Coating method and storage medium

Abstract

The present invention provides a technology for readjusting the ejection control parameters while suppressing the consumption of the substrate. In step S6, it is evaluated whether the actual coating pressure waveform (Wr1) obtained by the actual coating in step S5 is the same as the first ideal waveform (Wt1). When it is evaluated in step S6 that the actual coating pressure waveform (Wr1) is different from the first ideal waveform (Wt1), the ejection control parameters are readjusted. In the readjustment of the ejection control parameters, step S7 of updating the ejection control parameters, step S8 of obtaining a simulated coating pressure waveform by performing simulated coating, and step S9 of evaluating whether the simulated coating pressure waveform is the same as the second ideal waveform (Wt2) are performed.

Description

Technical Field

[0001] The subject matter disclosed in this specification relates to coating methods, programs, and storage media. Background Art

[0002] In the manufacturing process of flat panel displays (FPDs), substrate processing equipment called coaters are sometimes used. Coaters discharge a processing liquid, such as a resist solution, from a nozzle onto a substrate such as glass while scanning the nozzle across the substrate. The coater applies pressure to the processing liquid, such as the resist solution, causing it to be discharged from the nozzle. Furthermore, a movement mechanism moves the substrate relative to the nozzle, forming a coating film of the processing liquid on the substrate surface.

[0003] In such a substrate processing device, it is sometimes necessary to make the film thickness of the coating film uniform across the entire substrate. In order to make the film thickness uniform, the discharge control parameters are appropriately adjusted. In this adjustment operation, for example, a technician visually confirms the waveform of the discharge pressure while adjusting multiple discharge control parameters. Therefore, the adjustment operation depends largely on the technician's knowledge and experience. Therefore, the adjustment of the discharge control parameters requires a lot of time and energy from the technician. In addition, a large amount of processing liquid and substrate may be consumed. Therefore, effective techniques for adjusting control parameters have not been proposed to date.

[0004] For example, Patent Document 1 describes a technique for optimizing discharge control parameters. Specifically, the technique includes a simulated discharge process for discharging a processing liquid onto a portion of a substrate, a discharge characteristic measurement process for measuring the discharge characteristics of the processing liquid during the simulated discharge process, a state quantity derivation process for deriving a state quantity representing the deviation between the measured discharge characteristic and the target characteristic, and a learning process for performing machine learning on the changes in the state quantity accompanying parameter changes to construct a learning model. While the state quantity exceeds a predetermined allowable range, the parameters are changed based on the learning model, and the simulated discharge process, discharge characteristic measurement process, state quantity derivation process, and learning process are repeated. On the other hand, when the state quantity is within the allowable range, the last changed parameter is set as the parameter for discharging the processing liquid during the processing liquid supply process.

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2020-040046

[0006] However, when applying the treatment liquid to a substrate using the optimized discharge control parameters described in Patent Document 1, the pressure waveform of the discharge pressure may differ due to differences in conditions between the simulated discharge and the actual coating process. If the pressure waveform changes during actual coating, the discharge control parameters must be readjusted based on repeated coating cycles, potentially leading to excessive substrate consumption. Summary of the Invention

[0007] An object of the present invention is to provide a technology capable of suppressing substrate consumption and readjusting ejection control parameters.

[0008] To address the aforementioned issues, a first solution is a method for applying a treatment liquid to a substrate, comprising: a) an actual coating step, in which the substrate is moved relative to a nozzle according to pre-set discharge control parameters, and the treatment liquid is discharged from the nozzle onto the substrate; b) a first acquisition step, in which an actual coating pressure waveform representing the temporal change in discharge pressure from the nozzle during the actual coating step is acquired; c) a first evaluation step, in which the actual coating pressure waveform is evaluated; and d) a readjustment step, in which the discharge control parameters are readjusted based on the evaluation results of the first evaluation step. The readjustment step includes: d1) a first simulated coating step, in which the treatment liquid is simulatedly discharged from the nozzle onto a portion other than the substrate according to the discharge control parameters; d2) a second acquisition step, in which a first simulated coating pressure waveform representing the temporal change in discharge pressure during the first simulated coating step is acquired; d3) a second evaluation step, in which the first simulated coating pressure waveform is evaluated; and d4) a first update step, in which the discharge control parameters are updated based on the evaluation results of the second evaluation step.

[0009] According to the second scheme of the coating method of the first scheme, the first evaluation process includes a process for evaluating based on the deviation between the actual coating pressure waveform and the first ideal waveform, and the second evaluation process includes a process for evaluating based on the deviation between the first simulated coating pressure waveform and a second ideal waveform whose shape is different from the first ideal waveform.

[0010] According to a third aspect of the coating method of the second aspect, the second ideal waveform has a shape obtained by deforming the first ideal waveform according to a difference between the actual coating pressure waveform and the first ideal waveform.

[0011] A fourth aspect of any one of the first to third aspects further includes: e) a pre-adjustment step of adjusting the discharge control parameters before the first acquisition step. The pre-adjustment step includes: e1) a second simulated coating step of performing the simulated coating according to the preset discharge control parameters; e2) a third acquisition step of acquiring a second simulated coating pressure waveform representing the temporal change of the discharge pressure in the second simulated coating step; e3) a third evaluation step of evaluating the second simulated coating pressure waveform; and e4) a second update step of updating the discharge control parameters based on the evaluation results of the third evaluation step.

[0012] A fifth aspect is a storage medium having a computer-readable program recorded thereon, the program causing the computer to execute any one of the first to fourth aspects.

[0013] According to the coating method of the first aspect, when the actual coating pressure waveform is not the ideal waveform, the discharge control parameters are readjusted based on the pressure waveform obtained by the simulated coating. This allows the discharge control parameters to be readjusted while suppressing substrate consumption.

[0014] The coating method of the third embodiment readjusts the discharge control parameters using a second ideal waveform, which is a deformation of the first ideal waveform based on the difference between the actual coating pressure waveform and the first ideal waveform, as a reference. This effectively readjusts the discharge control parameters so that the pressure waveform during actual coating matches the first ideal waveform.

[0015] According to the coating method of the fourth aspect, the control parameter is adjusted based on the evaluation of the second simulated coating pressure waveform measured by the simulated coating. Therefore, the control parameter can be adjusted without consuming the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 : is a diagram schematically showing the entire configuration of a coating device according to an embodiment.

[0017] Figure 2 It is a diagram showing the structure of the processing liquid supply mechanism.

[0018] Figure 3 It shows Figure 2 A graph showing the movement pattern of the working disc of the pump is shown.

[0019] Figure 4 This is a block diagram showing a configuration example of a control unit.

[0020] Figure 5 This is a flowchart showing the adjustment process of the discharge control parameters.

[0021] Figure 6 : is a diagram showing a setting example of the second ideal waveform.

[0022] Description of Reference Numerals

[0023] 1: Coating device

[0024] 5: Mobile mechanism

[0025] 7: Coating mechanism

[0026] 71: Nozzle

[0027] 72: Roller

[0028] 8: Treatment fluid supply mechanism

[0029] 9: Control unit

[0030] 81: Pump

[0031] 86: Pressure gauge

[0032] 910: Discharge control unit

[0033] 911: Discharge pressure measuring unit

[0034] 915: Discharge control parameter adjustment unit

[0035] 931: Procedure

[0036] Wr1: Actual coating pressure waveform

[0037] Wt1: first ideal waveform

[0038] Wt2: The second ideal waveform DETAILED DESCRIPTION

[0039] The following describes embodiments of the present invention with reference to the accompanying drawings. It should be noted that the components described in these embodiments are merely examples and the scope of the present invention is not limited thereto. In the accompanying drawings, the dimensions and quantities of various components may be exaggerated or simplified as necessary to facilitate understanding.

[0040] 1. Implementation Method

[0041] Figure 1 is a diagram showing the overall structure of a coating apparatus 1 according to an embodiment. The coating apparatus 1 is a substrate processing apparatus that applies a processing liquid to the upper surface Sf of a substrate S. The substrate S is, for example, a glass substrate for a liquid crystal display device. It should be noted that the substrate S may also be a semiconductor wafer, a glass substrate for a photomask, a glass substrate for a plasma display, a glass substrate or a ceramic substrate for a magneto-optical disk, a glass substrate for an organic EL, a glass substrate or a silicon substrate for a solar cell, other flexible substrates, a printed circuit board, and other various substrates to be processed for electronic devices. The coating apparatus 1 is, for example, a slit coater.

[0042] exist Figure 1 In order to illustrate the configuration relationship of each element of the coating device 1, an XYZ coordinate system is defined. The moving direction of the substrate S is the "X direction". The direction in which the substrate S moves in the X direction (the direction downstream of the moving direction) is the +X direction, and the opposite direction (the direction upstream of the moving direction) is the -X direction. In addition, the direction orthogonal to the X direction is the Y direction, and the direction orthogonal to the X and Y directions is the Z direction. In the following description, the Z direction is set as the vertical direction, and the X and Y directions are set as horizontal directions. In the Z direction, the +Z direction is set as the upper direction, and the -Z direction is set as the lower direction.

[0043] The coating apparatus 1 includes, in order from the +X direction, an input conveyor 100, an input transfer unit 2, a lift platform 3, an output transfer unit 4, and an output conveyor 110. The input conveyor 100, the input transfer unit 2, the lift platform 3, the output transfer unit 4, and the output conveyor 110 form a movement path for the substrate S. The coating apparatus 1 also includes a movement mechanism 5, a coating mechanism 7, a process liquid supply mechanism 8, and a control unit 9.

[0044] The substrate S is conveyed from the upstream side to the input conveyor 100. The input conveyor 100 includes a roller conveyor 101 and a rotation drive mechanism 102. The rotation drive mechanism 102 rotates the rollers of the roller conveyor 101. The rotation of the rollers of the roller conveyor 101 conveys the substrate S in a horizontal position downstream (in the +X direction). The "horizontal position" means that the main surface (the surface with the largest area) of the substrate S is parallel to the horizontal plane (XY plane).

[0045] The input transfer unit 2 includes a roller conveyor 21 and a rotary lift drive mechanism 22. The rotary lift drive mechanism 22 rotates the rollers of the roller conveyor 21 and simultaneously raises and lowers the roller conveyor 21. The rotation of the roller conveyor 21 transports the substrate S in a horizontal position downstream (in the +X direction). Furthermore, the raising and lowering of the roller conveyor 21 changes the position of the substrate S in the Z direction. The substrate S is transferred from the input conveyor 100 to the floating platform 3 via the input transfer unit 2.

[0046] like Figure 1 As shown, the lifting platform portion 3 is roughly flat. The lifting platform portion 3 is divided into three parts along the X direction. The lifting platform portion 3 includes, in sequence toward the +X direction, an inlet lifting platform 31, a coating platform 32, and an outlet lifting platform 33. The upper surface of the inlet lifting platform 31, the upper surface of the coating platform 32, and the upper surface of the outlet lifting platform 33 are on the same plane. The lifting platform portion 3 also includes a lifting pin drive mechanism 34, a lifting control mechanism 35, and a lifting drive mechanism 36. A plurality of lifting pins are arranged on the inlet lifting platform 31. The lifting pin drive mechanism 34 lifts and lowers a plurality of lifting pins. The lifting control mechanism 35 supplies compressed air for lifting the substrate S to the inlet lifting platform 31, the coating platform 32, and the outlet lifting platform 33. The lifting drive mechanism 36 lifts and lowers the outlet lifting platform 33.

[0047] On the upper surface of the inlet lift platform 31 and the upper surface of the outlet lift platform 33, a large number of ejection holes for ejecting compressed air supplied from the lift control mechanism 35 are arranged in a matrix shape. When the compressed air is ejected from each ejection hole, the substrate S floats upward relative to the lift platform portion 3. Thereafter, the lower surface Sb of the substrate S is separated from the upper surface of the lift platform portion 3 while being supported in a horizontal posture. Preferably, when the substrate S is in the floating state, the distance (lifting amount) between the lower surface Sb of the substrate S and the upper surface of the lift platform portion 3 is greater than 10um. The distance is preferably less than 500um.

[0048] On the upper surface of the coating station 32, there are alternately arranged ejection holes for ejecting compressed air supplied from the levitation control mechanism 35 and suction holes for sucking gas along the X direction and the Y direction. The levitation control mechanism 35 controls the ejection amount of compressed air from the ejection holes and the suction amount of air from the suction holes. In this way, the levitation amount of the substrate S relative to the coating station 32 can be precisely controlled so that the position of the upper surface Sf of the substrate S passing over the coating station 32 in the Z direction is a specified value. It should be noted that the levitation amount of the substrate S relative to the coating station 32 is calculated by the control unit 9 based on the detection results of the sensor 61 or the sensor 62 described later. In addition, preferably, the levitation amount of the substrate S relative to the coating station 32 can be adjusted with high precision by airflow control.

[0049] The substrate S loaded onto the floating stage 3 is conveyed to the entrance floating stage 31 by receiving a propulsion force in the +X direction from the roller conveyor 21. The entrance floating stage 31, the coating stage 32, and the exit floating stage 33 support the substrate S in a floating state. The floating stage 3 can adopt the structure described in Japanese Patent No. 5346643, for example.

[0050] The moving mechanism 5 is disposed below the lift table 3. It includes a chuck mechanism 51 and a suction travel mechanism 52. The chuck mechanism 51 includes a suction pad (not shown) provided on a suction component. The chuck mechanism 51 supports the substrate S from below, with the suction pad in contact with the peripheral edge of the lower surface Sb of the substrate S. The suction travel mechanism 52 applies negative pressure to the suction pad, thereby adsorbing the substrate S to the suction pad. Furthermore, the suction travel mechanism 52 causes the chuck mechanism 51 to reciprocate in the X direction.

[0051] The chuck mechanism 51 holds the substrate S with its lower surface Sb positioned higher than the upper surface of the lift table 3. With the periphery of the substrate S held by the chuck mechanism 51, the substrate S maintains a horizontal posture by receiving buoyancy from the lift table 3.

[0052] like Figure 1As shown, the coating apparatus 1 includes a sensor 61 for measuring the plate thickness. The sensor 61 is disposed near the roller conveyor 21. The sensor 61 detects the position in the Z direction of the upper surface Sf of the substrate S held by the chuck mechanism 51. Furthermore, by positioning the chuck (not shown) directly below the sensor 61 so as not to hold the substrate S, the sensor 61 can detect the position in the vertical direction Z of the suction surface of the upper surface of the suction member.

[0053] The chuck mechanism 51 moves in the +X direction while holding the substrate S loaded onto the lift table 3. As a result, the substrate S is transferred from above the entrance lift table 31, through above the coating table 32, and finally to above the exit lift table 33. Thereafter, the substrate S moves from the exit lift table 33 to the output transfer unit 4.

[0054] The output transfer unit 4 moves the substrate S from a position above the exit floating platform 33 to the output conveyor 110. The output transfer unit 4 includes a roller conveyor 41 and a rotary lift drive mechanism 42. The rotary lift drive mechanism 42 rotates the roller conveyor 41 while simultaneously lifting and lowering it in the Z direction. The rotation of the rollers of the roller conveyor 41 moves the substrate S in the +X direction. Furthermore, the lifting and lowering of the roller conveyor 41 displaces the substrate S in the Z direction.

[0055] The output conveyor 110 includes a roller conveyor 111 and a rotation drive mechanism 112. The output conveyor 110 transports the substrate S in the +X direction by rotating the rollers of the roller conveyor 111, and discharges the substrate S out of the coating apparatus 1. It should be noted that the input conveyor 100 and the output conveyor 110 are part of the coating apparatus 1. However, the input conveyor 100 and the output conveyor 110 can be assembled as a device independent of the coating apparatus 1.

[0056] The coating mechanism 7 applies the treatment liquid to the upper surface Sf of the substrate S. The coating mechanism 7 is arranged above the moving path of the substrate S. The coating mechanism 7 has a nozzle 71. The nozzle 71 is a slit nozzle having a slit-shaped discharge port on the lower surface. The nozzle 71 is connected to a positioning mechanism (not shown). The positioning mechanism positions the nozzle 71 at a coating position ( Figure 1 The processing liquid supply mechanism 8 is connected to the nozzle 71. The processing liquid is supplied to the nozzle 71 by the processing liquid supply mechanism 8, and the processing liquid is discharged from the discharge port arranged on the lower surface of the nozzle 71.

[0057] In the coating device 1, the substrate S is moved relative to the nozzle 71 that discharges the processing liquid by the moving mechanism 5, and the processing liquid is coated on the substrate S. However, the moving mechanism 5 may be configured to move the nozzle 71 relative to the substrate S arranged at a fixed position. In addition, the moving mechanism 5 may be configured to move both the nozzle 71 and the substrate S. In this case, the moving direction of the substrate S may be opposite to the moving direction of the nozzle 71. In addition, the moving direction of the substrate S may be the same as the moving direction of the nozzle 71. In this case, the moving mechanism 5 may transport the nozzle 71 and the substrate S so that the nozzle 71 catches up with the substrate S at a speed faster than the speed of the substrate S being transported.

[0058] Figure 2 : is a diagram showing the structure of the treatment liquid supply mechanism 8. The treatment liquid supply mechanism 8 includes a pump 81, a pipe 82, a treatment liquid replenishing unit 83, a pipe 84, an on-off valve 85, a pressure gauge 86, and a drive unit 87. The pump 81 is a supply source for supplying the treatment liquid to the nozzle 71, and it supplies the treatment liquid by changing its volume. The pump 81 can be, for example, a bellows pump described in the Japanese Patent Publication No. 10-61558. Figure 2 As shown, the pump 81 includes a flexible tube 811 that is elastically expandable and contractible in the radial direction. One end of the flexible tube 811 is connected to the processing liquid replenishing unit 83 via a pipe 82. The other end of the flexible tube 811 is connected to the nozzle 71 via a pipe 84.

[0059] The pump 81 includes a bellows 812 that is elastically deformable in the axial direction. The bellows 812 includes a small bellows portion 813, a large bellows portion 814, a pump chamber 815, and a working disc portion 816. The pump chamber 815 is located between the flexible tube 811 and the bellows 812. An incompressible medium is enclosed in the pump chamber 815. The working disc portion 816 is connected to the drive unit 87.

[0060] The treatment liquid replenishing unit 83 includes a storage tank 831 for storing treatment liquid. The storage tank 831 is connected to the pump 81 via a pipe 82. An on-off valve 833 is attached to the pipe 82. The on-off valve 833 opens and closes in response to commands from the control unit 9. When the on-off valve 833 is open, the treatment liquid can be replenished from the storage tank 831 to the flexible tube 811 of the pump 81. On the other hand, when the on-off valve 833 is closed, the replenishment of the treatment liquid from the storage tank 831 to the flexible tube 811 of the pump 81 is restricted.

[0061] The pipe 84 is connected to the output side of the pump 81. An on-off valve 85 is attached to the pipe 84. The on-off valve 85 opens and closes in response to commands from the control unit 9. The opening and closing of the on-off valve 85 switches between the start and stop of the treatment liquid delivery to the nozzle 71. A pressure gauge 86 is disposed on the pipe 84. The pressure gauge 86 detects the pressure (discharge pressure) of the treatment liquid delivered to the nozzle 71 and outputs a signal indicating the detected pressure value to the control unit 9.

[0062] Figure 3 It shows Figure 2 Graph showing the movement pattern of the working disk portion 816 of the pump 81. Figure 3 In FIG. 8 , the horizontal axis represents time, and the vertical axis represents the moving speed of the working disk portion 816. The driving portion 87 is driven according to the instruction from the control unit 9 as follows: Figure 3 The movement pattern shown (a curve showing changes in the speed of the working disc portion 816 over time) causes the working disc portion 816 to be displaced axially. Due to the displacement of the working disc portion 816, the volume on the inner side of the bellows 812 changes. Thus, the pump action is performed by radially expanding and contracting the flexible tube 811, and the treatment liquid replenished from the treatment liquid replenishing unit 83 is supplied to the nozzle 71. Since the movement pattern of the working disc portion 816 is closely related to the discharge characteristics of the treatment liquid discharged from the nozzle 71, a pressure waveform representing the change in discharge pressure over time can be obtained according to the movement pattern. It should be noted that the discharge volume (the amount of treatment liquid discharged from the nozzle 71) increases or decreases according to the increase or decrease in the discharge pressure.

[0063] In this embodiment, by adjusting various parameters (acceleration time, constant speed, constant speed time, deceleration time, etc.) that define the movement of the work disk portion 816, an optimization process (adjustment process) is appropriately performed to make the pressure waveform of the treatment liquid discharged from the nozzle 71 consistent with or close to the ideal waveform. This optimization process will be described later.

[0064] like Figure 1 and Figure 2 As shown, a sensor 62 is provided at the nozzle 71 that supplies the processing liquid from the processing liquid supply mechanism 8. The sensor 62 detects the height of the substrate S in the Z direction in a non-contact manner. The sensor 62 can be connected to the control unit 9 by data communication. Based on the detection result of the sensor 62, the control unit 9 measures the distance (separation distance) between the floating substrate S and the upper surface of the coating table 32. The control unit 9 adjusts the coating position of the nozzle 71 based on the positioning mechanism based on the separation distance measured by the sensor 62. It should be noted that the sensor 62 can be an optical sensor or an ultrasonic sensor.

[0065] The coating mechanism 7 includes a nozzle cleaning standby unit 72. The nozzle cleaning standby unit 72 performs prescribed maintenance on the nozzle 71 arranged in the maintenance position. The nozzle cleaning standby unit 72 has a roller 721, a cleaning portion 722 and a roller groove 723. The nozzle cleaning standby unit 72 adjusts the discharge port of the nozzle 71 to a state suitable for coating processing by cleaning the nozzle 71 and forming a liquid accumulation. In addition, in the coating device 1, in order to evaluate the discharge pressure of the applied treatment liquid, in a state where the nozzle 71 is arranged in the maintenance position (simulated coating position), that is, the discharge port of the nozzle 71 is opposite to the outer peripheral surface of the roller 721, the treatment liquid is discharged from the nozzle 71 to the outer peripheral surface of the roller 721. At this time, the treatment liquid discharged from the nozzle 71 can be applied to the moving surface by the rotation of the roller 721. That is, it is possible to simulate the coating of the moving substrate S.

[0066] Discharging the processing liquid from the nozzle 71 onto the surface of the roller 721 may be referred to as "simulated coating," where the processing liquid is discharged onto a portion other than the substrate S. Coating the processing liquid from the nozzle 71 onto the substrate S may be referred to as "actual coating."

[0067] Figure 4 : is a block diagram showing an example of the structure of the control unit 9. The control unit 9 controls the operation of each element of the coating device 1. The control unit 9 is a computer, which includes a calculation unit 91, a storage unit 93 and a user interface 95. The calculation unit 91 is a processor composed of a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). The storage unit 93 is composed of a temporary storage device such as a RAM (Random Access Memory) and a non-temporary auxiliary storage device such as an HHD (Hard Disk Drive) and an SSD (Solid State Drive).

[0068] The user interface 95 includes a display for displaying information to the user and an input device for accepting input operations from the user. As the control unit 9, for example, a desktop computer, a portable computer, or a tablet computer can be used.

[0069] The storage unit 93 stores a program 931. The program 931 is provided via a storage medium M. Specifically, the storage medium M records the program 931 so that it can be read by the control unit 9, which is a computer. The storage medium M may be, for example, a USB (Universal Serial Bus) memory, an optical disk such as a DVD (Digital Versatile Disc), or a magnetic disk.

[0070] The calculation unit 91 functions as a discharge control unit 910 , a discharge pressure measurement unit 911 , a movement control unit 912 , a speed measurement unit 913 , and a discharge control parameter adjustment unit 915 by executing the program 931 .

[0071] The discharge control unit 910 controls the operation (supply operation) of the pump 81 that supplies the processing liquid to the nozzle 71. The discharge control unit 910 controls the supply operation of the pump 81 based on a preset discharge control parameter.

[0072] The discharge pressure measuring unit 911 measures a pressure waveform representing the temporal change in discharge pressure. Specifically, the discharge pressure measuring unit 911 periodically acquires the discharge pressure measured by the pressure gauge 86 at a predetermined sampling period. Thus, the discharge pressure applied to the processing liquid during discharge from the nozzle 71 is acquired and stored in the storage unit 93 as data representing the pressure waveform (discharge data). Discharge data is data representing the relationship between a given moment and the discharge pressure measured at that moment (i.e., the temporal change in discharge pressure).

[0073] The movement control unit 912 controls the operation (movement operation) of the suction travel mechanism 52 that moves the substrate S relative to the nozzle 71 based on preset movement control parameters.

[0074] The speed measuring unit 913 measures the speed of movement of the substrate S via the chuck mechanism 51 and the suction-adjusting mechanism 52. The speed measuring unit 913 measures the movement speed of the substrate S based on the output of the suction-adjusting mechanism 52 (e.g., the output of a rotary encoder). The speed measuring unit 913 stores the acquired speed as speed data in the storage unit 93. The speed data represents the relationship between a time and the movement speed measured at that time (i.e., changes in the movement speed over time).

[0075] The discharge control parameter adjustment unit 915 optimizes the discharge control parameters. The unit evaluates the pressure waveform obtained from the simulated coating and updates the discharge control parameters based on the evaluation results. The unit optimizes the discharge control parameters by repeatedly performing simulated coating, acquiring the pressure waveform, evaluating the pressure waveform, and updating the discharge control parameters.

[0076] In the coating device 1, in order to coat the treatment liquid discharged from the nozzle 71 with a uniform film thickness on the upper surface Sf of the substrate S, it is very important to adjust the discharge speed of the treatment liquid when it is discharged from the nozzle 71, that is, the discharge pressure. Therefore, the discharge control parameters closely related to the pressure waveform are optimized so that the pressure waveform of the discharge pressure is close to the ideal waveform. Specifically, the discharge control parameters to be optimized are set values that regulate the movement of the working disk part 816, which are Figure 3And the 16 set points for pump control indicated below.

[0077] Constant speed V1

[0078] Acceleration time T1: the time it takes to accelerate from a stopped state to a constant speed V1

[0079] Constant speed time T2: the time for which the constant speed V1 is maintained

[0080] Constant speed V2

[0081] Deceleration time T3: the time it takes to decelerate from constant speed V1 to constant speed V2

[0082] Constant speed time T4: time for which the constant speed V2 is maintained

[0083] Constant speed V3

[0084] Acceleration time T5: time to accelerate from constant speed V2 to constant speed V3

[0085] Constant speed time T6: time for maintaining constant speed V3

[0086] Constant speed V4

[0087] Deceleration time T7: the time to decelerate from constant speed V3 to constant speed V4

[0088] Constant speed time T8: The time for maintaining constant speed V4

[0089] Constant speed V5

[0090] Acceleration time T9: Time to accelerate from constant speed V4 to constant speed V5

[0091] Constant speed time T10: the time for maintaining constant speed V5

[0092] Deceleration time T11: The time it takes to decelerate from a constant speed V5 to a stop

[0093] The 16 discharge control parameters described above correspond to control variables for controlling the operation (supply operation) of pump 81 that supplies the treatment liquid to nozzle 71. It should be noted that there is no particular limitation on the type and number of discharge control parameters and they can be set arbitrarily as long as they are control variables for controlling the supply operation of pump 81.

[0094] <Adjustment of discharge control parameters>

[0095] Figure 5 This is a flowchart showing the adjustment process of the discharge control parameters. Figure 5The adjustment process shown is performed when the process recipe is changed or when there is an input instruction from the user. Specifically, the process recipe includes process steps or process content (type of process liquid, type of substrate, supply amount of process liquid).

[0096] Figure 5 The adjustment process shown includes a preliminary adjustment phase (steps S1 to S4), in which the discharge control parameters are adjusted before actual coating; and an actual coating phase (steps S5 and onward), in which the substrate S is actually coated according to the discharge control parameters adjusted in the preliminary adjustment phase. Furthermore, the actual coating phase includes a readjustment phase (steps S7 to S9), in which the discharge control parameters are readjusted based on the measured pressure waveform. During the preliminary adjustment and readjustment phases, as described below, the discharge control parameters are updated based on the pressure waveform obtained during the simulated coating.

[0097] <Preliminary Adjustment Phase>

[0098] During the pre-adjustment phase, the discharge control parameter adjustment unit 915 first sets the discharge control parameters to predetermined initial values (step S1). The initial values may be arbitrary values or values set based on a predetermined algorithm. Furthermore, the discharge control parameter adjustment unit 915 may accept input of initial values from the user and store the received initial values in the storage unit 93.

[0099] After setting the discharge control parameters in step S1, the coating device 1 acquires the pressure waveform while performing simulated coating (step S2). Specifically, the nozzle 71 is moved to a specified maintenance position (a position opposite to the roller 721). Thereafter, the control unit 9 controls the pump 81 according to the control parameters set in step S1 to discharge the processing liquid from the nozzle 71 to the roller 721. In addition, during the simulated coating, the discharge pressure measuring unit 911 samples the discharge pressure measured by the pressure gauge 86 and acquires the data of the pressure waveform. The pressure waveform acquired in step S2 is an example of a "second simulated coating pressure waveform". Step S2 is an example of a "second simulated coating process" and a "third acquisition process".

[0100] After obtaining the pressure waveform of the simulated coating in step S2, the simulated coating pressure waveform is evaluated (step S3). As an example of the evaluation method, the ejection control parameter adjustment unit 915 determines whether the pressure waveform obtained in step S2 is consistent with the first ideal waveform Wt1 ( Figure 6 Step S3 is an example of a "third evaluation step".

[0101] It should be noted that in step S3, the user can evaluate the pressure waveform. In this case, in step S3, the control unit 9 can display the pressure waveform and the first ideal waveform Wt1 on the display. Furthermore, the control unit 9 can display the aforementioned deviation on the display. This allows the user to appropriately assist in their evaluation by displaying various information on the display. Furthermore, the control unit 9 can receive evaluation results from the user via an input device and store the input evaluation results in the storage unit 93.

[0102] When the simulated coating pressure waveform is evaluated to be identical to the first ideal waveform Wt1 in step S3 (for example, when the deviation is within the allowable range, "Yes" in step S3), the coating apparatus 1 ends the preliminary adjustment stage and proceeds to the actual coating stage after step S5.

[0103] If the pressure waveform is evaluated as being different from the first ideal waveform Wt1 by step S3 (for example, if the deviation exceeds the allowable range, "No" in step S3), the coating device 1 updates the discharge control parameters (step S4). Specifically, the discharge control parameter adjustment unit 915 updates the discharge control parameters based on the evaluation result of step S3 so that the pressure waveform during the simulated coating becomes the first ideal waveform Wt1. The algorithm for updating the discharge control parameters can be arbitrarily selected from, for example, Bayesian optimization, genetic algorithm, gradient algorithm, linear programming method, etc. Step S4 is an example of a "second updating process."

[0104] Note that, as described in Patent Document 1, the discharge control parameters can be updated using a learned model that has learned the relationship between the amount of change in the discharge control parameters and the deviation. A neural network can be used as the learning model.

[0105] In addition, in step S4 , the user may be asked to update the discharge control parameters. In this case, the control unit 9 may receive input of new discharge control parameters via the input device and store the received discharge control parameters in the storage unit 93 .

[0106] After updating the discharge control parameters in step S4, the coating device 1 returns to step S2 and performs the simulated coating again. The coating device 1 repeats steps S2 through S4 until the pressure waveform obtained from the simulated coating reaches the ideal waveform. Thus, the discharge control parameters are adjusted to appropriate values.

[0107] <Actual coating stage>

[0108] In the actual coating stage, first, the coating device 1 performs actual coating based on the discharge control parameters adjusted in the pre-adjustment stage, and obtains the pressure waveform (step S5). Specifically, the processing liquid supply mechanism 8 moves the nozzle 71 to the coating position. Afterwards, the control unit 9 controls the moving mechanism 5 to move the substrate S in the prescribed conveying direction DT, while driving the pump 81 according to the discharge control parameters, so that the processing liquid is discharged from the nozzle 71 to the substrate S. In addition, during the actual coating, the discharge pressure measuring unit 911 obtains pressure waveform data by sampling the discharge pressure measured by the pressure gauge 86. Hereinafter, the pressure waveform obtained in step S5 will be referred to as the "actual coating pressure waveform". Step S5 is an example of the "actual coating process" and the "first acquisition process".

[0109] After obtaining the actual coating pressure waveform in step S5, the actual coating pressure waveform is evaluated (step S6). The evaluation method for the actual coating pressure waveform can be the same as the pressure waveform evaluation method in step S3. In other words, the discharge control parameter adjustment unit 915 can determine whether the deviation between the actual coating pressure waveform obtained in step S5 and the first ideal waveform Wt1 exceeds a specified allowable range. Step S6 is an example of a "first evaluation step."

[0110] It should be noted that in step S6, the user can also evaluate the actual coating pressure waveform. In this case, in step S6, the control unit 9 can display the actual coating pressure waveform and the first ideal waveform Wt1 on the display. Furthermore, the control unit 9 can display the aforementioned deviation amount on the display. This allows the user to appropriately assist in evaluation by displaying various information on the display. Furthermore, the control unit 9 can receive evaluation results from the user via an input device and store the input evaluation results in the storage unit 93.

[0111] If the actual coating pressure waveform is evaluated as being identical to the first ideal waveform Wt1 in step S6 (for example, if the deviation is within the allowable range, "Yes" in step S6), the coating device 1 ends the adjustment process of the discharge control parameters. That is, in subsequent actual coating, the discharge control parameters used in step S5 are used. On the other hand, if the actual coating pressure waveform is evaluated as being inconsistent with the first ideal waveform Wt1 in step S6 (for example, if the deviation exceeds the allowable range, "No" in step S6), the coating device 1 determines that the discharge control parameters need to be readjusted and executes the readjustment phase from step S7 to step S9.

[0112] Readjustment Phase

[0113] In the readjustment phase, first, the discharge control parameters are updated (step S7). Specifically, the discharge control parameter adjustment unit 915 makes the pressure waveform during the simulated coating process become the second ideal waveform Wt2 ( Figure 6 The discharge control parameters are updated by the method of (refer to) . The algorithm for updating the discharge control parameters can be arbitrarily selected from, for example, Bayesian optimization, genetic algorithm, gradient algorithm, linear programming method, etc. Step S7 is an example of the "first updating step".

[0114] Note that, as described in Patent Document 1, the discharge control parameters can be updated by using a learned model that has learned the relationship between the amount of change in the discharge control parameters and the deviation. A neural network can be used as the learning model.

[0115] Alternatively, the user may update the control parameters in step S7 . In this case, the discharge control parameter adjustment unit 915 may receive input of new discharge control parameters from the user via an input device and store the received discharge control parameters in the storage unit 93 .

[0116] Figure 6 : is a diagram showing an example of setting the second ideal waveform Wt2. The second ideal waveform Wt2 is generated, for example, by the ejection control parameter adjustment unit 915 and stored in the storage unit 93. The second ideal waveform Wt2 has a shape different from the first ideal waveform Wt1. Specifically, the second ideal waveform Wt2 has a shape obtained by deforming the first ideal waveform Wt1 based on the difference (deviation) between the actual coating pressure waveform Wr1 and the first ideal waveform Wt1. In more detail, the second ideal waveform Wt2 has a shape obtained by subtracting the above difference from the first ideal waveform Wt1. It should be noted that the shape of the second ideal waveform Wt2 is not limited to Figure 6 The shapes shown can be set appropriately.

[0117] Return to Figure 5 After the discharge control parameters are updated in step S7, the coating device 1 performs simulated coating according to the updated discharge control parameters (step S8). Step S8 is an example of a "first simulated coating process" and a "second acquisition process". When the nozzle 71 is located at the coating position above the coating table 32, the coating mechanism 7 moves the nozzle 71 to the maintenance position. Thereafter, the processing liquid is discharged from the nozzle 71 toward the rotating roller 721. During the simulated coating, the discharge pressure measuring unit 911 acquires a pressure waveform by sampling the discharge pressure measured by the pressure gauge 86. The pressure waveform acquired in step S8 is an example of a "first simulated coating pressure waveform".

[0118] After obtaining the pressure waveform in step S8, the simulated coating pressure waveform is evaluated (step S9). The pressure waveform evaluation method can be the same as the pressure waveform evaluation method in step S3. However, in step S9, the second ideal waveform Wt2 can be used instead of the first ideal waveform Wt1. Specifically, the discharge control parameter adjustment unit 915 can determine whether the deviation between the pressure waveform obtained in step S8 and the second ideal waveform Wt2 exceeds a prescribed allowable range. Step S8 is an example of a "second evaluation process."

[0119] It should be noted that in step S9, the user can also evaluate the pressure waveform. In this case, in step S6, the control unit 9 can display the pressure waveform and the second ideal waveform Wt2 on the display. Furthermore, the control unit 9 can also display the aforementioned deviation on the display. This allows the user to appropriately assist in their evaluation by displaying various information on the display. Furthermore, the control unit 9 can receive evaluation results from the user via an input device and store the input evaluation results in the storage unit 93.

[0120] If the pressure waveform of the simulated coating is evaluated as being different from the second ideal waveform Wt2 by step S9 (for example, if the deviation exceeds the allowable range, "No" in step S9), the coating device 1 performs step S7 (updating the discharge control parameters) again. On the other hand, if the pressure waveform of the simulated coating is evaluated as being the same as the second ideal waveform Wt2 by step S9, the coating device 1 ends the readjustment phase and performs actual coating in step S5. In this way, the coating device 1 repeatedly performs steps S7 to S9 until it is evaluated that the pressure waveform obtained by the simulated coating is the same as the second ideal waveform Wt2. As a result, the discharge control parameters are adjusted again.

[0121] Effects

[0122] If the actual coating pressure waveform is determined to be less than ideal in step S6, the discharge control parameters are readjusted based on the pressure waveform obtained during the simulated coating (step S8). This allows the discharge control parameters to be readjusted while suppressing the consumption of substrates S. By suppressing the consumption of substrates S, the environmental impact can be reduced.

[0123] Furthermore, during the readjustment phase, the second ideal waveform Wt2, which serves as the basis for evaluation, is set to the shape of the first ideal waveform Wt1 deformed according to the difference between the actual coating pressure waveform Wr1 and the first ideal waveform Wt1. This effectively readjusts the discharge control parameters so that the pressure waveform during actual coating matches the first ideal waveform Wt1.

[0124] Furthermore, by pre-adjusting the discharge control parameters for actual coating based on the pressure waveform obtained in the simulated coating of step S2 , consumption of the substrate S can be further suppressed.

[0125] <2. Modifications>

[0126] Although the embodiments have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible.

[0127] For example, in the above embodiment, the simulated coating is performed by discharging the treatment liquid onto the roller 721. However, the treatment liquid may be discharged to a location other than the roller 721. For example, the treatment liquid may be discharged into a container such as the roller groove 723 that can receive the treatment liquid discharged from the nozzle 71.

[0128] While the present invention has been described in detail above, the above description is in all respects merely illustrative and the present invention is not limited thereto. It should be understood that numerous variations not illustrated herein are possible without departing from the scope of the present invention. The various components described in the above embodiments and variations may be appropriately combined or omitted as long as no inconsistency arises.

Claims

1. A coating method for coating a substrate with a treatment liquid, wherein: include: an actual coating step of moving the substrate relative to the nozzle and discharging the processing liquid from the nozzle onto the substrate according to pre-set discharge control parameters; a first acquisition step of acquiring an actual coating pressure waveform indicating a temporal change in the discharge pressure of the nozzle in the actual coating step; A first evaluation step is to evaluate the actual coating pressure waveform; as well as a readjustment step of readjusting the discharge control parameter based on the evaluation result of the first evaluation step; The readjustment process includes: a first simulated coating step of performing simulated coating of discharging the processing liquid from the nozzle to a portion other than the substrate according to the discharge control parameter; a second acquisition step of acquiring a first simulated coating pressure waveform indicating a change in the discharge pressure over time in the first simulated coating step; a second evaluation step of evaluating the first simulated coating pressure waveform; and The first updating step updates the discharge control parameter based on the evaluation result of the second evaluating step.

2. The coating method according to claim 1, wherein The first evaluation step includes the step of performing evaluation based on the deviation amount between the actual coating pressure waveform and the first ideal waveform, The second evaluation step includes performing evaluation based on an amount of deviation between the first simulated application pressure waveform and a second ideal waveform having a shape different from the first ideal waveform.

3. The coating method according to claim 2, wherein The second ideal waveform has a shape obtained by deforming the first ideal waveform according to a difference between the actual application pressure waveform and the first ideal waveform.

4. The coating method according to any one of claims 1 to 3, wherein The process also includes: a pre-adjustment process, in which the discharge control parameters are adjusted before the actual coating process. The pre-adjustment process includes: a second simulated coating step, performing the simulated coating according to the pre-set discharge control parameters; a third acquisition step of acquiring a second simulated coating pressure waveform indicating a change in the discharge pressure over time in the second simulated coating step; a third evaluation step of evaluating the second simulated coating pressure waveform; and a second updating step of updating the discharge control parameter based on the evaluation result of the third evaluation step; In the actual coating step, the actual coating is performed based on the discharge control parameters adjusted in the preliminary adjustment step.

5. A storage medium having a computer-readable program recorded thereon, wherein: The program causes the computer to execute the coating method according to any one of claims 1 to 3.

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