JP7202106B2 - Substrate processing method and substrate processing apparatus - Google Patents

Description

The present invention relates to technology for processing a substrate, and more particularly to technology for processing a substrate with a processing liquid. Substrates to be processed include, for example, semiconductor substrates, FPD (Flat Panel Display) substrates such as liquid crystal display devices and organic EL (Electroluminescence) display devices, optical disk substrates, magnetic disk substrates, magneto-optical disk substrates, Photomask substrates, ceramic substrates, solar cell substrates, printed circuit boards, etc. are included.

In the manufacture of semiconductors, there are cases in which a semiconductor substrate is subjected to a second treatment after a first treatment of treating the surface of the semiconductor substrate with a predetermined liquid. For example, Patent Document 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, the semiconductor substrate is treated with a liquid PGMEA (propylene glycol monomethyl ether acetate) first, and then treated with a hydrophobizing agent.

Further, Japanese Patent Application Laid-Open No. 2002-200002 discloses a technique for suppressing collapse of a resist pattern during drying of a substrate by high-speed rotation. Specifically, a substrate on which a resist pattern is formed is first subjected to a liquid treatment of supplying a rinsing liquid as a first treatment, and then a drying treatment of rotating the substrate at high speed to dry it as a second treatment. done. Patent Document 2 discloses controlling the rotation speed of the substrate according to the spread of the dry area on the main surface of the substrate from the center to the outer periphery after the supply of the rinse liquid, and furthermore, controlling the boundary of the dry area. position is detected by measuring changes in interference fringes.

JP 2010-114414 A JP-A-2004-335542

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 Document 1, PGMEA is supplied to the substrate in the first treatment, and after the supply is stopped, the substrate is supplied with a hydrophobizing agent, which is the second treatment. At this time, if the PGMEA liquid film on the substrate is excessively thick, the substitution efficiency with the hydrophobizing agent decreases. However, Patent Document 1 does not disclose any technique for supplying the hydrophobizing agent at the optimum timing.

Moreover, Patent Document 2 only describes that the control for starting the drying process of the second process is performed by measuring a change in the interference fringes, and does not disclose any technique for detecting the interference fringes. Therefore, it is difficult to appropriately determine the timing of starting the drying process based on Cited Document 2.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a technique for appropriately determining the timing of starting a subsequent second process after a first process, which is a liquid process.

In order to solve the above-described problems, a substrate processing method of a first aspect is a substrate processing method for processing the upper surface of a substrate rotating in a horizontal posture with a processing liquid, comprising: (a) holding the substrate in the horizontal posture; (b) rotating the substrate held in a horizontal posture in step (a) around a vertical rotation axis; (d) stopping the supply of the first processing liquid after step (c); (f) photographing the upper surface of the substrate with a camera in the step (e); and (g) the photographed image obtained in the step (f). In the determination region set on the upper surface of the substrate, the extreme point at which the light intensity in the radial direction perpendicular to the rotation axis is maximum or minimum is moved radially outward . (h) performing the second process on the substrate in accordance with the timing determined in the step (g); (g1) determining the timing when the time difference between the detection of one extremum point and the detection of the next extremum point in the determination region corresponds to a preset detection time difference; process .
A substrate processing method of a second aspect is the substrate processing method of the first aspect, wherein the step (g) includes (g2) detecting a second extreme point in the determination region after the first extreme point is detected. A first time, which is the time difference until the point is detected, and a second time, which is the time difference between the detection of the second extreme point and the detection of the third extreme point, are set in advance. determining the timing when corresponding to the detected time difference.
A substrate processing method according to a third aspect is a substrate processing method in which the upper surface of a substrate that rotates in a horizontal position is processed with a processing liquid, comprising: (a) holding the substrate in a horizontal position; ) rotating the substrate held in a horizontal position around a vertical rotation axis; (d) stopping the supply of the first processing liquid after the step (c); and (e) removing the film of the first processing liquid remaining on the upper surface of the substrate after the step (d). (f) photographing the upper surface of the substrate with a camera in the step (e); The timing of performing the second processing on the substrate is determined according to the radially outward movement of the extreme value point at which the light intensity in the radial direction perpendicular to the rotation axis is maximum or minimum within the determination region. and (h) performing the second process on the substrate according to the timing determined in the step (g), wherein the step (g) includes (g3) the determination region When a first distance between a first extreme point detected in and a second extreme point radially outwardly away from the first extreme point corresponds to a preset distance between extreme points B., determining the timing.
The substrate processing method of the fourth aspect is the substrate processing method of the third aspect, wherein the step (g) includes (g5) the first distance and the second extreme point and the determining the timing when a second distance between the second extreme point and a third extreme point radially outwardly away corresponds to a preset inter-extreme point distance; including.
A substrate processing method according to a fifth aspect is a substrate processing method in which the upper surface of a substrate that rotates in a horizontal position is processed with a processing liquid, comprising: (a) holding the substrate in a horizontal position; ) rotating the substrate held in a horizontal position around a vertical rotation axis; (d) stopping the supply of the first processing liquid after the step (c); and (e) removing the film of the first processing liquid remaining on the upper surface of the substrate after the step (d). (f) photographing the upper surface of the substrate with a camera in the step (e); The timing of performing the second processing on the substrate is determined according to the radially outward movement of the extreme value point at which the light intensity in the radial direction perpendicular to the rotation axis is maximum or minimum within the determination region. and (h) performing the second process on the substrate according to the timing determined in the step (g), wherein the determination areas are a first determination area and the second determination area. and a second determination region radially outwardly away from the first determination region, wherein the step (g) comprises (g4) detecting a first extreme point detected in the first determination region and the second determination region; determining the timing based on simultaneous detection of a second extreme point detected in .
A substrate processing method according to a sixth aspect is the substrate processing method according to the fifth aspect, wherein the determination regions include the first determination region, the second determination region, and a substrate radially outward from the second determination region. a distant third determination region, wherein step (g4) includes detecting the first extreme point in the first determination region and detecting the second extreme point in the second determination region; and determining the timing based on simultaneously detecting a third extremum point in the third determination region.
A substrate processing method of a seventh aspect is the substrate processing method of the fifth aspect or the sixth aspect, wherein (i) the diameter of the second determination region with respect to the first determination region is determined before the step (g). Further comprising changing the relative position in the direction.
A substrate processing method according to an eighth aspect is a substrate processing method in which the upper surface of a substrate rotating in a horizontal position is processed with a processing liquid, comprising: (a) holding the substrate in a horizontal position; ) rotating the substrate held in a horizontal position around a vertical rotation axis; (d) stopping the supply of the first processing liquid after the step (c); and (e) removing the film of the first processing liquid remaining on the upper surface of the substrate after the step (d). (f) photographing the upper surface of the substrate with a camera in the step (e); The timing of performing the second processing on the substrate is determined according to the radially outward movement of the extreme value point at which the light intensity in the radial direction perpendicular to the rotation axis is maximum or minimum within the determination region. and (h) performing the second process on the substrate according to the timing determined in the step (g), wherein the step (g) includes (g6) the determination region and setting the time obtained by adding a predetermined delay time to the time at which the last extreme point among the plurality of extreme points is detected as the timing.

A substrate processing method of a ninth aspect is the substrate processing method of any one of the first to eighth aspects , wherein in the step (h), the entire upper surface of the substrate is coated with the first processing liquid. While the film remains, the second process is started.

A substrate processing method of a tenth aspect is the substrate processing method of any one of the first to ninth aspects, wherein the camera is an infrared camera.

A substrate processing method according to an eleventh aspect is the substrate processing method according to any one of the first to tenth aspects, wherein the second treatment comprises applying a second treatment liquid different from the first treatment liquid to the upper surface of the substrate. 2 is a process of supplying a processing liquid.

A substrate processing method according to a twelfth aspect is the substrate processing method according to any one of the first to tenth aspects, wherein the second processing comprises rotating the substrate at a speed 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 by enlarging it.

A substrate processing apparatus according to a thirteenth aspect is a substrate processing apparatus that performs liquid processing on the upper surface of a substrate that rotates in a horizontal position, and includes a substrate holding part that holds the substrate in the horizontal position, and a substrate held by the substrate holding part. a rotation unit for rotating a target substrate around a vertical rotation axis, a first processing liquid supply unit for supplying a first processing liquid to the upper surface of the target substrate, a camera for photographing the upper surface of the target substrate; A radial direction of an extreme point at which the light intensity in a radial direction orthogonal to the rotation axis becomes a maximum value or a minimum value within the determination area set on the upper surface of the target substrate in the photographed image acquired by the camera. a timing determination unit that determines timing for performing the second processing on the target substrate according to the outward movement, and performing the second processing on the target substrate according to the timing determined by the timing determination unit. and a second processing execution unit for determining the timing, wherein the timing determination unit determines a preset detection time difference from when one extreme point is detected to when the next extreme point is detected in the determination area. The timing is determined when corresponding to .
A substrate processing apparatus according to a fourteenth aspect is the substrate processing apparatus according to the thirteenth aspect, wherein the timing determination unit detects the second extreme point after the first extreme point is detected in the determination region. A first time, which is the time difference until the detection of the second extreme point, and a second time, which is the time difference between the detection of the second extreme point and the detection of the third extreme point, correspond to preset detection time differences. to determine the timing.
A substrate processing apparatus according to a fifteenth aspect is a substrate processing apparatus that performs liquid processing on the upper surface of a substrate that rotates in a horizontal position, and includes a substrate holding part that holds the substrate in the horizontal position, and a substrate held by the substrate holding part. a rotation unit for rotating a target substrate around a vertical rotation axis, a first processing liquid supply unit for supplying a first processing liquid to the upper surface of the target substrate, a camera for photographing the upper surface of the target substrate; Within the determination area set on the upper surface of the target substrate in the photographed image acquired by the camera, the light intensity in the radial direction orthogonal to the rotation axis line is outside the extreme value point at which the light intensity has a maximum value or a minimum value in the radial direction. a timing determination unit that determines timing for performing the second processing on the target substrate according to the movement toward the target substrate, and performing the second processing on the target substrate according to the timing determined by the timing determination unit. a second processing execution unit, wherein the timing determination unit is positioned between a first extreme point detected in the determination region and a second extreme point radially outwardly away from the first extreme point; The timing is determined when the first distance of corresponds to a preset distance between extreme points.
A substrate processing apparatus according to a sixteenth aspect is the substrate processing apparatus according to the fifteenth aspect, wherein the timing determining unit determines the second extreme point and the second extreme value within the first distance and the determination region. The timing is determined when a second distance between the point and a third extreme point radially outwardly away from the point corresponds to a preset inter-extreme point distance.
A substrate processing apparatus according to a seventeenth aspect is a substrate processing apparatus that performs liquid processing on an upper surface of a substrate that rotates in a horizontal position, comprising: a substrate holding part that holds the substrate in the horizontal position; and a substrate held by the substrate holding part. a rotation unit for rotating a target substrate around a vertical rotation axis, a first processing liquid supply unit for supplying a first processing liquid to the upper surface of the target substrate, a camera for photographing the upper surface of the target substrate; Within the determination area set on the upper surface of the target substrate in the photographed image acquired by the camera, the light intensity in the radial direction orthogonal to the rotation axis line is outside the extreme value point at which the light intensity has a maximum value or a minimum value in the radial direction. a timing determination unit that determines timing for performing the second processing on the target substrate according to the movement toward the target substrate, and performing the second processing on the target substrate according to the timing determined by the timing determination unit. a second processing execution unit, wherein the determination region includes a first determination region and a second determination region radially outwardly spaced apart from the first determination region; The timing is determined based on simultaneous detection of the first extreme point detected in the first determination area and the second extreme point detected in the second determination area.
A substrate processing apparatus according to an eighteenth aspect is the substrate processing apparatus according to the seventeenth aspect, wherein the determination regions include the first determination region, the second determination region, and a substrate radially outward from the second determination region. and a distant third determination region, wherein the timing determination unit detects the first extreme point in the first determination region, detects the second extreme point in the second determination region, and The timing is determined based on the fact that the detection of the third extreme value point in the third determination region and the detection of the third extremum point are performed simultaneously.
A substrate processing apparatus according to a nineteenth aspect is the substrate processing apparatus according to the seventeenth aspect or the eighteenth aspect, wherein the timing determining section determines the second determination area relative to the first determination area before determining the timing. Change the relative position in the radial direction.
A substrate processing apparatus according to a twentieth aspect is a substrate processing apparatus that performs liquid processing on the upper surface of a substrate that rotates in a horizontal position, comprising: a substrate holding part that holds the substrate in the horizontal position; and a substrate held by the substrate holding part. a rotation unit for rotating a target substrate around a vertical rotation axis, a first processing liquid supply unit for supplying a first processing liquid to the upper surface of the target substrate, a camera for photographing the upper surface of the target substrate; Within the determination area set on the upper surface of the target substrate in the photographed image acquired by the camera, the light intensity in the radial direction orthogonal to the rotation axis line is outside the extreme value point at which the light intensity has a maximum value or a minimum value in the radial direction. a timing determination unit that determines timing for performing the second processing on the target substrate according to the movement toward the target substrate, and performing the second processing on the target substrate according to the timing determined by the timing determination unit. and a second processing execution unit, wherein the timing determination unit determines a time obtained by adding a predetermined delay time to the time when the extreme point that appears last among the plurality of extreme points is detected in the determination region. , the above timing.
A substrate processing apparatus according to a twenty-first aspect is the substrate processing apparatus according to any one of the thirteenth to twentieth aspects, wherein the second processing execution unit applies the first processing liquid to the entire upper surface of the target substrate. The second process is started while the film of .
A substrate processing apparatus according to a twenty-second aspect is the substrate processing apparatus according to any one of the thirteenth to twenty-first aspects, wherein the camera is an infrared camera.
A substrate processing apparatus according to a twenty-third aspect is the substrate processing apparatus according to any one of the thirteenth to twenty-second aspects, wherein the second treatment is performed on the upper surface of the target substrate with a liquid different from the first treatment liquid. This is the process of supplying the second processing liquid.
A substrate processing apparatus according to a twenty-fourth aspect is the substrate processing apparatus according to any one of the thirteenth to twenty-second aspects, wherein the second processing increases the rotational speed of the rotating portion to increase the rotation speed of the target substrate. This is a process for removing the first processing liquid remaining on the upper surface of the .

In any of the first, third, fifth, and eighth aspects of the substrate processing method , when the supply of the first processing liquid is stopped, the rotation of the substrate causes the first processing liquid to flow. By being shaken off, the thickness of the liquid film is gradually reduced. At this time, interference fringes are generated that move radially outward according to the thickness of the liquid film. The interference fringes correspond to extreme points of light intensity. 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 the timing when the liquid film of the first processing liquid has an optimum thickness.

According to the substrate processing method of the ninth aspect, the second processing is started while the first processing liquid remains on the entire upper surface of the substrate. Therefore, it is possible to suppress the progress of local drying of the substrate.

In any one of the first , third, fifth, and eighth aspects of the substrate processing method , a determination region is set on the upper surface of the substrate in the photographed image. As a result, it is possible to improve the detection accuracy of extreme points corresponding to interference fringes generated on the upper surface of the substrate.

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

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

According to the substrate processing method of the third aspect, by calculating the first distance, it is possible to determine whether or not the interference fringes to be detected have appeared.

According to the substrate processing method of the fifth aspect, by setting the first and second determination regions separated by an appropriate distance in the radial direction and detecting the interference fringes in these determination regions, the interference fringes of the inspection target are can be determined whether appears.

According to the substrate processing method of the seventh aspect, the relative position of the second determination area with respect to the first determination area can be changed in the radial direction. As a result, the first extreme point and the second extreme point, which serve as indicators for determining the timing of the second process, can be detected simultaneously in the first determination area and the second determination area, for example.

According to the substrate processing method of the fourth aspect, by acquiring the first distance and the second distance, it is possible to determine whether or not the interference fringes to be detected have appeared.

According to the substrate processing method of the eighth aspect, the timing of performing the second processing can be determined 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 tenth aspect, the light intensity corresponding to the interference fringes can be appropriately detected by detecting infrared rays.

According to the substrate processing method of the eleventh aspect, the second processing liquid can be supplied when the first processing liquid reaches the target thickness. Therefore, since the first treatment liquid can be quickly replaced with the second treatment liquid, the amount of the second treatment liquid used can be reduced.

According to the substrate processing method of the twelfth aspect, the rotational speed of the substrate is increased when the first processing liquid reaches the target thickness. It is possible to prevent uneven processing of the substrate due to a large amount of remaining first processing liquid.

In any one of the thirteenth , fifteenth, seventeenth and twentieth aspects of the substrate processing apparatus , when the supply of the first processing liquid is stopped, the rotation of the substrate causes the first processing liquid to flow. By being shaken off, the thickness of the liquid film is gradually reduced. At this time, interference fringes are generated that move radially outward according to the thickness of the liquid film. The interference fringes correspond to extreme points of light intensity. 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 the timing when the liquid film of the first processing liquid has an optimum thickness.

Any of the thirteenth , fifteenth, seventeenth and twentieth aspects of the substrate processing apparatus can detect interference fringes appearing on the substrate.

It is a figure which shows the whole structure of the substrate processing apparatus 100 of 1st Embodiment. 1 is a schematic plan view of a cleaning unit 1 of a first embodiment; FIG. 1 is a schematic longitudinal sectional view of a cleaning unit 1 of a first embodiment; FIG. It is a figure which shows the positional relationship between the camera 70 and the nozzle 30 which is a movable part. 3 is a block diagram of camera 70 and control unit 9. FIG. 3 is a diagram showing an example of the flow of substrate processing in one cleaning processing unit 1 of the substrate processing apparatus 100. FIG. FIG. 8 is a diagram showing captured images 82a to 82d at each timing during transition from the first process to the second process; FIG. 4 is a diagram showing a first detection pattern of interference fringes ST; FIG. 10 is a diagram showing a second detection pattern of interference fringes ST; FIG. 10 is a diagram showing a third detection pattern of interference fringes ST; FIG. 10 is a diagram showing a flow of processing for determining second processing start timing; FIG. 10 is a view showing a setting screen SW1 for setting conditions for detecting interference fringes ST; It is a figure which shows 100 A of substrate processing apparatuses of 2nd Embodiment.

Embodiments of the present invention will be described below with reference to the accompanying drawings. It should be noted that the constituent elements described in this embodiment are merely examples, and are not intended to limit the scope of the present invention only to them. In the drawings, for ease of understanding, the dimensions and numbers of each part may be exaggerated or simplified as necessary.

Expressions indicating relative or absolute positional relationships (e.g., "in one direction", "along one direction", "parallel", "perpendicular", "center", "concentric", "coaxial", etc.) are used unless otherwise specified. Not only the positional relationship is strictly expressed, but also the relatively displaced state in terms of angle or distance within the range of tolerance or equivalent function. Expressions indicating equality (e.g., "identical", "equal", "homogeneous", etc.), unless otherwise specified, not only express quantitatively strictly equality, but also have tolerances or equivalent functions It shall also represent the state in which there is a difference. Expressions indicating shapes (e.g., "square shape" or "cylindrical shape"), unless otherwise specified, not only represent the shape strictly geometrically, but also to the extent that the same degree of effect can be obtained, such as Shapes having unevenness, chamfering, etc. are also represented. The terms "comprise", "comprise", "comprise", "include" or "have" one element are not exclusive expressions that exclude the presence of other elements. Unless otherwise specified, "on" includes not only the case where two elements are in contact but also the case where two elements are separated.

<1. First Embodiment>
FIG. 1 is a diagram showing the 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 using a chemical solution and a rinse liquid such as pure water on a substrate W, which is a circular thin plate-shaped silicon substrate, and then performs a drying process. Examples of chemical solutions include SC1 (ammonia-hydrogen peroxide mixture), SC2 (hydrochloric hydrogen peroxide mixed water solution), DHF solution (dilute hydrofluoric acid), and the like. be done. In the following description, the chemical liquid and the rinse liquid may be collectively referred to as "processing liquid". Note that the substrate processing apparatus 100 supplies a coating liquid such as a photoresist liquid for film formation processing, a chemical liquid for removing unnecessary films, and a chemical liquid for etching, instead of cleaning processing, to wet-process the substrate. may be configured to

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

The indexer 102 transports into the apparatus a substrate W to be processed that has been received from outside the apparatus, and unloads a processed substrate W that has been subjected to the cleaning process to the outside of the apparatus. The indexer 102 has a plurality of carriers (not shown) and a transfer robot (not shown). As the carrier, a FOUP (Front Opening Unified Pod) or a SMIF (Standard Mechanical InterFace) pod that stores the substrate W in a closed space, or an OC (Open Cassette) that exposes the substrate W to the outside air may be employed. The transfer robot transfers substrates W between the carrier and main transfer robot 103 .

The cleaning processing unit 1 performs liquid processing and drying processing on one substrate W. As shown in FIG. Twelve cleaning units 1 are arranged in the substrate processing apparatus 100 . Specifically, four towers each including three vertically stacked cleaning units 1 are arranged 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 twelve, and may be changed as appropriate.

The main transfer robot 103 is installed in the center of four towers in which the cleaning processing units 1 are stacked. The main transfer robot 103 carries the substrate W to be processed received from the indexer 102 into each cleaning processing unit 1 . Further, the main transport robot 103 carries out the processed substrate W from each cleaning processing unit 1 and passes it to the indexer 102 .

<Washing unit 1>
One of the twelve cleaning units 1 mounted on the substrate processing apparatus 100 will be described below. , have the same configuration.

FIG. 2 is a schematic plan view of the cleaning unit 1 of the first embodiment. FIG. 3 is a schematic longitudinal sectional view of the cleaning unit 1 of the first embodiment. 2 shows a state in which the spin chuck 20 does not hold the substrate W, and FIG. 3 shows a state in which the spin chuck 20 holds the substrate W. As shown in FIG.

The cleaning processing unit 1 includes a spin chuck 20 that holds the substrate W in a horizontal posture (a posture in which the normal to the surface of the substrate W is in the vertical direction), and the upper surface of the substrate W held by the spin chuck 20 . a processing cup 40 surrounding 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 partition the inner space of the chamber 10 into upper and lower parts.

The chamber 10 includes side walls 11 that extend vertically and surround the four sides, a ceiling wall 12 that closes the upper side of the side walls 11 , and a floor wall 13 that closes the lower side of the side walls 11 . A space surrounded by the side walls 11, the ceiling wall 12, and the floor wall 13 serves as a processing space for the substrates W. As shown in FIG. Further, a part of the side wall 11 of the chamber 10 is provided with a loading/unloading port for loading/unloading the substrate W by the main transfer robot 103 into/from the chamber 10 and a shutter for opening/closing the loading/unloading port (both not shown). ing.

A fan filter unit (FFU) 14 is attached to the ceiling wall 12 of the chamber 10 to further purify the air in the clean room in which the substrate processing apparatus 100 is installed and supply it to the processing space in the chamber 10 . . The FFU 14 is equipped with a fan and a filter (eg, HEPA filter) for taking air in the clean room and sending it out into the chamber 10 . FFU 14 creates a downflow of clean air in the processing space within chamber 10 . In order to uniformly disperse the clean air supplied from the FFU 14 , a punching plate with a large number of blowout holes may be provided directly below the ceiling wall 12 .

The spin chuck 20 has a spin base 21 , a spin motor 22 , a cover member 23 and a rotating shaft 24 . The spin base 21 has a disk shape and is fixed in a horizontal posture to the 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 rotating shaft 24 . The spin motor 22 rotates the spin base 21 in the horizontal plane via the rotation shaft 24 . Cover member 23 has a tubular shape surrounding spin motor 22 and rotating shaft 24 .

The outer diameter of the disk-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 this embodiment) chuck pins 26 are erected on the periphery of the holding surface 21 a of the spin base 21 . Each chuck pin 26 is arranged at equal intervals along the circumference corresponding to the outline of the outer circumference of the circular substrate W. As shown in FIG. In this embodiment, four chuck pins 26 are provided at intervals of 90°. Each chuck pin 26 is driven in conjunction with a link mechanism (not shown) housed in the spin base 21 . The spin chuck 20 grips the substrate W with each of the chuck pins 26 in contact with the outer peripheral edge of the substrate W, thereby holding the substrate W above the spin base 21 in a horizontal position close to the holding surface 21a. Hold (see FIG. 3). Further, the spin chuck 20 releases the grip of the substrate W by separating each of the chuck pins 26 from the outer peripheral edge of the substrate W. As shown in FIG. Each chuck pin 26 is a substrate holder that holds the substrate W in a horizontal posture.

A cover member 23 covering 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 the upper end of the cover member 23, a brim-shaped member 25 is provided that projects substantially horizontally outward from the cover member 23 and further bends and extends downward. In a state where the spin chuck 20 holds the substrate W by gripping it with a plurality of chuck pins 26, the spin motor 22 rotates the rotation shaft 24, thereby rotating the rotation axis CX along the vertical direction passing through the center of the substrate W. The substrate W can be rotated. Note that the drive of the spin motor 22 is controlled by the control section 9 . In the following description, the horizontal direction orthogonal to the rotation axis CX is called "radial direction". In addition, the radial direction toward the rotation axis CX is referred to as "radially inward", and the radial direction away from the rotation axis CX is referred to as "radial outward".

The nozzle 30 is configured by attaching an ejection head 31 to the tip of a nozzle arm 32 . The base end side of the nozzle arm 32 is fixedly connected to the nozzle base 33 . A motor 332 (nozzle moving unit, see FIG. 4) provided on the nozzle base 33 can rotate about an axis extending in the vertical direction.

By rotating the nozzle base 33, the nozzle 30 moves horizontally 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. is moved in an arc along the The rotation of the nozzle base 33 swings the nozzle 30 above the holding surface 21 a of the spin base 21 . Specifically, above the spin base 21, it moves to a predetermined processing position TP1 extending in the horizontal direction. Note that moving the nozzle 30 to the processing position TP1 is the same as moving the ejection head 31 at the tip of the nozzle 30 to the processing position TP1.

The nozzles 30 are configured to be supplied with a plurality of types of processing liquids (including at least pure water), and the plurality of types of processing liquids can be discharged from the discharge head 31 . A plurality of ejection heads 31 may be provided at the tip of the nozzle 30, and the same or different treatment liquid may be ejected individually from each of them. The nozzle 30 (more specifically, the ejection head 31) stops at the processing position TP1 and ejects 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, 65 of this 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 tip of a nozzle arm 62, and a nozzle base 63 connected to the base end side of the nozzle arm 62 moves upward 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. A nozzle base 68 connected to the base end of the nozzle arm 67 moves the nozzle 65 to a processing position above the spin chuck 20 as indicated by an arrow AR69. and a standby position outside the processing cup 40 in an arc.

The nozzles 60 and 65 are also configured to supply a plurality of kinds of processing liquids including at least pure water, and discharge the processing liquids 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 with a pressurized gas to generate droplets, and injects a mixed fluid of the droplets and the gas onto the substrate W. may be Also, the number of nozzles provided in the cleaning unit 1 is not limited to three, and may be one or more.

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

The nozzle 30 is used for various types of rinse liquids, such as pure water (DIW), IPA (Isopropyl Alcohol), a water repellent agent such as a silylating agent, and DHF (Dilute HF: a mixture of hydrofluoric acid and pure water). It is connected to a processing liquid supply source, and various processing liquids can be separately discharged from an ejection head 31 at the tip of the nozzle 30 . 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 treatment liquid. Also, the nozzles 60 and 65 may eject some of the various treatment liquids.

A lower surface treatment liquid nozzle 28 is provided along the vertical direction so as to pass through the inner side of the rotating shaft 24 . An upper end opening of the lower surface 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 be supplied with a plurality of processing liquids. The processing liquid discharged from the lower surface processing liquid nozzle 28 lands on the lower surface of the substrate W held by the spin chuck 20 .

A processing cup 40 surrounding the spin chuck 20 includes an inner cup 41, a middle cup 42 and an outer cup 43 which can be raised and lowered independently of each other. The inner cup 41 surrounds the spin chuck 20 and has a shape substantially rotationally symmetrical with respect to the 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. A first guide portion 47 that rises from between the portion 45 and the outer wall portion 46 and extends obliquely upward toward the center (direction approaching the rotation axis CX of the substrate W held by the spin chuck 20) while drawing a smooth circular arc at its upper end. and a cylindrical inner wall portion 48 rising upward from between the first guide portion 47 and the outer wall portion 46 .

The inner wall portion 45 is housed with an appropriate gap maintained between the cover member 23 and the brim-shaped member 25 in the state in which the inner cup 41 is raised to the maximum. The intermediate wall portion 48 is housed with an appropriate gap maintained between a second guide portion 52 of the intermediate cup 42 and the processing liquid separation wall 53, which will be described later, in a state in which the inner cup 41 and the intermediate cup 42 are closest to each other. be.

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. A waste groove 49 is provided between the inner wall portion 45 and the first guide portion 47 for collecting and discarding the used treatment liquid. Between the first guide portion 47 and the inner wall portion 48 is an annular inner recovery groove 50 for collecting and recovering the used processing liquid. Further, between the inner wall portion 48 and the outer wall portion 46 is an annular outer recovery groove 51 for collecting and recovering a processing liquid different in kind from the inner recovery groove 50 .

The disposal groove 49 is connected to an exhaust liquid mechanism (not shown) for discharging the processing liquid collected in the disposal groove 49 and forcibly exhausting the inside of the disposal groove 49 . For example, four exhaust liquid mechanisms are provided at regular intervals along the circumferential direction of the disposal groove 49 . In the inner recovery groove 50 and the outer recovery groove 51, a recovery mechanism for recovering the processing liquid collected in the inner recovery groove 50 and the outer recovery groove 51 respectively to a recovery tank provided outside the substrate processing apparatus 100 is provided. (not shown) are connected. The bottoms of the inner recovery groove 50 and the outer recovery groove 51 are inclined by a slight angle with respect to the horizontal direction, and the recovery mechanism is connected to the lowest position. As a result, the processing liquid that has flowed into the inner recovery groove 50 and the outer recovery groove 51 is smoothly recovered.

The middle cup 42 surrounds the spin chuck 20 and has a shape substantially rotationally symmetrical with respect to the 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 .

Outside the first guide portion 47 of the inner cup 41, the second guide portion 52 draws a smooth circular arc from the lower end portion 52a coaxial with the lower end portion of the first guide portion 47 and the upper end of the lower end portion 52a. It has an upper end portion 52b extending obliquely upward toward the center side (direction approaching the rotation axis CX of the substrate W), and a folded portion 52c formed by folding the tip 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 maintained 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. Further, the upper end portion 52b is provided so as to overlap the upper end portion 47b of the first guide portion 47 of the inner cup 41 in the vertical direction. is close to the upper end portion 47b of the . When the inner cup 41 and the middle cup 42 are closest to each other, the folded portion 52c horizontally overlaps the tip of the upper end portion 47b of the first guide portion 47 .

The upper end portion 52b of the second guide portion 52 is formed so as to be thicker toward the bottom. The processing liquid separation wall 53 has a cylindrical shape extending downward from the lower outer peripheral edge of the upper end portion 52b. The processing liquid separation wall 53 is accommodated in the outer recovery groove 51 with an appropriate gap maintained between the inner wall portion 48 and the outer cup 43 in a state in which the inner cup 41 and the inner cup 42 are closest to each other.

The outer cup 43 has a shape substantially rotationally symmetrical with respect to the 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 inner cup 42 . This outer cup 43 has a function as a third guide portion. The outer cup 43 has a lower end portion 43a forming a cylindrical shape coaxial with the lower end portion 52a of the second guide portion 52, and a center side (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 the tip portion 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 maintains an appropriate gap between the processing liquid separation wall 53 of the inner cup 42 and the outer wall portion 46 of the inner cup 41 to form an outer recovery groove. Housed within 51. The upper end portion 43b is provided so as to overlap the second guide portion 52 of the middle cup 42 in the vertical direction. Keep a very small distance and get close to each other. When the inner 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 provided with an elevating mechanism (not shown) so that the inner cup 41, the middle cup 42 and the outer cup 43 can be lifted and lowered independently. be done. As such an elevating mechanism, various known mechanisms such as a ball screw mechanism and an air cylinder can be employed.

The partition plate 15 is provided around the processing cup 40 so as to vertically partition the inner space of the chamber 10 . The partition plate 15 may be a single plate-like member surrounding the processing cup 40, or may be a plurality of plate-like members joined together. Further, the partition plate 15 may have a through hole or a notch that penetrates in the thickness direction. A through hole is formed for passing the support shaft of.

The outer peripheral edge of the partition plate 15 is connected to the side wall 11 of the chamber 10 . Further, the edge portion of the partition plate 15 surrounding the processing cup 40 is formed in a circular shape with a diameter larger than the outer diameter of the outer cup 43 . Therefore, the partition plate 15 does not hinder the lifting of the outer cup 43 .

Also, an exhaust duct 18 is provided in the vicinity of the floor wall 13 at a portion of the side wall 11 of the chamber 10 . The exhaust duct 18 is communicatively connected to an exhaust mechanism (not shown). Of the clean air supplied from the fan filter unit 14 and flowing down inside the chamber 10 , the air that has passed 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 showing the positional relationship between the camera 70 and the nozzle 30 that is the movable part. The camera 70 is provided above the substrate W in the vertical direction. The camera 70 includes, for example, a CCD, which is one of solid-state imaging devices, an electronic shutter, and an optical system such as 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 (or its vicinity) of the upper surface of the substrate W in order to image the upper surface of the substrate W. Camera 70 includes in its field of view the entire top surface of substrate W held by spin chuck 20 . For example, in the horizontal direction, the field of view of the camera 70 includes the range enclosed by the dashed lines in FIG.

The camera 70 is installed at a position that includes at least the tip of the nozzle 30 at the processing position TP1, that is, includes the vicinity of the ejection head 31 in its imaging field of view. In this embodiment, as shown in FIG. 4, a camera 70 is installed at a position for capturing an image of the nozzle 30 at the processing position TP1 from above and in front. Therefore, the camera 70 can image an imaging area including the tip of the nozzle 30 at the processing position TP1. Similarly, the camera 70 takes an image of an imaging region including each tip when the nozzles 60 and 65 are in the processing positions when processing the substrate W held by the spin chuck 20 . When the camera 70 is installed at the position shown in FIGS. 2 and 4, the nozzles 30, 60 move laterally within the field of view of the camera 70, so that the tip of each nozzle 30, 60 at each processing position However, since the nozzle 65 moves in the depth direction within the field of view of the camera 70, there is a possibility that the movement in the vicinity of the processing position cannot be properly captured. In this case, a camera for imaging the nozzle 65 may be provided separately from the camera 70 .

By driving the nozzle base 33, the nozzle 30 is moved to 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 waiting position (the position indicated by the broken line in FIG. solid line position). The processing position TP1 is a position where a processing liquid is discharged from the nozzle 30 onto the upper surface of the substrate W held by the spin chuck 20 to perform cleaning processing. The processing position TP1 is a position near the center (rotational axis CX) of the substrate W held by the spin chuck 20 . The standby position is a position where the nozzles 30 stop discharging the treatment liquid and wait when the cleaning process is not performed. The standby position is a position away from above the spin base 21 and outside the processing cup 40 in the horizontal plane. A standby pod that accommodates the ejection head 31 of the nozzle 30 may be provided at the standby position.

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 may be a position away from the substrate W (that is, a position that does not overlap the substrate W in the vertical direction). state position). In the latter case, the treatment liquid ejected from the nozzles 30 may be scattered on the upper surface of the substrate W from the outside of the substrate W. As shown in FIG. Further, it is not essential to eject the processing liquid from the nozzles 30 while the nozzles 30 are stopped at the processing position TP1. For example, the nozzle 30 may be moved within a predetermined processing section extending horizontally above the substrate W with the processing position TP1 as one end while ejecting the processing liquid from the nozzle 30 .

As shown in FIG. 3 , an illumination unit 71 is provided inside the chamber 10 at a position above the partition plate 15 . The lighting 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. If 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, and 65 with light when the camera 70 takes an image. The illumination unit 71 emits visible light as illumination light. However, illumination light is not limited to visible light. As illumination light, for example, infrared rays with a wavelength of approximately 0.7 μm to 1 mm, more preferably near-infrared rays with a wavelength of approximately 0.7 μm to 2.5 μm can be employed. In this case, an infrared camera equipped with an infrared sensor that detects infrared rays (more preferably, near-infrared rays) can be employed as the camera 70 . Interference fringes can be preferably detected by detecting infrared rays.

FIG. 5 is a block diagram of camera 70 and controller 9. As shown in FIG. The hardware configuration of the controller 9 provided in the substrate processing apparatus 100 is the same as that of a general computer. That is, the control unit 9 includes a CPU that performs various arithmetic processing, a ROM that is a read-only memory that stores basic programs, a RAM that is a readable and writable memory that stores various information, and control software (programs) and data. Equipped with a magnetic disk for storing data. 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.

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

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

The timing determination unit 92 detects the interference fringes ST appearing on the upper surface of the substrate W after the previous process (first process) of processing the substrate W with the liquid, thereby starting the subsequent process (second process). A time (hereinafter, also referred to as “second processing start timing”) is determined. As will be described later, the timing determination unit 92 detects each interference fringe ST within the determination region DR set in the captured image 82 . Further, as will be described later, the detection of the interference fringes ST in the determination region DR is performed by detecting extreme points of luminance values by the extreme point detection section 921 provided in the timing determination section 92 .

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

A display unit 97 and an input unit 98 are connected to the control unit 9 . The display section 97 displays various information according to the image signal from the control section 9 . The input unit 98 is composed of input devices such as a keyboard and a mouse connected to the control unit 9, and receives input operations performed on the control unit 9 by the operator.

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

First, with the nozzle 30 at the retracted position, the main transfer robot 103 carries the substrate W to be processed received from the indexer 102 into the chamber 10 of one of the cleaning units 1 (step S10). A substrate loaded into the chamber 10 is placed on each chuck pin 26 of the spin base 21 . By closing each chuck pin 26, the substrate W is held in a horizontal posture. When the substrate W is loaded, 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 liquid-processing the substrate W. FIG. Here, first, a hydrofluoric acid process is performed to supply hydrofluoric acid from the nozzle 30 to the upper surface of the substrate W (step S11). The hydrofluoric acid supplied to the upper surface of the substrate W spreads to the outer edge of the substrate W due to the rotation of the substrate W, and the hydrofluoric acid treatment progresses over the entire substrate W. FIG. 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).

After the discharge of hydrofluoric acid from the nozzle 30 is stopped, a rinse process is performed to supply the rinse liquid (DIW) from the nozzle 30 to the upper surface of the substrate W (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. As shown in FIG. The rinse liquid supplied to the upper surface of the substrate W spreads to the outer edge of the substrate W as the substrate W rotates. Then, the hydrofluoric acid remaining on the upper surface of the substrate W is shaken off from the outer edge portion of the substrate W radially outward. The hydrofluoric acid and the rinsing liquid shaken off from the substrate W are received by the processing cup 40 and discarded as appropriate. The period during which the rinse liquid is supplied to the substrate W is, for example, 30 seconds. Also, 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, the IPA process for supplying IPA from the nozzle 30 to the upper surface of the substrate W is performed (step S13). During the IPA treatment, IPA is continuously supplied from the nozzle 30 to the upper surface of the rotating substrate W. As shown in FIG. The IPA supplied to the upper surface spreads to the outer edge of the substrate W due to the rotation of the substrate W, and the rinsing liquid (DIW) is replaced with IPA over the entire upper surface. Further, the substrate W may be heated by a heating mechanism (not shown) for the purpose of promoting replacement of DIW with IPA. The period during which IPA is supplied is, for example, 30 seconds. Further, the rotation speed of the substrate W during this period is, for example, 300 rpm.

After the ejection of IPA from the nozzles 30 is stopped, a water-repellent treatment is performed in which a water-repellent agent is supplied from the nozzles 30 to the upper surface of the substrate W (step S14). The water repellent agent supplied to the upper surface of the substrate W spreads to the outer edge of the substrate W due to the rotation of the substrate W, and the IPA is replaced with the water repellent agent over the entire upper surface, and the upper surface is improved to be water repellent. Water-repellent treatment progresses. The period during which the water repellent agent is supplied is, for example, 30 seconds. Also, the rotation speed of the substrate W during this period is, for example, 500 rpm.

After the ejection of the water repellent agent from the nozzles 30 is stopped, the same IPA treatment as in step S13 is performed (step S15). By this IPA treatment, the water-repellent agent remaining on the upper surface of the substrate W is replaced with the IPA treatment liquid.

After the ejection of IPA from the nozzles 30 is stopped, the nozzles 30 are moved from the processing position TP1 toward the retracted position. Then, a spin dry process is performed (step S16). In the spin dry process, the spin motor 22 rotates the substrate W at a higher rotational speed than in the liquid processes of steps S11 to S15 . The rotational speed at this time is, for example, 1500 rpm. Various liquids adhering to the substrate W are splashed radially outward from the outer peripheral portion by the spin drying process, are received by the inner wall of the processing cup 40, and are appropriately discharged.

When the spin drying process is completed, the chuck pins 26 release the substrate W, and the main transfer robot 103 unloads the substrate W from the chamber 10 (step S17).

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

In the above description, all the processing liquid is ejected from the nozzle 30, but part of the processing liquid may be ejected from the nozzles 60 and 65. FIG. In this case, it is preferable to move the nozzles 60 and 65 from the retracted position to the processing position at an appropriate timing, and to discharge various processing liquids onto the upper surface of the substrate W from the respective nozzles 60 and 65 .

<Regarding the process of determining the start timing of the second process>
In the substrate processing apparatus 100, the timing determining unit 92 determines the timing for starting the next process after the liquid process (first process) using liquid is completed and before the next process (second process) is started. . For example, after the ejection of IPA from the nozzles 30 is stopped in the IPA process (first process) in step S13, the timing determination unit 92 determines that the next process, i. A second process start timing at which the water repellent agent starts to be discharged is determined . As described above , the timing determination section 92 determines the timing of executing the next process according to the detection of the interference fringes ST. Here, the interference fringes ST appearing on the upper surface of the substrate W will be explained.

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

The photographed image 82b shows the state of the upper surface of the substrate W after a predetermined time has passed since the supply of the processing liquid from the nozzle 30 was stopped. When the supply of the treatment liquid is stopped while the liquid film W1 is formed, the treatment liquid on the surface of the substrate W scatters outward in the radial direction, thereby gradually thinning the liquid film W1. In the process of decreasing the film thickness, the light reflected on the upper surface of the substrate W interferes with the light reflected on the surface of the liquid film W1. Then, the portion where the phases of these two lights are matched appears as a bright band area, and the portion where the phases of these two lights are opposite appears as a dark band area. As shown in the photographed image 82b, a bright and dark striped pattern is observed by alternating bright and dark band areas in the radial direction. Here, one dark band region is assumed to be interference fringes ST. However, the bright band area may be regarded as interference fringes.

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 W1 , each interference fringe ST appears in an annular band shape (loop shape) on the substrate W and spreads outward in the radial direction while moving. Note that the interference fringes ST do not always appear in a perfect circular shape.

A photographed image 82c shows the state of the upper surface of the substrate W when time has further passed from the state shown in the photographed image 82b. As time elapses, 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 appearing on the substrate W at the same time is about three, the substrate W is covered with the liquid film W1 having a thickness close to the minimum. When such a striped pattern state is used as a guideline for starting the next process, the second process start timing is appropriately determined by detecting at least one of the interference fringes ST forming the striped pattern. can.

A photographed image 82d shows the state of the upper surface of the substrate W when time has passed from the state shown in the photographed image 82c. The final interference fringes STL appear on the substrate W in the captured image 82d. There is a possibility that the area inside the interference fringes STL is partially a dry area where there is no liquid component.

Here, it is assumed that the second treatment performed after the first treatment is the liquid treatment using the second treatment liquid. In this case, if the second processing liquid is supplied while the liquid film W1 of the first processing liquid is thick as in the photographed images 82a and 82b, it may take time to replace the first processing liquid with the second processing liquid. have a nature. In addition, when the second processing liquid is supplied in a state where the dry area is partially generated as in the photographed image 82d, the exposure time to the second processing liquid differs depending on the position of the substrate W, resulting in the 2 Process variability can occur.

Further, when the second process is a drying process such as a spin-drying process, a small amount of the first treatment liquid may be locally present when a dry region is partially generated as in the photographed image 82d. In such a case, it may take a long time to shake off even if the rotation is shifted to high speed. Therefore, it may be preferable to start high-speed rotation before the state of the captured image 82d (that is, the state where the last interference fringe STL appears). In contrast, when the liquid film W1 of the first processing liquid is thick as in the photographed images 82a and 82b and the rotation is shifted to high speed, the movement of the first processing liquid radially outward is biased. Alternatively, the shaken-off processing liquid 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 making the thickness of the liquid film W1 as thin as possible.

By appropriately setting the interference fringes ST to be detected by the timing determination unit 92 in advance according to the processing contents of each of the first and second processing, the timing determination unit 92 appropriately determines the second processing start timing. can. Next, the detection pattern of interference fringes ST will be described.

<First detection pattern>
FIG. 8 is a diagram showing a first detection pattern of interference fringes ST. A first detection pattern is a mode in which the determination region setting unit 91 sets one determination region 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 determination region DR11 coincides with the center of substrate W in photographed image 82 . By moving the interference fringes ST radially outward, the interference fringes ST pass through the photographed image 82 in the horizontal direction within the determination region DR11.

As shown in FIG. 8, the determination region DR11 is set to have such a size that it can overlap only one interference fringe ST, which is a detection target. For example, the radial width of the determination region DR11 (horizontal width on the captured image 82) is smaller than the radial interval between the adjacent interference fringes ST. Note that the interval between the interference fringes ST varies according to the thickness of the liquid film W1. For example, when the liquid film W1 is thick as shown in the photographed image 82b of FIG. The spacing is relatively large. The size of the determination region DR11 is preferably set according to the width between the interference fringes ST when the interference fringes ST to be detected appear.

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

Note that when a bright portion (a region with relatively high light intensity on the captured image 82) is captured as an interference fringe, the bright ( that is , with high light intensity) belt-like region moves radially outward. In this case, the extreme point detection unit 921 may detect the interference fringes, which are bright portions in the determination region DR11, by detecting the extreme point at which the light intensity (luminance) is the maximum value in the radial direction.

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 extremum point) is detected, and the interference fringes generated after the (n+1)th A detection time difference, which is a difference from the second detection time at which ST (second extreme value point) is detected, is calculated. Here, the second detection time may be the time at which the (n+1)th interference fringe ST is detected, or the time at which the (n+2)th and subsequent interference fringes ST are detected. Since the interval between the interference fringes ST varies 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, the smaller the thickness of the liquid film W1, the larger the detection time difference. Therefore, for example, it is preferable to experimentally determine the optimum detection time difference corresponding to the optimum thickness of the liquid film W1 for starting the second process. Then, when the actually detected detection time difference becomes the optimum detection time difference , the timing determination unit 92 determines that the interference fringes ST to be detected have been detected, and determines the second processing start timing. good too.

Further, it may be determined whether or not the interference fringes ST to be detected have been detected based on each detection time of three or more interference fringes ST within 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) point) and the second detection time difference of the third interference fringe ST (third extreme point). Then, the second processing start timing may be determined based on a comparison of the first and second detection time differences. More specifically, when the difference between the first detection time difference and the second detection time difference reaches a predetermined value, it is determined that the interference fringes ST to be detected have been detected. It is preferable that the processing start timing is determined.

As described above, as the liquid film W1 gradually becomes thinner, that is, as the appearance time of the last interference fringe STL approaches, the interval between the interference fringes ST gradually increases. Therefore, 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 region DR11 gradually increases. Improves accuracy. Therefore, the thinner the liquid film W1, the more appropriately the timing determination unit 92 can determine whether the detection time difference corresponds to the target film thickness.

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

<Second detection pattern>
FIG. 9 is a diagram showing a second detection pattern of interference fringes ST. For the second detection pattern, the determination region setting unit 91 sets a plurality of determination regions DR21 to DR23. In the example shown in FIG. 9, three determination regions DR21-DR23 are set in order from radially inward to outward. Note that the number of determination regions DR is not limited to three, and may be two or four or more.

The respective determination regions DR21-DR23 are arranged at intervals in the horizontal direction of the photographed image 82. As shown in FIG. The vertical positions of the determination regions DR21-DR23 match the center of the substrate W in the photographed image . By moving outward in the radial direction, the interference fringes ST pass through each determination region in the order of determination region DR21, determination region DR22, and determination region DR23.

Each of the determination regions DR21-DR23 is set to a size that does not include a plurality of interference fringes ST at the same time, similarly to the determination region 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 interval at which the determination regions DR21-DR23 are arranged may be set according to the interval 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 object to be detected is three interference fringes ST (interference fringes ST1 to ST3) appearing at the intervals shown, there are three determination regions corresponding to the intervals of the three interference fringes ST. DR21-DR23 are arranged. As a result, three interference fringes ST to be detected can be detected simultaneously in the determination regions DR21-DR23. That is, the timing determination unit 92 may determine that each interference fringe ST to be detected has been detected when the extremum point detection unit 921 detects the extreme point having the minimum value in all of the determination regions DR21 to DR23.

The positions of the determination regions DR21-DR23 may be arbitrarily set by the operator. In this case, for example, a photographed image 82 in which each interference fringe ST to be detected appears is obtained in advance, and the operator places a frame indicating the determination regions DR21 to DR23 on the photographed image 82 at the position of each interference fringe ST. should be moved. Thus, each determination region DR21-DR23 can be set at each position where each interference fringe ST to be detected can be detected simultaneously.

In particular, three interference fringes ST counted from the last interference fringe STL may be used as the three interference fringes ST1-ST3 to be detected. That is, the last interference fringe STL may be the innermost interference fringe ST1 to be detected, and the two interference 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 of performing the second process can be determined before the liquid film W1 becomes so thin that the interference fringes ST cannot be detected. The last fringe STL corresponds to the last detectable final extreme point.

<Third detection pattern>
FIG. 10 is a diagram showing a third detection pattern of interference fringes ST. In the third detection pattern, the determination area setting section 91 sets one determination area DR 31 on the captured image 82 . The determination region DR 31 has a shape extending in the radial direction (here, a rectangular shape extending in the horizontal direction in the captured image 82). The determination region DR 31 is set to a size that allows it to 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 a minimum value, which is an extreme value, in the determination region DR31. The timing determination unit 92 detects the interference fringes 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 fringes ST to be detected based on the distance between extreme points calculated within the determination region DR31. The distance between extremum points refers to the distance between points at which the luminance is the minimum value within the determination region DR31. In the example shown in FIG. 10, the detection targets are three interference fringes ST1-ST3. In this case, the distances L1 and L2 corresponding to the respective intervals of these three interference fringes ST1 to ST3 are set in advance, and the timing determining section 92 determines that the distance between the extreme points detected within the determination region DR31 is L1 , L2. When the interference fringes ST1-ST3 exist within the determination region DR31, the interference fringes ST1-ST3 to be detected are detected by determining that the distances between the extremum points correspond to L1 and L2.

Note that the timing determination section 92 may detect the interference fringes ST to be detected based on the number of extreme points detected in the determination region DR31. In the example shown in FIG. 10 , the detection targets are three interference fringes ST1-ST3. Therefore, the timing determining section 92 preferably determines that the detection target interference fringes ST1 to ST3 have been detected when three extreme points are detected in the determination region DR31.

The second processing start timing may be determined based on the comparison of the distances L1 and L2 between the extremum points. For example, it may be determined that the interference fringes ST1-ST3 to be detected have been detected when the difference between the extreme point distances L1 and L2 reaches a predetermined value.

FIG. 11 is a diagram showing the 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 the first process, the water repellent process (FIG. 6: step S14) is the second process, and the second process start timing (discharge of water repellent agent 10 shows the flow of processing for determining the timing to start

In the IPA process (FIG. 6: step S13), IPA is supplied from the nozzle 30 onto the upper surface of the substrate W (step S21). During this time, the camera 70 performs continuous shooting (step S22). Continuous imaging means that the camera continuously images the imaging region at regular intervals, and for example, continuous imaging may be performed at intervals of 33 milliseconds. A photographed image 82 representing the state of the upper surface of the substrate W is obtained by this continuous photographing.

When the continuous imaging is started, the determination region setting unit 91 sets the determination region DR for the captured image 82 (step S23). The determination region DR set in step S23 differs according to the detection pattern of the interference fringes 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 photographed image 82.

It should be noted that it is not essential to start continuous imaging while IPA is being discharged. For example, continuous imaging may be performed from when the substrate W is loaded into the chamber 10 until it is unloaded.

When the determination region DR is set, the supply of 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 IPA is stopped, the IPA on the substrate W is shaken radially outward by centrifugal force. As a result, the liquid film W1 gradually becomes thinner, and interference fringes ST begin to appear.

The extremum point detection unit 921 detects an extremum point having a minimum luminance value in the radial direction in the determination region DR (step S25). As a result, the interference fringes ST overlapping the determination region DR are detected as extreme points at which the minimum values are obtained.

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 fringes ST to be detected have been detected (step S26). The specific contents of this determination differ depending on the detection pattern of the interference fringes ST. If it is determined that the interference fringes ST to be detected have not been detected (NO in step S26), the process returns to step S25 to continue detection of the minimum value.

For example, in the case of the first detection pattern shown in FIG. 8, the timing determination unit 92 determines when the detection time difference between the interference fringes ST detected in the determination region DR11 corresponds to the preset optimum detection time difference. of interference fringes ST are detected. In the case of the second detection pattern shown in FIG. 9, the timing determination unit 92 determines that the interference fringes ST1 to ST3, which are the detection targets, are detected when the interference fringes ST are detected simultaneously in the determination regions DR21 to DR23. judge. Further, in the case of the third detection pattern shown in FIG. 10, the timing determination unit 92 determines that the distances between extreme value points between the points where the minimum values are detected correspond to the preset distances L1 and L2 in the determination region 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 fringes ST to be inspected have been detected (YES in step S26), the timing determination unit 92 determines the second process start timing (step S27). The timing determination unit 92 determines the second process start timing according to the detection completion time at which the interference fringes ST to be detected is detected (the time at which the minimum value corresponding to the interference fringes ST to be detected is detected). . For example, the timing determining unit 92 sets the time obtained by adding a predetermined delay time from the detection completion time as the second processing start timing.

When the second processing start timing is determined in step S27, the water repellent agent is started to be discharged from the nozzle 30 onto the upper surface of the substrate W at the second processing start timing (step S28). As a result, the water-repellent treatment ( FIG. 6 : step S14) is started. In step S<b>28 , the controller 9 causes the nozzle 30 to eject 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 the water-repellent process, which is the next process, in accordance with the second process start timing. Therefore, the control unit 9, the nozzle 30, and the mechanism for supplying the water repellent agent to the nozzle 30 can be an example of the second processing execution unit.

In step S27, the length of the delay time to be added from the detection completion time to determine the second process start timing may be determined prior to experimental substrate processing. Specifically, after the interference fringes ST to be detected are detected, the water-repellent treatment is started at different delay times, and the resulting hydrophobized state of the substrate W is evaluated. An optimal delay time may be determined based on this evaluation result.

In step S27, it is not essential to set the second process start timing to the time obtained by adding the predetermined delay time to the detection completion time. For example, the second process start timing may be the detection completion time. In this case, when it is determined in step S26 that the interference fringes ST to be detected have been detected, the ejection of the water repellent agent is immediately started.

FIG. 11 shows the process of determining the start timing of the second process when the first process is the IPA process and the second process is the water-repellent process, but the combination of the first and second processes is limited to this. not to be For example, even if the first treatment is the IPA treatment after the water-repellent treatment (FIG. 6: step S15) and the second treatment is the spin dry treatment (FIG. 6: step S16), the second treatment start timing is determined. Processing can be applied. In this case, the control unit 9 controls the spin motor 22 of the spin chuck 20 according to the second processing 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, which is the second process, in accordance with the second process start timing. Therefore, the control section 9 and the spin motor 22 can serve as a second processing section.

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

When the second treatment is liquid treatment (for example, when the first treatment is IPA treatment (FIG. 6: step S13) and the second treatment is water repellent treatment (FIG. 6: step S14)), the first The second treatment liquid can be supplied after the film thickness of the treatment liquid is made as thin as possible. In this case, since the amount of the first processing liquid on the substrate W can be reduced, the replacement of the first processing liquid with the second processing liquid can be promoted. Thereby, the processing time of the second processing can be shortened. In addition, 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 the drying process (when the first process is the IPA process (FIG. 6: step S15) and the second process is the spin dry process (step S16)) , the substrate processing apparatus 100 performs The drying process can be started while the film thickness of the first treatment liquid is appropriate. Therefore, excessive swelling of the liquid film can be suppressed. Thereby, the substrate surface can be uniformly processed.

<Condition setting for detecting interference fringes ST>
FIG. 12 shows a setting screen SW1 for setting conditions for detecting the interference fringes ST. In the substrate processing apparatus 100 , the operator determines the processing content to be executed in each cleaning processing unit 1 on a processing program creation screen (not shown) displayed on the display section 97 . 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 part thereof. When the operator performs a predetermined operation on the setting screen SW1, the determination region setting section 91 sets the conditions of the determination region DR according to the operation input. In step S23 shown in FIG. 11, the determination region setting unit 91 sets the determination region DR that matches the set conditions on the captured image 82 for detecting the interference fringes ST to be detected.

Display areas DA1 to DA6 for displaying various information are defined in the setting screen SW1. The display area DA1 displays the contents of the first process and the second process. In the display area DA1, the contents of the specified processing, such as processing conditions 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 during the discharge of the processing liquid, are displayed. Each parameter is displayed. It should be noted that in the display area DA1, the change of each parameter may be accepted based on the operator's input operation. When the operator designates the contents of the first process or the second process in the display area DA1, the start timing of the second process is determined. Areas indicating detection patterns and position patterns selected in display areas DA2 and DA3, which will be described later, are defined in the display area DA1.

When the first and second processes are set, the timing determination unit 92 automatically determines the interference fringes ST to be detected based on those process conditions. As a preliminary preparation for this determination process, the interference fringes ST to be detected may be specified in advance for each different condition for the first process. In this case, a suitable start timing for the second process is determined for each case in which the first process is performed by changing the conditions of the treatment liquid, the discharge amount, and the number of revolutions, and the interference fringes ST corresponding to the start timing are determined. should be determined.

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

Buttons BT21 to BT24 for selecting the position pattern of the determination area DR are displayed in the display area DA3. When the operator operates one of the buttons BT21-BT24, the position pattern of the determination region DR is set according to the operated button. The contents assigned to the buttons BT21-BT23 are preferably 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 among the buttons BT21 to BT23. In the case of the second detection pattern, it is preferable that the distances in the radial direction between the determination regions DR21 -DR23 are different between the buttons BT21-BT23.

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

Buttons BT31 to BT33 for selecting the type of substrate W to be processed are displayed in the display area DA4. The type of the substrate W depends on 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 for water (hydrophobicity/hydrophilicity), and the like. Preferably, each condition that affects appearance is addressed.

A captured image 82 is displayed in the display area DA5. The photographed image 82 may be a photographed image obtained by imaging the camera 70 in the past, or may be a photographed image obtained by imaging the camera 70 in real time. A rectangular frame indicating the determination region DR is preferably displayed on the captured image 82 according to the detection pattern and the position pattern selected in the display regions DA2 and DA3. For example, one determination region DR11 may be displayed when the first detection pattern is selected.

An operation to change the position of the determination region DR on the captured image 82 may be accepted . For example, determination region DR may be changed to a post-movement position by accepting a drag operation. The movement operation of 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 determination region DR can be easily set because the position of the determination region DR can be changed in accordance with the moving direction (outward in the radial direction) of the interference fringes ST.

When displaying a photographed image 82 obtained by past imaging, the interference fringes ST to be detected appear in the photographed image 82 at the time of transition from the first processing specified in the display area DA1 to the second processing. A photographed image 82 (for example, photographed images 82b and 82c shown in FIG. 7) can be employed. In this case, since the operator can move the frame of the determination region DR while viewing the interference fringes ST, the determination region DR can be set at an appropriate position. Further, moving image display may be performed by continuously reproducing a series of shot images 82 obtained by continuous shooting in the display area DA5. In this case, various buttons for controlling display such as playback or stop may be prepared to accept display control by the operator. This allows the operator to appropriately set the conditions for the determination region DR while confirming how the interference fringes ST appear.

The display area DA6 is an area for receiving input of the target film thickness. The target film thickness is the thickness of the liquid film W1 of the first processing liquid that serves as a guide when starting the second processing. When the target film thickness is input, the timing determining section 92 specifies the interference fringes ST appearing when corresponding to the target film thickness. As a preliminary preparation for this specific process, the thickness of the liquid film W1 is measured after the ejection of the treatment liquid from the nozzles 30 is stopped in the first process. It is preferable to specify the relationship between each appearance time when each interference fringe ST appears and the thickness of the liquid film W1. In this case, it is preferable to determine the thickness of the liquid film W1 corresponding to the appearance timing of each interference fringe ST for each case in which the first process is performed by changing the processing liquid, the discharge amount, and the rotation speed. . Note that the position of the substrate W where the thickness is measured may be the center of the substrate W, the outer edge, or an intermediate position therebetween.

When a target film thickness is input in the display area DA6, in the display areas DA2 and DA3 , a detection pattern and a position pattern corresponding to the interference fringes ST corresponding to the target film thickness are displayed. can be narrowed down and displayed. In this case, it is preferable to determine in advance the detection pattern and the position pattern 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 fringes ST to be detected may not be specified because the inputted target film thickness is not reached. In such a case, a message such as "undetectable, lengthen the step time" may be displayed. This makes it possible to prompt the operator 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 those already described may be given the same reference numerals or reference numerals with additional alphabetic characters, and detailed description thereof may be omitted.

FIG. 13 is a diagram showing a substrate processing apparatus 100A of the second embodiment. The control section 9A of the substrate processing apparatus 100A has a timing determination section 92A. The timing determination section 92A has a feature vector extraction section 922 and a classifier K2.

The feature vector extraction unit 922 extracts a feature vector, which is an array of multiple 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, the pixel value or the sum of brightness in grayscale, the standard deviation of the pixel value or brightness, and the like.

Based on the feature vectors extracted by the feature vector extraction unit 922, the classifier K2 classifies the captured image 82 into a first class indicating that it is an image that serves as a guideline for determining the second processing start timing, and a second processing start class. The image is classified into the second class, which indicates that the image is not used as a guideline for timing determination.

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

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

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

As teacher data used for machine learning by the machine learning unit 80, for example, the captured image 82 obtained by the camera 70 (or its feature vector) can be taught with a class. The photographed image 82 acquired by the camera 70 can be provided to the server 8 from the substrate processing apparatus 100A via the communication section 99. FIG.

For example, when the photographed images 82a to 82d shown in FIG. 7 are used as teacher data, the photographed image 82 serving as a guideline for the second processing start timing is the photographed image 82c (that is, the number of interference fringes ST appearing on the substrate W is 3 states), the first class indicating that the second processing start timing is a guide for the photographed image 82c is taught. Then, it is preferable to teach the second class indicating that the photographed images 82a, 82b, and 82d are not a reference for the second processing start timing. By preparing a large number of such teacher data and making the machine learning unit 80 learn, the machine learning unit 80 classifies the photographed image 82 into the first class and the second class based on the feature vector. to generate a container K2.

The classifier K2 classifies 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 for water (hydrophobicity/hydrophilicity)). A plurality of types of classifiers K2 may be generated for each process or for each different condition 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 substrate W or for each different condition of the first process.

A classifier K2 may be provided from the server 8 to each substrate processing apparatus 100A by communicably connecting a plurality of substrate processing apparatuses 100A to the server 8. FIG.

It is not essential that the classifier K2 is provided by the server 8; For example, the classifier K2 may be provided to the controller 9A via a storage medium such as optical media or flash memory. Further, the classifier K2 may be generated in the substrate processing apparatus 100A by including the machine learning unit 80 in the substrate processing apparatus 100A .

In the substrate processing apparatus 100A, the process of determining the second process start timing is performed by the timing determination unit 92A classifying the series of captured images 82 acquired by the camera 70 after step S24 (supply of IPA is stopped) shown in FIG. By the class classification performed by the device K2, the photographed image 82 that serves as a guideline for the second processing start timing is detected. Then, the timing determination unit 92A sets the detection time at which the photographed image 82 is detected or the time obtained by adding a predetermined delay time to the detection time as the second processing start timing.

In this embodiment, the classifier K2 performs class classification based on the entire photographed image 82 . Therefore, the entire photographed image 82 is set as the determination area. Further, as described above, the classifier K2 is generated by machine learning using the photographed image 82 in which the class is taught according to the appearance state of the interference fringes ST as teacher data. For this reason, the timing determination unit 92A determines the start timing of the second process according to the interference fringes ST moving radially outward in the determination area (extreme points regarding the light intensity on the captured image 82). becomes.

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

Note that it is not essential to use the entire photographed image 82 as teacher data. For example, only the image portion within the determination region 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 calculations can be reduced.

Although the present invention has been described in detail, the above description is, in all aspects, illustrative and not intended to limit the present invention. It is understood that numerous variations not illustrated can be envisioned without departing from the scope of the invention. Each configuration described in each of the above embodiments and 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 unit 8 server 9, 9A control unit 10 chamber 20 spin chuck 21 spin base 22 spin motor 24 rotating shaft 26 chuck pin 30, 60, 65 nozzle 31 ejection head 70 camera 71 lighting unit 80 machine Learning unit 82, 82a, 82b, 82c, 82d Captured image 91 Judgment region setting unit 92, 92A Timing determination unit 96 Storage unit 97 Display unit 98 Input unit 99 Communication unit 921 Extreme point detection unit 922 Feature vector extraction unit CX Rotation axis DR Determination area DR11, DR21 , DR22, DR23, DR31 Determination area K2 Classifier (image determination unit)
ST, ST1 , ST2, ST3, STL Interference fringes W Substrate W1 Liquid film (of first processing liquid)

Claims (24)

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 position by the step (a) about a vertical axis of rotation;
(c) supplying a first processing liquid to the upper surface of the substrate rotated by the step (b);
(d) stopping the supply of the first treatment liquid after step (c);
(e) thinning the film of the first processing liquid remaining on the upper surface of the substrate after step (d);
(f) photographing the upper surface of the substrate in step (e) with a camera;
(g) the extreme point at which the light intensity in the radial direction orthogonal to the rotation axis is maximum or minimum within the determination area set on the upper surface of the substrate of the photographed image acquired in the step (f); determining a timing for performing a second process on the substrate according to the radially outward movement ;
(h) performing the second process on the substrate according to the timing determined in step (g);
including
The step (g) is
(g1) determining the timing when the time difference between the detection of one extreme point and the detection of the next extreme point in the determination region corresponds to a preset detection time difference; A method of processing a substrate , comprising : The substrate processing method of claim 1 ,
The step (g) is
(g2) Within the determination region, a first time that is the time difference between the detection of the first extreme point and the detection of the second extreme point; determining the timing when a second time, which is the time difference until the three extreme points are detected , corresponds to a preset detection time difference ;
A method of processing a substrate, comprising: 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 position by the step (a) about a vertical axis of rotation;
(c) supplying a first processing liquid to the upper surface of the substrate rotated by the step (b);
(d) stopping the supply of the first treatment liquid after step (c);
(e) thinning the film of the first processing liquid remaining on the upper surface of the substrate after step (d);
(f) photographing the upper surface of the substrate in step (e) with a camera;
(g) the extreme point at which the light intensity in the radial direction orthogonal to the rotation axis is maximum or minimum within the determination area set on the upper surface of the substrate of the photographed image acquired in the step (f); determining a timing for performing a second process on the substrate according to the radially outward movement ;
(h) performing the second process on the substrate according to the timing determined in step (g);
including
The step (g) is
(g3) an extreme point having a preset first distance between a first extreme point detected in the determination region and a second extreme point radially outwardly away from the first extreme point; determining the timing when corresponding to the distance between substrates. The substrate processing method of claim 3 ,
The step (g) is
(g5) the first distance, and a second distance between the second extreme point and a third extreme point radially outwardly away from the second extreme point in the determination region ; corresponding to a preset distance between extreme points ;
A method of processing a substrate, comprising: 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 position by the step (a) about a vertical axis of rotation;
(c) supplying a first processing liquid to the upper surface of the substrate rotated by the step (b);
(d) stopping the supply of the first treatment liquid after step (c);
(e) thinning the film of the first processing liquid remaining on the upper surface of the substrate after step (d);
(f) photographing the upper surface of the substrate in step (e) with a camera;
(g) the extreme point at which the light intensity in the radial direction orthogonal to the rotation axis is maximum or minimum within the determination area set on the upper surface of the substrate of the photographed image acquired in the step (f); determining a timing for performing a second process on the substrate according to the radially outward movement ;
(h) performing the second process on the substrate according to the timing determined in step (g);
including
The determination area includes a first determination area and a second determination area radially outwardly away from the first determination area,
The step (g) is
(g4) determining the timing based on simultaneous detection of a first extreme point detected in the first determination area and a second extreme point detected in the second determination area; A method of processing a substrate, comprising : The substrate processing method of claim 5,
The determination area includes the first determination area, the second determination area, and a third determination area radially outwardly away from the second determination area,
The step (g4) is
Detection of the first extreme point in the first determination area, detection of the second extreme point in the second determination area, and detection of the third extreme point in the third determination area are performed simultaneously. Determining the timing based on the substrate processing method. The substrate processing method according to claim 5 or claim 6 ,
(i) changing the relative position in the radial direction of the second determination region with respect to the first determination region before step (g);
A substrate processing method further comprising: 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 position by the step (a) about a vertical axis of rotation;
(c) supplying a first processing liquid to the upper surface of the substrate rotated by the step (b);
(d) stopping the supply of the first treatment liquid after step (c);
(e) thinning the film of the first processing liquid remaining on the upper surface of the substrate after step (d);
(f) photographing the upper surface of the substrate in step (e) with a camera;
(g) the extreme point at which the light intensity in the radial direction orthogonal to the rotation axis is maximum or minimum within the determination area set on the upper surface of the substrate of the photographed image acquired in the step (f); determining a timing for performing a second process on the substrate according to the radially outward movement ;
(h) performing the second process on the substrate according to the timing determined in step (g);
including
The step (g) is
(g6) setting the timing to be a time obtained by adding a predetermined delay time to the time at which the last extremum point among the plurality of extremum points is detected in the determination region; Processing method. A substrate processing method according to any one of claims 1 to 8 ,
The substrate processing method, 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. A substrate processing method according to any one of claims 1 to 9 ,
The substrate processing method, wherein the camera is an infrared camera. A substrate processing method according to any one of claims 1 to 10 ,
The substrate processing method, wherein the second processing is a processing of supplying a second processing liquid different from the first processing liquid onto the upper surface of the substrate. A substrate processing method according to any one of claims 1 to 10 ,
The substrate processing method, wherein the second processing is processing for removing the first processing liquid remaining on the upper surface of the substrate by increasing the rotational speed of the substrate as compared to the step (e). A substrate processing apparatus for performing liquid processing on the upper surface of a substrate rotating in a horizontal posture,
a substrate holder that holds the substrate in a horizontal posture;
a rotation unit that rotates a target substrate, which is a substrate held by the substrate holding unit, about a rotation axis in a vertical direction;
a first processing liquid supply unit that supplies a first processing liquid to the upper surface of the target substrate;
a camera for photographing the upper surface of the target substrate;
A radial direction of an extreme point at which the light intensity in a radial direction orthogonal to the rotation axis becomes a maximum value or a minimum value within the determination area set on the upper surface of the target substrate in the photographed image acquired by the camera. a timing determination unit that determines the timing of performing the second process on the target substrate according to the outward movement;
a second processing execution unit that performs a second process on the target substrate according to the timing determined by the timing determination unit;
with
The timing determining unit determines the timing when a time difference from detection of one extremum point to detection of the next extremum point in the determination region corresponds to a preset detection time difference. A substrate processing apparatus. The substrate processing apparatus of claim 13,
The timing determination unit is configured to detect a first time, which is a time difference from detection of a first extreme point to detection of a second extreme point, and detection of the second extreme point in the determination region. the substrate processing apparatus, determining the timing when a second time, which is the time difference from the time the third extreme point is detected, corresponds to a preset detection time difference. A substrate processing apparatus for performing liquid processing on the upper surface of a substrate rotating in a horizontal posture,
a substrate holder that holds the substrate in a horizontal posture;
a rotation unit that rotates a target substrate, which is a substrate held by the substrate holding unit, about a rotation axis in a vertical direction;
a first processing liquid supply unit that supplies a first processing liquid to the upper surface of the target substrate;
a camera for photographing the upper surface of the target substrate;
A radial direction of an extreme point at which the light intensity in a radial direction orthogonal to the rotation axis becomes a maximum value or a minimum value within the determination area set on the upper surface of the target substrate in the photographed image acquired by the camera. a timing determination unit that determines the timing of performing the second process on the target substrate according to the outward movement;
a second processing execution unit that performs a second process on the target substrate according to the timing determined by the timing determination unit;
with
The timing determination unit presets a first distance between a first extreme point detected in the determination region and a second extreme point radially outwardly away from the first extreme point. A substrate processing apparatus that determines the timing when corresponding to a distance between extreme points . The substrate processing apparatus of claim 15,
The timing determination unit is configured to provide a second distance between the first distance and a third extreme point radially outwardly away from the second extreme point and the second extreme point in the determination area. and a distance corresponding to a preset distance between extreme points. A substrate processing apparatus for performing liquid processing on the upper surface of a substrate rotating in a horizontal posture,
a substrate holder that holds the substrate in a horizontal posture;
a rotation unit that rotates a target substrate, which is a substrate held by the substrate holding unit, about a rotation axis in a vertical direction;
a first processing liquid supply unit that supplies a first processing liquid to the upper surface of the target substrate;
a camera for photographing the upper surface of the target substrate;
A radial direction of an extreme point at which the light intensity in a radial direction orthogonal to the rotation axis becomes a maximum value or a minimum value within the determination area set on the upper surface of the target substrate in the photographed image acquired by the camera. a timing determination unit that determines the timing of performing the second process on the target substrate according to the outward movement;
a second processing execution unit that performs a second process on the target substrate according to the timing determined by the timing determination unit;
with
The determination area includes a first determination area and a second determination area radially outwardly away from the first determination area,
The timing determination unit determines the timing based on simultaneous detection of a first extreme point detected in the first determination region and a second extreme point detected in the second determination region. A substrate processing apparatus. 18. The substrate processing apparatus of claim 17,
The determination area includes the first determination area, the second determination area, and a third determination area radially outwardly away from the second determination area,
The timing determination unit detects the first extreme point in the first determination area, detects the second extreme point in the second determination area, and detects a third extreme point in the third determination area. A substrate processing apparatus, wherein the timing is determined based on detecting and occurring simultaneously. The substrate processing apparatus according to claim 17 or 18,
The substrate processing apparatus, wherein the timing determination unit changes a relative position in a radial direction of the second determination area with respect to the first determination area before determining the timing. A substrate processing apparatus for performing liquid processing on the upper surface of a substrate rotating in a horizontal posture,
a substrate holder that holds the substrate in a horizontal posture;
a rotation unit that rotates a target substrate, which is a substrate held by the substrate holding unit, about a rotation axis in a vertical direction;
a first processing liquid supply unit that supplies a first processing liquid to the upper surface of the target substrate;
a camera for photographing the upper surface of the target substrate;
A radial direction of an extreme point at which the light intensity in a radial direction orthogonal to the rotation axis becomes a maximum value or a minimum value within the determination area set on the upper surface of the target substrate in the photographed image acquired by the camera. a timing determination unit that determines the timing of performing the second process on the target substrate according to the outward movement;
a second processing execution unit that performs a second process on the target substrate according to the timing determined by the timing determination unit;
with
wherein the timing determination unit sets the time obtained by adding a predetermined delay time to the time at which the last extremal point among the plurality of extremal points is detected in the determination area as the timing; Device. The substrate processing apparatus according to any one of claims 13 to 20,
The substrate processing apparatus, wherein the second processing execution unit starts the second processing while the film of the first processing liquid remains on the entire upper surface of the target substrate. The substrate processing apparatus according to any one of claims 13 to 21,
A substrate processing apparatus, wherein the camera is an infrared camera. The substrate processing apparatus according to any one of claims 13 to 22,
The substrate processing apparatus, wherein the second process is a process of supplying a second processing liquid different from the first processing liquid to the upper surface of the target substrate. The substrate processing apparatus according to any one of claims 13 to 22,
The substrate processing apparatus according to claim 1, wherein the second processing is processing for removing the first processing liquid remaining on the upper surface of the target substrate by increasing the rotational speed of the rotating portion.

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