Substrate processing equipment

Abstract

To provide a wafer processing device capable of reducing running cost.SOLUTION: A wafer processing device comprises a wafer holding section 2, a chemical nozzle 31, a brush 4, a brush holding section 5, a brush movement driving section 410, a deposition detection section, a standby pod, a cleaning liquid supply section, and a control section 9. The chemical nozzle 31 discharges a chemical toward a principal surface of a wafer W which is held by the wafer holding section 2. The deposition detection section detects deposition of the chemical onto the brush holding section 5. The control section 9 determines that it is necessary to clean the brush holding section 5 when the deposition detection section detects the deposition of the chemical onto the brush holding section 5, and controls the cleaning liquid supply section to clean the brush holding section 5 with a cleaning liquid when the brush movement driving section 410 moves a pair of the brush holding section 5 and the brush 4 to the standby pod.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] Conventionally, a substrate processing apparatus that performs physical cleaning on a substrate has been disclosed (for example, Patent Document 1). In Patent Document 1, the substrate processing apparatus includes a spin chuck, a nozzle, a substrate processing brush, and a cleaning member cleaning device. The spin chuck rotates the substrate while holding the substrate in a horizontal posture. The nozzle supplies a cleaning liquid to the main surface of the substrate. The substrate processing brush is provided movably and moves relative to the main surface of the substrate while being in contact with the main surface of the substrate. Thereby, the substrate processing brush can rub and clean the main surface of the substrate.

[0003] The cleaning member cleaning device is a device that cleans the substrate processing brush. The cleaning member cleaning device includes a storage unit that stores a cleaning liquid. When the substrate processing brush moves inside the storage unit, the substrate processing brush is immersed in the cleaning liquid. Thereby, the substrate processing brush is cleaned. The substrate processing brush includes a sponge and a contact member holder that holds the sponge. In Patent Document 1, after immersing the sponge in the cleaning liquid, the contact member holder is immersed in the cleaning liquid.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the technique of Patent Document 1, even when there is a high probability that the cleaning of the contact member holder is unnecessary, the cleaning of the contact member holder can be performed. For this reason, there was a possibility that the running cost would increase.

[0006] Therefore, the purpose of this disclosure is to provide a substrate processing apparatus that can reduce running costs. [Means for solving the problem]

[0007] The first embodiment is a substrate processing apparatus comprising: a substrate holding unit that holds a substrate and rotates the substrate around a predetermined axis of rotation; a chemical nozzle that discharges a chemical solution toward the main surface of the substrate held by the substrate holding unit; a brush used for cleaning the main surface of the substrate held by the substrate holding unit; a brush holding unit provided above the brush and holding the brush; a standby pod; and a processing position in which the brush contacts the main surface of the substrate, and the standby pod. The system comprises a brush movement drive unit that moves the brush between the brush and the brush holder, an adhesion detection unit that detects the adhesion of the chemical solution to the brush holder, a cleaning liquid supply unit having a discharge port for supplying cleaning liquid to the standby pod, and a control unit. The control unit determines that cleaning of the brush holder is necessary when the adhesion detection unit detects the adhesion of the chemical solution to the brush holder, and controls the cleaning liquid supply unit to clean the brush holder with the cleaning liquid when the brush movement drive unit moves a set of the brush holder and the brush to the standby pod.

[0008] A second embodiment is a substrate processing apparatus according to the first embodiment, wherein the adhesion detection unit includes a flow meter for measuring the flow rate of the chemical solution discharged from the chemical solution nozzle, and detects the adhesion of the chemical solution to the brush holding unit based on the flow rate of the chemical solution measured by the flow meter.

[0009] A third embodiment is a substrate processing apparatus according to the second embodiment, wherein the adhesion detection unit further includes a brush position acquisition unit that acquires the brush position of the brush, and detects the adhesion of the chemical solution to the brush holding unit based on the flow rate of the chemical solution measured by the flow meter and the brush position of the brush acquired by the brush position acquisition unit.

[0010] A fourth embodiment is a substrate processing apparatus according to the third embodiment, further comprising a nozzle displacement drive unit that displaces the chemical solution nozzle to move the deposition position of the chemical solution on the main surface of the substrate, wherein the adhesion detection unit further includes a nozzle position acquisition unit that acquires the nozzle position of the chemical solution nozzle, and detects the adhesion of the chemical solution to the brush holding unit based on the flow rate of the chemical solution measured by the flow meter, the brush position of the brush acquired by the brush position acquisition unit, and the nozzle position of the chemical solution nozzle acquired by the nozzle position acquisition unit.

[0011] A fifth embodiment is a substrate processing apparatus according to any one of the first to fourth embodiments, wherein the adhesion detection unit includes a camera that images the brush holding unit and generates image data, and detects the adhesion of the chemical solution to the brush holding unit based on the image data.

[0012] A sixth embodiment is a substrate processing apparatus according to the fifth embodiment, comprising a storage unit for storing reference image data including the brush holding portion to which the chemical solution is not attached, and the adhesion detection unit detects the adhesion of the chemical solution to the brush holding portion based on a comparison of the image data and the reference image data.

[0013] A seventh embodiment is a substrate processing apparatus according to the fifth or sixth embodiment, wherein the camera is positioned to image the brush holding portion when the brush is in the processing position.

[0014] The eighth embodiment is a substrate processing apparatus according to any one of the fifth to seventh embodiments, wherein the camera is positioned to image the brush holding portion when the brush is located in the standby pod.

[0015] The ninth embodiment is a substrate processing apparatus according to any one of the fifth to eighth embodiments, wherein the camera is positioned to image the brush holding portion when the brush is located between the standby pod and the processing position.

[0016] The tenth embodiment is a substrate processing apparatus according to any one of the fifth to ninth embodiments, further comprising a brush drive unit that rotates the brush and the brush holder unit together, wherein the camera generates a plurality of image data by sequentially imaging the brush holder unit while the brush drive unit is rotating the brush and the brush holder unit.

[0017] The eleventh embodiment is a substrate processing apparatus according to any one of the first to tenth embodiments, wherein the control unit moves the brush and the brush holding unit together on the main surface of the substrate with the chemical solution discharged from the chemical solution nozzle, and performs scrubbing of the main surface of the substrate, wherein in a plan view, a virtual straight line along the trajectory of the chemical solution from the discharge port of the chemical solution nozzle to the main surface of the substrate intersects a virtual straight line along the trajectory of the movement of the brush in the scrubbing.

[0018] The twelfth embodiment is a substrate processing apparatus according to any one of the first to eleventh embodiments, wherein the cleaning liquid supply unit includes a first cleaning nozzle that discharges the cleaning liquid toward the brush holding unit and a second cleaning nozzle that discharges the cleaning liquid toward the brush.

[0019] The 13th embodiment is a substrate processing apparatus according to the 12th embodiment, wherein the cleaning liquid supply unit discharges the cleaning liquid from the first cleaning nozzle only for a portion of the brush cleaning time, a first hour, and discharges the cleaning liquid from the second cleaning nozzle for a second hour at least after the first hour.

[0020] The fourteenth embodiment is a substrate processing apparatus according to the thirteenth embodiment, wherein the cleaning liquid supply unit does not discharge the cleaning liquid from the second cleaning nozzle for at least a portion of the first time.

[0021] The 15th aspect is a substrate processing apparatus according to any one of the 1st to 14th aspects, wherein the control unit causes the brush moving drive unit to raise and lower the brush in the standby pod to bring the brush into contact with the cleaning liquid, and causes the brush holding unit to come into contact with the cleaning liquid.

Effect of the Invention

[0022] According to the 1st aspect, when the probability that the brush holding unit needs to be cleaned is high, the brush holding unit can be cleaned. Conversely, unnecessary cleaning of the brush holding unit can be suppressed. Therefore, the running cost of the substrate processing apparatus can be reduced.

[0023] According to the 2nd aspect, the adhesion of the chemical solution to the brush holding unit can be detected with a simple configuration.

[0024] According to the 3rd aspect, the adhesion of the chemical solution to the brush holding unit can be detected with higher accuracy.

[0025] According to the 4th aspect, the adhesion of the chemical solution to the brush holding unit can be detected with higher accuracy.

[0026] According to the 5th aspect, the adhesion of the chemical solution to the brush holding unit can be detected with higher accuracy.

[0027] [[ID=二十七]]According to the 6th aspect, the adhesion of the chemical solution to the brush holding unit can be detected by a simple process.

[0028] According to the 7th aspect, the adhesion detection unit can detect the adhesion of the chemical solution to the brush holding unit during scrubber cleaning.

[0029] According to the 8th aspect, the adhesion of the chemical solution to the brush holding unit can be detected in the standby pod. Since no chemical solution is supplied in the standby pod, the image data contains almost no flowing chemical solution. Therefore, the adhesion of the chemical solution can be detected with higher accuracy.

[0030] According to the ninth embodiment, the adhesion of the chemical solution to the brush holder can be detected while the brush is moving between the standby pod and the processing position. Since no chemical solution is supplied while the brush is moving, the image data contains almost no flowing chemical solution. Therefore, the adhesion of the chemical solution can be detected with higher accuracy.

[0031] According to the tenth embodiment, the adhesion detection unit can check the entire circumferential surface of the brush holding unit, so that the adhesion of the chemical solution can be detected with higher accuracy.

[0032] According to the eleventh embodiment, if the flow rate increases abnormally, the chemical solution discharged from the chemical solution nozzle may adhere to the moving brush holder. However, the adhesion detection unit detects the adhesion of the chemical solution to the brush holder, and cleaning of the brush holder is performed in the standby pod. This ensures that the brush holder is properly cleaned.

[0033] According to the twelfth embodiment, cleaning fluid can be reliably supplied to the brush holder and the brush.

[0034] According to the 13th embodiment, since the cleaning solution is discharged from the first cleaning nozzle only for the first hour, the amount of cleaning solution used can be reduced.

[0035] According to the 14th embodiment, the second cleaning nozzle does not discharge cleaning fluid for at least a portion of the first hour, so the amount of cleaning fluid used can be reduced.

[0036] According to the 15th embodiment, there is no need to provide multiple cleaning nozzles, and the configuration of the cleaning fluid supply unit can be simplified. [Brief explanation of the drawing]

[0037] [Figure 1] This is a schematic longitudinal cross-sectional view showing an example of the configuration of a processing unit belonging to a substrate processing apparatus according to the first embodiment. [Figure 2] This is a schematic plan view showing an example of the configuration of a processing unit according to the first embodiment. [Figure 3] This is a schematic block diagram showing an example of the electrical configuration of a processing unit according to the first embodiment. [Figure 4] This diagram schematically shows an example of the configuration of a standby pod, a part of the cleaning fluid supply unit, a brush, and a brush holder according to the first embodiment. [Figure 5] A flowchart illustrating an example of the operation of the processing unit. [Figure 6] This diagram schematically shows the time-dependent changes in the state of the processing unit during scrubber cleaning. [Figure 7] This diagram illustrates the positional relationship between the chemical nozzle and the brush holder. [Figure 8] This flowchart shows an example of the operation related to brush cleaning by the processing unit. [Figure 9] This is a timing chart showing an example of the operation of the processing unit during the first brush cleaning. [Figure 10] This is a plan view showing an example of the configuration of a processing unit according to the second embodiment. [Figure 11] This diagram schematically shows an example of the configuration of a standby pod, a part of the cleaning fluid supply unit, a brush, and a brush holder according to the second embodiment. [Figure 12] This is a schematic plan view showing an example of the configuration of a processing unit according to the third embodiment. [Figure 13] This is a schematic block diagram showing an example of the electrical configuration of a processing unit according to the third embodiment. [Figure 14] This flowchart shows an example of the operation related to brush cleaning by the processing unit according to the third embodiment. [Figure 15] This is a longitudinal cross-sectional view schematically showing an example of the configuration of a processing unit according to the fourth embodiment. [Figure 16] This diagram schematically shows an example of image data generated by a camera. [Figure 17] This is a schematic block diagram showing an example of the electrical configuration of a processing unit according to the fourth embodiment. [Figure 18]This flowchart shows an example of the operation related to brush cleaning of the processing unit. [Figure 19] This is a diagram illustrating another first example of camera positioning. [Figure 20] This is a diagram illustrating another example of camera positioning. [Figure 21] This figure schematically shows an example of the configuration of a processing unit according to the fifth embodiment. [Modes for carrying out the invention]

[0038] The embodiments will be described in detail below with reference to the drawings. Note that, for the purpose of ease of understanding, the dimensions and number of parts in the drawings are exaggerated or simplified as needed. Also, parts with similar configurations and functions are denoted by the same reference numerals, and redundant explanations are omitted in the following description.

[0039] Furthermore, in the following explanations, similar components will be denoted by the same symbols, and their names and functions will also be the same. Therefore, detailed explanations of them may be omitted to avoid redundancy.

[0040] Furthermore, even if ordinal numbers such as "first" or "second" are used in the following descriptions, these terms are used for convenience to facilitate understanding of the embodiments and are not limited to the order that may result from these ordinal numbers.

[0041] When expressions indicating relative or absolute positional relationships are used (e.g., "in one direction," "along one direction," "parallel," "orthogonal," "center," "concentric," "coaxial," etc.), unless otherwise specified, such expressions shall not only strictly represent the positional relationship but also represent a state in which there is a relative displacement in terms of angle or distance within a tolerance or a range in which equivalent functionality is obtained. When expressions indicating equality are used (e.g., "identical," "equal," "homogeneous," etc.), unless otherwise specified, such expressions shall not only strictly represent a state in which there is a quantitatively exact equality but also represent a state in which there is a difference within a tolerance or a range in which equivalent functionality is obtained. When expressions indicating shape are used (e.g., "quadrilateral" or "cylindrical"), unless otherwise specified, such expressions shall not only strictly represent the geometrically exact shape but also represent a shape with features such as concavities or chamfers within a range in which equivalent effects are obtained. When expressions such as "possess," "equip," "include," or "have" a single component are used, such expressions are not exclusive expressions that exclude the existence of other components. When the expression "at least one of A, B, and C" is used, it includes A only, B only, C only, any two of A, B, and C, and all of A, B, and C.

[0042] <First Embodiment> Figure 1 is a schematic longitudinal cross-sectional view showing an example of the configuration of a processing unit 1 belonging to the substrate processing apparatus according to the first embodiment. Figure 2 is a schematic plan view showing an example of the configuration of a processing unit 1 according to the first embodiment. Figure 3 is a schematic block diagram showing an example of the electrical configuration of a processing unit 1 according to the first embodiment. The substrate processing apparatus may include a plurality of processing units 1 and a transport robot that loads and unloads substrates W to each of the plurality of processing units 1.

[0043] Processing unit 1 can perform scrubber cleaning on the main surface of the substrate W. Scrubber cleaning will be described in detail later. The substrate W is, for example, a semiconductor wafer, a substrate for liquid crystal displays, an organic EL (Electroluminescence) substrate, an FPD (Flat Panel Display) substrate, an optical display substrate, a magnetic disk substrate, an optical disk substrate, a magneto-optical disk substrate, a photomask substrate, or a solar cell substrate. The substrate W has a thin, flat shape. In the following, 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 thickness of the substrate W is, for example, about 0.5 mm or more and about 3 mm or less.

[0044] As shown in Figures 1 to 3, the processing unit 1 includes a substrate holding unit 2, a chemical nozzle 31, a brush 4, a brush holding unit 5, a brush movement drive unit 410, an adhesion detection unit 6, a standby pod 7, a cleaning liquid supply unit 8, and a control unit 9.

[0045] The substrate holder 2 holds the substrate W in a horizontal position and rotates the substrate W around the rotation axis Q1. Here, "horizontal position" refers to a position where the thickness direction of the substrate W is aligned with the vertical direction. The rotation axis Q1 is an axis that passes through the center of the substrate W and is aligned with the vertical direction. The substrate holder 2 may also be called a spin chuck.

[0046] In the example shown in Figure 1, the substrate holder 2 includes a spin base 21, chuck pins 22, and a rotation drive unit 23. The spin base 21 has a plate-like shape (e.g., a disc shape) and is positioned so that its thickness direction is aligned with the vertical direction. Multiple chuck pins 22 are provided on the upper surface of the spin base 21. The multiple chuck pins 22 are provided at equal intervals along the circumferential direction with respect to the rotation axis Q1. The multiple chuck pins 22 are provided so as to be displaceable between the holding position and the release position, which will be described below. The holding position is the position in which the chuck pins 22 contact the periphery of the substrate W. The multiple chuck pins 22 hold the substrate W by stopping at their respective holding positions. Figures 1 and 2 show the chuck pins 22 stopped at the holding positions. The release position is the position in which each chuck pin 22 is separated from the substrate W. The multiple chuck pins 22 release the substrate W by stopping at their respective release positions. The substrate holding section 2 also includes a pin drive section (not shown) that displaces the chuck pin 22. The pin drive section includes a drive source such as a motor and an air cylinder, and is controlled by the control section 9.

[0047] The rotary drive 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 from the lower surface of the spin base 21 along the rotation axis Q1. The motor 232 is controlled by the control unit 9 and rotates the shaft 231 around the rotation axis Q1. As a result, the spin base 21, chuck pin 22, and substrate W rotate together around the rotation axis Q1.

[0048] Note that the substrate holding part 2 does not necessarily need to have chuck pins 22. For example, the substrate holding part 2 may hold the substrate W using a chuck method such as a vacuum chuck, an electrostatic chuck, or a Bernoulli chuck.

[0049] The chemical nozzle 31 discharges the chemical solution toward the main surface (specifically, the top surface) of the substrate W held by the substrate holding part 2. The chemical solution is a liquid used for scrubbing the substrate W, and a specific example will be described later. The chemical nozzle 31 is positioned vertically above the substrate W held by the substrate holding part 2. In the examples of Figures 1 and 2, the chemical nozzle 31 is positioned radially outward from the substrate W held by the substrate holding part 2. The chemical nozzle 31 has a discharge port 3a at its tip, and discharges the chemical solution from the discharge port 3a. As shown in Figure 1, the chemical nozzle 31 may discharge the chemical solution diagonally toward the rotation axis Q1 and vertically downward. The chemical solution discharged from the chemical nozzle 31 may land on the main surface of the substrate W. The chemical solution that lands on the main surface of the substrate W is affected by the centrifugal force accompanying the rotation of the substrate W and flows radially outward, scattering outward from the periphery of the substrate W.

[0050] In the examples shown in Figures 1 and 2, the chemical nozzle 31 is used for both the chemical solution and the rinsing solution. The rinsing solution is a liquid used to push the chemical solution over the main surface of the substrate W, and a specific example will be described later. In the examples shown in Figures 1 and 2, the chemical nozzle 31 is connected to the downstream end of the supply pipe 32, and the upstream end of the supply pipe 32 is connected to the downstream ends of supply pipes 32a and 32b. The upstream end of supply pipe 32a is connected to a chemical supply source. The chemical supply source has a tank (not shown) for storing the chemical solution and supplies the chemical solution to the upstream end of supply pipe 32a. As the chemical solution, for example, a solution containing at least one of sulfuric acid, acetic acid, nitric acid, hydrochloric acid, hydrofluoric acid, ammonia water, and hydrogen peroxide can be used. Specifically, a mixture of ammonia and hydrogen peroxide (SC1) and TMAH (tetramethylammonium hydroxide) can be used as the chemical solution.

[0051] The supply pipe 32a is equipped with a supply valve 33a, a flow control valve 34a, and a flow meter 35a. The supply valve 33a switches the supply pipe 32a open and closed. The flow control valve 34a adjusts the flow rate of the chemical solution flowing through the supply pipe 32a. The supply valve 33a and the flow control valve 34a are controlled by the control unit 9. The flow meter 35a measures the flow rate of the chemical solution flowing through the supply pipe 32a and outputs an electrical signal indicating the measurement result to the control unit 9. The flow meter 35a is, for example, an ultrasonic flow meter. The control unit 9 may control the flow control valve 34a based on the flow rate measured by the flow meter 35a.

[0052] The upstream end of the supply pipe 32b is connected to a rinse liquid supply source. The rinse liquid supply source has a tank (not shown) for storing the rinse liquid and supplies the rinse liquid to the upstream end of the supply pipe 32b. As the rinse liquid, pure water, carbonated water, electrolyzed ionized water, hydrogen water, magnetic water, or ammonia water at a diluted concentration (e.g., about 1 ppm) can be used.

[0053] The supply pipe 32b is equipped with a supply valve 33b, a flow control valve 34b, and a flow meter 35b. The supply valve 33b switches the supply pipe 32b open and closed. The flow control valve 34b adjusts the flow rate of the rinse liquid flowing through the supply pipe 32b. The supply valve 33b and the flow control valve 34b are controlled by the control unit 9. The flow meter 35b measures the flow rate of the rinse liquid flowing through the supply pipe 32b and outputs an electrical signal indicating the measurement result to the control unit 9. The flow meter 35b is, for example, an ultrasonic flow meter. The control unit 9 may control the flow control valve 34b based on the flow rate measured by the flow meter 35b.

[0054] Brush 4 is used for scrubbing. Specifically, a cleaning solution is supplied to the main surface of the substrate W, and while the brush 4 is in contact with the main surface of the substrate W, it moves relative to the main surface of the substrate W. This allows the brush 4 to scrub and clean the main surface of the substrate W (scrubbing). Brush 4 is, for example, a sponge material made of resin such as polyvinyl alcohol. Brush 4 has, for example, a cylindrical shape with a central axis along the vertical direction. The lower surface 4a of brush 4 is in contact with the main surface of the substrate W. The lower surface 4a of brush 4 is, for example, a flat surface parallel to the main surface of the substrate W and has a circular shape in plan view. Plan view here means looking with the line of sight along the vertical direction.

[0055] The brush holder 5 holds the brush 4. The brush holder 5 is positioned vertically above the lower surface 4a of the brush 4 and can hold the upper end portion of the brush 4. Figure 4 is a schematic diagram showing an example of the configuration of a standby pod 7, a part of the cleaning fluid supply unit 8, the brush 4, and the brush holder 5 according to the first embodiment. In the example of Figure 4, the brush holder 5 includes a first member 51 and a second member 52. The brush 4 can be fixed to the first member 51. The brush 4 protrudes vertically downward from the lower end of the first member 51. That is, the lower surface 4a of the brush 4 is located vertically below the lower end of the first member 51. The first member 51 has, for example, a cylindrical side surface having a larger diameter than the brush 4. The second member 52 is positioned vertically above the first member 51 and is detachably attached to the first member 51. The second member 52 has, for example, a cylindrical side surface having approximately the same diameter as the first member 51. The brush 4, the first member 51, and the second member 52 may be arranged coaxially.

[0056] For example, the second member 52 is fixed to the first member 51 by a screw structure. In the example shown in Figure 4, the upper part of the first member 51 is provided with a male screw portion 511 that protrudes vertically upward. The male screw portion 511 has a cylindrical shape with a central axis along the vertical direction, and screw threads are formed on the side surface of this cylindrical shape. The lower part of the second member 52 is provided with a female screw portion 521 that is recessed vertically upward and has female threads formed thereon. Screw threads are also formed on the inner circumferential surface of the female screw portion 521. The male screw portion 511 of the first member 51 is connected to the female screw portion 521 of the second member 52 by a screw structure, thereby allowing the first member 51 to be detachably attached to the second member 52.

[0057] When the brush 4 becomes worn, a worker can replace it. Specifically, the worker removes the first component 51 from the second component 52 and attaches the first component 51, to which the new brush 4 is attached, to the second component 52. This allows the worker to replace the worn brush 4 with a new brush 4.

[0058] In the examples shown in Figures 1 and 2, the processing unit 1 is provided with an arm 400. The arm 400 extends horizontally. Inside the arm 400 is a brush drive unit 401. The brush drive unit 401 is controlled by a control unit 9. The brush drive unit 401 may include a rotation drive unit that rotates the brush 4 around a rotation axis Q2. The rotation axis Q2 is, for example, an axis that passes through the center of the brush 4 and is aligned vertically. The brush drive unit 401 includes a shaft 4011 and a motor (not shown). The shaft 4011 extends along the rotation axis Q2 and protrudes vertically downward from the lower surface of the arm 400. The lower end of the shaft 4011 is connected to the upper surface of the brush holder 5 (i.e., the upper surface of the second member 52). The motor rotates the shaft 4011 around the rotation axis Q2. As a result, the brush holder 5 connected to the shaft 4011 and the brush 4 held by the brush holder 5 rotate together around the rotation axis Q2.

[0059] The brush drive unit 401 may also be provided with a braking drive unit (not shown) to stop the rotation of the shaft 4011, or with a pressing drive unit (not shown) that presses the brush 4 against the main surface of the substrate W with a controllable pressing force.

[0060] The brush movement drive unit 410 moves the brush 4 and the brush holder 5 together. In the examples in Figures 1 and 2, the brush movement drive unit 410 moves the arm 400, the brush holder 5, and the brush 4 together. In the following, the brush movement drive unit 410 may be described using the brush 4 or the brush holder 5 as representative objects of movement.

[0061] The brush movement drive unit 410 moves the brush 4 along, for example, the vertical and horizontal directions. In the example in Figure 1, the brush movement drive unit 410 includes a vertical drive unit 411 and a horizontal drive unit 412. The vertical drive unit 411 moves the brush 4 along the vertical direction. The vertical drive unit 411 can also be said to be a lifting drive unit. The vertical drive unit 411 includes, for example, a drive source (not shown), such as a motor, and a power transmission unit (not shown) that converts the rotational force from the drive source into a vertical force. The horizontal drive unit 412 moves the brush 4 along the horizontal direction. The horizontal drive unit 412 includes, for example, a drive source (not shown), such as a motor, and a power transmission unit (not shown) that converts the rotational force from the drive source into a horizontal force. These power transmission units include, for example, a ball screw mechanism or a cam mechanism.

[0062] The brush movement drive unit 410 moves the brush 4 between a processing position where the brush 4 contacts the main surface of the substrate W and a standby pod 7, which will be described in detail later. The brush movement drive unit 410 can also move the brush 4 along the main surface of the substrate W while the brush 4 is in contact with the main surface of the substrate W.

[0063] The standby pod 7 is positioned in a standby location for the brush 4. In the example shown in Figure 2, the standby pod 7 is located radially outward from the substrate holder 2. The standby pod 7 has, for example, a cylindrical side wall that surrounds the brush 4 and the brush holder 5. The standby pod 7 opens at least vertically upward (see also Figure 4). After the brush movement drive unit 410 moves the brush 4 to a position directly above the standby pod 7, the brush 4 can be lowered to house it inside the standby pod 7.

[0064] The cleaning fluid supply unit 8 has discharge ports 8a and 8b for supplying cleaning fluid to the standby pod 7. In the example shown in Figure 4, the cleaning fluid supply unit 8 includes a first cleaning nozzle 81a and a second cleaning nozzle 81b. The first cleaning nozzle 81a is attached to the side wall of the standby pod 7. The first cleaning nozzle 81a has a discharge port 8a that opens toward the interior of the standby pod 7 and discharges cleaning fluid from the discharge port 8a toward the brush holding unit 5. The second cleaning nozzle 81b is also attached to the side wall of the standby pod 7. The second cleaning nozzle 81b has a discharge port 8b that opens toward the interior of the standby pod 7 and discharges cleaning fluid from the discharge port 8b toward the brush 4. In the example shown in Figure 4, the first cleaning nozzle 81a is positioned at a height corresponding to the brush holding unit 5, and the second cleaning nozzle 81b is positioned at a height corresponding to the brush 4. Here, since the brush holder 5 is positioned higher than the lower surface 4a of the brush 4, the first cleaning nozzle 81a is positioned higher than the second cleaning nozzle 81b. In a plan view, the positions of the first cleaning nozzle 81a and the second cleaning nozzle 81b may be the same, as shown in Figure 4, or they may be different, as shown in Figure 2.

[0065] The first cleaning nozzle 81a is connected to the downstream end of the supply pipe 82a, and the upstream end of the supply pipe 82a is connected to a cleaning liquid supply source. The second cleaning nozzle 81b is connected to the downstream end of the supply pipe 82b, and the upstream end of the supply pipe 82b is connected to a cleaning liquid supply source. The cleaning supply source has a tank (not shown) for storing cleaning liquid and supplies cleaning liquid to the upstream ends of the supply pipes 82a and 82b. As the cleaning liquid, for example, pure water can be used. Alternatively, any of the liquids exemplified as rinsing liquids above may be used as the cleaning liquid.

[0066] A supply valve 83a is provided in supply pipe 82a, and a supply valve 83b is provided in supply pipe 82b. Supply valve 83a switches the opening and closing of supply pipe 82a, and supply valve 83b switches the opening and closing of supply pipe 82a. In addition, flow control valves and flow meters may be provided in supply pipes 82a and 82b.

[0067] The control unit 9 controls various configurations of the processing unit 1. The control unit 9 includes, for example, a data processing unit and a storage unit. The data processing unit is, for example, a central processing unit (CPU). The storage unit includes, for example, a volatile storage unit such as RAM (Random Access Memory) and a non-volatile storage unit such as ROM (Read Only Memory). In addition, a non-volatile storage unit including a hard disk and various types of memory may be provided separately outside the control unit 9. The control unit 9 can realize the various functions described later by executing software stored in the non-volatile storage unit. The control unit 9 may also include dedicated hardware circuits that realize some or all of the various functions described later.

[0068] As shown in Figure 3, the control unit 9 includes a holding control unit 91, a brush control unit 92, an adhesion determination unit 93, a liquid supply control unit 94, and a brush cleaning control unit 95.

[0069] The holding control unit 91 controls the substrate holding unit 2. For example, the holding control unit 91 controls the pin drive unit of the substrate holding unit 2 to switch between holding and releasing the substrate W. The holding control unit 91 also controls the rotation drive unit 23 of the substrate holding unit 2 to control the rotation speed of the substrate W.

[0070] The brush control unit 92 controls the brush movement drive unit 410 and the brush drive unit 401. For example, the brush control unit 92 controls the brush movement drive unit 410 to move the brush 4. The brush control unit 92 also controls the brush drive unit 401 to control the rotation speed of the brush 4.

[0071] The liquid supply control unit 94 controls supply valves 33a and 33b. When the liquid supply control unit 94 opens supply valve 33a, the chemical solution is discharged from the chemical solution nozzle 31. Also, when the liquid supply control unit 94 opens supply valve 33b, the rinsing solution is discharged from the chemical solution nozzle 31. The liquid supply control unit 94 also controls flow rate adjustment valves 34a and 34b. For example, the liquid supply control unit 94 controls flow rate adjustment valve 34a based on the measurement result of flow meter 35a, and controls flow rate adjustment valve 34b based on the measurement result of flow meter 35b.

[0072] The brush cleaning control unit 95 controls the supply valves 83a and 83b. When the brush cleaning control unit 95 opens the supply valve 83a, it discharges cleaning fluid from the first cleaning nozzle 81a, and when it opens the supply valve 83b, it discharges cleaning fluid from the second cleaning nozzle 81b. Furthermore, if flow rate control valves are provided in the supply pipes 82a and 82b, the brush cleaning control unit 95 can appropriately control the flow rate control valves provided in the supply pipes 82a and 82b.

[0073] The adhesion detection unit 6 detects the adhesion of the chemical solution to the brush holding unit 5. In the example shown in Figure 3, the adhesion detection unit 6 includes a flow meter 35a, a brush control unit 92, and an adhesion determination unit 93. The operation of the adhesion detection unit 6 will be described in detail later.

[0074] <An example of substrate processing> Next, an example of processing on the substrate W by the processing unit 1 will be described. Figure 5 is a flowchart showing an example of the operation of the processing unit 1. The control unit 9 causes the processing unit 1 to execute the processing from step S1 to step S5 according to a pre-set processing procedure (recipe).

[0075] First, a transport robot transports the substrate W to the processing unit 1. Then, the substrate holding unit 2 holds the substrate W received from the transport robot (step S1: holding process). As a specific example, the substrate holding unit 2 displaces multiple chuck pins 22 from their respective release positions to holding positions. As a result, the multiple chuck pins 22 hold the substrate W. The substrate holding unit 2 continues to hold the substrate W until the processing of the substrate W is completed.

[0076] Next, the processing unit 1 performs scrubber cleaning on the substrate W (step S2: scrubber cleaning process). Specifically, the substrate holding unit 2 rotates the substrate W around the rotation axis Q1, and the chemical nozzle 31 discharges the chemical solution toward the main surface of the substrate W, while the brush movement drive unit 410 moves the brush 4 to the processing position. The discharge of the chemical solution is performed by the control unit 9 opening the supply valve 33a. The flow rate of the chemical solution is set in advance to, for example, several hundred cc / min, and as a more specific example, it is set to about 400 cc / min.

[0077] Figure 6 schematically shows the time evolution of the processing unit 1 during scrubber cleaning. In the example shown in Figure 6, the brush movement drive unit 410 lowers the brush 4 from a position directly above the central position Pb1 of the substrate W, bringing the brush 4 into contact with the main surface of the substrate W at the central position Pb1. The central position Pb1 is predetermined, and as a more specific example, it is the position where the center of the lower surface 4a of the brush 4 faces the center of the substrate W.

[0078] In the example in Figure 6, the chemical solution discharged toward the main surface of the substrate W is schematically shown in the sandy area. The chemical solution lands on the main surface of the substrate W at the landsing position Pc. The landsing position Pc is closer to the discharge port 3a of the chemical solution nozzle 31 than to the brush holding part 5 (see also Figure 2). The distance between the landsing position Pc and the rotation axis Q1 may be, for example, less than or equal to half the radius of the substrate W, or less than or equal to one-third. The chemical solution that lands at the landsing position Pc spreads around the landsing position Pc, and, due to the centrifugal force accompanying the rotation of the substrate W, flows radially outward and scatters outward from the periphery of the substrate W. In this way, the chemical solution is supplied to the entire main surface of the substrate W. Note that in Figure 6, the illustration of the chemical solution on the main surface of the substrate W is omitted.

[0079] In the example in Figure 6, the chemical solution that collides with the brush holder 5 is shown in the sandy area enclosed by the dashed line. Such collisions of the chemical solution with the brush holder 5 can occur, for example, due to an abnormal flow rate. In other words, a malfunction in the flow control valve 34a or the like causes an excessive flow rate of chemical solution to be discharged from the chemical solution nozzle 31, causing the chemical solution to travel a longer distance through the air and, as a result, to collide with the brush holder 5 before it can settle on the main surface of the substrate W. Various processes related to this collision of the chemical solution with the brush holder 5 will be described later. Below, we will first describe the case where the flow rate is normal and the chemical solution settles on the main surface of the substrate W at the settling position Pc. In other words, the settling position Pc is the settling position on the main surface of the substrate W when the chemical solution is discharged normally.

[0080] During scrubber cleaning, the brush movement drive unit 410 moves the brush 4 from the central position Pb1 to the peripheral position Pb2 along the main surface of the substrate W while the brush 4 is in contact with the main surface of the substrate W. The peripheral position Pb2 is, for example, predetermined and is radially outside the central position Pb1. As a more specific example, the peripheral position Pb2 may be a position where the radially outer edge of the lower surface 4a of the brush 4 coincides with the periphery of the substrate W, or is radially outside the periphery of the substrate W. The movement time from the central position Pb1 to the peripheral position Pb2 is also predetermined and may be set to, for example, several tens of seconds. The brush movement drive unit 410 moves the brush 4 from the central position Pb1 to the peripheral position Pb2 within the set movement time. In the following, the range from the central position Pb1 to the peripheral position Pb2 will also be referred to as the movement range R.

[0081] The brush drive unit 401 may rotate the brush 4 around the rotation axis Q2 at least while the brush 4 is moving from the central position Pb1 to the peripheral position Pb2. The brush drive unit 401 may also press the brush 4 toward the main surface of the substrate W with a preset pressing force.

[0082] When the brush 4 reaches the peripheral position Pb2, the brush drive unit 401 stops the rotation of the brush 4, and the brush movement drive unit 410 raises the brush 4. Then, the brush movement drive unit 410 moves the brush 4 to the standby pod 7. The control unit 9 also closes the supply valve 33a to stop the discharge of the chemical solution from the chemical solution nozzle 31. An example of the inside of the processing unit 1 enclosed in parentheses in Figure 6 will be described later.

[0083] In this way, during scrubber cleaning, the brush 4 moves along the rotating main surface of the substrate W while the cleaning solution is supplied to the main surface of the substrate W. This allows the lower surface 4a of the brush 4 to rub against the main surface of the substrate W, thereby cleaning the main surface of the substrate W. As the brush 4 moves from the central position Pb1 to the peripheral position Pb2, the entire main surface of the substrate W can be cleaned.

[0084] Next, the processing unit 1 supplies rinsing liquid to the main surface of the substrate W (step S3: rinsing process). Specifically, the control unit 9 opens the supply valve 33b. As a result, rinsing liquid is discharged from the chemical nozzle 31 toward the main surface of the rotating substrate W. The rinsing liquid that lands in the center of the main surface of the substrate W is carried radially outward by the centrifugal force accompanying the rotation of the substrate W and splashes from the periphery of the substrate W. At this time, the rinsing liquid pushes the chemical solution on the main surface of the substrate W radially outward. As a result, the processing liquid on the main surface of the substrate W is replaced from the chemical solution to the rinsing liquid.

[0085] When the replacement of the chemical solution with the rinsing solution is sufficient, the control unit 9 closes the supply valve 33b. As a specific example, the control unit 9 measures the elapsed time from the start of rinsing solution discharge, and when this elapsed time exceeds a predetermined rinsing time, it switches the supply valve 33b from the open state to the closed state. The rinsing time is pre-set to a time sufficient for the replacement of the chemical solution with the rinsing solution to occur.

[0086] Next, the processing unit 1 dries the substrate W (step S4: drying process). More specifically, the substrate holding unit 2 increases the rotation speed of the substrate W (so-called spin drying). When the substrate W is sufficiently dry, the substrate holding unit 2 stops the rotation of the substrate W. As a specific example, the control unit 9 measures the elapsed time since the discharge of the rinsing liquid stopped and determines whether the measured time is equal to or greater than a predetermined drying time. The drying time is set in advance to a time sufficient for the substrate W to be sufficiently dry. When the elapsed time is equal to or greater than the drying time, the substrate holding unit 2 stops the rotation of the substrate W.

[0087] Next, the substrate holding unit 2 releases its grip on the substrate W (Step S5: Release step). Then, the transport robot unloads the processed substrate W from the processing unit 1.

[0088] Unprocessed substrates W are sequentially transported to the processing unit 1, and steps S1 to S5 are executed each time, with processed substrates W being sequentially discharged from the processing unit 1. This allows for sequential processing of multiple substrates W.

[0089] Incidentally, as mentioned above, there is a possibility that the chemical solution may collide with the brush holder 5 during scrubber cleaning. If the chemical solution adheres to the brush holder 5, it may fall from the brush holder 5 onto the main surface of the substrate W at an unintended timing during the next processing of the substrate W. This may result in partial and unnecessary chemical treatment of the main surface of the substrate W.

[0090] Here, we will first explain an example of the positional relationship between the chemical nozzle 31 and the brush holder 5. Figure 7 is a diagram illustrating the positional relationship between the chemical nozzle 31 and the brush holder 5. In the example in Figure 7, a hypothetical straight line along the direction of chemical discharge at the discharge port 3a of the chemical nozzle 31 is shown as the straight line VL1. Immediately after the discharge port 3a of the chemical nozzle 31, the chemical moves through the air in a trajectory along the straight line VL1, but due to gravity, the chemical shifts downward from the straight line VL1 as it moves away from the discharge port 3a (see also Figure 1). The larger the flow rate of the chemical, the higher the flow velocity, so the trajectory of the chemical will follow the straight line VL1 for a longer distance.

[0091] In the example in Figure 7, a hypothetical plane VP is also shown, obtained by extending the movement range R of the brush holder 5 in the vertical direction during scrubber cleaning. The hypothetical straight line VL1 intersects plane VP at a position higher than the lower end of the brush holder 5. In the example in Figure 7, the straight line VL1 intersects the brush holder 5 located at the central position Pb1. In this positional relationship, if the chemical solution is discharged from the chemical nozzle 31 at a very large flow rate, the chemical solution may collide with the brush holder 5 before reaching the main surface of the substrate W. In other words, due to the abnormal flow rate, the chemical solution may travel along the straight line VL1 for a relatively long distance from the discharge port 3a of the chemical nozzle 31, and as a result, it may collide with the brush holder 5 located near the central position Pb1.

[0092] Referring to Figure 2, the trajectory of the chemical solution from the discharge port 3a of the chemical solution nozzle 31 to the main surface of the substrate W follows a hypothetical straight line VL1 in a plan view. This hypothetical straight line VL1 intersects with a hypothetical straight line VL2, which follows the movement trajectory of the brush 4 on the main surface of the substrate W. Specifically, straight line VL1 intersects with straight line VL2 at the center of the substrate W. In this case, when the brush 4 is located near the central position Pb1, the chemical solution may collide with the brush holding part 5 due to a flow rate anomaly. On the other hand, when the brush 4 is far from the central position Pb1, the chemical solution will not collide with the brush holding part 5 even if a flow rate anomaly occurs. In other words, when the brush 4 is located within a predetermined range Rb that includes the central position Pb1, the chemical solution may collide with the brush holding part 5 due to a flow rate anomaly, but when the brush 4 is located outside the predetermined range Rb, the chemical solution will not collide with the brush holding part 5. Here, the predetermined range Rb is the range that includes the central position Pb1 and is predetermined by experiment or simulation, etc. Furthermore, the predetermined range Rb can be described as the range of positions of the brush 4 in which the chemical solution can collide with the brush holding part 5.

[0093] Conversely, if an abnormal flow rate occurs and the brush 4 is located within the predetermined range Rb, it can be assumed that the chemical solution is colliding with the brush holding part 5.

[0094] Therefore, the adhesion detection unit 6 detects the adhesion of the chemical solution to the brush holding unit 5 based on the flow rate of the chemical solution measured by the flow meter 35a and the brush position of the brush 4 acquired by the brush position acquisition unit, which will be described next. The brush position acquisition unit may be a function of the control unit 9. In other words, the control unit 9 controls the brush movement drive unit 410 to control the brush position of the brush 4. For this reason, the control unit 9 can grasp the brush position of the brush 4. Specifically, the brush control unit 92 of the control unit 9 can grasp the brush position of the brush 4 and can therefore function as a brush position acquisition unit.

[0095] The brush position acquisition unit does not necessarily have to be a function of the brush control unit 92 of the control unit 9. For example, a sensor for measuring the brush position of the brush 4 may be provided in the processing unit 1. As a specific example, a rotary encoder for measuring the rotational position of the motor of the brush movement drive unit 410 may be provided. The control unit 9 may calculate the brush position of the brush 4 based on the measurement result of the rotary encoder.

[0096] The adhesion detection unit 6 determines that the chemical solution is colliding with the brush holding unit 5 when the flow rate of the chemical solution is above a predetermined flow rate threshold and the brush 4 is located within a predetermined range Rb. In other words, the adhesion detection unit 6 detects the adhesion of the chemical solution to the brush holding unit 5.

[0097] When the adhesion detection unit 6 detects that the chemical solution has adhered to the brush holding unit 5, the control unit 9 determines that the brush holding unit 5 needs to be cleaned, and when the brush movement drive unit 410 moves the brush 4 to the standby pod 7, it controls the cleaning solution supply unit 8 to clean the brush holding unit 5 with cleaning solution.

[0098] Here, the operations related to brush cleaning described above will be explained in more detail with reference to the flowchart. Figure 8 is a flowchart of an example of the operations related to brush cleaning by the processing unit 1. In the example in Figure 8, when scrubber cleaning (step S2) is started (step S11), the processing unit 1 executes steps S12 to S15, which will be described later. In other words, steps S12 to S15 are executed in parallel with scrubber cleaning (step S2). First, the flow meter 35a measures the flow rate of the chemical solution (step S12: flow rate measurement step). Then, the flow meter 35a outputs an electrical signal indicating the measurement result to the control unit 9. Next, the brush position acquisition unit (here, the control unit 9, specifically the brush control unit 92) acquires the brush position of the brush 4 (step S13: brush position acquisition step). Note that the execution order of steps S12 and S13 may be reversed.

[0099] Next, the adhesion determination unit 93 determines whether or not the chemical solution has adhered to the brush holding unit 5 based on the flow rate measured by the flow meter 35a and the brush position of the brush 4 acquired by the brush position acquisition unit (step S14: determination step). Specifically, the adhesion determination unit 93 determines that the chemical solution has adhered to the brush holding unit 5 when the flow rate is equal to or greater than the flow rate threshold and the brush 4 is located within a predetermined range Rb. Conversely, the adhesion determination unit 93 determines that the chemical solution has not adhered to the brush holding unit 5 even if the flow rate is equal to or greater than the flow rate threshold, if the brush 4 is outside the predetermined range Rb. Also, the adhesion determination unit 93 determines that the chemical solution has not adhered to the brush holding unit 5 when the flow rate is less than the flow rate threshold, regardless of the brush position of the brush 4. The flow rate threshold and the predetermined range Rb are set in advance, for example, by experiment or simulation. The flow rate threshold may be set to, for example, about 430 cc / min.

[0100] When the adhesion detection unit 93 determines that the chemical solution has adhered to the brush holding unit 5, the control unit 9 determines that the brush holding unit 5 needs to be cleaned (step S15). For example, the control unit 9 stores a cleaning flag in the storage unit. More specifically, the control unit 9 sets the cleaning flag to an activated state (e.g., H (high) state) and stores the cleaning flag in the storage unit.

[0101] Next, the control unit 9 determines whether or not the scrubber cleaning is complete (step S16). If the scrubber cleaning is not yet complete, the processing unit 1 executes step S12 again.

[0102] In step S14, if the adhesion determination unit 93 determines that no liquid chemical is adhering to the brush holding unit 5, the control unit 9 proceeds to step S16 without performing step S15.

[0103] As described above, the processing unit 1 repeatedly executes the series of processes from step S12 to step S15 until the scrubber cleaning is completed. Therefore, if the adhesion detection unit 6 detects the adhesion of the chemical solution to the brush holding unit 5 even once during scrubber cleaning, the control unit 9 determines that cleaning of the brush holding unit 5 is necessary.

[0104] Once the scrubber cleaning is complete, the control unit 9 determines whether or not it has determined that cleaning of the brush holder 5 is necessary (step S17). For example, the control unit 9 determines whether or not a cleaning flag is stored in the memory unit. As a more specific example, the control unit 9 determines whether or not the cleaning flag is in an active state. If the cleaning flag is in an active state, the control unit 9 performs a first brush cleaning to clean the brush holder 5 (step S18: first brush cleaning step).

[0105] In the first brush cleaning, the cleaning fluid supply unit 8 cleans the brush holder 5 using cleaning fluid. For example, the control unit 9 opens both the supply valve 83a and the supply valve 83b while the brush 4 is housed in the standby pod 7. As a result, cleaning fluid is discharged from the discharge port 8a of the first cleaning nozzle 81a toward the brush holder 5, while cleaning fluid is discharged from the discharge port 8b of the second cleaning nozzle 81b toward the brush 4 (see also Figure 4). The flow rate of the cleaning fluid discharged from the first cleaning nozzle 81a is set to several hundred cc / min, for example, and can be set to about 150 cc / min as a specific example. The flow rate of the cleaning fluid discharged from the second cleaning nozzle 81b is also set to several hundred cc / min, for example, and can be set to about 150 cc / min as a specific example.

[0106] In the example shown in Figure 4, the cleaning liquid discharged from the first cleaning nozzle 81a lands on the upper surface of the brush holder 5, overflows from the upper surface of the brush holder 5, and flows down along the side surface of the brush holder 5. As a result, any chemical solution adhering to the brush holder 5 flows down with the cleaning liquid, cleaning the brush holder 5. In addition, the cleaning liquid discharged from the second cleaning nozzle 81b collides with the lower surface 4a of the brush 4. This allows the lower surface 4a of the brush 4 to be cleaned. Furthermore, drying of the brush 4 can be suppressed. Although the brush 4 can harden if it dries, the first brush cleaning described above can prevent the brush 4 from hardening. Therefore, in the subsequent scrubber cleaning of the substrate W, damage to the main surface of the substrate W by the brush 4 can be suppressed.

[0107] In the first brush cleaning, the brush drive unit 401 may rotate the brush 4 around the rotation axis Q2. This allows the cleaning fluid supply unit 8 to uniformly supply cleaning fluid over the entire surface of the side of the brush holding unit 5. Similarly, the cleaning fluid supply unit 8 can uniformly supply cleaning fluid over the entire surface of the lower surface 4a of the brush 4.

[0108] When the first brush cleaning is performed, the control unit 9 erases the cleaning flag from the memory. Specifically, the control unit 9 sets the cleaning flag to an inactive state (for example, a low state).

[0109] Furthermore, if the control unit 9 determines in step S17 that cleaning of the brush holding part 5 is unnecessary, the control unit 9 performs a second brush cleaning (step S19: second brush cleaning step). In the second brush cleaning, the cleaning liquid supply unit 8 cleans the lower surface 4a of the brush 4 with cleaning liquid without cleaning the brush holding part 5. For example, with the brush 4 stored in the standby pod 7, the control unit 9 opens the supply valve 83b while keeping the supply valve 83a closed. As a result, no cleaning liquid is discharged from the first cleaning nozzle 81a, and cleaning liquid is discharged from the second cleaning nozzle 81b toward the lower surface 4a of the brush 4. This makes it possible to clean the lower surface 4a of the brush 4 while suppressing the drying of the brush 4.

[0110] As described above, in this embodiment, the adhesion detection unit 6 detects the adhesion of the chemical solution to the brush holding unit 5. The control unit 9 then determines, in response to this detection, that cleaning of the brush holding unit 5 is necessary. Therefore, the processing unit 1 can perform cleaning of the brush holding unit 5 (i.e., first brush cleaning) when there is a high probability that cleaning of the brush holding unit 5 is necessary. Conversely, the processing unit 1 can avoid performing cleaning of the brush holding unit 5 when there is a high probability that cleaning of the brush holding unit 5 is unnecessary. This reduces the running cost of the processing unit 1. Specifically, in the above example, when there is a high probability that cleaning of the brush holding unit 5 is unnecessary, the cleaning solution is not discharged from the first cleaning nozzle 81a (second brush cleaning). This reduces the amount of cleaning solution used. Therefore, the processing unit 1 according to this embodiment contributes to saving cleaning solution.

[0111] Furthermore, in the example described above, the adhesion detection unit 6 detects the adhesion of the chemical solution to the brush holding unit 5 based not only on the flow rate of the chemical solution but also on the brush position. Therefore, the adhesion detection unit 6 can detect the adhesion of the chemical solution with higher accuracy.

[0112] Furthermore, in the example described above, the cleaning fluid supply unit 8 includes a first cleaning nozzle 81a and a second cleaning nozzle 81b. Therefore, the cleaning fluid supply unit 8 can reliably supply cleaning fluid to the brush holding unit 5 and the brush 4 during the first brush cleaning.

[0113] <First brush cleaning> Next, we will describe another specific example of the first brush cleaning. Figure 9 is a timing chart showing an example of the operation of the processing unit 1 during the first brush cleaning. Figure 9 shows the brush cleaning time T during which the first brush cleaning is performed. In the example of Figure 9(a), both the supply valve 83a and the supply valve 83b are opened during the initial first time T1 of the brush cleaning time T. As a result, during the first time T1, cleaning fluid is discharged from the first cleaning nozzle 81a toward the brush holder 5, while cleaning fluid is discharged from the second cleaning nozzle 81b toward the brush 4. Therefore, during the first time T1, the cleaning fluid supply unit 8 cleans both the brush holder 5 and the brush 4. The first time T1 is pre-set to a time sufficient to adequately clean the brush holder 5, and as a more specific example, it may be set to about 10 to 15 seconds.

[0114] In the example shown in Figure 9(a), at the second time T2, the supply valve 83a closes and the supply valve 83b opens. The second time T2 is a time after the first time T1, and in the example shown in Figure 9(a), it is a time continuous with the first time T1. Since the supply valve 83a closes and the supply valve 83b opens at the second time T2, the first cleaning nozzle 81a does not discharge cleaning fluid, and the cleaning fluid is discharged from the second cleaning nozzle 81b toward the brush 4. Therefore, at the second time T2, the cleaning fluid supply unit 8 cleans the brush 4 without cleaning the brush holding unit 5.

[0115] Furthermore, in the example shown in Figure 9(b), at the first time T1, the supply valve 83a is open and the supply valve 83b is closed. As a result, cleaning fluid is discharged from the first cleaning nozzle 81a toward the brush holding section 5, but the second cleaning nozzle 81b does not discharge cleaning fluid. Therefore, the cleaning fluid supply unit 8 cleans the brush holding section 5. Note that the cleaning fluid can flow from the brush holding section 5 toward the brush 4. Therefore, at the first time T1, the cleaning fluid supply unit 8 can partially clean the brush 4 while also suppressing the drying of the brush 4.

[0116] In the example shown in Figure 9(b), during the second time T2, the supply valve 83a closes and the supply valve 83b opens. As a result, during the second time T2, the first cleaning nozzle 81a does not discharge cleaning fluid, and the cleaning fluid is discharged from the second cleaning nozzle 81b toward the brush 4. Therefore, during the second time T2, only the brush 4 is cleaned.

[0117] As described above, in the example of Figure 9, the supply valve 83a opens at the first time T1 and closes at the second time T2. Therefore, the amount of cleaning fluid used can be reduced compared to the case where the supply valve 83a is open at both the first time T1 and the second time T2. In addition, the supply valve 83b is open at least at the second time T2. Therefore, drying of the brush 4 can be appropriately suppressed. If the supply valve 83b is closed at least for a portion of the first time T1, the amount of cleaning fluid used can be further reduced.

[0118] <Scrubber cleaning> Next, other examples of the specific operation of scrubber cleaning will be described. In the example above, the brush 4 moves only once from the central position Pb1 to the peripheral position Pb2 during scrubber cleaning, but it may move multiple times. Referring to Figure 6, for example, the brush movement drive unit 410 may raise the brush 4 from the peripheral position Pb2 and move the brush 4 toward a position directly above the central position Pb1. The brush movement drive unit 410 then lowers the brush 4 from that position back to the central position Pb1. Then, the brush movement drive unit 410 may move the brush 4 from the central position Pb1 to the peripheral position Pb2. The brush movement drive unit 410 may repeat the same operation. This allows the processing unit 1 to more reliably clean the main surface of the substrate W.

[0119] Even while the brush 4 is moving from a position directly above the peripheral position Pb2 to a position directly above the central position Pb1, the chemical solution can collide with the brush holding part 5. In other words, if the distance D between the lower surface 4a of the brush 4 and the main surface of the substrate W is shorter than a predetermined distance, the chemical solution can collide with the brush holding part 5 due to an abnormal flow rate if the brush 4 is located within a predetermined range Rb in a plan view. For this reason, the adhesion determination unit 93 may determine that the chemical solution is adhering to the brush holding part 5 when the flow rate of the chemical solution is above the flow rate threshold, the distance D is below the predetermined distance, and the position of the brush 4 in a plan view is within the predetermined range Rb. The predetermined distance is set in advance, for example, by experiment or simulation.

[0120] Furthermore, in the example described above, the brush movement drive unit 410 moves the brush 4 by the radius of the substrate W from the central position Pb1 to the peripheral position Pb2, but the movement range R can be changed as appropriate. For example, the brush movement drive unit 410 may move the brush 4 by the diameter of the substrate W. In other words, the brush movement drive unit 410 may move the brush 4 from the peripheral position on one end of the diameter of the substrate W to the peripheral position Pb2 on the other end.

[0121] <Method for detecting adhesion> Next, another example of the adhesion detection method will be described. The adhesion detection unit 6 may detect the adhesion of the chemical solution to the brush holding unit 5 based solely on the flow rate of the chemical solution. As a more specific example, in scrubber cleaning, the adhesion determination unit 93 may determine that the chemical solution has adhered to the brush holding unit 5 when the flow rate measured by the flow meter 35a is equal to or greater than a predetermined flow rate threshold. If the abnormal flow rate continues for a long period of time, the chemical solution will continue to adhere to a position deeper than the contact point Pc. Therefore, in scrubber cleaning of each substrate W, the chemical solution collides with the brush holding unit 5 each time the brush 4 enters the predetermined range Rb. In other words, if the abnormal chemical solution continues, the brush 4 will eventually move into the predetermined range Rb, and at that time the chemical solution will collide with the brush holding unit 5. Therefore, the adhesion determination unit 93 may determine that the chemical solution has adhered to the brush holding unit 5, triggered by the condition that the chemical solution is equal to or greater than the flow rate threshold. Even with such a determination method, the adhesion detection unit 6 can detect the adhesion of the chemical solution to the brush holding unit 5 with a certain degree of accuracy.

[0122] <Second Embodiment> Figure 10 is a plan view showing an example of the configuration of processing unit 1A according to the second embodiment, and Figure 11 is a schematic diagram showing an example of the configuration of the standby pod 7, part of the cleaning fluid supply unit 8, brush 4, and brush holding unit 5 according to the second embodiment. Processing unit 1A differs from processing unit 1 in that it has a configuration of the cleaning fluid supply unit 8.

[0123] In the second embodiment, the cleaning fluid supply unit 8 includes a single cleaning nozzle 81, a supply pipe 82, and a supply valve 83. The cleaning nozzle 81, supply pipe 82, and supply valve 83 are the same as those of the first cleaning nozzle 81a, supply pipe 82a, and supply valve 83a, respectively.

[0124] An example of the operation of the processing unit 1A is shown in Figures 5 and 8. However, the specific operation of the first brush cleaning differs. In the second embodiment, the control unit 9 performs the following processes during the first brush cleaning: raising and lowering the brush 4 using the brush movement drive unit 410 to bring the brush 4 into contact with the cleaning fluid, and bringing the cleaning fluid into contact with the brush holding unit 5. As a more specific example, the brush movement drive unit 410 raises and lowers the brush 4 between an upper position and a lower position in the standby pod 7. The upper position is the position where the cleaning fluid discharged from the cleaning nozzle 81 lands on the brush 4 (specifically, the lower surface 4a). In the example in Figure 11, the brush 4 and brush holding unit 5 located in the upper position are shown by solid lines. The lower position is the position where the cleaning fluid discharged from the cleaning nozzle 81 lands on the brush holding unit 5 (specifically, the upper surface).

[0125] Specifically, the brush movement drive unit 410 first moves the brush 4 directly above the standby pod 7. Then, for example, with the control unit 9 open the supply valve 83, that is, with the cleaning nozzle 81 discharging cleaning fluid, the brush movement drive unit 410 moves the brush 4 to the lower position. As a result, the cleaning fluid collides sequentially with the lower surface 4a of the brush 4 and the vertically upper portion of the brush 4. Then, as the brush 4 descends, the cleaning fluid collides with the lower end of the brush holder 5, and then sequentially with the vertically upper portion from that lower end. In other words, as the brush 4 descends from the upper position to the lower position, the collision point of the cleaning fluid moves from the lower surface 4a of the brush 4 to the upper surface of the brush holder 5. When the brush 4 reaches the lower position, the cleaning fluid lands on the upper surface of the brush holder 5.

[0126] The brush movement drive unit 410 then stops the brush 4 in the lower position for a predetermined time sufficient to clean the brush holder 5. After the predetermined time has elapsed, the brush movement drive unit 410 begins to move the brush 4 to the upper position. As the brush 4 rises from the lower position to the upper position, the point of impact of the cleaning liquid moves from the upper surface of the brush holder 5 to the lower surface 4a of the brush 4. When the brush 4 reaches the upper position, the brush movement drive unit 410 stops the brush 4. As a result, cleaning liquid is discharged from the cleaning nozzle 81 toward the lower surface 4a of the brush 4, cleaning the lower surface 4a of the brush 4 and preventing the brush 4 from drying out.

[0127] In this first brush cleaning, the brush drive unit 401 may rotate the brush 4 around the rotation axis Q2. This allows the cleaning fluid supply unit 8 to supply the cleaning fluid more uniformly to the entire brush 4 and brush holding unit 5.

[0128] On the other hand, during the second brush cleaning, the brush movement drive unit 410 stops the brush 4 in the upper position. Then, the cleaning nozzle 81 discharges cleaning fluid to clean the lower surface 4a of the brush 4 and suppress the drying of the brush 4. In other words, during the second brush cleaning, the brush movement drive unit 410 does not move the brush 4 back and forth between the upper and lower positions.

[0129] The brush drive unit 401 may also rotate the brush 4 around the rotation axis Q2 during the second brush cleaning. This allows the cleaning fluid supply unit 8 to supply the cleaning fluid more uniformly to the entire lower surface 4a of the brush 4.

[0130] In the second embodiment as well, the processing unit 1A performs a first brush cleaning when the adhesion detection unit 6 detects the adhesion of the chemical solution to the brush holding unit 5, and performs a second brush cleaning when the adhesion detection unit 6 does not detect the adhesion of the chemical solution to the brush holding unit 5. Therefore, when there is a high probability that no chemical solution is present, the processing unit 1A does not perform the reciprocal movement of the brush 4 between the upper and lower positions during the first brush cleaning. Consequently, the processing unit 1A can avoid unnecessary first brush cleaning, thereby reducing running costs.

[0131] Furthermore, according to the second embodiment, the cleaning fluid supply unit 8 does not need to include multiple cleaning nozzles 81, but includes a single cleaning nozzle 81. Therefore, the cleaning fluid supply unit 8 can be configured with a simpler structure.

[0132] In the example described above, the brush movement drive unit 410 lowered the brush 4 from the upper position to the lower position while the cleaning nozzle 81 was discharging cleaning fluid. As a result, the cleaning fluid began to collide with the brush 4. However, this is not necessarily the only option. For example, the brush movement drive unit 410 may lower the brush 4 to the lower position while the cleaning nozzle 81 is not discharging cleaning fluid, and then the cleaning nozzle 81 may discharge cleaning fluid. In this case, the cleaning fluid is first supplied to the upper surface of the brush holding unit 5. Then, after a predetermined time has elapsed, the brush movement drive unit 410 may raise the brush 4 from the lower position to the upper position while the cleaning nozzle 81 is discharging cleaning fluid. This also allows for cleaning of the brush holding unit 5 while also cleaning the lower surface 4a of the brush 4. Furthermore, since no cleaning fluid is supplied while the brush 4 is descending to the lower position, the amount of cleaning fluid used can be reduced.

[0133] Furthermore, although the cleaning nozzle 81 discharges cleaning fluid toward the brush 4 and brush holder 5 in the above example, this is not necessarily the case. For example, a dish-shaped reservoir for storing cleaning fluid may be provided at the bottom of the standby pod 7, and the cleaning nozzle 81 may discharge cleaning fluid toward the reservoir. Alternatively, the cleaning nozzle 81 may not be provided, and the downstream end of the supply pipe 82 may be connected to the reservoir. In this case, the downstream port of the supply pipe 82 corresponds to the discharge port. In this case, cleaning fluid can be supplied to the reservoir from the discharge port of the supply pipe 82. Also, in this case, the upper position is the position where the brush 4 is immersed in the cleaning fluid in the reservoir, but the brush holder 5 is not immersed in the cleaning fluid, and the lower position is the position where both the brush 4 and the brush holder 5 are immersed in the cleaning fluid in the reservoir. The brush movement drive unit 410 can bring the brush 4 into contact with the cleaning fluid by moving the brush 4 to the upper position, and can bring the brush 4 and the brush holder 5 into contact with the cleaning fluid by moving the brush 4 to the lower position.

[0134] <Third Embodiment> Figure 12 is a schematic plan view showing an example of the configuration of processing unit 1B according to the third embodiment. Processing unit 1B differs from processing unit 1 in that it has a nozzle displacement drive unit 36. The nozzle displacement drive unit 36 ​​displaces the chemical nozzle 31 to move the liquid application position Pc on the main surface of the substrate W. In the example in Figure 12, the nozzle displacement drive unit 36 ​​rotates (oscillates) the chemical nozzle 31 in forward and reverse directions in the horizontal plane around its base end. In this case, the nozzle position of the chemical nozzle 31 can be shown as the rotational position (angle) around the base end. In the example in Figure 12, the chemical nozzle 31 when the chemical is applied to the application position Pc(t0) is shown by a solid line, and the chemical nozzle 31 when the chemical is applied to the application position Pc(tn) is shown by a dashed line. As the chemical nozzle 31 is displaced, the application position Pc moves continuously from the application position Pc(t0) to the application position Pc(tn). The nozzle displacement drive unit 36 ​​has a drive source such as a motor and an air cylinder.

[0135] Figure 13 is a schematic block diagram showing an example of the electrical configuration of the processing unit 1B according to the third embodiment. The control unit 9 according to the third embodiment further includes a nozzle displacement control unit 96. The nozzle displacement control unit 96 controls the nozzle displacement drive unit 36 ​​to control the nozzle position of the chemical nozzle 31. Specifically, in scrubber cleaning, the chemical nozzle 31 is moved between the first nozzle position and the nth nozzle position, which will be described below. The first nozzle position is the rotational position when the chemical nozzle 31 is facing the liquid application position Pc(t0). The nth nozzle position is the rotational position when the chemical nozzle 31 is facing the liquid application position Pc(tn). As a result, the processing unit 1B can supply the chemical solution more uniformly to the main surface of the substrate W during scrubber cleaning.

[0136] On the other hand, if the liquid application position Pc moves according to the nozzle position of the liquid solution nozzle 31, the predetermined range Rb in which the liquid solution can collide with the brush holding part 5 also changes according to the nozzle position. For example, if a flow rate abnormality occurs when the liquid solution nozzle 31 is in the first nozzle position, the liquid solution will reach further than the liquid application position Pc(t0). Therefore, the liquid solution may collide with the brush holding part 5 located within the predetermined range Rb(t0). Conversely, when the liquid solution nozzle 31 is facing the liquid application position Pc(t0), if the brush 4 is located outside the predetermined range Rb(t0), the liquid solution will not collide with the brush holding part 5. The predetermined range Rb(t0) is the range in which the liquid solution can collide with the brush holding part 5 when the liquid solution nozzle 31 is in the first nozzle position, and is set in advance, for example, by experiment or simulation.

[0137] Similarly, if a flow rate anomaly occurs when the chemical nozzle 31 is in the nth nozzle position, the chemical will reach further than the application position Pc(tn). As a result, the chemical may collide with the brush holding part 5 located within a predetermined range Rb(tn). Conversely, when the chemical nozzle 31 is facing the application position Pc(tn), the chemical will not collide with the brush holding part 5 if the brush 4 is outside the predetermined range Rb(tn). The predetermined range Rb(tn) is the range in which the chemical may collide with the brush holding part 5 when the chemical nozzle 31 is in the nth nozzle position, and is predetermined, for example, by experimentation or simulation.

[0138] As described above, in the third embodiment, whether or not the liquid chemical collides with the brush holding part 5 depends not only on the flow rate of the liquid chemical and the brush position of the brush holding part 5, but also on the nozzle position of the liquid chemical nozzle 31.

[0139] Therefore, in the third embodiment, the adhesion detection unit 6 detects the adhesion of the chemical solution to the brush holding unit 5 based on the flow rate of the chemical solution measured by the flow meter 35a, the brush position of the brush holding unit 5 acquired by the brush position acquisition unit, and the nozzle position of the chemical solution nozzle 31 acquired by the nozzle position acquisition unit, which will be described next. The nozzle position acquisition unit may be, for example, a function of the control unit 9. In other words, the control unit 9 controls the nozzle position of the chemical solution nozzle 31 by controlling the nozzle displacement drive unit 36. For this reason, the control unit 9 can grasp the nozzle position of the chemical solution nozzle 31. Specifically, the nozzle displacement control unit 96 of the control unit 9 can grasp the nozzle position of the chemical solution nozzle 31 and can therefore function as a nozzle position acquisition unit.

[0140] Alternatively, a sensor for measuring the nozzle position of the chemical solution nozzle 31 may be provided in the processing unit 1B. For example, a rotary encoder for measuring the rotational position of the motor of the nozzle displacement drive unit 36 ​​may be provided. The control unit 9 may calculate the nozzle position of the chemical solution nozzle 31 based on the measurement result of the rotary encoder.

[0141] The adhesion detection unit 6 determines that the chemical solution is colliding with the brush holding unit 5 when the flow rate is equal to or greater than a flow rate threshold and the brush 4 is located within a predetermined range Rb corresponding to the nozzle position of the chemical solution nozzle 31. Correspondence relationship data showing the correspondence between the nozzle position and the predetermined range Rb is set in advance, for example, by experiment or simulation. This correspondence relationship data can be set in, for example, a non-volatile storage unit 97 (see Figure 13). The storage unit 97 may be a hard disk or various types of memory. The correspondence between the nozzle position and the predetermined range Rb may be defined discretely in table format or continuously by a function expression or the like. As shown in Figure 13, in the third embodiment, the adhesion detection unit 6 includes a flow meter 35a, a brush position acquisition unit, a nozzle position acquisition unit, and a storage unit 97.

[0142] Figure 14 is a flowchart showing an example of the operation of the processing unit 1B according to the third embodiment for brush cleaning. In the example in Figure 14, the processing unit 1B further executes step S130 in parallel with scrubber cleaning. In the example in Figure 14, in the next step S130 after step S13, the nozzle position acquisition unit (here, the control unit 9, specifically the nozzle displacement control unit 96) acquires the nozzle position of the chemical solution nozzle 31 (nozzle position acquisition step). Note that the execution order of steps S12, S13 and S130 can be changed as appropriate.

[0143] Next, the adhesion determination unit 93 determines whether or not the chemical solution has adhered to the brush holding unit 5 based on the flow rate of the chemical solution, the brush position of the brush 4, and the nozzle position of the chemical solution nozzle 31 (step S14: determination step). As a specific example, the adhesion determination unit 93 determines a predetermined range Rb(t) corresponding to the nozzle position based on the nozzle position acquired by the nozzle position acquisition unit and the correspondence relationship data read from the storage unit 97. The adhesion determination unit 93 then determines that the chemical solution has adhered to the brush holding unit 5 when the flow rate is equal to or greater than a predetermined flow rate threshold and the brush 4 is located within the predetermined range Rb(t) corresponding to the nozzle position. Conversely, the adhesion determination unit 93 determines that the chemical solution has not adhered to the brush holding unit 5 even if the flow rate is equal to or greater than the flow rate threshold, if the brush 4 is outside the predetermined range Rb(t). Also, the adhesion determination unit 93 determines that the chemical solution has not adhered to the brush holding unit 5 regardless of the position of the brush 4 when the flow rate is less than the flow rate threshold.

[0144] As described above, in the third embodiment, the adhesion detection unit 6 detects the adhesion of the chemical solution to the brush holding unit 5 based on the flow rate of the chemical solution, the brush position of the brush holding unit 5, and the nozzle position of the chemical solution nozzle 31. Therefore, the adhesion detection unit 6 can detect the adhesion of the chemical solution to the brush holding unit 5 with higher accuracy.

[0145] <Fourth Embodiment> Figure 15 is a schematic longitudinal cross-sectional view showing an example of the configuration of processing unit 1C according to the fourth embodiment. Processing unit 1C differs from processing unit 1 in that it has a camera 61. The camera 61 captures an image of the brush holding unit 5 to generate image data IM and outputs the image data IM to the control unit 9. The camera 61 may also capture an image of the brush holding unit 5 in response to an imaging instruction from the control unit 9.

[0146] The camera 61 includes a solid-state image sensor, such as a CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor), and an optical system such as a lens. In the example shown in Figure 15, the camera 61 is positioned vertically above the substrate W held by the substrate holding part 2 and radially outward from the substrate W. The imaging direction of the camera 61 is set diagonally downward and toward the rotation axis Q1. Here, the camera 61 is capable of imaging the brush holding part 5 over the entire range of movement R of the brush 4 during scrubber cleaning. In other words, the camera 61 is positioned so that the brush holding part 5 over the entire range within the movement range R is included in the imaging range. To put it another way, the camera 61 is positioned to image the brush holding part 5 when the brush 4 is in the processing position.

[0147] Figure 16 schematically shows an example of image data IM generated by camera 61. Since camera 61 takes images at an oblique angle, the substrate W is schematically shown as an ellipse in the example in Figure 16. The brush 4 and brush holder 5 are also schematically shown. In reality, various components such as the arm 400, chemical nozzle 31, and guard (not shown) may be included in the image data IM. In the example in Figure 16, the image data IM schematically shows the chemical liquid discharged from the chemical nozzle 31 in the sandy area. Here, the chemical liquid is colliding with the brush holder 5. In other words, camera 61 may be positioned in the brush holder 5 at a location where the collision point of the chemical liquid is included in the image data IM.

[0148] In the fourth embodiment, the adhesion detection unit 6 detects the adhesion of the chemical solution to the brush holding unit 5 based on image data IM generated by the camera 61.

[0149] Figure 17 is a schematic block diagram showing an example of the electrical configuration of the processing unit 1C according to the fourth embodiment. In the example in Figure 17, the adhesion detection unit 6 includes a camera 61, an adhesion determination unit 93, and a storage unit 97. In the example in Figure 17, image data IM from the camera 61 is input to the control unit 9. The adhesion determination unit 93 of the control unit 9 determines whether or not the chemical solution is adhering to the brush holding unit 5 based on the image data IM.

[0150] As a specific example, the adhesion determination unit 93 compares the image data IM with the reference image data RI. The reference image data RI is, for example, an image that includes at least a portion of the brush holding part 5 that does not have any chemical solution attached to it. In Figure 16, the reference image data RI is schematically shown by a dashed line. In the example in Figure 16, the vertical size of the reference image data RI is smaller than the vertical size of the image data IM, for example, less than a fraction of the vertical size of the image data IM. The horizontal size of the reference image data RI is smaller than the horizontal size of the image data IM, for example, less than a fraction of the horizontal size of the image data IM. In the example in Figure 16, the reference image data RI includes the entire horizontal and vertical portions of the brush holding part 5. In other words, in the example in Figure 16, the horizontal size of the reference image data RI is slightly larger than the horizontal size of the brush holding part 5, and the vertical size of the reference image data RI is slightly larger than the vertical size of the brush holding part 5.

[0151] Such reference image data RI is acquired by a prior registration process, for example, as follows. First, with the substrate holding unit 2 holding the substrate W, the brush movement drive unit 410 moves the brush 4 to, for example, the central position Pb1. Then, the camera 61 captures an image area and generates image data IM. Based on user input to a user interface (not shown), the control unit 9 extracts a portion of the image data IM, including the brush holding unit 5, as reference image data RI. Then, the control unit 9 stores the reference image data RI in the storage unit 97. As described above, a prior registration process is performed.

[0152] The adhesion determination unit 93 of the control unit 9 identifies the region IMa in the image data IM that has the highest similarity to the reference image data RI through a matching process (e.g., template matching) between the image data IM and the reference image data RI. If no chemical solution adheres to the brush holding part 5 in the image data IM, the similarity between region IMa and the reference image data RI is relatively high. On the other hand, if chemical solution adheres to the brush holding part 5 in the image data IM, the similarity between region IMa and the reference image data RI is relatively low. Conversely, when the similarity is high, it can be assumed that no chemical solution adheres to the brush holding part 5, and when the similarity is low, it can be assumed that chemical solution adheres to the brush holding part 5.

[0153] Therefore, the adhesion determination unit 93 determines whether the similarity between region IMa and reference image data RI is equal to or greater than a predetermined similarity threshold. The similarity threshold is a threshold for determining whether or not the chemical solution is present, and is set in advance, for example, by experiment or simulation. The adhesion determination unit 93 determines that no chemical solution is present on the brush holding unit 5 when the similarity is equal to or greater than the similarity threshold, and determines that chemical solution is present on the brush holding unit 5 when the similarity is less than the similarity threshold.

[0154] Figure 18 is a flowchart illustrating an example of the operation of the processing unit 1C related to brush cleaning. In the example in Figure 18, when scrubber cleaning (step S2) is started (step S21), the processing unit 1C executes steps S22 to S24, which are described later. In other words, the processing unit 1C executes steps S22 to S24 in parallel with scrubber cleaning (step S2). First, the camera 61 captures the imaging area and generates image data IM (step S22: imaging process). Then, the camera 61 outputs the image data IM to the control unit 9.

[0155] Next, the adhesion determination unit 93 determines whether or not the chemical solution is adhering to the brush holding unit 5 based on the image data IM (step S23: determination step). As a specific example, as described above, the adhesion determination unit 93 finds the region IMa with the highest similarity by matching the image data IM with the reference image data RI. Since the brush 4 moves within the movement range R, the position of the brush 4 within the image data IM also moves, but the adhesion determination unit 93 can appropriately find the region IMa through the matching process. The similarity is not particularly limited, but may be a known similarity such as the sum of squared differences of pixel values, the sum of absolute differences of pixel values, normalized cross-correlation, and zero-mean normalized cross-correlation. The adhesion determination unit 93 then determines whether or not the similarity is equal to or greater than the similarity threshold.

[0156] When the adhesion detection unit 93 determines that chemical solution is adhering to the brush holding unit 5, the control unit 9 determines that cleaning of the brush holding unit 5 is necessary, similar to step S15 (step S24).

[0157] Next, the control unit 9 determines whether the scrubber cleaning is complete or not, similar to step S16 (step S25). If the control unit 9 determines that the scrubber cleaning is not yet complete, the processing unit 1C executes step S22 again.

[0158] If the adhesion determination unit 93 determines in step S23 that no chemical solution is adhering to the brush holding unit 5, the control unit 9 proceeds to step S25 without performing step S24.

[0159] As described above, the series of processes from step S22 to step S24 are repeatedly executed until the scrubber cleaning is completed. Therefore, if the adhesion detection unit 93 detects the adhesion of the chemical solution to the brush holding unit 5 even once during scrubber cleaning, the control unit 9 determines that cleaning of the brush holding unit 5 is necessary.

[0160] Once the scrubber cleaning is complete, the control unit 9 determines, in the same manner as in step S17, whether or not cleaning of the brush holder 5 is necessary (step S26). If cleaning of the brush holder 5 is necessary, the control unit 9 performs the first brush cleaning in the same manner as in step S18 (step S27: first brush cleaning step). If cleaning of the brush holder 5 is not necessary, the control unit 9 performs the second brush cleaning in the same manner as in step S19 (step S28: second brush cleaning step).

[0161] As described above, in the fourth embodiment, the adhesion detection unit 6 detects the adhesion of the chemical solution to the brush holding unit 5 based on the image data IM from the camera 61. Therefore, the adhesion detection unit 6 can detect the adhesion of the chemical solution to the brush holding unit 5 with higher accuracy.

[0162] Furthermore, in the example described above, the adhesion detection unit 6 detects the adhesion of the chemical solution to the brush holding unit 5 based on a comparison between the image data IM from the camera 61 and the reference image data RI. Therefore, the adhesion detection unit 6 can detect the adhesion of the chemical solution with a simpler process.

[0163] Furthermore, in the example described above, the camera 61 is positioned to image the brush holding portion 5 when the brush 4 is in contact with the main surface of the substrate W. Therefore, the adhesion detection unit 6 can detect the adhesion of the chemical solution to the brush holding portion 5 during scrubber cleaning.

[0164] <Location of camera 61> <Standby Pod> Figure 19 is a diagram illustrating another first example of the position of camera 61. In the example of Figure 19, camera 61 is positioned to image the brush holder 5 when it is located in the standby pod 7. In the example of Figure 19, the side wall of the standby pod 7 is transparent, and camera 61 is positioned facing the side wall of the standby pod 7. The imaging direction of camera 61 may be set, for example, horizontally.

[0165] Camera 61 images the brush holder 5 through the side wall of the standby pod 7 and generates image data IM. Camera 61 outputs the image data IM to the control unit 9. The image data IM includes the side view of the brush holder 5. As a more specific example, the image data IM may include the entire lateral and vertical views of the brush holder 5. Since the brush 4 does not need to move in the standby pod 7 for the purpose of determining the adhesion of the chemical solution, the size of the brush holder 5 in the image data IM may be set to be large. In other words, the installation position of camera 61 may be determined so that the size of the brush holder 5 in the image data IM is large.

[0166] Camera 61 captures an image of the brush holder 5 and generates image data IM when the cleaning fluid supply unit 8 is not supplying cleaning fluid to the brush holder 5 and brush 4. The adhesion determination unit 93 of the control unit 9 determines, based on the image data IM, whether or not the cleaning fluid is adhering to the brush holder 5. As a specific example, the adhesion determination unit 93 may compare the image data IM with reference image data RI. In this case, the reference image data RI includes, for example, the brush holder 5 stored in the standby pod 7 when no cleaning fluid is adhering to the brush holder 5. This reference image data RI is also acquired in advance and stored in the storage unit 97. The size of the brush holder 5 in the reference image data RI may be the same as the size of the brush holder 5 in the image data IM.

[0167] The adhesion determination unit 93 calculates the similarity between the image data IM and the reference image data RI. The adhesion determination unit 93 determines that no chemical solution is attached to the brush holding unit 5 when the similarity is equal to or greater than the similarity threshold, and determines that chemical solution is attached to the brush holding unit 5 when the similarity is less than the similarity threshold. In this case, matching processing is not required.

[0168] As described above, the adhesion detection unit 6 detects the adhesion of the chemical solution to the brush holding unit 5 located in the standby pod 7. Since no liquid is supplied to the brush holding unit 5 in the standby pod 7, the image data IM contains almost no flowing liquid. Therefore, the adhesion detection unit 6 can detect the adhesion of the chemical solution with higher accuracy.

[0169] Furthermore, the brush drive unit 401 may rotate the brush 4 and the brush holder 5 at least once around the rotation axis Q2. The camera 61 may sequentially image the brush holder 5 at multiple timings while the brush 4 and the brush holder 5 are rotating, thereby generating multiple image data IMs. In other words, the camera 61 may image the brush holder 5 at each of the multiple rotation positions. As a result, each of the multiple image data IMs will include different parts of the side surface of the brush holder 5. The camera 61 should image the brush holder 5 at time intervals such that the entire circumference of the side surface of the brush holder 5 is included in the total of the multiple image data IMs.

[0170] The adhesion determination unit 93 compares each of the multiple image data IMs with the reference image data RI. The adhesion determination unit 93 determines that the chemical solution is attached to the brush holding unit 5 when the similarity between any one of the image data IMs and the reference image data RI is less than a predetermined similarity threshold.

[0171] According to this, the adhesion detection unit 6 can check the entire circumferential surface of the brush holding unit 5, so it can detect the adhesion of the chemical solution with higher accuracy. Specifically, even if the chemical solution adheres to only a part of the side surface of the brush holding unit 5, the adhesion detection unit 6 can appropriately detect the adhesion of the chemical solution.

[0172] <On the move> Figure 20 illustrates another second example of the camera 61's position. In the example of Figure 20, the camera 61 is positioned to image the brush holder 5 when the brush 4 is located between the processing position and the standby pod 7. In other words, the camera 61 is positioned to image the brush holder 5 in at least a portion of the movement path of the brush 4 between the position on the substrate W held by the substrate holder 2 and the standby pod 7. The imaging direction of the camera 61 can be set, for example, horizontally.

[0173] Camera 61 images the brush holder 5 located along the movement path. For example, camera 61 may image the brush holder 5 and generate image data IM while the brush 4 is moving horizontally toward the standby pod 7. Camera 61 outputs the image data IM to the control unit 9. The image data IM includes the side view of the moving brush holder 5, and may include, for example, the entire lateral and vertical views of the brush holder 5.

[0174] The adhesion determination unit 93 of the control unit 9 determines whether or not the chemical solution is attached to the brush holder 5 based on the image data IM. As a specific example, the adhesion determination unit 93 may compare the image data IM with reference image data RI. In this case, the reference image data RI includes, for example, the brush holder 5 in motion when no chemical solution is attached to it. This reference image data RI is also acquired in advance and stored in the storage unit 97. Then, as described above, the adhesion determination unit 93 performs a matching process between the image data IM and the reference image data RI to identify the region with the highest similarity. When the similarity is equal to or greater than the similarity threshold, the adhesion determination unit 93 determines that no chemical solution is attached to the brush holder 5, and when the similarity is less than the similarity threshold, it determines that the chemical solution is attached to the brush holder 5.

[0175] As described above, the adhesion detection unit 6 can detect the adhesion of the chemical solution to the brush holding unit 5 while the brush 4 is moving between the standby pod 7 and the processing position. Since no liquid is supplied while the brush 4 is moving, the image data IM contains almost no flowing liquid. Therefore, the adhesion detection unit 6 can detect the adhesion of the chemical solution with higher accuracy.

[0176] The brush drive unit 401 may rotate the brush 4 at least once around the rotation axis Q2 while the brush 4 is moving, and the camera 61 may image the brush holder 5 at each of the multiple rotation positions to generate multiple image data IMs. As a result, each of the multiple image data IMs includes different parts of the side surface of the brush holder 5. The camera 61 may image the brush holder 5 at time intervals such that the entire circumference of the side surface of the brush holder 5 is included in the total of the multiple image data IMs.

[0177] The adhesion determination unit 93 then compares each of the multiple image data IMs with the reference image data RI. The adhesion determination unit 93 determines that chemical solution is attached to the brush holding unit 5 when the highest similarity obtained from the matching process between any one of the image data IMs and the reference image data RI is less than the similarity threshold. As a result, the adhesion detection unit 6 can check the entire circumferential surface of the brush holding unit 5, and can detect the attachment of chemical solution with higher accuracy.

[0178] <Fifth Embodiment> Figure 21 is a schematic diagram showing an example of the configuration of a processing unit 1D according to the fifth embodiment. The processing unit 1D is provided with two standby pods 7. Hereinafter, the two standby pods 7 will be referred to as standby pod 7A and standby pod 7B, respectively. In a plan view, standby pod 7A is provided on the opposite side of the substrate holding section 2 from standby pod 7B. In other words, the substrate holding section 2 is provided between standby pod 7A and standby pod 7B in a plan view.

[0179] Furthermore, the processing unit 1D is provided with two brushes 4, two brush holders 5, two arms 400, and two brush movement drive units 410. Hereinafter, the two brushes 4 will be referred to as brush 4A and brush 4B, the two brush holders 5 as brush holder 5A and brush holder 5B, the two arms 400 as arm 400A and arm 400B, and the two brush movement drive units 410 as brush movement drive unit 410A and brush movement drive unit 410B.

[0180] The brush holder 5A holds the brush 4A, and the brush holder 5B holds the brush 4B. The arm 400A is connected to the brush holder 5A via a shaft, and the arm 400B is connected to the brush holder 5B via a shaft (not shown). Inside the arm 400A is a brush drive unit 401 (not shown) that drives the brush 4A, and inside the arm 400B is a brush drive unit 401 (not shown) that drives the brush 4B.

[0181] The brush movement drive unit 410A moves the brush 4A, brush holder 5A, and arm 400A together, and the brush movement drive unit 410B moves the brush 4B, brush holder 5B, and arm 400B together. The brush movement drive unit 410A moves the brush 4A between the standby pod 7A and a position on the main surface of the substrate W, and the brush movement drive unit 410B moves the brush 4B between the standby pod 7B and a position on the main surface of the substrate W. In addition, the brush movement drive unit 410A moves the brush 4A along the main surface of the substrate W while the brush 4A is in contact with the main surface of the substrate W, and the brush movement drive unit 410B moves the brush 4B along the main surface of the substrate W while the brush 4B is in contact with the main surface of the substrate W.

[0182] The processing unit 1D is equipped with two cleaning fluid supply units 8. Hereinafter, the two cleaning fluid supply units 8 will be referred to as cleaning fluid supply unit 8A and cleaning fluid supply unit 8B, respectively. Cleaning fluid supply unit 8A supplies cleaning fluid to standby pod 7A, and cleaning fluid supply unit 8B supplies cleaning fluid to standby pod 7B.

[0183] Such a processing unit 1D can clean the main surface of the substrate W using brush 4A, and can also clean the main surface of the substrate W using brush 4B.

[0184] The adhesion detection unit 6 can detect the adhesion of the chemical solution to the brush holding unit 5A. For example, the adhesion detection unit 6 may detect the adhesion of the chemical solution based on the flow rate of the chemical solution, as in the first embodiment, or it may detect the adhesion of the chemical solution based on the flow rate of the chemical solution and the brush position of the brush 4A. Alternatively, the adhesion detection unit 6 may detect the adhesion of the chemical solution based on the flow rate of the chemical solution, the brush position of the brush 4A, and the nozzle position of the chemical solution nozzle 31, as in the third embodiment. Alternatively, the adhesion detection unit 6 may detect the adhesion of the chemical solution based on the image data IM of the camera 61, as in the fourth embodiment. When the adhesion detection unit 6 detects the adhesion of the chemical solution to the brush holding unit 5A, the control unit 9 performs a first brush cleaning in the standby pod 7A after scrubber cleaning. This cleans the brush holding unit 5A and the brush 4A. When the adhesion detection unit 6 does not detect the adhesion of the chemical solution to the brush holding unit 5A, the control unit 9 performs a second brush cleaning in the standby pod 7A after scrubber cleaning. This cleans the brush 4A.

[0185] The adhesion detection unit 6 can also detect the adhesion of chemical solution to the brush holder 5B. The method for detecting the adhesion of chemical solution to the brush holder 5B by the adhesion detection unit 6 is the same as the method for detecting the adhesion of chemical solution to the brush holder 5A. When the adhesion detection unit 6 detects the adhesion of chemical solution to the brush holder 5B, the control unit 9 performs a first brush cleaning in the standby pod 7B after scrubbing. This cleans the brush holder 5B and the brush 4B. If the adhesion detection unit 6 does not detect the adhesion of chemical solution to the brush holder 5B, the control unit 9 performs a second brush cleaning in the standby pod 7B after scrubbing. This cleans the brush 4B.

[0186] As described above, the substrate processing apparatus and substrate processing method have been explained in detail, but the above explanation is illustrative in all respects, and this disclosure is not limited thereto. Furthermore, the various modifications described above can be applied in combination as long as they do not contradict each other. And it is understood that many modifications not illustrated can be conceivable without falling outside the scope of this disclosure. [Explanation of symbols]

[0187] 2 Board holding part 31 Chemical solution nozzle 35a flow meter 4, 4A, 4B brushes 401 Brush drive unit 410 Brush movement drive unit 5, 5A, 5B Brush holding section 6. Adhesion detection unit 61 Camera 7 Standby Pods 8,8A,8B Cleaning fluid supply unit 81a First washing nozzle 81b Second cleaning nozzle 8a,8b outlet 9. Control Unit 92 Brush position acquisition unit (brush control unit) 96 Nozzle position acquisition unit (nozzle displacement control unit) 97 Memory section IM image data RI reference image data T brush cleaning time T1 1st hour T2 2nd hour VL1,VL2 straight line W board

Claims

1. A substrate holding unit that holds the substrate and rotates the substrate around a predetermined axis of rotation, A liquid chemical nozzle that discharges the liquid chemical toward the main surface of the substrate held by the substrate holding portion, A brush used for cleaning the main surface of the substrate held by the substrate holding portion, A brush holding portion is provided above the aforementioned brush and holds the aforementioned brush, Standby pod and, A brush movement drive unit moves the brush holding unit and a set of brushes between a processing position in which the brush contacts the main surface of the substrate and the standby pod, A contact detection unit for detecting the adhesion of the chemical solution to the brush holding unit, A cleaning fluid supply unit having a discharge port for supplying cleaning fluid to the standby pod, Control unit and Equipped with, A substrate processing apparatus comprising: a control unit which determines that cleaning of the brush holder is necessary when the adhesion detection unit detects the adhesion of the chemical solution to the brush holder, and controls the cleaning solution supply unit to clean the brush holder with the cleaning solution when the brush movement drive unit moves a set of the brush holder and the brush to the standby pod.

2. A substrate processing apparatus according to claim 1, The substrate processing apparatus includes a flow meter that measures the flow rate of the chemical solution discharged from the chemical solution nozzle, and detects the adhesion of the chemical solution to the brush holding part based on the flow rate of the chemical solution measured by the flow meter.

3. A substrate processing apparatus according to claim 2, The substrate processing apparatus further includes a brush position acquisition unit that acquires the brush position of the brush, and detects the adhesion of the chemical solution to the brush holding unit based on the flow rate of the chemical solution measured by the flow meter and the brush position of the brush acquired by the brush position acquisition unit.

4. A substrate processing apparatus according to claim 3, The system further comprises a nozzle displacement drive unit that displaces the chemical solution nozzle to move the point of contact of the chemical solution on the main surface of the substrate, The adhesion detection unit is The system further includes a nozzle position acquisition unit that acquires the nozzle position of the aforementioned chemical solution nozzle, A substrate processing apparatus that detects the adhesion of the chemical solution to the brush holding part based on the flow rate of the chemical solution measured by the flow meter, the brush position of the brush acquired by the brush position acquisition unit, and the nozzle position of the chemical solution nozzle acquired by the nozzle position acquisition unit.

5. A substrate processing apparatus according to any one of claims 1 to 4, The substrate processing apparatus includes a camera that captures images of the brush holding portion and generates image data, and detects the adhesion of the chemical solution to the brush holding portion based on the image data.

6. A substrate processing apparatus according to claim 5, The system includes a storage unit that stores reference image data including the brush holding portion to which the aforementioned chemical solution is not attached, The substrate processing apparatus includes an adhesion detection unit that detects the adhesion of the chemical solution to the brush holding unit based on a comparison between the image data and the reference image data.

7. A substrate processing apparatus according to claim 5, The substrate processing apparatus is provided with a camera positioned to capture an image of the brush holding portion when the brush is in the processing position.

8. A substrate processing apparatus according to claim 5, The substrate processing apparatus is provided with a camera positioned to capture an image of the brush holding portion when the brush is located in the standby pod.

9. A substrate processing apparatus according to claim 5, The substrate processing apparatus is provided with a camera positioned to image the brush holding portion when the brush is located between the standby pod and the processing position.

10. A substrate processing apparatus according to claim 5, The brush drive unit further comprises a unit that rotates the brush and the brush holder integrally. The camera is a substrate processing apparatus that generates a plurality of image data by sequentially imaging the brush holding part while the brush drive unit rotates the brush and the brush holding part.

11. A substrate processing apparatus according to any one of claims 1 to 4, The control unit, while the chemical solution is being discharged from the chemical solution nozzle, moves the brush and the brush holding unit together on the main surface of the substrate using the brush moving drive unit, thereby performing scrubbing of the main surface of the substrate. A substrate processing apparatus wherein, in a plan view, a virtual straight line along the trajectory of the chemical solution from the discharge port of the chemical solution nozzle to the main surface of the substrate intersects with a virtual straight line along the trajectory of the movement of the brush in the scrubber cleaning.

12. A substrate processing apparatus according to any one of claims 1 to 4, The aforementioned cleaning fluid supply unit is A first cleaning nozzle that discharges the cleaning liquid toward the brush holding portion, A second cleaning nozzle that discharges the cleaning solution toward the brush, A substrate processing apparatus, including

13. A substrate processing apparatus according to claim 12, The substrate processing apparatus comprises a cleaning fluid supply unit that discharges the cleaning fluid from the first cleaning nozzle only for a portion of the brush cleaning time (a first hour), and discharges the cleaning fluid from the second cleaning nozzle for at least a second hour that is after the first hour.

14. A substrate processing apparatus according to claim 13, The substrate processing apparatus wherein the cleaning liquid supply unit does not discharge the cleaning liquid from the second cleaning nozzle for at least a portion of the first time.

15. A substrate processing apparatus according to any one of claims 1 to 4, The control unit performs the process of raising and lowering the brush in the standby pod using the brush movement drive unit to bring the brush into contact with the cleaning liquid, and the process of bringing the cleaning liquid into contact with the brush holding unit, in a substrate processing apparatus.

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