JP2016134390A - Substrate processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate processing apparatus capable of executing supply and supply stop of process liquid, and adjustment of the flow rate of process liquid by means of one valve, while reducing particles.SOLUTION: A first valve 14 includes a body 25 in which a flow path 30 is formed, a valve element 31 for opening and closing the flow path 30, and an electric motor 23 generating a power for moving the valve element 31 in an axial direction X1. The valve element 31 includes a pyramid 33 inserted into an opening 27, and an annular portion 34 surrounding the pyramid 33 while spaced apart therefrom, and facing a valve seat 28. The pyramid 33 includes a pyramidal outer peripheral surface, that is in noncontact with the body 25 at any position from a close position to an open position. The annular portion 34 includes an annular tip being pressed against the valve seat 28 perpendicularly thereto at the close position, and separating from the valve seat 28 at positions other than the close position.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a substrate processing apparatus for processing a substrate. Examples of substrates to be processed include semiconductor wafers, liquid crystal display substrates, plasma display substrates, FED (Field Emission Display) substrates, optical disk substrates, magnetic disk substrates, magneto-optical disk substrates, and photomasks. Substrate, ceramic substrate, solar cell substrate and the like.

  Patent Document 1 discloses a single-wafer type substrate processing apparatus that processes substrates such as semiconductor wafers one by one. The substrate processing apparatus includes a processing liquid nozzle that discharges a processing liquid supplied to a substrate, and an on-off valve that controls supply and stop of supply of the processing liquid to the processing liquid nozzle (first chemical liquid valve, second chemical liquid valve, rinse) A liquid valve) and a flow rate adjusting valve for changing the flow rate of the processing liquid supplied to the processing liquid nozzle. The flow rate adjusting valve is an electric valve including a motor that moves a needle that changes the opening degree of the flow rate adjusting valve.

JP 2010-123709 A

In the substrate processing apparatus, an opening / closing valve and a flow rate adjusting valve are provided. Many moving parts not only increase costs and require more space, but also increase the likelihood of particles that contaminate the substrate.
In the substrate processing apparatus, it is conceivable to omit the open / close valve and cause the flow rate adjusting valve to supply and stop the processing liquid and adjust the flow rate. However, in this case, when the supply of the processing liquid to the processing liquid nozzle is stopped, the conical valve body (needle) rubs against the conical valve seat, so that particles are generated due to wear of the valve body and the valve seat. End up.

  Accordingly, one of the objects of the present invention is to perform supply and stop of the treatment liquid to the treatment liquid nozzle and adjustment of the flow rate of the treatment liquid supplied to the treatment liquid nozzle with one valve while reducing particles. It is providing the substrate processing apparatus which can be performed.

  The invention described in claim 1 for achieving the object includes a processing liquid nozzle for discharging a processing liquid supplied to a substrate, supply and stop of supply of the processing liquid to the processing liquid nozzle, and the processing liquid nozzle. An electric valve that adjusts the flow rate of the supplied processing liquid; and a control device that controls the electric valve. The electric valve has an inlet into which the processing liquid flows, and a process that has flowed into the inlet. An outlet for discharging liquid; an opening disposed between the inlet and the outlet; a flow path extending from the inlet to the outlet through the opening; and an annular valve surrounding the opening A main body provided with a seat, a closed position in contact with the valve seat and blocking the flow of the processing liquid from the inlet to the outlet, away from the valve seat, and through the opening, the flow And an open position for flowing the processing liquid from the inlet to the outlet. A valve body movable with respect to the main body, and the valve body is moved between the closed position and the open position, and an arbitrary position from the closed position to the open position according to a command from the control device An electric actuator for positioning the valve body at a position, and the valve body surrounds the cone part with a gap therebetween and is opposed to the valve seat. An annular portion, and the cone portion includes a cone-shaped outer peripheral surface that is not in contact with the main body at any position from the closed position to the open position, and the annular portion is the closed portion. The substrate processing apparatus includes an annular tip portion that is pressed perpendicularly to the valve seat at a position and separates from the valve seat at a position other than the closed position.

According to this invention, the cone part inserted in opening and the annular part which opposes a valve seat are provided in the valve body. The electric actuator moves the valve body between the closed position and the open position in accordance with a command from the control device. When the electric actuator moves the valve body, the cone portion and the annular portion move.
Due to the movement of the cone portion, the flow path area of the opening (the area of the portion not occupied by the cone portion) continuously changes. The flow rate of the processing liquid supplied to the processing liquid nozzle is automatically adjusted by an electric actuator. When the electric actuator positions the valve body in the closed position, the annular portion contacts the valve seat, and when the electric actuator positions the valve body in a position other than the closed position, the annular portion moves away from the valve seat. Supply and stop of the processing liquid to the processing liquid nozzle are automatically switched by an electric actuator. Therefore, the supply and stop of the supply of the treatment liquid to the treatment liquid nozzle and the adjustment of the flow rate of the treatment liquid supplied to the treatment liquid nozzle can be performed with one valve (electric valve).

  The outer peripheral surface of the cone portion is not in contact with the main body at any position from the closed position to the open position. Therefore, the movement of the valve body does not rub the cone portion against the main body and generate particles. Further, the annular tip portion of the annular portion is pressed perpendicularly to the valve seat in the closed position. Therefore, particles are less likely to be generated than when a conical valve body is pressed against a conical or cylindrical valve seat. Therefore, particles generated in the flow path can be reduced, and the cleanliness of the processing liquid supplied to the substrate can be increased.

The invention according to claim 2 is the substrate processing apparatus according to claim 1, wherein the valve seat and the annular tip are both flat.
According to the invention, the flat annular tip is pressed vertically against the flat valve seat. As a result, the valve seat and the annular tip end come into surface contact. Therefore, compared with the case where the valve body and the valve seat are in line contact, the flow of the treatment liquid can be blocked more reliably. Furthermore, since the planes are pressed vertically, particles are less likely to be generated than when a conical valve body is pressed against a conical or cylindrical valve seat. Thereby, the particle | grains which generate | occur | produce in a flow path can be reduced.

The invention according to claim 3 is the substrate processing apparatus according to claim 1, wherein an inner diameter of the annular tip portion is larger than a diameter of the opening.
If the contact area between the valve body and the valve seat is too small, sufficient sealing performance cannot be secured. On the other hand, if the contact area between the valve body and the valve seat is too large, a large pressure is required to close the valve. For this reason, the contact area between the valve body and the valve seat is preferably as small as possible within a range in which sufficient sealing performance can be secured. According to the present invention, since the inner diameter of the annular tip is larger than the diameter of the opening, the contact area between the valve seat and the annular tip can be reduced as compared with the case where the inner diameter of the annular tip is equal to or less than the diameter of the opening. Therefore, it is possible to reduce particles while more reliably blocking the flow of the treatment liquid.

  According to a fourth aspect of the present invention, the substrate processing apparatus further includes a flow meter that detects a flow rate of the processing liquid that passes through the electric valve, and the control device includes the valve body that is located in the closed position. The distance in the radial direction from the edge of the opening to the cone part (the direction perpendicular to the center line of the cone part) is the axial direction from the annular part to the valve seat (the direction along the center line of the cone part). When moving to the target position corresponding to the target value of the flow rate of the processing liquid passing through the motor-operated valve through the intermediate position equal to the distance, the position closer to the open position than the intermediate position. From the intermediate position to the intermediate position, the first constant speed control is performed to move the valve element at a constant moving speed, and the valve element is moved from the intermediate position to the target position based on the detection value of the flow meter. Feedback control is performed. A substrate processing apparatus of any one.

A typical example of feedback control is PID control that performs proportional operation, integral operation, and differential operation. The feedback control is not limited to PID control, and may be proportional control that performs proportional operation, or PI control that performs proportional and integral operations.
According to the present invention, when the valve body is arranged at a position other than the closed position, the processing liquid that has flowed into the inflow port has a gap between the annular portion and the valve seat, a cone portion, and an edge of the opening. Pass through the gap between. At a position closer to the closed position than the intermediate position, the flow area between the annular portion and the valve seat is larger than the flow area of the opening (the flow area defined by the gap between the cone portion and the opening). Therefore, the flow rate of the processing liquid passing through the electric valve is limited. On the other hand, at the position closer to the open position than the intermediate position, the flow area of the opening is smaller than the flow area between the annular portion and the valve seat. To do.

  The control device performs first constant speed control for moving the valve body at a constant moving speed from the closed position to the intermediate position. Then, the control device performs feedback control for moving the valve body from the intermediate position to the target position based on the detection value of the flow meter. That is, since the target position is in a range where the flow path area of the opening determines the flow rate of the processing liquid, the control device has a range in which the flow path area between the annular portion and the valve seat limits the flow rate of the processing liquid. Quickly move the valve body out. Therefore, compared with the case where feedback control is performed from the beginning, the time until the measured value of the flow rate is stabilized can be shortened.

  According to a fifth aspect of the present invention, the substrate processing apparatus further includes a flow meter that detects a flow rate of the processing liquid that passes through the electric valve, and the control device is provided between an edge of the opening and the cone portion. When moving the valve body located on the open position side from the intermediate position where the radial distance is equal to the axial distance from the annular portion to the valve seat, to the closed position via the intermediate position, From the position on the open position side to the intermediate position with respect to the intermediate position, second constant speed control is performed to move the valve body at a constant moving speed, and at least partly from the intermediate position to the closed position. 5. The substrate processing apparatus according to claim 1, wherein deceleration control is performed to move the valve body at a moving speed smaller than a moving speed of the valve body in the second constant speed control. .

  According to the present invention, the control device performs the second constant speed control that moves the valve body at a constant moving speed from the initial position (position closer to the open position than the intermediate position) to the intermediate position. Then, at least in part from the intermediate position to the closed position, the control device performs deceleration control for moving the valve body at a moving speed smaller than the moving speed of the valve body in the second constant speed control. Thus, since the moving speed immediately before the valve body contacts the valve seat is reduced, the impact when the valve body contacts the valve seat can be reduced, and particles generated by contact between the valve body and the valve seat can be further reduced. Can be reduced.

It is the schematic diagram which looked at the inside of the processing unit with which the substrate processing apparatus concerning one embodiment of the present invention was equipped horizontally. It is sectional drawing for demonstrating a 1st valve | bulb. It is an enlarged view of the valve body with which the 1st valve was equipped. It is a graph which shows the relationship between the position of a valve body, and the flow-path area of a 1st valve. It is sectional drawing of the 1st valve | bulb which shows the state in which the valve body is located in a closed position. It is sectional drawing of the 1st valve | bulb which shows the state in which the valve body is located in the intermediate position. It is sectional drawing of the 1st valve | bulb which shows the state in which the valve body is located in an open position. It is a graph which shows the time change of the position of a valve body when a control apparatus opens a 1st valve. It is a graph which shows the time change of the position of a valve body when a control device closes the 1st valve.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic view of the inside of a processing unit 2 provided in a substrate processing apparatus 1 according to an embodiment of the present invention viewed horizontally.
The substrate processing apparatus 1 is a single-wafer type apparatus that processes a disk-shaped substrate W such as a semiconductor wafer one by one. The substrate processing apparatus 1 includes a plurality of processing units 2 that process a substrate W with a processing liquid, a transfer robot (not shown) that transfers the substrate W to the processing unit 2, and a control device 3 that controls the substrate processing apparatus 1. including.

The processing unit 2 holds the substrate W horizontally, rotates the substrate around the vertical rotation axis A1 passing through the central portion of the substrate W, and the processing liquid toward the substrate W held by the spin chuck 4. And a processing liquid nozzle 11 for discharging.
The spin chuck 4 includes a disc-shaped spin base 6 held in a horizontal posture, a plurality of chuck pins 5 that hold the substrate W in a horizontal posture above the spin base 6, and a central portion of the spin base 6. A spin shaft 7 extending downward and a spin motor 8 for rotating the spin base 6 and the chuck pin 5 around the rotation axis A1 by rotating the spin shaft 7 are included. The spin chuck 4 is not limited to a clamping chuck in which a plurality of chuck pins 5 are brought into contact with the peripheral end surface of the substrate W, and the back surface (lower surface) of the substrate W, which is a non-device forming surface, is adsorbed to the upper surface of the spin base 6. Thus, a vacuum chuck that holds the substrate W horizontally may be used.

  The substrate processing apparatus 1 includes a processing liquid pipe 12 that guides the processing liquid to the processing liquid nozzle 11, a first pipe 13 that leads the first chemical liquid to the processing liquid pipe 12, and a second pipe that leads the second chemical liquid to the processing liquid pipe 12. 16 and a third pipe 19 that guides pure water (deionized water) to the treatment liquid pipe 12. The substrate processing apparatus 1 further includes a first valve 14 interposed in the first pipe 13, a first flow meter 15 that detects the flow rate of the liquid passing through the first valve 14, and a second pipe 16. The second valve 17, the second flow meter 18 for detecting the flow rate of the liquid passing through the second valve 17, the third valve 20 interposed in the third pipe 19, and the third valve 20. And a third flow meter 21 for detecting the flow rate of the liquid.

  The first valve 14, the second valve 17, and the third valve 20 are all electric valves. The control device 3 opens and closes the valves 14, 17 and 20. The control device 3 further changes the flow rate of the liquid passing through each valve 14, 17, 20 by controlling the opening degree of each valve 14, 17, 20. Detection values of the first flow meter 15, the second flow meter 18, and the third flow meter 21 are input to the control device 3. The control device 3 obtains a measured value of the flow rate based on the detected values of the flow meters 15, 16, and 21. The control device 3 changes the opening of each valve 14, 17, 20 based on the detection value of each flow meter 15, 16, 21, thereby changing the flow rate measurement value (measured flow rate value) to the flow rate target value ( (Or close to the target flow rate value).

  An example of the first chemical solution is ammonia water. An example of the second chemical solution is hydrogen peroxide solution. When each of the valves 14, 17, 20 is opened, ammonia water having a flow rate corresponding to the opening degree of the first valve 14, hydrogen peroxide water having a flow rate corresponding to the opening degree of the second valve 17, and the third valve 20. The pure water having a flow rate corresponding to the opening degree is supplied to the processing liquid pipe 12. Thereby, SC-1 which is a mixed liquid of ammonia water, hydrogen peroxide water, and water is generated in the processing liquid pipe 12 and discharged from the processing liquid nozzle 11. When the first valve 14 and the second valve 17 are closed and the third valve 20 is opened, pure water is supplied to the processing liquid pipe 12 and discharged from the processing liquid nozzle 11.

When processing the substrate W, the control device 3 rotates the substrate W by controlling the spin chuck 4. In this state, the control device 3 causes the processing liquid nozzle 11 to eject SC-1 toward the upper surface of the rotating substrate W. Thereby, SC-1 which is an example of a chemical solution is supplied to the entire upper surface of the substrate W (chemical solution supply step).
After stopping the discharge of SC-1 from the processing liquid nozzle 11, the control device 3 causes the processing liquid nozzle 11 to discharge pure water, which is an example of a rinsing liquid, toward the rotating substrate W. Thereby, pure water is supplied to the entire upper surface of the substrate W, and the SC-1 adhering to the substrate W is washed away (rinse solution supplying step).

The control device 3 stops the discharge of pure water from the processing liquid nozzle 11 and then rotates the substrate W on the spin chuck 4 at a high speed. Thereby, the pure water adhering to the substrate W is spun off around the substrate W by centrifugal force. Therefore, pure water is removed from the substrate W, and the substrate W is dried (drying process).
FIG. 2 is a cross-sectional view for explaining the first valve 14 which is an example of the electric valve. Below, the 1st valve | bulb 14 is demonstrated. Although description of the second valve 17 and the third valve 20 is omitted, each of the second valve 17 and the third valve 20 has a configuration equivalent to that of the first valve 14.

  As shown in FIG. 2, the first valve 14 includes a main body 25 in which a flow path 30 that guides the processing liquid is formed, and a valve body 31 that opens and closes the flow path 30. The first valve 14 further includes an electric motor 23 that generates power for moving the valve body 31 in the axial direction X1 (a direction along the center line of the cone portion 33), and the rotation of the electric motor 23 is a straight line of the valve body 31. A motion conversion mechanism 22 that converts the motion into motion and a rotation angle sensor 24 that detects the rotation angle of the electric motor 23 are included. The part (liquid contact part) in contact with the treatment liquid in the first valve 14 is made of a synthetic resin (for example, a fluororesin) having resistance to the chemical liquid. The inner surface 30c of the flow path 30 and the outer surface of the valve body 31 are included in the liquid contact portion.

  An electric motor 23 which is an example of an electric actuator is controlled by the control device 3. Although not shown, the motion conversion mechanism 22 includes, for example, a male screw extending in the axial direction X1 and a female screw surrounding the male screw. When the electric motor 23 rotates, the valve element 31 moves in the axial direction X1 by a moving amount corresponding to the rotation angle of the electric motor 23. The control device 3 controls the electric motor 23 on the basis of the detection value of the rotation angle sensor 24 so that the valve can be moved to an arbitrary position from the closed position (position shown in FIG. 5) to the open position (position shown in FIG. 7). The body 31 is positioned. The control device 3 further changes the moving speed of the valve body 31 to an arbitrary speed by controlling the rotational speed of the electric motor 23.

  As shown in FIG. 2, the main body 25 includes an inlet 26 through which the processing liquid filtered by the filter flows in, an outlet 29 through which the processing liquid flowing into the inlet 26 is discharged, an inlet 26 and an outlet 29. A circular opening 27 disposed between the flow path 26 and the flow path 30 extending from the inlet 26 to the outlet 29 via the opening 27, and an annular valve seat 28 concentrically surrounding the opening 27. The flow path 30 includes an upstream portion 30 a that extends downstream from the inlet 26 and a downstream portion 30 b that extends upstream from the outlet 29. The upstream portion 30 a and the downstream portion 30 b intersect within the main body 25. The opening 27 is formed in the inner surface 30 c of the flow path 30. The first pipe 13 includes an upstream pipe 13 a connected to the inlet 26 and a downstream pipe 13 b connected to the outlet 29.

  As shown in FIG. 2, the valve body 31 includes a disc portion 32, a cone portion 33, and an annular portion 34. The disc part 32, the cone part 33, and the annular part 34 are, for example, integral. The valve body 31 has a closed position (position shown in FIG. 5) in which the annular portion 34 contacts the valve seat 28 and blocks the flow of the processing liquid from the inlet 26 to the outlet 29, and the annular portion 34 has the valve seat 28. And an open position (position shown in FIG. 7) through which the processing liquid flows from the inlet 26 to the outlet 29 via the opening 27, and is movable with respect to the main body 25. The flow of the processing liquid from the inlet 26 to the outlet 29 is blocked by the contact between the annular portion 34 and the valve seat 28. The flow rate of the processing liquid flowing from the inlet 26 to the outlet 29 is continuously adjusted by the cone portion 33.

As shown in FIG. 2, the disc part 32 is disposed in a recess provided in the main body 25. An end surface 32 a of the disc portion 32 is disposed in the flow path 30. The annular portion 34 extends from the end surface 32 a of the disc portion 32 toward the valve seat 28. The cone portion 33 extends from the end surface 32 a of the disc portion 32 toward the opening 27.
As shown in FIG. 3, the cone portion 33 includes a conical outer peripheral surface 33 a whose outer diameter continuously decreases as the distance from the disc portion 32 increases. The outer peripheral surface 33a of the cone part 33 is tapered toward the downstream. The outer peripheral surface 33a of the cone part 33 is inclined at a constant inclination angle with respect to the axial direction X1. The tip of the cone portion 33 is further away from the disc portion 32 in the axial direction X1 than the annular portion 34. The tip of the cone portion 33 is disposed downstream of the valve seat 28. The inner surface of the downstream portion 30b of the flow path 30 has a cylindrical shape surrounding the cone portion 33 concentrically. The edge 27a of the opening 27 corresponds to the upstream end of the inner surface of the downstream portion 30b. The cone portion 33 is inserted into the opening 27.

  As shown in FIG. 3, the annular portion 34 includes an annular tip portion 34a that faces the valve seat 28 in the axial direction X1. The annular tip portion 34a is, for example, a flat surface arranged on a plane orthogonal to the axial direction X1. Similarly, the valve seat 28 is, for example, a flat surface arranged on a plane orthogonal to the axial direction X1. The annular tip 34a and the valve seat 28 face each other in parallel. The inner peripheral surface of the annular portion 34 concentrically surrounds the outer peripheral surface 33a of the cone portion 33 with an interval in the radial direction Y1 (direction orthogonal to the axial direction X1). The end surface 32 a of the disc portion 32, the outer peripheral surface 33 a of the cone portion 33, and the inner peripheral surface of the annular portion 34 form an annular groove 35 that surrounds the cone portion 33.

  As shown in FIG. 3, the inner diameter of the annular tip 34 a is larger than the diameter of the opening 27, for example. The maximum diameter of the cone part 33 (the outer diameter of the base of the cone part 33) is smaller than the diameter of the opening 27, for example. Therefore, the outer diameter D1 of the cone portion 33 at the same position as the annular tip portion 34a in the axial direction X1 is smaller than the diameter of the opening 27. The width of the annular tip portion 34a (the length in the radial direction Y1 from the inner edge of the annular tip portion 34a to the outer edge of the annular tip portion 34a) is, for example, the height of the annular portion 34 (from the end surface 32a of the disc portion 32 to the annular tip end). Smaller than the length in the axial direction X1 to the portion 34a. The difference between the inner diameter of the annular tip 34a and the diameter of the opening 27 (the distance in the radial direction Y1 from the edge 27a of the opening 27 to the inner end of the annular tip 34a) is, for example, the height of the annular part 34. Smaller than the width of the annular tip 34a.

  As shown in FIG. 2, when the valve body 31 is disposed at the closed position, the entire circumference of the annular tip portion 34a is pressed against the entire circumference of the valve seat 28, and the annular portion 34 is elastically deformed. Since there is a space between the annular portion 34 and the cone portion 33 and the annular portion 34 is separated from the cone portion 33, the elastic deformation of the annular portion 34 is not easily inhibited by the cone portion 33. The annular tip 34a is brought into close contact with the valve seat 28 by elastic deformation and is in surface contact with the valve seat 28. Thereby, the clearance gap between the valve body 31 and the valve seat 28 is sealed. On the other hand, when the valve body 31 is arranged at a position other than the closed position, the annular tip 34a is separated from the valve seat 28, and the processing liquid that has flowed into the inflow port 26 is in contact with the inner surface 30c of the flow path 30 and the valve body 31. Between the outer surface and the outlet 29.

  As shown in FIGS. 5 to 7, a part of the cone portion 33 is disposed in the opening 27 at any position from the closed position to the open position. The outer peripheral surface 33a of the cone portion 33 is not in contact with the main body 25 at any position from the closed position to the open position. When the valve body 31 moves to the open position side, the area where the cone portion 33 occupies the opening 27 continuously increases. When the valve body 31 moves to the closed position side, the area where the cone portion 33 occupies the opening 27 continuously decreases. Thereby, the flow path area of the opening 27 (the area of the portion not occupied by the cone portion 33) is changed, and the flow rate of the processing liquid passing through the first valve 14 is changed.

  As shown in FIG. 3, the distance in the axial direction X1 (axial distance Da) from the annular tip 34a to the valve seat 28 increases as the valve body 31 approaches the open position. Similarly, the distance in the radial direction Y1 (the radial distance Dr) from the edge 27a of the opening 27 to the outer peripheral surface 33a of the cone portion 33 increases as the valve body 31 approaches the open position. The rate of change of the axial distance Da is greater than the rate of change of the radial distance Dr.

A position where the radial distance Dr and the axial distance Da are equal is an intermediate position between the closed position and the open position. At the intermediate position, the channel area between the annular part 34 and the valve seat 28 (axial distance Da × circumferential length of the annular part 34) and the channel area of the opening 27 (the part not occupied by the cone part 33). ) Is almost the same.
When the valve body 31 is arranged at a position other than the closed position, the processing liquid that has flowed into the inflow port 26 has a gap between the annular portion 34 and the valve seat 28, and the cone portion 33 and the edge 27 a of the opening 27. And pass through the gap between. The flow rate of the processing liquid passing through the first valve 14 is limited by either the flow path area between the annular portion 34 and the valve seat 28 or the flow path area of the opening 27.

  As shown in FIG. 4, at the position closer to the closed position than the intermediate position, the flow path area between the annular portion 34 and the valve seat 28 is smaller than the flow path area of the opening 27. The flow rate of the processing liquid passing therethrough is limited. On the other hand, since the flow path area of the opening 27 is smaller than the flow path area between the annular portion 34 and the valve seat 28 at the position closer to the open position than the intermediate position, the process of passing through the first valve 14 is performed. Limit the flow rate of the liquid.

FIG. 8 shows a temporal change in the position of the valve body 31 when the control device 3 opens the first valve 14. FIG. 9 shows a temporal change in the position of the valve body 31 when the control device 3 closes the first valve 14.
In FIG. 8, the solid line is an example, the one-dot chain line is Comparative Example 1, and the two-dot chain line is Comparative Example 2. The target position in FIG. 8 is a position corresponding to the target value of the flow rate of the processing liquid passing through the first valve 14. That is, when the valve body 31 is disposed at the target position, the flow rate of the processing liquid that passes through the first valve 14 matches the target value of the flow rate. Hereinafter, a case where the target position is a position closer to the open position than the intermediate position will be described.

As shown in FIG. 8, the control device 3 performs the first constant speed control that moves the valve element 31 at a constant moving speed from the closed position to the intermediate position. And the control apparatus 3 performs PID control which moves the valve body 31 based on the detected value of the 1st flow meter 15 from an intermediate position to a target position.
In order to increase the quick response of the first valve 14, the control device 3 moves the valve element 31 at, for example, the maximum speed in the first constant speed control. Further, the PID constant is set, for example, so that overshoot does not occur. That is, the PID constant is set so that the position of the valve body 31 does not exceed the target position and the measured value of the flow rate does not exceed the target value of the flow rate.

  The one-dot chain line in FIG. 8 (Comparative Example 1) shows a temporal change in the position of the valve body 31 when the constant velocity control is performed until the measured value of the flow rate exceeds the target value of the flow rate, and then the PID control is performed. ing. A two-dot chain line in FIG. 8 (Comparative Example 2) shows a temporal change in the position of the valve body 31 from the beginning, that is, when the PID control is performed from the closed position to the target position. In Comparative Example 1 and Comparative Example 2, overshoot occurs, and the time until the position of the valve body 31 is stabilized is longer than that in the example. Therefore, compared with Comparative Example 1 and Comparative Example 2, the example has higher speed response and stability.

  On the other hand, as shown in FIG. 9, the control device 3 performs the second constant speed control for moving the valve body 31 at a constant moving speed from the initial position (position closer to the open position than the intermediate position) to the intermediate position. I do. Then, the control device 3 moves less than the moving speed of the valve body 31 in the second constant speed control at least partly from the intermediate position to the closed position (particularly from the position immediately before the closed position to the closed position). Deceleration control is performed to move the valve element 31 at a speed. The control device 3 presses the valve body 31 against the valve seat 28 after the valve body 31 reaches the closed position.

  In order to increase the quick response of the first valve 14, the control device 3 moves the valve body 31 at, for example, the maximum speed in the second constant speed control. Moreover, in order to reduce the impact when the valve body 31 contacts the valve seat 28, the control device 3 moves the valve body 31 at a lower moving speed than in the second constant speed control in the deceleration control. Thereby, particles generated due to contact between the valve body 31 and the valve seat 28 are reduced. If the moving speed of the valve body 31 is small, the deceleration control may be constant speed control or feedback control such as PID control.

  As described above, in the present embodiment, the valve body 31 is provided with the annular portion 34 that opens and closes the first valve 14 and the cone portion 33 that adjusts the flow rate of the processing liquid passing through the first valve 14. The electric motor 23 moves the valve body 31 between the closed position and the open position in accordance with a command from the control device 3. When the electric motor 23 moves the valve body 31, the cone part 33 and the annular part 34 move together.

  Due to the movement of the cone portion 33, the flow path area of the opening 27 (the area of the portion not occupied by the cone portion 33) continuously changes. The flow rate of the processing liquid supplied to the processing liquid nozzle 11 is automatically adjusted by the electric motor 23. When the electric motor 23 positions the valve body 31 in the closed position, the annular portion 34 contacts the valve seat 28. When the electric motor 23 positions the valve body 31 in a position other than the closed position, the annular portion 34 is Leave the valve seat 28. The supply and stop of the processing liquid to the processing liquid nozzle 11 are automatically switched by the electric motor 23. Therefore, the supply and stop of supply of the processing liquid to the processing liquid nozzle 11 and the adjustment of the flow rate of the processing liquid supplied to the processing liquid nozzle 11 can be executed by one valve (first valve 14).

  The outer peripheral surface 33a of the cone portion 33 is not in contact with the main body 25 at any position from the closed position to the open position. Therefore, due to the movement of the valve body 31, the cone portion 33 is not rubbed against the main body 25 and particles are not generated. The annular tip 34a of the annular part 34 is pressed perpendicularly to the valve seat 28 in the closed position. Therefore, particles are less likely to be generated than when a conical valve body is pressed against a conical or cylindrical valve seat. Therefore, particles generated in the flow path 30 can be reduced, and the cleanliness of the processing liquid supplied to the substrate W can be increased.

  Further, in the present embodiment, the flat annular tip 34 a is pressed vertically against the flat valve seat 28. As a result, the valve seat 28 and the annular tip 34a are in surface contact. Therefore, compared with the case where the valve body 31 and the valve seat 28 are in line contact, the flow of the processing liquid can be blocked more reliably. Furthermore, since the planes are pressed vertically, particles are less likely to be generated than when a conical valve body is pressed against a conical or cylindrical valve seat. Thereby, particles generated in the flow path 30 can be reduced.

  If the contact area between the valve body 31 and the valve seat 28 is too small, sufficient sealing performance cannot be secured. On the other hand, if the contact area between the valve body 31 and the valve seat 28 is too large, a large pressure is required to close the valve. For this reason, the contact area between the valve body 31 and the valve seat 28 is preferably as small as possible within a range in which sufficient sealing performance can be secured. In the present embodiment, since the inner diameter of the annular tip portion 34a is larger than the diameter of the opening 27, the contact between the valve seat 28 and the annular tip portion 34a is smaller than when the inner diameter of the annular tip portion 34a is equal to or smaller than the diameter of the opening 27. The area can be reduced. Therefore, it is possible to reduce particles while more reliably blocking the flow of the treatment liquid.

  Further, in the present embodiment, when the valve body 31 is arranged at a position other than the closed position, the processing liquid that has flowed into the inflow port 26 has a gap between the annular portion 34 and the valve seat 28, and the cone portion 33. And a gap between the opening 27 and the edge 27a of the opening 27. Since the flow path area between the annular portion 34 and the valve seat 28 is smaller than the flow path area of the opening 27 at the position closer to the closing position than the intermediate position, the flow rate of the processing liquid passing through the first valve 14 is reduced. Rate limiting. On the other hand, since the flow path area of the opening 27 is smaller than the flow path area between the annular portion 34 and the valve seat 28 at the position closer to the open position than the intermediate position, the process of passing through the first valve 14 is performed. Limit the flow rate of the liquid.

  The control device 3 performs first constant speed control for moving the valve element 31 at a constant moving speed from the closed position to the intermediate position. And the control apparatus 3 performs the feedback control which moves the valve body 31 based on the detected value of the 1st flow meter 15 from an intermediate position to a target position. That is, since the target position is in a range in which the flow path area of the opening 27 determines the flow rate of the processing liquid, the control device 3 determines that the flow path area between the annular portion 34 and the valve seat 28 has the flow volume of the processing liquid. The valve body 31 is quickly moved out of the rate-limiting range. Therefore, compared with the case where feedback control is performed from the beginning, the time until the measured value of the flow rate is stabilized can be shortened.

  In the present embodiment, the control device 3 performs the second constant speed control for moving the valve body 31 at a constant moving speed from the initial position (position closer to the open position than the intermediate position) to the intermediate position. And the control apparatus 3 performs the deceleration control which moves the valve body 31 with the moving speed smaller than the moving speed of the valve body 31 in 2nd constant speed control in all or one part from an intermediate position to a closed position. Thus, since the moving speed immediately before the valve body 31 contacts the valve seat 28 is reduced, the impact when the valve body 31 contacts the valve seat 28 can be reduced, and the contact between the valve body 31 and the valve seat 28 can be reduced. Can further reduce the particles generated.

Although the description of the embodiment of the present invention has been described above, the present invention is not limited to the contents of the above-described embodiment, and various modifications can be made within the scope of the present invention.
For example, in the embodiment, the case where the flow path 30 has an L-shaped cross section has been described, but the cross-sectional shape of the flow path 30 is not limited to the L shape.
In the above-described embodiment, the case where the valve seat 28 is integrated with the main body 25 has been described. However, the valve seat 28 may be a separate part from other parts that form the flow path 30.

In the above embodiment, when the electric motor 23 rotates, the valve body 31 performs a linear motion without rotating around its center line. However, the motion converting mechanism 22 has the valve body 31 around its center line. The power of the electric motor 23 may be transmitted to the valve body 31 so as to linearly move while rotating.
In the above-described embodiment, the case where the cone portion 33 has a conical shape has been described. However, the cone portion 33 may have a pyramid shape. Regardless of whether the cone portion 33 is conical or pyramidal, the tip of the cone portion 33 may not be a point but a plane orthogonal to the axial direction X1 of the cone portion 33 or may be a curved surface. There may be.

In the above embodiment, the case where the valve seat 28 and the annular tip portion 34a are both flat annular surfaces has been described. However, at least one of the valve seat 28 and the annular tip portion 34a is an annular shape having an arc-shaped cross section. It may be a curved surface.
In the above embodiment, the case where the inner diameter of the annular tip portion 34a is larger than the diameter of the opening 27 has been described, but the inner diameter of the annular tip portion 34a may be equal to or smaller than the diameter of the opening 27.

In the embodiment, the case where the feedback control is the PID control has been described. However, the feedback control is not limited to the PID control, and may be a proportional control that performs a proportional operation, or a PI control that performs a proportional operation and an integral operation. It may be.
In the above embodiment, the case where SC-1 as an example of a chemical solution and pure water as an example of a rinse solution are discharged from the same nozzle (treatment liquid nozzle 11) has been described. You may discharge from a separate nozzle. The chemical solution may be a liquid other than SC-1. The rinse liquid may be a liquid other than pure water.

In the embodiment, the case where the substrate processing apparatus 1 is an apparatus that processes a disk-shaped substrate W has been described. However, the substrate processing apparatus 1 may be an apparatus that processes a polygonal substrate W.
In the above-described embodiment, the case where the substrate processing apparatus 1 is a single-wafer type apparatus has been described. However, the substrate processing apparatus 1 may be a batch-type apparatus that collectively processes a plurality of substrates W.
In the case where the substrate processing apparatus 1 is a batch type, the substrate processing apparatus 1 includes a processing tank for storing the processing liquid and a plurality of substrates in the processing liquid in the processing tank by moving up and down while holding the plurality of substrates W. Lifter for immersing W, treatment liquid nozzle for discharging treatment liquid in the treatment tank, supply of treatment liquid to the treatment liquid nozzle, supply stop, and adjustment of flow rate of treatment liquid supplied to the treatment liquid nozzle Including an electric valve.

  Two or more of all the above-described configurations may be combined. Similarly, two or more of all the aforementioned steps may be combined.

1: substrate processing device 3: control device 4: spin chuck 11: processing liquid nozzle 12: processing liquid piping 13: first piping 14: first valve 15: first flow meter 22: motion conversion mechanism 23: electric motor 24: Rotation angle sensor 25: Main body 26: Inlet 27: Opening 27a: Opening edge 28: Valve seat 29: Outlet 30: Flow path 31: Valve body 32: Disc portion 33: Conical portion 33a: Outer peripheral surface 34: Annular part 34a: Annular tip 35: Annular groove W: Substrate X1: Axial direction Y1: Radial direction

Claims (5)

A processing liquid nozzle that discharges the processing liquid supplied to the substrate, an electric valve that performs supply and stop of the processing liquid to the processing liquid nozzle, and adjustment of a flow rate of the processing liquid supplied to the processing liquid nozzle; A control device for controlling the electric valve,
The electric valve is
An inflow port into which the processing liquid flows, an outflow port for discharging the processing liquid that has flowed into the inflow port, an opening disposed between the inflow port and the outflow port, and the inflow port through the opening. A main body provided with a flow path extending to the outlet and an annular valve seat surrounding the opening;
A closed position that contacts the valve seat and blocks the flow of the processing liquid from the inlet to the outlet, and leaves the valve seat and allows the processing liquid to flow from the inlet to the outlet through the opening. A valve body movable relative to the body between an open position and
An electric actuator that moves the valve body between the closed position and the open position and positions the valve body at an arbitrary position from the closed position to the open position in accordance with a command from the control device; Including
The valve body includes a cone part inserted into the opening, an annular part that surrounds the cone part with a space therebetween and faces the valve seat,
The cone part includes a cone-shaped outer peripheral surface that is not in contact with the main body at any position from the closed position to the open position;
The substrate processing apparatus, wherein the annular portion includes an annular tip portion that is pressed perpendicularly to the valve seat in the closed position and separates from the valve seat in a position other than the closed position.   The substrate processing apparatus according to claim 1, wherein each of the valve seat and the annular tip portion is flat.   The substrate processing apparatus according to claim 1, wherein an inner diameter of the annular tip is larger than a diameter of the opening. The substrate processing apparatus further includes a flow meter for detecting a flow rate of the processing liquid passing through the electric valve,
The control device has an intermediate position in which the radial distance from the edge of the opening to the cone portion is equal to the axial distance from the annular portion to the valve seat. Through the position closer to the open position than the intermediate position, and when moving to the target position corresponding to the target value of the flow rate of the processing liquid passing through the electric valve, from the closed position to the intermediate position, Performing a first constant speed control for moving the valve body at a constant moving speed, and performing a feedback control for moving the valve body from the intermediate position to the target position based on a detection value of the flow meter. Item 4. The substrate processing apparatus according to any one of Items 1 to 3. The substrate processing apparatus further includes a flow meter for detecting a flow rate of the processing liquid passing through the electric valve,
The control device is configured such that the radial distance from the edge of the opening to the cone portion is located closer to the open position than the intermediate position where the radial distance from the annular portion to the valve seat is equal to the axial direction. Second constant speed control for moving the valve body at a constant moving speed from the position closer to the open position than the intermediate position to the intermediate position when moving the valve body to the closed position via the intermediate position And at least a part from the intermediate position to the closed position, deceleration control is performed to move the valve body at a moving speed smaller than the moving speed of the valve body in the second constant speed control. The substrate processing apparatus as described in any one of 1-4.

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