TWI727317B - Processing liquid discharging method and processing liquid discharging device - Google Patents

Abstract

A method for discharging treatment liquid is provided, which can appropriately stop discharging treatment liquid from a nozzle and adjust the operation period of a valve. The processing liquid ejection method includes a first step and a second step. The first step is to eject the processing liquid supplied to the nozzle via the pipe from the nozzle. The second step is to change the movement speed of the valve body or the deformation speed of at least one valve provided in the piping during the operation period of the valve when the treatment liquid is stopped from the nozzle.

Description

Treatment liquid spraying method and treatment liquid spraying device

The invention relates to a treatment liquid spraying method and a treatment liquid spraying device.

Patent Document 1 discloses a coating liquid supply device that supplies a coating liquid such as a photoresist liquid to a substrate from a nozzle, and forms a coating film on the substrate. The coating liquid supply device opens and closes an opening and closing valve (here, a gas-operated valve) provided in a coating liquid supply pipe connected to a nozzle, thereby performing supply of coating liquid from the nozzle and stopping the supply of coating liquid from the nozzle. In the coating process of the coating liquid, when uneven coating of the coating liquid occurs on the substrate, the film thickness becomes uneven, which adversely affects the subsequent steps.

In this coating liquid supply device, when the opening and closing valve is closed at a certain closing speed while the coating liquid is being supplied from the nozzle, the spray width of the coating liquid is gradually narrowed in accordance with the closing speed of the opening and closing valve. Finally, the coating liquid is cut off at a certain position between the tip of the nozzle and the substrate. The liquid cut-off position is changed according to the closing speed of the opening and closing valve.

The coating liquid supply device is provided with a suction valve, and sucks back by the action of the suction valve, sucking the coating liquid higher than the liquid shutoff position back to the nozzle. The coating liquid below the liquid shutoff position faces the surface of the substrate, becomes a thin line, and drops. In addition, a plurality of droplets are generated in the interrupted portion of the coating liquid, and they fall to the substrate more slowly than the thin linear coating liquid.

The coating liquid supply device uses a camera to photograph and detect the liquid cutoff position between the nozzle tip and the substrate, and the liquid cutoff position exists in a range where coating unevenness does not occur. In this way, the closing speed of the opening and closing valve is adjusted to prevent uneven coating.

[Prior Technical Literature] [Patent Literature]

Patent Document 1: Japanese Patent Application Laid-Open No. 2000-82646.

However, in the case where the closing speed of the opening and closing valve is controlled in a slightly fixed manner during the closing period of the opening and closing valve, the control is not necessarily optimal. Specifically, when the blocking speed is determined to be a value that does not cause uneven coating, the blocking period is determined in accordance with the blocking speed, and therefore the blocking period cannot be adjusted in other ways.

It is expected that the lockout period can be adjusted for various reasons. As an example, as long as the lock period can be shortened, the responsiveness of the on-off valve can be improved. In addition, it is not necessarily expected that the locking speed is fixed.

Therefore, an object of the present invention is to provide a processing liquid ejection method and processing liquid ejection device, which can appropriately stop the ejection of the processing liquid from the nozzle and adjust the operation period of the valve.

The first aspect of the processing liquid ejection method is a processing liquid ejection method, which includes: a first step of ejecting from a nozzle the processing liquid supplied to the nozzle via a pipe; and a second step of stopping the ejection from the nozzle When the treatment liquid is discharged, the movement speed or the deformation speed of the valve body of at least one valve provided in the pipe is changed during the operation period of the valve.

The second aspect of the process liquid ejection method is that in the process liquid ejection method of the first aspect, the aforementioned at least one valve system includes: an on-off valve that switches the opening and closing of the flow path in the pipe; when the on-off valve is to be closed When the aforementioned operating speed at the time is defined as the blocking speed, in the aforementioned first In the second step, the opening and closing valve is controlled so that the closing speed in the first period in the operation period is set to be higher than the closing speed in the second period after the first period in the operation period. .

The third aspect of the process liquid ejection method is that in the second aspect of the process liquid ejection method, the opening and closing valve is a gas-actuated valve for opening and closing in response to the pressure of the gas supplied from the drive mechanism; in the second step In this case, the indicator value corresponding to the pressure of the gas is updated step by step during the operation period, the drive mechanism is controlled based on the indicator value, and the closing speed of the on-off valve is changed during the operation period.

The fourth aspect of the processing liquid ejection method is that in the third aspect of the processing liquid ejection method, the number of updates of the indicator value in the second period is greater than the number of updates in the first period.

The fifth aspect of the process liquid ejection method is that in the process liquid ejection method of any one of the first aspect to the fourth aspect, the aforementioned at least one valve system includes: a gas-actuated valve, which responds to the drive mechanism The pressure of the supplied gas is opened and closed; in the foregoing second step, proportional control, proportional integral control, or proportional integral control is performed on the difference between the pressure indicator value belonging to the target value of the gas pressure and the measured value of the gas pressure Derivative control and control of the aforementioned drive mechanism, thereby controlling the aforementioned movement speed.

The sixth aspect of the processing liquid ejection method is that in the processing liquid ejection method of any one of the first aspect to the fifth aspect, the aforementioned at least one valve system includes: a suction valve, which stops the ejection of the processing liquid When sucking back the treatment liquid in the aforementioned nozzle.

The seventh aspect of the process liquid ejection method is that in the process liquid ejection method of any one of the first aspect to the sixth aspect, the aforementioned at least one valve system includes: a gas-actuated valve, which responds to the drive mechanism The pressure of the supplied gas; in the second step, in the non-operating period until the valve body of the gas actuated valve starts to move or start to deform The driving mechanism is controlled so that the rate of change of the pressure of the gas becomes higher than the rate of change of the pressure of the gas during the operation period.

The eighth aspect of the processing liquid ejection method is that the processing liquid ejection method of any one of the first aspect to the seventh aspect includes: the third step is when the ejection of the processing liquid from the aforementioned nozzle is stopped, The imaging section photographs the flow path of the tip portion of the nozzle from a direction different from the ejection direction of the nozzle; and the fourth step is to perform a predetermined determination process based on the original image captured by the imaging section in the third step, by This determines whether the aforementioned operating speed of the aforementioned at least one valve is appropriate.

The ninth aspect of the processing liquid ejection method is that in the eighth aspect of the processing liquid ejection method, the aforementioned at least one valve system includes: an on-off valve that switches the opening and closing of the flow path in the piping; when the on-off valve is to be closed When the operating speed at the time is defined as the blocking speed, the fourth step includes the following steps: for the first image in the first image area corresponding to the flow path of the nozzle tip in the original image, and the slave The tip of the nozzle extends forward along the ejection direction of the processing liquid and corresponds to the second image of the second image area corresponding to the ejection path of the processing liquid, and calculates the image of each of the second image and the first image and the second image. The area of the image of the processing liquid in the image corresponds to a predetermined first feature amount; and applying a predetermined first determination rule to the first feature amount of the first image and the first feature amount of the second image Therefore, it is determined which of the following is the lock speed: the lock speed is appropriate, or the lock speed is higher than the appropriate speed, or the lock speed is lower than the appropriate speed.

The tenth aspect of the process liquid ejection method is that in the ninth aspect of the process liquid ejection method, the first determination rule is the following rule: when the flow path at the tip of the nozzle is not in a liquid-tight state, it is determined The closing speed of the opening and closing valve is higher than the appropriate speed; when the flow path at the tip of the nozzle is in a liquid-tight state and the treatment liquid is present in the ejection path At this time, it is determined that the aforementioned locking speed is lower than the aforementioned appropriate speed.

The eleventh aspect of the processing liquid ejection method is that in the eighth aspect of the processing liquid ejection method, the at least one valve system includes: an on-off valve that switches the opening and closing of the flow path in the pipe; when the opening and closing are closed When the valve operation speed is defined as the lock speed, in the fourth step, the flow path of the nozzle tip in the original image and the flow path extending forward from the nozzle tip along the ejection direction of the processing liquid For the image of the ejection path of the treatment liquid, the classifier judges the distinction of the lock speed, and the classifier judges which of the following is the lock speed: the lock speed is appropriate, or the lock speed is faster than the appropriate speed It is still high, or the aforementioned blocking speed is lower than the appropriate speed; the aforementioned classifier uses the sampled image of the image of the flow path at the tip of the nozzle and the aforementioned ejection path in the original image, and is pre-built by mechanical learning generate.

The twelfth aspect of the processing liquid ejection method is that in the eleventh aspect of the processing liquid ejection method, in the foregoing fourth step, the flow path corresponding to the tip of the nozzle in the original image is based on the first The first image of the image area and the second image of the second image area corresponding to the ejection path determine the distinction of the locking speed of the opening and closing valve; the classifier uses the first image and the second image Sampling images of each image are generated in advance by mechanical learning.

The thirteenth aspect of the processing liquid ejection method is that in the processing liquid ejection method of the ninth, tenth, or twelfth aspect, the first image area in the downstream side of the ejection direction of the processing liquid The end of is separated from the tip of the nozzle to the upstream side in the ejection direction of the processing liquid.

The fourteenth aspect of the processing liquid ejection method is the processing liquid ejection method of any one of the eighth aspect to the thirteenth aspect, and the aforementioned at least one valve system includes: a suction valve, which stops the ejection When processing liquid, suck back the processing liquid in the nozzle to make the end face position of the processing liquid Keep away from the tip of the nozzle; the fourth step includes the following step: for a third image corresponding to at least a part of the flow path between the end face position of the processing liquid and the tip of the nozzle in the original image For the third image of the region, a predetermined second feature quantity corresponding to the area of the image of the processing liquid is calculated; and a predetermined second determination rule is applied to the second feature quantity of the third image, thereby determining the aforementioned The operation speed of the suction valve is divided into the following: the operation speed of the suction valve is appropriate, or the operation speed of the suction valve is higher than the appropriate speed.

The fifteenth aspect of the processing liquid ejection method is that in the fourteenth aspect of the processing liquid ejection method, the second determination rule is based on at least the flow path between the end face position of the processing liquid and the tip of the nozzle When a part of the treatment liquid remains, it is determined that the operating speed of the suction valve is higher than the appropriate speed.

The sixteenth aspect of the processing liquid ejection method is in the processing liquid ejection method of any one of the eighth aspect to the thirteenth aspect, the aforementioned at least one valve system includes: a suction valve, which stops the ejection When processing the liquid, suck back the processing liquid in the nozzle to make the position of the end surface of the processing liquid away from the tip of the nozzle; in the fourth step, according to the original image and the position of the end surface of the processing liquid and the nozzle At least a part of the flow path between the front ends of the corresponding to the third image of the third image area, the classification of the operation speed of the suction valve is determined by the classifier, and the classifier determines that the operation speed of the suction valve is Which one of the following distinctions is made: the aforementioned movement speed of the aforementioned suction valve is appropriate, or the aforementioned movement speed of the aforementioned suction valve is higher than the proper speed; the aforementioned classifier uses the sampling image of the aforementioned third image and preliminarily Generated by mechanical learning.

The seventeenth aspect of the processing liquid ejection method is the processing liquid ejection method of any one of the eighth aspect to the sixteenth aspect. In the third step, after stopping the ejection of the processing liquid from the nozzle, The photographing unit photographs the flow path of the tip of the nozzle sequentially in time; The fourth step includes the following steps: averaging or accumulating a plurality of original images shot by the shooting unit to generate a derivative image; and determining whether the operating speed of the at least one valve is appropriate based on the derivative image.

The eighteenth aspect of the process liquid ejection method is the process liquid ejection method of any one of the eighth aspect to the seventeenth aspect, and further includes: a fifth step, based on the foregoing fourth step It is determined whether the operation speed of the at least one valve is appropriate, and the operation of the at least one valve in the first step is adjusted so that the operation speed becomes the appropriate speed.

The aspect of the processing liquid ejection device is a processing liquid ejection device, which is provided with: a nozzle for ejecting the processing liquid; a pipe connecting the nozzle and the processing liquid supply source to guide the processing liquid from the processing liquid supply source to The nozzle; at least one valve provided in the piping; and a control unit for making the movement speed or deformation speed of the valve body of the at least one valve at the operating speed of the at least one valve when the processing liquid is stopped from the nozzle The action period changes.

According to the first aspect of the process liquid ejection method and the aspect of the process liquid ejection device, the nozzle tip state when the ejection is stopped can be set well, and the operation period can be independently adjusted.

According to the second aspect of the process liquid ejection method, the blocking speed of the second period that is likely to affect the nozzle end state when the ejection is stopped can be set so that the state of the nozzle tip when the ejection is stopped becomes good. In addition, since the locking speed in the first period is set to be higher than that in the second period, the operation period can be shortened. In other words, the nozzle tip state can be set well and the responsiveness of the on-off valve can be improved.

According to the third aspect of the processing liquid ejection method, the operation speed can be easily controlled.

According to the fourth aspect and the fifth aspect of the treatment liquid ejection method, it is easy to stop In the second period in which the nozzle tip state at the time of stopping ejection affects, the change speed of the gas pressure can be adjusted more finely, and the closing speed of the on-off valve can be adjusted.

According to the sixth aspect of the processing liquid ejection method, the operation speed is changed, thereby contributing to achieving a good nozzle tip state.

According to the seventh aspect of the process liquid ejection method, the valve control period from the start of valve control to the end of valve operation can be shortened. In other words, the responsiveness of the valve can be improved.

According to the eighth aspect of the process liquid ejection method, the original image reflects the change in the state of the nozzle tip corresponding to the valve operating speed. Since it is determined whether the motion speed is appropriate based on such original images, it is possible to determine whether the motion speed is appropriate with high determination accuracy.

According to the ninth aspect and the tenth aspect of the process liquid ejection method, the first image and the second image reflect the change of the nozzle tip state corresponding to the closing speed of the opening and closing valve. Since the presence of the image of the treatment liquid is individually detected for the first image and the second image and the distinction of the closing speed of the on-off valve is determined, the distinction of the closing speed can be determined with high determination accuracy.

According to the eleventh aspect of the process liquid ejection method, the image of the flow path and the ejection path at the tip of the nozzle reflects the change in the state of the nozzle tip corresponding to the closing speed of the opening and closing valve. Since the classification of the locking speed is determined by learning using this kind of image, the accuracy of the determination is high.

According to the twelfth aspect of the processing liquid ejection method, the first image and the second image reflect the change of the nozzle tip state corresponding to the closing speed of the opening and closing valve. Since the classifier can learn the relationship between the distinction between the image and the locking speed of the opening and closing valve for each of the first image and the second image, the determination accuracy of the classifier can be improved.

According to the thirteenth aspect of the processing liquid ejection method, the image of the image area from the end of the first image area to the tip of the nozzle in the downstream side of the ejection direction is not used for the discrimination of the closing speed of the opening and closing valve. . The image area is difficult to specify the existence and development of the processing liquid. The area of the relationship between the closing speed of the closing valve. Therefore, the accuracy of the determination can be further improved.

According to the fourteenth aspect of the process liquid ejection method, the third image reflects the change in the nozzle tip state corresponding to the operating speed of the suction valve. Since the classification of the operating speed of the suction valve is determined based on the presence of the processing liquid in the third image, the classification of the operating speed can be appropriately determined.

According to the fifteenth aspect of the processing liquid ejection method, the distinction of the operating speed can be appropriately determined.

According to the sixteenth aspect of the process liquid ejection method, the third image reflects the change in the state of the nozzle tip corresponding to the operating speed of the suction valve. Since the classification of the movement speed is determined by learning using such a third image, the accuracy of the determination is high.

According to the seventeenth aspect of the processing liquid ejection method, since the derivative image includes a temporal change in the state of the processing liquid, the determination accuracy can be improved.

According to the eighteenth aspect of the process liquid ejection method, the valve operating speed can be adjusted to an appropriate value.

1, 1A, 1B: substrate processing unit (processing liquid ejection device)

7, 7A: Treatment liquid supply part

10: Substrate processing equipment group

11: CPU

12: Pressure setting section

13: Control signal generation part

14: Judgment Department

15: Feature calculation section

16: Prescribed Basic Judgment Department

17: Image Generation Department

18: Mechanical Learning Department

21: Ministry of Communications

22: Internet

23: server

29: Bus line

50: Photography subject area

51, 53: internal area

52: Front area

65: Camera (Photography Department)

71, 71A: On-off valve

71a, 72a: drive space

71a1, 72a1: flexible space

71a2, 72a2: gas supply space

71b, 72b2: Flow path space

72, 72A: suction valve

72b: Valve box space

72b1: Non-flow path space

73, 743, 744, 753, 754: piping

74, 74A, 75, 75A: drive mechanism

76: Treatment liquid supply source

100: Substrate processing device

110: Index area

111: Carrier table

120: Treatment area

121: Chamber (frame)

122: Moving in and out

130, 130B, 130C: control section

131: Subtractor

132: PID control unit

133: Comparison Department

140, 141, 142: control panel

151: Display

152: Input Department

161: Disk

162: ROM

163: RAM

200: Processing Department

221: Rotation Fixture

251: Nozzle

252: front end

300: Speed judging device (judging device)

710, 720: valve body

711, 721: valve body

712, 722: District divider

713, 723: elastomer

714, 724: connecting part

716: Valve seat

717, 727: Motor

741, 742, 751, 752: solenoid valve

745, 755: gas supply source

746, 756: pressure sensor

A, B, C, D: area

A1: imaginary line

AR1: Spray direction

Bx1, Bx2: Container Department

C1: Carrier

CR: Handling robot

D*: Energy rate indication value

G0: Image (original image)

G1: The first image

G2: Second image

G3: Third image

G10, G11, G12, G13: Derived images (images)

GI, Gk: image

H1, H2: gas

IR: substrate handling device (transfer robot)

K1: Judgment rules

K2: classifier

L1: Treatment liquid

L2: droplet

NN1: Neural Network

P: Substrate accepting position

P1*, P2*: pressure indication value (target value)

p1, p2: predetermined value

P1[0] to P1[5], P2[0], P1[i]: Value

PL1, PL2, PH1, PH2: reference value

PG: Program

Pm1, Pm2: measured value

Px1, Px2: compartment

t10 to t13, t20 to t22: time point

T1, T21: previous period

T2, T22: Later period

Ta1, Ta2: During valve control

Tb1, Tb2: Non-operating period

Tc1: during lockout

Tc2: During operation

TG1: Flow path

TG2: ejection path

Vx1, Vx2: Valve box part

W: substrate

△t1, △t2, △t21, △t22: time

△P: Poor

FIG. 1 is a schematic plan view for schematically showing an example of the structure of a substrate processing apparatus.

FIG. 2 is a diagram for schematically showing an example of the structure of the substrate processing unit.

Fig. 3 is a cross-sectional view schematically showing an example of the structure of the on-off valve.

Fig. 4 is a cross-sectional view schematically showing an example of the structure of the suction valve.

Fig. 5 is a diagram showing an example of the relationship between the nozzle tip state and the closing speed when the ejection is stopped.

Fig. 6 is a graph showing an example of pressure indication value and pressure measurement value.

Fig. 7 is a flowchart showing an example of the operation of the pressure setting unit.

Fig. 8 is a graph showing an example of the pressure indication value and the pressure measurement value.

Fig. 9 is a graph showing an example of the pressure indication value and the pressure measurement value.

Fig. 10 is a flowchart showing an example of the operation of the pressure setting unit.

Fig. 11 is a graph showing an example of pressure indication value and pressure measurement value.

Fig. 12 is a functional block diagram for schematically showing an example of the internal structure of the control unit.

Fig. 13 is a graph showing an example of the pressure indication value and the pressure measurement value.

Fig. 14 is a graph showing an example of the pressure indication value and the pressure measurement value.

Fig. 15 is a graph showing an example of the pressure indication value and the pressure measurement value.

Fig. 16 is a graph showing an example of pressure indication value and pressure measurement value.

Fig. 17 is a graph showing an example of pressure indication value and pressure measurement value.

FIG. 18 is a diagram for schematically showing an example of the configuration of the substrate processing unit.

FIG. 19 is a diagram for schematically showing an example of the configuration of the substrate processing unit.

FIG. 20 is a diagram for schematically showing an example of the internal structure of the control unit.

FIG. 21 is a flowchart for showing an example of the operation of the substrate processing unit.

FIG. 22 is a diagram for graphically showing an example of the relationship between the nozzle tip state when the ejection is stopped and the closing speed of the on-off valve.

FIG. 23 is a diagram for schematically showing an example of the internal structure of the control unit.

FIG. 24 is a flowchart for showing an example of the operation of the substrate processing unit.

FIG. 25 is a diagram for graphically showing an example of the relationship between the nozzle tip state when the ejection is stopped and the division of the closing speed of the opening and closing valve.

FIG. 26 is a schematic diagram showing an example of a model of a neural network.

FIG. 27 is a diagram for graphically showing an example of the relationship between the state of the nozzle tip when the ejection is stopped and the operation speed of the suction valve.

FIG. 28 is a flowchart for showing an example of the operation of the substrate processing unit.

Fig. 29 is a diagram schematically showing a configuration example of another embodiment of the control unit.

Fig. 30 is a diagram schematically showing a configuration example of another embodiment of the control unit.

Hereinafter, the embodiment will be described with reference to the drawings. The following embodiment is an example of a substrate processing apparatus, and is not an example for limiting the technical scope of the substrate processing apparatus. In addition, in the drawings referred to below, for ease of understanding, the size and number of each part may be exaggerated or simplified. In addition, in each figure, the same reference number is attached|subjected to the part which has the same structure and function, and the overlapping description is abbreviate|omitted in the following description. The up-down direction is the vertical direction, and is upward with respect to the substrate side of the spin chuck.

(First Embodiment)

(1) Configuration of substrate processing apparatus 100

The configuration of the substrate processing apparatus 100 will be described with reference to FIG. 1. FIG. 1 is a plan view for schematically showing an example of the structure of a substrate processing apparatus 100. As shown in FIG. The substrate processing apparatus 100 includes a substrate processing unit 1.

The substrate processing apparatus 100 is a system for processing a plurality of substrates W such as semiconductor wafers. The surface shape of the substrate W is slightly circular. The substrate processing apparatus 100 includes a plurality of substrate processing units 1. The substrate processing apparatus 100 can process the substrates W piece by piece and continuously in each substrate processing unit 1, and can process a plurality of substrates W in parallel by the plurality of substrate processing units 1.

The substrate processing apparatus 100 is provided with a plurality of areas (processing blocks) arranged side by side, and specifically includes an indexer cell 110, a processing area 120, and a control unit 130. The control unit 130 controls the index area 110 And various action mechanisms included in the processing area 120 and so on.

<Index area 110>

The index area 110 is an area for transferring the unprocessed substrate W received from the outside of the device to the processing area 120, and transporting the unprocessed substrate W received from the processing area 120 to the outside of the device. The index area 110 is provided with: a carrier stage 111 for placing a plurality of carriers (carrier) C1; and a substrate transport device (ie, transfer robot) IR for performing the substrate W relative to each carrier Move in and move out of C1.

The carrier C1 that has accommodated a plurality of substrates W is carried in from the outside of the apparatus by OHT (Overhead Hoist Transfer) or the like, and is placed on the carrier table 111. Unprocessed substrates W are taken out piece by piece from the carrier C1 and processed inside the device, and the processed substrates W that have finished processing inside the device are again housed in the carrier C1. The carrier C1 accommodating the processed substrate W is carried out to the outside of the device by OHT or the like. In this way, the carrier stage 111 functions as a substrate stacking section for stacking the unprocessed substrate W and the processed substrate W. In addition, as the form of the carrier C1, it can be a FOUP (Front Opening Unified Pod; front opening wafer transfer box) for storing the substrate W in a closed space, or it can be a SMIF (Standard Mechanical Inter Face; standard manufacturing interface) The box may also be an OC (Open Cassette) in which the contained substrate W is in contact with the outside air.

The transfer robot IR system is equipped with: a plurality of hands (for example, four), which support the substrate W from below, whereby the substrate W can be held in a horizontal posture (the main surface of the substrate W is a horizontal posture); and a plurality of arms , Department of moving multiple hands respectively. The transfer robot IR takes out the unprocessed substrate W from the carrier C1 that has been placed on the carrier table 111, and transfers the taken out substrate W to the transfer robot CR (described later) in the substrate transfer position P. In addition, the transfer robot IR receives the processed substrate W from the transfer robot CR in the substrate transfer position P, and stores the received substrate W in the carrier C1 that has been placed on the carrier table 111. The IR system of the transfer robot can simultaneously use multiple hands and transfer substrates W.

<Processing area 120>

The processing area 120 is an area for processing the substrate W. The processing area 120 is provided with a plurality of substrate processing units 1 and a transfer robot CR, which carries in and unloads the substrates W to and from the plurality of substrate processing units 1. The transfer robot CR and the control unit 130 are substrate transfer devices. Here, a plurality of (for example, three) substrate processing units 1 are stacked in the vertical direction, and constitute one substrate processing apparatus group 10. In addition, a plurality of (four in the example of the drawing) substrate processing apparatus group 10 is arranged in a cluster shape (house shape) so as to surround the transfer robot CR. Therefore, a plurality of substrate processing units 1 are respectively arranged around the transfer robot CR. The substrate processing unit 1 holds the substrate arranged on the upper side (upper side in the vertical direction) of the unshown autorotating jig in a contactable and contact-releasable manner by the autorotating jig, and the autorotating jig is centered on a predetermined rotation axis. While rotating, the substrate is subjected to predetermined processing (for example, chemical solution processing, rinse processing, or drying processing, etc.).

The conveying robot CR is a robot for conveying the substrate W while supporting the substrate W unilaterally. The transfer robot CR takes out the processed substrate W from the designated substrate processing unit 1 and transfers the taken-out substrate W to the transfer robot IR in the substrate transfer position P. In addition, the transfer robot CR receives the unprocessed substrate W from the transfer robot IR in the substrate transfer position P, and transfers the received substrate W to the designated substrate processing unit 1. Similar to the transfer robot IR, the transfer robot CR also has a plurality of (for example, four) hands; and a plurality of arms, which move the plurality of hands, respectively. The transfer robot CR system can simultaneously use a plurality of hands to transfer the substrate W.

Each substrate processing unit 1 is provided with a chamber 121 (that is, a frame 121), and the chamber 121 forms a processing space inside. The housing 121 is formed with a carry-in/outlet 122, and the carry-in/outlet 122 is used for the transfer robot to insert the hand of the transfer robot into the inside of the frame 121. A shutter (not shown) is provided at the carry-in and carry-out exit 122, and the shutter can be opened and closed according to the control of the control unit 130. The shutter is opened when the substrate W is carried into and out of the housing 121, and is closed when the substrate W is processed. The substrate processing unit 1 is arranged in the space where the transfer robot CR is arranged so that the carry-out and carry-out entrance 122 is opposed to each other. About the specifics of the substrate processing unit 1 The composition of sex is described later.

<Control Unit 130>

The control unit 130 controls the actions of each of the transfer robot IR, the transfer robot CR, and the group of substrate processing units 1. As the configuration of the hardware of the control unit 130, a computer similar to a general computer can be used. That is, the control unit 130 combines, for example, a CPU (Central Processing Unit; central processing unit) 11, a ROM (Read Only Memory) 162 that belongs to a memory dedicated for reading, and a memory that can be read and written freely. The RAM (Random Access Memory; random access memory) 163 and the disk 161 are electrically connected to the bus line 29 to form a structure. The CPU 11 performs various calculations, the ROM 162 stores the basic programs, and the RAM 163 memory Various information, disk 161 is pre-stored program PG and data. The display portion 151 such as the liquid crystal panel and the input portion 152 such as the keyboard are also electrically connected to the bus line 29. The disk 161 also stores a recipe (not shown), etc., which are used to specify the processing content and processing sequence of the substrate W.

In the control section 130, the CPU 11 as the main control section performs arithmetic processing in accordance with the sequence written in the program PG, thereby realizing various functional sections for controlling each section of the substrate processing apparatus 100. Specifically, the CPU 11 operates as various functional units such as the pressure setting unit 12 and the control signal generating unit 13 described later. In addition, part or all of the functional units implemented in the control unit 130 may also be implemented in hardware by a dedicated logic circuit or the like.

(2) Configuration of substrate processing unit 1

FIG. 2 is a diagram for schematically showing an example of the substrate processing unit (that is, the processing liquid ejection device) 1. The substrate processing unit 1 can, for example, supply a processing liquid L1 to a main surface (also referred to as an upper surface) of a substrate W that is rotating in a plane, thereby applying various treatments to the upper surface of the substrate W. As the treatment liquid L1, for example, pure water can be used. In addition, the treatment liquid L1 is not limited to pure water, and may be functional water such as carbonated water, ionized water, ozone water, or reduced water (hydrogen water). Alternatively, the treatment liquid L1 can also be ammonia water, a mixed liquid of ammonia water and hydrogen peroxide water, a mixed liquid of hydrochloric acid and hydrogen peroxide water, hydrofluoric acid, sulfuric acid and peroxygen. A mixture of hydrogen water, a mixture of sublimable substances and solvents, or a chemical solution such as isopropyl alcohol.

As shown in FIG. 2, the substrate processing unit 1 includes, for example, a processing unit 200 for processing the substrate W with a processing liquid L1 while rotating the held substrate W; and a processing liquid supply unit 7 for processing the processing unit 200 Supply the processing liquid L1; and the control unit 130.

(2-1) Processing part 200

The processing unit 200 is provided with a rotation jig 221 and a nozzle 251 in the housing 121. The processing unit 200 rotates the substrate W with a predetermined rotation axis as the center while holding the substrate W from below by the rotation jig (that is, the rotation holding mechanism) 221. The processing unit 200 supplies the processing liquid L1 to the upper surface of the substrate W from the nozzle 251 and processes the substrate W.

The rotation jig 221 is provided with: a disc-shaped spin base with a slightly horizontal main surface; and a rotation mechanism that passes through the center of the rotation base and extends the rotation base in the vertical direction. The rotation axis rotates as the center. A plurality of holding pins are erected on the peripheral edge of the rotation base, and the plurality of holding pins hold the peripheral edge of the substrate W in a contactable and contact-releasable manner. The rotation jig 221 holds the peripheral edge portion of the substrate W with a plurality of holding pins, thereby holding the substrate W in a slightly horizontal posture such that the upper surface of the rotation base and the lower surface of the substrate W face each other. The center of the held substrate W is located on the rotation axis of the rotation base. The rotation jig 221 rotates the rotation base with the rotation axis as the center in this state, thereby rotating the substrate W with the rotation axis as the center.

The nozzle 251 is arranged above the substrate W held by the rotation jig 221, and the processing liquid L1 is supplied from the processing liquid supply unit 7 to the nozzle 251. The nozzle 251 ejects the supplied processing liquid L1 to the upper surface of the substrate W rotated by the rotation jig 221. The upper surface of the substrate W is processed by the processing liquid L1.

The nozzle 251 is moved back and forth between the processing position and the retracted position by a predetermined moving mechanism (not shown). As illustrated in Figure 2, the processing position is that the nozzle 251 is rotated in the vertical direction and The position where the substrate W held by the jig 221 faces, and the retracted position is a position where the nozzle 251 does not face the substrate W held by the rotation jig 221 in the vertical direction. The operations of loading the substrate W into the processing unit 200 and unloading the substrate W from the processing unit 200 are performed by the transfer robot CR in a state where the nozzle 251 has stopped at the retracted position. The substrate W carried into the processing unit 200 is held by the rotation jig 221 in a contactable and contact-releasable manner.

(2-2) Treatment liquid supply part 7

The processing liquid supply unit 7 includes an on-off valve 71, a suction valve 72, a pipe 73, and drive mechanisms 74 and 75. The pipe 73 connects the processing liquid supply source 76 and the nozzle 251, and guides the processing liquid L1 supplied from the processing liquid supply source 76 to the nozzle 251.

The on-off valve 71 is provided in the middle of the path of the pipe 73 to switch the opening and closing of the flow path in the pipe 73. In the example of FIG. 2, the opening and closing valve 71 is a gas-actuated valve for opening and closing in response to the pressure of the predetermined gas H1 supplied from the driving mechanism 74. For example, the on-off valve 71 is a normally closed type gas-actuated valve that opens the flow path in the pipe 73 when the gas H1 is supplied, and closes the pipe 73 when the gas H1 is discharged. The flow path within.

FIG. 3 is a cross-sectional view for schematically showing an example of the structure of the on-off valve 71. The on-off valve 71 has a container part Bx1, a valve box part Vx1, and a partition part Px1. The container part Bx1 and the partition part Px1 form a drive space 71a, and the valve box part Vx1 and the partition part Px1 form a flow path space 71b. The partition Px1 is a member for partitioning the drive space 71a and the flow path space 71b.

A partition 712 is provided in the container portion Bx1, and the partition 712 partitions the driving space 71a into an elastic space 71a1 and a gas supply space 71a2. An elastic body 713 is arranged in the elastic space 71a1, and the elastic body 713 presses the partition plate 712 to the side of the flow path space 71b. The elastic body 713 is, for example, a leaf spring. In addition, the partition 712 is arranged to be slidable in the pressing direction of the elastic body 713.

The partition 712 is connected to one end of the connecting portion 714. The connecting portion 714 has, for example, a rod-like shape, and slidably penetrates the partition portion Px1. The other end of the connecting portion 714 is tied to the flow path space 71b is connected to the valve body 711. The flow path space 71 b is a space that communicates with the flow path of the pipe 73 and forms a part of the flow path of the pipe 73.

The gas supply space 71a2 is supplied with gas H1 by the drive mechanism 74 mentioned later. When the pressure of the gas H1 in the gas supply space 71a2 (hereinafter referred to as the supply pressure) becomes higher than the reference value PL1, the partition 712 starts to move toward the elastic body 713 side. The partition 712 further moves toward the elastic body 713 as the supply pressure of the gas H1 increases, and stops at a position corresponding to the supply pressure. However, when the supply pressure of the gas H1 becomes higher than the reference value PH1, the elastic body 713 does not substantially elastically deform any further, and the partition 712 does not move further. Alternatively, in the case where a stopper is provided in the elastic space 71a, when the supply pressure of the gas H1 coincides with the reference value PH1, the partition plate 712 abuts against the stopper. Of course, the reference value PH1 is higher than the reference value PL1.

Since the valve body 711 is connected to the partition 712 via the connecting portion 714, it moves toward the driving space 71a in response to the movement of the partition 712. By this movement, the flow path through the on-off valve 71 is opened in the flow path space 71b. That is, the opening of the valve seat 716 formed in the valve box portion Vx1 is opened. Here, when the supply pressure becomes higher than the reference value PH1, the valve body 711 opens the flow path sufficiently.

Conversely, when the gas H1 in the gas supply space 71a2 is discharged by the driving mechanism 74 and the supply pressure is lower than the reference value PH1, the partition 712 and the valve body 711 start to move in the direction of closing the on-off valve 71. When the supply pressure is lower than the reference value PL1, the valve body 711 returns to its original position and closes the opening of the valve seat 716. That is, the on-off valve 71 is closed.

The driving mechanism 74 drives the on-off valve 71. The driving mechanism 74 is, for example, an electric pneumatic regulator, and includes a solenoid valve 741 for air supply and a solenoid valve 742 for exhaust. The solenoid valve 741 is provided in the middle of the path of the pipe 743 to switch the opening and closing of the flow path in the pipe 743. The pipe 743 is a pipe for connecting the gas supply source 745 and the gas supply space 71 a 2 of the on-off valve 71. By opening the solenoid valve 741, the gas H1 from the gas supply source 745 is supplied to the gas supply space 71a2 of the on-off valve 71. Thereby, the gas H1 in the gas supply space 71a2 is supplied The pressure increases. The gas supply source 745 has, for example, a bottle, which stores high-pressure gas H1; and a valve (also called a pressure regulator), which reduces the pressure of the high-pressure gas H1 derived from the bottle to a certain value. . The gas supply source 745 may also be provided outside the substrate processing apparatus 100.

The solenoid valve 742 is provided in the middle of the path of the pipe 744 to switch the opening and closing of the flow path in the pipe 744. One end of the pipe 744 is connected to the pipe 743 between the solenoid valve 741 and the on-off valve 71, and the other end of the pipe 744 is connected to an exhaust part (not shown). When the solenoid valve 742 is opened, the gas H1 in the gas supply space 71a2 of the on-off valve 71 flows through a part of the pipe 743 and the pipe 744 and is discharged to the exhaust part. Thereby, the supply pressure of the gas H1 in the gas supply space 71a2 is reduced.

The opening and closing of the solenoid valves 741 and 742 is controlled by the control unit 130. In the example of FIG. 2, a control board 140 is provided in the substrate processing unit 1. The control board 140 has a driving circuit for driving the solenoid valve 741 and a driving circuit for driving the solenoid valve 742. The control unit 130 outputs a control signal for controlling the opening and closing of the solenoid valves 741 and 742 at an appropriate duty to the control board 140. The control board 140 makes the driving current flow to the solenoid valves 741 and 742 according to the control signal. The solenoid valves 741 and 742 are each opened and closed at an appropriate energy rate, whereby the drive mechanism 74 can supply the gas H1 to the gas supply space 71a2 of the opening and closing valve 71 at a desired supply pressure.

In the example of FIG. 2, a pressure sensor 746 is provided in the substrate processing unit 1. The pressure sensor 746 measures the pressure of the gas H1 in the pipe 743 between the solenoid valve 741 and the on-off valve 71 and outputs the measured value Pm1 to the control unit 130. For example, the pressure sensor 746 has a diaphragm and a pressure-sensitive element, and the pressure of the gas H1 is measured by detecting the deformation of the diaphragm corresponding to the pressure of the gas H1 by the pressure-sensitive element. Since the pressure of the gas H1 in the pipe 743 between the solenoid valve 741 and the on-off valve 71 is ideally equal to the supply pressure of the gas H1 in the gas supply space 71a2, the measured value Pm1 can be said to indicate the supply pressure of the gas H1. The control unit 130 controls the opening and closing of the solenoid valves 741 and 742 so that the measured value Pm1 approaches the target value.

As mentioned above, since the position of the valve body 711 of the on-off valve 71 depends on the gas H1 Because of the magnitude of the supply pressure, the control unit 130 controls the rate of change of the supply pressure of the gas H1, thereby controlling the operating speed of the on-off valve 71 (also referred to as the opening and closing speed).

The suction valve 72 is provided in the middle of the path of the pipe 73 between the on-off valve 71 and the nozzle 251. The suction valve 72 moves (suctions) the processing liquid L1 in the nozzle 251 to the suction valve 72 side when the discharge of the processing liquid L1 is stopped. Thereby, the position of the end surface of the processing liquid L1 in the nozzle 251 is away from the front end 252 of the nozzle 251. In the example of FIG. 2, the suction valve 72 is a gas-actuated valve for performing a suction operation in response to the pressure of the predetermined gas H2 supplied from the driving mechanism 75. For example, the suck-back valve 72 is a gas-actuated valve of a form in which the processing liquid L1 is sucked back in a state where the gas H2 has been discharged. In addition, the gas H2 may be the same as the gas H1.

FIG. 4 is a cross-sectional view for schematically showing an example of the structure of the suction valve 72. The suction valve 72 has a container part Bx2, a valve box part Vx2, and a partition part Px2. The container part Bx2 and the partition part Px2 form a drive space 72a, and the valve box part Vx2 and the partition part Px2 form a valve box space 72b. The partition Px2 is a member used to partition the drive space 72a and the valve box space 72b.

A partition 722 is provided in the container portion Bx2, and the partition 722 partitions the driving space 72a into an elastic space 72a1 and a gas supply space 72a2. An elastic body 723 is provided in the elastic space 72a1, and the elastic body 723 presses the partition plate 722 to the side of the gas supply space 72a2. The elastic body 723 is, for example, a leaf spring. In addition, the partition plate 722 is arranged to be slidable in the pressing direction of the elastic body 723.

The partition 722 is connected to one end of the connecting portion 724. The connecting portion 724 has, for example, a rod-like shape, and slidably penetrates the partition portion Px2. The other end of the connecting portion 724 is connected to the valve body 721 in the valve box space 72b. The valve body 721 also functions as a partition for partitioning the valve box space 72b into a non-flow path space 72b1 and a flow path space 72b2. The flow path space 72 b 2 is connected to the flow path of the pipe 73 and functions as a part of the flow path of the pipe 73. In addition, the valve body 721 can be deformed along with the movement of the partition 722, and the volume of the flow path space 72b2 changes in response to the deformation of the valve body 721.

The gas supply space 72a2 is supplied with gas H2 by the drive mechanism 75 mentioned later. When the pressure of the gas H2 in the gas supply space 72a2 (hereinafter referred to as the supply pressure) becomes higher than the reference value PL2, the partition plate 722 starts to move toward the elastic body 723 side. The partition 722 further moves toward the elastic body 723 as the supply pressure of the gas H2 increases, and stops at a position corresponding to the supply pressure. However, when the supply pressure of the gas H2 becomes higher than the reference value PH2, the elastic body 723 will not substantially be further elastically deformed, and the partition 722 will not move further. Alternatively, in the case where a stopper is provided in the elastic space 72a1, when the supply pressure of the gas H2 coincides with the reference value PH2, the partition plate 722 abuts against the stopper. Of course, the reference value PH2 is higher than the reference value PL2.

Since the valve body 721 is connected to the partition 722 via the connecting portion 724, it deforms as the partition 722 moves. More specifically, the valve body 721 is deformed to reduce the volume of the flow path space 72b2. Here, when the supply pressure of the gas H2 exceeds the reference value PH2, the deformation of the valve body 721 is substantially ended.

Conversely, when the gas H2 in the gas supply space 72a2 is discharged by the driving mechanism 75 and the supply pressure is lower than the reference value PH2, the partition 722 starts to move toward the gas supply space 72a2 side. Along with this, the valve body 721 starts to deform in a direction in which the volume of the flow path space 72b2 increases. Thereby, the volume of the flow path in the suction valve 72 is increased. In addition, when the supply pressure of the gas H2 is lower than the reference value PL2, the valve body 721 returns to its original shape. Due to the increase in the volume of the flow path, the processing liquid L1 between the suction valve 72 and the nozzle 251 is sucked back to the suction valve 72 side (suction operation).

The driving mechanism 75 drives the suction valve 72. The drive mechanism 75 is, for example, an electro-pneumatic regulator, and has a solenoid valve 751 for air supply and a solenoid valve 752 for exhaust. The solenoid valve 751 is provided in the middle of the path of the pipe 753 to switch the opening and closing of the flow path in the pipe 753. The pipe 753 is a pipe for connecting the gas supply source 755 and the gas supply space 72 a 2 of the suction valve 72. By opening the solenoid valve 751, the gas H2 from the gas supply source 755 is supplied to the gas supply space 72a2 of the suction valve 72. Thereby, the supply pressure of the gas H2 in the gas supply space 72a2 increases. Gas supply source 755 The system has, for example, a bottle body that stores high-pressure gas H2; and a valve (also referred to as a pressure regulator) that reduces the pressure of the high-pressure gas H2 derived from the bottle body to a certain value. The gas supply source 755 may also be provided outside the substrate processing apparatus 100.

The solenoid valve 752 is provided in the middle of the path of the pipe 754 to switch the opening and closing of the flow path in the pipe 754. One end of the pipe 754 is connected to the pipe 753 between the solenoid valve 751 and the suction valve 72, and the other end of the pipe 754 is connected to an unshown exhaust part. When the solenoid valve 752 is opened, the gas H2 in the gas supply space 72a2 of the suction valve 72 flows through a part of the pipe 753 and the pipe 754 and is discharged to the exhaust part. Thereby, the supply pressure of the gas H2 in the gas supply space 72a2 is reduced.

The opening and closing of the solenoid valves 751 and 752 is controlled by the control unit 130. Specifically, the control board 140 has a driving circuit for driving the solenoid valve 751 and a driving circuit for driving the solenoid valve 752. The control unit 130 outputs a control signal for controlling the opening and closing of the solenoid valves 751 and 752 at an appropriate energy rate to the control board 140. The control board 140 makes the driving current flow to the solenoid valves 751 and 752 according to the control signal. The solenoid valves 751 and 752 are each opened and closed at an appropriate energy rate, whereby the drive mechanism 75 can supply the gas H2 to the gas supply space 72a2 of the suction valve 72 at a desired supply pressure.

In the example of FIG. 2, a pressure sensor 756 is provided in the substrate processing unit 1. The pressure sensor 756 measures the pressure of the gas H2 in the pipe 753 between the solenoid valve 751 and the suction valve 72, and outputs the measured value Pm2 to the control unit 130. An example of the structure of the pressure sensor 756 is the same as that of the pressure sensor 746. Since the pressure of the gas H2 in the pipe 753 between the solenoid valve 751 and the suction valve 72 is ideally equal to the supply pressure of the gas H2 in the gas supply space 72a2, the measured value Pm2 can be said to indicate the supply pressure of the gas H2 . The control unit 130 controls the opening and closing of the solenoid valves 751 and 752 so that the measured value Pm2 approaches the target value.

As described above, since the degree of deformation of the valve body 721 of the suction valve 72 depends on the supply pressure of the gas H2, the control unit 130 controls the rate of change of the supply pressure of the gas H2, thereby controlling the suction valve 72 action speed. For example, the control unit 130 controls the supply of gas H2 The speed of pressure reduction can thereby control the operating speed of the suction valve 72 during the suction operation.

(3) Outline of the operation of the substrate processing unit

Next, an example of the overall operation of the substrate processing unit 1 will be briefly described. First, the control unit 130 opens the shutter (not shown) of the housing 121, controls the transfer robot CR to carry the substrate W into the housing 121, and places the substrate W on the rotation jig 221. Next, the control unit 130 controls the transfer robot CR to draw the hand of the transfer robot CR from the inside of the housing 121 and close the shutter. This completes the loading operation of the substrate W.

Next, the control unit 130 rotates the autorotating jig 221 and controls the drive mechanism 74 to open the on-off valve 71. Thereby, the processing liquid L1 flows from the processing liquid supply source 76 inside the pipe 73 and is ejected from the nozzle 251 toward the upper surface of the substrate W. The processing liquid L1 deposited on the upper surface of the substrate W receives the centrifugal force caused by the rotation to spread on the upper surface of the substrate W and scatter from the periphery of the substrate W. The processing liquid L1 acts on the upper surface of the substrate W, thereby processing the substrate W.

When a sufficient processing time has elapsed, the control unit 130 controls the drive mechanism 74 to close the on-off valve 71, and controls the drive mechanism 75 to cause the suction valve 72 to perform a suction operation. Thereby, the ejection of the processing liquid L1 from the nozzle 251 is stopped. In addition, by performing a sucking-back operation, the processing liquid L1 moves to the sucking-back valve 72 side in the interior of the nozzle 251. Thereby, it is possible to reduce the possibility of the occurrence of sagging (falling of droplets) of the treatment liquid L1. By stopping the ejection of the processing liquid L1, the processing of the substrate W is substantially completed. After that, other treatments may be appropriately performed, for example, drying treatment may be appropriately performed. For example, the rotation speed of the substrate W may be increased, and the processing liquid on the upper surface of the substrate W may be scattered to the outside, thereby drying the substrate W.

(3.1) The operating speed of the valve and the state of the processing liquid at the tip of the nozzle

In addition, when the operating speeds of the on-off valve 71 and the suction valve 72 at the time of stopping the discharge of the processing liquid L1 are not appropriate, the discharge of the processing liquid L1 is not properly stopped. For example, the processing liquid L1 may drop from the tip 252 of the nozzle 251 in a dripping state. In this case, it is difficult to say that the nozzle 251 when the spray is stopped The state of the processing liquid L1 (hereinafter referred to as the nozzle tip state) of the tip portion is good. In addition, the so-called operating speed here can grasp the moving speed of the valve body 711 or the deformation speed of the valve body 721. In addition, in the following, the operating speed of the on-off valve 71 when the discharge of the processing liquid L1 is stopped is also referred to as the closing speed.

The state of the nozzle tip when the ejection is stopped depends on the closing speed of the on-off valve 71 and the operating speed of the suction valve 72. However, when the closing speed of the on-off valve 71 is not appropriate, even if the operating speed of the suction valve 72 is adjusted, the operation speed of the suction valve 72 may not be satisfactory. The ground is set to the state of the nozzle tip. Therefore, first, the closing speed of the on-off valve 71 will be described below.

FIG. 5 is a diagram for graphically showing an example of the relationship between the nozzle tip state and the closing speed of the on-off valve 71. There are three types of nozzle tip states shown in the uppermost part of the graph in FIG. 5. In the second paragraph from the top, whether the tip of the three nozzles shown in the top stage is in good condition is described. The correspondence relationship between the tip states of the three nozzles displayed on the uppermost stage and the closing speed of the on-off valve 71 is displayed in the lowermost stage. As described in detail later, the closing speed of the on-off valve 71 is adjusted by the drive mechanism 74.

As shown in FIG. 5, the state of the nozzle tip when the ejection is stopped varies according to the closing speed of the on-off valve 71. When the closing speed of the on-off valve 71 is too low, after the nozzle 251 stops discharging the processing liquid L1, the liquid droplets L2 of the processing liquid L1 temporarily continue to fall (drop intermittently). That is, the state of the tip of the nozzle becomes a poor state.

When the closing speed of the on-off valve 71 is too high, the processing liquid L1 remains in the state of the droplet L2 at the tip of the nozzle 251 by a so-called water hammer. That is, the liquid droplet L2 is separated from the processing liquid L1 existing in a liquid-tight state along the inside of the nozzle 251 and adheres to the inner surface of the nozzle 251 on the front end side. Such droplets L2 will fall onto the substrate W later. That is, the state of the tip of the nozzle becomes a poor state.

When the closing speed of the on-off valve 71 is appropriate, the tip of the nozzle 251 becomes a liquid-tight state substantially caused by the processing liquid L1, and the liquid droplet L2 will not temporarily continue dripping after stopping. also That is, the state of the nozzle tip becomes a better state.

In addition, the inventors discovered that the nozzle tip state is more likely to depend on the closing speed of the opening and closing valve 71 at the end of the closing period of the opening and closing valve 71 than the closing speed at the beginning of the closing period of the opening and closing valve 71. In addition, the locked period referred to here refers to a period during which the valve body 711 of the on-off valve 71 starts to move toward the valve seat 716 until it stops.

(3-2) Locking control of on-off valve

In addition, the control unit 130 changes the closing speed of the opening and closing valve 71 during the closing period of the opening and closing valve 71. That is, in the substrate processing unit 1 of this example, the on-off valve 71 is not closed at the device-specific closing speed. As a more specific example, the control unit 130 sets the initial closing speed to be higher than the final closing speed. The initial closing speed is less likely to affect the nozzle tip state when the ejection is stopped, and the final closing speed is easy. Affects the state of the nozzle tip when spraying is stopped. In the example of FIG. 2, since the on-off valve 71 is a gas-actuated valve, the control unit 130 changes the rate of change of the supply pressure of the gas H1 supplied to the on-off valve 71 during the lock period, thereby making the lock rate as described above地变。 Land changes. Hereinafter, a more specific example of the control unit 130 will be described.

As shown in FIG. 1, the control unit 130 includes a pressure setting unit 12 and a control signal generating unit 13. The pressure setting unit 12 sets a target value (hereinafter referred to as a pressure instruction value) P1* for the supply pressure of the gas H1 supplied to the on-off valve 71, and outputs the pressure instruction value P1* to the control signal generation unit 13. The control signal generating unit 13 generates control signals for the solenoid valves 741 and 742 according to the pressure instruction value P1* in such a way that the supply pressure of the gas H1 approaches the pressure instruction value P1*. The solenoid valves 741 and 742 are opened and closed according to their respective control signals.

The pressure setting unit 12 gradually decreases the pressure instruction value P1* from a value higher than the reference value PH1 to a value lower than the reference value PL1 when the on-off valve 71 is switched from the open state to the closed state. Fig. 6 is a graph showing an example of the pressure indication value P1* and the measured value Pm1 of the supply pressure of the gas H1. Here, from the time point t10 at which the pressure indication value P1* starts to decrease to the time point t10 at which the pressure indication value P1* starts to decrease The period from the time point t13 when the quantity Pm1 is lower than the reference value PL1 is called the valve control period Ta1, and the period from the time point t10 to the time point t11 at which the pressure indication value P1* is lower than the reference value PH1 is called the valve control period Ta1. The non-operation period Tb1 is the period from the time point t11 to the time point t13 as a blocking period Tc1.

In the example of FIG. 6, the pressure indication value P1* and the measurement value Pm1 are initially higher than the reference value PH1 and are substantially the same. The reason for this is that the solenoid valves 741 and 742 are controlled in such a way that the pressure indication value P1* is set to a value higher than the reference value PH1 at the initial time and the measured value Pm1 is close to the pressure indication value P1*. Since the measured value Pm1 is higher than the reference value PH1, the on-off valve 71 is initially opened, and the processing liquid L1 is ejected from the nozzle 251 toward the upper surface of the substrate W.

In the example of FIG. 6, at time t10, the pressure setting unit 12 updates the pressure instruction value P1* to the value P1[0]. The value P1[0] is a value higher than the reference value PL1 and lower than the reference value PH1. More specifically, the value P1[0] is a value smaller than the average value of the reference value PL1 and the reference value PH1. When the pressure indication value P1* is updated to the value P1[0], the solenoid valves 741 and 742 are controlled so that the supply pressure of the gas H1 approaches the value P1[0], so the supply pressure of the gas H1 is over time And reduce. Therefore, in FIG. 6, the measured value Pm1 decreases with the passage of time after the time point t10. Next, when the measured value Pm1 is lower than the reference value PH1, the valve body 711 of the on-off valve 71 starts to move. In other words, the on-off valve 71 starts the closing operation.

The non-operation period Tb1 is a period after the pressure instruction value P1* is lowered until the valve body 711 of the on-off valve 71 starts to move, and it is desirable that the non-operation period Tb1 be short. In the example of FIG. 6, the value P1[0] is set to a value close to the reference value PL1. In addition, the pressure setting unit 12 does not gradually decrease the pressure instruction value P1* to the value P1[0] over time during the non-operating period Tb1, but at the start time point (time point of the non-operating period Tb1). In t10), the pressure indication value P1* is reduced to the value P1[0]. Therefore, the non-operation period Tb1 can be shortened more effectively.

Since the value P1[0] is smaller than the reference value PH1, the measured value Pm1 decreases with the passage of time after the time point t11, which is already lower than the reference value PH1.

The pressure setting unit 12 changes the rate of decrease of the pressure instruction value P1* during the valve control period Ta1 of the on-off valve 71 so that the closing speed of the on-off valve 71 changes in the closing period Tc1. Here, consider dividing the blocking period Tc1 into two front periods T1 and a rear period T2. The time point t12 shows the boundary between the pre-period T1 and the post-period T2, and is the time point between the time points t11 and t13. The latter period T2 is a period later than the former period T1, and the length of the latter period T2 is set in advance, for example.

For example, the pressure setting unit 12 changes the pressure instruction value P1* during the blocking period Tc1 so that the average of the decreasing speed of the pressure instruction value P1* becomes higher during the non-operating period Tb1 and the front period T1 than the latter period T2. . More specifically, in the example of FIG. 6, the pressure setting unit 12 maintains the pressure instruction value P1* at the value P1[0] during the previous period T1 from the time point t11 to the time point t12, and at the time point t12 In the latter period T2 until the time point t13, the pressure instruction value P1* is reduced from the value P1[0] with the passage of time. That is, the pressure setting unit 12 sets the average of the decreasing speed {=(P[0]-PL1/T2)} in the post-period T2 of the pressure instruction value P1* to be higher than that in the non-operating period Tb1 and the pre-period T1 The average reduction speed of the pressure indication value P1*{=(PH1-P[0]/T1)} is still low. As a result, the measured value Pm1 gradually decreases in the latter period T2 than in the former period T1. The decreasing speed of the pressure instruction value P1* in the latter period T2 is set so that the state of the nozzle tip becomes good when the ejection is stopped.

FIG. 7 is a flowchart showing a more specific example of the above-mentioned operation of the pressure setting unit 12, and FIG. 8 is a flowchart showing a more specific example of the pressure indication value P1* and the measured value Pm1 in the post period T2 chart. As illustrated in FIG. 8, here, the pressure setting unit 12 gradually decreases the pressure instruction value P1* in the latter period T2. In the example of FIG. 8, the pressure setting unit 12 decreases the pressure instruction value P1* in five stages from the value P1[0] to the value P1[5]. Here, the value P1[1] to the value P[4] are the values when the area from the value P1[0] to the value P1[5] is equally divided into five, respectively. That is, the differences between the values P1[0] to P[5] are equal to each other. In addition, the value P1[4] is a value higher than the reference value PL1, and the value P1[5] is a value below the reference value PL1 (for example, zero). In addition, the value P1[5] can also be a value close to zero, For example, the value P1[5] may also be about 0.05 MPa.

Referring to Fig. 7, first, in step S1, the pressure setting unit 12 updates the pressure instruction value P1* from a value higher than the reference value PH1 to a value P1[0] (refer to the time point t10 in Fig. 6). As the pressure indication value P1* is updated, the measured value Pm1 becomes higher than the pressure indication value P1*(=P1[0]), so it will decrease with the passage of time. Next, in step S2, the pressure setting unit 12 updates the measured value Pm1 of the supply pressure of the gas H1. More specifically, the pressure setting unit 12 overwrites the measurement value Pm1 input from the pressure sensor 746 to the storage medium. Next, in step S3, the pressure setting unit 12 determines whether or not the updated measurement value Pm1 is the pressure instruction value P1* (=value P1[0]) or less. When the measured value Pm1 is higher than the pressure instruction value P1*, the pressure setting unit 12 executes step S2 again when it is determined that the measured value Pm1 does not match the pressure instruction value P1*. On the other hand, when the measured value Pm1 is less than or equal to the pressure instruction value P1*, the pressure setting unit 12 determines that the measured value Pm1 substantially matches the pressure instruction value P1*, and initializes the timer value to zero in step S4. The control unit 130 has a timing circuit, and the timing value is output by the timing circuit.

Next, in step S5, the pressure setting unit 12 determines whether the timer value is equal to or greater than the time Δt1. The time Δt1 is set in advance, for example. When the counted value is less than the time Δt1, the pressure setting unit 12 executes step S5 again. That is, the pressure instruction value P1* is maintained at the value P1[0] during the period from the time point when the measurement value Pm1 is very close to the pressure instruction value P1* until the time Δt1 elapses. Thereby, in the period until the elapsed time Δt1, the measured value Pm1 is substantially equal to the pressure instruction value P1*, and becomes substantially constant regardless of the elapse of time (see FIG. 8).

On the other hand, when the timer value is the time Δt1 or more, the pressure setting unit 12 initializes the value i to 1 in step S6, and updates the pressure instruction value P1* to the value P1[i] in step S7. The value P1[i] is a value lower than the value P1[i-1]. With the update of the pressure indication value P1*, since the measurement value Pm1 becomes higher than the pressure indication value P1* again, the measurement value Pm1 again decreases with the passage of time (refer to FIG. 8).

Next, in step S8, the pressure setting unit 12 determines whether the value i is less than n (here, 5). When the value i is n or more, the pressure setting unit 12 ends the operation. That is, when the pressure indication value P1* is updated to the value P1[n] (here, P1[5]), since the pressure indication value P1* does not need to be updated further, the operation ends.

On the other hand, when the value i is less than n, since the pressure instruction value P1* has not reached the value P1[n], the pressure setting unit 12 updates the measured value Pm1 in step S9, and determines the measured value Pm1 in step S10 Is the pressure indication value P1* (=value P1[i]) or less? When the measured value Pm1 is higher than the pressure instruction value P1*, the pressure setting unit 12 determines that the measured value Pm1 has not yet coincided with the pressure instruction value P1*, and performs step S9 again. When the measured value Pm1 is less than or equal to the pressure instruction value P1*, the pressure setting unit 12 determines that the measured value Pm1 substantially matches the pressure instruction value P1*, and initializes the timer value to zero in step S11.

Next, in step S12, the pressure setting unit 12 determines whether the timer value is equal to or greater than the time Δt2. The time Δt2 is preset, for example, and may be the same as the time Δt1 or different from the time Δt1. When the counted value is less than the time Δt2, the pressure setting unit 12 executes step S12 again. That is, the pressure instruction value P1* is maintained at the value P1[i] from the time point when the measurement value Pm1 approximately matches the pressure instruction value P1* until the time Δt2 has elapsed. Thereby, in the period until the elapsed time Δt2, the measured value Pm1 becomes substantially constant regardless of the elapse of time (see FIG. 8).

When the count value is the time Δt2 or more, the pressure setting unit 12 increments the value i in step S13, and then executes step S7. Thereby, as the time Δt2 elapses, the pressure indication value P1* is updated to the next value P1[i]. That is, the pressure instruction value P1* is updated every time the time Δt2 elapses from a point in time when the measured value Pm1 approximately matches the pressure instruction value P1* (=P[i]) (refer to FIG. 8). In other words, since the pressure instruction value P1* is constant after the measured value Pm1 is very close to the pressure instruction value P1* until the time Δt2 elapses, the measured value Pm1 is maintained substantially constant.

As mentioned above, due to the presence of the pressure indication value P1* in the latter period T2, it is not roughly consistent with the measured value. During the period (time △t1, time △t2) during which the magnitude Pm1 is consistent and has not been updated, the measured value Pm1 becomes approximately constant during this period; in contrast, since there is no such period in the previous period T1, the measurement The value Pm1 continuously decreases with the passage of time (see also FIG. 6). Therefore, the average rate of decrease of the measured value Pm1 in the previous period T1 is higher than that in the latter period T2. In other words, the average value of the closing speed of the on-off valve 71 in the previous period T1 is higher than that in the latter period T2.

The closing speed of the on-off valve 71 in the latter period T2 and the rate of decrease of the pressure instruction value P1* in the latter period T2 are set so that the nozzle tip state becomes good. Here, as an example, the rate of decrease of the pressure instruction value P1* in the post period T2 is evaluated by the absolute value of the inclination of the virtual line A1 connecting the protruding apexes of the step waveform of the pressure instruction value P1*. The decrease speed β 1 of the pressure instruction value P1* in the subsequent period T2 can be expressed by the following equation.

Equation (1) β 1=P1[0]/(n．△t2)

When the equation (1) is changed, the time Δt2 can be expressed by the following equation.

Equation (2) △t2=P1[0]/(n．β 1)

Since the length of the post-period T2, the value P1[0], the value n, and the reduced speed β 1 are set by simulations or experiments in such a way that the state of the nozzle tip at the time of stopping ejection becomes good, for example, it can be set according to the formula (2 ) To determine the time △t2.

As described above, it is easy to control the closing speed of the on-off valve 71 in the subsequent period T2 in such a way that the state of the nozzle tip when the spray is stopped becomes good, and it is not easy to control the nozzle tip when the spray is stopped. The blocking speed in T1 during the period before the state affects is controlled to be higher. Thereby, the ejection of the processing liquid L1 can be appropriately stopped (that is, the nozzle tip state when the ejection is stopped is set well), and the lock period Tc1 can be shortened. That is, the on-off valve 71 can be closed with higher responsiveness.

In addition, in the above example, the pressure instruction value P1* is updated stepwise during the lock period Tc1, thereby changing the lock speed during the lock period Tc1. In this way, the locking speed can be easily controlled.

In addition, in the above example, the number of times of updating the pressure instruction value P1* in the latter period T2 is more than the number of times of updating the pressure instruction value P1* in the preceding period T1. Thereby, in the period T2 after the nozzle tip state at the time of stopping ejection is likely to be affected, the rate of decrease in the supply pressure of the gas H1 and even the closing rate of the on-off valve 71 can be more finely controlled. Thereby, since the closing speed in the subsequent period T2 can be controlled to a desired speed, it is easy to set the nozzle tip state well.

(3-2-1) Change in the decreasing speed of the pressure indicating value P1*

(3-2-1-1) value P(i)

In the examples of FIGS. 6 and 8, although the rate of decrease of the pressure instruction value P1* is constant in the latter period T2 of the lock period Tc1, it is not limited to this. FIG. 9 is a graph showing an example of the pressure indication value P1* and the measured value Pm1 in the post period T2. In the example of FIG. 9, the difference between the value P1[0] and the value P[5] is not constant. Specifically, the first difference between the value P1[0] to the value P[2] is constant with each other, and the second difference between the value P1[2] to the value P1[5] is constant with each other, but the first difference Set to be larger than the second difference. Thereby, the decrease speed β 1 of the pressure instruction value P1* becomes a low value β 12 after obtaining a high value β 11 in the initial stage of the subsequent period T2. That is, in the latter period T2, the rate of decrease of the pressure instruction value P1* can be changed. Decrease speed β 1 is expressed by the following two formulas.

Equation (3) β 11=(P1[0]-P1[2])/(2．△t2)

Equation (4) β 12=(P1[2]-P1[5])/(3．△t2)

(3-2-1-2) Time△t2

It is also possible to appropriately change the time Δt2, thereby changing the reduction speed β1. Figure 10 is used to show The flowchart of an example of the operation of the pressure setting unit 12 is a graph showing an example of the pressure instruction value P1* and the measured value Pm1 in the subsequent period T2. Compared with FIG. 7, in the flowchart of FIG. 10, steps S121 to S123 are provided instead of step S12. Step S121 is executed after step S11. In step S121, the pressure setting unit 12 determines whether or not the value i is n1 (lower than n, here, 2) or less. When the value i is equal to or less than n1, in step S122, the pressure setting unit 12 determines whether or not the timer value is equal to or greater than the time Δt21. The time Δt21 is set in advance, for example. When the counted value is less than the time Δt21, the pressure setting unit 12 executes step S122 again. When the count value is equal to or greater than the time Δt21, the pressure setting unit 12 sequentially executes step S13 and step S7. That is, when the value i is equal to or less than n1, the pressure instruction value P1* is updated when the time Δt21 has elapsed from the time point when the measured value Pm1 approximately matches the pressure instruction value P1* (step S13, step S7).

In the example of FIG. 11, at the time point when the time Δt21 has elapsed since the measured value Pm1 approximately coincides with the pressure indication value P1*(=P1[1]), the pressure indication value P1* is updated to the value P1 [1]; At the time point when the measured value Pm1 approximately coincides with the updated pressure indication value P1*(=P[2]), the pressure indication value P1* is updated to the value P1 [3].

When the value i is higher than n1 in step S121, the pressure setting unit 12 determines whether the timer value is equal to or greater than the time Δt22 in step S123. The time Δt22 is different from the time Δt21. For example, it is set to a value longer than the time Δt21. When the counted value is less than the time Δt22, the pressure setting unit 12 executes step S123 again. When the count value is equal to or greater than the time Δt22, the pressure setting unit 12 sequentially executes step S13 and step S7. That is, when the value i is higher than n1, the pressure instruction value P1* is updated when the time Δt22 has elapsed from the time point when the measured value Pm1 approximately coincides with the pressure instruction value P1* (step S13, step S7).

In the example of FIG. 11, at the time point when the time Δt22 elapses from the time point when the measured value Pm1 approximately coincides with the pressure indication value P1*(=P1[3]), the pressure indication value P1* is updated to the value P1 [4]; At the point in time when the measured value Pm1 is roughly consistent with the updated pressure indication value P1*(=P[4]) At the time point after the elapsed time Δt22, the pressure indication value P1* is updated to the value P1[5].

Thereby, the decreasing speed β 1 of the pressure instruction value P1* takes a high value β 13 and then takes a low value β 14. That is, in the latter period T2, the rate of decrease of the pressure instruction value P1* can be changed. Decrease speed β 1 (β 13, β 14) is expressed by the following two formulas.

Equation (5) β 13=(P1[0]-P1[2])/(2．△t21)

Equation (6) β 14=(P1[2]-P1[5])/(3．△t22)

In the example of FIG. 9 and FIG. 11, the decreasing speed β 1 of the pressure instruction value P1* in the subsequent period T2 decreases as the time elapses. Thereby, the reduction speed β 1 is gradually reduced during the lock-up period Tc1. Therefore, a sudden change in the closing speed of the on-off valve 71 can be avoided. Thereby, it is possible to reduce the possibility of stinginess in the treatment liquid L1.

In addition, in the example of FIG. 9 and FIG. 11, although the reduction speed β1 is changed only once in the subsequent period T2, it may be changed more finely.

(3-2-2) PID (Proportional-Integral-Derivative; proportional-integral-derivative) control

(3-2-2-1) gain

In the above example, the pressure indication value P1* is gradually decreased in the lock period Tc1, thereby changing the rate of decrease of the measured value Pm1 and even the closing rate of the on-off valve 71. However, it is not limited to this. For example, in the case of P (proportional; proportional) control, PI (Proportional-Integral) control, or PID (proportional-integral-derivative) control feedback control, the decrease speed of the measured value Pm1 depends on the The gains used in this feedback control (proportional gain, integral gain, and derivative gain). Therefore, the gain can also be appropriately set to adjust the decrease speed of the measured value Pm1 and even the closing speed of the on-off valve 71.

FIG. 12 is a functional block diagram for schematically showing an example of the internal structure of the control unit 130. For example, the control signal generation unit 13 has a subtractor 131, a PID control unit 132, and a comparison unit 133. The pressure instruction value P1* from the pressure setting unit 12 and the measurement value Pm1 from the pressure sensor 746 are input to the subtractor 131. The subtractor 131 calculates the difference ΔP (=Pm1-P*) between the pressure instruction value P1* and the measured value Pm1, and outputs the difference ΔP to the PID control unit 132.

The PID control unit 132 performs P control, PI control, or PID control on the difference ΔP, generates an energy rate instruction value D*, and outputs the energy rate instruction value D* to the comparison unit 133. The energy rate indicator value D* is a target value of the energy rate for the opening and closing of the solenoid valves 741 and 742. In addition, since the supply pressure of the gas H1 used to close the on-off valve 71 when the ejection is stopped decreases, the energy rate of the solenoid valve 741 can also be constantly set to zero during the closing operation. Here, as an example, the energy rate indicator value D* is used as an indicator value of the energy rate of the solenoid valve 742. Here, the energy rate refers to, for example, the ratio of the period during which the solenoid valve 742 is opened in one cycle. The higher the energy rate of the solenoid valve 742, the higher the rate of decrease of the supply pressure of the gas H1. That is, the energy rate indicator value D* can be said to be an indicator value corresponding to the supply pressure of the gas H1.

The comparison unit 133 compares the energy rate indication value D* with a carrier wave (for example, a triangular wave), generates a control signal for the solenoid valve 742 based on the comparison, and outputs the control signal to the control board 140. The control board 140 controls the solenoid valve 742 according to the control signal.

With this control, the measured value Pm1 is close to the pressure indicating value P1*. FIG. 13 is a graph for schematically showing an example of the pressure indicating value P1* and the measured value Pm1. In the example of FIG. 13, the pressure setting unit 12 updates the pressure instruction value P1* to the value P1[0] at the time point t10. As the pressure indication value P1* decreases, the measured value Pm1 decreases with the passage of time after the time point t10. Specifically, the pressure measurement value Pm1 decreases at a higher rate of decrease when it leaves the pressure indicating value P1*, and decreases at a lower rate of decrease as it approaches the pressure indicating value P1*. The measured value Pm1 is gradually approaching the pressure indication value P1*.

Then, the difference between the measured value Pm1 and the pressure indication value P1*(=P1[0]) becomes At the time t12 which is smaller than the predetermined value, the pressure setting unit 12 updates the pressure instruction value P1* from the value P1[0] to the value P1[5] (for example, zero). With this update, since the measured value Pm1 becomes higher than the pressure indication value P1*(=P[5]) at the time point t12, the measured value Pm1 decreases again at a high rate of decrease, but as it approaches the pressure The indicating value P1* decreases the speed of decrease.

The decrease speed of the measured value Pm1 depends on the gain (proportional gain, integral gain, and derivative gain) used in the PID control unit 132. For example, when the proportional gain is set to be larger, the measured value Pm1 decreases at a higher rate of decrease, especially when it departs from the pressure indicating value P1*. Therefore, the rate of decrease of the measured value Pm1 can also be controlled based on these gains.

The various gains in the PID control unit 132 are set in such a way that the nozzle tip state at the time of stopping ejection becomes good, and the average rate of decrease of the measured value Pm1 in the preceding period T1 becomes higher than the latter period T2.

In addition, in the example of FIG. 13, although the pressure indication value P1* is temporarily updated to the value P1[0] at the time point t10, and the value P1[0] is updated to the value P1[5] at the time point t12 (for example, Is zero), but it can also be updated to the value P1[5] at time t10. However, as long as the pressure indication value P1* is gradually decreased, the rate of decrease of the measured value Pm1 can be controlled more finely. A more detailed example will be described later.

(3-2-2-2) Pressure indication value

It is also possible to use the above-mentioned P control, PI control, or PID control to gradually reduce the pressure indication value P1*, thereby more finely controlling the rate of decrease of the measured value Pm1 in the blocking period Tc1. FIG. 14 is a diagram for schematically showing an example of the pressure indication value P1* and the measurement value Pm1 in the post period T2. In the example described with reference to FIGS. 7 and 8, the pressure instruction value P1* is updated when the time Δt1 or the time Δt2 elapses from the time point when the measured value Pm1 becomes the pressure instruction value P1* or less. However, in the example of FIG. 14, since the measured value Pm1 gradually approaches the pressure indicating value P1* by feedback control, it is difficult for the measured value Pm1 to become the pressure indicating value P1* or less. That is, in the determination of step S13 and step S10 in FIG. 7, it is difficult to detect the start timing of time Δt1 and Δt2.

Therefore, in the example of FIG. 14, the pressure setting unit 12 is after the time Δt1 has elapsed from the time point t12 when the measured value Pm1 becomes the pressure instruction value P1*(=P1[0]) and the predetermined value p1 or less. Update the pressure indication value P1* to the value P1[1]. Similarly, the pressure setting unit 12 changes the time Δt2 after the measured value Pm1 becomes the pressure instruction value P1*(=P1[i]: i=1 to 5) and the predetermined value p2 after the time Δt2 has elapsed. The pressure indication value P1* is updated to the value P1[i+1].

That is, an example of the operation of the pressure setting unit 12 is the same as the flowchart of FIG. 7 except for step S3 and step S10. That is, in step S3, the pressure setting unit 12 determines whether the measured value Pm1 is the sum of the pressure instruction value P1*(=P1[0]) and the predetermined value p1 or less; in step S10, the pressure setting unit 12 determines Whether the measured value Pm1 is the sum of the pressure indication value P1*(=P1[i]) and the predetermined value p2 or less. In addition, the predetermined value p1 may be the same as the predetermined value p2 or may be different from the predetermined value p2.

In addition, in all of the above-mentioned graphs, the rate of decrease of the measured value Pm1 in the lock-up period Tc1 changes so as to gradually decrease. However, it is not limited to this. As long as the condition that the state of the nozzle tip at the time of stopping ejection becomes good is satisfied, the rate of decrease of the measured value Pm1 may be changed arbitrarily during the lock period Tc1. For example, as long as the time series change of the measurement value Pm1 in the subsequent period T2 is more suitable for setting the waveform of the nozzle tip state, the pressure instruction value P1* or various gains may be appropriately set. For example, the pressure indication value P1* may be set in such a way that the decreasing speed of the measured value Pm1 in the subsequent period T2 gradually increases.

In addition, in the case where it is not necessary to shorten the lock-up period Tc1, the lock-up speed in the front period T1 may be set to be lower than the latter period T2. In short, it is also possible to independently set the blocking speed in the front period T1 and the blocking speed in the rear period T2. Thereby, it is possible to control the closing speed in the subsequent period T2 so that the state of the nozzle tip at the time of stopping ejection becomes good, and to independently adjust the closing period Tc1.

(3-2-3) Tb1 during non-operation

Next, the rate of decrease of the measured value Pm1 in the non-operation period Tb1 will be described. The non-operation period Tb1 is the period after the supply pressure of the gas H1 starts to decrease until the valve body 711 starts to move. that is, The non-operation period Tb1 is a period during which the valve body 711 of the on-off valve 71 has not moved. Therefore, the non-operation period Tb1 is preferably short. This is because the valve control period Ta1 can be shortened and the responsiveness of the on-off valve 71 can be improved.

Therefore, the control unit 130 may also control the solenoid so that the average of the decrease speed of the measured value Pm1 in the non-operation period Tb1 becomes more than the average of the decrease speed of the measured value Pm1 in the lock-up period Tc1 (more specifically, the previous period T1). Valves 741, 742.

In the example of FIG. 6, the pressure instruction value P1* is constant in the value P[0] during the non-operation period Tb1 and the preceding period T1, and gradually decreases in the latter period T2. In the example of FIG. 6, the decrease speed of the measured value Pm1 is the same in the non-operation period Tb1 and the previous period T1, and is higher in the subsequent period T2. Thereby, the non-operation period Tb1 can be shortened compared with the case where the rate of decrease in the non-operation period Tb1 of the measured value Pm1 is lower than the previous period T1. In addition, although the pressure instruction value P1* may be gradually decreased in the preceding period T1, it is only necessary to set the decrease speed to be lower than the decrease speed in the non-operation period Tb1 and higher than the latter period T2.

In the example of FIG. 13, the pressure instruction value P1* is constant at the value P1[0] in the non-operation period Tb1 and the preceding period T1, and takes a lower value P1[5] in the latter period T2. In the example of FIG. 14, due to the P control, PI control, or PID control, the measured value Pm1 is farther from the pressure instruction value P1*. The average of the decrease speed in the non-operation period Tb1 is closer to the pressure instruction than the measured value Pm1 The value P1* has a higher average rate of decrease in the previous period T1, and is higher than the average rate of decrease in the subsequent period T2. Thereby, the non-operation period Tb1 can be shortened compared with the case where the rate of decrease in the non-operation period Tb1 of the measured value Pm1 is lower than the previous period T1.

By shortening the non-operation period Tb1, the valve control period Ta1 can be shortened. That is, the responsiveness of the on-off valve 71 can be improved. In addition, at the point where the responsiveness of the on-off valve 71 is improved, although the pre-period T1 can be shortened, the increase in the closing speed in the pre-period T1 may cause the processing liquid L1 to become stingy. In contrast, since the non-operating period Tb1 is a period during which the valve body 711 is not moving, even if the rate of decrease of the measured value Pm1 in the non-operating period Tb1 is increased, the processing liquid L1 does not become stingy. because Therefore, it is desirable to shorten the non-operation period Tb1 preferentially over the shortening of the previous period T1.

In addition, the control signal generating unit 13 can also generate control signals for the solenoid valves 741 and 742 by constantly closing the solenoid valve 741 for air supply and opening the solenoid valve 742 for exhaust constantly during the non-operation period Tb1. . Thereby, in the non-operation period Tb1, the supply pressure of the gas H1 is reduced at the maximum reduction rate. Therefore, the non-operation period Tb1 can be shortened the most.

(3-3) Action speed of suction valve 72

The operating speed of the suction valve 72 when the discharge is stopped also affects the state of the nozzle tip when the discharge is stopped. The operating speed referred to here corresponds to the deformation speed of the valve body 721 of the suction valve 72. When the operating speed of the suction valve 72 is too high, the treatment liquid L1 will fall as a drop from the tip 252 of the nozzle 251 when the ejection is stopped (see also FIGS. 5 and 26). That is, the state of the tip of the nozzle becomes a poor state. Therefore, here, it is desirable to set the operating speed of the suction valve 72 when the discharge is stopped to an appropriate value in the operating period Tc2. Here, since the suction valve 72 is a gas-actuated valve, the control unit 130 controls the rate of decrease of the supply pressure of the gas H2 supplied to the suction valve 72, thereby controlling the operating speed. Hereinafter, it will be explained more specifically.

The pressure setting unit 12 sets a target value (hereinafter referred to as a pressure instruction value) P2* for the supply pressure of the gas H2 supplied to the suction valve 72, and outputs the pressure instruction value P2* to the control signal generation unit 13. The control signal generating unit 13 generates control signals for the solenoid valves 751 and 752 according to the pressure instruction value P2* in such a way that the supply pressure of the gas H2 approaches the pressure instruction value P2*, and outputs the control signal to the control board 140. The control board 140 controls the solenoid valves 751 and 752 according to the control signal.

As described above, the valve body 721 (FIG. 4) of the suction valve 72 keeps the volume of the flow path space 72b2 small when the supply pressure of the gas H2 is high, and reduces the supply pressure of the gas H2 to make the flow The volume of the path space 72b2 increases, so that the suck-in operation is performed.

Therefore, the pressure setting unit 12 gradually decreases the pressure instruction value P2* from a value higher than the reference value PH2 to a value lower than the reference value PL2 during the suction operation. Figure 15 is used to show A graph showing an example of the pressure indication value P2* and the measured value Pm2 of the supply pressure of the gas H2. Here, the period from the time point t20 when the pressure instruction value P2* starts to decrease to the time point t22 when the measured value Pm2 is lower than the reference value PL2 is called the valve control period Ta2, and it starts from the time point t20 to the pressure The period from time t21 when the instruction value P2* is lower than the reference value PH2 is referred to as a non-operating period Tb2, and the period from time t21 to time t22 is referred to as an operating period Tc2.

In the example of FIG. 15, the pressure indication value P2* and the measurement value Pm2 are initially higher than the reference value PH2 and approximately the same. The reason is that the solenoid valves 751 and 752 are controlled in such a way that the pressure indication value P2* is initially higher than the reference value PH2 and the measured value Pm2 is close to the pressure indication value P2*. Since the measured value Pm2 is higher than the reference value PH2, the suction valve 72 initially maintains the volume of the flow path space 72b2 at a small value. In addition, the on-off valve 71 is opened initially, and the processing liquid L1 is ejected from the nozzle 251 toward the upper surface of the substrate W.

The pressure setting unit 12 updates the pressure instruction value P2* to the value P2[0] in accordance with the closing of the on-off valve 71 (refer to the time point t20). The value P2[0] is higher than the reference value PL2 and is a value less than the reference value PH2. Here, the value P2[0] is equal to the reference value PH2. When the pressure indication value P2* is updated to the value P2[0], the solenoid valves 751 and 752 are controlled so that the supply pressure of the gas H2 approaches the value P2[0], so the supply pressure of the gas H2 is over time. And reduce. Therefore, in FIG. 15, the measured value Pm2 decreases with the passage of time after the time point t20. Next, when the measured value Pm2 is lower than the reference value PH2, the valve body 721 of the suction valve 72 starts to deform. That is, the suction valve 72 starts the suction operation.

The non-operation period Tb2 is a period after the pressure instruction value P2* is lowered until the valve body 721 of the suction valve 72 starts to deform, and the non-operation period Tb2 is desirably short. In the example of FIG. 15, the pressure indication value P2* is not gradually reduced to the value P2[0] with the passage of time in the non-operation period Tb2, but at the start time point of the non-operation period Tb2 (time At point t20), it decreases to the value P2[0]. This is suitable for shortening the non-operation period Tb1.

The pressure setting part 12 is approximately equal to the measured value Pm2 and the pressure indication value P2*(=P2[0]) At the coincident time point t21, the pressure indicating value P2* is gradually reduced from the value P2[0] as time passes. That is, the pressure setting unit 12 sets the average of the decreasing speed {=(P2[0]-PL2)/Tc2} during the operation period Tc2 of the pressure instruction value P2* to be higher than the pressure instruction value P2 in the non-operation period Tb2 The average reduction rate of *{=(PH2-P2[0]/Tb2)} is still low. Thereby, the supply pressure of the gas H2 (measured value Pm2) decreases more slowly in the operating period Tc2 than in the non-operating period Tb2. The decrease speed of the pressure instruction value P2* in the operation period Tc2 is set so that the state of the nozzle tip becomes good when the ejection is stopped. The rate of decrease is set by simulation or experiment, for example.

An example of the specificity of the operation of the pressure setting unit 12 is the same as the flowchart of FIG. 7. Specifically, in FIG. 7, it is sufficient to replace P1*, Pm1, P1[0], and P1[i] with P2*, Pm2, P2[0], and P2[i], respectively. Therefore, repeated descriptions are omitted here.

Thereby, since the decrease speed of the measured value Pm2 in the non-operating period Tb2 can be set higher than the operating period Tc2, the nozzle tip state when the ejection is stopped can be set well, and the valve control period Ta2 can be shortened. In other words, the responsiveness of the suction valve 72 can be improved.

(3-3-1) Changes in operating speed during the operating period

(3-3-1-1) Pressure indication value

In FIG. 15, although the decreasing speed of the pressure instruction value P2* in the operation period Tc2 is approximately constant, it is not limited to this. Fig. 16 is a diagram for showing an example of the pressure indication value P2* and the measurement value Pm2. In the example of FIG. 16, the operation period Tc2 is divided into two front period T21 and a rear period T22. The pressure indicator value P2* in the front period T21 decreases at a different speed from the decrease speed in the rear period T22. high. Such a change in the reduction speed is achieved by changing at least one of the mutual difference of the value P2[i] and the time Δt2 as described with reference to FIGS. 8 and 9.

(3-3-1-2) PID control part

As with the on-off valve 71, the control unit 130 controls the suction valve 72 using feedback control of P control, PI control, or PID control. Figure 17 shows an example of the pressure indication value P2* and the measured value Pm2 之图. In Fig. 17, the pressure setting unit 12 updates the pressure indication value P2* to the value P2[0] at the time point t20, at the time when the measured value Pm2 roughly coincides with the pressure indication value P2*(=P2[0]) At point t21, the pressure instruction value P2* is updated to a value below the reference value PL1 (here, it is zero).

The measured value Pm2 is decreased at a rate of decrease depending on the various gains used in the feedback control. In the example of FIG. 17, the rate of decrease of the measured value Pm2 is that the closer the measured value Pm2 is to the pressure indicating value P2*, the lower it becomes. The various gains used in the feedback control are set in such a way that the state of the nozzle tip at the time of stopping ejection becomes good.

(4) Drive mechanism and valve

(4-1) Needle valve

In the above example, the drive mechanism 74 is provided with solenoid valves 741 and 742, and the drive mechanism 75 is provided with solenoid valves 751 and 752, but it is not limited to this. For example, the drive mechanism 74 may be provided with a needle valve for air supply and a needle valve for exhaust gas instead of the solenoid valves 741 and 742. The needle valve for air supply is provided in the middle of the path of the pipe 743, and the exhaust needle valve The valve system is provided in the middle of the path of the pipe 744. Each needle valve is driven by a motor, and the opening degree of the needle valve is variable. For example, the more the opening degree of the pipe 744 is increased by the needle valve for exhaust, the lower the speed of the supply pressure of the gas H1 becomes higher. Therefore, the drive mechanism 74 changes the opening degree of the needle valve for exhaust during the lock period Tc1, thereby changing the rate of decrease of the supply pressure of the gas H1 as described above. The same is true for the drive mechanism 75.

(4-2) Electric valve

In the above example, the on-off valve 71 and the suction valve 72 are gas-actuated valves. However, it is not limited to this. The on-off valve 71 and the suction valve 72 may also be electric valves. FIG. 18 is a diagram schematically showing an example of the configuration of the substrate processing unit 1A as another example of the substrate processing unit 1.

The substrate processing unit (that is, the processing liquid ejection device) 1A has the same configuration as the substrate processing unit 1 except that the processing liquid supply unit 7A is provided instead of the processing liquid supply unit 7 of the substrate processing unit 1. Like the substrate processing unit 1, the substrate processing unit 1A is capable of ejecting and processing the substrate W Liquid L1 processes the substrate W piece by piece. The substrate processing apparatus 100 can process a plurality of substrates W in parallel by a plurality of substrate processing units 1A.

The processing liquid supply section 7A of the substrate processing unit 1A is provided with an on-off valve (i.e., electric valve) 71A, a suction valve (i.e., electric valve) 72A, and drive mechanisms 74A, 75A instead of the on-off valve of the processing liquid supply section 7 71. Except for the suction valve 72 and the drive mechanisms 74 and 75, it has the same configuration as the processing liquid supply unit 7.

The on-off valve 71A includes a valve body 710 and a motor (that is, an electric motor) 717, and the motor 717 drives the opening and closing mechanism of the valve body 710, thereby opening and closing the on-off valve 71A. The valve body 710 is provided in the middle of the path of the pipe 73. The valve body 710 is provided with, for example, a rod-shaped body (valve body) not shown in the figure. The rod-shaped system can open and close the valve body 710 by advancing and retreating in a direction transverse to the inside of the pipe 73, that is, the rod-shaped system The system can open and close the flow path of the pipe 73 by advancing and retreating in a direction transverse to the inside of the pipe 73. The rod-shaped system is connected to a ball screw mechanism not shown, for example, and the ball screw mechanism is connected to the rotation shaft of the motor 717. When the motor 717 rotates, the rod-shaped system advances and retreats in a direction corresponding to the rotation speed at a speed corresponding to the rotation speed of the motor 717. Thereby, the opening degree and the opening and closing speed of the valve body 710 are arbitrarily adjusted. The control unit 130 supplies a control signal corresponding to the target opening and closing speed to the control board 141. The control board 141 has a driving circuit for driving the motor 717, and supplies the driving current corresponding to the control signal to the motor 717. The opening and closing valve 71A performs opening and closing operations at a speed corresponding to the number of rotations (rotation speed) of the motor 717. In other words, the on-off valve 71A is connected to the drive current supplied by the control board 141 (when the motor 717 is, for example, a DC (direct current) motor, it is the current value of the drive current; when the motor 717 is, for example, a stepping motor When motor) is the frequency of the pulse wave of the driving current) the opening and closing are performed at the corresponding speed. That is, the drive mechanism 74A can be said to be a motor 717 provided with a control board 141 and an on-off valve 71A.

Even in this substrate processing unit 1A, similar to the on-off valve 71, the closing speed of the on-off valve 71A is changed during the closing period. However, since the closing speed of the on-off valve 71A is taken Depending on the rotation speed of the motor 717, the control unit 130 changes the rotation speed of the motor 717 during the lock period. For example, the control unit 130 sets the instruction value for the rotation speed in the following manner. That is, the instruction value of the rotation speed in the subsequent period is set so that the nozzle tip state at the time of stopping ejection becomes good, and the average of the instruction value of the rotation speed in the previous period is set so that it becomes higher than the subsequent period.

The suction valve 72A is provided with a valve body 720 and a motor (that is, an electric motor) 727, and the motor 727 is a valve mechanism that drives the valve body 720, thereby controlling the suction valve 72A. The valve body 720 is provided in the middle of the path of the pipe 73. For example, a valve body is provided in the valve body 720, and the valve system is formed with a flow path space that functions as a part of the flow path inside the pipe 73, and the valve system can change the volume of the flow path space. The valve system is connected to a ball screw mechanism not shown, for example, and the ball screw mechanism is connected to the rotating shaft of the motor 727. When the motor 727 rotates, the valve system deforms or moves at a speed corresponding to the rotation speed of the motor 727 and changes the volume of the flow path space. The operating speed of the suction valve 72A is arbitrarily adjusted. The control unit 130 supplies the control signal corresponding to the target movement speed to the control board 142. The control board 142 has a driving circuit for driving the motor 727, and supplies the driving current corresponding to the control signal to the motor 727. The suction valve 72A performs a suction operation at a speed corresponding to the number of rotations (rotation speed) of the motor 727. In other words, the suction valve 72A is based on the driving current supplied by the control board 142 (when the motor 727 is a DC motor, for example, it is the current value of the driving current; when the motor 727 is a stepping motor, it is the pulse of the driving current. The frequency of the wave) corresponding to the speed of the suction action. That is, the drive mechanism 75A can be said to be a motor 727 provided with a control board 142 and a suction valve 72A.

Even in this substrate processing unit 1A, the operation speed of the suction valve 72A is controlled in the same manner as the suction valve 72. However, since the operating speed of the suction valve 72A depends on the rotation speed of the motor 727, the control unit 130 sets the rotation speed of the motor 727. For example, the control unit 130 sets the instruction value for the rotation speed in the following manner. That is, in the state of the nozzle tip when the spray is stopped It becomes a good way to set the instruction value of the rotation speed during the operation period.

(4-3) The form of the valve

In the above example, the on-off valve 71 is a normally closed valve. However, it may also be a normally open type gas actuated valve. In this case, the increase speed of the supply pressure of the gas H1 is controlled during the lock period Tc1, thereby controlling the lock speed. Similarly, the suction valve 72 may also be a gas-actuated valve of the following type: in the state where the gas H2 is exhausted, the volume of the flow path space 72b2 is maintained at a small value, and in the state where the gas H2 has been supplied The volume of the flow path space 72b2 is increased. In this case, by controlling the increase speed of the supply pressure of the gas H2 during the operation period Tc2, the operation speed of the suction valve 72 during the suction operation can be controlled.

(5) Type of indication value

In the above example, in order to adjust the operating speed of the on-off valve 71 and the suction valve 72, the pressure instruction values P1* and P2* are set, but the energy rate instruction value D* may be set. The reason for this is as follows: the greater the energy rate of the solenoid valve 742, the higher the rate of decrease of the supply pressure of the gas H1, and the greater the energy rate of the electromagnetic valve 752, the higher the rate of decrease of the supply pressure of the gas H2. For example, the energy rate indication value D* for the solenoid valve 742 may be sequentially decreased during the lock period Tc1, thereby reducing the rate of decrease of the supply pressure of the gas H1 sequentially during the lock period Tc1. The same applies to the solenoid valve 752.

When each of the drive mechanisms 74 and 75 has a needle valve for air supply and a needle valve for exhaust gas, since the opening degree of these needle valves is controlled, the opening degree indication value can also be set. For example, by sequentially decreasing the opening degree indication value of the needle valve for exhaust of the drive mechanism 74 during the lock period Tc1, the rate of decrease in the supply pressure of the gas H1 can be sequentially decreased during the lock period Tc1. The openness indicator value can also be said to be an indicator value corresponding to the pressure of the gas H1.

(Second Embodiment)

In the second embodiment, it is desirable to use the camera to photograph the state of the nozzle tip when the ejection is stopped, and adjust the state of the nozzle tip when the ejection is stopped according to the captured image so that the state of the nozzle tip becomes good. At least one of the closing speed of the on-off valve 71 and the operating speed of the suction valve 72.

(1) Substrate processing unit

FIG. 19 is a diagram for schematically showing an example of the configuration of the substrate processing unit 1B. Compared with the first embodiment, the substrate processing unit 1B is further provided with a speed determination device (also referred to as a determination device) 300. In addition, at least the tip of the nozzle 251 has a transparent material. As the material with the transparent material, for example, PFA (tetrafluoroethylene-par fluoro alkyl vinyl ether copolymer; tetrafluoroethylene copolymer) or quartz can be used. Therefore, the processing liquid L1 of the flow path TG1 existing in the tip portion of the nozzle 251 is captured by the camera 65 described later. In addition, the processing liquid L1 supplied to the nozzle 251 is ejected from the tip 252 of the nozzle 251 to the substrate W side in the ejection direction AR1 through the flow path TG1 of the nozzle 251. Hereinafter, the area where the processing liquid L1 flows from the tip 252 of the nozzle 251 along the ejection direction AR1 is also referred to as the ejection path TG2.

The determination device 300 determines at least one of whether the closing speed of the opening and closing valve 71 is appropriate and whether the operation speed of the suction valve 72 is appropriate. Hereinafter, first, the determination of the locking speed will be explained.

(1-1) Judging device

The determination device 300 is provided with a control unit 130 (also refer to FIG. 20, more specifically, the determination unit 14 described later) and a camera (that is, an imaging unit) 65 installed in the housing 121. The camera 65 is electrically connected to the control unit 130.

(1-1-1) Camera

The camera 65 is equipped with a lens, an imaging element, and a control processing circuit (none of which is shown). The lens system images the optical image of the subject to the imaging element. The imaging element converts the optical image of the object into an electrical signal and supplies it to the control processing circuit. The control processing circuit is electrically connected to the control unit 130, and follows the control signal supplied by the control unit 130 to make the imaging element perform shooting operations, process various electrical signals supplied from the imaging element and convert it into a multi-value digital image, thereby Generate an image signal to indicate an image corresponding to the effective pixel number of the imaging element and supply it to the control unit 130.

That is, the camera 65 processes various electrical signals supplied by the imaging element and converts them into digital images, thereby generating image signals corresponding to the effective pixel number of the imaging element and outputting the image signals to the control unit 130. The control unit 130 stores the image signal (image) to, for example, the magnetic disk 161.

Specifically, when the on-off valve 71 closes the flow path and stops ejecting the treatment liquid L1 from the nozzle 251, the camera 65 follows the control of the control unit 130 to photograph the imaging target area 50 specified in the housing 121 and obtain the image G0. Hereinafter, the image G0 is also referred to as the original image G0. The imaging target area 50 includes the flow path of the tip portion of the nozzle 251 and the ejection path of the processing liquid L1. The ejection path of the processing liquid L1 is from the tip (ejection port) 252 of the nozzle 251 along the ejection direction AR1 of the processing liquid L1. Extend to the front. The camera 65 photographs from a direction different from the ejection direction AR1. In FIG. 19, the tip portion of the nozzle 251 includes an internal region 51, and the tip 252 of the nozzle 251 includes a front region 52 in the ejection path of the processing liquid L1 extending forward in the ejection direction AR1. In addition, the imaging target area 50 includes an inner area 51 and a front area 52. The lower end of the inner area 51 is located above the front end 252 of the nozzle 251, for example, the upper end of the front area 52 is substantially coincident with the front end 252 of the nozzle 251. The lower end of the inner area 51 is separated from the upper end of the front area 52.

Referring also to FIG. 5, the inner area 51 and the front area 52 are areas where the state of the nozzle tip can be visually recognized. That is, the inner area 51 and the front area 52 are areas where the change in the nozzle tip state corresponding to the closing speed of the opening and closing valve 71 can be visually recognized. Therefore, the camera 65 photographs the photographic target area 50 including the inner area 51 and the front area 52, so that the nozzle tip state corresponding to the locking speed can be included in the original image G0.

The camera 65 follows the control of the control unit 130, and after the on-off valve 71 closes the flow path and stops ejecting the processing liquid L1 from the nozzle 251, it sequentially photographs the internal area 51 and the front area 52 including the tip of the nozzle 251 in time. In the imaging target area 50, the front area 52 extends forward from the tip 252 of the nozzle 251 along the ejection direction AR1 of the processing liquid L1.

(1-1-2) Control Department

FIG. 20 is a functional block diagram for schematically showing an example of the internal structure of the control unit 130. The control unit 130 includes a determination unit 14 and an image generation unit 17 in addition to the pressure setting unit 12 and the control signal generation unit 13. Since the determination unit 14 and the image generation unit 17 perform operations based on the original image G0 captured by the camera 65, they can also be said to belong to the determination device 300.

(1-1-2-1) Judgment Department

The judging unit 14 performs predetermined judging processing based on the image of the internal area 51 of the tip of the nozzle 251 and the image of the area 52 in front of the nozzle 251 in the original image G0 of the photographic target area 50 captured by the camera 65, thereby judging the opening and closing valve 71 Which of the following distinctions is the locking speed of the opening and closing valve 71 is appropriate, or the closing speed of the opening and closing valve 71 is higher than the preset appropriate speed (that is, the target speed or the target locking speed), or the opening and closing The closing speed of the valve 71 is lower than an appropriate speed set in advance. In other words, the determination unit 14 determines the stop state of the treatment liquid L1 from the nozzle 251 (the nozzle tip state when the discharge is stopped).

The determination unit 14 includes a feature quantity calculation unit 15 and a predetermined basic determination unit 16.

The feature amount calculation unit 15 is for the first image G1 of the area A (that is, the first image area) corresponding to the inner area 51 in the original image G0 of the photographic target area 50 captured by the camera 65 and the first image G1 corresponding to the front area 52 For each image of the second image G2 in the area B (that is, the second image area), a predetermined feature amount corresponding to the area of the image of the treatment liquid L1 is calculated. As the feature quantity, for example, the sum of the pixel values in the gray scale, the sum of the brightness, the standard deviation of the pixel value in the gray scale, or the brightness of each pixel in the region of the first image G1 and the second image G2 is used. Standard deviation, etc.

The predetermined basic determination unit 16 applies a predetermined determination rule K1 to the feature amount of the first image G1 and the feature amount of the second image G2, thereby determining the distinction between the closing speed of the on-off valve 71.

For example, the following rule is adopted as the determination rule K1: when the internal area 51 is not in a liquid-tight state, it is determined that the closing speed of the on-off valve 71 is too high; when the internal area 51 is in a liquid-tight state and the treatment liquid L1 exists in the front area 52 At this time, it is determined that the closing speed of the on-off valve 71 is too low. The determination rule K1 is memorized on the disk 161, for example. In this determination, since the original image G0 reflecting the change in the nozzle tip state corresponding to the closing speed of the on-off valve 71 is used to determine whether the closing speed is appropriate, it is possible to determine whether the operating speed is appropriate with high determination accuracy.

(1-1-2-2) Image generation department

As described with reference to FIG. 5, in a case where the closing speed of the on-off valve 71 is too low, the droplet L2 is dropped from the nozzle 251 when the ejection is stopped. Since the time when the droplet L2 falls is not fixed, it is difficult to include the droplet L2 in the original image G0 in one shot. Therefore, the camera 65 continuously images for a certain period of time when the ejection is stopped, thereby attempting to image the droplet L2. Thereby, the droplet L2 can be included in any one of the original images G0 (time series images) obtained by shooting.

Although the judging unit 14 can also apply the judging rule K1 to all the original images G0 of the plurality of original images G0, here, in order to make the processing easier, an image that becomes the application target of the judgment rule K1 is generated based on the plurality of original images G0. (That is, derived image) G10.

For example, the image generation unit 17 generates a derivative image G10 based on a time series image (a plurality of original images G0), which is taken during the period after the nozzle 251 stops spraying the treatment liquid L1 until a certain time elapses. The certain period of time is, for example, three seconds. The discharge stop sequence for specifying the start sequence for the predetermined time may be, for example, a point in time when the pressure indication value P1* has fallen below the reference value PL1 or a point in time delayed from this point in time to a predetermined time. Alternatively, an opening and closing sensor for detecting the opening and closing of the opening and closing valve 71 may be provided in the substrate processing unit 1B, and the time point at which the closed state has been detected by the opening and closing sensor may be used.

The image generation unit 17 combines the pixels of the same coordinates of the plural original images G0 The pixel values of are averaged or integrated and a derivative image G10 is generated. The derivative image G10 includes a temporal change in the state of the treatment liquid. Therefore, since the derivative image G10 contains the information of the original image G0 that has reflected the nozzle tip state, the determination rule K1 is applied to the derivative image G10, whereby the nozzle tip state can be determined, and the closing of the opening and closing valve 71 can be determined Speed distinction.

More specifically, for example, in the case where the droplet L2 falls due to the low closing speed of the opening and closing valve 71 (see also FIG. 5), it is considered that the pixel value (or brightness value) in the front area 52 of the derivative image G10 is changed. As large as the droplet L2. That is, the feature quantity of the derived image G12 corresponding to the front area 52 in the derived image G10 (the median pixel value of the gray scale, the sum of the brightness values, the standard deviation of the pixel values in the gray scale, or the standard deviation of the brightness) corresponds to The feature quantity becomes larger than that in the case where the locking speed is appropriate. In this case, the determination unit 14 compares the feature amount of the derivative image G12 with a predetermined reference amount (blank reference value), and when the feature amount is greater than the reference value, determines that the opening and closing speed is faster than the appropriate speed. Still low (that is, too low).

In addition, in the case where an air column is generated at the tip of the nozzle 251 due to the high closing speed of the opening and closing valve 71 (see also FIG. 5), it is considered that the pixel value (or brightness value) in the inner region 51 of the derivative image G10 is changed. As small as the weight of the air column. That is, the feature amount of the derivative image G11 corresponding to the inner region 51 in the derivative image G10 is smaller than the feature amount in the case where the locking speed is appropriate. In this case, the determining unit 14 compares the characteristic amount of the derivative image G11 with a predetermined reference amount (liquid-tightness reference value). When the characteristic amount is smaller than the reference value, it is determined that the opening and closing speed is faster than the appropriate speed. Still high (that is, too high).

(1-2) Adjustment of blocking speed

The control unit 130 determines the control parameter (pressure indicator) based on the classification of the closing speed of the on-off valve 71 determined by the determination device 300, and determines the control parameter (pressure indicator) so that the closing speed (more specifically, the closing speed in the later period T2) becomes an appropriate speed. Decrease speed β of value P1* 1, energy rate indication value D*, openness indication value or various gains, etc.).

For example, the pressure setting unit 12 determines the decrease speed β1 of the pressure instruction value P1* in the post period T2 based on the classification of the closing speed of the on-off valve 71 determined by the determination device 300. Specifically, the pressure setting unit 12 reduces the reduction speed β 1 in the subsequent period T2 when the locking speed is too high; and when the opening and closing speed is too low, reduces the reduction speed β 1 in the subsequent period T2. Increase. Thereby, the lock speed can be set to an appropriate speed, and the nozzle tip state when the ejection is stopped can be set more reliably and well.

Alternatively, in the case where the control signal generating unit 13 has a PID control unit 132, the PID control unit 132 can also determine various gains (proportional gain, integral gain, etc.) such that the blocking speed (especially the blocking speed in the later period T2) becomes an appropriate speed. Gain and derivative gain). The PID control unit 132 reduces the proportional gain when the blocking speed is too high, for example. In addition, the PID control unit 132 increases the proportional gain when the blocking speed is too high, for example. Thereby, the closing speed in the subsequent period T2 can be set to an appropriate speed, and the nozzle tip state when the ejection is stopped can be set more reliably and well.

(2) Operation of substrate processing unit 1B

FIG. 21 is a flowchart showing an example of the operation of the substrate processing unit 1B, and FIG. 22 is a diagram showing an example of the relationship between the nozzle tip state and the closing speed of the opening and closing valve 71 in a graph form.

In FIG. 22, each of the three states of "appropriate", "too high", and "too low" with respect to the closing speed of the on-off valve 71 is illustrated as "state 1 after stop" and "state 2 after stop". The two states are regarded as the nozzle tip state when the ejection is stopped. These two states are shown schematically by the camera 65 capturing the original image G0 of the photographic target area 50. In each original image G0 in FIG. 22, regions A and B are displayed. In addition, for the convenience of description, the suction action of the suction valve 72 is ignored here.

In the case where the closing speed of the opening and closing valve 71 is appropriate, immediately after stopping the ejection, process The lower end of the liquid L1 coincides with the front end 252 of the nozzle 251 or stops slightly above the front end 252. After the ejection is stopped, the droplet L2 does not fall from the tip 252 of the nozzle 251. That is, the state of the tip of the nozzle becomes a good state.

In the case where the closing speed of the opening and closing valve 71 is too low, the liquid droplet L2 does not fall in the stopped state 1, and the lower end surface of the processing liquid L1 faces downward from the front end 252 of the nozzle 251 and has a convex shape. In addition, in the second state after the stop, the droplet L2 falls, and the lower end of the processing liquid L1 coincides with the tip 252 of the nozzle 251. In addition, even when the droplet L2 falls, the lower end of the treatment liquid L1 does not necessarily have to coincide with the front end 252 of the nozzle 251, and the lower end of the treatment liquid L1 may maintain a convex shape. In this case, the drop of the liquid drop L2 and the lower end surface of the treatment liquid L1 have the same convex shape as the state after the stop at the same time.

When the closing speed of the on-off valve 71 is too high, in the state after the stop, so-called water tapping is generated at the tip of the nozzle except for the droplets L2 adhering to the inner wall surface and remaining on the tip 252 of the nozzle 251. There is no area of the treatment liquid L1 outside the droplet L2. The lower end surface of the processing liquid L1 is located far above the front end 252 of the nozzle 251. In addition, in the second state after the stop, a liquid droplet L2 of a size that closes the tip 252 of the nozzle 251 is generated. In addition, as in the stopped state, a region where the processing liquid L1 is not present is generated at the tip portion of the nozzle 251, and the lower end surface of the processing liquid L1 is located far above the tip 252 of the nozzle 251. In the post-stop state 1 and the post-stop state 2, the droplets L2 remaining at the tip of the nozzle 251 may become particles during drying.

Hereinafter, the operation of the substrate processing unit 1B (determination device 300) will be described with reference to FIG. 22 as appropriate and based on the flowchart of FIG. 21.

In step S210 of FIG. 21, the camera 65 captures the imaging target area 50 after the opening and closing valve 71 closes the flow path and the nozzle 251 stops spraying the treatment liquid L1. The imaging target area 50 is the internal area including the tip of the nozzle 251 51 (Figure 22) and the area in front of the tip 252 of the nozzle 251 52 (Figure 22). The captured image (that is, the original image) G0 is supplied to the control unit 130.

Next, in step S220, the feature amount calculation unit 15 calculates the feature amount for the first image G1 of the area A (FIG. 22) and the second image G2 of the area B (FIG. 22), and the area A is related to the tip of the nozzle 251 The internal area 51 in the flow path of φ corresponds to the area B corresponds to the front area 52 on the ejection path of the processing liquid L1 in the tip portion of the nozzle 251. In addition, the feature amount calculation unit 15 may also calculate the feature amount of the derivative images G11 and G12 to replace the first image G1 and the second image G2.

In addition, the regions A and B have the width of the tip (discharge port) 252 of the nozzle 251, and are set to be elongated in the discharge direction AR1 of the processing liquid L1.

Next, in step S230, the predetermined basic determination unit 16 determines whether the region A is in the liquid-tight state caused by the processing liquid L1 based on the feature amount of the first image G1 (or the derivative image G11). The feature quantity is, for example, the sum of the pixel values in the gray scale, the sum of the brightness values, the standard deviation of the pixel values in the gray scale, or the standard deviation of the brightness in the first image G1 (or the derivative image G11). For example, the predetermined basic determination unit 16 determines that the area A is in the liquid-tight state when the characteristic amount is greater than the liquid-tightness reference value, and determines that the area A is not in the liquid-tight state when the characteristic amount is less than the liquid-tightness reference value.

When the result of this determination is that the area A is not in a liquid-tight state, the predetermined basic determination unit 16 determines in step S240 that the closing speed of the on-off valve 71 is too high.

Next, in step S250, the pressure setting unit 12 determines the decrease speed β1 of the pressure instruction value P1* in the subsequent period T2 in such a way that the closing speed of the on-off valve 71 in the subsequent period T2 is lowered, and the processing proceeds to step S290. For example, the pressure setting unit 12 may subtract a predetermined amount Δβ1 from the reduction speed β1 and calculate a new reduction speed β1. Alternatively, the PID control unit 132 may change the various gains to a predetermined amount so that the locking speed in the subsequent period T2 becomes lower. In short, the control unit 130 changes the control parameter related to the rate of decrease of the supply pressure of the gas H1 in the subsequent period T2 to a predetermined amount in such a way that the blocking speed in the subsequent period T2 is lowered.

When the result of the determination in step S230 is that the area A is in a liquid-tight state, the processing system is shifted Go to step S260.

In step S260, the predetermined basic determination unit 16 determines whether or not the region B is in a state in which there is almost no processing liquid L1 (hereinafter referred to as a blank state) based on the feature amount of the second image G2 (or the derivative image G12). The feature quantity is, for example, the sum of the pixel values in the gray scale, the sum of the brightness values, the standard deviation of the pixel values in the gray scale, or the standard deviation of the brightness in the second image G2 (or the derivative image G12). For example, the predetermined basic determination unit 16 determines that the area B is in the blank state when the feature amount is smaller than the blank reference value, and determines that the area B is not in the blank state when the feature amount is greater than the blank reference value.

When the result of this determination is that the processing liquid L1 exists in the area B (that is, when it is not in a blank state), the processing system moves to step S270.

In step S270, the predetermined basic determination unit 16 determines that the closing speed of the on-off valve 71 is too low.

Next, in step S280, the pressure setting unit 12 sets the decreasing speed β1 of the pressure instruction value P1* in the subsequent period T2 so that the closing speed of the on-off valve 71 in the subsequent period T2 becomes higher. For example, the pressure setting unit 12 may add a predetermined amount Δβ 1 to the reduction speed β 1 and calculate a new reduction speed β 1. Alternatively, the PID control unit 132 may change the various gains to a predetermined amount so that the locking speed in the subsequent period T2 becomes higher. In short, the control unit 130 changes the control parameter related to the rate of decrease in the supply pressure of the gas H1 in the subsequent period T2 to a predetermined amount in a manner that the blocking speed in the subsequent period T2 is increased.

After step S250 or step S280, in step S290, in order to stop ejecting the processing liquid L1 with the set control parameter, the substrate processing unit 1B temporarily ejects the processing liquid L1 from the nozzle 251, and then stops the ejection again. After that, the processing system returns to step S210, and the substrate processing unit 1B performs each processing after step S210.

When the result of the determination in step S260 is that there is almost no treatment liquid in area B In the state of L1 (blank state), the substrate processing unit 1B ends the operation of FIG. 21.

In the operation of FIG. 21, the basic determination unit 16 is prescribed to use the determination rule K1 as the following rule: when the internal region 51 is not in a liquid-tight state, it is determined that the closing speed of the on-off valve 71 is too high; when the internal region 51 is liquid When the closed state and the processing liquid L1 exists in the front area 52, it is determined that the closing speed of the on-off valve 71 is too low. In addition, the predetermined basic determination unit 16 applies the determination rule K1 to the feature amount of the first image G1 (or the derivative image G11, the same applies hereafter) and the feature amount of the second image G2 (or the derivative image G12, the same applies hereafter), In this way, the distinction of the closing speed of the on-off valve 71 is determined. Since the first image G1 and the second image G2, which reflect the change in the nozzle tip state corresponding to the closing speed of the opening and closing valve 71, individually detect the presence of the image of the processing liquid and determine the classification of the closing speed of the opening and closing valve 71, The classification of the locking speed can be judged with high judgment accuracy.

As shown in FIG. 22, the end of the area A on the downstream side in the ejection direction AR1 of the processing liquid L1 is separated from the tip 252 of the nozzle 251 toward the upstream side of the ejection direction AR1 of the processing liquid L1. Therefore, the determination unit 14 does not use the image of the image region from the end of the first image G1 (inner region 51) to the tip 252 of the nozzle 251 in the downstream side of the ejection direction AR1 for the closing speed of the opening and closing valve 71 Judgment of distinction. This image area is an area where it is difficult to identify the relationship between the presence of the processing liquid L1 and the closing speed of the on-off valve 71 (refer to the post-stop state 1 and post-stop state 2 in the upper part of FIG. 22). That is, even if the tip of the nozzle is in good condition, since the lower end position of the processing liquid L1 is uneven at the tip of the nozzle 251, the state of the image area between the inner area 51 and the front area 52 (whether it is in a liquid-tight state) is Jagged. Therefore, even if the image area is in a liquid-tight state or a blank state, it is difficult to use this state as a basis to determine whether the nozzle tip state is good. Therefore, in the case where the image area is not used for determination, the accuracy of determination can be improved.

(3) Mechanical learning

In the above example, the determination unit 14 determines the division of the closing speed of the on-off valve 71 in accordance with the determination rule K1. However, it is not limited to this. For example, the judging unit 14 can also judge the opening and closing valve by mechanical learning. 71 to distinguish the locking speed.

FIG. 23 is a functional block diagram for schematically showing an example of the internal structure of the control unit 130. In the example of FIG. 23, the determination unit 14 includes a classifier K2. The classifier K2 is based on the image of the internal area 51 of the tip of the nozzle 251 and the image of the area 52 in front of the nozzle 251 in the original image G0 of the object area 50 captured by the camera 65 to determine which of the following is the closing speed of the on-off valve 71 Classification: the closing speed of the opening and closing valve 71 is appropriate, or the closing speed of the opening and closing valve 71 is higher than the appropriate speed, or the closing speed of the opening and closing valve 71 is lower than the appropriate speed. That is, the determination unit 14 determines the division of the closing speed of the on-off valve 71 by the classifier K2.

The control unit 130 is provided with a machine learning unit 18. The classifier K2 uses the sampling images of the internal area 51 of the tip of the nozzle 251 and the area 52 in front of the nozzle 251 in the original image G0 of the photographic target area 50 taken by the camera 65 and is performed by the machine learning unit 18 in advance. Generated by mechanical learning.

The machine learning unit 18 stores the generated classifier K2 on the disk 161. The classifier K2 is memorized, for example, as a program or parameter for realizing the function of the classifier K2. The machine learning unit 18 uses, for example, a neighborhood method, a support vector machine, a random forest classifier (random forest), a neural network, etc. as an algorithm for machine learning.

In addition, the machine learning unit 18 may also be updated periodically or irregularly in an off-line manner. In addition, it is also possible to further sample images (teacher data) for the machine learning unit 18 that has previously performed machine learning, and perform on-line learning and update.

In addition, although the substrate processing apparatus 100 includes a plurality of substrate processing units 1B, the classifier K2 generated for one substrate processing unit 1B by mechanical learning can also be used to control the on-off valve 71 in the other substrate processing unit 1B. .

FIG. 24 is a flow chart for showing an example of the above-mentioned operation of the substrate processing unit 1B Fig. 25 is a diagram for graphically showing an example of the relationship between the nozzle tip state when the ejection is stopped and the division of the closing speed of the on-off valve 71.

In step S310 of FIG. 24, the machine learning unit 18 sets the area C (FIG. 25) including the inside (flow path) of the tip portion of the nozzle 251 and the ejection path of the processing liquid L1 in front of the tip portion of the nozzle 251 The images are classified into groups with the closing speed of the on-off valve as "appropriate", "too high", and "too low" for mechanical learning. The machine learning unit 18 stores the classifier K2 generated by machine learning on the disk 161.

In addition, for the example of FIG. 22, in the case where the determination unit 14 applies the classifier K2, the classifier K2 is based on the original image G0 of the photographic subject area 50 captured by the camera 65 corresponding to the inner area 51 (FIG. 22) The image of each of the first image G1 of the area A and the second image G2 of the area B corresponding to the front area 52 (FIG. 22) determines the division of the closing speed of the on-off valve 71. The classifier K2 uses the sampled images of each of the first image G1 and the second image G2 and is generated by mechanical learning in advance.

In step S320, the camera 65 captures the imaging target area 50 when the on-off valve 71 closes the flow path and stops ejecting the treatment liquid L1 from the nozzle 251. The imaging target area 50 includes the interior (flow path) of the tip of the nozzle 251 And the ejection path of the processing liquid L1 ahead of the tip of the nozzle 251.

Next, in step S330, the determining unit 14 uses the classifier K2 to classify the image of the region C (or the first image G1 and the second image G2) in the captured image (original image) G0, and determine the opening and closing valve The division to which the locking speed of 71 belongs.

In addition, the area C has the width of the tip (discharge port) 252 of the nozzle 251, and is set to be elongated in the discharge direction AR1 of the processing liquid L1. The area C in FIG. 25 becomes a slightly longer area than the area after the areas A and B in FIG. 22 are merged. This is because the areas A and B are separated from each other.

In step S340, the determination unit 14 determines whether the locking speed has been classified (determined) as "too high".

When the result of the determination is that the locking speed has been classified as "too high", the processing system moves to step S350.

In step S350, the pressure setting unit 12 determines the decrease speed β1 of the pressure instruction value P1* in the subsequent period T2 so that the closing speed of the on-off valve 71 in the subsequent period T2 decreases, and the processing proceeds to step S380. For example, the pressure setting unit 12 may subtract a predetermined amount Δβ1 from the reduction speed β1 and calculate a new reduction speed β1. In short, the control parameter is changed to a predetermined amount by the way that the blocking speed in the subsequent period T2 becomes lower.

When the result of the determination in step S340 is that the closing speed of the on-off valve 71 is not classified as "too high", the processing system proceeds to step S360.

In step S360, the determination unit 14 determines whether the closing speed of the on-off valve 71 has been classified as "too low".

When the result of the determination is that the locking speed has been classified as "too low", the processing system moves to step S370.

In step S370, the pressure setting unit 12 determines the decrease speed β1 of the pressure instruction value P1* in the subsequent period T2 in such a way that the closing speed of the on-off valve 71 in the subsequent period T2 becomes higher. For example, the pressure setting unit 12 may add a predetermined amount Δβ 1 to the reduction speed β 1 and calculate a new reduction speed β 1. In short, the control parameter is changed to a predetermined amount by the way that the blocking speed in the subsequent period T2 becomes higher.

After step S350 or step S370, in step S380, in order to stop ejecting the processing liquid L1 with the set control parameter, the substrate processing unit 1B temporarily ejects the processing liquid L1 from the nozzle 251, and then stops the ejection again. After that, the processing system returns to step S320, and the substrate processing unit 1B performs each processing after step S320.

In the case where the result of the determination in step S360 is that the closing speed of the on-off valve 71 is not classified as "too low", the substrate processing unit 1B ends the operation of FIG. 24.

As mentioned above, even if mechanical learning is used, the locking speed can be adjusted according to the state of the nozzle tip. In addition, since the original image G0 (the first image G1 and the second image G2) that reflects the change in the nozzle tip state corresponding to the closing speed of the opening and closing valve 71 is used to determine the lock speed distinction, the High precision. In addition, in the case where the classifier K2 is applied to the first image G1 and the second image G2, since the area between the inner area 51 and the front area 52 is not used for the determination, the accuracy of the determination can be improved.

Fig. 26 is a schematic diagram showing an example of a model for machine learning. In the example of FIG. 26, a model of NN1 like neural network (including deep learning) NN1 is shown. The model is stored in the classifier K2. The model is provided with an input layer, an intermediate layer (hidden layer), and an output layer. Each layer system has a plurality of nodes (artificial nerve cells), and the output data of the node of the previous layer is input to each node. Each node system outputs, for example, the result of a well-known function. The number of intermediate layers is not limited to one layer, and can be set arbitrarily.

The judging unit 14 uses the classifier K2 to perform arithmetic processing on the output layer from the input layer through the intermediate layer, thereby enabling matching with respect to the nozzle tip state. More specifically, for example, the determination unit 14 matches the nozzle tip state in the captured image to any one of a plurality of groups (the six nozzle tip states shown in FIG. 22). In the example of FIG. 26, each group is schematically displayed by the corresponding image Gk. The characteristics of each group use each sampled image corresponding to each state of the above-mentioned sampled image (corresponding to each state of the processing liquid L1 just stopped in the part near the front end 252 (more specifically, the sum of the pixel value or brightness of each sampled image) , Or pixel value or standard deviation of brightness)) learning in advance.

The image GI (original image G0 (first image G1 and second image G2)) near the tip 252 of the nozzle 251 is input into the input layer. The captured image GI is determined by the determination unit 14 The image recognition performed by the executed neural network NN1 is matched to the group with the most similar characteristics. In addition, it can also be considered that the nozzle tip state of the image GI output by the determination unit 14 is classified into any one of the six nozzle tip states in FIG. 22.

Next, the determination unit 14 classifies the closing speed of the on-off valve 71 based on the classification result. For example, when the nozzle tip state in the image GI is classified into any one of the two nozzle tip states on the upper side of the paper in FIG. 26, the determination unit 14 classifies the closing speed of the on-off valve 71 into the "appropriate" group; When the nozzle tip state in the image GI is classified into either of the two nozzle tip states in the middle of the paper in FIG. 26, the closing speed of the on-off valve 71 is classified into the "too low" group; in the image GI When the nozzle tip state is classified into the two nozzle tip states on the lower side of the paper in FIG. 26, the closing speed of the on-off valve 71 is classified into the "too high" group. The operation shown in FIG. 26 corresponds to the processing of step S340 and step S360 described above.

In addition, in the above example, the determination unit 14 uses a neural network to classify the nozzle tip state of the image GI into six nozzle tip states, and classifies the locking speed according to the classification result, but it is not limited to this. The judging unit 14 can also directly classify the locking speed using a neural network. That is, the output layer may also classify the closing speed of the on-off valve 71 into three groups of "too high", "appropriate", and "too low".

In addition, the images GI and Gk in FIG. 26 show that the image near the tip 252 of the nozzle 251 is taken, but it is not necessarily only the image near the tip 252 of the nozzle 251. The overall image captured by the imaging element can also be used as a feature. Vector learning. In this case, it is considered that the machine learning unit 19 pays attention to the difference of the nozzle tip state that is generated in the plural overall images and performs learning.

(3-1) Derived image

The judging unit 14 can also make a judgment based on the derived image G10 instead of making a judgment based on the original image G0. Specifically, the determination unit 14 may also be based on the tip of the nozzle 251 in the derived image G10 The images of the inner area 51 and the area 52 in front of the nozzle 251 determine the division of the closing speed of the on-off valve 71. In this case, the classifier K2 is generated by the machine learning performed by the machine learning unit 18 using the sample images of the internal area 51 of the front end of the nozzle 251 and the front area 52 of the nozzle 251 in the derivative image G10.

(4) Suction valve

The determination unit 14 of the control unit 130 may also determine the distinction of the operating speed of the suction valve 72 based on the original image G0 (or the derivative image G10) captured by the camera 65.

FIG. 27 is a diagram showing an example of the relationship between the nozzle tip state and the division of the operating speed of the suction valve 27 in a graph form. In FIG. 27, the state where the operating speed of the suction valve 72 is "appropriate" is illustrated as "state 1 after stop" as the nozzle tip state when the ejection is stopped; for the state where the operating speed of the suction valve 72 is "too high" The two states of "state 1 after stopping" and "state 2 after stopping" are exemplified as the nozzle tip state when ejection is stopped. These two states are schematically displayed by the image G0 of the photographic target area 50 taken by the camera 65 respectively. In each image G0 in FIG. 27, a region D is displayed. The area D is an area corresponding to at least a part of the flow path between the end face position of the processing liquid after the suction operation and the tip 252 of the nozzle 251.

When the operating speed of the suction valve 72 is appropriate, immediately after the discharge is stopped, the lower end of the processing liquid L1 is stopped above the front end 252 of the nozzle 251. After the ejection is stopped, the droplet L2 does not fall from the tip 252 of the nozzle 251. That is, the state of the nozzle tip is in a good state.

In the case where the operating speed of the suction valve 72 is too high, the state of the tip of the nozzle becomes the state after stopping or state two after stopping. In the first state after the stop, the droplet L2 adheres to the inner wall surface of the tip portion of the nozzle 251 due to the rapid change in the volume of the flow path. In addition, in the second state after the stop, a droplet L2 adheres to the inner wall surface of the tip of the nozzle 251, and a liquid droplet L2 of a size that closes the tip 252 of the nozzle 251 is generated. In the post-stop state 1 and the post-stop state 2, the droplets L2 remaining at the tip of the nozzle 251 may become fine particles during drying.

The upper end of the inner area 53 corresponding to the area D is located, for example, lower than the lower end position of the processing liquid L1 when the operating speed of the suction valve 72 is appropriate, and the lower end of the inner area 53 approximately coincides with the tip 252 of the nozzle 251 . When the operating speed of the suction valve 72 is appropriate, the treatment liquid L1 hardly remains in the internal region 53; when the operation speed of the suction valve 72 is too high, the treatment liquid L1 remains in the internal region 53 L1 serves as droplet L2. That is, the internal area 53 is an area where the change in the nozzle tip state corresponding to the operating speed of the suction valve 72 can be visually recognized.

Therefore, the determination unit 14 focuses on the internal region 53 corresponding to the region D in the original image G0, and determines the distinction of the operating speed of the suction valve 72.

(4-1) Provisional basis

The feature amount calculation unit 15 of the determination unit 14 calculates a predetermined feature amount corresponding to the area of the image of the processing liquid L1 for the third image G3 corresponding to the inner region 53 in the original image G0. As the feature quantity, for example, the sum of the pixel values in the gray scale, the sum of the brightness, the standard deviation of the pixel values in the gray scale, or the standard deviation of the brightness of each pixel in the area of the third video G3 is used.

The predetermined basic determination unit 16 of the determination unit 14 applies a predetermined determination rule to the feature amount of the third image G3, thereby determining the division of the operating speed of the suction valve 72. As this determination rule, for example, as long as the internal region 53 is not in a blank state, it is determined that the operating speed of the suction valve 72 is too high. Here, the so-called blank state refers to a state in which the processing liquid L1 hardly remains in the inner region 53.

In addition, similarly to the determination processing in the on-off valve 71, the determination unit 14 may perform determination processing on the derivative image G10. The determination unit 14 calculates a predetermined feature amount corresponding to the area of the image of the processing liquid L1 for the derivative image G13 corresponding to the inner region 53 in the derivative image G10. As the feature quantity, for example, the sum of the pixel values in the gray scale of each pixel in the region of the derivative image G13, the sum of the brightness, the standard deviation of the pixel value in the gray scale, or the standard deviation of the brightness, etc. are used.

FIG. 28 is a flowchart for showing an example of the operation of the substrate processing unit 1B. In step S410, the camera 65 captures the nozzle 251 after the suction valve 72 ends the suction operation. The imaging target area 50 is the internal area 53 (FIG. 27) of the front end portion. The captured image (that is, the original image) G0 is supplied to the control unit 130.

In step S420, the feature amount calculation unit 15 is the feature amount of the third image G3 (or the derivative image G13) of the region D (FIG. 27) corresponding to the inner region 53 in the flow path of the tip portion of the nozzle 251. In addition, the area D has the width of the tip (discharge port) 252 of the nozzle 251, and is set to be elongated in the discharge direction AR1 of the processing liquid L1.

Next, in step S430, the predetermined basic determination unit 16 determines whether or not the area D is in a blank state based on the feature amount. The feature quantity is, for example, the sum of grayscale pixel values, the sum of brightness values, the standard deviation of pixel values in grayscale, or the standard deviation of brightness in the third image G3 (or the derivative image G13). For example, the predetermined basic determination unit 16 determines that the area D is in the blank state when the feature amount is smaller than the blank reference value, and determines that the area D is not in the blank state when the feature amount is greater than the blank reference value. As a result of this determination, as long as the area D is in a blank state, the operating speed of the suction valve 72 is appropriate, and the processing is terminated.

On the other hand, as a result of this determination, as long as the area D is not in a blank state, the predetermined basic determination unit 16 determines in step S440 that the operating speed of the suction valve 72 is too high.

Next, in step S450, the pressure setting unit 12 determines the decrease speed β 2 of the pressure instruction value P2* (more specifically, the decrease speed β 2 during the operation period Tc2) such that the operating speed of the suction valve 72 becomes lower. ). For example, the pressure setting unit 12 subtracts a predetermined value Δβ 2 from the reduction speed β 2 and calculates a new reduction speed β 2. Alternatively, the PID control unit 132 may change various gains to a predetermined amount so that the operating speed during the operating period Tc2 becomes higher. In short, the control unit 130 changes the control parameter related to the decrease speed of the supply pressure of the gas H2 in the operation period Tc2 to a predetermined amount so that the operation speed of the suction valve 72 in the operation period Tc2 decreases.

Next, in step S460, the substrate processing unit 1B temporarily ejects the processing liquid L1 from the nozzle 251 by performing a suck-back operation according to the set control parameter, and then stops the ejection again. Of After that, the processing system returns to step S410, and the substrate processing unit 1B performs each processing after step S410.

As described above, according to the substrate processing unit 1B, the operation speed of the suction valve 72 is determined based on the third image G3 (or the derivative image G13) reflecting the change in the nozzle tip state corresponding to the operation speed of the suction valve 72 Therefore, it is possible to appropriately determine the division of the movement speed. In addition, the operating speed of the suction valve 72 can be adjusted in accordance with the determination result such that the state of the nozzle tip becomes good.

(4-2) Mechanical learning

In the above example, the determination unit 14 determines the division of the operating speed of the suction valve 72 in accordance with the determination rule. However, it is not limited to this. For example, similarly to the determination process of the opening and closing valve 71, the determination unit 14 may determine the division of the operating speed of the suction valve 72 by mechanical learning. That is, the machine learning unit 18 uses the camera 65 to take a sample image of the internal region 53 of the tip of the nozzle 251 in the original image G0 of the photographic target region 50 (or the internal region of the tip of the nozzle 251 in the derivative image G10). 53 sampled images), mechanical learning is performed in advance and a classifier is generated. The classifier is recorded on the magnetic disk 161, for example. The determining unit 14 inputs the third image G3 (or the derivative image G13) of the original image G0 captured by the camera 65 to the classifier, and thereby uses the classifier to determine the movement speed of the suction valve 72.

In this way, since the third image G3 (or the derivative image G13) that reflects the change in the nozzle tip state corresponding to the operating speed of the suction valve 72 is used to determine the operation speed distinction, the accuracy of the determination is high. .

FIG. 29 is a diagram schematically showing a control unit 130B as a configuration example of another embodiment of the control unit 130 of the substrate processing apparatus 100.

As shown in FIG. 29, the machine learning unit 18 is installed in the server 23, and the server 23 is installed outside the substrate processing apparatus 100. The machine learning department performed by the machine learning section 18 is performed offline. In addition, the determination unit 14 and the classifier K2 are also provided in the server 23. The control unit 130B The communication unit 21 is connected to the network 22, and the external server 23 is connected to the network 22.

The CPU 11 of the control unit 130B communicates information with the determination unit 14, the machine learning unit 18, and the classifier K2 provided in the server 23 via the communication unit 21 and the network 22. The control unit 130B is configured to be the same as the control unit 130 except that the machine learning unit 18, the determination unit 14 and the classifier K2 are not provided with the control unit 130. The control unit 130B sends the image captured by the imaging unit 65 to the server 23 via the communication unit 21, and receives the calculation result (classification result) performed by the server 23 via the communication unit 21. The pressure setting unit 12 determines the pressure indicating value P1* in accordance with the classification result.

With this, since the server 23 is provided with a determination function (the determination unit 14 and the classifier K2), it is possible to perform matching (determination) common to a plurality of substrate processing units 1B. In addition, in FIG. 29, the image generating unit 17 may also be provided in the server 23. In addition, the aspect of FIG. 29 can also be applied to the aspect of FIG. 20. That is, the determination unit 14 (or the image generation unit 17) of FIG. 20 may be provided in the server 23.

In this case, an apparatus including the entire substrate processing apparatus 100 and the server 23 can be regarded as a processing liquid ejection apparatus.

In addition, the machine learning unit 18 may be updated periodically or irregularly in an offline manner. In addition, it is also possible to further sample images (teacher data) for the machine learning unit 18 that has undergone machine learning, and perform online learning and update. Furthermore, other CPUs can also be used via the network 22, and online learning can be performed on sampled images (teacher data).

FIG. 30 is a diagram schematically showing a control unit 130C as a configuration example of another embodiment of the control unit 130 of the substrate processing apparatus 100. As shown in FIG. 30, the control unit 130C is configured to be the same as the control unit 130, and performs the same operation except that the classifier K2 is stored in the ROM 162 instead of the classifier K2 in the magnetic disk 161. In this way, the classifier K2 can also be stored in the ROM162.

(5) Types of valves

In the second embodiment, the on-off valve 71A, the suction valve 72A, and the drive mechanism can also be used 74A and 75A replace the on-off valve 71, the suction valve 72, and the drive mechanisms 74 and 75.

Although the processing liquid ejection method and the processing liquid ejection device have been illustrated and described in detail, the foregoing description is illustrative and not restrictive in all aspects. Therefore, the processing liquid ejection method and processing liquid ejection device can be changed or omitted as appropriate in the embodiment.

P1*‧‧‧Pressure indication value (target value)

P1[0]‧‧‧Value

PL1, PH1‧‧‧reference value

Pm1‧‧‧Measured value

t10 to t13‧‧‧time point

Before T1‧‧‧

Period after T2‧‧‧

Ta1‧‧‧Valve control period

Tb1‧‧‧Non-operation period

Tc1‧‧‧During lockout

Claims (18)

A method of discharging a processing liquid includes: a first step of discharging from a nozzle the processing liquid supplied to the nozzle via a pipe; and a second step of discharging the processing liquid from the nozzle when stopping the treatment liquid from the nozzle and setting it in the pipe The movement speed or deformation speed of the valve body of at least one valve changes during the operation period of the valve; the operation period is the period during which the valve body starts to move until it stops; the at least one valve system includes: gas actuation The valve switches the opening and closing of the flow path in the piping and opens and closes in response to the pressure of the gas supplied from the driving mechanism; when the operating speed when the gas actuated valve is closed is defined as the closing speed, in the second step , Controlling the gas actuated valve so that the closing speed in the first period in the operation period is set to be higher than the closing speed in the second period after the first period in the operation period, and The instruction value corresponding to the pressure of the gas is updated stepwise during the operation period, the drive mechanism is controlled based on the instruction value, and the closing speed of the gas actuated valve is changed during the operation period. The processing liquid ejection method described in claim 1, wherein the gas system is supplied to the gas actuating valve via a gas supply pipe; the pressure in the gas supply pipe is measured by a pressure sensor; and in the second step, The measurement value measured by the pressure sensor causes the indicator value corresponding to the pressure of the gas to be updated step by step during the operation period. The processing liquid ejection method described in claim 1 or 2, wherein during the aforementioned second period The number of updates of the aforementioned indicator value is more than the number of updates in the aforementioned first period. The processing liquid ejection method described in claim 2, wherein in the second step, proportional control, proportional integral control, or proportional integral derivative control is performed for the difference between the indicated value and the measured value and the drive mechanism is controlled, In this way, the aforementioned motion speed is controlled. The processing liquid ejection method according to claim 1 or 2, wherein the at least one valve includes a suction valve that sucks the processing liquid back into the nozzle when the ejection of the processing liquid is stopped. The process liquid ejection method according to claim 1 or 2, wherein in the second step, the pressure of the gas changes during the non-operation period until the valve body of the gas actuated valve starts to move or start to deform The driving mechanism is controlled so that the speed becomes higher than the change speed of the pressure of the gas during the operation period. The processing liquid ejection method described in claim 1 or 2, which includes: a third step of photographing the tip of the nozzle from a direction different from the ejection direction of the nozzle when the ejection of the processing liquid from the nozzle is stopped. The flow path of the part; and the fourth step are to perform a predetermined determination process based on the original image captured by the imaging part in the third step, thereby determining whether the operating speed of the at least one valve is appropriate. The processing liquid ejection method according to claim 7, wherein the at least one valve system includes: an opening and closing valve that switches the opening and closing of the flow path in the piping; when the opening and closing valve is closed, the operating speed when the opening and closing valve is closed is defined as the closing speed When the fourth step includes the following steps: the first image in the first image area corresponding to the flow path of the tip of the nozzle in the original image and the flow path along the processing liquid from the tip of the nozzle Squirting For each image of the second image in the second image area corresponding to the ejection path of the processing liquid extending in the forward direction, calculate the difference between the image of the processing liquid in the image of each of the first image and the second image A predetermined first characteristic amount corresponding to the area; and applying a predetermined first determination rule to the first characteristic amount of the first image and the first characteristic amount of the second image, thereby determining that the locking speed is below What kind of distinction: Is the aforementioned locking speed appropriate, or the aforementioned locking speed higher than the appropriate speed, or the aforementioned locking speed lower than the appropriate speed. The processing liquid ejection method described in claim 8, wherein the first determination rule is the following rule: when the flow path at the tip of the nozzle is not in a liquid-tight state, it is determined that the closing speed of the on-off valve is higher than the foregoing The appropriate speed is also high; when the flow path at the tip of the nozzle is in a liquid-tight state and the processing liquid exists in the ejection path, it is determined that the blocking speed is lower than the appropriate speed. The processing liquid ejection method according to claim 7, wherein the at least one valve system includes: an opening and closing valve that switches the opening and closing of the flow path in the piping; when the opening and closing valve is closed, the operating speed when the opening and closing valve is closed is defined as the closing speed In the fourth step, based on the flow path of the tip of the nozzle in the original image and the image of the ejection path of the processing liquid extending forward from the tip of the nozzle along the ejection direction of the processing liquid, borrow The classifier determines the distinction of the aforementioned locking speed. The aforementioned classifier determines the aforementioned locking speed which is the following distinction: the aforementioned locking speed is appropriate, or the aforementioned locking speed is higher than the appropriate speed, or the aforementioned locking speed is greater than The appropriate speed is also low; the classifier is generated by mechanical learning in advance using the flow path of the nozzle tip and the sampling image of the ejection path in the original image. The processing liquid ejection method described in claim 10, wherein in the fourth step, the first image in the first image area corresponding to the flow path of the tip of the nozzle in the original image and the ejection path The images of each of the second images corresponding to the second image area determine the distinction of the locking speed of the opening and closing valve; the classifier uses the sampled images of each of the first image and the second image and is pre-machined Generated by learning. The processing liquid ejection method according to claim 8, wherein the end of the first image area in the downstream side of the ejection direction of the processing liquid is separated from the tip of the nozzle to the upstream side of the ejection direction of the processing liquid. The processing liquid ejection method described in claim 7, wherein the at least one valve system includes: a suction valve that sucks the processing liquid in the nozzle back when the processing liquid is stopped, so that the end face position of the processing liquid is changed from the foregoing The tip of the nozzle is far away; the fourth step includes the following step: for the third image area corresponding to at least a part of the flow path between the end face position of the processing liquid and the tip of the nozzle in the original image For the third image, a predetermined second characteristic amount corresponding to the area of the image of the treatment liquid is calculated; and a predetermined second determination rule is applied to the second characteristic amount of the third image, thereby determining the suction The aforementioned operating speed of the valve is classified as follows: the aforementioned operating speed of the suction valve is appropriate, or the aforementioned operating speed of the aforementioned suction valve is higher than the appropriate speed. The processing liquid ejection method described in claim 13, wherein the second determination rule is that when the processing liquid remains in at least a part of the flow path between the end face position of the processing liquid and the tip of the nozzle, it is determined that the suction The aforementioned movement speed of the return valve is faster than before The appropriate speed is still high. The processing liquid ejection method described in claim 7, wherein the at least one valve system includes: a suction valve that sucks the processing liquid in the nozzle back when the processing liquid is stopped, so that the end face position of the processing liquid is changed from the foregoing The tip of the nozzle is far away; in the fourth step, based on the third image in the third image area corresponding to at least a part of the flow path between the end face position of the processing liquid and the tip of the nozzle in the original image, The classifier determines the operating speed of the suction valve, and the classifier determines which of the following is the operating speed of the suction valve: the operating speed of the suction valve is appropriate or the speed of the suction valve is The action speed is higher than the appropriate speed; the aforementioned classifier is generated by using the sampled image of the aforementioned third image and pre-generated by mechanical learning. The processing liquid ejection method according to claim 7, wherein in the third step, after the ejection of the processing liquid from the nozzle is stopped, the imaging unit sequentially photographs the flow path of the tip of the nozzle in time; The four-step system includes the following steps: averaging or accumulating a plurality of original images shot by the shooting unit to generate a derivative image; and determining whether the operating speed of the at least one valve is appropriate based on the derivative image. The processing liquid ejection method described in claim 7, further comprising: a fifth step, which is based on whether the operating speed of the at least one valve determined in the fourth step is appropriate, and the operating speed becomes the appropriate The speed is adjusted to adjust the action of the at least one valve in the first step. A processing liquid ejection device is provided with: a nozzle for ejecting the processing liquid; a pipe connecting the nozzle and the processing liquid supply source to guide the processing liquid from the processing liquid supply source to the nozzle; at least one valve, Provided in the piping; and a control unit that changes the movement speed or the deformation speed of the valve body of the at least one valve during the operation period of the at least one valve when the treatment liquid is stopped from the nozzle; The period is the period when the valve body starts to move until it stops; the at least one valve system includes: a gas-actuated valve that switches the opening and closing of the flow path in the piping, and opens and closes in response to the pressure of the gas supplied from the drive mechanism; when When the operation speed when the gas operating valve is closed is defined as the lock speed, the control unit sets the lock speed in the first period of the operation period to be later than the first period in the operation period. In the second period, the gas actuated valve is controlled so that the lock speed is still high, and the indicator value corresponding to the pressure of the gas is updated step by step during the operation period, and the drive mechanism is controlled according to the indicator value, and During the operation period, the closing speed of the gas actuated valve is changed.

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