Monitoring device, monitoring method, and monitoring program

Abstract

A monitoring device according to one aspect of the present disclosure comprises: an image acquisition unit for acquiring an image obtained by imaging by a camera directed to a processing space to which a fluid for substrate processing is supplied in a state in which a substrate is accommodated; and a state information generation unit for generating information indicating the state of the flow of the fluid in an imaging region by the camera in the processing space on the basis of a change in the image.

Description

Monitoring device, monitoring method, and monitoring program

[0001] The present disclosure relates to a monitoring device, a monitoring method, and a monitoring program.

[0002] In Patent Document 1, a tracer that moves by this airflow is mixed into the airflow to be visualized, and a beam-shaped laser beam including wavelengths in a specific visible light range is repeatedly scanned and irradiated onto the airflow, and the 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. A method for visualizing an airflow is disclosed.

[0003] Japanese Patent Application Laid-Open No. 7-35764

[0004] The present disclosure provides a technique capable of easily grasping the state of a processing fluid in a processing space.

[0005] A monitoring device according to one aspect of the present disclosure includes an image acquisition unit that acquires an image obtained by photographing with a camera directed at a processing space in which a fluid for substrate processing is supplied in a state where a substrate is accommodated, and a state information generation unit that generates information indicating the state of the flow of the fluid in the imaging region by the camera in the processing space based on the change in the image.

[0006] According to the present disclosure, a technique capable of easily grasping the state of a processing fluid in a processing space is provided.

[0007] Figure 1 is a plan view illustrating the configuration of a wafer processing system. Figure 2 is a front view illustrating the configuration of a wafer processing system. Figure 3 is a schematic diagram illustrating the functional configuration of a substrate processing device and a monitoring device. Figure 4 is a schematic diagram illustrating a substrate processing device. Figure 5 is a diagram illustrating a pattern. Figure 6 is a diagram illustrating a reference image and an evaluation image. Figure 7 is a schematic diagram illustrating a substrate processing device. Figure 8 is a schematic diagram illustrating a substrate processing device. Figure 9 is a schematic diagram illustrating a substrate processing device. Figure 10 is a block diagram illustrating the functional configuration of a monitoring device. Figure 11 is a diagram illustrating multiple components of map data. Figure 12 is a block diagram illustrating the hardware configuration of a monitoring device. Figure 13 is a flowchart illustrating the visualization procedure. Figure 14 is a flowchart illustrating the visualization procedure.

[0008] The wafer processing system as a substrate processing system according to this embodiment will be described below with reference to the drawings. In this specification, elements having substantially the same functional configuration are denoted by the same reference numerals to avoid redundant explanations. The dimensional ratios of each element are not limited to those shown. Some drawings show a Cartesian coordinate system defined by the X, Y, and Z axes, where the Z axis corresponds to the vertical direction.

[0009] [Wafer Processing System] First, the configuration of the wafer processing system according to this embodiment will be described. Figures 1 and 2 are a schematic plan view and a front view, respectively, showing the general configuration of the wafer processing system 1. In this embodiment, the case in which the wafer processing system 1 is a photolithography processing system that performs resist film formation processing and development processing on a wafer W (substrate) will be described as an example.

[0010] As shown in Figure 1, the wafer processing system 1 includes a cassette station 2 for loading and unloading cassettes C containing multiple wafers W, and a processing station 3 equipped with multiple processing devices for performing 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 for transferring wafers W between the processing station 3 and an adjacent exposure apparatus (not shown) on the opposite side are integrally connected. Although two processing stations 3 are installed between the cassette station 2 and the interface station 4 as shown in Figure 1, there may be one or three or more processing stations.

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

[0012] The cassette station 2 may also be equipped with an inspection device (not shown) for inspecting the wafer W, located at a position accessible by either the wafer transport device 22 or 23.

[0013] The processing station 3 is provided with multiple blocks, for example, three blocks G1, G2, and G4, which are the first, second, and fourth blocks. As shown in Figure 2, multiple layers 31, each containing the first and second blocks G1 and G2, are stacked vertically. For example, the first block G1 is provided on the front side of the processing station 3 (the negative X-direction side in Figure 1), and the second block G2 is provided on the rear side of the processing station 3 (the positive X-direction side in Figure 1). A fourth block G4 is provided on the interface station 4 side of the processing station 3 (the positive Y-direction side in Figure 1) or at the connection point with another adjacent processing station 3. The fourth block G4 may be equipped with multiple transfer devices arranged vertically. The aforementioned third block G3 may also be provided inside the processing station 3.

[0014] The first block G1 contains multiple processing devices, such as patterning film forming devices and developing devices (both not shown). The patterning film forming devices may include, for example, a resist film forming device as well as an anti-reflective film forming device. For example, multiple processing devices are arranged horizontally. The number, arrangement, and types of these processing devices can be arbitrarily selected.

[0015] These patterning film forming apparatuses and developing apparatuses perform, for example, supplying a predetermined processing solution or a predetermined gas onto the wafer W. In this way, the patterning film forming apparatuses form resist films used as masks when forming patterns on the lower layer films, or anti-reflective films for efficient light irradiation processes, such as exposure processing. Meanwhile, the developing apparatuses remove a portion of the exposed resist film to form the uneven shape that serves as the mask.

[0016] For example, in the second block G2, heat treatment devices (not shown) for performing heat treatment such as heating and cooling of the wafer W are arranged in the vertical and horizontal directions. Also in the second block G2, although not shown, a hydrophobic treatment device for performing hydrophobic treatment to improve the adhesion between the resist solution and the wafer W, and a peripheral exposure device for exposing the outer periphery of the wafer W are arranged in the vertical (Z direction in Figure 2) and horizontal directions. The number and arrangement of these heat treatment devices, hydrophobic treatment devices, and peripheral exposure devices can also be arbitrarily selected.

[0017] As shown in Figure 1, a wafer transport region 32 is formed in the area sandwiched between the first block G1 and the second block G2 in a plan view. A wafer transport device 33, for example, is arranged in the wafer transport region 32.

[0018] The wafer transfer device 33 has a transfer arm that can move, for example, in the X, Y, θ, and vertical directions. The wafer transfer device 33 moves within the wafer transfer area 32 and can transfer wafers W to predetermined devices in the surrounding first block G1, second block G2, third block G3, and fourth block G4. If there are multiple processing stations 3 as shown in Figure 1, the wafer transfer device 33 provided at the processing station 3 located on the interface station 4 side can transfer wafers W to predetermined devices in the fifth block G5, which will be described later, in addition to the first, second, and fourth blocks G1, G2, and G4.

[0019] Multiple wafer transfer devices 33 are arranged, for example, vertically. One wafer transfer device 33 can transfer a wafer W to a predetermined device located at the height of multiple upper layers 31 (see Figure 2) among multiple layers stacked vertically. Another wafer transfer device 33 can transfer the wafer W to a predetermined device located at the height of multiple layers 31 located below those layers 31. Multiple wafer transfer areas 32 are provided to enable this type of wafer transfer of W. The number of wafer transfer devices 33 and the number of layers 31 corresponding to one wafer transfer device 33 can be arbitrarily selected, such as providing one wafer transfer device 33 for each layer 31.

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

[0021] Interface station 4 includes a fifth block G5 equipped with multiple transfer devices, and wafer transport devices 41 and 42. Interface station 4 transports wafers W between the fifth block G5, where wafers W are transferred by wafer transport device 33, and the exposure apparatus using wafer transport device 41 or 42. For this purpose, wafer transport devices 41 and 42 are each equipped with drive mechanisms in directions such as the X direction, Y direction, up and down direction, and around the vertical axis (θ direction) as needed, and may also be equipped with drive mechanisms in all directions. At least one of wafer transport devices 41 and 42 can support the wafer W and transport the wafer W between the transfer devices in the fifth block G5 and the exposure apparatus.

[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 in a position accessible by either the wafer transport device 41 or 42.

[0023] The inspection device may be provided in the cassette station 2 as described above, but it may also be provided in the processing station 3 and the interface station 4 in a position accessible by any of the transport arms (33, 41, 42 in Figure 1 or Figure 2) located inside each of them.

[0024] The wafer processing system 1 described above 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 that controls the processing of wafers W in the wafer processing system 1. The program storage unit also stores a program that controls the operation of the various processing devices and transport devices and other drive systems to realize wafer processing in the wafer processing system 1. Note that the above program may have been recorded on a storage medium H that is readable by the computer and installed from the storage medium H to the control device 100.

[0025] [Operation of the 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 explained.

[0026] First, a cassette C containing multiple wafers W is brought into the cassette station 2 of the wafer processing system 1 and placed on the cassette tray 21. Next, each wafer W in the cassette C is sequentially removed by the wafer transport device 22 or 23 and transported to the transfer device of the third block G3.

[0027] The wafer W, transported to the transfer device of the third block G3, is supported by the wafer transfer device 33 and transported to a hydrophobic treatment device located in the second block G2, where a hydrophobic treatment is performed. Next, the wafer transfer device 33 transports the wafer W to a resist film forming device where a resist film is formed on the wafer W. After that, the wafer W is transported to a heat treatment device for pre-baking before being transported to the transfer device of the fifth block G5. Note that if there are multiple processing stations 3 as shown in Figures 1 and 2, the wafer W is first placed in the transfer device of the fourth block G4 before being transported to the transfer device of the fifth block G5, and then transferred between the multiple wafer transfer devices 33. In addition, if necessary, the wafer W may be transported by the wafer transfer device 33 to a peripheral exposure device where the peripheral portion of the wafer W is exposed.

[0028] The wafer W, which has been transported to the transfer device of the fifth block G5, is then transported to the exposure device by wafer transport devices 41 and 42 and exposed in a predetermined pattern. Note that the wafer W may be cleaned by a cleaning device before the exposure process.

[0029] The exposed wafer W is transported to the transfer device for the fifth block G5 by wafer transport devices 41 and 42. The wafer W is then transported to the heat treatment device 33 for post-exposure baking.

[0030] The wafer W, which has been baked after exposure, is transported to a developing apparatus by a wafer transport device 33 and developed. After development is complete, the wafer W is transported to a heat treatment apparatus by the wafer transport device 33 and subjected to post-bake treatment.

[0031] Subsequently, the wafer W is transported by the wafer transport device 33 to the transfer device of the third block G3, and then transported by the wafer transport device 22 or 23 of the cassette station 2 to the cassette C on the predetermined cassette mounting table 21. In this way, the series of photolithography processes is completed.

[0032] It should be noted that the wafer processing system in this disclosure is not limited to the configuration and operation described above. For example, in the embodiment described above, the wafer W is transferred between the interface station 4 and the exposure apparatus, but it is not necessary for the interface station 4 to be directly connected to the exposure apparatus. In that case, for example, the wafer W is transported from the cassette station 2 to the processing station 3, the necessary processing is performed, and then it is transported back to the cassette station 2 for external transport. Also, any processing devices listed that are not necessary may not be provided, or processing may not be performed in those devices.

[0033] [Substrate Processing Apparatus] A schematic example of a cross-section of the substrate processing apparatus in a side view is shown in part of Figure 3. A schematic plan view of the substrate processing apparatus is shown in Figures 3 and 4. The substrate processing apparatus 50 shown in Figures 3 and 4 is included in the wafer processing system 1. The substrate processing apparatus 50 is a device that processes a wafer W to be processed using a substrate processing fluid while the wafer W is contained within the apparatus. The substrate processing fluid used by the substrate processing apparatus 50 includes a substrate processing gas.

[0034] The substrate processing apparatus 50 includes, for example, an apparatus that supplies a developing gas such as acetic acid gas to the wafer W to perform development, and HMDS (hexamethyldisilazane: (CH ３ ) ３ SiNHSi(CH ３ ) ３ An example is an apparatus that supplies a gas containing ) to a wafer W to perform hydrophobic treatment. Hereinafter, the fluid used by the substrate processing apparatus 50 for substrate processing will be referred to as the "processing fluid". The substrate processing apparatus 50 has, for example, a chamber 60, a substrate support section 64, and a fluid supply section 70.

[0035] Chamber 60 forms a processing space for performing substrate processing on a wafer W using a processing fluid. The wafer W to be processed is housed in the processing space within chamber 60. In Figure 3, the processing space is indicated by "A1". Processing space A1 is a space separated from the external space (for example, the space in which the wafer W is transported).

[0036] The chamber 60 may include an upper chamber 61 and a lower chamber 62. The upper chamber 61 includes a top plate and a peripheral wall extending downward from the outer edge of the top plate. The top plate of the upper chamber 61 is formed in a disc shape and is large enough to cover the entire surface of the wafer W. The lower chamber 62 includes a bottom wall and a side wall extending upward from the outer edge of the bottom wall. The bottom wall of the lower chamber 62 is formed in a disc shape and is about the same size as the top plate of the upper chamber 61.

[0037] The upper chamber 61 is movably mounted relative to the lower chamber 62. A drive unit, including a cylinder, is connected to the upper chamber 61, and the upper chamber 61 is driven, for example, in the vertical direction by the drive unit. When the upper chamber 61 descends from a state away from the lower chamber 62 to a state approaching the lower chamber 62, a processing space A1 is formed within the chamber 60. When the upper chamber 61 is away from the lower chamber 62, the space within the chamber 60 is open. Even when the processing space A1 is formed, a gap may be provided between the upper chamber 61 and the lower chamber 62.

[0038] The substrate support portion 64 supports the wafer W in the processing space A1. The substrate support portion 64 supports the wafer W horizontally, for example. The substrate support portion 64 is provided on the bottom wall of the lower chamber 62. The substrate support portion 64 may have a function of heating the wafer W. In a plan view (viewed from vertically above), the outer edge of the substrate support portion 64 may be circular. A space is provided between the outer edge of the substrate support portion 64 and the inner edge of the side wall of the lower chamber 62.

[0039] The fluid supply unit 70 supplies a processing fluid containing a predetermined gas to the processing space A1. The fluid supply unit 70 supplies the processing fluid to the processing space A1 while the wafer W is housed in the processing space A1 within the chamber 60. The fluid supply unit 70 may also supply the processing fluid to the processing space A1 via a shower head provided on the top plate of the upper chamber 61. The shower head is configured to disperse and discharge the processing fluid so that it is uniformly supplied to the surface of the wafer W supported by the substrate support unit 64.

[0040] When the substrate processing apparatus 50 applies a processing fluid uniformly to the surface of the wafer W, if the processing fluid does not apply uniformly for any reason, an imbalance in the processing results (for example, a decrease in the uniformity of the pattern width after development) may occur within the plane of the wafer W. Thus, the flow of the processing fluid in the processing space A1 (airflow caused by the processing fluid) can affect the processing results on the wafer W being processed. Therefore, it is useful to monitor the state of the fluid flow in the processing space A1.

[0041] The substrate processing apparatus 50 includes one or more cameras 81 and one or more patterns 82. The number of one or more cameras 81 and the number of one or more patterns 82 may be the same. The substrate processing apparatus 50 illustrated in FIGS. 3 and 4 includes a plurality of cameras 81 (for example, four cameras 81) and a plurality of patterns 82 (four patterns 82). Each of the plurality of cameras 81 corresponds to one pattern 82. First, one camera 81 and one pattern 82 corresponding to the camera 81 will be described.

[0042] The camera 81 is directed toward the processing space A1 within the chamber 60. The camera 81 includes, 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 viewing direction on the image sensor. The image sensor includes a plurality of pixels arranged in a matrix.

[0043] The pattern 82 is disposed within the imaging region of the camera 81. Hereinafter, the imaging region (field of view) of the camera 81 will be referred to as the "imaging region PR". The pattern 82 is provided so as to at least extend within the imaging region PR of the camera 81 and is imaged by the camera 81 through the processing space A1. The pattern 82 changes the image obtained by imaging with the camera 81 by the Schlieren effect. The pattern 82 changes, for example, the image obtained by imaging with the camera 81 in accordance with a change in the refractive index of the fluid in the processing space A1.

[0044] For example, when the refractive index of the fluid in the processing 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 imaged 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 obtained by imaging with 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 processing space A1 can be considered to be caused by the pattern 82.

[0045] The refractive index of a 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 processing space A1 also correlates with the fluid flow in the processing space A1. For example, at a location where there is fluid flow in the processing space A1 (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 where there is no fluid flow in the processing space A1 (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 that enters the camera 81 through the stationary location does not change, while the imaging position of the portion that enters the camera 81 through the flowing location changes. As a result, in the image obtained by the shooting of the camera 81, the state of the fluid flow in the processing space A1 (for example, the distribution of the fluid flow) is visualized as partial fluctuations such as the shape of the pattern 82. Thus, due to the Schlieren effect, the fluctuations of the image generated according to the fluid flow are sharpened by the pattern 82, so that the state such as the distribution of the fluid flow in the processing space A1 can be clearly visualized.

[0046] As illustrated in FIG. 5, the pattern 82 may include a plurality of motifs 83 arranged so as to be dispersed within the shooting area PR (within the visual field) of the camera 81. The fluctuations of the image due to the Schlieren effect are 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.

[0047] For example, the 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 they 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 may be arranged in a honeycomb pattern.

[0048] Motif 83 is a constituent unit of pattern 82. There are no particular restrictions on the shape and size of motif 83. For example, motif 83 may be circular, rectangular, or a polygon such as a hexagon. Multiple motifs 83 may include two or more motifs 83 that differ from each other in at least one of their shapes, sizes, and colors. Multiple motifs 83 may be identical in shape, size, and color. Multiple motifs 83 may be touching each other or separated from each other.

[0049] The multiple motifs 83 may be arranged at a constant pitch or at a non-constant pitch. The pitch is, for example, the distance between centers. For example, when the multiple motifs 83 are arranged in a matrix, the pitch of the multiple motifs 83 in the row direction may be constant, and the pitch of the multiple motifs 83 in the column direction may be constant.

[0050] Multiple motifs 83 and the spaces between multiple motifs 83 may be distinguished by different colors. For example, multiple motifs 83 may be white, and the spaces between multiple motifs 83 may be black. Conversely, multiple motifs 83 may be black, and the spaces between multiple motifs 83 may be white.

[0051] In the pattern 82 illustrated in Figure 5, multiple motifs 83 identical in shape, size, and color are arranged in a matrix at a constant pitch P1. Each of the multiple motifs 83 is rectangular and separated from each other by grid-like lines 84. The multiple motifs 83 and the lines 84 between them are distinguished by different colors. For example, the multiple motifs 83 are white and the lines 84 are black.

[0052] The pattern 82 may be formed by surface irregularities. For example, multiple motifs 83 may be recessed, and the spaces between the multiple motifs 83 may be convex, and the multiple motifs 83 and the spaces between the multiple motifs 83 may be distinguished by the light and dark areas formed by the irregularities. Conversely, multiple motifs 83 may be convex, and the spaces between the multiple motifs 83 may be recessed, and the multiple motifs 83 and the spaces between the multiple motifs 83 may be distinguished. The pattern 82 may be formed by a combination of surface irregularities and colors.

[0053] Returning to Figures 3 and 4, the pattern 82 may be provided to the side of the substrate support portion 64 on the upper surface of the bottom wall of the lower chamber 62. The pattern 82 may also be provided on the upper surface of the bottom wall of the lower chamber 62, between the outer peripheral surface of the substrate support portion 64 and the inner peripheral surface of the side wall of the lower chamber 62. The camera 81 may be positioned to photograph the pattern 82 from above. In one example, the camera 81 (more specifically, the optical system of the camera 81) is positioned vertically above the pattern 82, and the camera 81 is pointed vertically downward. If multiple cameras 81 are provided, each of the multiple cameras 81 is positioned to photograph the corresponding pattern 82 from above.

[0054] Multiple cameras 81 are arranged in a line around the central axis of the chamber 60 (see Figure 4). The central axis of the chamber 60 is, for example, a virtual axis that passes through the center of the top plate of the upper chamber 61 and extends perpendicular to the flat portion of the top surface of the top plate. Multiple cameras 81 may be arranged at equal intervals in the circumferential direction around the central axis of the chamber 60. The imaging area PR of each of the multiple cameras 81 may be set to the side of the wafer W (wafer W supported by the substrate support portion 64) in the processing space A1. In a plan view, a part of the imaging area PR may overlap with the wafer W, and the entire imaging area PR does not have to overlap with the wafer W, as in the example shown in Figure 4.

[0055] As shown in Figure 3, the wafer processing system 1 includes a monitoring device 200. The monitoring device 200 is a device composed of one or more computers. The monitoring device 200 is a device for monitoring the state of fluid flow in the processing space A1 of the substrate processing apparatus 50. The monitoring device 200 generates information indicating the state of fluid flow in the processing space A1 (hereinafter referred to as "state information") based on changes in the images of the pattern 82 captured by each camera 81, for example. The monitoring device 200 may also generate map data representing the distribution of fluid flow as state information in the processing space A1.

[0056] The distribution of fluid flow is, for example, the relationship between the position in processing space A1 (the position in the image captured by camera 81) and the state of the fluid flow (for example, at least one of the flow velocity, flow rate, and flow direction). The distribution of fluid flow may also be the relationship between the position in processing space A1 and the density of the fluid. Due to the Schlieren effect, the fluctuations in the image caused by the fluid flow can be converted into data, enabling filtering or enhancement processing. Therefore, it is effective in visualizing the distribution of fluid flow more clearly.

[0057] The monitoring device 200 has the following functional components (hereinafter referred to as "functional blocks"): an image acquisition unit 211, an image storage unit 212, a state information generation unit 213, and a state display unit 214. The processes performed by these functional blocks correspond to the processes performed by the monitoring device 200.

[0058] The image acquisition unit 211 acquires images obtained by the camera 81 directed towards the processing space A1. The image acquisition unit 211 may acquire images from each of the multiple cameras 81. The images acquired by the image acquisition unit 211 are images generated by the camera 81. The image storage unit 212 stores various images. For example, the image storage unit 212 stores images generated by the state information generation unit 213.

[0059] The state information generation unit 213 generates information (the above state information) indicating the state of fluid flow in the shooting area PR by the camera 81 in the processing space A1, based on the changes in the image acquired by the image acquisition unit 211. The state information generation unit 213 may generate state information for each of the multiple cameras 81 (or generate state information for each shooting area PR). In one example, the state information generation unit 213 generates map data representing the distribution of fluid flow as state information, based on the changes in the image of pattern 82 captured by the camera 81. The main contents of this disclosure will be explained below using the case where map data is generated as state information as an example.

[0060] The state information generation unit 213 may generate map data based on the difference between a reference image captured by camera 81 in the processing space A1 and an evaluation image captured by camera 81 at a timing when the fluid flow distribution is different from the timing when the reference image was captured. By basing the data on the difference between the reference image and the evaluation image, the changes in the pattern 82 image are clarified. This generates map data that more clearly represents the fluid flow distribution in the processing space A1.

[0061] For example, the state information generation unit 213 acquires a reference image from the camera 81 at a predetermined first timing and stores it in the image storage unit 212. Then, the state information generation unit 213 acquires an evaluation image from the camera 81 at a predetermined second timing. The state information generation unit 213 calculates the difference between the reference image stored in the image storage unit 212 and the evaluation image acquired at the second timing. For example, the state information generation unit 213 calculates the difference between the reference image and the evaluation image for each pixel of the camera 81. In one example, the state information generation unit 213 calculates the difference between the pixel value in the reference image and the pixel value in the evaluation image for each pixel. In this case, it is possible to generate high-resolution map data that represents the flow distribution on a pixel-by-pixel basis. The pixel value is, for example, a numerical value representing brightness. For example, the state information generation unit 213 generates matrix data as map data for each pixel of the camera 81 that shows the difference between the pixel value in the reference image and the pixel value in the evaluation image.

[0062] The first timing is predetermined, for example, during a period when no fluid flow occurs in the processing space A1, or when the fluid flow in the processing space A1 is minute. The first timing may also be predetermined during a period when no fluid flow occurs in the processing space A1 toward the wafer W, or when the fluid flow toward the wafer W in the processing space A1 is minute. As an example, the first timing is predetermined during a period when no processing fluid is supplied from the fluid supply unit 70.

[0063] The second timing is predetermined during a period when the fluid flow in the processing space A1 is greater (for example, the flow velocity is higher) compared to the period during which the first timing is determined. The second timing is predetermined during a period when the fluid flow toward the wafer W in the processing space A1 is greater (for example, the flow velocity is higher) compared to the period during which the first timing is determined. As an example, the second timing is predetermined during the period during which the processing fluid is supplied from the fluid supply unit 70.

[0064] As described above, if the second timing (timing for acquiring evaluation images) is set during the period in which the processing fluid is supplied to the processing space A1 from the fluid supply unit 70, the state information generation unit 213 will generate map data representing the distribution of the fluid (gas) flow while the processing fluid is being applied to the wafer W. The map data generated while the processing fluid is being applied to the wafer W is useful for analyzing the influence of the flow state of the processing fluid supplied to the processing space A1 on the processing results of the wafer W.

[0065] Camera 81 may perform shooting so that evaluation images are obtained repeatedly. The state information generation unit 213 may generate map data each time an evaluation image is captured by camera 81. When generating map data repeatedly, the reference image will be used repeatedly. When the reference image is used repeatedly, due to sudden positional shifts of camera 81 or the like, there is a possibility that the conditions that should match between the time the reference image was captured and the time the evaluation image was captured may differ. If such a difference in conditions occurs, it becomes impossible to distinguish whether the difference between the evaluation image and the reference image is due to the difference in conditions or to the flow distribution, which may make it difficult to grasp the flow distribution based on the map data.

[0066] Therefore, the state information generation unit 213 may update the reference image based on multiple evaluation images obtained by the camera 81 repeatedly taking pictures, and generate map data based on the difference between the updated reference image and the evaluation image obtained by taking pictures after the reference image has been updated. Even if the camera 81 experiences a sudden positional shift, the above-mentioned condition difference is kept low by updating the reference image. As a result, it is possible to continue generating map data that makes it easy to understand the flow distribution.

[0067] For example, the state information generation unit 213 may update the reference image based on the evaluation image that has been used (used to generate the map data) each time it generates map data based on the difference between the reference image and the evaluation image. For example, the state information generation unit 213 may generate a new reference image as a weighted average of the reference image and the evaluation image. The respective weights of the reference image and the evaluation image are predetermined by preliminary experiments or the like.

[0068] The status display unit 214 displays the status information generated by the status information generation unit 213 on a display device. The status display unit 214 displays a map image representing the distribution of fluid flow in the processing space A1 on a display device (for example, the display device of the user interface 296 described later) based on the map data as status information. For example, the status display unit 214 generates display data by applying enhancement processing and filtering processing to the map data, and displays the map image based on the display data. For example, the status display unit 214 displays a map image that represents the flow state in colors for each part of the pattern 82 image.

[0069] Figure 6 shows enlarged views of parts of the reference image and evaluation image. (a) is the reference image, and (b) is the evaluation image. As shown in Figure 6, the camera 81 has a plurality of pixels 87. The plurality of pixels 87 are arranged in a matrix with a pitch P2. The arrangement pitch of the plurality of motifs 83 in the image of pattern 82 (the above pitch P1) may be greater than the arrangement pitch of the plurality of pixels 87 (pitch P2).

[0070] In the reference image 300 of Figure 6, the line 84 between motifs 83 is imaged on pixels 87A, 87B, 87C, and 87D, but not on pixels 87E, 87F, 87G, and 87H. In the evaluation image 400 of Figure 6, the image position of line 84 has changed from that of the reference image 300 due to the Schlieren effect. For example, the portion that was imaged on pixel 87C in the reference image 300 now spans both pixels 87C and 87G in the evaluation image 400. Also, the portion that was imaged on pixel 87D in the reference image 300 has completely moved to pixel 87H. In this example, at least for pixels 87C, 87D and pixels 87G, 87H, the difference between the pixel values ​​in the reference image 300 and the pixel values ​​in the evaluation image 400 becomes large. Therefore, it is shown that fluid flow occurs in the region through which the portions imaged on pixels 87C, 87D and pixels 87G, 87H have passed.

[0071] Figure 7 shows a part of the substrate processing apparatus 50 in which the arrangement of the camera 81 differs from the example shown in Figure 3. As shown in Figure 7, the pattern 82 may be provided on a surface F1 that is 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 to the upper surface of the bottom wall of the lower chamber 62 on which the pattern 82 is provided.

[0072] In the example shown in Figure 7, even when multiple motifs 83 are uniform and arranged at a constant pitch, the size of the multiple motifs 83 can be varied in the image of pattern 82. By varying the size of the multiple motifs 83 in the image of pattern 82, the image fluctuations due to the Schlieren effect can be further enhanced.

[0073] Figure 8 is a schematic cross-sectional view showing a modified example of the substrate processing apparatus. The wafer processing system 1 may include a substrate processing apparatus 50A. The substrate processing apparatus 50A differs from the substrate processing apparatus 50 in the placement of the camera 81 and the pattern 82. In the substrate processing apparatus 50A, the pattern 82 is photographed by the camera 81 after passing through the space above the wafer W supported by the substrate support portion 64 in the processing space A1. For example, the camera 81 is provided on the inner surface of the peripheral wall of the upper chamber 61. The pattern 82 is provided on the inner surface of the peripheral wall of the upper chamber 61 so as to face the camera 81. Two or more sets of cameras 81 and patterns 82 may be provided on the inner surface of the peripheral wall of the upper chamber 61.

[0074] Figure 9 is a schematic cross-sectional view showing another modification of the substrate processing apparatus. The wafer processing system 1 may also include a substrate processing apparatus 50B. The substrate processing apparatus 50B differs from the substrate processing apparatus 50A in that it has a projection apparatus 88 instead of a pattern 82.

[0075] The projection device 88 projects the pattern 82 onto a projection surface F2. Surface F2 is positioned to extend within the field of view of the camera 81 and to be photographed by the camera 81 via the processing space A1. The projection device 88 may be configured to project the pattern 82 onto surface F2 via the processing space A1. For example, the projection device 88 is positioned near the camera 81 and projects the pattern 82 onto opposing positions with the central axis of the chamber 60 in between. Providing a projection device 88 that projects the pattern 82 onto a surface F2 prepared for projection, instead of providing the pattern 82, is also included in providing the pattern 82.

[0076] The projection device 88 makes it easier to install the pattern 82 compared to permanently installing the pattern 82. It also suppresses deterioration of the pattern 82 due to processing fluids, etc.

[0077] The projection device 88 may project the pattern 82 onto surface F2 via the space A31 between the area on surface F2 where the pattern 82 is projected and the camera 81. The light emitted from the projection device 88 is refracted twice: once when passing through space A31 toward surface F2 and again when passing through space A31 toward camera 81. As a result, the change in pixel values ​​due to refraction is larger compared to when the camera 81 photographs a pattern 82 fixed to surface F2. Therefore, map data that represents the flow distribution with higher sensitivity can be generated.

[0078] For example, the projection device 88 may project the pattern 82 onto the surface F2 via the space within the field of view of the camera 81. The projection device 88 may be arranged such that the light from the projection device 88 toward the surface F2 and the light from the surface F2 toward the camera 81 pass through a common space A31. The angle 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, 20° or less, or 10° or less.

[0079] The camera 81 may be fixed to the projection device 88. Fixing the camera 81 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 the example shown in Figure 9, the camera 81 is placed on the projection device 88 fixed to the peripheral wall of the upper chamber 61, 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 image fluctuations due to the Schlieren effect can be further clarified.

[0080] Surface F2 may have a color tone and texture that enhances the clarity of the pattern 82 projected by the projection device 88. Surface F2 may be formed by attaching a sheet to the peripheral wall of the upper chamber 61, or by painting or processing the peripheral wall of the upper chamber 61 itself.

[0081] The arrangement of the camera 81 and pattern 82 is not limited to the arrangement exemplified above, and can be changed in any way as long as the pattern 82 can be photographed by the camera 81 through the processing space A1. In the substrate processing apparatus 50 exemplified in Figures 3 and 4, instead of the pattern 82, a projection device 88 capable of projecting the pattern 82 may be provided corresponding to each of the multiple cameras 81. The camera 81 may be located outside the chamber 60 or inside the wall. The camera 81 may photograph the shooting area PR (pattern 82) through a transparent window provided in the chamber 60.

[0082] The monitoring device 200 may be configured to perform at least one of filtering and enhancement processing of map data using a two-dimensional orthogonal polynomial. As shown in Figure 10, the monitoring device 200 may include, as functional blocks, a map generation unit 213A, an expansion unit 221, a coefficient modification unit 222, a reconstruction unit 223, and a map display unit 214A. The map generation unit 213A is a type of state information generation unit 213, and the map display unit 214A is a type of state display unit 214.

[0083] The expansion unit 221 expands the map data into a series of multiple components, each represented by a two-dimensional orthogonal polynomial. For example, each of the multiple components is matrix data with the same number of rows and columns as the map data. The series represents data obtained by weighting the multiple components together. The weights (coefficients) of each of the multiple components are determined so that the sum of them matches the map data.

[0084] The coefficient modification unit 222 modifies the coefficient of one or more components to be modified among multiple components in the series. For example, if the purpose is filtering, one or more components to be reduced by filtering are the one or more components to be modified, and the coefficient modification unit decreases the coefficient of that one or more components to be modified. If the purpose is enhancement, one or more components to be increased by enhancement are the one or more components to be modified, and the coefficient modification unit increases the coefficient of that one or more components to be modified.

[0085] The reconstruction unit 223 reconstructs the map data based on a series in which the coefficients of one or more components to be changed have been modified. For example, the reconstruction unit 223 reconstructs the map data by adding up multiple components with weights.

[0086] A two-dimensional orthogonal polynomial is a two-dimensional Legendre polynomial. Figure 11 is a schematic diagram illustrating multiple components, each of which is a two-dimensional Legendre polynomial. The multiple components include LP0, which does not constitute a pattern; LP1, which constitutes a vertical stripe pattern; LP2, which constitutes a horizontal stripe pattern; and LP3, which is a combination of the vertical and horizontal stripe patterns.

[0087] For example, if fluid flow tends to occur along the vertical direction, the coefficient changing unit 222 may designate at least one of the multiple components LP1 as one or more components to be changed and increase the coefficient of that one or more components to be changed. This makes it easier to emphasize the distribution of fluid flow. Alternatively, the coefficient changing unit 222 may designate at least one of the multiple components LP2 as one or more components to be changed and decrease the coefficient of that one or more components to be changed. This reduces horizontal stripe patterns that are not closely related to fluid flow, making it easier to understand the distribution of fluid flow.

[0088] Two-dimensional orthogonal polynomials are not necessarily limited to two-dimensional Legendre polynomials. For example, a two-dimensional orthogonal polynomial could be a two-dimensional Chebyshev polynomial.

[0089] Figure 12 is a block diagram illustrating the hardware configuration of the monitoring device 200. As shown in Figure 12, the monitoring device 200 has a circuit 290. The circuit 290 includes a processor 291, a memory 292, a storage 293, an image processing circuit 294, an on / off circuit 295, and a user interface 296.

[0090] The storage 293 includes, for example, one or more non-volatile storage media. Examples of non-volatile storage media include hard disk drives, solid-state drives, and flash memory. The non-volatile storage media may also include portable storage media such as optical discs. The storage 293 stores a monitoring program that causes the monitoring device 200 to acquire images obtained by the camera 81 directed towards the processing space A1, and to generate information (state information) indicating the state of fluid flow in the camera 81's imaging area PR within the processing space A1 based on changes in the images. For example, the storage 293 stores a monitoring program that causes the monitoring device 200 to configure each of the above-described functional blocks.

[0091] Memory 292 includes one or more volatile storage media. An example of a volatile storage media is random access memory. Memory 292 temporarily stores programs loaded from storage 293. Processor 291 includes one or more computing devices. An example of a computing device is a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). Processor 291 executes the programs loaded into memory 292, thereby configuring each of the above-mentioned functional blocks in the monitoring device 200. Processor 291 may temporarily store the calculation results in memory 292.

[0092] The image processing circuit 294 causes the camera 81 to take a picture 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 input devices include keyboards or mice. Examples of display devices include liquid crystal monitors. The input devices may be incorporated into the display devices to form a touch panel. The user interface 296 outputs input to one or more input devices and displays text and images on one or more display devices in response to a request from the processor 291.

[0093] The monitoring device 200 may be incorporated into the control device 100, or it may be incorporated into hardware separate from the control device 100. A network line, such as a wide area network or a local area network, may be interposed between the monitoring device 200 and the substrate processing devices 50, 50A, and 50B.

[0094] [Monitoring Method] Next, as an example of a monitoring method, a visualization procedure performed by a monitoring device 200 in a wafer processing system 1 equipped with a substrate processing device 50 will be illustrated. This visualization procedure includes acquiring an image obtained by taking a picture with a camera 81 directed towards the processing space A1, and generating state information (e.g., map data) indicating the state of fluid flow in the area PR captured by the camera 81 within the processing space A1, based on the changes in the above image.

[0095] Figure 13 is a flowchart illustrating the visualization procedure. As shown in Figure 13, the monitoring device 200 first executes steps S01, S02, S03, and S04. In step S01, for example, the image acquisition unit 211 waits for the first timing. In step S02, for example, the image acquisition unit 211 causes each camera 81 to start shooting video to generate a reference image. In step S03, for example, the image acquisition unit 211 waits for a predetermined time to elapse. In step S04, for example, the state information generation unit 213 generates a reference image for each camera 81 based on a plurality of still images that constitute the video captured by the camera 81. In one example, the state information generation unit 213 generates a reference image by averaging the plurality of still images and stores it in the image storage unit 212. As a result, a reference image is acquired for each camera 81 (for each shooting area PR).

[0096] Next, the monitoring device 200 executes steps S05, S06, S07, and S08. In step S05, for example, the image acquisition unit 211 waits for the second timing. In step S06, for example, the image acquisition unit 211 causes each camera 81 to start shooting video to generate evaluation images. In step S07, for example, the image acquisition unit 211 waits for a predetermined time to elapse. In step S08, for example, the state information generation unit 213 generates evaluation images based on a plurality of still images that constitute the video captured by the cameras 81. In one example, the state information generation unit 213 generates evaluation images by averaging the plurality of still images and stores them in the image storage unit 212. As a result, an evaluation image is acquired for each camera 81 (for each shooting area PR).

[0097] Next, the monitoring device 200 executes steps S11, S12, and S13. In step S11, for example, the state information generation unit 213 generates map data based on the difference between the reference image and the evaluation image. In step S12, for example, the state information generation unit 213 performs enhancement processing on the map data. Enhancement processing is, for example, a process that amplifies the difference in pixel values ​​between pixels. In step S13, for example, the state information generation unit 213 performs filtering processing on the map data. Filtering processing is a process that removes values ​​caused by noise from the pixel values. The execution order of enhancement processing and filtering processing is not limited to this, and the state information generation unit 213 may perform enhancement processing after filtering processing.

[0098] Next, the monitoring device 200 executes step S14. In step S14, for example, the status display unit 214 displays the map image on the display device based on the map data after enhancement and filtering. This completes the visualization procedure.

[0099] In one example, the monitoring device 200 records map data for each location where the camera 81's shooting area PR is set. When an abnormality occurs in the processing result by the substrate processing device 50, the cause of the abnormality can be estimated by checking the map data for each shooting area PR. For example, when the chamber 60 is closed, a gap may be created between the upper chamber 61 and the lower chamber 62 to form the processing space A1. In this case, if the degree of the gap differs in some areas from other areas, the difference between the map data for each shooting area PR will be large. Even when the chamber 60 is sealed to form the processing space A1, if leakage occurs in some areas due to insufficient sealing, the difference between the map data for each shooting area PR will be large. Such differences in map data make it possible to estimate the cause of the abnormality.

[0100] Figure 14 is a flowchart showing a modified visualization procedure, which differs from the flowchart in Figure 13 in that it repeats the generation of evaluation images and the generation of map data. In the flowchart in Figure 14, steps S01 to S08 and S11 to S14 are the same as steps S01 to S08 and S11 to S14 in the flowchart in Figure 13.

[0101] In the flowchart shown in Figure 14, the monitoring device 200 displays the map image in step S14, and then executes step S15. In step S15, for example, the state information generation unit 213 updates the reference image for each camera 81 (shooting area PR). In one example, the state information generation unit 213 generates a new reference image by taking a weighted average of the evaluation image generated in step S08 and the reference image, and stores it in the image storage unit 212.

[0102] Next, the monitoring device 200 executes step S16. In step S16, for example, the image acquisition unit 211 waits for a predetermined period to elapse from the start of step S06. After that, the monitoring device 200 returns to step S06. As a result, a series of processes including the generation of evaluation images, the generation of map data, the display of map images, and the updating of reference images are repeatedly executed at the predetermined period.

[0103] [Other] In the above example, the state information generation unit 213 generates map data. Instead of map data, the state information generation unit 213 may generate information as the state information indicating at least one of the flow velocity, flow rate, and flow direction for each shooting area PR corresponding to the camera 81 within a certain range or at a specific location.

[0104] The monitoring device 200 may perform an adjustment process to adjust one or more parameters that define the conditions for processing (or operation) performed by the substrate processing device 50, etc., based on state information (e.g., map data) for each imaging area PR. Examples of one or more parameters include the flow rate of the processing fluid and the supply time of the processing fluid. The adjustment process may include autonomous adjustment by the monitoring device 200 itself, suggestion of parameter adjustment amounts, and display of the fact that parameter adjustment is possible. The monitoring device 200 may perform the above adjustment process when there is a large difference in state information for each imaging area PR. By performing such an adjustment process, an opportunity to adjust the parameters is provided.

[0105] In one of the various examples described above, at least some of the matters described in the other examples may be combined. For example, in the substrate processing apparatus 50, in addition to the multiple cameras 81 and multiple patterns 82, the cameras 81 and patterns 82 in the substrate processing apparatus 50A may be provided.

[0106] [Summary of this disclosure] This disclosure includes the following components [1] to

[17] .

[0107] [1] A monitoring device (200) comprising: an image acquisition unit (211) that acquires an image obtained by taking a picture with a camera (81) pointed towards a processing space (A1) in which a substrate (W) is housed and a substrate processing fluid (processing fluid) is supplied; and a state information generation unit (213) that generates information (state information) indicating the state of the fluid flow in the camera (81) area (PR) of the processing space (A1) based on the changes in the image. The state information is based on the changes in the image that occur in accordance with the fluid flow due to the Schlieren effect, and therefore reflects the state of the flow of the processing fluid in the processing space (A1). Therefore, by using the monitoring device (200), the state of the processing fluid in the processing space (A1) can be easily grasped.

[0108] [2] The monitoring device (200) described in [1] above generates the above information (state information) based on the difference between a reference image (300) taken by a camera (81) of the processing space (A1) and an evaluation image (400) taken by the camera (81) at a time when the state of the processing space (A1) is different from the time when the reference image (300) was taken. In this case, by basing the information on the difference between the reference image (300) and the evaluation image (400), changes in the image caused by the fluid flow are made clearer. Therefore, it is possible to generate state information that clearly represents the state of the fluid flow in the processing space (A1).

[0109] [3] The monitoring device (200) described in [2] above, wherein the camera (81) has a plurality of pixels (87), and the state information generation unit (213) generates the above information (state information) based on the difference between the pixel value of each of the plurality of pixels (87) in the evaluation image (400) and the pixel value in the reference image (300). In this case, state information that more clearly represents the state of fluid flow in the processing space (A1) can be generated.

[0110] [4] A monitoring device (200) according to any one of [1] to [3] above, wherein a pattern (82) is arranged within the shooting area (PR) of the camera (81) and is captured via the processing space (A1), and the state information generation unit (213) generates the above information (state information) based on the changes in the pattern (82) in the image. In this case, the image fluctuations caused by the fluid flow are clarified by the pattern 82, so that map data that clearly represents the distribution of fluid flow in the processing space (A1) is generated. Therefore, the distribution of fluid flow in the processing space (A1) can be easily visualized.

[0111] [5] The monitoring device (200) described in [4] above, wherein the pattern (82) includes a plurality of motifs (83) arranged to be dispersed within the shooting area (PR) of the camera (81). In this case, the image fluctuations due to the Schlieren effect are further enhanced by the plurality of motifs 83. Therefore, the distribution of fluid flow in the processing space (A1) can be visualized more clearly.

[0112] [6] The monitoring device (200) described in [5] above, wherein the camera (81) has a plurality of pixels (87), and the array pitch (P1) of the plurality of motifs (83) in the image of the pattern (82) is greater than the array pitch (P2) of the plurality of pixels (87). In this case, the generation of moiré (interference fringes) can be suppressed.

[0113] [7] The monitoring device (200) described in any one of [1] to [6] above, wherein the image acquisition unit (211) acquires the above images from each of the multiple cameras (81), the state information generation unit (213) generates the above information (state information) for each of the multiple cameras (81), and the shooting area (PR) of each of the multiple cameras (81) is set to the side of the substrate (W) in the processing space (A1). In this case, by looking at the difference in state information for each shooting area (PR), it is possible to determine whether the flow of the processing fluid in the processing space (A1) is in an appropriate state.

[0114] [8] The monitoring device (200) described in [7] above, wherein the patterns (82) are provided to correspond to each of the multiple cameras (81), and each of the multiple cameras (81) is positioned to photograph the corresponding pattern (82) from above. In this case, the state of the processing fluid flowing outward from the center of the substrate (W) is easily reflected in the state information.

[0115] [9] A monitoring method comprising: acquiring an image obtained by taking a picture with a camera (81) directed towards a processing space (A1) in which a substrate processing fluid (processing fluid) is supplied while a substrate (W) is contained; and generating information (state information) indicating the state of the fluid flow in the area (PR) captured by the camera (81) within the processing space (A1) based on the changes in the image. This monitoring method, like the monitoring device (200) described in [1] above, makes it easy to grasp the state of the processing fluid in the processing space (A1).

[0116]

[10] The monitoring method described in [9] above, wherein generating the above information (state information) includes generating the above information (state information) based on the difference between a reference image (300) taken by a camera (81) of the processing space (A1) and an evaluation image (400) taken by the camera (81) at a time when the state of the processing space (A1) is different from the time when the reference image (300) was taken. In this case, similar to the monitoring device (200) described in [2] above, it is possible to generate state information that clearly represents the state of fluid flow in the processing space (A1).

[0117]

[11] The monitoring method according to

[10] above, wherein the camera (81) has a plurality of pixels (87), and generating the above information (state information) includes generating the above information (state information) based on the difference between the pixel value of each of the plurality of pixels (87) in the evaluation image (400) and the pixel value in the reference image (300). In this case, similar to the monitoring device (200) described in [3] above, it is possible to generate state information that more clearly represents the state of fluid flow in the processing space (A1).

[0118]

[12] A monitoring method according to any one of [9] to

[11] above, wherein a pattern (82) is arranged within the shooting area (PR) of the camera (81) and is captured via the processing space (A1), and generating the above information (state information) includes generating the above information (state information) based on changes in the pattern (82) in the above image. In this case, similar to the monitoring device (200) described in [4] above, the distribution of fluid flow in the processing space (A1) can be easily visualized.

[0119]

[13] The monitoring method according to

[12] , wherein the pattern (82) includes a plurality of motifs (83) arranged to be dispersed within the shooting area (PR) of the camera (81). In this case, similar to the monitoring device (200) described in [5], the distribution of fluid flow in the processing space (A1) can be visualized more clearly.

[0120]

[14] The monitoring method according to

[13] , wherein the camera (81) has a plurality of pixels (87), and the array pitch (P1) of the plurality of motifs (83) in the image of the pattern (82) is greater than the array pitch (P2) of the plurality of pixels (87). In this case, the generation of moiré (interference fringes) can be suppressed, similar to the monitoring device (200) described in [6].

[0121]

[15] The monitoring method according to any one of [9] to

[14] above, wherein acquiring the above image includes acquiring the above image from each of a plurality of cameras (81), including camera (81), generating the above information (state information) includes generating the above information (state information) for each of the plurality of cameras (81), and the shooting area (PR) of each of the plurality of cameras (81) is set to the side of the substrate (W) in the processing space (A1). In this case, similar to the monitoring device (200) described in [7] above, it is possible to determine whether the flow of the processing fluid in the processing space (A1) is in an appropriate state by looking at the difference in state information for each shooting area (PR).

[0122]

[16] The monitoring method according to

[15] , wherein the patterns (82) are provided to correspond to each of the multiple cameras (81), and each of the multiple cameras (81) is positioned to photograph the corresponding pattern (82) from above. In this case, similar to the monitoring device (200) described in [8], the state of the processing fluid flowing outward from the center of the substrate (W) is easily reflected in the state information.

[0123]

[17] A monitoring program that causes the apparatus (200) to perform the following actions: acquire an image obtained by taking a picture with a camera (81) pointed towards a processing space (A1) in which a fluid for processing the substrate (processing fluid) is supplied while the substrate (W) is contained; and generate information (state information) indicating the state of the fluid flow in the area (PR) of the processing space (A1) captured by the camera (81) based on the changes in the above image. Similar to the monitoring device (200) described in [1] above, this monitoring program makes it easy to grasp the state of the processing fluid in the processing space (A1).

[0124] 1...Wafer processing system, W...Wafer, 50, 50A, 50B...Substrate processing device, A1...Processing space, 60...Chamber, 70...Fluid supply unit, 81...Camera, 82...Pattern, 83...Motif, 87...Pixel, 211...Image acquisition unit, 213...State information generation unit, 213A...Map generation unit, 300...Reference image, 400...Evaluation image.

Claims

1. A monitoring device comprising: an image acquisition unit that acquires an image obtained by taking a picture with a camera directed towards a processing space in which a substrate processing fluid is supplied while a substrate is housed; and a state information generation unit that generates information indicating the state of fluid flow in the area of ​​the processing space captured by the camera based on changes in the image.

2. The monitoring device according to claim 1, wherein the state information generation unit generates the information based on the difference between a reference image of the processing space captured by the camera and an evaluation image captured by the camera at a time when the state of the processing space is different from the time the reference image was captured.

3. The monitoring device according to claim 2, wherein the camera has a plurality of pixels, and the state information generation unit generates the information based on the difference between the pixel value of each of the plurality of pixels in the evaluation image and the pixel value in the reference image.

4. A pattern is arranged within the shooting area of ​​the camera, which is captured via the processing space, and the state information generation unit generates the information based on the change in the pattern in the image, according to any one of claims 1 to 3.

5. The monitoring device according to claim 4, wherein the pattern includes a plurality of motifs arranged to be dispersed within the shooting area of ​​the camera.

6. The monitoring device according to claim 5, wherein the camera has a plurality of pixels, and the array pitch of the plurality of motifs in the pattern image is greater than the array pitch of the plurality of pixels.

7. The monitoring device according to claim 4, wherein the image acquisition unit acquires images from each of the plurality of cameras, including the camera, the state information generation unit generates the information for each of the plurality of cameras, and the shooting area of ​​each of the plurality of cameras is set to the side of the substrate in the processing space.

8. The monitoring device according to claim 7, wherein the pattern is provided to correspond to each of the plurality of cameras, and each of the plurality of cameras is positioned to photograph the corresponding pattern from above.

9. A monitoring method comprising: acquiring an image obtained by taking a picture with a camera pointed towards a processing space in which a fluid for processing the substrate is supplied while the substrate is contained; and generating information indicating the state of fluid flow in the area of ​​the processing space captured by the camera based on changes in the image.

10. The monitoring method according to claim 9, wherein generating the information includes generating the information based on the difference between a reference image of the processing space captured by the camera and an evaluation image captured by the camera at a time when the state of the processing space is different from the time the reference image was captured.

11. The monitoring method according to claim 10, wherein the camera has a plurality of pixels, and generating the information includes generating the information based on the difference between the pixel value of each of the plurality of pixels in the evaluation image and the pixel value in the reference image.

12. A monitoring method according to any one of claims 9 to 11, wherein a pattern is arranged within the shooting area of ​​the camera, and generating the information includes generating the information based on changes in the pattern in the image.

13. The monitoring method according to claim 12, wherein the pattern includes a plurality of motifs arranged to be dispersed within the shooting area of ​​the camera.

14. The monitoring method according to claim 13, wherein the camera has a plurality of pixels, and the array pitch of the plurality of motifs in the pattern image is greater than the array pitch of the plurality of pixels.

15. The monitoring method according to claim 12, wherein acquiring the image includes acquiring the image from each of a plurality of cameras, including the camera, generating the information includes generating the information for each of the plurality of cameras, and the shooting area of ​​each of the plurality of cameras is set to the side of the substrate in the processing space.

16. The monitoring method according to claim 15, wherein the pattern is provided to correspond to each of the plurality of cameras, and each of the plurality of cameras is positioned to photograph the corresponding pattern from above.

17. A monitoring program that causes the device to perform the following actions: acquire an image obtained by taking a picture with a camera pointed towards a processing space in which a fluid for processing the substrate is supplied while the substrate is contained; and generate information indicating the state of the fluid flow in the area of ​​the processing space captured by the camera, based on changes in the image.

Images