substrate W, which can cause production defects.

[0026] Highly viscous processing liquid is difficult to be popped due to its high viscosity. However, if the droplets remain in a raised state on the inner wall surface of the cup C as described above, they collide with the processing liquid newly scattered from the substrate W, lose their shape, and are popped into mist. At this time, if the inner wall surface of the cup C is hydrophilic, the processing liquid received on the inner wall surface stays spreading on the inner wall surface of the cup C. That is, the processing liquid received on the inner wall surface is more likely to have a flat shape (a state in which the contact angle of the droplets is small) than when the inner wall surface of the cup C is hydrophobic. The processing liquid attached in such a flat shape is less likely to lose its shape even when colliding with the processing liquid newly scattered from the substrate W, so there is little risk of it popping into mist. That is, the processing liquid becomes mist due to the impact of the collision, and there is little risk of it bouncing back to the substrate W side. Therefore, it is preferable to receive the highly viscous processing liquid in the hydrophilic first cup C1.

[0027] On the other hand, even if the processing liquid has a low viscosity, when the processing liquid is received by the cup C whose inner wall surface is hydrophilic, the processing liquid is likely to become flat (the contact angle of the droplets is small) on the inner wall surface of the cup C. However, the processing liquid with a low viscosity is more likely to be popped than the processing liquid with a high viscosity due to the viscosity of the processing liquid itself. That is, when the processing liquid newly scattered from the substrate W collides with the processing liquid with a low viscosity, the processing liquid is likely to be popped and become mist-like due to the impact even if the processing liquid remains on the inner wall surface of the cup C. At this time, if the inner wall surface of the cup C is hydrophobic, the low-viscosity processing liquid has a weak adhesion force to the inner wall surface of the cup C due to its low viscosity, and becomes droplet-like (the contact angle of the droplets is large). That is, even a small amount of the processing liquid is unlikely to remain on the inner wall surface of the cup C, and is likely to flow down along the inner wall surface of the cup C. Therefore, the risk of the processing liquid newly scattered from the substrate W colliding with the processing liquid remaining on the inner wall surface of the cup C is suppressed, and the processing liquid is unlikely to become mist-like. Since the processing liquid is unlikely to become mist, the processing liquid is prevented from bouncing back towards the substrate W and adhering to the substrate W. Therefore, it is preferable that the low-viscosity processing liquid be received in the hydrophobic second cup C2.

[0028] As described above, the first cup C1 with a hydrophilic inner wall surface and the second cup C2 with a hydrophobic inner wall surface are appropriately used to receive the processing liquid according to the viscosity of the processing liquid, thereby preventing the processing liquid from becoming misty. Since the processing liquid is less likely to become misty, the processing liquid is prevented from bouncing back toward the substrate W and adhering to the substrate W. It should be noted that which processing liquid is suitable for receiving in the cup C with which inner wall surface can be determined in advance by measuring the amount of mist generation through experiments or the like. In this embodiment, the first cup C1 with a hydrophilic inner wall surface is used to receive the processing liquid for BHF, and the second cup C2 with a hydrophobic inner wall surface is used to receive the processing liquid for DIW, ozone water, and HF.

[0029] The piping D includes a first piping D1 provided on the bottom surface of the first cup C1 and a second piping D2 provided on the bottom surface of the second cup C2 outside the first cup C1. The first piping D1 discharges (drains) the processing liquid that has flowed down the inner wall surface of the first cup C1. The second piping D2 discharges (drains) the processing liquid that has flowed down the inner wall surface of the second cup C2. Specifically, the first piping D1 and the second piping D2 are each connected to a gas-liquid separator (not shown). The processing liquid that has flowed down the inner wall surface of the cup C is sent by the gas-liquid separator to a processing liquid recovery tank or a waste liquid discharge facility of the factory and discharged. In addition, the gas-liquid separator can change the destination of the liquid depending on the type of processing liquid, and thus the processing liquid can be discharged according to the type. The exhaust gas is sent by the gas-liquid separator to an exhaust facility of the factory and discharged.

[0030] The detection unit 15 is a sensor such as a photoelectric sensor. In the following, the detection unit 15 will be described as a reflective photoelectric sensor in which a light-emitting unit and a light-receiving unit are integrated. The detection unit 15 is provided above the cup C at a position that does not interfere with the lifting and lowering operation of the cup C. The detection unit 15 is provided so that its optical axis is parallel to the surface of the substrate W. The height of the optical axis of the detection unit 15 is, for example, slightly higher than the upper end of the cup C that has moved upward. The detection unit 15 detects droplets (hereinafter also referred to as mist) of the processing liquid that are scattered from the substrate W, received on the inner wall surface of the cup C, and bounced back from the inner wall surface of the cup C toward the substrate W. In this way, the detection unit 15 detects droplets (mist) of the processing liquid that bounce back to a height that reaches the optical axis. When the detector 15 detects splashes of a predetermined amount or more of the processing liquid, under the control of the controller 8, the driver 12 reduces the rotation speed of the substrate W, and the supply unit 13 reduces the supply amount of the processing liquid.

[0031] The control unit 8 is configured, for example, by a dedicated electronic circuit or a computer operating on a predetermined program, and controls each component of the substrate processing apparatus 1. As shown in FIG. 3 , the control unit 8 includes a holding control unit 81, a drive control unit 82, a supply control unit 83, a movement control unit 84, a storage unit 85, a setting unit 86, and an input / output control unit 87.

[0032] The holding control unit 81 controls the holding unit 11 to hold the substrate W. The drive control unit 82 controls the drive unit 12 to rotate or stop the substrate W. The drive control unit 82 also controls the drive unit 12 to change the rotation speed of the substrate W. For example, when the detection unit 15 detects splashes of a predetermined amount or more of the processing liquid, the drive control unit 82 reduces the rotation speed of the substrate W.

[0033] The supply control unit 83 controls the supply unit 13 to move the nozzle and further to supply or stop the treatment liquid. The supply control unit 83 also controls the supply unit 13 to change the amount of treatment liquid supplied. For example, when the detection unit 15 detects a predetermined amount or more of splashes of the treatment liquid, the supply amount of the treatment liquid is reduced.

[0034] The movement control unit 84 controls the first cup C1 and the second cup C2 included in the discharge unit 14. Specifically, the movement control unit 84 controls the movement mechanism M1 included in the first cup C1 and the movement mechanism M2 included in the second cup C2 to move the first cup C1 and the second cup. For example, by raising and lowering the first cup C1 in a state in which the first cup C1 and the second cup C2 are raised, it is possible to select whether the processing liquid scattered from the substrate W is received on the inner wall surface of the first cup C1 or the inner wall surface of the second cup C2. That is, the movement control unit 84 moves the first cup C1 and the second cup C2 to receive the processing liquid scattered from the substrate W on either the inner wall surface of the first cup C1 or the inner wall surface of the second cup C2. This makes it possible to select a cup C that is less likely to generate mist depending on the type of processing liquid. In addition, the processing liquid can be discharged according to its type by a pipe D provided at the bottom of the selected cup C.

[0035] The storage unit 85 is a recording medium such as an HDD or SSD. Data and programs necessary for the operation of the system are stored in advance in the storage unit 85, and the storage unit 85 also stores data necessary for the operation of the system. The setting unit 86 is a processing unit that sets information in the storage unit 85 according to an input. The input / output control unit 87 is an interface that controls signal conversion and input / output between each configuration to be controlled.

[0036] An input device 91 and an output device 92 are connected to the control unit 8. The input device 91 is input means such as a switch, a touch panel, a keyboard, a mouse, etc., which allows an operator to operate the substrate processing apparatus 1 via the control unit 8. The operator can input various information to be set in the storage unit 85 using the input device 91. The output device 92 is output means such as a display, a lamp, a meter, etc., which makes information for checking the state of the apparatus visible to the operator. For example, the output device 92 can display an input screen for information from the input device 91.

[0037] (action) The operation of the substrate processing apparatus 1 will be described with reference to the flow chart of FIG. 4. As a premise, the substrate W is held by the chuck pins P provided on the table T of the holder 11. The first cup C1 and the second cup C2 are moved upward by the moving mechanisms M1 and M2 as shown in FIG. 1. That is, the processing liquid splashed from the substrate W is received on the inner wall surface of the first cup C1. This premise is realized by first lowering the first cup C1 and the second cup C2, transporting the substrate W to the substrate processing apparatus 1, and then having the holder 11 hold the substrate W and raising the first cup C1 and the second cup C2.

[0038] First, under the control of the drive control unit 82, the drive unit 12 rotates the substrate W at a predetermined rotation speed (step S01). Next, under the control of the supply control unit 83, the supply unit 13 supplies a predetermined amount of BHF to the processing surface of the substrate W, and the BHF scattered from the substrate W is received in the hydrophilic first cup C1 (step S02). The BHF received in the first cup C1, whose inner wall surface is hydrophilic, is drained from the first pipe D1. At this time, the highly viscous BHF remains so as to spread on the inner wall surface of the first cup C1, and tends to have a flat shape (a state in which the contact angle of the droplets is small), so that the generation of mist caused by collision with newly scattered BHF and repelling and the rebounding to the substrate W side are suppressed. This makes it possible to suppress the attachment of the mist to the processing surface of the substrate W.

[0039] When the etching of the substrate W with BHF is performed for a predetermined time, the supply unit 13 stops the supply of BHF under the control of the supply control unit 83 (step S03). Then, the discharge unit 14 moves the first cup C1 downward as shown in FIG. 2, and exposes the second cup C2 that has been moved upward in advance (step S04). When the second cup C2 is exposed, the supply unit 13 switches the processing liquid to be supplied from BHF to DIW under the control of the supply control unit 83 in order to remove the BHF from the substrate W, supplies a predetermined amount of DIW to the surface of the substrate W, and receives it in the second cup C2 whose inner wall surface is hydrophobic (step S05). The DIW received in the second cup C2 flows downward along the inner wall surface of the second cup C2 and is discharged from the second pipe D2. At this time, the low-viscosity DIW has a weak adhesion to the inner wall surface of the hydrophobic second cup C2 due to its low viscosity, and forms droplets (a state in which the contact angle of the droplets is large). In other words, the DIW flows continuously without remaining on the inner wall surface of the second cup C2, reducing the risk of collision with newly scattered DIW. This reduces the generation of mist and its rebounding toward the substrate W, and makes it possible to prevent the mist from adhering to the processing surface of the substrate W.

[0040] When the substrate W is rinsed with DIW for a predetermined time, the supply unit 13 stops supplying DIW under the control of the supply control unit 83. The movement control unit 84 lowers the first cup C1 and maintains the second cup C2 in an elevated state. Next, under the control of the supply control unit 83, the supply unit 13 switches the processing liquid to be supplied from DIW to ozone water in order to form an oxide film on the processing surface of the substrate W, supplies a predetermined amount of ozone water to the surface of the substrate W, and causes the second cup C2, whose inner wall surface is hydrophobic, to receive the ozone water (step S06). The ozone water received in the second cup C2 flows downward along the inner wall surface of the second cup C2 and is drained from the second pipe D2. At this time, the low-viscosity ozone water has a weak adhesion to the inner wall surface of the hydrophobic second cup C2 due to its low viscosity, and forms droplets (a state in which the contact angle of the droplets is large). In other words, since the ozone water flows continuously without remaining on the inner wall surface of the second cup C2, the risk of collision with newly scattered ozone water is reduced, thereby suppressing the generation of mist and its rebounding onto the substrate W, and preventing the mist from adhering to the processed surface of the substrate W.

[0041] When the oxide film is formed on the substrate W by the ozone water for a predetermined time, the supply unit 13 stops supplying the ozone water under the control of the supply control unit 83. The movement control unit 84 lowers the first cup C1 and maintains the second cup C2 in the raised state. Next, the supply unit 13 switches the processing liquid to be supplied from the ozone water to HF under the control of the supply control unit 83 in order to remove the oxide film from the substrate W, supplies a predetermined amount of HF to the processing surface of the substrate W, and causes the second cup C2, whose inner wall surface is hydrophobic, to receive the HF (step S07). The HF received in the second cup C2 flows downward along the inner wall surface of the second cup C2 and is drained from the second pipe D2. At this time, the low-viscosity HF has a weak adhesion to the inner wall surface of the hydrophobic second cup C2 due to its low viscosity, and forms droplets (a state in which the contact angle of the droplets is large). In other words, since the HF flows continuously without remaining on the inner wall surface of the second cup C2, the risk of collision with newly scattered HF is reduced, thereby suppressing the generation of mist and its rebounding onto the substrate W, and preventing the mist from adhering to the processed surface of the substrate W.

[0042] When the etching of the substrate W by HF is performed for a predetermined time, the supply unit 13 stops supplying HF under the control of the supply control unit 83. The movement control unit 84 lowers the first cup C1 and maintains the second cup C2 in an elevated state. Next, under the control of the supply control unit 83, the supply unit 13 switches the processing liquid to be supplied from HF to ozone water in order to form an oxide film on the substrate W, supplies a predetermined amount of ozone water to the processing surface of the substrate W, and receives it in the second cup C2 whose inner wall surface is hydrophobic (step S08). The ozone water received in the second cup C2 flows downward along the inner wall surface of the second cup C2 and is drained from the second pipe D2. At this time, the low-viscosity ozone water has a weak adhesion to the inner wall surface of the hydrophobic second cup C2 due to its low viscosity, and forms droplets (a state in which the contact angle of the droplets is large). In other words, since the ozone water flows continuously without remaining on the inner wall surface of the second cup C2, the risk of collision with newly scattered ozone water is reduced, thereby suppressing the generation of mist and its rebounding onto the substrate W, and preventing the mist from adhering to the processed surface of the substrate W.

[0043] When the oxide film is formed on the substrate W by the ozone water for a predetermined time, the supply unit 13 stops supplying the ozone water under the control of the supply control unit 83. The movement control unit 84 lowers the first cup C1 and maintains the second cup C2 in an elevated state. Next, under the control of the supply control unit 83, the supply unit 13 switches the processing liquid to be supplied from the ozone water to the DIW in order to remove HF from the substrate W, supplies a predetermined amount of DIW to the processing surface of the substrate W, and causes the second cup C2, whose inner wall surface is hydrophobic, to receive the DIW (step S09). The DIW received in the second cup C2 flows downward along the inner wall surface of the second cup C2 and is drained from the second pipe D2. At this time, the low-viscosity DIW has a weak adhesion to the inner wall surface of the hydrophobic second cup C2 due to its low viscosity, and forms droplets (a state in which the contact angle of the droplets is large). In other words, since the DIW flows continuously without remaining on the inner wall surface of the second cup C2, the risk of collision with newly scattered DIW is reduced, thereby suppressing the generation of mist and its rebounding onto the substrate W, and preventing the mist from adhering to the processed surface of the substrate W.

[0044] When the substrate W is rinsed with DIW for a predetermined time, the supply unit 13 stops supplying DIW under the control of the supply control unit 83 (step S10). Finally, the drive unit 12 increases the rotation speed of the substrate W under the control of the drive control unit 82 (step S11). As a result, the DIW is shaken off from the substrate W, and the substrate W is dried. The shaken off DIW is received on the inner wall surface of the second cup C2 and drained from the second pipe D2. At this time, the low-viscosity DIW has a weak adhesion force to the inner wall surface of the hydrophobic second cup C2 due to its low viscosity, and becomes a droplet shape (a state in which the contact angle of the droplet is large). In other words, the DIW flows one after another without staying on the inner wall surface of the second cup C2, so that the risk of collision with newly scattered DIW is suppressed, and thus the generation of mist and the rebounding to the substrate W side are suppressed, and the adhesion of the mist to the processed surface of the substrate W can be suppressed.

[0045] Furthermore, in the processing of the substrate W in the above-mentioned steps S01 to 11, if the detection unit 15 detects splashes of the processing liquid in a predetermined amount or more, the drive unit 12 may reduce the rotation speed of the substrate W under the control of the drive control unit 82, and the supply unit 13 may reduce the supply amount of the processing liquid under the control of the supply control unit 83. This reduces the momentum of the processing liquid received on the inner wall surface of the cup C and also reduces the amount of the processing liquid, so that even if the mist cannot be sufficiently suppressed by selecting a cup C having an inner wall surface suitable for the viscosity of the processing liquid, it is possible to effectively suppress the generation of mist due to collision of the processing liquid and the rebounding of the processing liquid toward the substrate W. This makes it possible to effectively suppress the attachment of the mist to the processing surface of the substrate W.

[0046] The rotation speed of the substrate W may be reduced uniformly to a predetermined rotation speed, or may be reduced gradually until the detection unit 15 no longer detects droplets of the processing liquid of a predetermined amount or more. In this case, the rotation speed of the substrate W may be maintained at the point in time when the detection unit 15 no longer detects droplets of the processing liquid of a predetermined amount or more.

[0047] The supply amount of the treatment liquid may be reduced uniformly to a predetermined supply amount, or may be reduced gradually until the detection unit 15 does not detect droplets of the treatment liquid of a predetermined amount or more. In this case, the supply amount of the treatment liquid may be maintained at the point in time when the detection unit 15 does not detect droplets of the treatment liquid of a predetermined amount or more.

[0048] Furthermore, the rotation speed of the substrate W and the supply amount of the processing liquid maintained at the time when the detection unit 15 no longer detects splashes of the processing liquid of a predetermined amount or more may be stored in the memory unit 85 and used for the next or subsequent processing of the substrate W. Note that, if the detection unit 15 again detects splashes of the processing liquid of a predetermined amount or more in the next or subsequent processing of the substrate W, the rotation speed of the substrate W and the supply amount of the processing liquid may be adjusted again, and the adjusted rotation speed of the substrate W and the supply amount of the processing liquid may be used again.

[0049] (effect) (1) The substrate processing apparatus 1 of this embodiment includes a holder 11 for holding a substrate W, a drive unit 12 provided in the holder 11 and for rotating the substrate W together with the holder 11, a supply unit 13 for supplying a processing liquid to a surface of the substrate W to be processed in order to process the substrate W, a first cup C1 provided to surround the substrate W, a second cup C2 provided to surround the first cup C1 and having an inner wall surface with properties different from those of the first cup C1, and a movement control unit 84 for moving the first cup C1 and the second cup C2 to cause the processing liquid splashed from the substrate W to be received on either the inner wall surface of the first cup C1 or the inner wall surface of the second cup C2. This makes it possible to select a cup C having an inner wall surface suitable for receiving the processing liquid depending on the viscosity of the processing liquid. For example, for a highly viscous processing liquid that is received and retained on the inner wall surface of the cup C, a cup C that can reduce the contact angle of droplets on the inner wall surface can be selected, and for a low-viscosity processing liquid that is likely to burst and become mist when received on the inner wall surface of the cup C, a cup C that is less likely to retain on the inner wall surface can be selected. This reduces the risk of mist being generated when the processing liquid remaining on the inner wall surface collides with newly scattered processing liquid, or the risk of the processing liquid not remaining on the inner wall surface colliding with newly scattered processing liquid, thereby suppressing the generation of mist. In either case, suppressing the generation of mist can prevent the mist from adhering to the surface to be processed of the substrate W.

[0050] (2) In this embodiment, the inner wall surface of the first cup C1 is hydrophilic, and the inner wall surface of the second cup C2 is hydrophobic. As a result, when the processing liquid is highly viscous, such as BHF, the contact angle of the processing liquid on the inner wall surface is reduced by receiving the processing liquid on the hydrophilic inner wall surface of the first cup C1, and the possibility of collision with newly scattered processing liquid and generation of mist can be suppressed. When the processing liquid is low viscous, such as DIW, ozone water, or HF, the contact angle of the processing liquid on the inner wall surface is increased by receiving the processing liquid on the hydrophobic inner wall surface of the second cup C2, and the possibility of collision with newly scattered processing liquid without retaining the processing liquid can be suppressed, and thus the generation of mist can be suppressed. In either case, the generation of mist can be suppressed, and thus the attachment of the mist to the processing surface of the substrate W can be suppressed.

[0051] (3) The substrate processing apparatus 1 of this embodiment further includes a detection unit 15 that detects splashes of the processing liquid received on either the inner wall surface of the first cup C1 or the inner wall surface of the second cup C2 and bounces back to the substrate W. When the detection unit 15 detects splashes of the processing liquid of a predetermined amount or more, the drive unit 12 reduces the rotation speed of the substrate W, and the supply unit 13 reduces the amount of processing liquid supplied to the substrate W. This reduces the momentum of the processing liquid received on the inner wall surface of the cup C and reduces the amount of processing liquid. Therefore, even if the mist cannot be sufficiently suppressed by selecting a cup C having an inner wall surface suitable for the viscosity of the processing liquid, it is possible to effectively suppress the generation of mist due to collision of the processing liquid and the rebounding to the substrate W. This effectively suppresses the attachment of mist to the processing surface of the substrate W.

[0052] [Variations] (1) In the above embodiment, the first cup C1 is hydrophilic and the second cup C2 provided outside the first cup C1 is hydrophobic, but this is not limited thereto. The first cup C1 may be hydrophobic and the second cup C2 provided outside the first cup C1 may be hydrophilic. In this case, as in the above embodiment, if a process using BHF, which is a high-viscosity processing liquid, is performed first, and then a process using DIW, ozone water, and HF, which are low-viscosity processing liquids, is performed, the first cup C1 is moved downward at the stage of the process using BHF, and the second cup C2 is exposed to the processing liquid splashed from the substrate W. As a result, the high-viscosity BHF is received by the hydrophilic second cup C2 provided outside, so that the contact angle of the processing liquid on the inner wall surface is reduced, and the risk of collision with the newly splashed processing liquid and generation of mist can be suppressed. On the other hand, in the stage of processing with DIW, ozone water, and HF, the first cup C1 is moved upward and made to face the processing liquid splashed from the substrate W. As a result, the low-viscosity DIW, ozone water, and HF are received by the hydrophobic first cup C1 and flow one after another without remaining on the inner wall surface of the first cup C1, so that the processing liquid is prevented from remaining on the inner wall surface and colliding with newly splashed processing liquid, thereby suppressing the generation of mist. In either case, suppressing the generation of mist makes it possible to suppress the mist from adhering to the processing surface of the substrate W.

[0053] (2) In the above embodiment, when the detection unit 15 detects splashes of a predetermined amount or more of processing liquid, the drive unit 12 reduces the rotation speed of the substrate W under the control of the drive control unit 82, and the supply unit 13 reduces the amount of processing liquid supplied under the control of the supply control unit 83. However, this is not limited to this. For example, the drive unit 12 may reduce the rotation speed of the substrate W, but the supply unit 13 may not reduce the amount of processing liquid supplied. Also, the supply unit 13 may reduce the amount of processing liquid supplied, but the drive unit 12 may not reduce the rotation speed of the substrate W. Note that the detection unit 15 may be omitted, and the rotation speed of the substrate W or the amount of processing liquid supplied may not be controlled in response to the detection by the detection unit 15.

[0054] (3) In the above embodiment, the detection unit 15 is a reflective photoelectric sensor in which the light-projecting unit and the light-receiving unit are integrated, but this is not limited to this. For example, it may be a transmissive photoelectric sensor in which the light-projecting unit and the light-receiving unit are separate. Furthermore, the detection unit 15 is not limited to a photoelectric sensor, and may be an infrared (IR) camera, a CCD camera, a CMOS camera, or the like.

[0055] (4) The processing liquid in the above embodiment is BHF, DIW, ozone water, and HF, but is not limited thereto. For example, any processing liquid suitable for processing the substrate W, such as sulfuric acid and phosphoric acid, may be used. The order in which the processing liquids are used in the above embodiment is merely an example, and the processing liquids may be used in any order. For example, the processing liquid may be used in the order of a low-viscosity processing liquid, a high-viscosity processing liquid, and a low-viscosity processing liquid. In this case, the processing liquid splashed from the substrate W may be received by facing the inner wall surface of the hydrophobic second cup C2, the inner wall surface of the hydrophilic first cup C1, and the inner wall surface of the hydrophobic second cup C2, respectively.

[0056] [Other embodiments] Although the embodiment of the present invention and the modified examples of each part have been described above, these embodiments and the modified examples of each part are presented as examples and are not intended to limit the scope of the invention. These novel embodiments described above can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims. [Explanation of symbols]

[0057] 1. Substrate Processing Equipment 11 Holding part 12 Drive unit 13 Supply section 14 Discharge section 15 Detection section 8. Control Unit 81 Retention control section 82 Drive control unit 83 Supply control section 84 Movement control section 85 Memory section 86 Setting section 87 Input / Output Control Unit 91 Input Devices 92 Output Device C Cup C1 First Cup C2 Second Cup D Piping D1 First pipe D2 Second piping M1, M2 movement mechanism P Chuck pin T Table W substrate

Claims

1. A holder for holding the substrate; a drive unit provided on the holder and configured to rotate the substrate together with the holder; a supply unit that supplies a processing liquid to a processing surface of the substrate in order to process the substrate; a first cup provided to surround the substrate, the first cup having an inner wall surface that is either hydrophilic or hydrophobic; a second cup provided to surround the first cup, the second cup having an inner wall surface that is either hydrophilic or hydrophobic; a movement control unit that moves the first cup and the second cup and causes the processing liquid splashed from the substrate to be received on one of an inner wall surface of the first cup and an inner wall surface of the second cup; A substrate processing apparatus comprising:

2. The movement control unit is When the processing liquid has a high viscosity, the processing liquid splashed from the substrate is received on an inner wall surface of the first cup or the second cup, the inner wall surface of which is hydrophilic; when the processing liquid has a low viscosity, moving the first cup and the second cup so that the processing liquid splashed from the substrate is received on an inner wall surface of the first cup or the second cup, the inner wall surface of whichever of the first cup and the second cup is hydrophobic; The substrate processing apparatus according to claim 1 .

3. a detection unit that detects splashes of the processing liquid received on one of an inner wall surface of the first cup and an inner wall surface of the second cup and rebounding toward the substrate, When the detection unit detects splashes of the processing liquid in an amount equal to or greater than a predetermined amount, the drive unit reduces the rotation speed of the substrate. The substrate processing apparatus according to claim 1 .

4. a detection unit that detects splashes of the processing liquid received on one of an inner wall surface of the first cup and an inner wall surface of the second cup and rebounding toward the substrate, When the detection unit detects a predetermined amount or more of splashes of the processing liquid, the supply unit reduces the amount of the processing liquid supplied to the substrate. The substrate processing apparatus according to claim 1 .

5. holding a substrate; rotating the held substrate; supplying a processing liquid to a processing surface of the substrate to process the substrate; a step of moving a first cup arranged to surround the substrate and having an inner wall surface which is either hydrophilic or hydrophobic, and a second cup arranged to surround the first cup and having an inner wall surface which is either hydrophilic or hydrophobic, and causing the processing liquid splashed from the substrate to be received on one of the inner wall surface of the first cup or the inner wall surface of the second cup; A substrate processing method comprising:

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