Substrate processing method and substrate processing apparatus

Abstract

To provide a technology capable of checking the operation of a drive portion in a chamber with higher accuracy.SOLUTION: A substrate processing method includes a processing step, an imaging step, a synchronization step, and a calculation step. In the processing step, the control unit measures time while outputting a control signal to at least one drive unit of the processing unit to cause the processing unit to process a substrate carried into a chamber. In the imaging step, which is performed during at least a portion of the processing step, a camera images the interior of the chamber and generates image data. In the synchronization step, a synchronization process is performed to reduce the difference between the current time measured by the control unit and the current time measured by the camera. In the calculation step, a change in an event in the chamber is detected on the basis of the image data, the time of occurrence of the event change is calculated on the basis of the image capture time of the image data, and the time difference between the output time of the control signal and the time of occurrence of the event change is found on the basis of the synchronized time.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present disclosure relates to a substrate processing method and a substrate processing apparatus.

Background Art

[0002] Conventionally, a substrate processing apparatus that supplies a processing liquid to a substrate to process the substrate has been proposed (for example, Patent Document 1). In Patent Document 1, the substrate processing apparatus includes a chamber, a spin chuck, a nozzle, a supply pipe, a valve, a camera, and a control unit. The spin chuck is provided in the chamber and rotates the substrate around a vertical rotation axis passing through the center of the substrate while holding the substrate in a horizontal posture. The nozzle is provided in the chamber and discharges the processing liquid toward the upper surface of the rotating substrate. Specifically, when the control unit opens the valve, the processing liquid is supplied to the nozzle through the supply pipe and discharged from the nozzle toward the upper surface of the substrate. The processing liquid that adheres to the upper surface of the substrate receives the centrifugal force due to the rotation of the substrate and flows radially outward, and scatters outward from the periphery of the substrate. When the processing liquid acts on the upper surface of the substrate, processing corresponding to the processing liquid is performed on the substrate.

[0003] The camera images the inside of the chamber and generates captured image data. The control unit monitors the object to be monitored inside the chamber based on the captured image data.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The control unit can open the valve by outputting a control signal to the valve. Since the control unit has a function of measuring time, it can grasp the output time of the control signal. On the other hand, based on the captured image data, the control unit can detect, for example, a change in the discharge state of the processing liquid from the nozzle, and can obtain the change time of the discharge state based on the imaging time of the captured image data. However, if there is a deviation between the clock of the camera and the control clock of the control unit, the output time of the control signal and the change time of the discharge state cannot be accurately measured on the same time axis. In this case, there is a risk that the control unit cannot monitor appropriately.

[0006] Therefore, an object of the present disclosure is to provide a technique capable of confirming the operation of a drive unit in a chamber with higher accuracy.

Means for Solving the Problems

[0007] A first aspect is a substrate processing method, including a processing step in which a control unit measures time and outputs a control signal to at least one drive unit of a processing unit to cause the processing unit to perform processing on a substrate carried into a chamber; an imaging step that is executed during at least a part of the processing step, in which a camera images the inside of the chamber to generate image data; a synchronization step of performing a synchronization process for reducing a difference between the current time measured by the control unit and the current time measured by the camera; and a calculation step of detecting an event change in the chamber based on the image data, calculating the occurrence time of the event change based on the imaging time of the image data, and obtaining a time difference between the output time of the control signal and the occurrence time of the event change based on the synchronized time.

[0008] A second aspect is the substrate processing method according to the first aspect. In the processing step, the control unit outputs a movement command as the control signal to the nozzle movement drive unit to move a nozzle that discharges a processing liquid toward the main surface of the substrate. In the calculation step, the movement of the nozzle is detected based on the image data, and a delay time, which is the time difference from the output time of the movement command to the movement time of the nozzle, is obtained based on synchronized time.

[0009] A third aspect is the substrate processing method according to the first or second aspect. In the processing step, the control unit outputs an open command or a close command as the control signal to a supply valve provided in a supply pipe connected to a nozzle that discharges a processing liquid toward the main surface of the substrate. In the calculation step, a change in the discharge state of the processing liquid from the nozzle is detected based on the image data, and a delay time, which is the time difference from the output time of the control signal to the change time of the discharge state, is obtained based on synchronized time.

[0010] A fourth aspect is the substrate processing method according to the third aspect. In the processing step, after the control unit outputs the open command to the supply valve to discharge the processing liquid from the nozzle, the control unit outputs the close command to the supply valve to stop the discharge of the processing liquid from the nozzle. In the calculation step, the start of the discharge of the processing liquid from the nozzle in response to the open command is detected based on the image data, and the stop of the discharge of the processing liquid from the nozzle in response to the close command is detected based on the image data, and a supply time from the start time of the discharge of the processing liquid to the stop time of the discharge is obtained.

[0011] A fifth aspect is the substrate processing method according to the third or fourth aspect. In the calculation step, a change in the fluctuation of the processing liquid at the liquid landing position of the processing liquid on the main surface of the substrate is detected as a change in the discharge state of the processing liquid based on the image data.

[0012] A sixth aspect is a substrate processing method according to any one of the first to fifth aspects, wherein in the processing step, the control unit outputs a speed change command as the control signal to a rotation drive unit that rotates the substrate while discharging a processing liquid from a nozzle toward the main surface of the substrate, and in the calculation step, a change in the fluctuation of the processing liquid on the main surface of the substrate at a position radially outside the liquid landing position of the processing liquid is detected as a change in the rotation speed of the substrate based on the image data.

[0013] A seventh aspect is a substrate processing method according to any one of the first to sixth aspects, wherein in the processing step, the control unit outputs the control signal to a displacement drive unit that displaces the position of a displacement target in the chamber, outputs an open command or a close command as the control signal to a supply valve provided in a supply pipe connected to a nozzle that discharges a processing liquid onto the main surface of the substrate, in the calculation step, a change in the discharge state of the processing liquid from the nozzle is detected based on the image data, and a time difference between the output time of the control signal to the displacement drive unit and the change time of the discharge state of the processing liquid is obtained based on synchronized times.

[0014] An eighth aspect is a substrate processing method according to the seventh aspect, wherein in the processing step, the control unit outputs the close command to the supply valve and outputs a speed change command as the control signal to a rotation drive unit, which is the displacement drive unit that rotates the substrate, in the calculation step, the stop of the discharge of the processing liquid from the nozzle is detected based on the image data, and a time difference between the output time of the speed change command and the stop time of the discharge of the processing liquid is obtained based on synchronized times.

[0015] A ninth aspect is a substrate processing method according to any one of the first to eighth aspects, wherein in the processing step, the control unit outputs the control signal to a displacement driving unit that displaces the position of the object to be displaced in the chamber, and in the synchronization step, the control unit detects the start of the position change of the object to be displaced in the chamber based on the image data, calculates a displacement start time when the position of the object to be displaced starts to change based on the imaging time of the image data, and performs the synchronization process based on the output time of the control signal and the displacement start time.

[0016] A tenth aspect is a substrate processing method according to any one of the first to ninth aspects, wherein for each of the plurality of substrates, the processing step, the imaging step, the synchronization step, and the calculation step are performed, and time-series data indicating the change over time of the time difference for the plurality of substrates is generated.

[0017] An eleventh aspect is a substrate processing method according to any one of the first to tenth aspects, wherein for each of the plurality of processing units, the processing step, the imaging step, the synchronization step, and the calculation step are performed, and inter-device data indicating the variation of the time difference between the plurality of processing units is generated.

[0018] A twelfth aspect is a substrate processing apparatus, comprising a chamber, a camera that images the inside of the chamber to generate image data, a driving unit for processing a substrate carried into the chamber, and a control unit that outputs a control signal to the driving unit to cause the driving unit to perform processing on the substrate carried into the chamber. The control unit performs a synchronization process to reduce the difference between the current time measured by the control unit and the current time measured by the camera, detects an event change in the chamber based on the image data, calculates the occurrence time of the event change based on the imaging time of the image data, and obtains the time difference between the output time of the control signal and the occurrence time of the event change based on the synchronized time.

Advantages of the Invention

[0019] According to the 1st and 12th aspects, the time difference between the output time of the control signal and the occurrence time of the event change can be obtained with high accuracy.

[0020] According to the 2nd aspect, the delay time for the nozzle movement drive unit can be obtained with high accuracy.

[0021] According to the 3rd aspect, the delay time for the change in the ejection state can be obtained with high accuracy.

[0022] According to the 4th aspect, the supply time can be obtained.

[0023] According to the 5th aspect, based on the image data, the change in the ejection state can be detected with high accuracy.

[0024] According to the 6th aspect, based on the image data, the change in the rotation speed can be detected.

[0025] According to the 7th aspect, since the displacement drive unit has high responsiveness, the displacement start time when the position of the displacement target starts to change substantially coincides with the output time of the control signal to the displacement drive unit. Therefore, the time difference between the displacement start time and the change time of the ejection state can be obtained with high accuracy.

[0026] According to the 8th aspect, the time difference between the change start time of the rotation speed of the substrate and the ejection stop time of the processing liquid can be obtained more simply and with higher accuracy.

[0027] According to the 9th aspect, since a reset signal to the camera is unnecessary, the function of the camera can be simplified.

[0028] According to the 10th aspect, the change over time of the drive unit can be confirmed.

[0029] According to the 11th aspect, the variation of the drive unit among a plurality of processing units can be confirmed.

Brief Description of the Drawings

[0030]

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Embodiments for Carrying Out the Invention

[0031] Hereinafter, embodiments will be described in detail with reference to the drawings. In the drawings, for the purpose of easy understanding, the dimensions and numbers of each part are exaggerated or simplified as necessary. Also, parts having the same configuration and function are denoted by the same reference numerals, and duplicate explanations are omitted in the following description.

[0032] In the following descriptions, the same reference numerals are used to denote the same components in the drawings, and their names and functions are also assumed to be the same. Therefore, detailed descriptions thereof may be omitted to avoid duplication.

[0033] In the following descriptions, even if ordinal numbers such as "first" or "second" are used, these terms are used for convenience to facilitate understanding of the content of the embodiments, and are not limited to the order that may be caused by these ordinal numbers.

[0034] When expressions indicating relative or absolute positional relationships (such as "in one direction", "along one direction", "parallel", "orthogonal", "center", "concentric", "coaxial", etc.) are used, unless otherwise specified, the expression not only represents the positional relationship precisely, but also represents a state in which the angle or distance is displaced within a tolerance or a range where the same function can be obtained. When an expression indicating an equal state (such as "identical", "equal", "homogeneous", etc.) is used, unless otherwise specified, the expression not only represents a quantitatively precise equal state, but also represents a state in which there is a difference within a tolerance or a range where the same function can be obtained. When an expression indicating a shape (such as "quadrilateral shape" or "cylindrical shape") is used, unless otherwise specified, the expression not only represents the shape geometrically precisely, but also represents a shape having, for example, unevenness or chamfers within a range where the same effect can be obtained. When an expression such as "comprises", "has", "includes", or "owns" is used for a component, the expression is not an exclusive expression excluding the existence of other components. When an expression such as "at least any one of A, B, and C" is used, the expression includes only A, only B, only C, any two of A, B, and C, and all of A, B, and C.

[0035] <Overall Configuration of Substrate Processing Apparatus> FIG. 1 is a plan view schematically showing an example of the configuration of a substrate processing apparatus 100. The substrate processing apparatus 100 is a single-wafer processing apparatus that processes substrates W one by one.

[0036] The substrate W is, for example, a semiconductor wafer, a substrate for a liquid crystal display, a substrate for an organic EL (Electroluminescence), a substrate for an FPD (Flat Panel Display), a substrate for an optical display, a substrate for a magnetic disk, a substrate for an optical disk, a substrate for a magneto-optical disk, a substrate for a photomask, or a substrate for a solar cell. The substrate W has a thin flat plate shape. Hereinafter, it is assumed that the substrate W is a semiconductor wafer. The substrate W has, for example, a disc shape. The diameter of the substrate W is, for example, about 300 mm, and the film thickness of the substrate W is, for example, about 0.5 mm or more and about 3 mm or less.

[0037] In the example of FIG. 1, the substrate processing apparatus 100 includes an index block 110, a processing block 120, and a control unit 90. The processing block 120 is a part mainly for processing the substrate W, and the index block 110 is a part mainly for transporting the substrate W between the outside of the substrate processing apparatus 100 and the processing block 120.

[0038] The index block 110 includes a load port 111 and a first transfer unit 112. A substrate container (hereinafter referred to as a carrier) C carried in from the outside is placed on the load port 111. A plurality of substrates W are accommodated in the carrier C. For example, the plurality of substrates W are accommodated in the carrier C in a state of being arranged at intervals in the vertical direction.

[0039] The first transfer unit 112 is a transfer robot that takes out an unprocessed substrate W from the carrier C placed on each load port 111 and transfers the substrate W to the processing block 120. The first transfer unit 112 may also be called an index robot. The processing block 120 processes the substrate W. Further, the first transfer unit 112 receives the processed substrate W from the processing block 120 and transfers the substrate W to the carrier C of the load port 111.

[0040] In the example of FIG. 1, the processing block 120 includes a plurality of processing units 1 and a second transfer unit 122. The second transfer unit 122 is a transfer robot that transfers the substrate W between the first transfer unit 112 and the plurality of processing units 1. The second transfer unit 122 receives the unprocessed substrate W from the first transfer unit 112, for example, via the placement unit 123, and transfers the substrate W to the processing unit 1. The processing unit 1 processes the substrate W. The configuration of the processing unit 1 will be described later. The second transfer unit 122 takes out the processed substrate W from the processing unit 1 and transfers the substrate W to the first transfer unit 112, for example, via the placement unit 123.

[0041] The second transfer unit 122 may transfer the substrate W between the plurality of processing units 1 as necessary. For example, the second transfer unit 122 may transfer the substrate W processed by a certain processing unit 1 to another processing unit 1 and transfer the substrate W processed by the other processing unit 1 to the first transfer unit 112.

[0042] In the example of FIG. 1, the plurality of processing units 1 are provided so as to surround the second transfer unit 122 in a plan view. This second transfer unit 122 may also be called a center robot. In the example of FIG. 1, four processing units 1 surround the second transfer unit 122. At each position in the plan view where each processing unit 1 is provided, the plurality of processing units 1 may be stacked in the vertical direction. That is, a plurality (four in the figure) of towers TW composed of a plurality of processing units 1 stacked in the vertical direction may be provided so as to surround the second transfer unit 122 in a plan view.

[0043] The control unit 90 comprehensively controls the substrate processing apparatus 100. Specifically, the control unit 90 controls the first transfer unit 112, the second transfer unit 122, and the processing unit 1. FIG. 2 is a block diagram schematically showing an example of the configuration of the control unit 90. The control unit 90 is an electronic circuit and has, for example, a data processing unit 91 and a storage unit 92. The data processing unit 91 may be an arithmetic processing device such as a CPU (Central Processor Unit). The storage unit 92 may have a non-temporary storage unit (for example, ROM (Read Only Memory)) 921 and a temporary storage unit (for example, RAM (Random Access Memory)) 922. A program that defines the processing executed by the control unit 90 may be stored in the non-temporary storage unit 921. By the data processing unit 91 executing this program, the control unit 90 can execute the processing defined in the program. Of course, part or all of the processing executed by the control unit 90 may be executed by hardware such as a dedicated logic circuit.

[0044] In the example of FIG. 2, a storage unit 94 is connected to the control unit 90. The storage unit 94 is, for example, a hard disk or a non-temporary memory. In the example of FIG. 2, recipe information D1 is stored in the storage unit 94. The recipe information D1 will be described later.

[0045] The control unit 90 also has a function of measuring time. The control unit 90 includes, for example, a clock generator (clock generation circuit: not shown) that generates a control clock, and measures time based on the control clock.

[0046] In the example of FIG. 1, a user interface 95 is connected to the control unit 90. The user interface 95 includes an input device and a notification unit. The input device is a device that receives user input, and is, for example, an input device such as a mouse and a keyboard. The notification unit is a device that conveys information to the user and includes at least one of, for example, a display such as a liquid crystal display and a sound output unit such as a speaker.

[0047] <Overview of the Processing Unit> FIG. 3 is a longitudinal sectional view schematically showing an example of the configuration of the processing unit 1. Note that not all the processing units 1 belonging to the substrate processing apparatus 100 need to have the configuration illustrated in FIG. 3. It is sufficient that at least one processing unit 1 has the configuration illustrated in FIG. 3. The processing unit 1 includes a chamber 10, various drive units for processing the substrate W, and a camera 5. As will be described in detail later, the control unit 90 outputs a control signal to each drive unit of the processing unit 1, and each drive unit operates appropriately in response to the control signal, whereby the processing unit 1 can appropriately process the substrate W. Further, in the present embodiment, as will be described in detail later, the control unit 90 monitors the inside of the chamber 10 based on the image data captured by the camera 5. Hereinafter, first, the configuration of the processing unit 1 will be described, and then each drive unit will be described.

[0048] The chamber 10 has an internal space. The internal space corresponds to a processing space for processing the substrate W. The chamber 10 is provided with an openable / closable carry-in / out port (not shown). The second transfer unit 122 transfers the unprocessed substrate W into the chamber 10 through the carry-in / out port, and transfers the processed substrate W out of the chamber 10 through the carry-in / out port.

[0049] In the example of FIG. 3, the processing unit 1 further includes a substrate holding unit 2, a discharge unit 3, a guard 7, and a guard lifting drive unit 8. The substrate holding unit 2 is provided inside the chamber 10 and rotates the substrate W around the rotation axis Q1 while holding the substrate W in a horizontal posture. The horizontal posture here means a posture in which the thickness direction of the substrate W is along the vertical direction. The rotation axis Q1 is an axis passing through the center of the substrate W and along the vertical direction. Such a substrate holding unit 2 can also be called a spin chuck.

[0050] In the example of FIG. 3, the substrate holding unit 2 includes a spin base 21, chuck pins 22, and a rotation driving unit 23. The spin base 21 has a plate-like shape (for example, a disk shape), and is provided in a posture in which its thickness direction is along the vertical direction. A plurality of chuck pins 22 are provided on the upper surface of the spin base 21. The plurality of chuck pins 22 are provided at equal intervals along the circumferential direction about the rotation axis Q1. The plurality of chuck pins 22 are provided so as to be displaceable between a holding position and a release position described below. The holding position is a position where the chuck pin 22 abuts against the peripheral edge of the substrate W. When the plurality of chuck pins 22 stop at their respective holding positions, the plurality of chuck pins 22 hold the substrate W. In FIG. 3, the chuck pins 22 stopped at the holding positions are shown. The release position is a position where each chuck pin 22 is separated from the substrate W. When the plurality of chuck pins 22 stop at their respective release positions, the holding of the substrate W by the plurality of chuck pins 22 is released. The substrate holding unit 2 also includes a pin driving unit (not shown) that displaces the chuck pins 22. The pin driving unit includes a driving source such as a motor or an air cylinder, for example, and is controlled by the control unit 90.

[0051] The rotation driving unit 23 includes a shaft 231 and a motor 232. The upper end of the shaft 231 is connected to the lower surface of the spin base 21, and the shaft 231 extends along the rotation axis Q1 from the lower surface of the spin base 21. The motor 232 is controlled by the control unit 90 and rotates the shaft 231 around the rotation axis Q1. Thereby, the spin base 21, the chuck pins 22, and the substrate W rotate integrally around the rotation axis Q1. This rotation driving unit 23 corresponds to an example of a driving unit for performing processing on the substrate W.

[0052] Note that the substrate holding unit 2 does not necessarily have to have the chuck pins 22. For example, the substrate holding unit 2 may hold the substrate W by a chuck method such as a vacuum chuck, an electrostatic chuck, and a Bernoulli chuck.

[0053] The discharging unit 3 discharges a processing fluid toward the main surface of the substrate W held by the substrate holding unit 2. The processing fluid is, for example, a gas or a liquid (hereinafter referred to as a processing liquid), and as a specific example, it is a processing liquid. In the example of FIG. 3, the discharging unit 3 includes a nozzle 31, a supply pipe 32, a supply valve 33, and a flow rate adjustment valve 34. The nozzle 31 is provided in the chamber 10. In the example of FIG. 3, the nozzle 31 is provided vertically above the substrate W held by the substrate holding unit 2 and discharges the processing liquid toward the upper surface of the substrate W. The nozzle 31 may be a nozzle that discharges the processing liquid in a continuous flow state, or may be a mist nozzle or a spray nozzle that discharges the processing liquid in a droplet state. Here, as an example, the nozzle 31 is a nozzle that discharges the processing liquid in a continuous flow state.

[0054] The processing liquid may be a coating liquid, a chemical solution, a rinsing liquid, or an antistatic liquid. The coating liquid is a solvent containing the components of the thin film to be formed on the main surface of the substrate W. The coating liquid may be a resist liquid. The chemical solution may be a cleaning liquid for removing foreign substances on the main surface of the substrate W, or an etching liquid for removing the target film. As the chemical solution, for example, hydrofluoric acid and nitric acid and water are mixed to obtain hydrofluoric acid and nitric acid, hydrofluoric acid and hydrogen peroxide and water are mixed to obtain an aqueous solution of hydrofluoric acid and hydrogen peroxide (FPM), tetramethylammonium hydroxide (TMAH), a mixed solution of sulfuric acid and hydrogen peroxide solution (SPM), aqueous ammonia, and a mixed solution of ammonia, hydrogen peroxide, and water (SC-1), etc. can be applied. Note that the chemical solution may be a single liquid instead of a mixed solution. For example, single liquids such as hydrofluoric acid (HF), hydrogen peroxide solution, and sulfuric acid can be applied as the chemical solution. The rinsing liquid may be pure water (that is, deionized water), or an organic solvent such as isopropyl alcohol that is more volatile than pure water. The antistatic liquid is a liquid for removing the charge of the substrate W, and may be carbonated water. Carbonated water may be used as a rinsing liquid.

[0055] In the example of FIG. 3, the downstream end of the supply pipe 32 is connected to the nozzle 31. The upstream end of the supply pipe 32 is connected to a processing liquid supply source. The processing liquid supply source has a tank (not shown) for storing the processing liquid and supplies the processing liquid to the upstream end of the supply pipe 32. In the example of FIG. 3, a supply valve 33 and a flow rate adjustment valve 34 are provided in the supply pipe 32. The supply valve 33 switches the opening and closing of the supply pipe 32, and the flow rate adjustment valve 34 adjusts the flow rate of the processing liquid flowing through the supply pipe 32. The flow rate adjustment valve 34 may be a mass flow controller. These valves are controlled by the control unit 90. Each of the supply valve 33 and the flow rate adjustment valve 34 corresponds to an example of a driving unit for processing the substrate W.

[0056] The processing unit 1 may include a plurality of nozzles 31 corresponding to a plurality of types of processing liquids respectively. In the example of FIG. 3, nozzle 31A and nozzle 31B are shown as the nozzles 31. The nozzle 31A is, for example, a nozzle for a coating liquid, and the nozzle 31B is, for example, a nozzle for pure water. Hereinafter, an "A" may be appended to the end of the reference numerals of the supply pipe 32, the supply valve 33, and the flow rate adjustment valve 34 corresponding to the nozzle 31A, and a "B" may be appended to the end of the reference numerals of the supply pipe 32, the supply valve 33, and the flow rate adjustment valve 34 corresponding to the nozzle 31B.

[0057] In the example of FIG. 3, the processing unit 1 includes a nozzle movement driving unit 37 that moves the nozzle 31. When a plurality of nozzles 31 are provided, the nozzle movement driving unit 37 may move the plurality of nozzles 31 integrally. For example, a plurality of nozzles 31 may be connected adjacent to each other to form a nozzle head, and the nozzle movement driving unit 37 may move the nozzle head. The nozzle movement driving unit 37 moves the nozzle 31 between a nozzle processing position and a nozzle standby position described below. The nozzle processing position is a position where the nozzle 31 discharges the processing liquid toward the main surface of the substrate W held by the substrate holding unit 2, for example, a position facing the central portion of the substrate W in the vertical direction. In the example of FIG. 3, the nozzle 31 located at the nozzle processing position is shown. The nozzle standby position is a position where the nozzle 31 does not discharge the processing liquid toward the main surface of the substrate W, for example, a position radially outside the substrate W.

[0058] In the example of FIG. 3, the nozzle movement driving unit 37 includes an arm 371, a support column 372, and a drive source 373. The support column 372 is provided radially outside the guard 7 described later and extends along the vertical direction. The arm 371 extends along the horizontal direction, the tip thereof is connected to the nozzle 31 (or the nozzle head), and the base end thereof is connected to the support column 372. The drive source 373 is controlled by the control unit 90 to rotate the support column 372 in the forward and reverse directions within a predetermined angular range about its central axis Q2. The drive source 373 includes, for example, a motor. When the support column 372 rotates in the forward and reverse directions within a predetermined angular range about the central axis Q2, the nozzle 31 reciprocates along the circumferential direction about the central axis Q2. The support column 372 is installed such that the nozzle processing position and the nozzle standby position are located on the movement locus of the nozzle 31. Note that the nozzle movement driving unit 37 is not necessarily limited to the embodiment of FIG. 3 and may include a linear motion mechanism such as a linear motor. The nozzle movement driving unit 37 corresponds to an example of a driving unit for performing processing on the substrate W.

[0059] When the processing liquid is discharged toward the main surface of the rotating substrate W in a state where the nozzle 31 is located at the nozzle processing position, the processing liquid adheres to the main surface of the substrate W. The processing liquid receives the centrifugal force accompanying the rotation of the substrate W and flows radially outward, scattering outside the peripheral edge of the substrate W. Thereby, processing according to the type of the processing liquid is performed on the substrate W.

[0060] The guard 7 receives the processing liquid scattered from the peripheral edge of the substrate W. The guard 7 has a cylindrical shape surrounding the substrate W held by the substrate holding unit 2.

[0061] The guard lifting and lowering drive unit 8 is controlled by the control unit 90 to lift and lower the guard 7. The guard lifting and lowering drive unit 8 lifts and lowers the guard 7 between the guard processing position and the guard standby position described below. The guard processing position is a position where the upper end of the guard 7 is vertically above the upper surface of the substrate W. In a state where the guard 7 is located at the guard processing position, the processing liquid scattered from the periphery of the substrate W is received by the inner peripheral surface of the guard 7. The guard standby position is a position where the upper end of the guard 7 is vertically below the upper surface of the spin base 21. In a state where the guard 7 is located at the guard standby position, it is possible to avoid collisions between the second transfer unit 122 and the substrate W and the guard 7 when the substrate W is loaded and unloaded.

[0062] In the example of FIG. 3, the guard lifting and lowering drive unit 8 has a so-called rack and pinion mechanism. Specifically, the guard lifting and lowering drive unit 8 includes a support plate 81, a rack 82, a gear 83, a motor 84, a fixing member 85, and a bellows 86. The support plate 81 extends radially outward from, for example, the cylindrical portion 71 of the guard 7. The support plate 81 has a plate-like shape and is provided in a posture where its thickness direction is along the vertical direction. The rack 82 has a rod-like shape extending along the vertical direction, and a plurality of teeth are provided on its side surface. The gear 83 is an external gear and meshes with the rack 82. The motor 84 is connected to the gear 83. The fixing member 85 fixes the motor 84 to the chamber 10. The motor 84 is controlled by the control unit 90 to rotate the gear 83 in the forward and reverse directions. Due to the rotation of this gear 83, the rack 82, the support plate 81, and the guard 7 are integrally lifted and lowered. The bellows 86 connects the lower surface of the support plate 81 and the floor surface of the chamber 10 and houses the rack 82, the gear 83, the motor 84, and the fixing member 85. The bellows 86 is stretchable in the vertical direction. Note that the guard lifting and lowering drive unit 8 is not limited to the rack and pinion mechanism, and for example, a ball screw mechanism having a motor or a linear motion mechanism having a linear motor may also be used. The guard lifting and lowering drive unit 8 corresponds to an example of a drive unit for performing processing on the substrate W. Note that the processing unit 1 may be provided with a plurality of guards 7 corresponding to a plurality of types of processing liquids.

[0063] In the example of FIG. 3, a cup 75 corresponding to the guard 7 is provided. The cup 75 has an annular (e.g., circular ring-shaped) recess (groove) surrounding the rotation axis Q1. The cup 75 receives the processing liquid that has flowed down the inner peripheral surface of the corresponding guard 7. For example, at the bottom of the cup 75, the upstream end of the drain pipe 76 is connected. The processing liquid received by each cup 75 is discharged to the outside of the processing unit 1 through the drain pipe 76.

[0064] In the example of FIG. 3, the camera 5 is provided inside the chamber 10. The camera 5 is fixed to the chamber 10 by a fixing member (not shown), for example. The camera 5 includes a solid-state imaging device such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor), an optical system such as a lens, and a camera control unit 51. The camera control unit 51 receives a signal from the solid-state imaging device and generates image data. The camera 5 outputs the image data to the control unit 90. The image data may be a frame of moving image data. The camera control unit 51 also includes a function for measuring time. For example, the camera control unit 51 includes a clock generator (clock generation circuit, not shown), and measures time based on the camera clock output by the clock generator. The camera 5 can generate image data (each frame) for each imaging time. The hardware configuration of the camera control unit 51 may be the same as that of the control unit 90, for example.

[0065] The camera 5 is provided at a position where its imaging area includes the object to be monitored inside the chamber 10. In the example of FIG. 3, the camera 5 is provided at a position vertically above and radially outside the substrate W held by the substrate holding unit 2. As shown in FIG. 3, the camera 5 may be provided radially outside the guard 7. In the example of FIG. 3, the camera 5 images the imaging area from an obliquely upper direction. In other words, the camera 5 images the imaging area along an obliquely lower direction.

[0066] The camera 5 outputs image data to the control unit 90. The control unit 90 can also function as an image processing unit that processes the image data. As will be described later, the control unit 90 detects changes in events within the chamber 10 based on the image data.

[0067] <First Example of Substrate Processing (Processing Step)> Next, a first example of substrate processing by the processing unit 1 will be described. Here, it is assumed that the processing unit 1 forms a coating film on the main surface (specifically, the upper surface) of the substrate W. FIG. 4 is a flowchart showing a first example of the operation of the processing unit 1. Steps S1 to S6 show an example of substrate processing (corresponding to an example of a processing step) for the substrate W, and step S10 shows a monitoring process for monitoring the operations of various driving units of the processing unit 1. The monitoring process will be described later.

[0068] This substrate processing for the substrate W can be realized by the control unit 90 controlling the substrate processing apparatus 100 based on the recipe information D1. The recipe information D1 is information indicating the processing procedure of the substrate W and is stored, for example, in the storage unit 94. In this substrate processing, while measuring the time, the control unit 90 outputs a control signal to the driving unit of the processing unit 1 based on the recipe information D1 and the time, causing the processing unit 1 to perform processing on the substrate W carried into the chamber 10.

[0069] In the example of FIG. 4, first, the substrate W is transported from the second transport unit 122 to the processing unit 1, and the substrate holding unit 2 holds the substrate W (step S1). For example, after the second transport unit 122 delivers the substrate W to the substrate holding unit 2, the control unit 90 outputs a control signal for displacing the chuck pin 22 to the holding position to the substrate holding unit 2 (specifically, the pin driving unit). In response to the control signal, the substrate holding unit 2 displaces the chuck pin 22 from the release position to the holding position. Thereby, the substrate holding unit 2 holds the substrate W.

[0070] Next, the processing unit 1 performs pre-processing on the substrate W (step S2). For the pre-processing, for example, a process of cleaning the substrate W can be applied. Note that step S2 does not necessarily have to be performed.

[0071] Here, in the pre-processing, the processing unit 1 supplies various processing liquids to the main surface of the substrate W while rotating the substrate W. For example, the processing unit 1 supplies pure water to the main surface of the substrate W. More specifically, first, the control unit 90 outputs a rising command as a control signal to the guard lifting drive unit 8. In response to the rising command, the guard lifting drive unit 8 raises the guard 7 to the guard processing position. Also, the control unit 90 outputs a rotation command as a control signal to the substrate holding unit 2 (specifically, the rotation drive unit 23). In response to the rotation command, the substrate holding unit 2 starts rotating the substrate W.

[0072] Also, the control unit 90 outputs a movement command as a control signal to the nozzle movement drive unit 37. The movement command in the pre-processing is a control signal for moving the nozzle 31B to the nozzle processing position. In response to the movement command, the nozzle movement drive unit 37 moves the nozzle 31B to the nozzle processing position. As a specific example, the nozzle movement drive unit 37 moves the nozzle 31B to a position where the nozzle 31B faces the center of the substrate W in the vertical direction.

[0073] Next, the control unit 90 outputs an open command as a control signal to the supply valve 33B. In response to the open command, the supply valve 33B opens the supply pipe 32B. Thereby, pure water is discharged from the discharge port of the nozzle 31B toward the main surface of the substrate W. The pure water that has landed on the central portion of the substrate W receives the centrifugal force accompanying the rotation of the substrate W and flows radially outward, scattering from the periphery of the substrate W. Thereby, the main surface of the substrate W is cleaned. Then, when the predetermined time defined by the recipe information D1 has elapsed, the control unit 90 outputs a close command as a control signal to the supply valve 33B. In response to the close command, the supply valve 33B closes the supply pipe 32B. Thereby, the discharge of pure water from the nozzle 31B stops.

[0074] Next, the processing unit 1 performs a coating process on the substrate W (step S3). More specifically, the processing unit 1 rotates the substrate W and discharges the coating liquid from the nozzle 31A toward the main surface of the substrate W. Here, it is assumed that in the recipe information D1, the first to third steps shown in the following table are defined as the steps corresponding to the coating process.

[0075]

Table 1

[0076] FIG. 5 is a diagram schematically showing an example of the timing of the output of the control signal by the control unit 90 in the coating process and the timing of the event change in the chamber 10 caused by the operation of the drive unit according to the control signal.

[0077] The first step is a step of starting the discharge of the coating liquid while moving the nozzle 31A to the central position. The central position mentioned here is an example of the nozzle processing position, and for example, it is a position that faces the center of the substrate W in the vertical direction. In the first step, the control unit 90 outputs a movement command to the nozzle movement drive unit 37 and an open command to the supply valve 33A. The movement command in the first step is a control signal for moving the nozzle 31A to the central position. The nozzle movement drive unit 37 moves the nozzle 31A to the central position in response to the movement command. The supply valve 33A opens the supply pipe 32A in response to the open command. In the example of FIG. 5, the movement command and the open command are output almost simultaneously, the coating liquid starts to be discharged after the start of the movement of the nozzle 31A, and then the movement of the nozzle 31A ends. The first required time of the first step is set in advance to a time sufficient for, for example, the movement of the nozzle 31A to the central position and the opening operation of the supply valve 33A to be completed, and can be set to about 1 second as a specific example.

[0078] The control unit 90 executes the second process in response to the elapse of the first required time from the start of the first process. The second process is a process of changing the rotation speed of the substrate W while continuously discharging the coating liquid. Here, it is assumed that the supply valve 33A keeps the supply pipe 32A open unless it receives a closing command. In the second process, the control unit 90 outputs a speed change command as a control signal to the substrate holding unit 2 (specifically, the rotation drive unit 23). The speed change command in the second process is a control signal for changing the rotation speed of the substrate W from the first speed value to the second speed value. The substrate holding unit 2 changes the rotation speed of the substrate W from the first speed value to the second speed value in response to the speed change command. In the example of FIG. 5, the rotation speed of the substrate W starts to change after the output of the speed change command, and then the change in the rotation speed of the substrate W substantially ends. The second required time of the second process is set in advance to a time sufficient for the change in the rotation speed of the substrate W to be completed, for example, and can be set to about 1.8 seconds as a specific example. When the rotation speed of the substrate W reaches the second speed value during the second process, the rotation speed of the substrate W ideally becomes constant at the second speed value.

[0079] The control unit 90 executes the third step in response to the elapse of the second required time since the start of the second step. The third step is a step of stopping the discharge of the coating liquid while changing the rotation speed of the substrate W. The control unit 90 outputs a speed change command to the substrate holding unit 2 and outputs a closing command to the supply valve 33A. The speed change command in the third step is a control signal for changing the rotation speed from the second speed value to the third speed value. The substrate holding unit 2 changes the rotation speed of the substrate W from the second speed value to the third speed value in response to the speed change command. The third speed value can be set higher than the second speed value, for example. Also, the supply valve 33A closes the supply pipe 32A in response to the closing command. Thereby, the discharge of the coating liquid from the discharge port of the nozzle 31A stops. In the example of FIG. 5, the speed change command and the closing command are output almost simultaneously, the discharge of the coating liquid stops after the rotation speed of the substrate W starts to change, and then the change in the rotation speed of the substrate W substantially ends. That is, the discharge of the coating liquid stops during the change in the rotation speed of the substrate W. The third required time of the third step is set in advance to a time sufficient to complete the change in the rotation speed of the substrate W and the stop of the discharge of the coating liquid, and can be set to about 4 seconds as a specific example.

[0080] By the coating process as described above, a liquid film of the coating liquid is formed on the main surface of the substrate W. After the coating process is completed, the control unit 90 may output a control signal to the substrate holding unit 2 to stop the rotation of the substrate W, may output a lowering command to the guard lifting drive unit 8 to lower the guard 7 to the guard standby position, or may output a movement command to the nozzle movement drive unit 37 to move the nozzle 31 to the nozzle standby position.

[0081] Next, the processing unit 1 dries the liquid film of the coating liquid on the main surface of the substrate W to form a coating film on the main surface of the substrate W (step S4). For example, the processing unit 1 may include a heater (not shown). The heater is provided, for example, between the substrate W and the spin base 21 to heat the substrate W. The heater may be, for example, an electric resistance type heater or an optical type heater that emits heating light (e.g., infrared rays). By heating the substrate W with the heater, the liquid film of the coating liquid on the substrate W can be dried. When the processing unit 1 completes the drying of the substrate W, the operation of the heater is stopped.

[0082] Next, the substrate holding unit 2 releases the holding of the substrate W (step S5). For example, the control unit 90 outputs a release command as a control signal to the substrate holding unit 2. The substrate holding unit 2 moves the chuck pin 22 from the holding position to the release position in response to the release command. Next, the second transfer unit 122 carries out the processed substrate W from the processing unit 1 (step S6).

[0083] As described above, by appropriately operating the various drive units of the processing unit 1, appropriate processing can be performed on the main surface of the substrate W.

[0084] Incidentally, a time difference occurs from when the control unit 90 outputs a control signal to the various drive units of the processing unit 1 until the event in the chamber 10 changes due to the operation of the drive unit in response to the control signal. The time difference may also be referred to as a delay time. Table 2 is a table showing examples of the type of drive unit, the type of control signal, and the type of event change.

[0085]

Table 2

[0086] For example, a delay time occurs from when the control unit 90 outputs a control signal to the supply valve 33 until the discharge state of the nozzle 31 changes. More specifically, a delay time occurs from when the control unit 90 outputs an open command until the nozzle 31 starts discharging the processing liquid. Also, a delay time occurs from when the control unit 90 outputs a close command until the discharge of the processing liquid from the nozzle 31 stops. One reason for the occurrence of these delay times is that it may take time for the opening and closing operations of the supply valve 33 to complete. For this reason, these delay times are relatively long.

[0087] In addition, a delay time may also occur from when the control unit 90 outputs a movement command to the nozzle movement drive unit 37 until the position of the nozzle 31 changes. However, since the nozzle movement drive unit 37 has a motor as a drive source and the nozzle 31 moves with high responsiveness to the operation of the motor, the delay time from the output of the movement command until the start of movement of the nozzle 31 is short compared to the operation of the supply valve 33. Also, a delay time may occur from when the control unit 90 outputs a speed change command to the substrate holding unit 2 until the rotational speed of the substrate W changes. Similarly, the delay time from the output of the speed change command until the start of change in the rotational speed of the substrate W is short compared to the delay time for the change in the coating state of the processing liquid.

[0088] Such various delay times may vary for each processing unit 1 due to factors such as variations in the load of each driving unit, manufacturing variations of each driving unit, and deterioration over time. And if such various delay times are different from the assumed time (for example, the design value), there is a possibility that the degree of processing on the substrate W may not be as assumed. For example, there is a possibility that the film thickness of the liquid film of the coating liquid on the main surface of the substrate W may deviate from the assumed film thickness. As a specific example, in the third step of the coating process, the time difference between the discharge stop time of the coating liquid and the change time of the rotation speed of the substrate W affects the film thickness of the liquid film. FIG. 6 is a diagram showing an example of the time change of the rotation speed of the substrate W in the third step of the coating process. In the example of FIG. 6, the discharge of the coating liquid stops while the rotation speed of the substrate W is increasing. If this discharge stop time t2 deviates from the assumed time, or if the change start time t1 of the rotation speed deviates from the assumed time, the value of the rotation speed of the substrate W at the discharge stop time t2 changes. Therefore, the film thickness of the liquid film fluctuates according to the deviation.

[0089] Also, the time difference between the discharge start time of the coating liquid in the first step of the coating process and the change time of the rotation speed of the substrate W in the second step of the coating process can also affect the film thickness of the liquid film. Therefore, if the discharge start time in the first step deviates, or if the change time of the rotation speed in the second step deviates, the film thickness of the liquid film may also deviate from the assumed film thickness. Alternatively, the time difference between the movement time and the discharge start time of the nozzle 31A in the first step can also affect the process. Therefore, if the movement time in the first step deviates, or if the discharge start time deviates, an excess or deficiency may occur in the process.

[0090] Therefore, in the present embodiment, the control unit 90 calculates the time difference (delay time) between the output of the control signal to each drive unit of the processing unit 1 and the event change in the chamber 10 accompanying the operation of the drive unit. Since the control unit 90 outputs the control signal to each drive unit based on the required time of each process defined by the recipe information D1, it knows the output time of the control signal. This output time is measured based on the control clock of the control unit 90. On the other hand, as will be described in detail later, the event change in the chamber 10 can be detected based on the image data generated by the camera 5. Since the camera 5 knows the imaging time of the image data, the control unit 90 can know the occurrence time of the event change based on the imaging time of the image data. However, the imaging time is measured based on the camera clock of the camera 5. Thus, since the output time of the control signal and the imaging time of the image data are measured by different clocks, a shift on the time axis may occur. Therefore, the control unit 90 synchronizes the current time measured based on the control clock and the current time measured based on the camera clock.

[0091] FIG. 7 is a flowchart showing an example of the monitoring process. The flow of FIG. 7 corresponds to an example of step S10 in FIG. 4. In the example of FIG. 7, first, the control unit 90 performs a synchronization process to reduce the difference between the current time measured by the control unit 90 and the current time measured by the camera 5 (step S11: synchronization step). For example, the control unit 90 may output a reset signal to the camera 5. The reset signal is, for example, a signal for initializing the time and includes information on the current time measured by the control unit 90. The camera control unit 51 responds to the reset signal and sets the current time measured based on the camera clock to the current time measured by the control unit 90. Thereby, the difference between the current time measured by the control clock and the current time measured by the camera clock can be reduced and can be made substantially the same. After this synchronization process, the control unit 90 and the camera control unit 51 can measure time on substantially the same time axis. Note that step S11 may be executed before step S1.

[0092] Next, the processing unit 1 repeatedly executes a set of steps S12 to S15 described below, for example, until the substrate processing is completed. Therefore, a series of processes from step S12 to step S15 are repeatedly executed in parallel with the substrate processing (steps S1 to S6).

[0093] In step S12 (imaging process), the camera 5 images the imaging area to generate image data IM1. The image data IM1 includes frames of moving image data. Since step S12 is repeatedly performed in parallel with the substrate processing as described above, each image data IM1 includes the state inside the chamber 10 according to the progress of the substrate processing. FIGS. 8 to 10 are diagrams schematically showing an example of the image data IM1. The image data IM1 in FIGS. 8(a), 8(b), 9(a), 9(b), and 10 are image data captured at different timings.

[0094] In the examples of FIGS. 8 to 10, the image data IM1 includes the entire upper opening of the guard 7 located at the guard processing position. In other words, the camera 5 is provided at a position where the entire upper opening of the guard 7 is included in the imaging area. In the example of FIG. 3, since the camera 5 is provided radially outside and vertically above the guard 7, the imaging direction of the camera 5 is obliquely downward. Therefore, the upper opening of the guard 7 having a circular shape in plan view is shown in an elliptical shape in the image data IM1.

[0095] FIG. 8(a) shows the image data IM1 captured immediately before the coating process of step S3, FIGS. 8(b) and 9(a) show the image data IM1 captured in the first step of the coating process, FIG. 9(b) shows the image data IM1 captured in the second step of the coating process, and FIG. 10 shows the image data IM1 captured in the third step of the coating process.

[0096] Next, in step S13 (event change determination step), the control unit 90 determines whether an event change has occurred in the chamber 10 based on the image data IM1. Here, the event change to be determined varies depending on the progress of the substrate processing. Below, as an example, the coating process in step S3 will be described.

[0097] For example, in the first step of the coating process, while the control unit 90 outputs a movement command to the nozzle movement drive unit 37, it outputs an open command to the supply valve 33A. Therefore, in the first step, as the determination process for the event change, the control unit 90 determines based on the image data IM1 whether the nozzle 31A has moved and whether the nozzle 31A has started discharging the coating liquid (step S13). For example, in FIG. 8(b), although the nozzle 31A has not yet reached the central position, the coating liquid is being discharged from the discharge port of the nozzle 31A. Below, first, an example of the determination method for whether the nozzle 31A has moved will be described, and then an example of the determination method for whether the nozzle 31A has started discharging the coating liquid will be described.

[0098] First, the control unit 90 specifies the position of the nozzle 31A in the image data IM1. For example, the control unit 90 may specify the position of the nozzle 31A by template matching using the reference image data RM1 of the nozzle 31A set in advance. In FIG. 8(b), an example of the reference image data RM1 is schematically superimposed and displayed on the image data IM1. In the example of FIG. 8(b), the reference image data RM1 includes a part of the nozzle 31A including the tip of the nozzle 31A. The vertical and horizontal sizes of the reference image data RM1 are smaller than those of the image data IM1. The reference image data RM1 is stored in the storage unit 94, for example. The control unit 90 specifies, by template matching for example, the region in the image data IM1 that has the highest similarity to the reference image data RM1 as the position of the nozzle 31A.

[0099] Then, the control unit 90 determines whether the difference between the position of the nozzle 31A and the position of the nozzle 31A in the image data IM1 generated in the previous step S12 is equal to or greater than a predetermined difference threshold value. When the difference is equal to or greater than the difference threshold value, the control unit 90 determines that the nozzle 31A is moving. When the difference is less than the difference threshold value, the control unit 90 determines that the nozzle 31A is stationary. And when the nozzle 31A is in a moving state in the next image data IM1 of the image data IM1 in which the nozzle 31A is in a stationary state, the control unit 90 may determine that the nozzle 31A has started to move.

[0100] Next, an example of a method for determining the start of discharge of the coating liquid will be described. When the coating liquid is discharged from the nozzle 31A, the coating liquid from the nozzle 31A adheres to the main surface of the substrate W. Therefore, a fluctuation (i.e., ripple) occurs in the liquid film of the coating liquid on the main surface of the substrate W directly below the nozzle 31A (see FIG. 8(b)). Note that the fluctuation of this liquid film is the largest when the lower end of the liquid columnar coating liquid from the nozzle 31A collides with the liquid film of the substrate W. After that, in a state where the liquid columnar coating liquid from the nozzle 31A continues to adhere to the liquid film of the substrate W, the fluctuation is relatively small.

[0101] Therefore, the control unit 90 may detect a change in the fluctuation of the liquid film at the liquid adhesion position of the coating liquid as a change in the discharge state of the coating liquid (here, the start of discharge) based on the image data IM1. Specifically, the control unit 90 may determine the magnitude of the fluctuation of the liquid film based on the pixel values of the determination region R1 including the liquid adhesion position of the coating liquid. The position and size of the determination region R1 in the image data IM1 are set in advance, for example, and stored in the storage unit 94. When the fluctuation of the liquid film at the liquid adhesion position increases, the variance (for example, the standard deviation) of the pixel values of the determination region R1 increases. Therefore, the control unit 90 determines whether the variance (for example, the standard deviation) of the pixel values of the determination region R1 is equal to or greater than a predetermined first variance threshold value. When the variance is equal to or greater than the first variance threshold value, the control unit 90 may determine that the fluctuation of the liquid film is large. Conversely, when the variance is less than the first variance threshold value, the control unit 90 may determine that the fluctuation of the liquid film is small.

[0102] Then, for example, when the control unit 90 determines that the nozzle 31A has started discharging the coating liquid when the fluctuation of the liquid film in the determination region R1 of the next image data IM1 is large while the fluctuation of the liquid film in the determination region R1 of the image data IM1 with small fluctuation of the liquid film in the determination region R1. Note that the control unit 90 may determine the magnitude of the fluctuation of the liquid film at the liquid landing position based on the image data IM1 using a learned model that has been machine-learned. For example, deep learning can be applied to machine learning. This also applies to the fluctuation of the liquid film described later.

[0103] As described above, during the execution of the first step of the coating process, the control unit 90 performs the movement determination process and the coating liquid discharge start determination process based on the image data IM1. When the control unit 90 has not detected both movement and discharge start, it executes step S12 again. On the other hand, when the control unit 90 detects at least one of the movement of the nozzle 31 or the start of discharge, it executes the following step S14.

[0104] In step S14 (calculation step), the control unit 90 obtains the time difference between the output time of the control signal and the occurrence time of the event change based on the synchronized time. Here, since step S11 has already been executed, the times measured by the control unit 90 and the camera 5 are synchronized. And since the control unit 90 has a function of measuring time, it knows the output time when the control signal is output. Also, since the control unit 90 detects the event change based on the image data IM1 as described above, it calculates the occurrence time of the event change based on the imaging time of the image data IM1.

[0105] For example, when the control unit 90 detects the start of the movement of the nozzle 31A in step S13, it calculates the movement time based on the imaging time of the image data IM1 when the nozzle 31A transitions from the stationary state to the moving state. As a specific example, the control unit 90 may calculate the average time of the imaging times of two temporally consecutive image data IM1 when the nozzle 31A transitions from the stationary state to the moving state as the movement time. This point can also be applied to the calculation of the occurrence time of other event changes. Then, the control unit 90 calculates the delay time from the output time of the movement command to the movement time. The control unit 90 may store in the storage unit 94 the delay time data indicating the delay time of the nozzle movement drive unit 37.

[0106] In response to a user input to the user interface 95, the control unit 90 may cause the delay time to be displayed on the display of the user interface 95. Thereby, the user can recognize the delay time of the nozzle movement drive unit 37. This operation is the same for the delay times of other drive units.

[0107] Note that in the above example, although the control unit 90 detects the start of the movement of the nozzle 31A as an event change, it may also detect the arrival of the nozzle 31A at the central position (that is, the end of the movement). For example, the control unit 90 may determine that the nozzle 31A has finished moving when the nozzle 31A is in the stationary state in the next image data IM1 of the image data IM1 in which the nozzle 31A is in the moving state. Then, the control unit 90 calculates the movement end time of the nozzle 31A based on the imaging time of the image data IM1 when the nozzle 31A transitions from the moving state to the stationary state, and calculates the delay time from the output time of the movement command to the movement end time. Alternatively, the control unit 90 may calculate both the delay time from the output time of the movement command to the movement start time and the delay time from the output time of the movement command to the movement end time.

[0108] Also, when the control unit 90 detects the start of discharge of the coating liquid in step S13, it determines the discharge start time based on the imaging time of the image data IM1 when the nozzle 31A starts discharging the coating liquid. Then, the control unit 90 calculates the delay time from the output time of the opening command to the discharge start time.

[0109] Next, the control unit 90 determines whether the delay time obtained in step S14 is within a predetermined reference range (step S15: pass / fail determination step). The reference range is set in advance according to the type of delay time. Therefore, the reference range for each delay time may be different from the reference range for other delay times. The reference range indicates a normal range for the corresponding delay time.

[0110] When the delay time is within the reference range, the control unit 90 determines whether to end the monitoring process (step S16). For example, the control unit 90 may determine to end the monitoring process when the substrate processing is completed. When the monitoring process is not ended, the processing unit 1 executes step S12 again.

[0111] On the other hand, when the delay time is outside the reference range, the control unit 90 may perform error processing (step S17). For example, as error processing, the control unit 90 may cause an error to be notified to a user interface 95 (not shown). For example, when the user interface 95 includes a display, the control unit 90 may cause the error to be displayed on the display. Alternatively, when the user interface 95 has a sound output unit such as a speaker, the control unit 90 may cause the error to be notified to the sound output unit. The content of the error may include information indicating the type of the drive unit targeted by the error and the delay time. Further, the control unit 90 may interrupt the substrate processing as error processing.

[0112] Since the above steps S12 to S15 are repeatedly executed as the substrate processing progresses, in step S12, the change in the state inside the chamber 10 can be included in the image data IM1. For example, when the processing progresses from FIG. 8(b), as shown in FIG. 9(a), the camera 5 generates image data IM1 in which the nozzle 31A reaches the central position and the coating liquid is discharged from the nozzle 31A toward the central portion of the substrate W.

[0113] When the processing further progresses and the second step of the coating process is executed, in step S12, for example, the image data IM1 shown in FIG. 9(b) is generated. In this second step, as described above, the control unit 90 outputs a speed change command to the substrate holding unit 2. The substrate holding unit 2 changes the rotation speed of the substrate W from the first speed value to the second speed value in response to the speed change command. Therefore, during the execution of the second step, the control unit 90 determines whether or not the rotation speed of the substrate W has changed based on the image data IM1 as a determination process of event change (step S13).

[0114] FIG. 9(b) shows the image data IM1 while the rotation speed of the substrate W is changing. As shown in FIG. 9(b), when the rotation speed of the substrate W changes, a change occurs in the fluctuation of the liquid film of the coating liquid on the main surface of the substrate W. This fluctuation becomes larger on the radially outer side than the liquid landing position of the coating liquid. Therefore, the control unit 90 may determine the magnitude of the fluctuation of the liquid film of the substrate W at a position radially outside the liquid landing position based on the image data IM1. For example, the control unit 90 may determine the magnitude of the fluctuation of the liquid film based on the pixel values of the determination region R2 on the radially outer side from the liquid landing position of the coating liquid. The position and size of the determination region R2 in the image data IM1 are set in advance so as not to include the fluctuation of the liquid film at the liquid landing position, for example. The control unit 90 determines whether or not the variance of the pixel values of the determination region R2 is equal to or greater than a predetermined second variance threshold, and when the variance is equal to or greater than the second variance threshold, it may be determined that the fluctuation of the liquid film is large. Conversely, when the variance of the determination region R2 is less than the second variance threshold, the control unit 90 may determine that the fluctuation of the liquid film is small.

[0115] Then, for example, when the control unit 90 determines that the fluctuation of the liquid film is large in the determination region R2 of the next image data IM1 of the image data IM1 with small fluctuation of the liquid film in the determination region R2, it may determine that the rotation speed of the substrate W has started to change.

[0116] As described above, during the execution of the second step of the coating process, the control unit 90 performs the determination process of the rotation speed change based on the image data IM1. When the control unit 90 detects a change in the rotation speed of the substrate W, it executes step S14.

[0117] In step S14, the control unit 90 calculates the time from the output time of the speed change command to the first speed change time when the rotation speed of the substrate W has changed. For example, the control unit 90 calculates the first speed change time based on the imaging time of the image data IM1 when the rotation speed of the substrate W starts to change. The first speed change time in this case corresponds to the change start time when the rotation speed of the substrate W starts to change. Then, the control unit 90 calculates the delay time from the output time of the speed change command to the first speed change time.

[0118] Next, the control unit 90 determines whether the delay time of the rotation driving unit 23 is within the reference range of the rotation driving unit 23 (step S15). If the delay time is outside the reference range, error processing (step S16) is performed.

[0119] In the above example, the control unit 90 detects the start of a change in the rotation speed of the substrate W as an event change. However, the control unit 90 may detect the arrival of the rotation speed of the substrate W at the second speed value (that is, the end of the change in the rotation speed). For example, when the control unit 90 determines that the fluctuation of the liquid film in the determination region R2 of the next image data IM1 of the image data IM1 with a large fluctuation of the liquid film in the determination region R2 is small, it determines that the change in the rotation speed of the substrate W has ended, and may calculate the first speed change time based on the imaging times of these image data IM1. The first speed change time in this case corresponds to the change end time when the change in the rotation speed of the substrate W has ended. In this case, the control unit 90 calculates, as the delay time, the delay time from the output time of the speed change command to the change end time. Note that the control unit 90 may calculate both the delay time from the output time of the movement command to the change start time and the delay time from the output time of the movement command to the change end time. This also applies to the second speed change time described later.

[0120] When the process further proceeds, the third step of the coating process is executed. In this third step, as described above, the control unit 90 outputs a speed change command to the substrate holding unit 2 while outputting a closing command to the supply valve 33A. The substrate holding unit 2 changes the rotation speed of the substrate W from the second speed value to the third speed value in response to the speed change command, and the supply valve 33A closes the supply pipe 32A in response to the closing command.

[0121] Therefore, during the execution of the third step, the control unit 90 determines, as an event change determination process, whether or not the rotation speed of the substrate W has changed and whether or not the discharge of the coating liquid has stopped, based on the image data IM1 (step S13). FIG. 10 shows the image data IM1 captured when the discharge of the coating liquid stops while the rotation speed of the substrate W is changing. As shown in FIG. 10, when the rotation speed of the substrate W changes, the fluctuation of the liquid film of the coating liquid on the main surface of the substrate W becomes large. This fluctuation can occur on the outer side in the radial direction from the liquid landing position of the coating liquid. Further, when the discharge of the coating liquid stops, the coating liquid is divided midway between the nozzle 31A and the substrate W, and the lower coating liquid falls toward the substrate W due to gravity. As a result, a relatively large fluctuation occurs in the coating liquid on the main surface of the substrate W at the liquid landing position.

[0122] Therefore, the control unit 90 may determine the stop of the discharge of the coating liquid based on the fluctuation of the liquid film at the liquid landing position. Specifically, the control unit 90 may determine whether or not the variance of the determination region R11 is equal to or greater than a predetermined third variance threshold value. When the variance is equal to or greater than the third variance threshold value, the control unit 90 determines that the fluctuation of the liquid film is large, and when the variance is less than the third variance threshold value, the control unit 90 determines that the fluctuation of the liquid film is small. The determination region R11 includes the liquid landing position of the coating liquid from the nozzle 31A located at the central position and is a region separated from the determination region R2, and is set in advance, for example. The third variance threshold value may be the same as or different from the first variance threshold value. Then, when the fluctuation of the liquid film is large in the determination region R11 of the next image data IM1 of the image data IM1 in which the fluctuation of the liquid film in the determination region R11 is small, the control unit 90 may determine that the discharge of the coating liquid has stopped.

[0123] Further, the control unit 90 may determine whether there is a change in the rotation speed of the substrate W based on the fluctuation of the liquid film at a position radially outside the liquid landing position. Specifically, the control unit 90 may determine that the fluctuation of the liquid film is large when the variance of the determination region R2 is equal to or greater than a predetermined fourth variance threshold, and may determine that the fluctuation of the liquid film is small when the variance is less than the fourth variance threshold. The fourth variance threshold may be the same as or different from the second variance threshold. Then, the control unit 90 detects a change in the rotation speed of the substrate W in the same manner as the determination in the second step.

[0124] As described above, during the execution of the third step of the coating process, the control unit 90 performs the determination process of the rotation speed change and the determination process of the discharge stop of the coating liquid based on the image data IM1. When the control unit 90 detects at least one of the rotation speed change and the discharge stop, it executes step S14.

[0125] When detecting a change in the rotation speed of the substrate W, in step S14, first, the control unit 90 calculates a second speed change time based on the imaging time of the image data IM1 when the rotation speed of the substrate W changes. Then, the control unit 90 calculates the delay time from the output time of the speed change command to the second speed change time.

[0126] When detecting the discharge stop of the coating liquid, in step S14, first, the control unit 90 calculates the discharge stop time based on the imaging time of the image data IM1 when the discharge of the coating liquid stops. Then, the control unit 90 calculates the delay time from the output time of the close command to the discharge stop time.

[0127] Next, the control unit 90 determines whether the delay time calculated in step S14 is within the reference range (step S15). If the delay time is outside the reference range, error processing (step S17) is performed.

[0128] As described above, the control unit 90 obtains the output time of the control signal to the drive unit based on the control clock, and obtains the occurrence time of the event change in the chamber 10 based on the imaging time measured by the camera clock (from step S11 to step S14). In the present embodiment, the control unit 90 synchronizes the current time measured by the control clock with the current time measured by the camera clock in step S11 (synchronization step). Therefore, the control unit 90 can calculate the time difference (here, the delay time) from the output time of the control signal to the occurrence time of the event change on substantially the same time axis, and can calculate it with higher accuracy. For example, the delay time for the nozzle movement drive unit 37, the delay time for the rotation drive unit 23, and the delay time for the change in the discharge state can be obtained with high accuracy.

[0129] Also, in the above example, the control unit 90 stores the delay time data indicating each delay time in the storage unit 94. Then, the control unit 90 causes the display of the user interface 95 to display the delay time in response to, for example, a user input. Thereby, the user can recognize each delay time of the processing unit 1 and can estimate the deterioration etc. of each drive unit. Further, the user may update the required time for each process in the recipe information D1 based on the recognized delay time so that the occurrence time of the event change becomes a more desirable time. For example, when the delay time of the drive unit is longer than the upper limit of the reference range, the recipe information D1 may be updated so that the output time of the control signal to the drive unit is at an earlier timing. Such an update can be performed by a user input to the user interface 95.

[0130] Also, in the above example, the control unit 90 determines whether or not each delay time is within the reference range (step S15). Therefore, the processing unit 1 can automatically determine whether the delay time is appropriate. Further, when the delay time is outside the reference range, the control unit 90 may update the output time of the control signal (that is, the required time for the process) in the recipe information D1 based on the deviation amount from the reference range of the calculated delay time so that the occurrence time of the event change becomes a more desirable time.

[0131] Note that in the above example, although the monitoring process is performed throughout the period during which the substrate process is carried out, it may be performed during at least a part of the period. The at least a part of the period is a period including the occurrence time of the event change to be calculated. For example, when calculating the change time of the discharge state, the at least a part of the period is a period including the change time when the discharge state of the coating liquid changes.

[0132] Also, in the above example, the control unit 90 detects a change in the fluctuation of the liquid film at the landing position of the coating liquid as a change in the discharge state of the coating liquid (start or stop of discharge) based on the image data IM1. According to this, the control unit 90 can detect a change in the discharge state with high accuracy.

[0133] Also, in the above example, the control unit 90 detects a change in the fluctuation of the liquid film at a position radially outside the landing position of the coating liquid as a change in the rotation speed of the substrate W based on the image data IM1. According to this, the control unit 90 can detect a change in the rotation speed based on the image data IM1.

[0134] <Guard lifting and lowering drive unit> In the above example, the control unit 90 outputs a control signal to the guard lifting and lowering drive unit 8, and the guard lifting and lowering drive unit 8 raises and lowers the guard 7 in response to the control signal. Therefore, the control unit 90 may calculate the delay time from the output time of the control signal to the guard lifting and lowering drive unit 8 to the lifting and lowering time of the guard 7. For example, the control unit 90 detects a change in the position of the guard 7 based on the image data IM1 (step S13). As a specific example, the control unit 90 may detect a change in the position of the guard 7 based on the temporal change in the pixel values of the determination region R3 (see also FIG. 8(a)) of the image data IM1. The determination region R3 is a region including at least a part of the upper end peripheral edge of the guard 7 and can be set in advance.

[0135] For example, when the similarity between the determination regions R3 of two temporally consecutive image data IM1 is less than a predetermined similarity threshold, the control unit 90 may determine that the guard 7 is moving up and down, and when the similarity is greater than or equal to the similarity threshold, the control unit 90 may determine that the guard 7 is stationary. Although the similarity is not particularly limited, for example, it may be a known similarity such as the sum of squared differences of pixel values (Sum of Squared Difference), the sum of absolute differences of pixel values (Sum of Absolute Difference), normalized cross-correlation, and zero-mean normalized cross-correlation.

[0136] Then, the control unit 90 calculates the lifting time of the guard 7 based on the imaging time of the image data IM1, and calculates the delay time from the output time of the control signal to the lifting time (step S14). Specifically, the control unit 90 may calculate the lifting start time based on the imaging time of the image data IM1 when the guard 7 transitions from the stationary state to the lifting state. In this case, the control unit 90 calculates the delay time from the output time of the control signal to the lifting start time. Alternatively, the control unit 90 may calculate the lifting end time based on the imaging time of the image data IM1 when the guard 7 transitions from the lifting state to the stationary state. In this case, the control unit 90 calculates the delay time from the output time of the control signal to the lifting end time. Note that the control unit 90 may calculate both the delay time from the output time to the lifting start time and the delay time from the output time to the lifting end time.

[0137] <Time difference between the occurrence times of different event changes> The control unit 90 may calculate the time difference between the occurrence times of different event changes obtained based on the image data IM1. FIG. 11 is a diagram for explaining the calculation of the time difference.

[0138] <Supply time of the processing liquid (= time difference between the discharge start time and the discharge stop time)> As shown in FIG. 11(a), the control unit 90 may calculate the supply time for supplying the coating liquid to the main surface of the substrate W based on the discharge start time and the discharge stop time t2 (see also FIG. 6) obtained based on the image data IM1. More specifically, the control unit 90 calculates the supply time by subtracting the discharge start time from the discharge stop time t2. The control unit 90 may store supply time data indicating the supply time in the storage unit 94. Further, the control unit 90 may cause the display of the user interface 95 to display the supply time in response to a user input to the user interface 95, for example. Thereby, the user can recognize the supply time. As a result, the user can recognize the occurrence of problems such as insufficient or excessive supply time. Moreover, as described above, since the user can also recognize the delay time for discharge start and the delay time for discharge stop, the user can also determine whether the cause of the supply time problem is due to discharge start or discharge stop.

[0139] Further, the control unit 90 may determine whether the supply time is within a predetermined supply reference range. When the supply time is within the supply reference range, since an appropriate coating process is being performed, the control unit 90 continues the process. On the other hand, when the supply time is outside the supply reference range, the control unit 90 may perform error processing, for example. Thereby, the user can recognize that an error has occurred in the supply time, and can quickly search for the cause of the supply time problem as described above.

[0140] <Time difference between discharge stop of coating liquid and rotation speed change in the third step> In the above example, in the third step of the coating process, the discharge of the coating liquid stops during the change in the rotation speed of the substrate W (see also FIGS. 5 and 6). For this reason, the time difference Δt between the second speed change time (for example, the change start time t1) and the discharge stop time t2 has a relatively large influence on the film thickness of the coating liquid. Therefore, as shown in FIG. 11(b), the control unit 90 may calculate the time difference Δt based on the change start time t1 and the discharge stop time t2 obtained based on the image data IM1. Specifically, the control unit 90 calculates the time difference Δt by subtracting the change start time t1 from the discharge stop time t2. The control unit 90 may store the time difference data indicating the time difference Δt in the storage unit 94. Further, the control unit 90 may cause the display of the user interface 95 to display the time difference Δt in response to a user input to the user interface 95, for example. Thereby, the user can recognize the occurrence of problems such as shortage or excess of the time difference Δt. Moreover, as described above, the user can also recognize the delay time regarding the change in the rotation speed and the delay time regarding the discharge stop. Therefore, the user can also determine whether the cause of the problem of the time difference Δt is due to the rotation drive unit 23 or due to the supply valve 33A.

[0141] Further, the control unit 90 may determine whether the time difference Δt is within a predetermined time difference reference range. When the time difference Δt is within the time difference reference range, since an appropriate coating process is being performed, the control unit 90 continues the process. On the other hand, when the time difference Δt is outside the time difference reference range, the control unit 90 may perform error processing, for example. Thereby, the user can recognize that a problem has occurred in the time difference Δt and can search for the cause of the problem of the time difference Δt as described above.

[0142] Incidentally, in the above example, the control unit 90 obtained the second speed change time (for example, the change start time t1) based on the fluctuation of the liquid film on the main surface of the substrate W in the image data IM1. However, the detection accuracy of the change in the rotation speed of the substrate W due to the fluctuation of the liquid film may not always be high. For example, the fluctuation of the liquid film at a position outside the liquid landing position can also change due to the change in the flow rate of the coating liquid. Therefore, when the change in the discharge state and the change in the rotation speed of the substrate W occur in parallel as in the third step of the coating process, the detection accuracy may decrease. Conversely, since the liquid landing position is close to the center of the substrate W, the fluctuation of the liquid film at the liquid landing position does not depend much on the change in the rotation speed of the substrate W.

[0143] Therefore, the control unit 90 may determine the second speed change time (for example, the change start time t1) based on the output time of the speed change command to the substrate holding unit 2. Specifically, as shown in FIG. 11(c), the control unit 90 sets the output time of the speed change command in the third step as the second speed change time. Then, the control unit 90 may subtract the output time of the speed change command from the discharge stop time t2 to calculate the time difference Δt. Thereby, the control unit 90 can calculate the time difference Δt with higher accuracy and simpler processing.

[0144] Here, for a more general explanation, a displacement driving unit is introduced. The displacement driving unit is, for example, the nozzle movement driving unit 37 or the rotation driving unit 23, and is a driving unit that displaces the displacement target (the nozzle 31 or the substrate W) in the chamber 10. Here, the control unit 90 calculates the time difference between the start time of the position change of the displacement target and the change time of the discharge state of the processing liquid. For example, the control unit 90 calculates the time difference between the movement start time of the nozzle 31 and the discharge start time of the processing liquid. In this case, the control unit 90 applies the output time of the control signal (for example, the movement command) to the displacement driving unit (for example, the nozzle movement driving unit 37) as the start time of the position change. That is, the control unit 90 calculates the time difference between the output time of the control signal to the displacement driving unit and the change time of the discharge state of the coating liquid calculated based on the image data IM1.

[0145] According to this, at the start time by the highly responsive displacement driving unit, since the output time of the control signal is applied, the control unit 90 can calculate the time difference more simply.

[0146] <Deterioration of the driving unit over time> The substrate W is sequentially carried into the processing unit 1. Since the control unit 90 calculates the above-described time difference (including the delay time) every time the substrate W is processed, time-dependent data D2 indicating the change over time of the time difference is generated. FIG. 12 is a diagram schematically showing an example of the time-dependent data D2. For example, when the control unit 90 calculates the delay time of each driving unit, the control unit 90 may add the delay time to the time-dependent data D2 corresponding to the driving unit to update the time-dependent data D2, and store the updated time-dependent data D2 in the storage unit 94.

[0147] The control unit 90 may display the time-dependent data D2 on the display of the user interface 95 in response to a user input to the user interface 95, for example. Thereby, the user can confirm the change over time of the time difference based on the time-dependent data.

[0148] <Variation between devices> In the above example, the substrate processing apparatus 100 includes a plurality of processing units 1. Each processing unit 1 calculates the above-described time difference (including the delay time) when processing the substrate W. Therefore, the control unit 90 generates inter-device data D3 indicating the variation between the plurality of processing units 1 for each time difference. FIG. 13 is a diagram schematically showing an example of the inter-device data D3. For example, when the control unit 90 calculates the delay time of each driving unit in each processing unit 1, the control unit 90 may add the delay time to the inter-device data D3 corresponding to the driving unit to update the inter-device data D3, and store the updated inter-device data D3 in the storage unit 94.

[0149] The control unit 90 may display the inter-device data D3 on the display of the user interface 95 in response to a user input to the user interface 95, for example. Thereby, the user can recognize the variation in the time difference between the plurality of processing units 1.

[0150] The control unit 90 may identify in advance, through experiments or the like, the processing unit 1 among the plurality of processing units 1 that is the most excellent in processing, and set each time difference of the processing unit 1 as a reference time. The reference time data indicating the reference time is stored in advance in the storage unit 94, for example. The control unit 90 may determine whether the difference between the time difference of each processing unit 1 calculated in step S14 and the reference time is equal to or greater than a predetermined threshold value. When the difference is equal to or greater than the threshold value, the control unit 90 may cause an error to be displayed on the display of the user interface 95. The error may include information indicating the processing unit 1 that is the target of the error and information indicating the type of the time difference.

[0151] <Synchronization processing> In the above example, the control unit 90 output a reset signal to the camera 5 to perform synchronization processing. However, it is not necessarily limited to this. For example, the displacement drive unit that controls the position of the displacement target in the chamber 10 has high responsiveness. The displacement drive unit includes, for example, the nozzle movement drive unit 37, the rotation drive unit 23, and the guard lifting drive unit 8. When the control unit 90 outputs a control signal to the displacement drive unit, the position of the displacement target starts to change at a time close to the output time of the control signal. If the responsiveness is high, the displacement start time at which the position of the displacement target starts to change can be regarded as almost coinciding with the output time. The displacement start time corresponds to the movement start time when the displacement target is the nozzle 31.

[0152] Therefore, the control unit 90 may perform synchronization processing as follows. First, the control unit 90 detects the start of the position change of the displacement target based on the image data IM1. This detection can be performed based on the temporal change of the pixel values of the image data IM1 as described above. Then, the control unit 90 obtains the displacement start time when the displacement target starts to change based on the imaging time of the image data IM1. Since this displacement start time is obtained based on the imaging time of the image data IM1, it is a time based on the camera clock. When the responsiveness is high, the deviation amount between the output time and the displacement start time mainly corresponds to the difference between the time axis of the control unit 90 and the time axis of the camera 5. Therefore, the control unit 90 performs synchronization processing based on the output time of the control signal and the displacement start time. Specifically, the control unit 90 corrects at least one of the measurement time by the control unit 90 and the measurement time by the camera 5 with the deviation amount, and reduces the difference between the current time measured by the control unit 90 and the current time measured by the camera 5.

[0153] According to this, the control unit 90 does not need to output a reset signal to the camera 5, and the camera control unit 51 does not need to perform a function corresponding to the reset signal. For this reason, the function of the camera control unit 51 can be simplified.

[0154] <Second Example of Substrate Processing> FIG. 14 is a flowchart showing a second example of the operation of the processing unit 1. In FIG. 14, the processing unit 1 executes steps S21 to S28 to perform substrate processing (corresponding to a processing step) on the substrate W. Here, the discharge unit 3 of the processing unit 1 includes three nozzles 31 (not shown). More specifically, the processing unit 1 includes a nozzle 31 for a chemical solution (for example, hydrofluoric acid), a nozzle 31 for a first rinse solution (for example, pure water), and a nozzle 31 for a second rinse solution (for example, isopropyl alcohol). Each nozzle 31 is connected to the downstream end of a corresponding supply pipe 32, and the upstream end of the supply pipe 32 is connected to a processing liquid supply source that supplies a corresponding processing liquid. The substrate processing in FIG. 14 is also realized by the control unit 90 controlling each component of the substrate processing apparatus 100 based on the recipe information D1.

[0155] First, the second transfer unit 122 transfers the substrate W to the processing unit 1, and the substrate holding unit 2 holds the substrate W (step S21). Next, the processing unit 1 performs chemical solution processing (step S22). Specifically, the substrate holding unit 2 starts rotating the substrate W, the guard lifting drive unit 8 raises the guard 7 to the guard processing position, and the nozzle movement drive unit 37 moves the nozzle 31 to the nozzle processing position. Next, the discharge unit 3 discharges the chemical solution from the nozzle 31 for the chemical solution toward the main surface of the substrate W. Then, in response to the elapse of a predetermined chemical solution time, the discharge unit 3 ends the discharge of the chemical solution.

[0156] Next, the processing unit 1 performs the first rinse process (step S23). Specifically, the discharge unit 3 discharges the first rinse solution from the nozzle 31 for the first rinse solution toward the main surface of the substrate W. Then, in response to the elapse of a predetermined first rinse time, the discharge unit 3 ends the discharge of the first rinse solution.

[0157] Next, the processing unit 1 performs an interruption process (step S24). Specifically, a close command is maintained for all the supply valves 33 for a predetermined interruption time (for example, 0.1 second). That is, the control unit 90 does not output an open command to the other supply valves 33 for the interruption time after outputting a close command to the supply valve 33 for the first rinse solution.

[0158] Next, the processing unit 1 performs the second rinse process (step S25). Specifically, the discharge unit 3 discharges the second rinse solution from the nozzle 31 for the second rinse solution toward the main surface of the substrate W. That is, the control unit 90 outputs an open command to the supply valve 33 for the second rinse solution in response to the elapse of the interruption time from the output time of the close command to the supply valve 33 for the first rinse solution. Then, in response to the elapse of the second rinse time from the output time of the open command, a close command is output to the supply valve 33 for the second rinse solution. Also, the nozzle movement drive unit 37 moves the nozzle 31 to the nozzle standby position.

[0159] Next, the processing unit 1 performs a drying process (step S26). Specifically, the substrate holding unit 2 increases the rotation speed of the substrate W (so-called spin drying). In response to the elapse of a predetermined drying time, the substrate holding unit 2 ends the rotation of the substrate W. Next, the substrate holding unit 2 releases the holding of the substrate W (step S27), and the second transfer unit 122 carries out the substrate W from the processing unit 1 (step S28).

[0160] As described above, the processing unit 1 can perform processing on the substrate W. Moreover, a short-time interruption process is performed between the first rinse process and the second rinse process. In this interruption process, although the discharge flow rate of the first rinse liquid decreases, the discharge flow rate does not become zero at the end of the interruption process. Therefore, until the discharge of the second rinse liquid is started, a liquid film can be maintained on the main surface of the substrate W. That is, the coverage of the substrate W can be ensured. Moreover, at the start of the discharge of the second rinse liquid, since the discharge flow rate of the first rinse liquid is small, the possibility of liquid splashing on the main surface of the substrate W can also be reduced.

[0161] However, in order to achieve both suppression of such liquid splashing and coverage, the discharge stop time of the first rinse liquid and the discharge start time of the second rinse liquid are important. Therefore, the control unit 90 may calculate these times. Specifically, first, the control unit 90 detects the discharge stop of the first rinse liquid based on the image data IM1, and calculates the delay time from the output time of the close command to the supply valve 33 for the first rinse liquid to the discharge stop time of the first rinse liquid based on the synchronized time. Further, the control unit 90 detects the start of the discharge of the second rinse liquid based on the image data IM1, and calculates the delay time from the output time of the open command to the supply valve 33 for the second rinse liquid to the discharge start time of the second rinse liquid based on the synchronized time. If the control unit 90 displays each delay time on the user interface 95, the user can confirm whether the discharge stop time of the first rinse liquid and the discharge start time of the second rinse liquid are appropriate. The control unit 90 may determine whether each delay time is within a reference range, calculate the time difference between the discharge stop time of the first rinse liquid and the discharge start time of the second rinse liquid, and determine whether the time difference is within a predetermined time difference reference range.

[0162] In addition, also in the second example of the substrate processing, the control unit 90 may calculate the time difference from the output time to the driving unit to the occurrence time of the event change.

[0163] As described above, the substrate processing apparatus 100 and the substrate processing method have been described in detail. However, the above description is illustrative in all aspects, and this disclosure is not limited thereto. In addition, the various modifications described above can be applied in combination as long as they do not contradict each other. And, a number of modifications not illustrated can be assumed without departing from the scope of this disclosure.

Description of Reference Numerals

[0164] 1 Processing unit 10 Chamber 2 Driving unit (substrate holding unit) 100 Substrate processing apparatus 23 Driving unit (rotation driving unit) 31, 31A, 31B Nozzle 32, 32A, 32B Supply pipe 33, 33A, 33B Supply valve 37 Driving unit (nozzle movement driving unit) 5 Camera 8 Driving unit (guard lifting and lowering driving unit) 90 Control unit IM1 Image data S11 Synchronization process (step) S12 Imaging process (step) S14 Calculation process (step) W Substrate

Claims

1. A processing step in which a control unit measures time while outputting a control signal to at least one driving unit of a processing unit to cause the processing unit to perform processing on a substrate carried into a chamber; An imaging step that is executed during at least a part of the processing step, in which a camera images the inside of the chamber to generate image data; A synchronization step of performing a synchronization process for reducing the difference between the current time measured by the control unit and the current time measured by the camera; A calculation step of detecting an event change in the chamber based on the image data, calculating the occurrence time of the event change based on the imaging time of the image data, and obtaining the time difference between the output time of the control signal and the occurrence time of the event change based on the synchronized time A substrate processing method comprising the above.

2. The substrate processing method according to Claim 1, In the processing step, the control unit outputs a movement command as the control signal to a nozzle movement driving unit to move a nozzle that discharges a processing liquid toward the main surface of the substrate by the nozzle movement driving unit, In the calculation step, the movement of the nozzle is detected based on the image data, and a delay time, which is the time difference from the output time of the movement command to the movement time of the nozzle, is obtained based on the synchronized time. A substrate processing method.

3. The substrate processing method according to Claim 1 or Claim 2, In the processing step, the control unit outputs an open command or a close command as the control signal to a supply valve provided in a supply pipe connected to a nozzle that discharges a processing liquid toward the main surface of the substrate, In the calculation step, a change in the discharge state of the processing liquid from the nozzle is detected based on the image data, and a delay time, which is the time difference from the output time of the control signal to the change time of the discharge state, is obtained based on the synchronized time. A substrate processing method.

4. The substrate processing method according to Claim 3, In the processing step, after the control unit outputs the open command to the supply valve to discharge the processing liquid from the nozzle, the control unit outputs the close command to the supply valve to stop the discharge of the processing liquid from the nozzle, In the calculation step, the start of discharge of the processing liquid from the nozzle in response to the opening command is detected based on the image data, the stop of discharge of the processing liquid from the nozzle in response to the closing command is detected based on the image data, and the supply time from the start time of discharge of the processing liquid to the stop time of discharge is obtained. A substrate processing method.

5. The substrate processing method according to claim 3, wherein In the calculation step, a change in the fluctuation of the processing liquid at the liquid landing position of the processing liquid on the main surface of the substrate is detected as a change in the discharge state of the processing liquid based on the image data. A substrate processing method.

6. The substrate processing method according to claim 1 or claim 2, wherein In the processing step, the control unit outputs a speed change command as the control signal to a rotation drive unit that rotates the substrate while discharging the processing liquid from the nozzle toward the main surface of the substrate. In the calculation step, a change in the fluctuation of the processing liquid on the main surface of the substrate at a position radially outside the liquid landing position of the processing liquid is detected as a change in the rotation speed of the substrate based on the image data. A substrate processing method.

7. The substrate processing method according to claim 1 or claim 2, wherein In the processing step, the control unit outputs the control signal to a displacement drive unit that displaces the position of the displacement target in the chamber, and outputs an opening command or a closing command as the control signal to a supply valve provided in a supply pipe connected to a nozzle that discharges the processing liquid onto the main surface of the substrate. In the calculation step, a change in the discharge state of the processing liquid from the nozzle is detected based on the image data, and the time difference between the output time of the control signal to the displacement drive unit and the change time of the discharge state of the processing liquid is obtained based on synchronized times. A substrate processing method.

8. The substrate processing method according to claim 7, wherein In the processing step, the control unit outputs the closing command to the supply valve and outputs a speed change command as the control signal to a rotation drive unit that is the displacement drive unit that rotates the substrate. In the calculation step, the stop of discharge of the processing liquid from the nozzle is detected based on the image data, and the time difference between the output time of the speed change command and the stop time of discharge of the processing liquid is obtained based on synchronized times. A substrate processing method.

9. The substrate processing method according to claim 1 or claim 2, wherein In the processing step, the control unit outputs the control signal to a displacement driving unit that displaces the position of the displacement target within the chamber. In the synchronization step, the start of the position change of the displacement target within the chamber is detected based on the image data, a displacement start time when the position of the displacement target starts to change is calculated based on the imaging time of the image data, and the synchronization process is performed based on the output time of the control signal and the displacement start time. A substrate processing method.

10. The substrate processing method according to claim 1 or claim 2, For each of the plurality of substrates, the processing step, the imaging step, the synchronization step, and the calculation step are performed. A substrate processing method for generating time-series data indicating the change over time of the time difference for the plurality of substrates.

11. The substrate processing method according to claim 1 or claim 2, For each of the plurality of processing units, the processing step, the imaging step, the synchronization step, and the calculation step are performed. A substrate processing method for generating inter-device data indicating the variation of the time difference between the plurality of processing units.

12. A chamber, A camera that images the inside of the chamber and generates image data, A driving unit for processing a substrate carried into the chamber, A control unit that outputs a control signal to the driving unit to cause the substrate carried into the chamber to be processed, Comprising: The control unit performs a synchronization process to reduce the difference between the current time measured by the control unit and the current time measured by the camera, detects an event change inside the chamber based on the image data, calculates the occurrence time of the event change based on the imaging time of the image data, and determines the time difference between the output time of the control signal and the occurrence time of the event change based on the synchronized time. A substrate processing apparatus.

Images