Substrate processing system, substrate processor, and method for visualization

Abstract

To provide a system which can easily visualize the distribution of flow of fluid in a substrate processor.SOLUTION: A substrate processing system 1 includes: a substrate processor 50 having a storage space A1 for storing a substrate W; a camera 81 directed to the storage space A1; a pattern 82 provided to spread in the field of vision of the camera 81, the pattern being taken by the camera 81 through the storage space A1; and a map generation unit 211 for generating map data representing the distribution of fluid in the storage space A1 on the basis of change of the image of the pattern 82 taken by the camera 81.SELECTED DRAWING: Figure 4

Description

Technical Field

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

Background Art

[0002] Patent Document 1 discloses a method for visualizing an air flow, in which a tracer that moves by the air flow is mixed into the air flow to be visualized, and a beam-shaped laser beam including wavelengths in a specific visible light range is repeatedly scanned and irradiated onto the air flow, and scattered light generated at that time is recognized through an optical filter having a relatively high transmittance only in the oscillation wavelength range of the laser beam.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides a system capable of easily visualizing the distribution of fluid flow in a substrate processing apparatus.

Means for Solving the Problems

[0005] A substrate processing system according to an aspect of the present disclosure includes a substrate processing apparatus having an accommodation space for accommodating a substrate, a camera directed toward the accommodation space, a pattern provided so as to spread within the field of view of the camera and photographed by the camera through the accommodation space, and a map generation unit that generates map data representing the distribution of fluid flow in the accommodation space based on changes in an image of the pattern photographed by the camera.

Effects of the Invention

[0006] According to the present disclosure, a system capable of easily visualizing the distribution of fluid flow in a substrate processing apparatus can be provided.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Embodiments for Carrying Out the Invention

[0008] Hereinafter, a wafer processing system as a substrate processing apparatus according to the present embodiment will be described with reference to the drawings. In this specification, elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant descriptions are omitted.

[0009] 〔Wafer Processing System〕 First, the configuration of the wafer processing system according to the present embodiment will be described. FIGS. 1 and 2 are a plan view and a front view schematically showing the outline of the configuration of the wafer processing system 1, respectively. In the present embodiment, a case where the wafer processing system 1 is a photolithography processing system that performs a resist film formation process and a development process on the wafer W will be described as an example.

[0010] As shown in FIG. 1, the wafer processing system 1 includes a cassette station 2 into which a cassette C containing a plurality of wafers W is loaded and unloaded, and a processing station 3 including a plurality of various processing apparatuses that perform predetermined processing on the wafers W. The wafer processing system 1 has a configuration in which the cassette station 2, the processing station 3, and an interface station 4 that transfers the wafer W between the processing station 3 and an exposure apparatus (not shown) adjacent to the opposite side of the processing station 3 are integrally connected. Note that, as shown in FIG. 1, two processing stations 3 are provided between the cassette station 2 and the interface station 4, but one or three or more processing stations 3 may be provided.

[0011] The cassette station 2 is provided with a plurality of cassette mounting tables 21, wafer transfer devices 22 and 23. The cassette station 2 transfers the wafer W between the cassette C placed on the mounting table 12 and the processing station 3 by the wafer transfer device 22 or 23. For this purpose, the wafer transfer devices 22 and 23 are each provided with a drive mechanism in a direction such as the X direction, the Y direction, the vertical direction, and the vertical axis rotation direction (θ direction) as needed, and may be provided with drive mechanisms in all directions. At least one of the wafer transfer devices 22 and 23 can transfer wafers between the cassette C and the wafer W, and can also transfer the wafer W to and from the processing station 3. Note that the transfer operation of the wafer W to and from the processing station 3 means, for example, transferring the wafer W between the third block G3 having a transfer device accessible by the wafer transfer device 33 in the processing station 3 described later. The third block G3 may include a plurality of transfer devices (not shown) arranged in the vertical direction.

[0012] Note that the cassette station 2 may be provided with an inspection device (not shown) for inspecting the wafer W at a position accessible by either of the wafer transfer devices 22 and 23.

[0013] The processing station 3 is provided with a plurality of blocks, for example, three blocks G1, G2, and G4 of the first, second, and fourth. Also, as shown in FIG. 2, a plurality of layers 31 including the first and second blocks G1 and G2 are stacked in the vertical direction. For example, the first block G1 is provided on the front side (negative X direction side in FIG. 1) of the processing station 3, and the second block G2 is provided on the back side (positive X direction side in FIG. 1) of the processing station 3. The fourth block G4 is provided on the interface station 4 side (positive Y direction side in FIG. 1) of the processing station 3 or at the connection portion with another adjacent processing station 3. The fourth block G4 may include a plurality of transfer devices arranged in the vertical direction. Also, the aforementioned third block G3 may be provided in the processing station 3.

[0014] A plurality of processing devices, for example, a patterning film forming device and a development processing device (both not shown) are arranged in the first block G1. As the patterning film forming device, for example, in addition to a resist film forming device, an antireflection film forming device can be included. For example, a plurality of processing devices are arranged side by side in the horizontal direction. Note that the number, arrangement, and type of these processing devices can be arbitrarily selected.

[0015] In these patterning film forming apparatuses and developing apparatuses, for example, a predetermined processing liquid is supplied onto the wafer W, or a predetermined gas is supplied. In this way, in the patterning film forming apparatus, formation of a resist film used as a mask when forming a pattern of the lower layer side film, and formation of an antireflection film or the like for efficiently performing light irradiation processing such as exposure processing are carried out. On the other hand, in the developing apparatus, a part of the exposed resist film is removed to form an uneven shape as the mask.

[0016] For example, in the second block G2, heat treatment apparatuses (not shown) for performing heat treatment such as heating and cooling of the wafer W are arranged side by side in the vertical direction and the horizontal direction. Also in the second block G2, although not shown in any figure, a hydrophobization treatment apparatus for performing hydrophobization treatment to enhance the adhesion between the resist liquid and the wafer W, and a peripheral exposure apparatus for exposing the outer peripheral portion of the wafer W are arranged side by side in the vertical direction (Z direction in FIG. 2) and the horizontal direction. The number and arrangement of these heat treatment apparatuses, hydrophobization treatment apparatuses, and peripheral exposure apparatuses can also be arbitrarily selected.

[0017] As shown in FIG. 1, a wafer transfer region 32 is formed in the region sandwiched between the first block G1 and the second block G2 in plan view. In the wafer transfer region 32, for example, a wafer transfer apparatus 33 is arranged.

[0018] The wafer transfer apparatus 33 has, for example, a transfer arm that is movable in the X direction, Y direction, θ direction, and vertical direction. The wafer transfer apparatus 33 moves within the wafer transfer region 32 and can transfer the wafer W to predetermined apparatuses within the surrounding first block G1, second block G2, third block G3, and fourth block G4. When there are a plurality of processing stations 3 as shown in FIG. 1, the wafer transfer apparatus 33 provided in the processing station 3 located on the interface station 4 side can transfer the wafer W to predetermined apparatuses within the fifth block G5 described later in addition to the first, second, and fourth blocks G1, G2, and G4.

[0019] For example, a plurality of wafer transfer devices 33 are arranged vertically. One wafer transfer device 33 can transfer the wafer W to a predetermined device located at the height of a plurality of upper layers 31 (see FIG. 2) among a plurality of layers 31 stacked vertically. For a predetermined device located at the height of a plurality of layers 31 positioned below those layers 31, another wafer transfer device 33 can transfer the wafer W. A plurality of wafer transfer regions 32 are provided to enable such transfer of the wafer W. Note that the number of wafer transfer devices 33 and the number of layers 31 corresponding to one wafer transfer device 33, such as providing one wafer transfer device 33 for each layer 31, can be arbitrarily selected.

[0020] Also, a shuttle transfer device (not shown) may be provided in the wafer transfer region 32 or the first block G1 or the second block G2. The shuttle transfer device linearly transfers the wafer W between a space adjacent to one side of the processing station 3 and another space adjacent to the opposite side.

[0021] The interface station 4 is provided with a fifth block G5 including a plurality of transfer devices, and wafer transfer devices 41 and 42. The interface station 4 transfers the wafer W using the wafer transfer device 41 or 42 between the fifth block G5 where the wafer W is transferred by the wafer transfer device 33 and the exposure device. For this purpose, the wafer transfer devices 41 and 42 are each provided with a drive mechanism in directions such as the X direction, Y direction, vertical direction, and rotation around the vertical axis (θ direction) as needed, and may be provided with drive mechanisms in all directions. At least one of the wafer transfer devices 41 and 42 can support the wafer W and transfer the wafer W between the transfer device in the fifth block G5 and the exposure device.

[0022] A cleaning device for cleaning the surface of the wafer W and the aforementioned peripheral exposure device may be provided within the interface station 4 at a position accessible by either of the wafer transfer devices 41 and 42.

[0023] The inspection device may be provided in the cassette station 2 as described above, but may also be provided at accessible positions inside the processing station 3 and the interface station 4, respectively, with any of the transfer arms (33, 41, 42 in FIG. 1 or FIG. 2).

[0024] The above wafer processing system 1 is provided with a control device 100. The control device 100 is, for example, a computer and has a program storage unit (not shown). The program storage unit stores a program for controlling the processing of the wafer W in the wafer processing system 1. Further, the program storage unit also stores a program for controlling the operations of the drive systems of the above various processing devices and transfer devices to realize the wafer processing in the wafer processing system 1. Note that the above program may be recorded on a computer-readable storage medium H and installed from the storage medium H into the control device 100.

[0025] 〔Operation of Wafer Processing System〕 The wafer processing system 1 is configured as described above. Next, an example of wafer processing performed using the wafer processing system 1 configured as described above will be described.

[0026] First, a cassette C containing a plurality of wafers W is carried into the cassette station 2 of the wafer processing system 1 and placed on the cassette mounting table 21. Next, each wafer W in the cassette C is sequentially taken out by the wafer transfer device 22 or 23 and transferred to the transfer device of the third block G3.

[0027] The wafer W conveyed to the transfer device of the third block G3 is supported by the wafer transfer device 33 and conveyed to the hydrophobic treatment device provided in the second block G2, where the hydrophobic treatment is performed. Next, it is conveyed to the resist film forming device by the wafer transfer device 33, and a resist film is formed on the wafer W. After that, the wafer W is conveyed to the heat treatment device for pre-baking, and then conveyed to the transfer device of the fifth block G5. When there are multiple processing stations 3 as shown in FIGS. 1 and 2, the wafer W is placed once in the transfer device of the fourth block G4 before being conveyed to the transfer device of the fifth block G5, and then transferred between the multiple wafer transfer devices 33. Also, the wafer W may be conveyed to the peripheral exposure device by the wafer transfer device 33 as needed, and the exposure process may be performed on the peripheral portion of the wafer W.

[0028] The wafer W conveyed to the transfer device of the fifth block G5 is conveyed to the exposure device by the wafer transfer devices 41 and 42 and subjected to an exposure process in a predetermined pattern. Note that the cleaning device may clean the wafer W before the exposure process.

[0029] The exposed wafer W is conveyed to the transfer device of the fifth block G5 by the wafer transfer devices 41 and 42. After that, the wafer W is conveyed to the heat treatment device by the wafer transfer device 33 for post-exposure baking.

[0030] The wafer W subjected to post-exposure baking is conveyed to the development processing device by the wafer transfer device 33 and developed. After the development is completed, the wafer W is conveyed to the heat treatment device 40 by the wafer transfer device 33 for post-bake processing.

[0031] After that, the wafer W is conveyed to the transfer device of the third block G3 by the wafer transfer device 33, and conveyed to the cassette C on the predetermined cassette mounting table 21 by the wafer transfer device 22 or 23 of the cassette station 2. Thus, a series of photolithography processes are completed.

[0032] Note that the wafer processing system in the present disclosure is not limited to the configurations and operations described above. For example, in the above-described embodiments, it has been described that the wafer W is transferred between the interface station 4 and the exposure apparatus, but it does not necessarily have to be directly connected to the exposure apparatus. In that case, for example, after the wafer W is transported from the cassette station 2 to the processing station 3 and the necessary processing is performed, it is transported back to the cassette station 2 for external unloading. Also, among the processing apparatuses listed, those that are not necessary may not be provided, or the processing in those apparatuses may not be performed.

[0033] 〔Substrate Processing Apparatus〕 FIG. 3 is a plan view illustrating a substrate processing apparatus 50, and FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 3. The substrate processing apparatus 50 is included in the wafer processing system 1. For example, the substrate processing apparatus 50 includes the above-described patterning film forming apparatus 50A.

[0034] The patterning film forming apparatus 50A includes a chamber 60A, a rotation holding unit 71, a cup 72, and a liquid supply unit 73. The chamber 60A has an accommodation space A1 for accommodating the wafer W (a semiconductor wafer: an example of a substrate). For example, the chamber 60A includes a top plate 61, a bottom plate 62, a peripheral wall 63, a shutter 66, and an exhaust port 67. The top plate 61 extends horizontally above the accommodation space A1. The bottom plate 62 extends horizontally below the accommodation space A1. The peripheral wall 63 surrounds the accommodation space A1 between the top plate 61 and the bottom plate 62 and connects the top plate 61 and the bottom plate 62.

[0035] The peripheral wall 63 includes a partition wall 64 that partitions the accommodation space A1 and the peripheral space PA1. For example, the peripheral wall 63 includes a pair of partition walls 64A and 64B, and a pair of partition walls 64C and 64D. The partition walls 64A and 64B face each other with the accommodation space A1 therebetween. The pair of partition walls 64C and 64D face each other with the accommodation space A1 therebetween in a direction intersecting (for example, orthogonal) to the direction in which the partition walls 64A and 64B sandwich the accommodation space A1.

[0036] In the partition wall 64, an opening 65 through which the wafer W passes is formed when the wafer W is carried into the accommodation space A1 from the peripheral space PA1 and carried out from the accommodation space A1 to the peripheral space PA1. For example, the opening 65 is formed in the partition wall 64A. The shutter 66 is driven by, for example, an electric motor or the like and moves up and down to open and close the opening 65.

[0037] The exhaust port 67 opens into the accommodation space A1 and sends out the gas (an example of a fluid) in the accommodation space A1 to the outside of the chamber 60A. Thereby, the accommodation space A1 is ventilated, and the vaporized substances and the like generated during the processing of the wafer W are discharged to the outside of the chamber 60A.

[0038] The rotary holding unit 71 supports and adsorbs the horizontally arranged wafer W from below and is driven by an electric motor or the like to rotate about a vertical axis. The liquid supply unit 73 supplies a processing liquid to the wafer W accommodated in the accommodation space A1. Examples of the processing liquid include, for example, a film-forming liquid for forming a patterning film. Examples of the film-forming wall include, for example, a resist liquid containing a negative-type or positive-type resist material.

[0039] For example, the liquid supply unit 73 includes a nozzle 74 and a nozzle transfer device 75. The nozzle 74 opens downward and is disposed above the rotary holding unit 71, and discharges the processing liquid toward the wafer W held by the rotary holding unit 71. The nozzle transfer device 75 is driven by an electric motor or the like and moves the nozzle 74 along the horizontal direction. The nozzle transfer device 75 may be configured to move the nozzle 74 up and down in addition to moving it in the horizontal direction.

[0040] The cup 72 opens upward and accommodates the wafer W held by the rotary holding unit 71. The cup 72 collects the processing liquid shaken off from above the wafer W, for example, by the rotation of the rotary holding unit 71 and the wafer W. The cup 72 has an exhaust port 76. The exhaust port 76 opens into the cup 72 and sends out the gas in the cup 72 to the outside of the cup 72. Thereby, the inside of the cup 72 is ventilated, and the vaporized substances and the like generated during the processing of the wafer W are discharged to the outside of the cup 72. For example, the exhaust port 76 opens at the bottom of the cup 72.

[0041] According to the exhaust port 67 and the exhaust port 76, a gas flow (an example of a fluid flow) is formed in the accommodation space A1. For example, when the gas in the accommodation space A1 is sent out of the chamber 60A through the exhaust port 67, a gas flow that enters the accommodation space A1 from the opening 65 and exits the chamber 60A through the exhaust port 67 is formed in the accommodation space A1. When the gas in the cup 72 is sent out of the cup 72 through the exhaust port 76, a gas flow that enters the cup 72 from above and exits the cup 72 through the exhaust port 76 is formed in the accommodation space A1. The fluid flow generated in the accommodation space A1 can affect the processing of the wafer W. For example, the gas flow in the accommodation space A1 of the patterning film forming apparatus 50A can affect the uniformity of the film thickness of the patterning film formed on the wafer W and the like.

[0042] In order to control the influence caused by the fluid flow, it is necessary to visualize the distribution of the fluid flow. Therefore, the substrate processing apparatus 50 further includes a camera 81 and a pattern 82. The camera 81 is directed toward the accommodation space A1 in the chamber 60A.

[0043] The camera 81 has, for example, an image sensor such as a charge coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS), and an optical system that forms an image of light from the field of view direction on the image sensor. The image sensor includes a plurality of pixels arranged in a matrix.

[0044] The pattern 82 is provided so as to at least extend within the field of view of the camera 81 and is photographed by the camera 81 through the accommodation space A1. The pattern 82 changes the image captured by the camera 81 by the schlieren effect. For example, the pattern 82 changes the image captured by the camera 81 according to the change in the refractive index of the fluid in the accommodation space A1.

[0045] For example, when the refractive index of the fluid in the accommodation space A1 changes, the incident position of light from the pattern 82 to the camera 81 changes. Therefore, the shape or the like of the pattern 82 photographed by the camera 81 may partially change. If the pattern 82 does not exist, no change in the shape or the like of the pattern 82 occurs in the image photographed by the camera 81. Therefore, when the pattern 82 exists, the change in the image caused by the change in the refractive index of the fluid in the accommodation space A1 can be considered to be caused by the pattern 82.

[0046] The refractive index of the fluid correlates with the density of the fluid. Since the density of the fluid changes due to the fluid flow, the refractive index of the fluid in the accommodation space A1 also correlates with the fluid flow in the accommodation space A1. For example, at a location in the accommodation space A1 where there is a fluid flow (hereinafter referred to as a "flowing location"), the refractive index of the fluid changes due to the fluid flow. On the other hand, at a location in the accommodation space A1 where there is no fluid flow (hereinafter referred to as a "stationary location"), the refractive index of the fluid does not change. Therefore, among the pattern 82, the imaging position of the portion incident on the camera 81 passing through the stationary location does not change, while the imaging position of the portion incident on the camera 81 passing through the flowing location changes. As a result, in the image photographed by the camera 81, the distribution of the fluid flow in the accommodation space A1 is visualized as a partial fluctuation in the shape or the like of the pattern 82. In this way, due to the Schlieren effect, the fluctuation of the image caused by the fluid flow is sharpened by the pattern 82, so that the distribution of the fluid flow in the accommodation space A1 can be clearly visualized.

[0047] As illustrated in FIG. 5, the pattern 82 may include a plurality of motifs 83 arranged so as to be dispersed within the field of view of the camera 81. The fluctuation of the image due to the Schlieren effect is further sharpened by the plurality of motifs 83. Therefore, the distribution of the fluid flow in the substrate processing apparatus 50 can be visualized more clearly.

[0048] For example, a plurality of motifs 83 are two-dimensionally arranged. Examples of the two-dimensional arrangement include, but are not limited to, a matrix arrangement in which the motifs are arranged in row and column directions perpendicular to each other. For example, the plurality of motifs 83 may be arranged in a staggered grid pattern or a honeycomb pattern.

[0049] The motif 83 is a constituent unit of the pattern 82. There are no particular restrictions on the shape and size of the motif 83. For example, the motif 83 may be circular, rectangular, or polygonal such as hexagonal. The plurality of motifs 83 may include two or more motifs 83 that are different from each other in at least one of shape, size, and color. The shapes, sizes, and colors of the plurality of motifs 83 may be the same as each other. The plurality of motifs 83 may be in contact with each other or may be separated from each other.

[0050] The plurality of motifs 83 may be arranged at a constant pitch or may be arranged at a non-constant pitch. The pitch is, for example, the center-to-center distance. For example, when the plurality of motifs 83 are arranged in a matrix, the pitch of the plurality of motifs 83 in the row direction may be constant, and the pitch of the plurality of motifs 83 in the column direction may be constant.

[0051] The plurality of motifs 83 and the spaces between the plurality of motifs 83 may be distinguished by different colors from each other. For example, the plurality of motifs 83 may be white, and the spaces between the plurality of motifs 83 may be black. Conversely, the plurality of motifs 83 may be black, and the spaces between the plurality of motifs 83 may be white.

[0052] In the pattern 82 illustrated in FIG. 5, a plurality of motifs 83 having the same shape, size, and color are arranged in a matrix at a constant pitch P1. Each of the plurality of motifs 83 is rectangular and is partitioned from each other by grid-like lines 84. The plurality of motifs 83 and the lines 84 between the plurality of motifs 83 are distinguished by different colors from each other. For example, the plurality of motifs 83 are white, and the lines 84 are black.

[0053] Pattern 82 may be formed by unevenness on the surface. For example, a plurality of motifs 83 may be recessed portions, and the spaces between the plurality of motifs 83 may be convex portions. The plurality of motifs 83 and the spaces between the plurality of motifs 83 may be distinguished by the light and dark formed by the unevenness. Conversely, a plurality of motifs 83 may be convex portions, and the spaces between the plurality of motifs 83 may be recessed portions, and the plurality of motifs 83 and the spaces between the plurality of motifs 83 may be distinguished. Pattern 82 may be formed by a combination of the unevenness on the surface and color.

[0054] Returning to FIG. 4, pattern 82 may be provided on partition wall 64 that partitions accommodation space A1 and peripheral space PA1. By using the partition wall, a wide pattern can be provided, and map data for a wide range can be generated. That pattern 82 is provided on partition wall 64 includes both that the partition wall 64 itself is painted, processed, etc. to provide pattern 82, and that a panel or the like on which pattern 82 is provided is attached to partition wall 64.

[0055] For example, pattern 82 is provided on partition wall 64C or partition wall 64D adjacent to partition wall 64A in which opening 65 is formed. In FIG. 4, pattern 82 is provided on partition wall 64D, and camera 81 is provided on partition wall 64C so as to face pattern 82 through accommodation space A1, but it is not limited thereto. Pattern 82 may be provided on partition wall 64D, and camera 81 may be provided on partition wall 64C.

[0056] Wafer processing system 1 may further include image processing device 200. Image processing device 200 generates map data representing the distribution of the fluid flow in accommodation space A1 based on the change in the image of pattern 82 captured by camera 81. The distribution of the fluid flow is, for example, the relationship between the position in accommodation space A1 (the position in the image captured by camera 81) and the state of the fluid flow (for example, at least any one of the flow velocity, flow rate, and flow direction). The distribution of the fluid flow may be the relationship between the position in accommodation space A1 and the fluid density.

[0057] By digitizing the image blurring caused by the Schlieren effect according to the fluid flow, filtering processing, enhancement processing, etc. can be performed. Therefore, it is effective for more clearly visualizing the distribution of the fluid flow.

[0058] For example, the image processing apparatus 200 includes, as functional components (hereinafter referred to as "function blocks"), a map generation unit 211 and an image storage unit 212.

[0059] The map generation unit 211 generates map data representing the distribution of the fluid flow in the accommodation space A1 based on the change in the image of the pattern 82 captured by the camera 81. The map generation unit 211 may generate the map data based on the difference between the reference image of the accommodation space A1 captured by the camera 81, the timing at which the reference image was captured, and the evaluation image captured by the camera 81 at a timing when the distribution of the fluid flow is different. By basing on the difference between the reference image and the evaluation image, the change in the image of the pattern 82 is clarified. Thereby, map data that more clearly represents the distribution of the fluid flow in the accommodation space A1 is generated.

[0060] For example, the map generation unit 211 acquires a reference image from the camera 81 at a predetermined first timing and stores it in the image storage unit 212. Then, the map generation unit 211 acquires an evaluation image from the camera 81 at a predetermined second timing and calculates the difference between the reference image stored in the image storage unit 212 and the evaluation image. For example, the map generation unit 211 calculates the difference between the reference image and the evaluation image for each pixel of the camera 81. For example, the map generation unit 211 calculates, for each pixel, the difference between the pixel value in the reference image and the pixel value in the evaluation image. High-definition map data representing the flow distribution in pixel units can be generated. The pixel value is, for example, a numerical value representing brightness. For example, the map generation unit 211 generates matrix data indicating the difference between the pixel value in the reference image and the pixel value in the evaluation image for each pixel of the camera 81 as the map data.

[0061] The first timing is predetermined during a period when, for example, there is no flow in the fluid in the accommodation space A1 or the flow of the fluid in the accommodation space A1 is minute. The first timing may be predetermined during a period when there is no flow of the fluid in the accommodation space A1 toward the wafer W or the flow of the fluid in the accommodation space A1 toward the wafer W is minute. As an example, the first timing may be determined during a period when exhaust is performed from the exhaust port 67 and no exhaust is performed from the exhaust port 76.

[0062] The second timing is predetermined during a period when the flow of the fluid in the accommodation space A1 is large (for example, the flow velocity is high) as compared with the period when the first timing is determined. The second timing is predetermined during a period when the flow of the fluid in the accommodation space A1 toward the wafer W is large (for example, the flow velocity is high) as compared with the period when the first timing is determined. As an example, the second timing may be determined during a period when the processing liquid is supplied to the wafer W while exhaust is being performed from the exhaust port 76.

[0063] As described above, when the second timing (the timing for acquiring the evaluation image) is determined during the period when the processing liquid is supplied to the wafer W, the map generation unit 211 generates map data representing the distribution of the flow of the fluid (gas) with the processing liquid adhering to the wafer W. The map data generated with the processing liquid adhering to the wafer W is useful for analyzing the influence of the gas in the accommodation space A1 on the processing liquid.

[0064] In addition, since the vaporized matter from the processing liquid can change the refractive index of the gas, the difference in refractive index becomes large between the location where the vaporized matter is removed by the fluid and the location where the vaporized matter remains. As a result, since the change in refractive index due to the flow becomes larger due to the difference in the content of the vaporized matter, the shaking of the image due to the Schlieren effect can be further sharpened.

[0065] The camera 81 may repeatedly capture evaluation images. The map generation unit 211 may generate map data each time an evaluation image is captured by the camera 81. When repeatedly generating map data, the reference image will be repeatedly used. When the reference image is repeatedly used, due to a sudden displacement of the camera 81 or the like, there may be a difference in the conditions that should be the same between the time of capturing the reference image and the time of capturing the evaluation image. When such a condition difference occurs, it becomes impossible to distinguish whether the difference between the evaluation image and the reference image is due to the condition difference or due to the distribution of the flow, so it may become difficult to grasp the distribution of the flow based on the map data.

[0066] Therefore, the map generation unit 211 may update the reference image based on a plurality of evaluation images obtained by the camera 81 repeatedly capturing evaluation images, and generate map data based on the difference between the updated reference image and the evaluation image captured after the update of the reference image. Even when a sudden displacement of the camera 81 or the like occurs, the above-mentioned condition difference can be maintained at a low level by updating the reference image. For this reason, it is possible to continue generating map data that is easy to grasp the distribution of the flow.

[0067] For example, each time the map generation unit 211 generates map data based on the difference between the reference image and the evaluation image, it may update the reference image based on the used (used for generating map data) evaluation images. For example, the map generation unit 211 may generate a weighted average of the reference image and the evaluation image as a new reference image. The respective weights of the reference image and the evaluation image are determined in advance by preliminary experiments or the like.

[0068] The image processing apparatus 200 may further include a map display unit 213 as a functional block. The map display unit 213 displays, on a display device (for example, the display device of the user interface 296 described later), a map image representing the distribution of the fluid flow in the accommodation space A1 based on map data. For example, the map display unit 213 performs enhancement processing, filtering processing, etc. on the map data to generate display data, and displays a map image based on the display data. For example, the map display unit 213 displays a map image in which the state of the flow is represented by colors for each part in the image of the pattern 82.

[0069] FIG. 6 is an enlarged view of a part of the reference image and the evaluation image. (a) is the reference image, and (b) is the evaluation image. As shown in FIG. 6, the camera 81 has a plurality of pixels 87. The plurality of pixels 87 are arranged in a matrix at a pitch P2. The arrangement pitch (the above pitch P1) of the plurality of motifs 83 in the image of the pattern 82 may be larger than the arrangement pitch (pitch P2) of the plurality of pixels 87.

[0070] In the reference image 300 of FIG. 6, the line 84 between the motifs 83 is imaged on the pixels 87A, 87B, 87C, 87D, and is not imaged on the pixels 87E, 87F, 87G, 87H. In the evaluation image 400 of FIG. 6, due to the schlieren effect, the imaging position of the line 84 has changed from the reference image 300. For example, the part that was imaged on the pixel 87C in the reference image 300 is applied to both the pixels 87C and 87G in the evaluation image 400. Also, the part that was imaged on the pixel 87D in the reference image 300 has completely moved to the pixel 87H. In this example, at least in the pixels 87C, 87D and the pixels 87G, 87H, the difference between the pixel value in the reference image 300 and the pixel value in the evaluation image 400 becomes large. Therefore, it is shown that a fluid flow has occurred in the region through which the part imaged on at least the pixels 87C, 87D and the pixels 87G, 87H has passed.

[0071] Returning to FIG. 4, the substrate processing apparatus 50 may further include a temperature control unit 85. The temperature control unit 85 makes the temperature of the fluid in the accommodation space A1 different from the timing when the reference image was taken (e.g., the first timing above) at the timing when the evaluation image is taken (e.g., the second timing above). For example, the temperature control unit 85 heats or cools the fluid upstream of the fluid flow generated in the accommodation space A1. For example, when the exhaust port 76 opens into the cup 72 at the lower part of the cup 72, the upper part of the cup 72 can be the upstream of the fluid flow. In this case, the temperature control unit 85 may heat or cool the fluid above the cup 72.

[0072] When the fluid is heated or cooled upstream of the flow, the heated or cooled fluid flows into the part where the flow occurs, and the temperature difference becomes large between the part where the flow occurs and the part where no flow occurs. For this reason, the difference in refractive index between the part where the flow occurs and the part where no flow occurs is enlarged by the temperature difference. In this way, by making the change in refractive index due to the flow larger by the temperature difference, the blurring of the image due to the schlieren effect can be further sharpened.

[0073] The temperature control unit 85 may have a thermoelectric element provided in the fluid flow path and be configured to supply power to the thermoelectric element to change the temperature of the fluid. The thermoelectric element is an element that heats or cools the periphery by supplying power. Examples of the thermoelectric element include a Peltier element and the like. The temperature control unit 85 can be easily turned on and off.

[0074] The temperature control unit 85 only needs to be arranged so that it can heat or cool at least the fluid flowing within the generation range of the map data, and does not necessarily have to be arranged above the cup 72. The temperature control unit 85 may be arranged within the field of view of the camera 81.

[0075] The substrate processing apparatus 50 may further include an addition unit 86 instead of, or in addition to, the temperature control unit 85. The addition unit 86 supplies an additive that changes the refractive index to the fluid in the accommodation space A1 at the timing when the evaluation image is captured (for example, the above-described second timing). Examples of the additive include vaporized organic solvents (for example, vaporized acetone) and the like. For example, the addition unit 86 supplies the additive to the fluid upstream of the flow of the fluid generated in the accommodation space A1. For example, the addition unit 86 supplies the additive to the fluid above the cup 72.

[0076] When the additive is supplied to the fluid upstream of the flow, the fluid containing the additive flows into the portion where the flow occurs, and the difference in the content of the additive becomes large between the portion where the flow occurs and the portion where no flow occurs. For this reason, the difference in refractive index between the portion where the flow occurs and the portion where no flow occurs is enlarged due to the difference in the content of the additive. In this way, by increasing the change in refractive index due to the flow by the difference in the content of the additive, the blurring of the image due to the Schlieren effect can be further sharpened.

[0077] FIG. 7 is a plan view showing a modified example of the substrate processing apparatus. As shown in FIG. 7, the pattern 82 may be provided on a surface F1 inclined with respect to a surface VP1 perpendicular to the optical axis OAx of the camera 81. For example, the optical axis OAx of the camera 81 may be inclined with respect to the normal of the inner surface of the partition wall 64D on which the pattern 82 is provided.

[0078] Even when the plurality of motifs 83 are uniform and arranged at a constant pitch, the sizes can be made different between the plurality of motifs 83 in the image of the pattern 82. By making the sizes different between the plurality of motifs 83 in the image of the pattern 82, the blurring of the image due to the Schlieren effect can be further sharpened.

[0079] FIG. 8 is a cross-sectional view showing another modification of the substrate processing apparatus. As shown in FIG. 8, the substrate processing apparatus 50 may include a projection device 88 instead of the pattern 82. The projection device 88 projects the pattern 82 onto the projection surface F2. The surface F2 is provided so as to extend within the field of view of the camera 81 and is provided so as to be photographed by the camera 81 through the accommodation space A1. For example, when the camera 81 is provided on the partition wall 64C, the surface F2 is provided on the inner surface of the partition wall 64D. The projection device 88 may be configured to project the pattern 82 onto the surface F2 through the accommodation space A1. For example, the projection device 88 is provided on the partition wall 64C and projects the pattern 82 onto the surface F2 of the partition wall 64D through the accommodation space A1. Instead of including the pattern 82, including a projection device 88 that projects the pattern 82 onto the surface F2 prepared for projection is also included in including the pattern 82.

[0080] According to the projection device 88, the pattern 82 can be easily provided as compared with permanently installing the pattern 82. In addition, deterioration of the pattern 82 due to a processing liquid or the like can also be suppressed.

[0081] The projection device 88 may project the pattern 82 onto the surface F2 through the space A31 between the region of the surface F2 onto which the pattern 82 is projected and the camera 81. The light emitted from the projection device 88 is refracted twice, once when passing through the space A31 toward the surface F2 and once when passing through the space A31 toward the camera 81. As a result, the change in the pixel value due to refraction becomes larger compared to the case where the camera 81 photographs the pattern 82 fixed to the surface F2. Therefore, map data representing the distribution of the flow with higher sensitivity can be generated.

[0082] For example, the projection device 88 may project the pattern 82 onto the surface F2 through the space within the field of view of the camera 81. The projection device 88 may be arranged such that the light traveling from the projection device 88 towards the surface F2 and the light traveling from the surface F2 towards the camera 81 pass through a common space A31. The angle formed between the optical axis OAx1, which is the central axis of the light emitted from the projection device 88, and the optical axis OAx2, which is the central axis of the light incident on the camera 81, may be 30° or less, may be 20° or less, or may be 10° or less.

[0083] The camera 81 may be fixed relative to the projection device 88. The camera 81 being fixed relative to the projection device 88 means that the position of the camera 81 is fixed by the projection device 88 holding the camera 81. For example, in FIG. 8, the camera 81 is disposed on top of the projection device 88 fixed to the partition wall 64C, and the camera 81 is held by the projection device 88. By suppressing the relative vibration of the camera 81 with respect to the pattern 82, the blurring of the image due to the Schlieren effect can be further sharpened.

[0084] The surface F2 may have a color tone and texture that sharpen the pattern 82 projected by the projection device 88. The surface F2 may be formed by attaching a sheet to the partition wall 64D or the like, or may be formed by applying painting or processing to the partition wall 64D itself.

[0085] The arrangements of the camera 81 and the pattern 82 are not limited to the arrangements exemplified above, and can be changed in any way as long as the pattern 82 can be imaged by the camera 81 through the accommodation space A1. FIG. 9 shows a modification of the arrangements of the camera 81 and the pattern 82 in FIG. 3. The accommodation space A2 in FIG. 9 is the portion of the peripheral space PA1 that is connected to the accommodation space A1 through the opening 65. The accommodation space A2 houses the wafer W before being carried into the accommodation space A1 and after being carried out from the accommodation space A1.

[0086] In FIG. 9, the camera 81 and the pattern 82 are arranged near the opening 65 in the accommodation space A1 so as to sandwich the opening 65. For example, the camera 81 and the pattern 82 are arranged closer to the partition wall 64A where the opening 65 is formed between the partition wall 64A and the partition wall 64B. According to such an arrangement, the distribution of the fluid flowing from the accommodation space A2 (second accommodation space) to the accommodation space A1 through the opening 65 and the distribution of the fluid flowing from the accommodation space A1 to the accommodation space A2 (second accommodation space) through the opening 65 can be easily visualized.

[0087] In the above, the case where the camera 81 and the pattern 82 are provided in the patterning film forming apparatus 50A has been exemplified, but the processing apparatus in which the camera 81 and the pattern 82 are provided is not limited to the patterning film forming apparatus 50A. FIG. 10 is a plan view exemplifying the case where the camera 81 and the pattern 82 are provided in a heat treatment apparatus. The substrate processing apparatus 50 shown in FIG. 10 includes a heat treatment apparatus 50B.

[0088] The heat treatment apparatus 50B includes a chamber 60B and a hot plate 77. The chamber 60B has an accommodation space A11 for accommodating the wafer W. Similar to the chamber 60A, the chamber 60B has a top plate 61, a bottom plate 62, a peripheral wall 63, a shutter 66, and an exhaust port 67. An opening 65 is formed in the partition wall 64 of the peripheral wall 63. The substrate processing apparatus 50 includes an accommodation space A12 connected to the accommodation space A11 through the opening 65. The hot plate 77 supports the wafer W in the accommodation space A11 and heats it with a heater.

[0089] In FIG. 10, the camera 81 and the pattern 82 are arranged near the opening 65 in the accommodation space A12 so as to sandwich the opening 65. The map generation unit 211 may generate map data representing the distribution of the fluid flow around the opening 65 in a state where the temperature of the fluid in the accommodation space A12 is different from that of the fluid in the accommodation space A11 (the second accommodation space). For example, the map generation unit 211 acquires a reference image in a state where the shutter 66 closes the opening 65. Since the accommodation space A11 is heated by the hot plate 77 in a state where the opening 65 is closed by the shutter 66, the temperature of the fluid in the accommodation space A11 is different from that in the accommodation space A12. After the shutter 66 releases the opening 65 in this state, the map generation unit 211 acquires an evaluation image and generates map data based on the difference between the reference image and the evaluation image.

[0090] In the accommodation space A12, the fluid heated by the hot plate 77 flows into the portion where the flow from the opening 65 occurs, and the temperature difference becomes large between the portion where the flow occurs and the portion where no flow occurs. For this reason, the difference in refractive index between the portion where the flow occurs and the portion where no flow occurs is enlarged by the temperature difference. Therefore, the shaking of the image due to the Schlieren effect can be further sharpened, and the fluid flow between the accommodation space A11 and the accommodation space A12 can be clearly visualized. In this configuration, it can be said that the hot plate 77 functions as the temperature control unit 85 described above.

[0091] The substrate processing apparatus 50 may be included in another substrate processing system different from the wafer processing system 1. For example, the substrate processing apparatus 50 shown in FIG. 11 includes a gas processing apparatus 50C of another substrate processing system. The gas processing apparatus 50C is an apparatus that supplies a processing gas such as an etching gas to the wafer W.

[0092] The gas processing apparatus 50C includes a chamber 60C and a gas supply unit 78. The chamber 60C has an accommodation space A21 for accommodating the wafer W. The chamber 60C has a top plate 61, a bottom plate 62, and a peripheral wall 63, similar to the chamber 60A.

[0093] The gas supply unit 78 supplies a processing gas from above toward the wafer W held horizontally in the accommodation space A21. In FIG. 11, the camera 81 and the pattern 82 are provided on the partition walls 64C and 64D facing each other on the partition wall 64 of the peripheral wall 63, respectively. The map generation unit 211 generates map data representing the flow distribution of the processing gas as the flow distribution of the fluid. For example, the map generation unit 211 acquires a reference image in a state where the processing gas is not supplied from the gas supply unit 78. The map generation unit 211 acquires an evaluation image after the supply of the processing gas from the gas supply unit 78 is started, and generates map data based on the difference between the reference image and the evaluation image.

[0094] According to the substrate processing apparatus 50 of FIG. 11, map data useful for analyzing the supply state of the processing gas to the wafer W can be generated. In the accommodation space A21, the processing gas flows into the portion where the flow from the gas supply unit 78 occurs, and the amount of the processing gas increases between the portion where the flow occurs and the portion where the flow does not occur. For this reason, the difference in refractive index between the portion where the flow occurs and the portion where the flow does not occur is enlarged by the amount of the processing gas. Therefore, the shaking of the image due to the Schlieren effect can be further sharpened, and the flow of the processing gas can be clearly visualized. In this configuration, it can be said that the gas supply unit 78 functions as the addition unit 86 described above.

[0095] The image processing apparatus 200 may be configured to perform at least one of filter processing and enhancement processing of the map data using two-dimensional orthogonal polynomials. For example, as shown in FIG. 12, the image processing apparatus 200 may further include, as functional blocks, an expansion unit 221, a coefficient change unit 222, and a reconstruction unit 223. The expansion unit 221 expands the map data into a series of a plurality of components each represented by a two-dimensional orthogonal polynomial. For example, each of the plurality of components is matrix data having the same number of rows and columns as the map data. The series means data obtained by adding a plurality of components with weights. The weight (coefficient) of each of the plurality of components is determined so that the result of the addition matches the map data.

[0096] The coefficient change unit 222 changes the coefficients of one or more components to be changed among a plurality of components in the series. For example, when the purpose is filter processing, one or more components to be reduced by the filter processing among the plurality of components are the one or more components to be changed, and the coefficient change unit reduces the coefficients of the one or more components to be changed. When the purpose is enhancement processing, one or more components to be increased by the enhancement processing among the plurality of components are the one or more components to be changed, and the coefficient change unit increases the coefficients of the one or more components to be changed.

[0097] The reconstruction unit 223 reconstructs the map data based on the series in which the coefficients of one or more components to be changed are changed. For example, the reconstruction unit 223 reconstructs the map data by adding a plurality of components with weights.

[0098] The two-dimensional orthogonal polynomial is a two-dimensional Legendre polynomial. FIG. 13 is a schematic diagram illustrating a plurality of components each of which is a two-dimensional Legendre polynomial. The plurality of components include a component LP0 that does not form a pattern, a plurality of components LP1 that form a vertical stripe pattern, a plurality of components LP2 that form a horizontal stripe pattern, and a plurality of components LP3 that are a combination of a vertical stripe pattern and a horizontal stripe pattern.

[0099] For example, when the flow of the fluid is likely to occur along the vertical direction, the coefficient change unit 222 may use at least any one of the plurality of components LP1 as one or more components to be changed and increase the coefficients of the one or more components to be changed. Thereby, the distribution of the fluid flow is likely to be emphasized. Further, the coefficient change unit 222 may use at least any one of the plurality of components LP2 as one or more components to be changed and reduce the coefficients of the one or more components to be changed. Thereby, since the horizontal stripe pattern that has little relation to the fluid flow is reduced, it is possible to more easily grasp the distribution of the fluid flow.

[0100] The two-dimensional orthogonal polynomial is not necessarily limited to the two-dimensional Legendre polynomial. The two-dimensional orthogonal polynomial may be, for example, a two-dimensional Chebyshev polynomial.

[0101] FIG. 14 is a block diagram illustrating the hardware configuration of the image processing apparatus 200. As shown in FIG. 14, the image processing apparatus 200 has a circuit 290. The circuit 290 includes a processor 291, a memory 292, a storage 293, an image processing circuit 294, a power-on / off circuit 295, and a user interface 296.

[0102] The storage 293 includes, for example, one or more non-volatile storage media. Examples of the non-volatile storage media include a hard disk drive, a solid state drive, a flash memory, etc. The non-volatile storage media may include a portable storage media such as an optical disk. The storage 293 stores a program for causing the image processing apparatus 200 to generate map data representing the distribution of the fluid flow based on the change in the image of the pattern 82 captured by the camera 81. For example, the storage 293 stores a program for configuring the above-described respective functional blocks in the image processing apparatus 200.

[0103] The memory 292 includes one or more volatile storage media. Examples of the volatile storage media include a random access memory. The memory 292 temporarily stores the program loaded from the storage 293. The processor 291 includes one or more arithmetic devices. Examples of the arithmetic devices include a CPU (Central Processing Unit), or a GPU (Graphics Processing Unit), etc. The processor 291 configures the above-described respective functional blocks in the image processing apparatus 200 by executing the program loaded into the memory 292. The processor 291 may temporarily store the arithmetic result in the memory 292.

[0104] The image processing circuit 294 causes the camera 81 to execute shooting in response to a request from the processor 291, and acquires the captured image from the camera 81. The on-off circuit 295 starts or stops the projection of the pattern 82 by the projection device 88 in response to a request from the processor 291. The user interface 296 includes one or more input devices and one or more display devices. Examples of the input device include a keyboard or a mouse. Examples of the display device include a liquid crystal monitor. The input device may be incorporated in the display device to form a touch panel. The user interface 296 outputs an input to one or more input devices and displays text, images, etc. on one or more display devices in response to a request from the processor 291.

[0105] The image processing apparatus 200 may be incorporated in the control apparatus 100, or may be incorporated in hardware separate from the control apparatus 100. A network line such as a wide area network or a local area network may be interposed between the image processing apparatus 200 and the substrate processing apparatus 50.

[0106] 〔Visualization procedure〕 As an example of the visualization method, a visualization procedure executed by the image processing apparatus 200 is illustrated. This procedure includes the camera 81 directed at A1 acquiring an image obtained by shooting the pattern 82 provided so as to spread within the field of view of the camera 81 through A1, and generating map data representing the distribution of the fluid flow at A1 based on the change in the acquired image.

[0107] FIG. 15 is a flowchart exemplifying a visualization procedure. As shown in FIG. 15, the image processing apparatus 200 first executes steps S01, S02, S03, and S04. In step S01, the map generation unit 211 waits for the first timing. In step S02, the map generation unit 211 causes the camera 81 to start video shooting for generating a reference image. In step S03, the map generation unit 211 waits for the elapse of a predetermined time. In step S04, the map generation unit 211 generates a reference image based on a plurality of still images constituting the video captured by the camera 81. For example, the map generation unit 211 generates a reference image by performing an averaging process or the like on the plurality of still images and stores it in the image storage unit 212. Thereby, the reference image is acquired.

[0108] Next, the image processing apparatus 200 executes steps S05, S06, S07, and S08. In step S05, the map generation unit 211 waits for the second timing. In step S06, the map generation unit 211 causes the camera 81 to start video shooting for generating an evaluation image. In step S07, the map generation unit 211 waits for the result of a predetermined time. In step S08, the map generation unit 211 generates an evaluation image based on a plurality of still images constituting the video captured by the camera 81. For example, the map generation unit 211 generates an evaluation image by performing an averaging process or the like on the plurality of still images and stores it in the image storage unit 212.

[0109] Next, the image processing apparatus 200 executes steps S11, S12, S13, and S14. In step S11, the map generation unit 211 generates map data based on the difference between the reference image and the evaluation image. In step S12, the map generation unit 211 performs an enhancement process on the map data. The enhancement process is, for example, a process of enlarging the difference in pixel values between pixels. In step S13, the map generation unit 211 performs a filtering process on the map data. The filtering process is a process of removing values caused by noise from the pixel values. The execution order of the enhancement process and the filtering process is not limited to this, and the enhancement process may be executed after the filtering process.

[0110] In step S14, the map display unit 213 displays the map image based on the map data after the enhancement process and the filtering process. Thus, the visualization procedure is completed.

[0111] When the image processing apparatus 200 includes a developing unit 221, a coefficient changing unit 222, and a reconstructing unit 223, steps S12 and S13 may be executed by the developing unit 221, the coefficient changing unit 222, and the reconstructing unit 223 as described above.

[0112] FIG. 16 is a flowchart showing a modification example of the visualization procedure, which is different from the flowchart of FIG. 15 in that generation of an evaluation image and generation of map data are repeated. In the flowchart of FIG. 16, steps S01 to S14 are common to steps S01 to S14 in the flowchart of FIG. 15.

[0113] In the flowchart of FIG. 16, after the image processing apparatus 200 displays the map image in step S14, it executes step S15. In step S15, the map generation unit 211 updates the reference image. For example, the map generation unit generates a weighted average of the evaluation image generated in step S08 and the reference image as a new reference image, and stores it in the image storage unit 212.

[0114] Next, the image processing apparatus 200 executes step S16. In step S16, the map generation unit 211 waits for a predetermined period to elapse since the start point of step S06. Thereafter, the image processing apparatus 200 returns the process to step S06. Thereby, generation of the evaluation image, generation of the map data, display of the map image, and update of the reference image are repeatedly executed at the above-mentioned predetermined period.

[0115] 〔Summary〕 The embodiments illustrated above include the following configurations. (1) A substrate processing system 1 includes a substrate processing apparatus 50 having an accommodation space A1 for accommodating a substrate W, a camera 81 directed toward the accommodation space A1, a pattern 82 provided so as to spread within the field of view of the camera 81 and imaged by the camera 81 through the accommodation space A1, and a map generation unit 211 that generates map data representing the distribution of the fluid flow in the accommodation space A1 based on changes in the image of the pattern 82 captured by the camera 81. Due to the Schlieren effect, the fluctuation of the image generated according to the fluid flow is sharpened by the pattern 82, so that map data clearly representing the distribution of the fluid flow in the accommodation space A1 is generated. Therefore, the distribution of the fluid flow in the substrate processing apparatus 50 can be easily visualized.

[0116] (2) The map generation unit 211 of the substrate processing system 1 according to (1) generates map data based on the difference between a reference image 300 of the accommodation space A1 captured by the camera 81 and an evaluation image 400 captured by the camera 81 at a timing when the distribution of the fluid flow is different from the timing when the reference image 300 was captured. Based on the difference between the reference image 300 and the evaluation image 400, the change in the image of the pattern 82 is clarified. Thereby, map data that more clearly represents the distribution of the fluid flow in the accommodation space A1 is generated. Therefore, the distribution of the fluid flow in the substrate processing apparatus 50 can be more clearly visualized.

[0117] (3) The camera 81 has a plurality of pixels 87, and the map generation unit 211 of the substrate processing system 1 according to (2) generates map data based on the difference between the pixel 87 value in the evaluation image 400 and the pixel 87 value in the reference image 300 for each of the plurality of pixels 87. High-definition map data can be generated.

[0118] (4) The substrate processing system 1 according to any one of (1) to (3) includes a plurality of motifs 83 arranged so as to be dispersed within the field of view of the camera 81. The shaking of the image due to the Schlieren effect is further sharpened by a plurality of motifs 83. Therefore, the distribution of the fluid flow in the substrate processing apparatus 50 can be visualized more clearly.

[0119] (5) The camera 81 has a plurality of pixels 87, and the array pitch of the plurality of motifs 83 in the image of the pattern 82 is larger than the array pitch of the plurality of pixels 87, in the substrate processing system 1 described in (4). The occurrence of moiré can be suppressed.

[0120] (6) The pattern 82 includes a plurality of motifs 83 arranged at a constant pitch and being uniform, and is provided on a surface inclined with respect to the surface perpendicular to the optical axis of the camera 81, in the substrate processing system 1 described in (4) or (5). In the image of the pattern 82, by making the sizes different between the plurality of motifs 83, the shaking of the image due to the Schlieren effect can be further sharpened.

[0121] (7) The pattern 82 is provided on a partition wall that partitions the accommodation space A1 and the peripheral space PA1, in the substrate processing system 1 according to any one of (1) to (6). By using the partition wall, a wide pattern 82 can be provided, and map data for a wide range can be generated.

[0122] (8) The substrate processing system 1 according to any one of (1) to (7) further includes a projection device 88 that is provided so as to extend within the field of view of the camera 81 and projects the pattern 82 onto a surface that is photographed by the camera 81 through the accommodation space A1. The pattern 82 can be easily provided. Deterioration of the pattern 82 due to a processing liquid or the like can also be suppressed.

[0123] (9) The projection device 88 projects the pattern 82 onto the surface through the space A31 between the region of the surface onto which the pattern 82 is projected and the camera 81, in the substrate processing system 1 described in (8). The light emitted from the projection device 88 will be refracted twice, once when passing through the space A31 towards the surface and once when passing through the space A31 towards the camera 81. As a result, the change in pixel values due to refraction becomes larger compared to the case where the camera 81 captures the pattern 82 fixed on the surface. Therefore, map data representing the flow distribution with higher sensitivity can be generated.

[0124] (10) The substrate processing system 1 according to (8), wherein the camera 81 is fixed with respect to the projection device 88. By suppressing the relative vibration of the camera 81 with respect to the pattern 82, the shaking of the image due to the Schlieren effect can be further sharpened.

[0125] (11) The substrate processing system 1 according to (2) or (3), further comprising a temperature control unit 85 that makes a difference in the temperature of the fluid in the accommodation space A1 at the timing when the evaluation image 400 is captured compared to the timing when the reference image 300 was captured. By increasing the change in refractive index due to the flow, the shaking of the image due to the Schlieren effect can be further sharpened.

[0126] (12) The substrate processing system 1 according to (11), wherein the temperature control unit 85 has a thermoelectric element provided in the fluid flow path, and supplies power to the thermoelectric element to change the temperature of the fluid. The temperature control unit 85 can be easily turned on and off.

[0127] (13) The substrate processing system 1 according to (2) or (3), further comprising an addition unit 86 that supplies an additive that changes the refractive index to the fluid in the accommodation space A1 at the timing when the evaluation image 400 is captured. By increasing the change in refractive index due to the flow, the shaking of the image due to the Schlieren effect can be further sharpened.

[0128] (14) The camera 81 repeatedly captures evaluation images, and the map generation unit 211 generates map data each time an evaluation image is captured by the camera 81, for the substrate processing system 1 described in (2) or (3). (2) The distribution of the fluid can be continuously monitored.

[0129] (15) The map generation unit 211 updates the reference image based on a plurality of evaluation images obtained by the camera 81 repeatedly capturing evaluation images, and generates map data based on the difference between the updated reference image and the evaluation image captured after the update of the reference image, for the substrate processing system 1 described in (14). When the reference image is repeatedly used, due to a sudden misalignment of the camera 81 or the like, there may be a difference in the conditions that should be the same between the time of capturing the reference image and the time of capturing the evaluation image. When such a condition difference occurs, it becomes impossible to distinguish whether the difference between the evaluation image and the reference image is due to the condition difference or due to the distribution of the flow, so it may become difficult to grasp the distribution of the flow based on the map data. On the other hand, by updating the reference image, even when a sudden misalignment of the camera 81 or the like occurs, the above-described condition difference can be maintained at a low level. Therefore, it is possible to continue generating map data that makes it easy to grasp the distribution of the flow.

[0130] (16) The substrate processing system 1 according to any one of (1) to (15) further includes a development unit 221 that develops the map data into a series of a plurality of components each represented by a two-dimensional orthogonal polynomial, a coefficient change unit 222 that changes the coefficients of one or more target components to be changed among the plurality of components in the series, and a reconstruction unit that reconstructs the map data based on the series in which the coefficients of one or more target components to be changed are changed. (14) Filter processing for removing components that make it difficult to grasp the distribution of the fluid flow, and enhancement processing for enhancing the distribution of the fluid flow can be easily performed.

[0131] (17) The two-dimensional orthogonal polynomial is a two-dimensional Legendre polynomial, for the substrate processing system 1 described in (16). Filter processing and enhancement processing can be performed more easily.

[0132] (18) The map generation unit 211 generates map data representing the distribution of the gas flow as the distribution of the fluid flow, for the substrate processing system 1 according to any one of (1) to (17). The distribution of the gas flow can be easily visualized.

[0133] (19) The substrate processing apparatus 50 further has a liquid supply unit 73 that supplies a processing liquid to the substrate W accommodated in the accommodation space A1, and the map generation unit 211 generates map data representing the distribution of the gas flow in a state where the processing liquid adheres to the substrate W, for the substrate processing system 1 according to (18). Map data useful for analyzing the influence of the gas in the accommodation space A1 on the processing liquid can be generated.

[0134] (20) The substrate processing apparatus 50 further has a second accommodation space A11 connected to the accommodation space A12 through the opening 65, and the map generation unit 211 generates map data representing the distribution of the fluid flow around the opening 65 in a state where the temperature of the fluid in the accommodation space A12 is different from that of the fluid in the second accommodation space A11, for the substrate processing system 1 according to any one of (1) to (19). The fluid flow between the accommodation space A12 and the second accommodation space A11 can be easily visualized.

[0135] (21) The substrate processing apparatus 50 further has a gas supply unit 78 that supplies a processing gas to the substrate W accommodated in the accommodation space A1, and the map generation unit 211 generates map data representing the distribution of the processing gas flow as the distribution of the fluid flow, for the substrate processing system 1 according to any one of (1) to (20). Map data useful for analyzing the supply state of the processing gas to the substrate W can be generated.

[0136] (22) A substrate processing apparatus 50 comprising: a housing space A1 for housing a substrate W; a camera 81 directed toward the housing space A1; and a pattern 82 provided so as to extend within the field of view of the camera 81, the pattern 82 being imaged by the camera 81 through the housing space A1 and changing an image captured by the camera 81 in accordance with a change in the refractive index of a fluid in the housing space A1.

[0137] (23) A method for visualizing the distribution of fluid flow in a housing space A1 in which a substrate W is housed in a substrate processing apparatus 50, the method comprising: obtaining, by a camera 81 directed toward the housing space A1, an image captured through the housing space A1 of a pattern 82 provided so as to extend within the field of view of the camera 81; and generating map data representing the distribution of fluid flow in the housing space A1 based on a change in the obtained image.

[0138] Although the embodiments have been described above, the present disclosure is not necessarily limited to the above-described embodiments, and various modifications are possible without departing from the gist thereof. A semiconductor wafer has been exemplified as an example of the substrate, but it is not limited thereto. For example, the substrate may be a glass substrate. Also, although the case where the fluid is a gas has been mainly exemplified, the fluid may be a liquid. Even when the fluid is a liquid, the Schlieren effect can be obtained, and thus it is possible to visualize the distribution of fluid flow by the above-described configuration.

Explanation of Reference Numerals

[0139] 1... substrate processing system, W... substrate, 50... substrate processing apparatus, A1... housing space, PA1... peripheral space, 65... opening, 73... liquid supply unit, 81... camera, 82... pattern, 83... motif, 211... map generation unit, 87... pixel, 300... reference image, 400... evaluation image, 85... temperature control unit, 86... addition unit, 88... projection device, 78... gas supply unit.

Claims

1. a substrate processing apparatus having an accommodation space for accommodating a substrate; A camera directed toward the storage space; a pattern that is provided so as to extend within the field of view of the camera and is photographed by the camera through the accommodation space; a map generating unit that generates map data representing a distribution of a fluid flow in the accommodation space based on a change in the image of the pattern captured by the camera; A substrate processing system comprising:

2. the map generation unit generates the map data based on a difference between a reference image of the accommodation space taken by the camera and an evaluation image taken by the camera at a timing when the distribution of the flow of the fluid is different from the timing when the reference image was taken. The substrate processing system of claim 1 .

3. the camera has a plurality of pixels; the map generation unit generates the map data based on a difference between a pixel value in the evaluation image and a pixel value in the reference image for each of the plurality of pixels. The substrate processing system according to claim 2 .

4. The pattern is A plurality of motifs arranged to be distributed within the field of view of the camera; The substrate processing system according to any one of claims 1 to 3.

5. the camera has a plurality of pixels; an arrangement pitch of the plurality of motifs in the image of the pattern is greater than an arrangement pitch of the plurality of pixels; The substrate processing system according to claim 4 .

6. The pattern includes the plurality of motifs arranged at a constant pitch and being uniform, and is provided on a plane inclined with respect to a plane perpendicular to the optical axis of the camera. The substrate processing system according to claim 4 .

7. The pattern is provided on a partition wall that separates the storage space from a peripheral space. The substrate processing system according to any one of claims 1 to 3.

8. The camera further includes a projection device that is disposed so as to extend within a field of view of the camera and projects the pattern onto a surface that is photographed by the camera through the storage space. The substrate processing system according to any one of claims 1 to 3.

9. the projection device projects the pattern onto the surface through a space between a region of the surface onto which the pattern is projected and the camera; The substrate processing system of claim 8 .

10. The camera is fixed relative to the projection device. The substrate processing system of claim 8 .

11. a temperature adjusting unit that changes a temperature of the fluid in the accommodation space at a timing when the evaluation image is captured compared to a timing when the reference image is captured, 4. The substrate processing system according to claim 2 or 3.

12. The temperature adjustment unit has a thermoelectric element provided in a flow path of the fluid, and changes the temperature of the fluid by supplying power to the thermoelectric element. The substrate processing system of claim 11.

13. an additive unit that supplies an additive that changes a refractive index to the fluid in the accommodation space at a timing when the evaluation image is captured; 4. The substrate processing system according to claim 2 or 3.

14. The camera repeatedly captures the evaluation images, the map generation unit generates the map data every time the evaluation image is captured by the camera.

4. The substrate processing system according to claim 2 or 3.

15. the map generation unit updates the reference image based on a plurality of evaluation images obtained by repeatedly photographing the evaluation image with the camera, and generates the map data based on a difference between the updated reference image and the evaluation image photographed after the reference image is updated. The substrate processing system of claim 14.

16. an expansion unit that expands the map data into a series of a plurality of components, each of which is represented by a two-dimensional orthogonal polynomial; a coefficient modification unit that modifies a coefficient of one or more modification target components among the plurality of components in the series; and a reconstruction unit that reconstructs the map data based on the series in which the coefficients of the one or more change target components are changed. The substrate processing system according to any one of claims 1 to 3.

17. The two-dimensional orthogonal polynomial is a two-dimensional Legendre polynomial. The substrate processing system of claim 16.

18. the map generating unit generates the map data representing a distribution of a gas flow as a distribution of the fluid flow. The substrate processing system according to any one of claims 1 to 3.

19. the substrate processing apparatus further includes a liquid supply unit that supplies a processing liquid to the substrate accommodated in the accommodation space, the map generating unit generates the map data representing a distribution of the gas flow in a state in which the processing liquid is attached to the substrate. The substrate processing system of claim 18.

20. the substrate processing apparatus further includes a second accommodation space connected to the accommodation space via an opening, the map generation unit generates the map data representing a distribution of a flow of the fluid around the opening in a state in which the fluid in the accommodation space and the fluid in the second accommodation space have different temperatures. The substrate processing system according to any one of claims 1 to 3.

21. the substrate processing apparatus further includes a gas supply unit that supplies a processing gas to the substrate accommodated in the accommodation space, the map generator generates the map data representing a flow distribution of the process gas as a flow distribution of the fluid. The substrate processing system according to any one of claims 1 to 3.

22. a housing space for housing the substrate; A camera directed toward the storage space; The camera is provided so as to extend within the field of view of the camera, and the camera captures the image through the storage space, and the image is captured according to a change in the refractive index of the fluid in the storage space. A pattern for changing an image captured by the camera; A substrate processing apparatus comprising:

23. 1. A method for visualizing a distribution of a fluid flow in a storage space in a substrate processing apparatus, the method comprising: A camera facing the storage space captures an image of a pattern provided so as to extend within a field of view of the camera through the storage space, and the image is acquired; generating map data representing a distribution of the flow of the fluid in the accommodation space based on the change in the acquired image; Visualization methods including:

Images