JP7122192B2 - SUBSTRATE PROCESSING METHOD, SUBSTRATE PROCESSING APPARATUS, AND SUBSTRATE PROCESSING SYSTEM - Google Patents

Description

The present invention relates to a technique for processing a substrate by ejecting a processing liquid from a nozzle that moves over the substrate, and more particularly to a technique for detecting displacement of the nozzle. 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.

2. Description of the Related Art In the manufacturing process of semiconductor devices and the like, substrate processing such as cleaning processing and resist coating processing is performed by supplying various processing liquids such as pure water, photoresist liquid, and etching liquid to substrates. As an apparatus for performing liquid processing using these processing liquids, there is a substrate processing apparatus that ejects processing liquid from nozzles onto the surface of the substrate while rotating the substrate.

Patent Document 1 discloses a technique for detecting whether the nozzles are normally arranged at the processing positions when detecting whether the processing liquid is being discharged from the nozzles arranged at the processing positions.

Specifically, a reference image is acquired in advance when the nozzle is accurately positioned at the processing position, and the image when the nozzle is moved to the processing position for each recipe and the previously acquired reference image are combined. compare. It is described that when a nozzle is displaced from the processing position by a predetermined threshold value, it is determined that the nozzle is positioned abnormally.

JP 2015-173148 A

However, in the case of the prior art, it was difficult to determine misalignment of moving nozzles. In the case of the prior art, positional anomalies are detected in one reference image and one processing position. In some cases, the surface of the substrate is liquid-processed by moving it over the substrate while discharging the processing liquid from the nozzle. At this time, there is a demand for a technique for detecting whether or not the nozzles are correctly moving in the predetermined processing section.

However, when the moving nozzle is imaged, the shape and size on the image change moment by moment while moving between the initial position and the final position. Therefore, if an image of a nozzle at a specific position is used as a reference image and matched with an image of a moving nozzle, the shape of the nozzle changes on the image, resulting in a decrease in matching accuracy. For this reason, it is difficult to accurately determine the positional abnormality.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a technique for accurately detecting misalignment of a moving nozzle.

In order to solve the above problems, a first aspect is a substrate processing method for processing a substrate, comprising: (a) a step of moving a nozzle within a predetermined processing section extending in a horizontal direction; (c) when the nozzles are located at the first and second ends of the processing section in step (b), (d) moving the nozzle within the processing section; (e) moving the nozzle within the processing section in step (d); and (f) determining whether or not the plurality of captured images obtained in step (e) correspond to the first end and the second end based on a predetermined determination rule. (g) said first and said second reference images and said first and second actual images determined by said step (f) to correspond to said first edge and said second edge, respectively; and detecting positional deviation of the nozzles arranged at each end of the processing section in the step (d).

A second aspect is the substrate processing method of the first aspect, further comprising: (h) a step of holding the substrate to be processed on a substrate holding part after the step (c) and before the step (d). include.

A third aspect is the substrate processing method of the first aspect or the second aspect, wherein the step (d) includes (d1) moving the nozzle from a position near the first end toward the second end. and the step (f) includes (f1) a step of determining whether or not the images correspond to the first end and the second end based on the difference between the successive captured images.

A fourth aspect is the substrate processing method according to any one of the first to third aspects, wherein the step (c) comprises: (c1) the nozzle moving in the middle of the processing section in the step (b); wherein the step (g) comprises (g1) the intermediate reference image and the step (e) moving the middle of the processing interval A step of detecting displacement of the nozzle moving in the middle of the processing section in the step (d) based on comparison with an intermediate real image obtained by imaging the nozzle.

A fifth aspect is the substrate processing method according to any one of the fourth aspects, wherein the step (g) includes (g2) the nozzle in the vertical direction based on the intermediate reference image and the intermediate real image. and detecting the positional deviation of the .

A sixth aspect is the substrate processing method of the fourth aspect or the fifth aspect, wherein: (i) the trajectory of the nozzle moving in the processing section is determined from the plurality of intermediate reference images registered in the step (c1); wherein the step (g) is a step of (g3) detecting the displacement of the nozzle in the vertical direction based on the intermediate real image and the reference trajectory information. including.

A seventh aspect is the substrate processing method according to any one of the fourth to sixth aspects, wherein the step (c1) includes (c11) the nozzle moving in the middle of the processing section in the step (b). (c12) after the step (c11), registering one of the plurality of captured images obtained by capturing the first intermediate reference image among the plurality of captured images as a first intermediate reference image; registering, as a second intermediate reference image, a photographed image that follows the reference image and has a degree of matching with the first intermediate reference image equal to or lower than a predetermined threshold.

An eighth aspect is the substrate processing method according to any one of the first aspect to the seventh aspect, wherein the step (a) includes (a1) the controller moving the nozzle from the first end to the second end. transmitting a control signal for movement to a nozzle moving unit, wherein the step (b) comprises (b1) capturing a plurality of captured images by imaging the nozzle in response to the transmission of the control signal. include.

A ninth aspect is the substrate processing method of the eighth aspect, wherein the step (b) includes (b2) control information indicated by the control signal and a plurality of captured images acquired by imaging according to the control signal. and a step of recording in association with each other.

A tenth aspect is the substrate processing method of the ninth aspect, wherein the step (c) includes (c2) displaying a series of photographed images obtained in the step (b) continuously in the order in which they were obtained. wherein the step (c2) comprises: (c21) specifying the control information; and (c22) displaying the captured image corresponding to the control information specified in the step (c21) on the display unit. and displaying to.

An eleventh aspect is a substrate processing apparatus for processing a substrate, comprising: a substrate holding portion for holding a substrate in a horizontal posture; a nozzle for supplying a processing liquid to the substrate held by the substrate holding portion; a nozzle moving unit that moves within a predetermined processing section extending in a direction; a camera that acquires a photographed image by capturing an image of the nozzle that moves within the processing section; a reference image registering unit for registering first and second reference images obtained by imaging the nozzles at two ends with the camera; and detecting displacement of the nozzles at the first end and the second end. and a positional deviation detection unit, wherein the positional deviation detection unit detects, based on a predetermined determination rule, the first an image determination unit for determining whether or not the image corresponds to each of the edge and the second edge; the first and second reference images; and the image determination unit corresponding to each of the first edge and the second edge. and an image comparison unit for comparing the first and second real images determined to be true.

A twelfth aspect is the substrate processing apparatus according to the eleventh aspect, wherein the image determination unit includes a feature vector calculation unit for extracting a plurality of types of feature vectors from each of the plurality of captured images, a classifier that classifies each of the plurality of captured images into classes corresponding to different positions of the nozzle according to the vector, wherein the plurality of classes corresponds to each of the first end and the second end. Contains classes that

A thirteenth aspect is a substrate processing system including a substrate processing apparatus that processes a substrate and a server that performs data communication with the substrate processing apparatus, wherein the substrate processing apparatus includes a substrate holding section that holds a substrate in a horizontal position. a nozzle for supplying the processing liquid to the substrate held by the substrate holding unit; a nozzle moving unit for moving the nozzle within a predetermined processing section extending in a horizontal direction; and the nozzle moving within the processing section. registering a camera for obtaining a photographed image by performing the above-mentioned processing, and registering first and second reference images obtained by the camera photographing the nozzles at the first end and the second end, which are both ends of the processing section. a reference image registration unit; a positional deviation detection unit that detects positional deviation of the nozzles at the first end and the second end; and a communication unit that performs data communication with the server, wherein the positional deviation detection unit comprises: and determining whether or not an actual image obtained by imaging the nozzle moving in the processing section with the camera corresponds to the first end and the second end based on a predetermined determination rule. and an image for comparing the first and second reference images with the first and second real images determined by the image determination unit to correspond to the first edge and the second edge, respectively. a comparison unit, wherein the image determination unit includes a feature vector calculation unit that extracts a plurality of types of feature vectors from the captured image; and a feature vector calculation unit that extracts a plurality of types of feature vectors from the captured image; a classifier for classifying into a plurality of classes corresponding to different positions, the plurality of classes including a class of images corresponding to each of the first end and the second end; a machine learning unit that generates the classifier by machine learning using the plurality of photographed images for which any one of the classes is taught as training data, and the classifier is provided from the server to the substrate processing apparatus. .

According to the substrate processing method of the first mode, deviation of the movement range of the nozzle in the processing section can be detected.

According to the substrate processing method of the second aspect, deviation of the movement range of the nozzle can be detected when processing the substrate.

According to the substrate processing method of the third aspect, it is possible to detect that the nozzle is stopped at the first end and the second end of the processing section by taking the difference between the successive photographed images. This makes it possible to easily identify the actual images corresponding to the first end and the second end of the processing section.

According to the substrate processing method of the fourth aspect, misalignment of the nozzle moving in the middle of the processing section can be detected.

According to the substrate processing method of the fifth aspect, positional deviation in the vertical direction can be detected.

According to the substrate processing method of the sixth aspect, the positional deviation of the nozzle in the vertical direction can be detected from the reference trajectory information.

According to the substrate processing method of the seventh aspect, the intermediate reference image can be automatically registered. Therefore, many reference images can be efficiently registered.

According to the substrate processing method of the eighth aspect, imaging of the nozzle is performed according to the control signal for moving the nozzle. Therefore, it is possible to automatically obtain a reference image indicating the reference position of the moving nozzle.

According to the substrate processing method of the ninth aspect, by designating the control information, it is possible to easily search for the target photographed image.

According to the substrate processing method of the tenth aspect, when there are a plurality of control signals and a series of reference images corresponding to each control signal, the target reference image can be displayed on the display section by designating the control information. . As a result, the operator can efficiently specify the reference image to be registered from among many captured images.

According to the substrate processing apparatus of the eleventh aspect, deviation of the movement range of the nozzle in the processing section can be detected.

According to the substrate processing apparatus of the twelfth aspect, the classifier can identify the actual images corresponding to the first end and the second end of the processing section PS1.

According to the substrate processing system of the thirteenth aspect, it is possible to detect the deviation of the movement range of the nozzle in the processing section. Also, the real images corresponding to each of the first and second ends of the processing section PS1 can be identified by a classifier provided by the server.

It is a figure which shows the whole structure of the substrate processing apparatus 100 of 1st Embodiment. 2 is a plan view of the cleaning unit 1 of the first embodiment; FIG. 1 is a vertical cross-sectional view of a cleaning unit 1 of a first embodiment; FIG. 4 is a diagram showing a positional relationship between a camera 70 and a nozzle 30; FIG. 3 is a block diagram of camera 70 and control unit 9. FIG. 9 is a flow chart showing a procedure of advance preparation for detection processing by a positional deviation detection unit 91. FIG. 9 is a flowchart showing a procedure of detection processing by a positional deviation detection unit 91; FIG. 7 is a diagram showing an example of an image obtained by imaging an imaging area PA including the tip of the nozzle 30 in the processing section PS1 with the camera 70; FIG. 4 is a diagram conceptually showing the registration processing of a reference image RP; FIG. 4 is a diagram conceptually showing how a real image GP corresponding to a reference image RP is specified; 4 is a diagram conceptually showing reference trajectory information ST1. FIG. 4 is a time chart showing how the nozzles 30 are continuously imaged. FIG. 10 is a diagram showing a registration screen W1 for registering a reference image RP; It is a figure which shows 9 A of control parts of 2nd Embodiment. FIG. 4 is a diagram conceptually showing a classifier K2;

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 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. In addition, unless otherwise specified, "on" includes not only the case where two elements are in contact with each other, but also the case where two elements are separated from each other.

<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. Here, the substrate processing apparatus 100 performs a cleaning process using a chemical solution and a rinsing liquid such as pure water on the 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 rinsing liquid are collectively referred to as "processing liquid". In addition to the cleaning process, the "processing liquid" includes coating liquids such as photoresist liquids for film formation, chemical liquids for removing unnecessary films, and chemical liquids for etching. .

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 . In FIG. 1, one of the cleaning units 1 stacked in three stages is schematically shown. 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 .

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 plan view of the cleaning unit 1 of the first embodiment. FIG. 3 is a 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 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 extending in the vertical direction and surrounding on all four sides, a ceiling wall 12 closing the upper side of the side walls 11 , and a floor wall 13 closing 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. 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 are provided on a part of the side wall 11 of the chamber 10 (both are shown in the figure). omit).

A fan filter unit (FFU) 14 is attached to the ceiling wall 12 of the chamber 10 for further purifying the air in the clean room in which the substrate processing apparatus 100 is installed and supplying 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 in air in the clean room and sending it out into the chamber 10 . The FFU 14 creates a clean air downflow in the processing space within the 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 . The plurality of chuck pins 26 are arranged at equal intervals along the circumference corresponding to the outer diameter 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°. A plurality of chuck pins 26 are interlocked and driven by a link mechanism (not shown) housed in the spin base 21 . The spin chuck 20 grips the substrate W with each of the plurality of chuck pins 26 in contact with the outer peripheral edge of the substrate W, thereby placing the substrate W above the spin base 21 in a horizontal position close to the holding surface 21a. and hold (see Figure 3). Further, the spin chuck 20 releases the grip of the substrate W by separating each of the plurality of chuck pins 26 from the outer peripheral edge of the substrate W. As shown in FIG.

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 .

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) 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. move 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, the predetermined processing section PS1 extending in the horizontal direction is moved. Note that moving the nozzle 30 within the processing section PS1 is the same as moving the ejection head 31 at the tip within the processing section PS1.

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) ejects the treatment liquid while moving in the treatment section PS1 extending in an arc shape in the horizontal direction. The processing liquid discharged from the nozzle 30 lands on the upper surface of the substrate W held by the spin chuck 20 .

The cleaning unit 1 of the present embodiment is provided with two nozzles 60 and 65 in addition to the nozzle 30 described above. The nozzles 60 and 65 of this embodiment have the same 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 . Similarly, the nozzle 65 is configured by attaching a discharge head to the tip of a nozzle arm 67, and is arranged above the spin chuck 20 as indicated by an arrow AR69 by a nozzle base 68 connected to the base end of the nozzle arm 67. and 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 moved linearly by providing a linear drive.

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 formed to have a length such that the cover member 23 and the brim-like member 25 can be accommodated with an appropriate gap when 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. It is formed to a length that

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 . The folded portion 52c horizontally overlaps the tip of the upper end portion 47b of the first guide portion 47 when the inner cup 41 and the middle cup 42 are closest to each other.

The upper end portion 52b of the second guide portion 52 is formed 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 it can be lifted and lowered independently. 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 FFU 14 and flowing down in 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. As shown in FIG. The camera 70 is installed inside the chamber 10 above the partition plate 15 . The camera 70 includes, for example, a CCD, which is one of solid-state imaging devices, and an optical system such as an electronic shutter and a lens. By driving the nozzle base 33, the nozzle 30 moves between the processing section PS1 (dotted line position in FIG. 4) above the substrate W held by the spin chuck 20 and the waiting position (solid line position in FIG. 4) outside the processing cup 40. ) is reciprocated between The processing section PS1 is a section in which the cleaning process is performed by discharging the processing liquid from the nozzle 30 onto the upper surface of the substrate W held by the spin chuck 20 . Here, the processing section PS1 extends horizontally from a first end TE1 near one edge of the substrate W held by the spin chuck 20 to a second end TE2 near the opposite edge. It is an interval. The standby position is a position where the nozzles 30 stop discharging the treatment liquid and wait when the cleaning process is not performed. A standby pod that accommodates the ejection head 31 of the nozzle 30 may be provided at the standby position.

The camera 70 is installed at a position so that its imaging field of view includes at least the tips of the nozzles 30 in the processing section PS1, that is, the vicinity of the ejection head 31 is included. In this embodiment, as shown in FIG. 4, a camera 70 is installed at a position for capturing an image of the nozzles 30 in the processing section PS1 from above and in front. Therefore, the camera 70 can image an imaging area including the tip of the nozzle 30 in the processing section PS1. Similarly, camera 70 can image an imaging region including the tips of nozzles 60 and 65 in each processing interval. When the camera 70 is installed at the position shown in FIGS. 2 and 4, the nozzles 30 and 60 move laterally within the field of view of the camera 70. Therefore, the movement in the vicinity of each processing interval However, since the nozzle 65 moves in the depth direction within the imaging field of the camera 70, there is a possibility that the amount of movement in the vicinity of the processing section cannot be properly imaged. In this case, a camera for imaging the nozzle 65 may be provided separately from the camera 70 .

As shown in FIG. 3 , an illumination unit 71 is provided inside the chamber 10 at a position above the partition plate 15 . When the chamber 10 is a dark room, the control unit 9 controls the illumination unit 71 so that the illumination unit 71 illuminates the nozzles 30, 60, and 65 near the processing position when the camera 70 takes an image. good too.

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 stores 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, control software, data, and the like. It is configured with a magnetic disk or the like to store. Each operation mechanism of the substrate processing apparatus 100 is controlled by the control unit 9 by the CPU of the control unit 9 executing a predetermined processing program, and processing in the substrate processing apparatus 100 proceeds.

A reference image registration unit 90, a positional deviation detection unit 91, and a command transmission unit 92 shown in FIG. .

The reference image registration unit 90 registers, as a reference image RP, a captured image obtained by capturing an image of the nozzle 30 at the correct position. The positional deviation detection unit 91 detects a positional deviation of the nozzle 30 in the vertical direction or the horizontal direction at the determination position, which is the position to be determined. An image determination unit 910 and an image comparison unit 912 are included. Image determination unit 910 determines determination positions (for example, first end TE1, It is determined whether or not the image is at the second end TE2). Predetermined determination rules are described in detail later. The image comparison unit 912 performs pattern matching processing for comparing the actual image GP determined to be at the determination position by the image determination unit 910 and the reference image RP indicating the correct nozzle 30 position. This pattern matching process will also be described in detail later.

The command transmission unit 92 operates each element of the cleaning unit 1 by outputting a command (control information) according to a recipe describing various conditions for processing the substrate W. Specifically, the command transmission unit 92 outputs commands to the nozzles 30, 60, 65 to operate drive sources (motors) built in the nozzle bases 33, 63, 68. FIG. For example, when the command transmitting unit 92 transmits a command to move the nozzle 30 to the first end TE1 of the processing section PS1, the nozzle 30 moves from the waiting position to the first end TE1. Furthermore, when the command transmission unit 92 transmits a command to move the nozzle 30 to the second end TE2 of the processing section PS1, the nozzle 30 moves from the first end TE1 to the second end TE2. The ejection of the treatment liquid from the nozzles 30 may also be performed in response to command transmission from the command transmission section 92 .

The control unit 9 is composed of the RAM or magnetic disk described above, and includes a storage unit 94 that stores data of images captured by the camera 70, input values, and the like. A display unit 95 and an input unit 96 are connected to the control unit 9 . The display section 95 displays various information according to the image signal from the control section 9 . The input unit 96 is composed of input devices such as a keyboard and a mouse connected to the control unit 9 and receives input operations performed by the operator on the control unit 9 .

<Description of operation>
The normal processing of the substrate W in the substrate processing apparatus 100 includes a step of loading the substrate W to be processed received from the indexer 102 by the main transfer robot 103 into each cleaning processing unit 1, and carrying the substrate W into the cleaning processing unit 1. It includes a step of performing cleaning processing and a step of carrying out the processed substrate W from the cleaning processing unit 1 by the main transfer robot 103 and returning it to the indexer 102 . A typical cleaning process procedure for the substrate W in each cleaning unit 1 is as follows: chemical solution is supplied to the surface of the substrate W to perform a predetermined chemical solution treatment; Then, the substrate W is rotated at a high speed to shake off the pure water, thereby drying the substrate W. As shown in FIG.

When the cleaning unit 1 processes the substrate W, the spin chuck 20 holds the substrate W and the processing cup 40 moves up and down. When the cleaning processing unit 1 performs chemical processing, for example, only the outer cup 43 is raised, and the spin chuck 20 is positioned between the upper end 43 b of the outer cup 43 and the upper end 52 b of the second guide portion 52 of the inner cup 42 . An opening is formed surrounding the periphery of the held substrate W. As shown in FIG. In this state, the substrate W is rotated together with the spin chuck 20 , and the chemical liquid is supplied to the upper and lower surfaces of the substrate W from the nozzle 30 and the lower surface processing liquid nozzle 28 . The supplied chemical liquid flows along the upper and lower surfaces of the substrate W due to the centrifugal force caused by the rotation of the substrate W, and eventually scatters sideways from the edge portion of the substrate W. As shown in FIG. As a result, the substrate W is processed with the chemical solution. The chemical liquid scattered from the edge of the rotating substrate W is received by the upper end 43 b of the outer cup 43 , flows down along the inner surface of the outer cup 43 , and is recovered in the outer recovery groove 51 .

When the cleaning processing unit 1 performs the pure water rinsing process, for example, the inner cup 41 , the middle cup 42 and the outer cup 43 are all raised, and the periphery of the substrate W held by the spin chuck 20 is the first cup of the inner cup 41 . It is surrounded by the guide part 47 . In this state, the substrate W is rotated together with the spin chuck 20 , and pure water is supplied to the upper and lower surfaces of the substrate W from the nozzle 30 and the lower surface processing liquid nozzle 28 . The supplied pure water flows along the upper and lower surfaces of the substrate W due to the centrifugal force caused by the rotation of the substrate W, and eventually scatters sideways from the edges of the substrate W. As shown in FIG. As a result, the pure water rinsing process of the substrate W proceeds. The pure water scattered from the edge of the rotating substrate W flows down along the inner wall of the first guide portion 47 and is discharged from the disposal groove 49 . When the pure water is recovered through a path different from that of the chemical liquid, the middle cup 42 and the outer cup 43 are raised, and the upper end portion 52b of the second guide portion 52 of the middle cup 42 and the first guide portion of the inner cup 41 are moved. An opening surrounding the substrate W held by the spin chuck 20 may be formed between the upper end portion 47b of the portion 47 and the upper end portion 47b.

When the washing processing unit 1 performs the shake-off drying process, the inner cup 41, the middle cup 42, and the outer cup 43 all descend, and the upper end portion 47b of the first guide portion 47 of the inner cup 41 and the second guide portion of the middle cup 42 move downward. Both the upper end portion 52 b of the portion 52 and the upper end portion 43 b of the outer cup 43 are positioned below the substrate W held by the spin chuck 20 . In this state, the substrate W is rotated at high speed together with the spin chuck 20, water droplets attached to the substrate W are shaken off by centrifugal force, and a drying process is performed.

In this embodiment, when the processing liquid is discharged from the nozzles 30 onto the upper surface of the substrate W, the camera 70 images the nozzles 30 moving in the processing section PS1. Then, the positional deviation detection unit 91 detects the positional deviation of the nozzle 30 by comparing a series of captured images obtained by imaging with a reference image obtained in advance. The technique will be described in detail below. Although the technique for detecting the positional deviation of the nozzle 30 will be described below, it can also be applied to the other nozzles 60 and 65 .

FIG. 6 is a flow chart showing a procedure of advance preparation for detection processing by the misregistration detection unit 91. As shown in FIG. FIG. 7 is a flowchart showing the procedure of detection processing by the positional deviation detection unit 91. As shown in FIG. FIG. 6 shows a preparation procedure for positional deviation detection processing, and FIG. 7 shows a determination processing procedure performed when a substrate W to be processed is carried into the cleaning unit 1. As shown in FIG. . The preparation shown in FIG. 6 is performed prior to the actual processing of the substrate W to be processed, and may be performed, for example, when starting up the substrate processing apparatus 100 or during maintenance work. .

First, when teaching the nozzle 30, the nozzle 30 is moved to the teaching position (step S11). Teaching is a task of teaching the nozzle 30 to perform a proper operation, and corrects the stop position of the nozzle 30 in the processing section PS1 to a proper position (teaching position). Therefore, when the nozzle 30 is moved to the teaching position during teaching, the nozzle 30 is accurately moved in the proper processing section PS1. The appropriate processing section PS1 is a section in which the requested substrate processing can be performed by discharging the processing liquid from the nozzles 30 in the processing section PS1.

The processing section PS1 is a region defined above the substrate W held by the spin chuck 20, and is a moving range of the nozzle 30 extending in the horizontal direction. Both ends of the processing section PS1 are a first end TE1 and a second end TE2. The control unit 9 controls the nozzle base 33 to move the nozzle 30 from the first end TE1 to the second end TE2 in the processing section PS1.

When the nozzle 30 moves through the appropriate processing section PS1, the camera 70 continuously images the imaging area PA including the tip of the nozzle 30 (step S12). Continuous imaging refers to continuously imaging the imaging area PA at regular intervals. For example, the camera 70 takes continuous images at intervals of 33 milliseconds. As a result, 30 frames of photographed images are acquired per second. The camera 70 shoots moving images from the standby position until the nozzle 30 reaches the second end TE2 after reaching the first end TE1 of the processing section PS1.

FIG. 8 is a diagram showing an example of an image obtained by imaging the imaging area PA including the tips of the nozzles 30 in the processing section PS1 by the camera 70. As shown in FIG. The imaging area PA includes the tip of the nozzle 30 located in the middle of the processing section PS1 above the substrate W held by the spin chuck 20 . In the example shown in FIG. 8, the imaging area PA includes the substrate W, but this is not essential. For example, the substrate W may not be held by the spin chuck 20 during maintenance, and in such a case, imaging may be performed without the substrate W being included in the imaging area PA. As shown in FIG. 8, the shape of the nozzle 30 on the photographed image obtained by photographing the nozzle 30 moving in the processing section PS1 with the camera 70 fixed at a fixed position gradually changes. In the example shown in FIG. 8, the horizontal width of the nozzle 30 gradually increases from the first end TE1 and gradually decreases toward the second end TE2 from the middle. Note that the shape change of the nozzle 30 in the captured image is not limited to this.

Next, a reference image is registered from a plurality of photographed images obtained in step S12 (step S13). In step S12, the nozzle 30 is accurately moved from the first end TE1 to the second end TE2 of the appropriate processing section PS1 by teaching. Therefore, the photographed image obtained by the camera 70 in step S<b>12 becomes a reference image indicating the proper position of the nozzle 30 . In step S<b>13 , the reference image registration unit 90 registers part of the plurality of captured images in the storage unit 94 as the reference image RP for detecting the positional deviation of the nozzles 30 .

As shown in FIG. 8, the reference image RP is an image cut out from the photographed image so as to include the tip portion of the nozzle 30 . The clipping of the image may be performed by manually designating the area by the operator, or may be clipped automatically. In the latter case, for example, a portion (tip) of the nozzle 30 may be detected by image recognition, and a region including the tip of the nozzle 30 may be cut out based on that position. The clipped reference image RP is stored in the storage unit 94 together with position information in the imaging area PA. Normally, the cutting is performed manually in the chamber 10 which is set first. As for the other chambers 10 set after that, if the configuration between the chambers 10 is the same, the cutting information of the first set chamber 10 may be used as it is to cut out, or it may be adjusted as appropriate. Clipping may be performed.

In the present embodiment, the reference images RP to be registered include a first reference image RP1 when the nozzle 30 is at the first end TE1, a second reference image RP2 when the nozzle 30 is at the second end TE2, and a processing section PS1. (region between the first end TE1 and the second end TE2).

FIG. 9 is a diagram conceptually showing the registration processing of the reference image RP. The first registration processing shown in FIG. 9 is processing in which the reference image registration unit 90 automatically registers a plurality of reference images RP. In FIG. 9, the photographed image of the nozzle 30 shown on the upper side is an image obtained by continuously photographing the nozzle 30 moving from the first end TE1 toward the second end TE2 of the processing section PS1. As described with reference to FIG. 8, in captured images obtained by continuous imaging, the shape of the nozzle 30 changes while the nozzle 30 moves in the processing section PS1. In the registration process shown in FIG. 9, the reference image registration unit 90 registers the reference image RP in accordance with the shape change of the nozzle 30 .

First, it is assumed that the photographed image of the nozzle 30 at the first end TE1 is registered as the first reference image RP1. In this state, the reference image registration unit 90 sequentially compares the first reference image RP1 and the photographed images following the first reference image RP1, thereby performing pattern matching processing for calculating the degree of matching. As described above, since the shape of the nozzle 30 gradually changes on the captured image, the degree of matching with the first reference image RP1 gradually decreases. The reference image registration unit 90 registers the photographed image whose degree of matching is equal to or less than a predetermined threshold value as a new reference image RP. Specifically, the reference image registration unit 90 obtains the difference between the first reference image RP1 and the photographed image to be compared, and registers the photographed image as a new reference image RP when the difference exceeds a predetermined threshold. do. The reference image RP registered based on the comparison with the first reference image RP1 is the first intermediate reference image RPM1 corresponding to the first intermediate reference image RPM.

Subsequently, the reference image registration unit 90 compares the newly registered first intermediate reference image RPM1 with the photographed images that follow the photographed image corresponding to the first intermediate reference image RPM1. Then, the reference image registration unit 90 registers the photographed image whose degree of matching is equal to or less than a predetermined threshold as a second intermediate reference image RPM2 corresponding to the second intermediate reference image RPM. The reference image registration unit 90 registers a plurality of intermediate reference images RPM by repeatedly performing such registration processing until the target of the pattern matching processing is the photographed image of the second end TE2.

Returning to FIG. 6, when registration of a plurality of reference images RP is completed, the operator sets a threshold value for positional deviation determination (step S14). The threshold value set here is a parameter used in the later-described process for determining positional deviation of the nozzles 30 (step S25 shown in FIG. 7). The threshold is a threshold for deviation between the reference image RP registered in step S13 and the position of the nozzle 30 in the photographed image obtained by photographing the nozzle 30 to be determined. The lower the threshold set in step S14, the stricter the judgment criteria. That is, even if the amount of deviation from the correct position of the nozzle 30 to be determined is small, it is determined that the position deviation has occurred. The threshold set in step S14 is stored in the storage unit 94. FIG.

Advance preparation for the nozzle 30 is performed as described above. Preparations similar to those shown in steps S11 to S14 are also performed for the other nozzles 60 and 65 (step S15). If the nozzles other than the nozzle 30 are configured to discharge the processing liquid while being stopped at a certain processing position on the substrate W, in step S11, the nozzle is moved to that processing position, In step S12, it is preferable to photograph the nozzles stopped at the processing position. Then, in step S13, the captured image acquired in step S12 may be used as the reference image.

The advance preparation shown in FIG. 6 is sufficient if it is performed in advance when teaching is performed, and once performed, it does not need to be performed again until the teaching position is changed. It should be noted that the fixed lower surface treatment liquid nozzle 28 does not need to be prepared in advance as described above.

Next, a procedure for detection processing of positional deviation of the nozzles 30 will be described with reference to FIG. 7 . The main transport robot 103 carries the substrate W to be processed into the cleaning unit 1 (step S21). The loaded substrate W is held in a horizontal posture by the spin chuck 20 . At the same time, the processing cup 40 is moved up and down so as to reach a predetermined height position.

After the spin chuck 20 holds the new substrate W to be processed, the nozzle 30 starts moving from the standby position toward the first end TE1 of the processing section PS1 (step S22). The movement of the nozzle 30 is performed by the controller 9 controlling the nozzle base 33 according to a preset recipe. The recipe describes conditions for processing to be applied to the object in a predetermined data format. Specifically, it describes a processing procedure or processing details (processing time, temperature, pressure, or supply amount). After the nozzle 30 reaches the first end TE1 of the processing section PS1 and stops, the substrate W is rotated under the control of the control unit 9, and the discharge of the processing liquid from the nozzle 30 is started. Then, the nozzle 30 starts moving from the first end TE1 toward the second end TE2 of the processing section PS1 while discharging the processing liquid, and then stops at the second end TE2.

In step S22, the positional deviation detection unit 91 causes the camera 70 to start imaging in accordance with the movement of the nozzle 30 (step S23). The camera 70 continuously images the imaging area PA at intervals of 33 milliseconds, for example. That is, the camera 70 starts continuous imaging from the time when the spin chuck 20 holds a new substrate W to be processed and the nozzle 30 starts moving from the standby position toward the first end TE1 of the processing section PS1. . When the camera 70 starts continuous imaging, it is also the time when the nozzle 30 starts moving from the standby position, so the nozzle 30 has not reached the imaging area PA.

After the camera 70 starts continuous imaging, the positional deviation detector 91 identifies the actual image GP corresponding to the determination position (step S24). Specifically, the image determination unit 910 of the misregistration detection unit 91 selects a plurality of reference images registered in step S13 (FIG. 6) of preparation from among a plurality of actual images GP, which are images obtained in step S23. A real image GP corresponding to the determination position indicated by each image RP is specified.

FIG. 10 is a diagram conceptually showing how the actual image GP corresponding to the reference image RP is specified. In the example shown in FIG. 10, the actual image GP corresponding to the reference image RP is specified by comparing the reference image RP and the actual image GP. A known pattern matching technique may be applied to this comparison.

For example, among a large number of actual images GP, the actual image GP that has the highest degree of matching (the smallest difference) with the first reference image RP1 corresponding to the first end TE1 by pattern matching is one in which the nozzle 30 is positioned at the first end TE1. It is the first real image at a certain time. Also, the real image GP that has the highest matching degree with the second reference image RP2 corresponding to the second end TE2 is the second real image when the nozzle 30 is at the second end TE2. Each of the plurality of intermediate reference images RPM and each of the actual images GP having the highest degree of coincidence are obtained by the nozzles 30 at the center of the processing section PS1 (for example, the first and second intermediate reference images shown in FIG. 9). including RPM1 and RPM2).

<Stop judgment>
In the description of FIG. 10, as a determination rule, it is determined whether or not each actual image GP is an image corresponding to each determination position based on the degree of matching with the reference image RP. However, the judgment rule is not limited to this. For example, for the actual image GP corresponding to each position of the first end TE1 and the second end TE2 of the processing section PS1, it may be specified as a determination rule that the nozzle 30 has stopped.

Specifically, the stop determination of the movement of the nozzle 30 may be performed based on whether or not the difference between the two consecutive real images GP, GP is calculated and whether the difference is equal to or less than a predetermined threshold. The difference between two continuous real images GP, GP means a difference image showing the difference between one real image GP and the next real image GP. Calculating the difference means calculating the total sum of the absolute values of the gradation values of all the pixels in the difference image.

For example, the nozzle 30 temporarily stops at the first end TE1 after moving from the standby position toward the first end TE1. Between the continuous real images GP, GP while the nozzle 30 is moving toward the first end TE1, the image of the nozzle 30 tends to remain in the difference image between them. Therefore, the sum of the absolute values of the gradation values in the differential image is a relatively large value. On the other hand, since the positions of the nozzles 30 are the same between the continuous real images GP, GP after the nozzles 30 stop at the first end TE1, the nozzles 30 are removed from the differential images. Therefore, the sum of the absolute values of the gradation values in the differential image is a relatively small value. By appropriately setting the threshold based on such a principle, it is possible to easily and accurately detect that the nozzle 30 has stopped at the first end TE1. The image determination section 910 may also detect the stoppage of the nozzles 30 at the second end TE2 based on the same principle as the stoppage of the nozzles 30 at the first end TE1.

In order to prevent erroneous detection due to noise or the like, for example, the image determination unit 910 may calculate the difference between three or more continuous real images. Then, the image determination section 910 may determine that the nozzles 30 have stopped when all the obtained differences are equal to or less than the threshold.

The processes from step S21 to step S24 are processes that are executed each time a substrate W to be processed is carried into the cleaning unit 1 . That is, in the present embodiment, each time the spin chuck 20 holds the substrate W to be processed that has been loaded into the cleaning unit 1 and the nozzle 30 moves in the processing section PS1, each of the plurality of reference images RP is displayed. A corresponding real image is identified.

After step S24, the image comparison unit 912 of the misregistration detection unit 91 compares the plurality of reference images RP with the actual images corresponding to each of the reference images RP, and detects the misregistration of the nozzles 30 at each determination position. (step S25). The reference image RP is an image obtained by imaging the imaging area PA with the camera 70 when the nozzle 30 is accurately positioned at each determination position in the processing section PS1 during teaching. Further, the actual image specified in step S24 is obtained by imaging the imaging area PA with the camera 70 when the spin chuck 20 holds the substrate W to be processed and the nozzle 30 moves in the processing section PS1. It is a captured image corresponding to each reference image RP (that is, having a high degree of matching). Therefore, by comparing each reference image RP with the corresponding actual image, it is possible to determine whether or not the nozzle 30 has moved to an appropriate position above the substrate W, and whether or not the nozzle 30 has stopped at an appropriate position. can determine whether

Specifically, the image comparison unit 912 compares each of the plurality of reference images RP registered in step S13 with the corresponding real image GP identified in step S24. Then, the difference (positional deviation) between the coordinates of the nozzles 30 in both images is calculated. A known pattern matching technique may be applied to this comparison. If the positional deviation of the nozzles 30 calculated by pattern matching is equal to or greater than the threshold value determined in step S14, the image comparison unit 912 determines that the actual positions of the nozzles 30 at the determination positions are misaligned. do. When the positional deviation of the nozzles 30 is detected, the control unit 9 may perform predetermined abnormality handling processing. Examples of the abnormality handling process include issuing a warning (displaying a warning on the display unit 95, turning on a lamp (not shown), outputting a warning sound from a speaker (not shown), etc.) or stopping the operation of the cleaning unit 1. . If the calculated positional deviation of the nozzles 30 is smaller than the threshold value determined in step S14, it is determined that the actual positions of the nozzles 30 are not deviated. In addition, in step S25, a specific amount of positional deviation may be displayed on the display unit 95, for example, in addition to the determination of the positional deviation based on the threshold value.

Even if the shape of the nozzles 30 on the reference image RP and the shape of the nozzles 30 on the actual image GP match, the positions of the nozzles 30 obtained from the positional information of each image are shifted horizontally or vertically. may be In this embodiment, when the nozzles 30 are horizontally misaligned on the actual image GP, it is determined that there is a possibility that the nozzles 30 are horizontally misaligned. Further, when the nozzles 30 are vertically displaced on the actual image GP, it is determined that there is a possibility that the nozzles 30 are vertically displaced. A technique called “shape-based pattern matching” can be used to search for the nozzle 30 . Specifically, by searching the actual image GP for a region that matches the edge information of the nozzle 30 in the clipped reference image RP, and comparing the coordinate values of the found region with the coordinate values of the reference image RP, Determine whether misalignment has occurred.

The above is a description of the positional deviation detection process for the nozzle 30. However, the positional deviation can also be detected for the nozzles 60 and 65 other than the nozzle 30 in the same procedure as the flow shown in FIG. can be done. In the case where the nozzles other than the nozzle 30 are configured to eject the processing liquid while stopped at a certain processing position on the substrate W, as described above, in step S13 as a preparation, An image of the nozzle 30 correctly stopped at the processing position is registered as the reference image RP. Therefore, in step S24, the actual image GP corresponding to the processing position is specified as an image corresponding to the reference image RP by matching or stop determination, and in step S25, based on the comparison between the reference image RP and the actual image GP, , and other nozzle misalignments may be determined.

<effect>
As described above, the substrate processing apparatus 100 of the present embodiment can detect the positional deviation of the nozzles 30 that eject the processing liquid while moving in the processing section PS1. In particular, since positional deviation of the nozzle 30 at the first end TE1 and the second end TE2 can be detected, it can be inspected whether the nozzle 30 is correctly moving between both ends of the processing section PS1 to be moved. As a result, liquid processing using the moving nozzle 30 can be properly performed.

It can be determined whether or not the nozzle 30 moving in the middle of the processing section PS1 is moving to the correct position in the correct vertical direction. Therefore, it can be determined whether or not the processing liquid discharged from the nozzle 30 is supplied from the substrate W at an appropriate height. As a result, liquid processing using the moving nozzle 30 can be properly performed.

Positional deviation determination at each determination position of the nozzle 30 is performed based on comparison between the reference image RP and the actual image GP at each determination position. Therefore, even if the shape of the nozzle 30 changes due to movement in the processing section PS1, the actual image GP can be specified with high accuracy according to the shape of the nozzle 30 at each determination position. Therefore, it is possible to accurately detect the displacement of the nozzle 30 at each determination position.

<Position deviation detection using reference trajectory information>
In the above description, the misalignment of the nozzles 30 is detected by comparing the reference image RP and the actual image GP by pattern matching. However, positional deviation of the nozzle 30 may be detected using information on the trajectory (route) of the nozzle 30 moving in the processing section PS1.

FIG. 11 is a diagram conceptually showing the reference trajectory information ST1. The reference trajectory information ST1 is information indicating the path of the nozzle 30 when the nozzle 30 correctly moves from the first end TE1 to the second end TE2 of the processing section PS1. The reference trajectory information ST1 can be generated, for example, from a plurality of reference images RP.

The reference trajectory information ST1 may be generated by the positional deviation detector 91 specifying the position of the nozzle 30 from the reference image RP. Specifically, as shown in FIG. 11, the tip positions of the nozzles 30 are specified from the first and second reference images RP1 and RP2 and the plurality of intermediate reference images RPM, and these tip positions are The reference trajectory information ST1 may be generated by connecting them together by a known interpolation process. The reference trajectory information ST1 may be generated at an appropriate timing after step S13. Note that the reference trajectory information ST1 may be generated not only from the plurality of reference images RP registered in step S13, but also by using a series of captured images obtained by continuous imaging in step S12. In this case, the reference trajectory information ST1 indicating the precise trajectory of the nozzle 30 can be generated.

In step S25, when the positional deviation detection unit 91 detects the positional deviation of the nozzle 30 using the reference trajectory information ST1, the vertical position of the nozzle 30 is obtained from the actual image GP specified in step S24, and the reference trajectory information ST1 is obtained. The vertical positional deviation of the nozzle 30 is detected by comparing with the vertical position obtained from .

<Other Registration Processing of Reference Image RP>
In FIG. 9, the reference image registration unit 90 automatically registers a plurality of reference images RP by pattern matching processing. However, the reference image registration unit 90 may register the photographed image specified by the operator as the reference image RP.

FIG. 12 is a time chart showing how the nozzles 30 are continuously imaged. As described above, when the command transmission unit 92 outputs commands to the nozzles 30, 60, 65, the nozzle bases 33, 63, 68 are operated. At this time, the camera 70 continuously images the imaging area PA in response to command transmission from the command transmission unit 92 .

Information indicating any one of the nozzles 30, 60, and 65 and information indicating the destination positions of the ejection heads of the nozzles 30, 60, and 65 are recorded in the command. As shown in FIG. 12, photographed images of the moving nozzles 30, 60, and 65 are obtained by performing continuous imaging in response to the transmission of the commands C1 to C4.

In step S11 shown in FIG. 6, a command is transmitted to the nozzle base 33 to move the nozzle 30 from the standby position to the first end TE1. Further, a command is sent to the nozzle base 33 to move the nozzle 30 from the first end TE1 to the second end TE2. In addition, continuous imaging of the nozzles 30 in step S12 is performed in response to these command transmissions.

A series of captured images obtained by continuous imaging executed in response to a command is stored in association with the command that triggered the continuous imaging. For example, a series of captured images acquired in response to the command C1 are stored in the storage unit 94 in association with the command C1. Therefore, by designating the command C1, a series of captured images corresponding to the command C1 can be called.

FIG. 13 shows a registration screen W1 for registering the reference image RP. The registration screen W1 is a screen displayed on the display unit 95 by the reference image registration unit 90 . The registration screen W1 has an image display area WR2, a nozzle/position selection area WR4, a display control area WR6, and a registration determination button BT4.

The image display area WR2 is an area for continuously displaying a series of captured images in the order in which they were acquired. The nozzle/position selection region WR4 is a region that receives an operation of selecting any one of the plurality of nozzles 30, 60, 65 and an operation of selecting the destination of the selected nozzle.

The display control region WR6 is a region that receives an operation for controlling image display in the image display region WR2. A skip button BT2 is provided in the display control region WR6. The skip button BT2 accepts an operation of selecting a series of captured images displayed in the image display area WR2. Specifically, the operator selects a specific nozzle and the destination of the nozzle in the nozzle/position selection area WR4, and further operates the skip button BT2. Then, the reference image registration unit 90 displays in the image display area WR2 the first image among the series of captured images associated with the command corresponding to the selected nozzle and destination. In this manner, the operator can select a photographed image of a desired nozzle from among all photographed images photographed during one recipe by operating the nozzle/position selection area WR4 and the skip button BT2 in combination. It is displayed in the image display area WR2.

The registration determination button BT4 accepts an operation of registering the captured image displayed in the image display area WR2 as the reference image RP. The operator operates in the display control area WR6 to display a desired photographed image in the image display area WR2, and operates the registration determination button BT4 in this state. As a result, the captured image displayed in the image display area WR2 is registered as the reference image RP.

According to the registration screen W1, the operator can designate a command to be transmitted by the command transmission section 92 by operating the nozzle/position selection area WR4. As a result, a series of captured images associated with the command are selectively displayed in the image display area WR2. Therefore, the operator can efficiently display and check a series of photographed images showing the movement of the nozzles to be registered in the reference image RP. Therefore, the operator can efficiently register the reference image RP by operating the registration decision button BT4.

Although the nozzle 30 has one ejection head 31 in this embodiment, it may have a plurality of ejection heads 31 . In this case, the command transmission unit 92 transmits a command to the nozzle base 33, so that the target ejection head among the plurality of ejection heads moves to a predetermined position. This command may include not only information indicating the nozzles 30 but also information indicating any one of the plurality of ejection heads. Also, a command may be designated by accepting an operation for designating a specific ejection head in the nozzle/position selection area WR4.

<2. Second Embodiment>
Next, a second embodiment will be described. In the following description, elements having functions similar to those already described may be assigned the same reference numerals or reference numerals with additional alphabetic characters, and detailed description thereof may be omitted.

FIG. 14 is a diagram showing the control section 9A of the second embodiment. The controller 9A of the present embodiment differs from the controller 9 in that it includes a positional deviation detector 91A. The positional deviation detection section 91A has a function of detecting the positional deviation of the nozzles 30 similarly to the positional deviation detection section 91, but differs from the positional deviation detection section 91 in that it includes an image determination section 910A.

The image determination section 910A includes a feature vector calculation section 9102 and a classifier K2. The feature vector calculation unit 9102 calculates a feature vector, which is an array of multiple types of feature amounts, from each of the actual images GP acquired by the continuous imaging in step S23. The items of the feature amount are, for example, the sum of pixel values in grayscale of each real image GP, the sum of brightness, the standard deviation of pixel values, the standard deviation of brightness, and the like. The classifier K2 classifies the real image GP between classes based on the feature vectors calculated by the feature vector calculation unit 9102 . Here, multiple classes are defined corresponding to different positions of the nozzle 30 on the substrate W. FIG.

More specifically, each determination position of the nozzle 30 corresponding to each reference image RP registered by the reference image registration unit 90 is defined as a class. For example, two classes corresponding to the first end TE1 and the second end TE2 are defined. Also, a plurality of classes corresponding to different determination positions in the middle of the processing section PS1 are defined.

Like the image determination unit 910, the image determination unit 910A performs image determination processing in step S24 shown in FIG. Specifically, when a certain actual image GP is classified into a specific class by the classifier K2, the image determination unit 910A determines that the actual image GP is an image at the determination position corresponding to the specific class. do. For example, when the classifier K2 classifies the actual image GP into a class corresponding to the first end TE1, the image determination unit 910A determines that the actual image GP is an image when the nozzle 30 is positioned at the first end TE1. do.

As shown in FIG. 14, a communication section 97 is connected to the control section 9A. The communication section 97 is provided for data communication between the control section 9A and the server 8 . The substrate processing apparatus 100, communication unit 97 and server 8 constitute a substrate processing system. The classifier K2 described above is generated by the server 8 through machine learning, and is provided from the server 8 to the controller 9A.

The server 8 has a machine learning unit 82 . The machine learning unit 82 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 adopted. Further, the teacher data used for machine learning is the feature vector of the photographed image obtained by photographing the nozzle 30 at a specific determination position with the camera 70, and the class which is information indicating the class corresponding to the specific determination position. including labels. Teacher data is prepared for each class corresponding to each of a plurality of determination positions.

It is not essential that the substrate processing apparatus 100 is connected to the server 8 . For example, the substrate processing apparatus 100 may include the machine learning section 82 . In this case, the classifier K2 can be generated in the substrate processing apparatus 100 .

The classifier K2 determines the actual image GP when the nozzle 30 is at the determination position. Similarly, the other nozzles 60 and 65 are also classified into classes corresponding to different positions. A classifier may be prepared and the real image GP at the determination position may be specified by the classifier.

FIG. 15 is a diagram conceptually showing the classifier K2. A classifier K2 shown in FIG. 15 is constructed by a neural network NN1. The neural network NN1 has an input layer, an intermediate layer, and an output layer, and the input layer receives a plurality of types of feature amounts of an image to be classified (actual image GP to be inspected). A plurality of classes are defined for each different determination position of the nozzle 30, and the actual image GP is classified into one of the classes in the output layer. Note that when the actual image GP is not classified into any class, the classifier K2 outputs that classification is not possible. Although the classifier K2 has one hidden layer in FIG. 15, it may have multiple hidden layers.

In the classifier K2 shown in FIG. 15, a feature vector is calculated from the entire image, which is the imaging area PA of the camera 70, and the classifier K2 performs classification based on the feature vector. However, the classifier K2 may be generated by the machine learning unit 82 performing learning using an image obtained by cutting a portion of the entire image so as to include the tip of the nozzle 30 as teacher data.

As described above, according to the present embodiment, the real image GP corresponding to the determination position can be accurately identified by classification by the classifier K2 generated by machine learning. Therefore, by comparing the reference image RP and the actual image GP, it is possible to appropriately detect the displacement of the nozzle 30 at the determination position.

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 appropriately combined or omitted as long as they do not contradict each other.

REFERENCE SIGNS LIST 100 substrate processing apparatus 1 cleaning processing unit 10 chamber 20 spin chuck 21 spin base 21a holding surface 22 spin motor 30, 60, 65 nozzle 31 ejection head 70 camera 71 lighting unit 8 server 82 machine learning unit 9, 9A control unit 90 reference image Registration unit 91, 91A Positional deviation detection unit 910, 910A Image determination unit 9102 Feature vector calculation unit 912 Image comparison unit 92 Command transmission unit 95 Display unit 96 Input unit 97 Communication unit C1-C4 Command (control information)
GP Actual image K2 Classifier PA Imaging area PS1 Processing section RP Reference image RP1 First reference image RP2 Second reference image RPM Intermediate reference image RPM1 First intermediate reference image RPM2 Second intermediate reference image ST1 Reference trajectory information TE1 First End TE2 Second end W Substrate W1 Registration screen

Claims (13)

A substrate processing method for processing a substrate,
(a) moving the nozzle within a predetermined horizontally extending treatment zone;
(b) capturing an image of the nozzle moving in the processing section by the step (a);
(c) registering, as first and second reference images, photographed images obtained when the nozzle is located at the first end and the second end, which are both ends of the processing section, in the step (b);
(d) moving the nozzle within the treatment zone;
(e) imaging the nozzle moving in the processing section by the step (d);
(f) an image determination step of determining whether or not the plurality of captured images obtained in step (e) correspond to the first end and the second end based on a predetermined determination rule;
(g) comparing said first and said second reference images with the first and second actual images determined by said step (f) to correspond to said first edge and said second edge, respectively; a step of detecting misalignment of the nozzles arranged at each end of the processing section in step (d);
A method of processing a substrate, comprising: The substrate processing method of claim 1,
(h) after step (c) and before step (d), a step of holding a substrate to be processed on a substrate holder;
A substrate processing method further comprising: The substrate processing method according to claim 1 or claim 2,
The step (d) is
(d1) moving the nozzle from a position closer to the first end toward the second end;
including
The step (f) is
(f1) determining whether or not the images correspond to the first end and the second end based on the difference between successive captured images;
A method of processing a substrate, comprising: The substrate processing method according to any one of claims 1 to 3,
The step (c) is
(c1) registering an intermediate reference image obtained by imaging the nozzle moving in the middle of the processing section in step (b);
including
The step (g) is
(g1) performing the processing in step (d) based on a comparison between the intermediate reference image and an intermediate real image obtained by imaging the nozzle moving in the middle of the processing section in step (e); detecting a positional deviation of the nozzle moving in the middle of the interval;
A method of processing a substrate, comprising: The substrate processing method of claim 4,
The step (g) is
(g2) A substrate processing method including the step of detecting positional deviation of the nozzle in a vertical direction based on the intermediate reference image and the intermediate real image. The substrate processing method according to claim 4 or 5,
(i) generating reference trajectory information indicating a trajectory of the nozzle moving in the processing section from the plurality of intermediate reference images registered in step (c1);
further comprising
The step (g) is
(g3) detecting displacement of the nozzle in the vertical direction based on the intermediate real image and the reference trajectory information;
A method of processing a substrate, comprising: The substrate processing method according to any one of claims 4 to 6,
The step (c1) is
(c11) registering, as a first intermediate reference image, one of a plurality of photographed images obtained by photographing the nozzle moving in the middle of the processing section in step (b);
(c12) After step (c11), photographing an image following the first intermediate reference image among the plurality of photographed images, the degree of matching with the first intermediate reference image being equal to or less than a predetermined threshold. registering the image as a second intermediate reference image;
A method of processing a substrate, comprising: The substrate processing method according to any one of claims 1 to 7,
The step (a) is
(a1) sending a control signal to a nozzle moving unit to move the nozzle from the first end to the second end by the control unit;
including
The step (b) is
(b1) imaging the nozzle in response to transmission of the control signal to obtain a plurality of captured images;
A method of processing a substrate, comprising: The substrate processing method of claim 8,
The step (b) is
(b2) a step of correlating and recording control information indicated by the control signal with a plurality of captured images acquired by imaging according to the control signal;
A substrate processing method further comprising: The substrate processing method of claim 9,
The step (c) is
(c2) a step of displaying a series of captured images obtained in step (b) on a display unit in the order in which they were obtained;
including
The step (c2) is
(c21) designating the control information;
(c22) displaying, on the display unit, a photographed image corresponding to the control information specified in step (c21);
A method of processing a substrate, comprising: A substrate processing apparatus for processing a substrate,
a substrate holder that holds the substrate in a horizontal posture;
a nozzle for supplying a processing liquid to the substrate held by the substrate holding part;
a nozzle moving unit that moves the nozzle within a predetermined treatment section extending in the horizontal direction;
a camera that acquires a captured image by capturing an image of the nozzle moving within the processing section;
a reference image registration unit that registers first and second reference images obtained by imaging the nozzles at first and second ends, which are both ends of the processing section, with the camera;
a misalignment detection unit that detects misalignment of the nozzles at the first end and the second end;
with
The positional deviation detection unit is
Based on a predetermined determination rule, it is determined whether or not the actual image obtained by imaging the nozzle moving in the processing section is an image corresponding to each of the first end and the second end. an image determination unit;
an image comparison unit that compares the first and second reference images with the first and second real images determined by the image determination unit to correspond to the first edge and the second edge, respectively;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 11,
The image determination unit
a feature vector calculation unit that extracts a plurality of types of feature vectors from each of the plurality of captured images;
a classifier that classifies each of the plurality of captured images into classes corresponding to different positions of the nozzle according to the plurality of types of feature vectors;
including
The substrate processing apparatus, wherein the plurality of classes includes classes corresponding to each of the first end and the second end. A substrate processing system including a substrate processing apparatus that processes a substrate and a server that performs data communication with the substrate processing apparatus,
The substrate processing apparatus is
a substrate holder that holds the substrate in a horizontal posture;
a nozzle for supplying a processing liquid to the substrate held by the substrate holding part;
a nozzle moving unit that moves the nozzle within a predetermined treatment section extending in the horizontal direction;
a camera that acquires a captured image by capturing an image of the nozzle moving within the processing section;
a reference image registration unit that registers first and second reference images obtained by imaging the nozzles at first and second ends, which are both ends of the processing section, with the camera;
a misalignment detection unit that detects misalignment of the nozzles at the first end and the second end;
a communication unit that performs data communication with the server;
with
The positional deviation detection unit is
Based on a predetermined determination rule, it is determined whether or not the actual image obtained by imaging the nozzle moving in the processing section is an image corresponding to each of the first end and the second end. an image determination unit;
an image comparison unit that compares the first and second reference images with the first and second real images determined by the image determination unit to correspond to the first edge and the second edge, respectively;
with
The image determination unit
a feature vector calculation unit that extracts a plurality of types of feature vectors from the captured image;
a classifier that classifies the plurality of captured images into a plurality of classes corresponding to different positions of the nozzle based on the plurality of types of feature vectors;
including
the plurality of classes includes a class of images corresponding to each of the first end and the second end;
The server includes a machine learning unit that generates the classifier by machine learning using the plurality of captured images taught by one of the plurality of classes as teacher data,
The substrate processing system, wherein the classifier is provided from the server to the substrate processing apparatus.

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