JP2020035961A - Substrate processing method and substrate processing apparatus - Google Patents

Abstract

To provide a technique for appropriately determining a timing of starting a subsequent second process after a first process which is a liquid process.SOLUTION: After supply of a first processing liquid is stopped, an upper surface of a substrate W is photographed by a camera 70. In a determination area DR of a photographed image 82 acquired by the camera 70, an interference fringe ST is detected by detecting an extreme point of luminance (light intensity) in a radial direction. When the interference fringe ST to be detected is detected, a timing determination unit 92 determines a timing to start the second process.SELECTED DRAWING: Figure 8

Description

  The present invention relates to a technology for processing a substrate, and more particularly, to a technology for processing a substrate with a processing liquid. Examples of the substrate to be processed include a semiconductor substrate, a flat panel display (FPD) substrate such as a liquid crystal display device and an organic EL (Electroluminescence) display device, a substrate for an optical disk, a substrate for a magnetic disk, a substrate for a magneto-optical disk, Examples include a photomask substrate, a ceramic substrate, a solar cell substrate, a printed circuit board, and the like.

  In semiconductor manufacturing, there is a case where first processing for treating the surface of a semiconductor substrate with a predetermined liquid is performed first, and then another second processing is performed for the semiconductor substrate. For example, Patent Literature 1 describes that a semiconductor substrate having a fine pattern on its surface is treated with a hydrophobizing agent to suppress collapse of the fine pattern. More specifically, after the semiconductor substrate is first treated with liquid PGMEA (propylene glycol monomethyl ether acetate), the semiconductor substrate is treated with a hydrophobizing agent.

  Patent Document 2 discloses a technique for suppressing collapse of a resist pattern when a substrate is dried by high-speed rotation. Specifically, the substrate on which the resist pattern is formed is first subjected to a liquid process of supplying a rinsing liquid as a first process, and then a second process is a drying process in which the substrate is rotated at a high speed and dried. Done. Patent Document 2 discloses that after the supply of the rinsing liquid is completed, the rotation speed of the substrate is controlled in accordance with the extension of the drying area on the main surface of the substrate from the center of the substrate toward the outer periphery. Is described by measuring a change in interference fringes.

JP 2010-114414 A JP 2004-335542 A

  In general, the thickness of the liquid film of the first processing liquid supplied to the substrate in the first processing may affect the subsequent second processing. For example, in the case of Patent Literature 1, PGMEA is supplied to the substrate in the first process, and after the supply is stopped, the hydrophobizing agent, which is the second process, is supplied to the substrate. At this time, if the PGMEA liquid film on the substrate is excessively thick, the efficiency of substitution with the hydrophobizing agent decreases. However, Patent Document 1 does not disclose any technique for supplying a hydrophobizing agent at an optimal timing.

  Further, Patent Literature 2 only describes that control for starting the drying process of the second process is performed by measuring a change in interference fringes, and does not disclose any technology for detecting interference fringes. For this reason, it is difficult to appropriately determine the timing for starting the drying process based on Reference 2.

  Therefore, an object of the present invention is to provide a technique for appropriately determining the timing of starting the subsequent second processing after the first processing which is a liquid processing.

  In order to solve the above problems, a first aspect is a substrate processing method for processing an upper surface of a substrate rotating in a horizontal posture with a processing liquid, comprising: (a) holding the substrate in a horizontal posture; Rotating the substrate held in the horizontal posture in the step (a) around a vertical rotation axis; and (c) supplying the first processing liquid to the upper surface of the substrate rotated in the step (b). And (d) stopping the supply of the first processing liquid after the step (c); and (e) the first processing liquid remaining on the upper surface of the substrate after the step (d). (F) a step of photographing the upper surface of the substrate with a camera in the step (e); and (g) a determination area set in the photographed image acquired in the step (f). Within, the light intensity in the radial direction orthogonal to the rotation axis Determining a timing at which the second processing is performed on the substrate according to an extreme point at which the maximum or minimum is obtained; and (h) determining a timing with respect to the substrate according to the timing determined at the step (g). Performing the second process.

  A second aspect is the substrate processing method according to the first aspect, wherein in the step (h), the second processing is started while the film of the first processing liquid remains on the entire upper surface of the substrate. Is done.

  A third aspect is the substrate processing method according to the first aspect or the second aspect, wherein the determination region is set in the upper surface of the substrate.

  A fourth aspect is the substrate processing method according to the third aspect, wherein in the step (g), (g1) one extreme point is detected in the determination area, and then the next extreme point is detected. And determining the timing according to the time up to.

  A fifth aspect is the substrate processing method according to the fourth aspect, wherein the step (g) comprises: (g2) detecting a first extreme point and then detecting a second extreme point in the determination area. Determining the timing based on a first time until the second extreme point is detected and a second time from when the second extreme point is detected to when a third extreme point is detected.

  A sixth aspect is the substrate processing method according to any one of the first to third aspects, wherein the step (g) comprises: (g3) the first extreme point detected in the determination area and the second extreme point. Determining the timing based on a first distance between a first extreme point and a second extreme point radially inward.

  A seventh aspect is the substrate processing method according to the sixth aspect, wherein the determination area includes a first determination area and a second determination area radially inward from the first determination area. g) determining the timing based on (g4) detecting the first extreme point in the first determination area and detecting the second extreme point in the second determination area; Process.

  An eighth aspect is the substrate processing method according to the seventh aspect, wherein (i) changing a radial position of the second determination area with respect to the first determination area in the radial direction before the step (g). Further comprising the step of:

  A ninth aspect is the substrate processing method according to any one of the sixth to eighth aspects, wherein the step (g) comprises: (g5) the first distance and the second pole in the determination area. Determining the timing based on a second distance between the value point and a third extreme point radially inward from the second extreme point.

  A tenth aspect is the substrate processing method according to any one of the first to ninth aspects, wherein the step (g) comprises: (g6) detecting a last one of a plurality of extreme points in the determination area. Determining the timing by detecting any of the three extreme points, counting from a possible final extreme point.

  An eleventh aspect is the substrate processing method according to any one of the first to tenth aspects, wherein the camera is an infrared camera.

  A twelfth aspect is the substrate processing method according to the eleventh aspect, wherein the step (f) includes a step (f1) of irradiating the upper surface of the substrate with infrared rays.

  A thirteenth aspect is the substrate processing method according to any one of the first to twelfth aspects, wherein the second processing supplies a second processing liquid different from the first processing liquid to an upper surface of the substrate. Processing.

  A fourteenth aspect is the substrate processing method according to any one of the first to twelfth aspects, wherein the second processing is performed by setting a rotation speed of the substrate higher than that in the step (e). This is a process for removing the first processing liquid remaining on the upper surface of the substrate.

  A fifteenth aspect is a substrate processing apparatus that performs processing liquid processing on an upper surface of a substrate that rotates in a horizontal posture, and a substrate holding unit that holds the substrate in a horizontal posture, and a target substrate that is a substrate held by the substrate holding unit. A rotating unit that rotates the substrate about a vertical rotation axis, a first processing liquid supply unit that supplies a first processing liquid to the upper surface of the target substrate, a camera that captures an image of the upper surface of the target substrate, and a camera that captures the image. In the determination region set in the photographed image to be taken, the target is adjusted in accordance with the movement of the extreme point where the light intensity in the radial direction orthogonal to the rotation axis becomes the maximum value or the minimum value toward the radial outside. A timing determining unit that determines a timing of performing the second processing on the substrate; and a second processing performing unit that performs the second processing on the target substrate in accordance with the timing determined by the timing determining unit. Obtain.

  A sixteenth aspect is the substrate processing apparatus according to the fifteenth aspect, wherein the determination region is set in the upper surface of the target substrate.

  A seventeenth aspect is the substrate processing apparatus according to the fifteenth aspect or the sixteenth aspect, wherein the timing determination unit is configured to extract a plurality of types of feature vectors from the captured image, and the plurality of types of feature vectors. And an image determination unit that determines whether or not the captured image is an image serving as a guide for determining the timing based on

  According to the substrate processing method of the first aspect, when the supply of the first processing liquid is stopped, the first processing liquid is shaken off by the rotation of the substrate, so that the thickness of the liquid film gradually decreases. At this time, interference fringes that move radially outward occur according to the thickness of the liquid film. The interference fringes correspond to extreme points where the light intensity has an extreme value. Therefore, by determining the timing of performing the second processing based on the extreme point of the light intensity, the second processing can be started at a timing at which the liquid film of the first processing liquid has an optimum thickness.

  According to the substrate processing method of the second aspect, the second processing is started with the first processing liquid remaining on the entire upper surface of the substrate. For this reason, it can suppress that a drying of a board | substrate advances locally.

  According to the substrate processing method of the third aspect, a region excluding the upper surface of the substrate in the captured image is set as the determination region. Thereby, the detection accuracy of the extreme point corresponding to the interference fringe generated on the upper surface of the substrate can be improved.

  According to the substrate processing method of the fourth aspect, the degree of progress of thinning can be detected from the difference between the times when two extreme points pass through the determination area. Therefore, the start timing of the second process is determined.

  According to the substrate processing method of the fifth aspect, by calculating the first time and the second time, it is possible to determine whether or not an interference fringe to be detected has appeared.

  According to the substrate processing method of the sixth aspect, it is possible to determine whether or not an interference fringe to be detected has appeared by calculating the first distance.

  According to the substrate processing method of the seventh aspect, the first and second determination areas that are separated from each other by an appropriate distance in the radial direction are set, and interference fringes are detected in these determination areas. Can be determined whether or not has appeared.

  According to the substrate processing method of the eighth aspect, the relative position of the second determination region with respect to the first determination region can be changed in the radial direction. Thereby, the first extreme value point and the second extreme value point serving as indices for determining the timing of the second processing can be simultaneously detected in, for example, each of the first determination region and the second determination region.

  According to the substrate processing method of the ninth aspect, by acquiring the first distance and the second distance, it is possible to determine whether or not an interference fringe to be detected has appeared.

  According to the substrate processing method of the tenth aspect, the timing at which the second processing is performed can be determined at a stage before the thickness of the liquid film of the first processing liquid becomes so thin that interference fringes cannot be detected.

  According to the substrate processing method of the eleventh aspect, by detecting infrared rays, it is possible to appropriately detect the light intensity corresponding to the interference fringes.

  According to the substrate processing method of the twelfth aspect, by irradiating infrared rays, the light intensity corresponding to the interference fringes can be appropriately detected.

  According to the substrate processing method of the thirteenth aspect, the second processing liquid can be supplied when the first processing liquid has a target thickness. Therefore, the replacement of the first processing solution with the second processing solution can be performed quickly, and the amount of the second processing solution used can be reduced.

  According to the substrate processing method of the fourteenth aspect, the rotation speed of the substrate is increased when the first processing liquid has a target thickness. Non-uniform processing of the substrate with a large amount of the first processing liquid can be suppressed.

  According to the substrate processing apparatus of the fifteenth aspect, when the supply of the first processing liquid is stopped, the first processing liquid is shaken off by the rotation of the substrate, so that the thickness of the liquid film gradually decreases. At this time, interference fringes that move radially outward occur according to the thickness of the liquid film. The interference fringes correspond to extreme points where the light intensity has an extreme value. Therefore, by determining the timing of performing the second processing based on the extreme point of the light intensity, the second processing can be started at a timing at which the liquid film of the first processing liquid has an optimum thickness.

  According to the substrate processing apparatus of the sixteenth aspect, interference fringes appearing on the substrate can be detected.

FIG. 1 is a diagram illustrating an overall configuration of a substrate processing apparatus 100 according to a first embodiment. It is a schematic plan view of cleaning processing unit 1 of a 1st embodiment. It is an outline longitudinal section of cleaning processing unit 1 of a 1st embodiment. FIG. 3 is a diagram illustrating a positional relationship between a camera 70 and a nozzle 30 that is a movable part. FIG. 3 is a block diagram of a camera 70 and a control unit 9. FIG. 4 is a diagram illustrating an example of a flow of substrate processing in one cleaning processing unit 1 of the substrate processing apparatus 100. It is a figure which shows the picked-up image 82a-82d in each timing during shifting to a 2nd process from a 1st process. FIG. 4 is a diagram showing a first detection pattern of interference fringes ST. FIG. 9 is a diagram illustrating a second detection pattern of interference fringes ST. FIG. 9 is a diagram showing a third detection pattern of interference fringes ST. It is a figure showing the flow of processing which determines the 2nd processing start timing. FIG. 7 is a diagram showing a setting screen SW1 for setting conditions for detecting an interference fringe ST. FIG. 10 is a diagram illustrating a substrate processing apparatus 100A according to a second embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Note that the components described in this embodiment are merely examples, and are not intended to limit the scope of the present invention. In the drawings, the dimensions and the numbers of the respective parts may be exaggerated or simplified as necessary for easy understanding.

  Unless otherwise specified, expressions that indicate relative or absolute positional relationships (for example, "one direction", "along one direction", "parallel", "orthogonal", "center", "concentric", "coaxial", etc.) Not only the positional relationship is strictly expressed, but also a state in which the position is relatively displaced with respect to the angle or the distance within a range in which a function with a tolerance or a similar degree is obtained. Unless otherwise specified, expressions that indicate equal states (eg, "identical", "equal", "homogeneous", etc.) not only represent strictly equal states quantitatively, but also provide tolerances or similar functions. It is also assumed that a state where a difference exists exists. Unless otherwise specified, expressions indicating shapes (eg, “square shape” or “cylindrical shape”) not only represent the shape strictly geometrically, but also within a range where the same effect can be obtained, for example. A shape having irregularities and chamfers is also represented. The phrase “comprising,” “comprising,” “including,” “including,” or “having” one component is not an exclusive expression that excludes the presence of another component. Unless otherwise specified, "on" includes a case where two elements are in contact with each other and a case where two elements are distant from each other.

<1. First Embodiment>
FIG. 1 is a diagram illustrating an overall configuration of a substrate processing apparatus 100 according to the first embodiment. The substrate processing apparatus 100 is a single-wafer processing apparatus that processes substrates W to be processed one by one. The substrate processing apparatus 100 performs a cleaning process on a substrate W, which is a silicon substrate having a circular thin plate shape, using a rinsing solution such as a chemical solution and pure water, and then performs a drying process. As the chemical solution, for example, SC1 (ammonia-hydrogen peroxide mixture), SC2 (hydrochloric hydrogen peroxide mixed water solution), DHF solution (dilute hydrofluoric acid) and the like are used. Can be In the following description, the chemical liquid and the rinsing liquid may be collectively referred to as “treatment liquid”. Note that the substrate processing apparatus 100 supplies a coating liquid such as a photoresist liquid for a film formation processing, a chemical liquid for removing an unnecessary film, and a chemical liquid for etching, instead of a cleaning processing, to wet-process a substrate. It may be configured to do so.

  The substrate processing apparatus 100 includes a plurality of cleaning units 1, an indexer 102, and a main transfer robot 103.

  The indexer 102 transports the substrate W to be processed received from outside the apparatus into the apparatus, and unloads the processed substrate W after the completion of the cleaning processing to the outside of the apparatus. The indexer 102 mounts a plurality of carriers (not shown) and includes a transfer robot (not shown). As the carrier, a FOUP (Front Opening Unified Pod) or SMIF (Standard Mecanical InterFace) pod for accommodating the substrate W in a closed space, or an OC (Open Cassette) for exposing the substrate W to the outside air may be used. The transfer robot transfers the substrate W between the carrier and the main transfer robot 103.

  The cleaning processing unit 1 performs liquid processing and drying processing on one substrate W. In the substrate processing apparatus 100, twelve cleaning processing units 1 are arranged. Specifically, four towers each including three cleaning units 1 stacked in the vertical direction are arranged so as to surround the main transfer robot 103. FIG. 1 schematically shows one of the cleaning units 1 stacked in three stages. The number of cleaning units 1 in the substrate processing apparatus 100 is not limited to 12, and may be changed as appropriate.

  The main transfer robot 103 is installed at the center of the four towers on which the cleaning units 1 are stacked. The main transfer robot 103 loads the substrate W to be processed, received from the indexer 102, into each cleaning processing unit 1. The main transport robot 103 unloads the processed substrate W from each cleaning processing unit 1 and delivers it to the indexer 102.

<Cleaning unit 1>
Hereinafter, one of the twelve cleaning processing units 1 mounted on the substrate processing apparatus 100 will be described. However, the other cleaning processing units 1 are also different except that the arrangement relationship of the nozzles 30, 60, and 65 is different. It has the same configuration.

  FIG. 2 is a schematic plan view of the cleaning unit 1 according to the first embodiment. FIG. 3 is a schematic vertical sectional view of the cleaning unit 1 of the first embodiment. FIG. 2 shows a state where the substrate W is not held on the spin chuck 20, and FIG. 3 shows a state where the substrate W is held on the spin chuck 20.

  The cleaning unit 1 includes a spin chuck 20 that holds a substrate W in a horizontal position (a position in which the normal of the surface of the substrate W is along the vertical direction) in the chamber 10, and an upper surface of the substrate W held by the spin chuck 20. Nozzles 30, 60, and 65 for supplying a processing liquid to the substrate, a processing cup 40 surrounding the periphery of the spin chuck 20, and a camera 70 for imaging the space above the spin chuck 20. A partition plate 15 is provided around the processing cup 40 in the chamber 10 to vertically partition the inner space of the chamber 10.

  The chamber 10 includes a side wall 11 extending in a vertical direction and surrounding four sides, a ceiling wall 12 closing an upper side of the side wall 11, and a floor wall 13 closing a lower side of the side wall 11. The space surrounded by the side wall 11, the ceiling wall 12, and the floor wall 13 is a processing space for the substrate W. Further, a part of the side wall 11 of the chamber 10 is provided with a loading / unloading port for the main transfer robot 103 to load / unload the substrate W with respect to the chamber 10 and a shutter for opening / closing the loading / unloading port (both not shown). ing.

  A fan filter unit (FFU) 14 for further purifying air in a clean room where the substrate processing apparatus 100 is installed and supplying the air to a processing space in the chamber 10 is attached to the ceiling wall 12 of the chamber 10. . The FFU 14 includes a fan and a filter (for example, a HEPA filter) for taking in air in the clean room and sending the air into the chamber 10. The FFU 14 forms a downflow of clean air in the processing space in the chamber 10. In order to uniformly disperse the clean air supplied from the FFU 14, a punching plate having a number of blowout holes may be provided directly below the ceiling wall 12.

  The spin chuck 20 includes a spin base 21, a spin motor 22, a cover member 23, and a rotation shaft 24. The spin base 21 has a disk shape, and is fixed in a horizontal posture to an upper end of a rotating shaft 24 extending along the vertical direction. The spin motor 22 is provided below the spin base 21 and rotates the rotation shaft 24. The spin motor 22 rotates the spin base 21 via a rotation shaft 24 in a horizontal plane. The cover member 23 has a cylindrical shape surrounding the spin motor 22 and the rotation shaft 24.

  The outer diameter of the disc-shaped spin base 21 is slightly larger than the diameter of the circular substrate W held by the spin chuck 20. Therefore, the spin base 21 has a holding surface 21a facing the entire lower surface of the substrate W to be held.

  A plurality of (four in the present embodiment) chuck pins 26 are provided upright on the periphery of the holding surface 21 a of the spin base 21. The chuck pins 26 are arranged at equal intervals along the circumference corresponding to the outer diameter of the outer peripheral circle of the circular substrate W. In the present embodiment, four chuck pins 26 are provided at 90 ° intervals. Each of the chuck pins 26 is driven in conjunction with each other by a link mechanism (not shown) accommodated in the spin base 21. The spin chuck 20 holds the substrate W by bringing each of the chuck pins 26 into contact with the outer peripheral edge of the substrate W, thereby holding the substrate W in a horizontal posture close to the holding surface 21 a above the spin base 21. Hold (see FIG. 3). The spin chuck 20 releases the grip of the substrate W by separating each of the chuck pins 26 from the outer peripheral end of the substrate W. Each chuck pin 26 is a substrate holding unit that holds the substrate W in a horizontal posture.

  The cover member 23 that covers the spin motor 22 has its lower end fixed to the floor wall 13 of the chamber 10 and its upper end reaching directly below the spin base 21. At an upper end portion of the cover member 23, a flange-like member 25 that extends substantially horizontally outward from the cover member 23 and that bends downward and extends further is provided. With the spin chuck 20 holding the substrate W by the gripping by the plurality of chuck pins 26, the spin motor 22 rotates the rotation shaft 24 to rotate around the rotation axis CX along the vertical direction passing through the center of the substrate W. The substrate W can be rotated. The driving of the spin motor 22 is controlled by the control unit 9. In the following description, the horizontal direction orthogonal to the rotation axis CX is referred to as “radial direction”. The direction toward the rotation axis CX in the radial direction is referred to as “radially inward”, and the direction away from the rotation axis CX in the radial direction is referred to as “radially outward”.

  The nozzle 30 is configured by attaching a discharge head 31 to a tip of a nozzle arm 32. The base end of the nozzle arm 32 is fixedly connected to a nozzle base 33. A motor 332 (nozzle moving unit; see FIG. 4) provided on the nozzle base 33 is rotatable around a vertical axis.

  As the nozzle base 33 rotates, the nozzle 30 moves in the horizontal direction between a position above the spin chuck 20 and a standby position outside the processing cup 40 as indicated by an arrow AR34 in FIG. Move along the arc. Due to the rotation of the nozzle base 33, the nozzle 30 swings above the holding surface 21a of the spin base 21. More specifically, it moves to a predetermined processing position TP1 extending in the horizontal direction above the spin base 21. Moving the nozzle 30 to the processing position TP1 is synonymous with moving the ejection head 31 at the tip of the nozzle 30 to the processing position TP1.

  The nozzle 30 is configured to be supplied with a plurality of types of processing liquids (including at least pure water), and can discharge a plurality of types of processing liquids from the discharge head 31. Note that a plurality of ejection heads 31 may be provided at the tip of the nozzle 30, and the same or different treatment liquids may be individually ejected from each of them. The nozzle 30 (specifically, the discharge head 31) stops at the processing position TP1, and discharges the processing liquid. The processing liquid discharged from the nozzle 30 lands on the upper surface of the substrate W held by the spin chuck 20.

  The cleaning unit 1 of the present embodiment is provided with two nozzles 60 and 65 in addition to the nozzle 30 described above. The nozzles 60 and 65 of the present embodiment have the same or similar configuration as the nozzle 30 described above. That is, the nozzle 60 is configured by attaching a discharge head to the distal end of the nozzle arm 62, and the nozzle base 63 connected to the proximal end side of the nozzle arm 62 is provided above the spin chuck 20 as indicated by an arrow AR64. It moves in an arc between the processing position and the standby position outside the processing cup 40. The nozzle 65 is configured by attaching a discharge head to the tip of a nozzle arm 67, and a processing position above the spin chuck 20 as indicated by an arrow AR69 by a nozzle base 68 connected to the base end of the nozzle arm 67. And the standby position outside the processing cup 40 in an arc shape.

  A plurality of types of processing liquids including at least pure water are also supplied to the nozzles 60 and 65, and the processing liquid is discharged onto the upper surface of the substrate W held by the spin chuck 20 at the processing position. At least one of the nozzles 60 and 65 is a two-fluid nozzle that mixes a cleaning liquid such as pure water and a pressurized gas to generate droplets, and jets a mixed fluid of the droplets and the gas to the substrate W. It may be. Further, the number of nozzles provided in the cleaning processing unit 1 is not limited to three, but may be one or more.

  It is not essential to move each of the nozzles 30, 60, 65 in an arc shape. For example, the nozzle may be moved linearly by providing a direct drive unit.

  The nozzle 30 may be made of various kinds of water such as pure water (DIW) as a rinsing liquid, a water repellent such as IPA (Isopropyl Alcohol: isopropyl alcohol), a silylating agent, and DHF (Dilute HF: a mixed solution of hydrofluoric acid and pure water). It is connected to the supply source of the processing liquid, and can discharge various processing liquids separately from the discharge head 31 at the tip of the nozzle 30. Note that a plurality of ejection heads 31 may be provided at the tip of the nozzle 30, and each ejection head 31 may eject a different type of processing liquid. Further, the nozzles 60 and 65 may discharge a part of the above-described various processing liquids.

  A lower surface treatment liquid nozzle 28 is provided along the vertical direction so as to pass through the inside of the rotating shaft 24. The upper end opening of the lower processing liquid nozzle 28 is formed at a position facing the center of the lower surface of the substrate W held by the spin chuck 20. The lower processing liquid nozzle 28 is also configured to supply a plurality of types of processing liquid. The processing liquid discharged from the lower processing liquid nozzle 28 lands on the lower surface of the substrate W held by the spin chuck 20.

  The processing cup 40 surrounding the spin chuck 20 includes an inner cup 41, a middle cup 42, and an outer cup 43 that can be moved up and down independently of each other. The inner cup 41 has a shape that surrounds the periphery of the spin chuck 20 and is substantially rotationally symmetric with respect to a rotation axis CX passing through the center of the substrate W held by the spin chuck 20. The inner cup 41 has an annular bottom portion 44 in plan view, a cylindrical inner wall portion 45 rising upward from the inner peripheral edge of the bottom portion 44, a cylindrical outer wall portion 46 rising upward from the outer peripheral edge of the bottom portion 44, and an inner wall. The first guide portion 47 which rises from between the portion 45 and the outer wall portion 46 and extends obliquely upward at the center (in a direction approaching the rotation axis CX of the substrate W held by the spin chuck 20) while drawing a smooth arc at the upper end. And a cylindrical middle wall 48 rising upward from between the first guide portion 47 and the outer wall 46.

  The inner wall portion 45 is housed with an appropriate gap between the cover member 23 and the flange member 25 with the inner cup 41 raised most. The middle wall portion 48 is accommodated in a state where the inner cup 41 and the middle cup 42 are closest to each other, with an appropriate gap kept between a second guide portion 52 described later of the middle cup 42 and the processing liquid separation wall 53. You.

  The first guide portion 47 has an upper end portion 47b extending obliquely upward toward the center (in a direction approaching the rotation axis CX of the substrate W) while drawing a smooth arc. Further, between the inner wall portion 45 and the first guide portion 47, a disposal groove 49 for collecting and discarding the used processing liquid is formed. An annular inner collecting groove 50 for collecting and collecting used processing liquid is provided between the first guide portion 47 and the middle wall portion 48. Further, between the middle wall portion 48 and the outer wall portion 46, there is an annular outer collection groove 51 for collecting and collecting different types of processing liquids from the inner collection groove 50.

  An exhaust liquid mechanism (not shown) for discharging the processing liquid collected in the waste groove 49 and forcibly exhausting the waste groove 49 is connected to the waste groove 49. For example, four exhaust liquid mechanisms are provided at equal intervals along the circumferential direction of the waste groove 49. Further, the inner collecting groove 50 and the outer collecting groove 51 have a collecting mechanism for collecting the processing liquid collected in the inner collecting groove 50 and the outer collecting groove 51 into a collecting tank provided outside the substrate processing apparatus 100. (Both not shown) are connected. The bottoms of the inner recovery groove 50 and the outer recovery groove 51 are inclined by a small angle with respect to the horizontal direction, and the recovery mechanism is connected to the lowest position. Thus, the processing liquid flowing into the inner recovery groove 50 and the outer recovery groove 51 is smoothly recovered.

  The middle cup 42 has a shape that surrounds the periphery of the spin chuck 20 and is substantially rotationally symmetric with respect to a rotation axis CX passing through the center of the substrate W held by the spin chuck 20. The middle cup 42 has a second guide portion 52 and a cylindrical processing liquid separation wall 53 connected to the second guide portion 52.

  The second guide part 52 draws a smooth arc outside the first guide part 47 of the inner cup 41 from the upper end of the lower end part 52a which is coaxially cylindrical with the lower end part of the first guide part 47, and the lower end part 52a. It has an upper end portion 52b extending obliquely upward toward the center (in a direction approaching the rotation axis CX of the substrate W), and a folded portion 52c formed by folding the distal end portion of the upper end portion 52b downward. The lower end portion 52a is accommodated in the inner recovery groove 50 with an appropriate gap between the first guide portion 47 and the middle wall portion 48 in a state where the inner cup 41 and the middle cup 42 are closest to each other. The upper end portion 52b is provided so as to vertically overlap the upper end portion 47b of the first guide portion 47 of the inner cup 41, and when the inner cup 41 and the middle cup 42 are closest to each other, the first guide portion 47 is provided. Is kept close to the upper end portion 47b at a very small interval. The folded portion 52c horizontally overlaps the tip of the upper end portion 47b of the first guide portion 47 when the inner cup 41 and the middle cup 42 are closest to each other.

  The upper end portion 52b of the second guide portion 52 is formed such that the thickness increases toward the bottom. The processing liquid separation wall 53 has a cylindrical shape provided to extend downward from the outer peripheral edge of the lower end of the upper end 52b. The processing liquid separation wall 53 is accommodated in the outer recovery groove 51 with an appropriate gap between the middle wall portion 48 and the outer cup 43 with the inner cup 41 and the middle cup 42 being closest to each other.

  The outer cup 43 has a shape that is substantially rotationally symmetric with respect to a rotation axis CX passing through the center of the substrate W held by the spin chuck 20. The outer cup 43 surrounds the spin chuck 20 outside the second guide portion 52 of the middle cup 42. The outer cup 43 has a function as a third guide. The outer cup 43 has a lower end portion 43a coaxial with the lower end portion 52a of the second guide portion 52, and a central side (in a direction approaching the rotation axis CX of the substrate W) while drawing a smooth arc from the upper end of the lower end portion 43a. It has an upper end portion 43b extending obliquely upward and a folded portion 43c formed by folding a tip end of the upper end portion 43b downward.

  When the inner cup 41 and the outer cup 43 are closest to each other, the lower end portion 43a is formed with an outer collecting groove while maintaining an appropriate gap between the processing liquid separation wall 53 of the middle cup 42 and the outer wall portion 46 of the inner cup 41. 51. The upper end portion 43b is provided so as to overlap the second guide portion 52 of the middle cup 42 in the up-down direction, and when the middle cup 42 and the outer cup 43 are closest to each other, the upper end portion 43b is located on the upper end portion 52b of the second guide portion 52. Keep close together with very small intervals. In a state where the middle cup 42 and the outer cup 43 are closest to each other, the folded portion 43c overlaps the folded portion 52c of the second guide portion 52 in the horizontal direction.

  The inner cup 41, the middle cup 42, and the outer cup 43 can be raised and lowered independently of each other. That is, each of the inner cup 41, the middle cup 42, and the outer cup 43 is individually provided with an elevating mechanism (not shown), whereby the elevating mechanism is separately and independently elevated. As such an elevating mechanism, various known mechanisms such as a ball screw mechanism and an air cylinder can be adopted.

  The partition plate 15 is provided so as to vertically partition the inner space of the chamber 10 around the processing cup 40. The partition plate 15 may be a single plate member surrounding the processing cup 40, or may be a combination of a plurality of plate members. Further, the partition plate 15 may be formed with a through hole or notch penetrating in the thickness direction. In the present embodiment, the partition plate 15 supports the nozzle bases 33, 63, 68 of the nozzles 30, 60, 65. Are formed through the support shaft.

  The outer peripheral end of the partition plate 15 is connected to the side wall 11 of the chamber 10. The edge of the partition plate 15 surrounding the processing cup 40 is formed in a circular shape having a diameter larger than the outer diameter of the outer cup 43. Therefore, the partition plate 15 does not prevent the outer cup 43 from moving up and down.

  An exhaust duct 18 is provided in a part of the side wall 11 of the chamber 10 and near the floor wall 13. The exhaust duct 18 is connected to an exhaust mechanism (not shown). Of the clean air supplied from the fan filter unit 14 and flowing down in the chamber 10, the air passing between the processing cup 40 and the partition plate 15 is discharged from the exhaust duct 18 to the outside of the apparatus.

  FIG. 4 is a diagram illustrating a positional relationship between the camera 70 and the nozzle 30 that is a movable unit. The camera 70 is provided vertically above the substrate W in the vertical direction. The camera 70 includes, for example, a CCD, which is one of solid-state imaging devices, and an optical system such as an electronic shutter and a lens. The imaging direction of the camera 70 (that is, the optical axis direction of the imaging optical system) is set obliquely downward toward the rotation center of the upper surface of the substrate W (or in the vicinity thereof) in order to image the upper surface of the substrate W. The camera 70 covers the entire top surface of the substrate W held by the spin chuck 20 in its field of view. For example, in the horizontal direction, a range surrounded by a broken line in FIG.

  The camera 70 is installed so that its imaging visual field includes at least the tip of the nozzle 30 at the processing position TP1, that is, at a position including the vicinity of the ejection head 31. In the present embodiment, as shown in FIG. 4, the camera 70 is installed at a position where the nozzle 30 at the processing position TP1 is imaged from the upper front. Therefore, the camera 70 can capture an image of the imaging region including the tip of the nozzle 30 at the processing position TP1. Similarly, the camera 70 captures an image of an imaging region including each tip when the nozzles 60 and 65 are at the processing position when performing processing on the substrate W held on the spin chuck 20. When the camera 70 is installed at the position shown in FIGS. 2 and 4, the nozzles 30 and 60 move in the horizontal direction within the imaging field of view of the camera 70, so that the tips of the nozzles 30 and 60 at each processing position Can be properly imaged, but since the nozzle 65 moves in the depth direction within the field of view of the camera 70, the movement near the processing position may not be properly imaged. In this case, a camera for imaging the nozzle 65 may be provided separately from the camera 70.

  The nozzle 30 is driven by the nozzle base 33 to move the processing position TP1 (the position indicated by the broken line in FIG. 4) above the substrate W held by the spin chuck 20 and the standby position outside the processing cup 40 (FIG. 4). (Solid line position). The processing position TP1 is a position where the cleaning liquid is discharged from the nozzle 30 onto the upper surface of the substrate W held by the spin chuck 20 to perform the cleaning processing. The processing position TP1 is a position near the center (the rotation axis CX) of the substrate W held by the spin chuck 20. The standby position is a position where the nozzle 30 stops discharging the processing liquid and waits when the nozzle 30 does not perform the cleaning process. The standby position is a position deviated from above the spin base 21 and a position outside the processing cup 40 in a horizontal plane. A standby pod that accommodates the ejection head 31 of the nozzle 30 may be provided at the standby position.

  Note that the processing position TP1 may be an arbitrary position such as a position near the edge of the substrate W. Further, the processing position TP1 is at a position deviating from the substrate W (that is, does not vertically overlap with the substrate W). State). In the latter case, the processing liquid discharged from the nozzle 30 may be scattered from outside the substrate W onto the upper surface of the substrate W. It is not essential that the processing liquid be ejected from the nozzle 30 while the nozzle 30 is stopped at the processing position TP1. For example, while discharging the processing liquid from the nozzle 30, the nozzle 30 may be moved within a predetermined processing section extending in the horizontal direction above the substrate W with the processing position TP1 as one end.

  As shown in FIG. 3, an illumination unit 71 is provided in the chamber 10 at a position above the partition plate 15. The illumination unit 71 includes, for example, an LED lamp as a light source. The illumination unit 71 supplies illumination light required for the camera 70 to image the inside of the chamber 10 to the processing space. When the inside of the chamber 10 is a dark room, the control unit 9 may control the illumination unit 71 so that the illumination unit 71 irradiates the nozzles 30, 60, 65 with light when the camera 70 performs imaging. The illumination unit 71 emits visible light as illumination light. However, the illumination light is not limited to visible light. As the irradiation light, for example, an infrared ray having a wavelength of about 0.7 μm-1 mm, more preferably a near infrared ray having a wavelength of about 0.7 μm-2.5 μm can be employed. In this case, as the camera 70, an infrared camera provided with an infrared sensor that detects infrared rays (more preferably, near infrared rays) can be adopted. By detecting infrared rays, interference fringes can be suitably detected.

  FIG. 5 is a block diagram of the camera 70 and the control unit 9. The configuration of the control unit 9 provided in the substrate processing apparatus 100 as hardware is the same as that of a general computer. That is, the control unit 9 includes a CPU that performs various arithmetic processes, a ROM that is a read-only memory that stores a basic program, a RAM that is a readable and writable memory that stores various information, and control software (program) and data. It has a magnetic disk and the like for storing. When the CPU of the control unit 9 executes a predetermined processing program, the operation of each element of the substrate processing apparatus 100 is controlled by the control unit 9 and the processing in the substrate processing apparatus 100 proceeds.

  The determination area setting unit 91 and the timing determination unit 92 shown in FIG. 5 are functions realized by the CPU of the control unit 9 operating according to the control software.

  The determination area setting unit 91 sets a determination area DR on the captured image 82 acquired by the camera 70. The size, position, number, and the like of the determination region DR may be determined in advance, or may be set based on an operator's designation.

  After the previous processing (first processing) of processing the substrate W with the liquid, the timing determination unit 92 starts the subsequent processing (second processing) by detecting the interference fringes ST appearing on the upper surface of the substrate W. (Hereinafter, also referred to as “second processing start timing”). As described later, the timing determination unit 92 detects each interference fringe ST in the determination area DR set in the captured image 82. Further, as described later, the detection of the interference fringe ST in the determination region DR is performed by the extreme point detecting unit 921 included in the timing determining unit 92 detecting the extreme point of the luminance value.

  The control unit 9 includes a storage unit 96 including the above-described RAM or magnetic disk. The storage unit 96 stores image data obtained by the camera 70, input values of the operator, and the like.

  The display unit 97 and the input unit 98 are connected to the control unit 9. The display unit 97 displays various information according to the image signal from the control unit 9. The input unit 98 includes an input device such as a keyboard and a mouse connected to the control unit 9 and receives an input operation performed by the operator on the control unit 9.

<Operation description>
FIG. 6 is a diagram illustrating an example of a flow of substrate processing in one cleaning processing unit 1 of the substrate processing apparatus 100. Each step described below is performed under the control of the control unit 9 unless otherwise specified.

  First, in a state where the nozzle 30 is at the retracted position, the main transport robot 103 loads the substrate W to be processed received from the indexer 102 into the chamber 10 of any one of the cleaning processing units 1 (Step S10). The substrate carried into the chamber 10 is placed on each of the chuck pins 26 of the spin base 21. When the chuck pins 26 are closed, the substrate W is held in a horizontal posture. When the substrate W is carried in, the rotation of the substrate W is started by the spin motor 22.

  Subsequently, the nozzle 30 moves to the processing position TP1 and supplies various processing liquids to the substrate W, thereby performing liquid processing on the substrate W. Here, first, a hydrofluoric acid process for supplying hydrofluoric acid from the nozzle 30 to the upper surface of the substrate W is performed (step S11). The hydrofluoric acid supplied to the upper surface of the substrate W spreads to the outer edge of the substrate W by the rotation of the substrate W, and the hydrofluoric acid process proceeds on the entire substrate W. The period during which hydrofluoric acid is supplied to the substrate W is, for example, 30 seconds. The rotation speed of the substrate W during this period is, for example, 800 rpm (revolution per minute: rotation speed / minute).

  After the discharge of hydrofluoric acid from the nozzle 30 is stopped, a rinsing process for supplying a rinsing liquid (DIW) from the nozzle 30 to the upper surface of the substrate W is performed (Step S12). During the rinsing process, the rinsing liquid is continuously supplied from the nozzle 30 to the upper surface of the rotating substrate W. The rinsing liquid supplied to the upper surface of the substrate W spreads to the outer edge of the substrate W by the rotation of the substrate W. Then, the hydrofluoric acid remaining on the upper surface of the substrate W is shaken radially outward from the outer edge of the substrate W. The hydrofluoric acid and the rinsing liquid shaken off from the substrate W are received by the processing cup 40 and are appropriately discarded. The period during which the rinsing liquid is supplied to the substrate W is, for example, 30 seconds. The rotation speed of the substrate W during this period is, for example, 1200 rpm.

  After the discharge of the rinsing liquid from the nozzle 30 is stopped, an IPA process of supplying IPA from the nozzle 30 to the upper surface of the substrate W is performed (Step S13). At the time of the IPA processing, in the IPA processing, IPA is continuously supplied to the upper surface of the substrate W rotating from the nozzle 30. The IPA supplied to the upper surface spreads to the outer edge of the substrate W by the rotation of the substrate W, and the rinsing liquid (DIW) is replaced with the IPA on the entire upper surface. Further, a heat treatment may be performed on the substrate W by a heating mechanism (not shown) for the purpose of promoting the IPA replacement. The period during which the IPA is supplied is, for example, 30 seconds. The rotation speed of the substrate W during this period is, for example, 300 rpm.

  After the discharge of the IPA from the nozzle 30 is stopped, a water repellent process of supplying a water repellent from the nozzle 30 to the upper surface of the substrate W is performed (Step S14). The water repellent supplied to the upper surface of the substrate W spreads to the outer edge of the substrate W by the rotation of the substrate W, and the entire upper surface is replaced with IPA by the water repellent, and the upper surface is converted to water repellent. The water-repellent treatment to be performed proceeds. The period during which the water repellent is supplied is, for example, 30 seconds. The rotation speed of the substrate W during this period is, for example, 500 rpm.

  After the discharge of the water repellent from the nozzle 30 is stopped, the same IPA processing as in step S13 is performed (step S15). By the IPA processing, the water repellent remaining on the upper surface of the substrate W is replaced with the IPA processing liquid.

  After the discharge of IPA from the nozzle 30 is stopped, the nozzle 30 is moved from the processing position TP1 to the retreat position. Then, a spin dry process is executed (step S16). In the spin dry process, the spin motor 22 rotates the substrate W at a higher rotation speed than in the respective liquid processes in steps S12 to S16. The rotation speed at this time is, for example, 1500 rpm. The various liquids adhered to the substrate W by the spin dry process are scattered radially outward from the outer peripheral portion, received by the inner wall of the processing cup 40, and are appropriately drained.

  When the spin dry process ends, the holding of the substrate W by the chuck pins 26 is released, and the main transport robot 103 unloads the substrate W from the chamber 10 (Step S17).

  As described above, the processing by the cleaning processing unit 1 includes a liquid processing step of performing liquid processing on the substrate W (steps S11 to S15) and a drying processing of drying the substrate W (step S16).

  In the above description, all the liquid treatments are described as being discharged from the nozzles 30. However, some processing liquids may be discharged from the nozzles 60 and 65. In this case, the nozzles 60 and 65 may be moved from the retreat position to the processing position at appropriate timing, and various processing liquids may be discharged from the nozzles 60 and 65 onto the upper surface of the substrate W.

<Regarding the process for determining the second process start timing>
In the substrate processing apparatus 100, after the liquid processing using the liquid (the first processing) is completed, and before the next processing (the second processing) is started, the timing determination unit 92 determines the timing at which the next processing is started. . For example, after the discharge of IPA from the nozzle 30 in the IPA process (first process) in step S13 is stopped, the timing determination unit 92 determines that the nozzle 30 in the next process of water repellency (second process) has water repellency. The second processing start timing at which the discharge of the agent is started is determined. As described above, the timing determination unit 92 determines the timing at which the next processing is executed in accordance with the detection of the interference fringe ST. Here, the interference fringes ST appearing on the upper surface of the substrate W will be described.

  FIG. 7 is a diagram showing captured images 82a-82d at each timing during the transition from the first processing to the second processing. The captured image 82a shows a state in which the processing liquid is supplied to the upper surface of the substrate W from the nozzle 30 in the first processing. When the processing liquid is supplied to the upper surface of the rotating substrate W from the nozzle 30 or the like, the processing liquid moves radially outward on the upper surface of the substrate W, and drops or radially outwards from the outer edge of the substrate W. Shake off. At this time, by balancing the amount of the processing liquid supplied to the substrate W and the amount of the processing liquid which is shaken outward by the rotation of the substrate W, the liquid film W1 which is a film of the processing liquid is formed on the upper surface of the substrate W. Is formed.

  The captured image 82b shows the state of the upper surface of the substrate W when a predetermined time has elapsed since the supply of the processing liquid from the nozzle 30 was stopped. When the supply of the processing liquid is stopped in a state where the liquid film W1 is formed, the processing liquid on the surface of the substrate W is scattered radially outward, so that the liquid film W1 is gradually thinned. In the process of reducing the film thickness, light reflected on the upper surface of the substrate W and light reflected on the surface of the liquid film W1 interfere with each other. Then, a portion where the phases of these two lights coincide with each other appears as a bright band region, and a portion where the phases are opposite appears as a dark band region. As shown in the photographed image 82b, bright and dark stripes appear alternately in the radial direction, so that bright and dark stripes are observed. Here, one dark band area is defined as an interference fringe ST. However, a bright band area may be regarded as an interference fringe.

  As the substrate W rotates, the processing liquid in the center moves toward the outer edge. Therefore, in the process of thinning the liquid film, each interference fringe ST appears on the substrate W in an annular band shape (loop shape) and moves while spreading radially outward. Note that the interference fringes ST do not always appear in a perfect annular shape.

  The photographed image 82c shows the state of the upper surface of the substrate W when the time further elapses from the state shown in the photographed image 82b. As time passes, the interval between radially adjacent interference fringes ST gradually increases. As shown in the photographed image 82c, for example, when the number of interference fringes ST simultaneously appearing on the substrate W becomes about three, the substrate W is in a state of being covered with the liquid film W1 having a thickness close to the minimum. When the state of such a stripe pattern is used as a guide for the start of the next processing, the second processing start timing is appropriately determined by setting at least one of the interference fringes ST constituting the stripe pattern as a detection target. it can.

  The photographed image 82d shows a state of the upper surface of the substrate W when a further time has elapsed from the state shown in the photographed image 82c. In the captured image 82d, the last interference fringe STL appears on the substrate W. In the area inside the interference fringe STL, there is a possibility that a dry area having no liquid component is partially generated.

  Here, it is assumed that the second processing performed after the first processing is a liquid processing using a second processing liquid. In this case, if the second processing liquid is supplied in a state where the liquid film W1 of the first processing liquid is thick as in the captured images 82a and 82b, it may take time to replace the first processing liquid with the second processing liquid. Further, when the second processing liquid is supplied in a state where the dry area is partially generated as in the photographed image 82d, the time of exposure to the second processing liquid differs depending on the position of the substrate W. 2 There is a possibility that the processing will vary.

  Further, when the second process is a drying process such as a spin dry process, when a dry region is partially generated as in the captured image 82d, the first processing liquid may be present in a small amount locally. In such a case, there is a possibility that it takes a long time to shake off even when shifting to high-speed rotation. Therefore, it may be preferable to start high-speed rotation before the state of the captured image 82d (that is, the state in which the last interference fringe STL has appeared). In contrast to this, when the liquid film W1 of the first processing liquid shifts to high-speed rotation as in the captured images 82a and 82b, the movement of the first processing liquid in the radially outward direction is biased. There is a possibility that the processing liquid that has been shaken off may collide with the processing cup 40 or the like and contaminate the inside of the chamber 10. Therefore, it may be preferable to start the high-speed rotation after reducing the thickness of the liquid film W1 as much as possible.

  By appropriately setting the interference fringes ST to be detected by the timing determining unit 92 in advance in accordance with the contents of each of the first and second processes, the timing determining unit 92 can appropriately determine the second process start timing. . Next, a detection pattern of the interference fringe ST will be described.

<First detection pattern>
FIG. 8 is a diagram illustrating a first detection pattern of the interference fringe ST. The first detection pattern is a mode in which the determination area setting unit 91 sets one determination area DR11 on the captured image 82. The determination region DR11 is set on the upper surface of the substrate W on which the liquid film W1 is formed. The vertical position of the determination region DR11 matches the center of the substrate W in the captured image 82. As the interference fringes ST move radially outward, the interference fringes ST pass in the horizontal direction of the captured image 82 in the determination region DR11.

  As shown in FIG. 8, the determination region DR11 is set to a size that can overlap only one interference fringe ST to be detected. For example, the radial width of the determination region DR11 (the horizontal width on the captured image 82) is smaller than the radial interval between adjacent interference fringes ST. Note that the interval between the interference fringes ST changes according to the thickness of the liquid film W1. For example, the interval between the interference fringes ST is relatively small when the liquid film W1 is thick as shown in the captured image 82b of FIG. 7, and between the interference fringes ST when the liquid film W1 is thin as shown in the captured image 82c. The spacing is relatively large. The size of the determination region DR11 may be set according to the width between the interference fringes ST when the interference fringes ST to be detected appear.

  Here, a region where the light intensity is relatively weak with respect to the surroundings is defined as an interference fringe ST. Therefore, when passing through the determination region DR11, the luminance indicating the light intensity in the horizontal direction in the determination region DR11 gradually decreases from the radially inner side to the outer side and then increases again as shown in FIG. Become. The point at which the luminance becomes the minimum value corresponds to a point substantially at the center of the interference fringe ST. For this reason, the passage of the interference fringe ST in the determination region DR11 can be detected by the extreme point detection unit 921 detecting the extreme point at which the brightness has the minimum value in the determination region DR11.

  When a bright portion (a region where the light intensity is relatively large on the captured image 82) is captured as interference fringes, a bright (that is, a large light intensity) band-like region moves radially outward. In this case, the extreme value detection unit 921 may detect an interference value that is a bright part in the determination region DR11 by detecting an extreme value point at which the light intensity (luminance) in the radial direction becomes a maximum value.

  In the case of the first detection pattern, the timing determination unit 92 determines the first detection time at which the n-th (n is a natural number) interference fringe ST (first extreme value point) is detected, and the interference fringes generated after the (n + 1) -th time A detection time difference, which is a difference from a second detection time at which ST (second extreme point) is detected, is calculated. Here, the second detection time may be a time during which the (n + 1) th interference fringe ST is detected, or a time during which the (n + 2) th interference fringe ST occurring thereafter is detected. Since the interval between the interference fringes ST changes according to the thickness of the liquid film W1, it is considered that the detection time difference corresponds to the thickness of the liquid film W1. For example, as the thickness of the liquid film W1 decreases, the detection time difference increases. Therefore, for example, the optimal detection time difference corresponding to the optimal thickness of the liquid film W1 at the start of the second processing may be experimentally determined. Then, when the actually detected detection time reaches the optimum detection time, the timing determination unit 92 may determine that the interference fringe ST to be detected has been detected and determine the second processing start timing. .

  Further, it may be determined whether or not the interference fringe ST to be detected is detected based on each detection time of three or more interference fringes ST in the determination region DR11. For example, the first detection time difference between the first interference fringe ST (first extreme point) and the second interference fringe ST (second extreme point) and the second interference fringe ST (second extreme point) ) And a second detection time difference between the third interference fringe ST (third extreme point). Then, the second processing start timing may be determined based on the comparison between the first and second detection time differences. More specifically, when the difference between the first detection time and the second detection time difference reaches a predetermined value, it is determined that the interference fringe ST to be detected has been detected, and the second processing is started based on the time. The timing may be determined.

  As described above, the interval between the interference fringes ST gradually increases as the liquid film W1 becomes thinner, that is, as the liquid crystal film W1 approaches the appearance time of the last interference fringe STL. For this reason, in the case of the first detection pattern, the number of frames acquired from the passage of one interference fringe ST to the passage of the next interference fringe ST in the determination area DR11 gradually increases. The accuracy is improved. Therefore, as the liquid film W1 becomes thinner, the timing determining unit 92 can appropriately determine whether the detection time difference corresponds to the target film thickness.

  The interference fringe ST generated when the liquid film W1 is thin (for example, the interference fringe STL appearing last in the captured image 82d shown in FIG. 7) may not be clearly detected due to noise such as fluctuation of the liquid surface. is there. Therefore, it is desirable that the interference fringes ST that can be detected as clearly as possible be detected. Further, a time obtained by adding a predetermined delay time to the time when the clear interference fringe ST is detected may be set as the second processing start timing. Thereby, the interference fringe ST to be detected can be detected with high accuracy, and the second processing can be started after the liquid film W1 has a suitable thickness.

<Second detection pattern>
FIG. 9 is a diagram illustrating a second detection pattern of the interference fringe ST. In the second detection pattern, the determination area setting unit 91 sets a plurality of determination areas DR21 to DR23. In the example shown in FIG. 9, three determination regions DR21 to DR23 are set in order from the inside in the radial direction to the outside. Note that the number of determination regions DR is not limited to three, and may be two or four or more.

  Each of the determination areas DR21 to DR23 is arranged at intervals in the horizontal direction of the captured image 82. The vertical positions of the determination regions DR21 to DR23 coincide with the center of the substrate W in the captured image 82. The interference fringe ST moves radially outward to pass through the respective determination regions in the order of the determination region DR21, the determination region DR22, and the determination region DR23.

  Each of the determination areas DR21 to DR23 is set to a size that does not include a plurality of interference fringes ST at the same time as in the determination area DR11 of FIG. For example, the horizontal width of each determination region DR is smaller than the radial interval between adjacent interference fringes ST.

  The intervals at which the determination regions DR21 to DR23 are arranged may be set in accordance with the intervals between the plurality of interference fringes ST to be detected. Specifically, it may be set according to the number of interference fringes ST to be detected on the upper surface of the substrate W and the interval between the interference fringes ST.

  For example, as shown in FIG. 9, when the detection target is three interference fringes ST (interference fringes ST1 to ST3) appearing at the illustrated intervals, three determination regions are set in accordance with the intervals of the three interference fringes ST. DR21-DR23 are arranged. Thereby, in the determination regions DR21 to DR23, three interference fringes ST to be detected simultaneously can be simultaneously detected. That is, when the extremum point detection unit 921 detects the extremum point having the minimum value in all of the determination regions DR21 to DR23, the timing determination unit 92 may determine that each interference fringe ST to be detected is detected.

  The positions of the determination areas DR21 to DR23 may be arbitrarily set by the operator. In this case, for example, a captured image 82 in which each of the interference fringes ST to be detected has appeared is acquired in advance, and a frame indicating the determination regions DR21 to DR23 is placed on the captured image 82 at the position of each of the interference fringes ST. Move it. Thereby, each determination area DR21-DR23 can be set at each position where each target interference fringe ST is simultaneously detected.

  In particular, the three interference fringes ST counted from the last interference fringe STL may be the three interference fringes ST1 to ST3 to be detected. That is, the last interference fringe STL may be the innermost interference fringe ST1 to be detected, and the two detection fringes ST generated immediately before the last interference fringe STL may be the interference fringes ST2 and ST3 to be detected. In this case, the timing at which the second processing is performed can be determined before the liquid film W1 becomes thin before the interference fringe ST becomes undetectable. The last interference fringe STL corresponds to the last extreme point that can be detected last.

<Third detection pattern>
FIG. 10 is a diagram illustrating a third detection pattern of the interference fringe ST. In the third detection pattern, the determination area setting unit 91 sets one determination area RD31 on the captured image 82. The determination region RD31 has a shape extending in the radial direction (here, a rectangular shape extending in the horizontal direction in the captured image 82). The determination area RD31 is set to a size that can overlap with the plurality of interference fringes ST to be detected at the same time.

  In the third detection pattern, the extremum point detection unit 921 detects an extremum point having an extremum, which is an extremum, in the determination region DR31. The timing determination unit 92 detects the interference fringe ST to be detected by specifying the extreme value point having the minimum value in the determination region DR31. Specifically, the timing determination unit 92 detects the interference fringe ST to be detected based on the distance between extreme points calculated in the determination region DR31. The distance between extreme points refers to a distance between points where the luminance becomes a minimum value in the determination region DR31. In the example shown in FIG. 10, the detection target is three interference fringes ST1-ST3. In this case, the distances L1 and L2 corresponding to the intervals between these three interference fringes ST1 to ST3 are set in advance, and the timing determination unit 92 determines that the distance between the extreme points detected in the determination region DR31 is L1. , L2. When the interference fringes ST1 to ST3 are present in the determination region DR31, the interference fringes ST1 to ST3 to be detected are detected by determining that the distance between the extreme points corresponds to L1 and L2.

  Note that the timing determination unit 92 may detect the interference fringe ST to be detected based on the number of extreme points detected in the determination region DR31. In the example shown in FIG. 9, the detection target is three interference fringes ST1-ST3. Therefore, when three extreme points are detected in the determination region DR31, the timing determination unit 92 may determine that the interference fringes ST1 to ST3 to be detected have been detected.

  The second processing start timing may be determined based on the comparison between the extreme point distances L1 and L2. For example, when the difference between the extreme point distances L1 and L2 becomes a predetermined value, it may be determined that the detection target stripes ST1 to ST3 have been detected.

  FIG. 11 is a diagram illustrating a flow of processing for determining the second processing start timing. In the flow shown in FIG. 11, the IPA process (FIG. 6: step S13) is a first process, and the water repellent process (FIG. 6: step S14) is a second process, and the second process start timing (discharge of the water repellent agent) Is shown.

  In the IPA process (FIG. 6: step S13), IPA is supplied from the nozzle 30 to the upper surface of the substrate W (step S21). During this time, the camera 70 performs continuous shooting (step S22). The continuous imaging means that the camera continuously captures an image of the imaging region at a constant interval, and it is preferable to perform the continuous imaging at an interval of, for example, 33 milliseconds. By this continuous photographing, a photographed image 82 obtained by imaging the state of the upper surface of the substrate W is obtained.

  When the continuous imaging is started, the determination area setting unit 91 sets a determination area DR for the acquired captured image 82 (Step S23). The determination area DR set in step S23 differs depending on the detection pattern of the interference fringe ST to be detected. For example, in the case of the first detection pattern described with reference to FIG. 8, one determination region DR11 is set for the captured image 82.

  It is not essential that continuous imaging be started while IPA is being ejected. For example, continuous imaging may be performed from the time when the substrate W is carried into the chamber 10 to the time when it is carried out.

  When the determination region DR is set, the supply of the IPA from the nozzle 30 to the substrate W is stopped (Step S24). At this point, the IPA process (FIG. 6: step S13) is completed. As described above, when the supply of the IPA is stopped, the IPA on the substrate W is swung radially outward by the centrifugal force. As a result, the liquid film W1 becomes thinner gradually, and interference fringes ST begin to appear.

  The extremum point detection unit 921 detects an extremum point that takes the minimum value of the luminance in the radial direction in the determination region DR (Step S25). As a result, the interference fringe ST overlapping the determination region DR is detected as an extreme point having a minimum value.

  Based on the detection result of the minimum value by the extreme point detection unit 921, the timing determination unit 92 determines whether or not the interference fringe ST to be detected is detected (Step S26). The specific content of this determination differs depending on the detection pattern of the interference fringe ST. When it is determined that the interference fringe ST to be detected has not been detected (NO in step S26), the process returns to step S25, and the detection of the minimum value is continuously performed.

  For example, in the case of the first detection pattern illustrated in FIG. 8, the timing determination unit 92 determines the detection target when the detection time difference between the interference fringes ST detected in the determination area DR11 corresponds to a preset optimal detection time difference. It is determined that the interference fringe ST has been detected. In the case of the second detection pattern illustrated in FIG. 9, the timing determination unit 92 determines that the interference fringes ST1 to ST3 to be detected are detected when the interference fringes ST are simultaneously detected in the determination regions DR21 to DR23. judge. In the case of the third detection pattern shown in FIG. 10, the timing determination unit 92 determines that the distance between the extreme points between the points where the minimum value is detected corresponds to the predetermined distances L1 and L2 in the determination area DR31. Then, it is determined that the interference fringes ST1 to ST3 to be detected have been detected.

  Returning to FIG. 11, when the timing determination unit 92 determines that the interference fringe ST to be inspected has been detected (YES in step S26), the timing determination unit 92 determines the second processing start timing (step S27). The timing determination unit 92 determines the start timing according to the detection completion time when the interference fringe ST to be detected is detected (the time when the minimum value corresponding to the interference fringe ST to be detected is detected). For example, the timing determination unit 92 sets a time obtained by adding a predetermined delay time from the detection completion time as a start timing.

  When the start timing is determined in step S27, the discharge of the water repellent from the nozzle 30 onto the upper surface of the substrate W is started at the start timing (step S28). Thereby, the water-repellent treatment (FIG. 6: step S14) is started. In step S28, the control unit 9 causes the nozzle 30 to discharge the water-repellent agent as the next process according to the timing determined by the timing determination unit 92. That is, the control unit 9 executes a water repellent process, which is the next process, according to the start timing. For this reason, the control unit 9, the nozzle 30, and the mechanism for supplying the water repellent to the nozzle 30 can be an example of the second processing execution unit.

  In step S27, the length of the delay time added from the detection completion time to determine the start timing may be determined in advance by experimental substrate processing. Specifically, after the interference fringe ST to be detected is detected, the water-repellent treatment is started at a different delay time, and the resulting hydrophobic state of the substrate W is evaluated. An optimum delay time may be determined based on this evaluation result.

  In step S27, it is not essential that the start timing be a time obtained by adding a predetermined delay time from the detection completion time. For example, the start timing may be the detection completion time. In this case, when it is determined in step S26 that the interference fringe ST to be detected is detected, the discharge of the water repellent is started immediately.

  In FIG. 11, when the first process is the IPA process and the second process is the water-repellent process, the process is a process of determining the start timing of the second process. However, the combination of the first process and the second process is not limited to this. It is not something to be done. For example, the start timing determination process is also applied when the first process is the IPA process after the water repellent process (FIG. 6: step S15) and the second process is the spin dry process (FIG. 6: step S16). It is possible. In this case, the control unit 9 controls the spin motor 22 of the spin chuck 20 according to the start timing determined by the timing determination unit 92, thereby increasing the rotation speed of the substrate W from 300 rpm to 1500 rpm. That is, the control unit 9 executes the spin dry process as the second process according to the start timing. For this reason, the control unit 9 and the spin motor 22 can be a second processing unit.

<Effect>
According to the substrate processing apparatus 100, the second processing can be executed at an appropriate timing on the substrate W on which the first processing as the liquid processing has been performed.

  If the second process is a liquid process (for example, the first process is an IPA process (FIG. 6: step S13) and the second process is a water-repellent process (FIG. 6: step S14)), the first process is performed. The second processing liquid can be supplied after the film thickness of the processing liquid is made as thin as possible. In this case, since the amount of the first processing liquid on the substrate can be reduced, replacement with the second processing liquid can be promoted. Thereby, the processing time of the second processing can be reduced. Further, since the amount of the second processing liquid used can be reduced, the cost of substrate processing can be reduced.

  When the second process is a drying process (the first process is an IPA process (FIG. 6: step S15) and the second process is a spin dry process (step S16)), the substrate processing apparatus According to 100, it is possible to shift to the drying process when the film thickness of the first processing liquid is appropriate. For this reason, excessive swelling of the liquid film can be suppressed. Thereby, the substrate surface can be uniformly processed.

<Condition setting for detecting interference fringe ST>
FIG. 12 is a diagram showing a setting screen SW1 for setting conditions for detecting the interference fringes ST. In the substrate processing apparatus 100, on a processing program creation screen (not shown) displayed on the display unit 97, processing for determining the processing content to be executed by each operator in each cleaning processing unit 1 is performed. The setting screen SW1 is a screen displayed after shifting from the processing program creation screen.

  The setting screen SW1 is displayed as a window displayed on the entire screen of the display unit 97 or a part thereof. When the operator performs a predetermined operation on the setting screen SW1, the determination area setting unit 91 sets the conditions of the determination area DR according to the operation input. In step S23 shown in FIG. 11, the determination area setting unit 91 sets a determination area DR that matches the set conditions on the captured image 82 for detecting the interference fringe ST to be detected.

  In the setting screen SW1, display areas DA1 to DA6 for displaying various information are defined. The contents of the first processing and the second processing are displayed in the display area DA1. The display area DA1 contains the contents of the designated processing, such as the type of processing liquid, the discharge amount of the processing liquid, the discharge time of the processing liquid, and the number of rotations of the substrate W at the time of discharging the processing liquid. Each parameter is displayed. In the display area DA1, a change in each parameter may be accepted based on an input operation by the operator. When the operator specifies the processing content of the first processing or the second processing in the display area DA1, the second processing start timing is determined. In the display area DA1, an area indicating a detection pattern and a position pattern selected in display areas DA2 and DA3 described later is defined.

  When the first and second processes are set, the timing determination unit 92 automatically determines the interference fringe ST to be detected based on the processing conditions. As preliminary preparations for this determination processing, the interference fringe ST to be detected may be specified in advance for each of the different conditions for the first processing. In this case, in each case where the first processing is performed while changing the conditions of the processing liquid, the discharge amount, and the rotation speed, a suitable start timing of the second processing is determined, and the interference fringe ST corresponding to the start timing is determined. It should be decided.

  Buttons BT11-BT14 for selecting a detection pattern are displayed in display area DA2. Each of the buttons BT11 to BT13 is an operation unit for setting the detection pattern of the interference fringe ST to any of the above-described first to third detection patterns (see FIGS. 8 to 10). When the operator operates any of the buttons BT11 to BT13, the corresponding detection pattern is selected. Here, the first detection pattern is selected by operating the button BT11, and a display indicating the selection result is displayed in the display area DA1. The button BT14 is an operation unit for automatically setting a detection pattern. When the button BT14 is operated, any one of the first to third detection patterns is automatically selected.

  In the display area DA3, buttons BT21 to BT24 for selecting a position pattern of the determination area DR are displayed. When the operator operates any of the buttons BT21 to BT24, the position pattern of the determination area DR is set according to the operated button. The contents assigned to the buttons BT21 to BT23 may be set in advance for each detection pattern selected in the display area DA2. For example, in the case of the first detection pattern, the position (for example, the position in the radial direction) where one determination region DR11 is arranged may be different between the buttons BT21 and BT23. In the case of the second detection pattern, the intervals in the radial direction between the respective determination regions DR21 and DR23 may be different between the buttons BT21 and BT23.

  When the button BT24 is operated, the determination area setting unit 91 automatically sets the position of the determination area DR. For example, the determination area setting unit 91 may set the determination area DR at a position that is predetermined as an initial value, or may set the position of the determination area DR based on a predetermined determination criterion. In the latter case, the determination area may be set at a position suitable for detecting the interference fringe ST according to the interference fringe ST to be detected.

  In the display area DA4, buttons BT31 to BT33 for selecting the type of the substrate W to be processed are displayed. The type of the substrate W includes, for example, the size of the substrate W, the presence or absence of a structure such as a circuit pattern on the upper surface of the substrate W, and the affinity (hydrophobic / hydrophilic) of water on the upper surface of the substrate W. It is preferable to correspond to each state affecting the appearance.

  The captured image 82 is displayed in the display area DA5. This photographed image 82 may be a photographed image obtained by photographing with the camera 70 in the past, or may be a photographed image obtained by photographing with the camera 70 in real time. Preferably, a rectangular frame indicating the determination area DR is displayed on the captured image 82 according to the detection pattern and the position pattern selected in the display areas DA2 and DR3. For example, when the first detection pattern is selected, one determination region DR11 may be displayed.

  An operation to change the position of the determination region DR on the captured image 82 may be received. For example, the determination region DR may be changed to the moved position by receiving a drag operation. The operation of moving the determination region DR may be changed only in one direction corresponding to the radial direction (here, the horizontal direction of the captured image 82). In this case, the position of the determination region DR can be changed in accordance with the moving direction (radially outward) of the interference fringe ST, so that the determination region DR can be easily set.

  When the captured image 82 obtained by the past imaging is displayed, the captured image 82 is at the time of shifting from the first processing specified in the display area DA1 to the second processing, and the interference fringe ST to be detected appears. Captured image 82 (for example, captured images 82b and 82c shown in FIG. 7) can be adopted. In this case, since the operator can move the frame of the determination region DR while viewing the interference fringe ST, the operator can set the determination region DR at an appropriate position. Further, in the display area DA5, a moving image may be displayed by continuously playing back a series of captured images 82 obtained by continuous imaging. In this case, various buttons for controlling display such as reproduction or stop may be prepared, and display control by the operator may be accepted. Thereby, the operator can appropriately set the conditions of the determination region DR while checking the appearance of the interference fringes ST.

  The display area DA6 is an area for receiving an input of a target film thickness. The target film thickness is a thickness of the liquid film W1 of the first processing liquid, which is a standard when starting the second processing. When the target film thickness is input, the timing determination unit 92 specifies an interference fringe ST that appears when the target film thickness corresponds to the target film thickness. For this specific processing, as a preliminary preparation, the thickness of the liquid film W1 is measured after the discharge of the processing liquid from the nozzle 30 in the first processing is stopped. A relationship between each appearance time when each interference fringe ST appears and the thickness of the liquid film W1 may be specified. In this case, the thickness of the liquid film W1 corresponding to the appearance timing of each interference fringe ST may be determined in each case where the first processing is performed while changing the conditions of the processing liquid, the discharge amount, and the rotation speed. . Note that the position of the substrate W at which the thickness is measured may be at the center of the substrate W, at the outer edge, or at an intermediate position between them.

  When the target film thickness is input in the display area DA6, in the display areas DA2 and DR3, according to the interference fringe ST corresponding to the target film thickness, a detection pattern and a position pattern candidate corresponding to the interference fringe ST May be narrowed down and displayed. In this case, the detection pattern and the position pattern may be determined in advance for each interference fringe ST to be detected.

  Further, depending on the conditions of the number of revolutions or the discharge time in the first process, the interference fringe ST to be detected may not be specified because the input target film thickness is not reached. In such a case, a display such as "not detectable, increase the step time" may be displayed. Thereby, the operator can be prompted to change the processing conditions.

<2. Second Embodiment>
Next, a second embodiment will be described. In the following description, elements having the same or similar functions as the elements already described will be denoted by the same reference numerals or reference signs obtained by adding alphabetic characters, and detailed description may be omitted.

  FIG. 13 is a diagram illustrating a substrate processing apparatus 100A according to the second embodiment. The control unit 9A of the substrate processing apparatus 100A includes a timing determination unit 92A. The timing determination unit 92A includes a feature vector extraction unit 922 and a classifier K2.

  The feature vector extraction unit 922 extracts a feature vector that is an array of a plurality of types of feature amounts from each of the series of captured images 82 acquired by the continuous imaging in step S22. The item of the feature amount is, for example, a sum of pixel values or luminance in a gray scale, a standard deviation of the pixel value or luminance, or the like.

  Based on the feature vector extracted by the feature vector extraction unit 922, the classifier K2 converts the captured image 82 into a first class indicating that the image is a guide for determining the second processing start timing, and a second processing start The image is classified into a second class indicating that the image does not serve as a guide for determining the timing.

  The timing determination unit 92A classifies a series of captured images 82 by the classifier K2. When the captured image 82 classified into the first class appears, the timing determination unit 92A determines the second processing start timing according to the time at which the captured image 82 was acquired. That is, the classifier K2 is an example of an image determination unit that determines whether or not a captured image is an image serving as a guide for determining the timing based on a plurality of types of feature vectors.

  As shown in FIG. 13, a communication unit 99 is connected to the control unit 9A. The communication unit 99 is provided for the control unit 9A to perform data communication with the server 8. The substrate processing apparatus 100, the communication unit 99, and the server 8 constitute a substrate processing system. The classifier K2 is generated by the server 8 by machine learning, and is provided from the server 8 to the control unit 9A via the communication unit 99.

  The server 8 includes a machine learning unit 80. The machine learning unit 80 generates a classifier K2 by machine learning. As the machine learning, known methods such as a neural network, a decision tree, a support vector machine (SVM), and discriminant analysis can be adopted.

  As the teacher data used for the machine learning of the machine learning unit 80, for example, data obtained by teaching a class to each of the captured images 82 (or their feature vectors) obtained by the camera 70 can be used. The captured image 82 acquired by the camera 70 can be provided from the substrate processing apparatus 100 to the server 8 via the communication unit 99.

  For example, when the captured images 82a to 82d illustrated in FIG. 7 are used as the teacher data, the captured image 82 serving as a guide of the second processing start timing includes the captured image 82c (that is, the number of the interference fringes ST appearing on the substrate W is smaller). (3 states), the first class indicating the start timing of the photographed image 82c is taught. Then, a second class indicating that the captured images 82a, 82b, and 82d are not a standard of the start timing may be taught. By preparing a large number of such teacher data and causing the machine learning unit 80 to learn, a classifier K2 that classifies the captured image 82 between the first and second classes based on the feature vector by the machine learning unit 80 is provided. Generate.

  The classifier K2 determines the type of the substrate W (for example, the size of the substrate W, the presence or absence of a structure such as a circuit pattern on the upper surface of the substrate W, the affinity of the upper surface of the substrate W with water (hydrophobic / hydrophilic)). Alternatively, a plurality of types of classifiers K2 may be generated for different conditions of the first process (type of processing liquid, discharge amount, discharge time). In this case, machine learning may be performed by preparing teacher data for each type of the substrate W or for different conditions of the first processing.

  By connecting a plurality of substrate processing apparatuses 100 to the server 8 so that they can communicate with each other, the server 8 may provide a classifier K2 to each of the substrate processing apparatuses 100.

  It is not essential that the classifier K2 be provided from the server 8. For example, the classifier K2 may be provided to the control unit 9 via a storage medium such as an optical medium and a flash memory. Further, when the substrate processing apparatus 100 includes the machine learning unit 80, the classifier K2 may be generated in the substrate processing apparatus 100.

  In the substrate processing apparatus 100A, in the second processing start timing determination processing, the timing determination unit 92A classifies a series of captured images 82 acquired by the camera 70 after step S24 (supply of IPA is stopped) shown in FIG. The detector K2 detects the captured image 82 as a guide of the second processing start timing by performing the class classification. Then, the timing determination unit 92A sets the detection time at which the captured image 82 was detected or the time obtained by adding a predetermined delay time to the detection time as the second processing start timing.

  In the present embodiment, the classifier K2 performs the class classification based on the entire captured image 82. Therefore, the entire captured image 82 is set as the determination area. Further, as described above, the classifier K2 is generated by machine learning using the captured image 82 in which the class is taught according to the appearance state of the interference fringe ST as teacher data. For this reason, the timing determination unit 92A determines the timing of the second processing in accordance with the interference fringe ST moving outward in the radial direction in the determination area (an extreme point regarding the light intensity on the captured image 82). Become.

  Also in the present embodiment, the second processing start timing can be determined based on the interference fringe ST that appears according to the thickness of the liquid film W1 of the first processing liquid. Therefore, when the second processing is liquid processing, the replacement with the second processing liquid can be promoted by starting the second processing after making the liquid film W1 as thin as possible, and thus the supply amount of the second processing liquid. And the supply time can be shortened. Further, even when the second processing is a drying processing, the drying processing can be started when the liquid film W1 of the first processing liquid has an optimum thickness.

  Note that it is not essential that the entire captured image 82 be teacher data. For example, only the image portion in the determination area DR from the captured image 82 can be used as teacher data. In this case, since the image size can be reduced, the amount of various processing operations can be reduced.

  Although the present invention has been described in detail, the above description is illustrative in all aspects and the present invention is not limited thereto. It is understood that innumerable modifications that are not illustrated can be assumed without departing from the scope of the present invention. The configurations described in the above embodiments and the modifications can be combined or omitted as long as they do not contradict each other.

Reference Signs List 100, 100A substrate processing apparatus 1 cleaning processing unit 8 server 9, 9A control unit 10 chamber 20 spin chuck 21 spin base 22 spin motor 24 rotation axis 26 chuck pin 30, 60, 65 nozzle 31 discharge head 70 camera 71 illumination unit 80 machine Learning unit 82, 82a, 82b, 82c, 82d Captured image 91 Judgment area setting unit 92, 92A Timing determination unit 96 Storage unit 97 Display unit 98 Input unit 99 Communication unit 921 Extreme value point detection unit 922 Feature vector extraction unit CX Rotation axis DR judgment area DR11, DR21-DR23, DR31 judgment area K2 classifier (image judgment unit)
ST, ST1-ST3, STL Interference fringes W Substrate W1 Liquid film (of first processing liquid)

Claims (17)

A substrate processing method for processing an upper surface of a substrate rotating in a horizontal posture with a processing liquid,
(A) holding the substrate in a horizontal position;
(B) rotating the substrate held in the horizontal posture in the step (a) around a vertical rotation axis;
(C) supplying a first processing liquid to the upper surface of the substrate rotated in the step (b);
(D) after the step (c), stopping the supply of the first processing liquid;
(E) after the step (d), a step of thinning the film of the first processing solution remaining on the upper surface of the substrate;
(F) in the step (e), photographing the upper surface of the substrate with a camera;
(G) in the determination region set in the captured image acquired in the step (f), the light intensity in the radial direction orthogonal to the rotation axis is maximized or minimized, and Determining a timing for performing the second processing;
(H) performing the second processing on the substrate according to the timing determined in the step (g);
And a substrate processing method. The substrate processing method according to claim 1, wherein
In the step (h), the second processing is started while the film of the first processing liquid remains on the entire upper surface of the substrate. The substrate processing method according to claim 1 or 2, wherein
The substrate processing method, wherein the determination region is set in the upper surface of the substrate. The substrate processing method according to claim 3, wherein
The step (g) includes:
(G1) determining the timing according to the time from when one extreme point is detected in the determination area to when the next extreme point is detected;
And a substrate processing method. The substrate processing method according to claim 4, wherein
The step (g) includes:
(G2) a first time from the detection of the first extreme point to the detection of the second extreme point, and a third extreme from the detection of the second extreme point, within the determination region. Determining the timing based on a second time until a value point is detected;
And a substrate processing method. The substrate processing method according to any one of claims 1 to 3, wherein
The step (g) includes:
(G3) determining the timing based on a first distance between the first extreme point detected in the determination area and a second extreme point radially inward from the first extreme point. The process of determining,
And a substrate processing method. The substrate processing method according to claim 6, wherein
The determination region includes a first determination region, and a second determination region that is radially inward from the first determination region,
The step (g) comprises:
(G4) determining the timing based on the first extreme point being detected in the first determination area and the second extreme point being detected in the second determination area. Substrate processing method. The substrate processing method according to claim 7, wherein
(I) before the step (g), changing a radial position of the second determination area with respect to the first determination area;
A substrate processing method, further comprising: The substrate processing method according to any one of claims 6 to 8, wherein
The step (g) includes:
(G5) the first distance and a second distance between the second extreme point and a third extreme point radially inward from the second extreme point in the determination area. Determining the timing based on
And a substrate processing method. The substrate processing method according to any one of claims 1 to 9, wherein
The step (g) includes:
(G6) determining the timing by detecting any of the three extreme points counted from the last detectable final extreme point in the plurality of extreme points in the determination area;
And a substrate processing method. The substrate processing method according to any one of claims 1 to 10, wherein
A substrate processing method, wherein the camera is an infrared camera. The substrate processing method according to claim 11, wherein
The step (f) includes:
(F1) irradiating the upper surface of the substrate with infrared light;
And a substrate processing method. The substrate processing method according to any one of claims 1 to 12, wherein
The substrate processing method, wherein the second processing is a processing of supplying a second processing liquid different from the first processing liquid to an upper surface of the substrate. The substrate processing method according to any one of claims 1 to 12, wherein
The substrate processing method, wherein the second process is a process of removing the first processing liquid remaining on the upper surface of the substrate by increasing the rotation speed of the substrate compared to the step (e). A substrate processing apparatus for processing a processing liquid on an upper surface of a substrate rotating in a horizontal posture,
A substrate holding unit for holding the substrate in a horizontal position,
A rotating unit that rotates a target substrate, which is a substrate held by the substrate holding unit, around a vertical rotation axis,
A first processing liquid supply unit configured to supply a first processing liquid to an upper surface of the target substrate;
A camera for photographing the upper surface of the target substrate,
In the determination region set in the captured image obtained by the camera, in accordance with the movement of the extreme point where the light intensity in the radial direction orthogonal to the rotation axis becomes the maximum value or the minimum value toward the radially outward direction. A timing determining unit that determines a timing of performing the second processing on the target substrate;
A second process execution unit that performs a second process on the target substrate according to the timing determined by the timing determination unit;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 15, wherein
The substrate processing apparatus, wherein the determination area is set in the upper surface of the target substrate. The substrate processing apparatus according to claim 15 or 16, wherein
The timing determining unit includes:
A feature vector extraction unit that extracts a plurality of types of feature vectors from the captured image,
Based on the plurality of types of feature vectors, an image determination unit that determines whether the captured image is an image that is a guide for determining the timing,
And a substrate processing apparatus.