PCB inspection apparatus, PCB inspection method, and PCB inspection program

Abstract

This technology provides the acquisition of images that can detect defects in circuit boards with higher accuracy. [Solution] A substrate inspection apparatus for inspecting a substrate using an image of the substrate's surface, comprising: a holding unit 31 for holding the substrate; a first light source unit 51 for emitting visible light to the substrate held by the holding unit 31; a second light source unit 52 for emitting infrared light to the substrate held by the holding unit 31; a first imaging sensor for receiving first reflected light emitted from the substrate by irradiating it with visible light and capturing a visible light image of the substrate's surface; and a second imaging sensor for receiving second reflected light emitted from the substrate by irradiating it with infrared light and capturing an infrared light image of the substrate's surface.

Description

Technical Field

[0001] The present disclosure relates to a substrate inspection apparatus, a substrate inspection method, and a substrate inspection program.

Background Art

[0002] Patent Document 1 describes that by irradiating a substrate with near-infrared light and imaging, the roughness component of the surface of the substrate is removed to obtain an image of a defective portion.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides a technique for acquiring an image capable of detecting defects on a substrate with higher accuracy.

Means for Solving the Problems

[0005] A substrate inspection apparatus according to an aspect of the present disclosure is a substrate inspection apparatus that inspects a substrate using an image obtained by imaging the surface of the substrate, and includes a holding unit that holds the substrate, a first light source unit that emits visible light to the substrate held by the holding unit, a second light source unit that emits infrared light to the substrate held by the holding unit, a first imaging sensor that receives first reflected light emitted from the substrate by irradiating the visible light and images a visible light image related to the surface of the substrate, and a second imaging sensor that receives second reflected light emitted from the substrate by irradiating the infrared light and images an infrared light image related to the surface of the substrate.

Effects of the Invention

[0006] According to this disclosure, a technology is provided for acquiring images that can detect defects in a substrate with higher accuracy. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a schematic diagram showing an example of the general configuration of a substrate processing system. [Figure 2] Figure 2 is a schematic diagram showing an example of a coating and developing apparatus. [Figure 3] Figure 3 is a schematic diagram showing an example of an imaging unit. [Figure 4] Figure 4 is a schematic diagram illustrating an example of the arrangement of the imaging unit and the light-emitting / reflecting unit in an imaging unit. [Figure 5] Figure 5 shows an example of the optical properties of an optical filter. [Figure 6] Figure 6 is a block diagram showing an example of the functional configuration of a control device. [Figure 7] Figure 7(a) illustrates an example of an image acquired by the control device, and Figure 7(b) illustrates an example of a method for creating a pseudo-RGB image. [Figure 8] Figure 8 is a block diagram showing an example of the hardware configuration of a control device. [Figure 9] Figure 9 is a flowchart illustrating an example of a substrate inspection method. [Modes for carrying out the invention]

[0008] Various exemplary embodiments will be described below.

[0009] In one exemplary embodiment, a substrate inspection apparatus is provided. The substrate inspection apparatus is a substrate inspection apparatus that inspects a substrate using an image of the surface of the substrate, and comprises: a holding unit for holding the substrate; a first light source unit that emits visible light to the substrate held in the holding unit; a second light source unit that emits infrared light to the substrate held in the holding unit; a first imaging sensor that receives first reflected light emitted from the substrate by irradiating it with the visible light and captures a visible light image of the surface of the substrate; and a second imaging sensor that receives second reflected light emitted from the substrate by irradiating it with the infrared light and captures an infrared light image of the surface of the substrate.

[0010] In the above-described substrate inspection apparatus, a visible light image of the substrate surface is acquired by the first imaging sensor, and an infrared image of the substrate surface is acquired by the second imaging sensor. Therefore, the substrate can be inspected using these two types of images. The visible light image and the infrared light image contain different information for detecting defects in the substrate, and using these images for inspection allows for obtaining more detailed information about the substrate. Consequently, the above-described substrate inspection apparatus makes it possible to acquire images that can detect defects in the substrate with higher accuracy.

[0011] The system may further include a direction-changing unit that changes the direction of the first reflected light and the second reflected light to the same direction, wherein the first image sensor receives the first reflected light whose direction has been changed by the direction-changing unit, and the second image sensor receives the second reflected light whose direction has been changed by the direction-changing unit.

[0012] With the above configuration, the arrangement of the first and second imaging sensors can be changed more flexibly compared to a configuration without a direction-changing section.

[0013] The first and second imaging sensors may be housed in the same camera.

[0014] By adopting the configuration using the camera that houses the first imaging sensor and the second imaging sensor as described above, it is possible to acquire visible light images and infrared light images with a single camera, thus preventing the substrate inspection apparatus from becoming large-sized.

[0015] It may also be an aspect further having an incident direction adjustment unit that adjusts the visible light from the first light source unit and the infrared light from the second light source unit so as to have the same incident direction with respect to the substrate.

[0016] With the above configuration, the arrangement of the first light source unit and the second light source unit can be flexibly changed as compared with the case where there is no incident direction adjustment unit.

[0017] The visible light incident on the substrate, the infrared light incident on the substrate, the first reflected light emitted from the substrate, and the second reflected light emitted from the substrate may be on the same optical axis.

[0018] By configuring the above four lights to be arranged on the same optical axis, the space where the optical axes of these lights exist can be reduced. Therefore, restrictions related to the device configuration, such as making the device configuration such that it does not block the optical path of the light, can be reduced, and thus the arrangement of members other than the optical system can be flexibly changed.

[0019] The holding unit, the first light source unit, the second light source unit, the first imaging sensor, and the second imaging sensor may be housed in an imaging unit, and further have a control unit that controls the imaging unit to perform imaging of the visible light image by the first imaging sensor and imaging of the infrared light image by the second imaging sensor, and perform inspection related to the substrate using the visible light image and the infrared light image.

[0020] With the above configuration, the control unit can comprehensively control imaging of the visible light image and the infrared light image and inspection related to the substrate using these images.

[0021] The holding portion may be movable horizontally within the imaging unit, and under control by the control unit, the acquisition of the visible light image by the first imaging sensor and the acquisition of the infrared light image by the second imaging sensor may be performed in parallel while the holding portion is moving.

[0022] By adopting the above configuration, the time required to capture visible light and infrared light images can be reduced, thereby shortening the time required for inspecting the substrate.

[0023] The control unit may also detect defects on the surface of the substrate by comparing the visible light image with the infrared light image.

[0024] The information regarding defects in the substrate contained in the visible light image and the information regarding defects in the substrate contained in the infrared light image are not identical and may contain different information. Therefore, by configuring the system to detect defects by comparing the two images, it becomes possible to detect defects that cannot be detected by one image alone.

[0025] The visible light image is an image obtained by combining multiple types of color component images that have different color components from each other, and the control unit may cause the display unit to display an image obtained by combining the infrared light image and at least one of the multiple types of color component images.

[0026] With the above configuration, a composite image different from a normal visible light image or infrared light image is displayed on the display unit, allowing the user to view a different type of image than a normal visible light image or infrared light image.

[0027] In another exemplary embodiment, a substrate inspection method is provided. The substrate inspection method is a substrate inspection method that inspects a substrate using an image of the surface of the substrate, and includes: holding the substrate with a holding unit; emitting visible light from a first light source unit to the substrate held by the holding unit; emitting infrared light from a second light source unit to the substrate held by the holding unit; receiving first reflected light emitted from the substrate by irradiating it with the visible light with a first image sensor to capture a visible light image of the surface of the substrate; and receiving second reflected light emitted from the substrate by irradiating it with the infrared light with a second image sensor to capture an infrared light image of the surface of the substrate.

[0028] In the above substrate inspection method, a visible light image of the substrate surface is acquired by the first imaging sensor, and an infrared image of the substrate surface is acquired by the second imaging sensor. Therefore, the substrate can be inspected using these two types of images. The visible light image and the infrared light image contain different information for detecting defects in the substrate, and using these images for inspection allows for obtaining more detailed information about the substrate. Consequently, the above substrate inspection method makes it possible to acquire images that can detect defects in the substrate with higher accuracy.

[0029] The method further includes changing the direction of the first reflected light and the second reflected light to the same direction by the direction changing unit, and in capturing the visible light image, the first imaging sensor may receive the first reflected light whose direction has been changed by the direction changing unit, and in capturing the near-infrared light image, the second imaging sensor may receive the second reflected light whose direction has been changed by the direction changing unit.

[0030] With the above configuration, the arrangement of the first and second imaging sensors can be changed more flexibly compared to the case where the direction is not changed by the direction changing unit.

[0031] The first and second imaging sensors may be housed in the same camera.

[0032] As described above, by using a camera that houses both the first and second imaging sensors, it is possible to acquire both visible light and infrared light images with a single camera, thus preventing the equipment used for substrate inspection from becoming too large.

[0033] The embodiment may further include adjusting the visible light from the first light source and the infrared light from the second light source so that they are incident in the same direction to the substrate using an incident direction adjustment unit.

[0034] With the above configuration, the arrangement of the first and second light sources can be changed more flexibly compared to the case where adjustment is not performed by the incident direction adjustment unit.

[0035] The visible light incident on the substrate, the infrared light incident on the substrate, the first reflected light emitted from the substrate, and the second reflected light emitted from the substrate may be configured to lie on the same optical axis.

[0036] By arranging the four lights described above on the same optical axis, the space in which these light axes exist can be reduced. Therefore, it is possible to reduce restrictions on the device configuration, such as configuring the device in a way that does not obstruct the path of light, and thus the arrangement of components other than the optical system can be flexibly changed.

[0037] The holding unit, the first light source unit, the second light source unit, the first image sensor, and the second image sensor are housed in an imaging unit, and the control unit controls the imaging unit to capture the visible light image with the first image sensor and the infrared light image with the second image sensor, and the control unit further includes performing an inspection of the substrate using the visible light image and the infrared light image.

[0038] With the above configuration, the control unit can comprehensively control the acquisition of visible light and infrared light images, as well as the inspection of the substrate using these images.

[0039] The holding portion may be movable horizontally within the imaging unit, and under control by the control unit, the acquisition of the visible light image by the first imaging sensor and the acquisition of the infrared light image by the second imaging sensor may be performed in parallel while the holding portion is moving.

[0040] By adopting the above configuration, the time required to capture visible light and infrared light images can be reduced, thereby shortening the time required for inspecting the substrate.

[0041] In performing the inspection, the control unit may detect defects on the surface of the substrate by comparing the visible light image with the infrared light image.

[0042] The information regarding defects in the substrate contained in the visible light image and the information regarding defects in the substrate contained in the infrared light image are not identical and may contain different information. Therefore, by configuring the system to detect defects by comparing the two images, it becomes possible to detect defects that cannot be detected by one image alone.

[0043] The visible light image is an image obtained by combining multiple types of color component images that have different color components from each other, and the configuration may further include the control unit displaying an image obtained by combining the infrared light image and at least one of the multiple types of color component images to the display unit.

[0044] With the above configuration, a composite image different from a normal visible light image or infrared light image is displayed on the display unit, allowing the user to view a different type of image than a normal visible light image or infrared light image.

[0045] In another exemplary embodiment, a substrate inspection program is provided. The substrate inspection program is a program for a substrate inspection apparatus that causes a computer to perform an inspection of a substrate using an image of the substrate's surface, and causes the computer to perform the following actions: hold the substrate with a holding unit; emit visible light from a first light source to the substrate held by the holding unit; emit infrared light from a second light source to the substrate held by the holding unit; receive first reflected light emitted from the substrate by the irradiation of the visible light with a first image sensor to capture a visible light image of the substrate's surface; and receive second reflected light emitted from the substrate by the irradiation of the infrared light with a second image sensor to capture an infrared light image of the substrate's surface.

[0046] The above circuit board inspection program achieves the same effect as the circuit board inspection method.

[0047] Various exemplary embodiments will be described in detail below with reference to the drawings. In each drawing, the same or corresponding parts will be denoted by the same reference numerals.

[0048] [Circuit board processing system]

[0049] The substrate processing system 1 is a system that performs the following processes on a workpiece W: formation of a photosensitive film, exposure of the photosensitive film, and development of the photosensitive film. The workpiece W to be processed is, for example, a substrate, or a substrate in which a film or circuit has been formed by a predetermined process. The substrate is, as an example, a silicon wafer. The workpiece W (substrate) may be circular. The workpiece W may also be a glass substrate, a mask substrate, or an FPD (Flat Panel Display). The photosensitive film is, for example, a resist film.

[0050] As shown in Figures 1 and 2, the substrate processing system 1 comprises a coating / developing apparatus 2 and an exposure apparatus 3. The exposure apparatus 3 performs exposure processing on a resist film (photosensitive film) coated on a workpiece W (substrate). Specifically, the exposure apparatus 3 irradiates the portion of the resist film to be exposed with energy rays using methods such as immersion exposure. The coating / developing apparatus 2 coats the surface of the workpiece W (substrate) with the resist film before exposure processing by the exposure apparatus 3, and develops the resist film after exposure processing. By performing this series of processes, a resist film with a predetermined pattern is formed.

[0051] [Circuit board inspection equipment] The following describes the configuration of a coating and developing apparatus 2 as an example of a substrate processing apparatus. As shown in Figures 1 and 2, the coating and developing apparatus 2 comprises a carrier block 4, a processing block 5, an interface block 6, and a control device 100 (control unit). A display unit 200 is connected to the control device 100. The coating and developing apparatus 2 described in this embodiment as a substrate inspection apparatus has the function of inspecting the state of a target film formed on a substrate.

[0052] The carrier block 4 introduces the workpiece W into the coating / developing apparatus 2 and takes the workpiece W out of the coating / developing apparatus 2. For example, the carrier block 4 can support multiple carriers C (storage sections) for the workpiece W and incorporates a transport device A1 including a transfer arm. The carrier C accommodates, for example, multiple circular workpieces W. The transport device A1 takes the workpiece W from the carrier C and passes it to the processing block 5, and receives the workpiece W from the processing block 5 and returns it to the carrier C. The processing block 5 has multiple processing modules 11, 12, 13, and 14.

[0053] The processing module 11 incorporates a plurality of coating units U1, a plurality of heat treatment units U2, a plurality of imaging units U3, and a transport device A3 for transporting workpieces W to these units. The processing module 11 forms an underlayer film on the surface of the workpiece W using the coating units U1 and the heat treatment units U2. The coating unit U1 of the processing module 11 applies a processing liquid for underlayer film formation onto the workpiece W while rotating the workpiece W at a predetermined rotational speed. The heat treatment unit U2 of the processing module 11 performs various heat treatments associated with the formation of the underlayer film. The heat treatment unit U2 incorporates, for example, a hot plate and a cooling plate, and heats the workpiece W to a predetermined heating temperature using the hot plate, and then cools the heated workpiece W using the cooling plate to perform the heat treatment. The imaging unit U3 performs processing to inspect the surface condition of the workpiece W and acquires information indicating the surface condition of the workpiece W, such as information related to a surface image.

[0054] The processing module 12 incorporates multiple coating units U1, multiple heat treatment units U2, multiple imaging units U3, and a transport device A3 for transporting workpieces W to these units. The processing module 12 forms an intermediate film on the underlying film using the coating units U1 and the heat treatment units U2. The coating unit U1 of the processing module 12 forms a coating film on the surface of the workpiece W by applying a processing liquid for intermediate film formation onto the underlying film. The heat treatment unit U2 of the processing module 12 performs various heat treatments associated with the formation of the intermediate film. The heat treatment unit U2 incorporates, for example, a hot plate and a cooling plate, and heats the workpiece W to a predetermined heating temperature using the hot plate, and then cools the heated workpiece W using the cooling plate to perform the heat treatment. The imaging unit U3 performs processing to inspect the surface condition of the workpiece W and acquires information indicating the surface condition of the workpiece W, such as information related to a surface image.

[0055] The processing module 13 incorporates multiple coating units U1, multiple heat treatment units U2, multiple imaging units U3, and a transport device A3 for transporting workpieces W to these units. The processing module 13 forms a resist film on an interlayer using the coating units U1 and the heat treatment units U2. The coating unit U1 of the processing module 13 applies a processing liquid for resist film formation onto the interlayer while rotating the workpiece W at a predetermined rotational speed. The heat treatment unit U2 of the processing module 13 performs various heat treatments associated with the formation of the resist film. The heat treatment unit U2 of the processing module 13 forms a resist film by applying heat treatment (PAB: Post Applied Bake) to the workpiece W on which the coating film has been formed at a predetermined heating temperature. The imaging unit U3 performs processing to inspect the surface condition of the workpiece W and acquires information indicating the surface condition of the workpiece W, such as information related to a surface image.

[0056] The processing module 14 incorporates a plurality of coating units U1, a plurality of heat treatment units U2, and a transport device A3 for transporting workpieces W to these units. The processing module 14 performs development processing of the resist film R after exposure using the coating units U1 and the heat treatment units U2. For example, the coating unit U1 of the processing module 14 performs development processing of the resist film R by applying a developer solution to the surface of the exposed workpiece W while rotating the workpiece W at a predetermined rotation speed, and then washing it off with a rinsing solution. The heat treatment unit U2 of the processing module 14 performs various heat treatments associated with the development process. Specific examples of heat treatments include heat treatment before development (PEB: Post Exposure Bake) and heat treatment after development (PB: Post Bake).

[0057] A shelf unit U10 is provided on the carrier block 4 side within the processing block 5. The shelf unit U10 is divided into multiple cells arranged vertically. A transport device A7, including a lifting arm, is provided near the shelf unit U10. The transport device A7 raises and lowers the workpiece W between the cells of the shelf unit U10.

[0058] A shelf unit U11 is provided on the interface block 6 side within the processing block 5. The shelf unit U11 is divided into multiple cells arranged vertically.

[0059] The interface block 6 handles the transfer of workpieces W to and from the exposure device 3. For example, the interface block 6 incorporates a transport device A8, which includes a transfer arm, and is connected to the exposure device 3. The transport device A8 transfers the workpieces W placed on the shelf unit U11 to the exposure device 3, and receives the workpieces W from the exposure device 3 and returns them to the shelf unit U11.

[0060] [Imaging Unit] The imaging unit U3 included in processing modules 11 to 13 will now be described. The imaging unit U3 has the function of imaging the surface of a film (e.g., a base layer, an interlayer, a resist film, etc.) formed by the coating unit U1 and the heat treatment unit U2, and obtaining image data.

[0061] As shown in Figure 3, the imaging unit U3 includes a housing 30, a holding unit 31, a linear drive unit 32, an imaging unit 40, and a light-emitting / reflecting unit 50. The holding unit 31 holds the workpiece W horizontally. The linear drive unit 32 uses, for example, an electric motor as a power source to move the holding unit 31 along a horizontal, straight path (a path extending in the X-axis direction).

[0062] The configuration of the imaging unit 40 and the light-emitting / reflecting unit 50 will be explained with reference to Figure 4. Figure 4 is a schematic example of a part of the configuration of the imaging unit 40 and the light-emitting / reflecting unit 50 shown in Figure 3.

[0063] The imaging unit 40 has a camera 41. The camera 41 is located at one end of the imaging unit U3 in the direction of movement (X-axis direction) of the holding unit 31 and is directed toward the other end in that direction of movement. The camera 41 used is one that is sensitive to the visible light region with wavelengths from 380 nm to 780 nm and the infrared light region with wavelengths from 780 nm. In the infrared light region, a camera 41 that is particularly sensitive to the near-infrared light region with wavelengths from 780 nm to 1000 nm can be preferably used.

[0064] Specifically, such a camera 41 may be one that can separate the visible light region into three wavelength regions, as well as separate the visible light region from the near-infrared light region. A specific configuration of the camera 41 may be a 4-line color line scan camera in which four types of sensors (e.g., CMOS sensors) for RGB and near-infrared light (NIR) are arranged in a line. The R sensor, G sensor, and B sensor correspond to sensors that are sensitive to visible light (first imaging sensor), and the NIR sensor corresponds to a sensor that is sensitive to infrared light (near-infrared light) (second imaging sensor).

[0065] The four types of sensors may each be arranged to extend horizontally and in a direction perpendicular to the direction of movement of the holding part 31 (Y-axis direction).

[0066] The light-emitting and reflective unit 50 emits light into the imaging area and guides the reflected light from the imaging area towards the camera 41. For example, the light-emitting and reflective unit 50 is composed of a first light source unit 51, a second light source unit 52, an optical filter 53, and a half mirror 54.

[0067] The first light source unit 51 is a light source that emits visible light and has the function of emitting visible light toward the optical filter 53 below. The wavelength range of the visible light emitted from the first light source unit 51 is not particularly limited, but as an example, white light or similar light that evenly includes the wavelength range of visible light may be used. The second light source unit 52 has the function of emitting near-infrared light of a single wavelength as a type of infrared light. The second light source unit 52 is located at the same height as the optical filter 53 in the vertical direction and has the function of emitting near-infrared light toward the optical filter 53 along the direction of movement of the holding unit 31 (X-axis direction). The wavelength range of the near-infrared light emitted from the second light source unit 52 is not particularly limited, but as an example, light of a single wavelength of 850 nm may be used.

[0068] The first light source unit 51 and the second light source unit 52 are arranged within the housing 30 as elongated line light sources extending horizontally and in a direction perpendicular to the direction of movement of the holding unit 31 (Y-axis direction). The longitudinal lengths of the first light source unit 51 and the second light source unit 52 are greater than the diameter of the workpiece W.

[0069] The optical filter 53 is positioned higher than the half mirror 54 and has the function of guiding light from the first light source 51 and the second light source 52 toward the half mirror 54. The optical filter 53 corresponds to an incident direction adjustment unit that adjusts the direction of light incident on the workpiece W. The optical filter 53 is positioned inside the housing 30 at an angle of approximately 45° to the horizontal. The optical filter 53 is positioned above the middle portion of the holding unit 31 so as to be perpendicular to the direction of movement of the holding unit 31 (X-axis direction) when viewed from above. The optical filter 53 has a rectangular shape. The length of the optical filter 53 (length in the longitudinal direction) is greater than the diameter of the workpiece W.

[0070] Figure 5 shows a schematic diagram illustrating the optical characteristics of the optical filter 53. The optical filter 53 does not reflect light with wavelengths below 750 nm, which is the so-called visible light region, but transmits almost 100% of light with wavelengths above 750 nm, which is the so-called near-infrared light region. Therefore, as shown in Figure 4, by setting the inclination of the optical filter 53 so that the light emitted from the second light source 52 is reflected downwards, the light from the second light source 52 can be guided to the workpiece W. At this time, the positions of the first light source 51, the second light source 52, and the optical filter 53 are set so that the reflection position of the near-infrared light from the second light source 52 coincides with the optical axis of the light from the first light source 51. As a result, as shown in Figure 4, both visible light L1 and near-infrared light L2 reach the half mirror 54 via the same optical axis (intentionally shown slightly offset in Figure 4).

[0071] The half-mirror 54 is located below the optical filter 53 and above the holding part 31, and has the function of transmitting light from the optical filter 53 while reflecting light from below towards the camera 41. The half-mirror 54 corresponds to a direction changing part that changes the direction of the reflected light from the workpiece W.

[0072] The half-mirror 54 is positioned inside the housing 30 at an angle of approximately 45° to the horizontal. When viewed from above, the half-mirror 54 is positioned perpendicular to the direction of movement of the holding part 31 (X-axis direction) and overlaps with the optical filter 53. The half-mirror 54 has a rectangular shape. The length of the half-mirror 54 (length in the longitudinal direction) is greater than the diameter of the workpiece W.

[0073] The imaging unit U3 operates as follows to acquire image data of the surface of the workpiece W. First, the linear drive unit 32 moves the holding unit 31. This causes the workpiece W to pass under the half mirror 54. During this passage, the imaging unit 40 and the light projection / reflection unit 50 receive visible light L1 emitted downward from the first light source unit 51, which passes through the optical filter 53 and the half mirror 54 and is irradiated downward (towards the linear drive unit 32). Near-infrared light L2 emitted horizontally from the second light source unit 52 is reflected by the optical filter 53, changing its path downward, and passes through the half mirror 54 and is irradiated downward (towards the linear drive unit 32). As described above, if the light sources and optical filter 53 are set so that the optical axes of the light from the first light source unit 51 and the second light source unit 52 coincide, the light L1 and L2 will irradiate the same irradiation area.

[0074] The visible light L1 and near-infrared light L2 that pass through the half mirror 54 are reflected by the object (workpiece W) located below the half mirror 54. That is, the reflected light L3 may include reflected light L1' (first reflected light) for visible light L1 and reflected light L2' (second reflected light) for near-infrared light L1. The reflected light L3 is reflected again by the half mirror 54, passes through the lens of the camera 41, and enters the image sensor of the camera 41. That is, the camera 41 can image objects present in the illumination areas of the first light source unit 51 and the second light source unit 52 via the half mirror 54. For example, when the holding unit 31 that holds the workpiece W moves, the camera 41 can image the surface of the workpiece W as it passes through the illumination areas of the first light source unit 51 and the second light source unit 52. When the state of the film formed on the surface of the workpiece W changes (for example, film thickness, line width, defects, etc.), the image data of the workpiece W surface captured by the camera 41 changes, for example, the color of the workpiece W surface changes in accordance with the change in shape.

[0075] Image data acquired by camera 41 is sent to control device 100. The control device 100 can estimate the shape characteristic values ​​of the film on the surface of the workpiece W based on the image data, and the estimation results are stored as inspection results in the control device 100. The image data is also stored in the control device 100.

[0076] In the control device 100, normally one RGB image (color image) is formed based on the pixel information acquired by the R, G, and B sensors, and one NIR image (monochrome image) is formed based on the pixel information acquired by the NIR sensor. The R sensor, G sensor, B sensor, and NIR sensor are sensors that have sensitivity to different wavelength ranges. However, the configuration of the image output to the display unit 200 may be changed by the control of the control device 100. This point will be described later.

[0077] The display unit 200 connected to the control device 100 is, for example, a monitor. The monitor can be any type of device capable of displaying information on its screen, such as a liquid crystal panel. The display unit 200 may have a function to display the control content from the control device 100. The display unit 200 may also have a function to process and display the image captured by the imaging unit U3 based on user instructions, etc. This point will be discussed later.

[0078] [Control device] An example of the control device 100 will be described in detail. The control device 100 controls each element included in the coating and developing apparatus 2. The control device 100 is configured to perform process operations including forming the aforementioned films on the surface of the workpiece W and performing a developing process. The control device 100 is also configured to perform an inspection of the surface of the workpiece W and display the results. Here, an example of the configuration of the control device 100 as a substrate inspection device that performs substrate inspection in the coating and developing apparatus 2 will be described.

[0079] As shown in Figure 6, the control device 100 has the following functional configuration: an imaging instruction acquisition unit 101, an imaging control unit 102, an RGB image acquisition unit 103, an NIR image acquisition unit 104, an image holding unit 105, an inspection instruction acquisition unit 106, an image inspection unit 107, a display instruction acquisition unit 108, a channel setting change unit 109, and an image output unit 110.

[0080] The imaging instruction acquisition unit 101 has the function of acquiring instructions for imaging the workpiece W in the imaging unit U3. The instructions may be given, for example, by the user of the coating / developing apparatus 2. Alternatively, executing a pre-created program related to substrate processing of the workpiece W may substantially constitute an imaging instruction in the imaging unit U3.

[0081] The imaging control unit 102 has the function of controlling the imaging unit U3 to image the surface of the processed workpiece W based on the instructions acquired by the imaging instruction acquisition unit 101.

[0082] The RGB image acquisition unit 103 has the function of acquiring an RGB image of the surface of the workpiece W from the camera 41 of the imaging unit U3. Specifically, it acquires pixel information acquired by the three types of sensors of the camera 41: the R sensor, G sensor, and B sensor.

[0083] The NIR image acquisition unit 104 has the function of acquiring an NIR image of the surface of the workpiece W from the camera 41 of the imaging unit U3. Specifically, it acquires pixel information acquired by the NIR sensor of the camera 41.

[0084] The image holding unit 105 has the function of holding images acquired by the RGB image acquisition unit 103 and the NIR image acquisition unit 104. The image information held by the image holding unit 105 is used in the inspection of the workpiece W. It can also be used for display on the display unit 200 based on user instructions, etc.

[0085] The inspection instruction acquisition unit 106 has the function of acquiring instructions related to the inspection of the workpiece W based on the image of the workpiece W captured by the imaging unit U3. The instructions may be given, for example, by the user of the coating and developing apparatus 2. Alternatively, executing a pre-created program related to substrate processing of the workpiece W may constitute an instruction related to the actual inspection.

[0086] The image inspection unit 107 has the function of controlling the inspection of the workpiece W using an image of the workpiece W, based on the instructions acquired by the inspection instruction acquisition unit 106. The inspection of the workpiece W using an image is an inspection for the presence or absence of defects in the workpiece W. As mentioned above, if there is a defect in the film formed on the workpiece W, the captured image may change. Also, the information contained in the image may differ between a visible light image (RGB image) and a near-infrared light image (NIR image). Therefore, the image inspection unit 107 uses the above-mentioned visible light image and near-infrared light image to inspect the presence or absence of defects in the workpiece W in detail.

[0087] One example of an image-based inspection method for defects in a workpiece W is an inspection method that compares a visible light image with a near-infrared image. Visible light images generally allow for a detailed understanding of changes on the surface of the workpiece W. On the other hand, since near-infrared light can be reflected from the inner surface of the workpiece W, the near-infrared image shows information about the inner layers of the workpiece W rather than the surface. Therefore, by observing the near-infrared image, it is possible to discover defects in parts of the workpiece W that were not previously detectable, such as those on the surface. Similarly, by comparing a visible light image with a near-infrared image, it becomes possible to identify, for example, that color unevenness, which is only present in the visible light image, originates from defects in the surface layer.

[0088] The display instruction acquisition unit 108 has the function of acquiring instructions related to the display of an image on the display unit 200. The instructions may be given, for example, by the user of the coating / developing apparatus 2. Alternatively, the system may be configured to acquire instructions to change the display content as part of the inspection instructions.

[0089] The channel setting change unit 109 has the function of setting the channel connected to the display unit 200 in order to output an image on the display unit 200 based on the instructions from the display instruction acquisition unit 108.

[0090] The channel setting change in the channel setting change unit 109 will be explained with reference to Figure 7. Figure 7(a) explains how the visible light image (RGB image) acquired by the RGB image acquisition unit 103 and the near-infrared light image (NIR image) acquired by the NIR image acquisition unit 104 are configured.

[0091] As described above, an RGB image is a color image created by combining pixel information from three types of sensors (R sensor, G sensor, and B sensor). When displaying an image in the display unit 200, the pixel information from each sensor is assigned to one channel (ch), and these are combined to output an image. In other words, when the display unit 200 outputs an RGB image, it is output by superimposing three channels of images. To put it another way, an RGB image can be decomposed into three color images: the R image from the R sensor, the G image from the G sensor, and the B image from the B sensor.

[0092] On the other hand, since an NIR image is a planar representation of pixel information from a single type of sensor (NIR sensor), it cannot be decomposed like the RGB image described above. Therefore, when displaying it on the display unit 200, it is sufficient to assign the pixel information of the NIR sensor to a single channel.

[0093] Thus, the camera 41 acquires pixel information from four types of sensors. On the other hand, when displaying an image on the display unit 200, it is possible to combine images from channels 1 to 3. Therefore, by changing the type of image assigned to channel 3, it is possible to generate and display a pseudo-RGB image, which is a composite image different from a normal RGB image.

[0094] Figure 7(b) shows examples of image type combinations to assign to each channel when generating images to be displayed on the display unit 200 using three channels (1ch to 3ch). Figure 7(b) shows all possible combinations when assigning one of the four types of images captured by the sensors (R image, G image, B image, NIR image) to all three channels (1ch to 3ch). By changing the type of image assigned to each channel in this way, different images (output images 1 to 4) can be displayed on the display unit 200. The channel setting change unit 109 has the function of determining which sensor's captured image is assigned to the three channels on the display unit 200.

[0095] The image output unit 110 has the function of selecting image information to be displayed in the display unit 200 from the information held in the image holding unit 105 based on the settings in the channel setting change unit 109, and outputting the image to each channel of the display unit 200. As a result, the display unit 200 can combine the images assigned to the three channels and display a single pseudo-RGB image.

[0096] By creating such a pseudo-RGB image and displaying it on the display unit 200, users may be able to obtain information that they could not perceive in a normal RGB image or NIR image. For example, when inspecting defects in the film of a specific workpiece W, it may be difficult to detect defects in images related to a specific wavelength range, for example, due to the color of the workpiece W. In such cases, by excluding the image related to the wavelength range in which defects are difficult to detect and combining the remaining three images to display a pseudo-RGB image on the display unit 200, it may be possible to make it easier for users to visually confirm whether or not there are defects in the workpiece W.

[0097] Furthermore, the above-mentioned pseudo-RGB image may be used when inspecting workpiece W. That is, in addition to comparing the visible light image and the near-infrared light image, the inspection for defects in workpiece W may also be performed by comparing, for example, the pseudo-RGB image with the visible light image, or the pseudo-RGB image with the near-infrared light image.

[0098] The control device 100 is composed of one or more control computers. For example, the control device 100 has the circuit 120 shown in Figure 8. The circuit 120 has one or more processors 121, a memory 122, a storage 123, and an input / output port 124. The storage 123 has a storage medium that can be read by the computer, such as a hard disk. The storage medium stores a program that causes the control device 100 to execute the board inspection procedure described later. The storage medium may be a removable medium such as a non-volatile semiconductor memory, magnetic disk, or optical disk. The memory 122 temporarily stores the program loaded from the storage medium of the storage 123 and the calculation results by the processor 121. The processor 121 executes the above program in cooperation with the memory 122 to constitute each of the above-described functional modules. The input / output port 124 inputs and outputs electrical signals to and from the controlled component according to commands from the processor 121.

[0099] Furthermore, the hardware configuration of the control device 100 is not necessarily limited to a configuration in which each functional module is composed by a program. For example, each functional module of the control device 100 may be composed of a dedicated logic circuit or an ASIC (Application Specific Integrated Circuit) that integrates such circuits.

[0100] In the following embodiments, the above configuration is described in the case where it is included in the control device 100, but the control device 100 does not necessarily have to include all of the above functions. For example, a configuration in which a database function such as the image holding unit 105 is provided in an external device is also possible.

[0101] Furthermore, the control device 100 and the display unit 200 may be connected to the carrier block 4, processing block 5, and interface block 6 of the coating / developing apparatus 2 by a wired or wireless network. In other words, the control device 100 may be located at a position separated from the block that actually processes the workpiece W in the coating / developing apparatus 2.

[0102] [Processing Procedure] The process procedures performed in the coating and developing apparatus 2 will be described below.

[0103] In the process processing procedure, first the control device 100 controls the transport device A1 to transport the workpiece W to be processed in the carrier C to the shelf unit U10, and then controls the transport device A7 to place the workpiece W into a cell for the processing module 11.

[0104] Next, the control device 100 controls the transport device A3 to transport the workpiece W from the shelf unit U10 to the coating unit U1 and the heat treatment unit U2 in the processing module 11. The control device 100 also controls the coating unit U1 and the heat treatment unit U2 to form an underlayer film on the surface of the workpiece W. After that, the control device 100 controls the transport device A3 to return the workpiece W with the underlayer film formed on it back to the shelf unit U10, and controls the transport device A7 to place the workpiece W into a cell for the processing module 12.

[0105] Next, the control device 100 controls the transport device A3 to transport the workpiece W from the shelf unit U10 to the coating unit U1 and the heat treatment unit U2 in the processing module 12. The control device 100 also controls the coating unit U1 and the heat treatment unit U2 to form an intermediate film on the underlying film of the workpiece W. For example, the control device 100 controls the coating unit U1 to form an intermediate film by applying a processing liquid for intermediate film formation to the underlying film of the workpiece W. Next, the control device 100 controls the heat treatment unit U2 to apply heat treatment to the intermediate film. After the intermediate film is formed, the control device 100 controls the transport device A3 to transport the workpiece W to the imaging unit U3, and controls the imaging unit U3 to image the surface of the workpiece W and acquire image information (underlying image). After that, the control device 100 controls the transport device A3 to return the workpiece W to the shelf unit U10, and controls the transport device A7 to place the workpiece W in a cell for the processing module 13.

[0106] Next, the control device 100 controls the transport device A3 to transport the workpiece W from the shelf unit U10 to each unit in the processing module 13, and controls the coating unit U1 and the heat treatment unit U2 to form a resist film on the interlayer of the workpiece W. For example, the control device 100 controls the coating unit U1 to form a resist film by applying a processing liquid for resist film formation to the interlayer of the workpiece W. Next, the control device 100 controls the heat treatment unit U2 to apply heat treatment to the resist film. After the resist film is formed, the control device 100 controls the transport device A3 to transport the workpiece W to the imaging unit U3, and controls the imaging unit U3 to image the surface of the workpiece W and acquire image information (processed image). After that, the control device 100 controls the transport device A3 to transport the workpiece W to the shelf unit U11.

[0107] Next, the control device 100 controls the transport device A8 to send the workpiece W from the shelf unit U11 to the exposure device 3. Subsequently, the control device 100 controls the transport device A8 to receive the exposed workpiece W from the exposure device 3 and place it in the cell for the processing module 14 in the shelf unit U11.

[0108] Next, the control device 100 controls the transport device A3 to transport the workpiece W from the shelf unit U11 to each unit in the processing module 14, and controls the coating unit U1 and the heat treatment unit U2 to perform a developing process on the resist film R of the workpiece W. After that, the control device 100 controls the transport device A3 to return the workpiece W to the shelf unit U10, and controls the transport devices A7 and A1 to return the workpiece W to the carrier C. This completes the process.

[0109] [Circuit board inspection method] Referring to Figure 9, the substrate inspection method controlled by the control device 100 of the coating and developing apparatus 2 will be explained.

[0110] First, the control device 100 executes step S01. In step S01, the imaging instruction acquisition unit 101 acquires an imaging instruction, and the inspection instruction acquisition unit 106 acquires an inspection instruction. Here, it is assumed that the control device 100 acquires a series of instructions related to substrate processing, including the inspection of the workpiece W. In this case, the control device 100 may acquire both an imaging instruction and an inspection instruction.

[0111] Next, the control device 100 executes step S02. In step S02, the imaging control unit 102 controls the imaging unit U3 to perform imaging with the camera 41. The resulting visible light image (RGB image) and near-infrared light image (NIR image) are acquired by the RGB image acquisition unit 103 and the NIR image acquisition unit 104, respectively, and held in the image holding unit 105.

[0112] Next, the control device 100 executes step S03. In step S03, the image inspection unit 107 inspects the surface of the workpiece W for defects using the visible light image and near-infrared light image held by the image holding unit 105. At this time, the pseudo-RGB image described above may also be used for inspection.

[0113] Next, the control device 100 executes step S04. In step S04, the image inspection unit 107 outputs the inspection results. One example of an output destination is the display unit 200, but the configuration may also be such that the inspection results are output to an external device other than the display unit 200.

[0114] Next, the control device 100 executes step S05. In step S05, the channel setting change unit 109 assigns images to the channels of the display unit 200 based on the image display instructions for the display unit 200 acquired by the display instruction acquisition unit 108.

[0115] Next, the control device 100 executes step S06. In step S06, the image output unit 110 outputs an image to the display unit 200 based on the settings made by the channel setting change unit 109.

[0116] In Figure 9, the series of processes are explained sequentially as S01 to S09, but steps S01 to S04 and steps S05 and S06 may be performed independently. Also, the timing of steps S01 and S02 and the timing of steps S03 and S04 may be performed independently of each other. Furthermore, the acquisition of the inspection instruction described in step S01 may be acquired at a different timing than step S01, and this acquisition of the inspection instruction may be used as a trigger for executing step S03. Thus, the procedure of the process shown in Figure 9 can be modified as appropriate.

[0117] [Effect] In the coating / developing apparatus 2 and substrate inspection method corresponding to the substrate inspection apparatus described above, a visible light image of the substrate surface is acquired by a first imaging sensor (RGB sensor), and an infrared image of the substrate surface is acquired by a second imaging sensor (NIR sensor). Therefore, the substrate can be inspected using these two types of images. The visible light image and the infrared light image contain different information for detecting defects in the substrate, and using these images for inspection allows for obtaining more detailed information about the substrate. Therefore, with the above configuration, it becomes possible to acquire images that can detect defects in the substrate with higher accuracy.

[0118] In particular, infrared imaging can be effective when the controlled treatment film on the substrate is thick (around a few micrometers). With visible light imaging, especially when the thickness of the treatment film is large, it becomes difficult to detect defects other than surface irregularities, making it difficult to detect defects that are not easily discernible as surface irregularities, such as striations, film unevenness, and comets. On the other hand, infrared imaging can detect changes in the film other than surface irregularities. Therefore, by combining visible light imaging and infrared imaging, it is possible to obtain information on a wider variety of defects, making it possible to detect defects that could not be detected with visible light imaging alone.

[0119] Here, a half-mirror 54 may be further provided as a direction-changing unit that changes the direction of the first reflected light L1' and the second reflected light L2' (i.e., reflected light L3) to the same direction. Alternatively, the first image sensor may receive the first reflected light L1' whose direction has been changed by the half-mirror 54, and the second image sensor may receive the second reflected light L2' whose direction has also been changed by the half-mirror 54. With the above configuration, the arrangement of the first image sensor and the second image sensor can be changed more flexibly compared to the case without a direction-changing unit.

[0120] The first and second imaging sensors may be housed in the same camera 41. With this configuration, visible light images and infrared light images can be acquired with a single camera, thus preventing the substrate inspection device from becoming larger.

[0121] The system may further include an optical filter 53 as an incidence direction adjustment unit that adjusts the visible light L1 from the first light source and the near-infrared light L2 (infrared light) from the second light source to be incident in the same direction to the substrate. With this configuration, the arrangement of the first and second light sources can be changed more flexibly compared to the case without an incidence direction adjustment unit.

[0122] The visible light L1 incident on the substrate, the near-infrared light L2 incident on the substrate, the first reflected light L1' emitted from the substrate, and the second reflected light L2' emitted from the substrate may lie on the same optical axis. By adopting such a configuration, the space in which the optical axes of these lights exist can be reduced. Therefore, it is possible to reduce restrictions on the device configuration, such as configuring the device so as not to obstruct the path of light, and thus the arrangement of components other than the optical system can be flexibly changed.

[0123] The holding unit, first light source unit, second light source unit, first imaging sensor, and second imaging sensor may be housed in a single imaging unit U3. Alternatively, the control device 100, acting as the control unit, may control the imaging unit U3 to perform visible light image acquisition and infrared light image acquisition. Furthermore, the control unit may perform control for inspection of the substrate using the visible light image and infrared light image. With the above configuration, the control unit can comprehensively control the acquisition of visible light image and infrared light image, and the inspection of the substrate using these images.

[0124] The holding unit 31 may be movable horizontally within the imaging unit U3. Furthermore, under control by the control unit, visible light image acquisition and infrared light image acquisition may be performed in parallel while the holding unit 31 is moving. With this configuration, the time required for acquiring visible light and infrared light images can be shortened, thereby reducing the time required for substrate inspection.

[0125] Furthermore, the control unit may detect defects on the substrate surface by comparing the visible light image and the infrared light image. The information relating to substrate defects contained in the visible light image and the information relating to substrate defects contained in the infrared light image are not identical and may contain different information from each other. Therefore, by configuring the system to detect defects by comparing the two images, it becomes possible to detect defects that cannot be detected by one image alone.

[0126] Furthermore, the visible light image is an image formed by combining multiple color component images of different types, and the control unit may display on the display unit an image formed by combining the infrared light image with at least one of the aforementioned color component images. For example, as described in the above embodiment, it may be displayed on the display unit 200 as a pseudo-RGB image. With this configuration, a composite image different from a normal visible light image or infrared light image is displayed on the display unit, so the user can see an image of a different type than a visible light image or infrared light image.

[0127] [Differentiation] Although various exemplary embodiments have been described above, the invention is not limited to the exemplary embodiments described above, and various omissions, substitutions, and modifications may be made. Furthermore, it is possible to combine elements from different embodiments to form other embodiments.

[0128] For example, in the above embodiment, a near-infrared image was described as an infrared image, but the method is not limited to the near-infrared wavelength range of approximately 780 mm to 2 μm, and a configuration using infrared light with a wavelength greater than 2 μm may also be used.

[0129] Furthermore, although the above embodiment describes a case in which both a visible light image and a near-infrared light image are simultaneously captured in a single imaging unit U3 while moving the workpiece W, instead of this configuration, the visible light image and the near-infrared light image may be captured sequentially. Also, the arrangement of the light source and camera within the imaging unit U3 can be changed as appropriate. In addition, the number and arrangement of optical elements for adjusting the path of light, such as the optical filter 53 and half mirror 54, may be changed as appropriate depending on the arrangement of the light source and camera.

[0130] From the above description, it will be understood that the various embodiments of this disclosure are described herein for illustrative purposes and can be modified in various ways without departing from the scope and spirit of this disclosure. Accordingly, the various embodiments disclosed herein are not intended to limit the scope and spirit, and the true scope and spirit are shown by the appended claims. [Explanation of Symbols]

[0131] 1...Substrate processing system, 2...Coating / developing device, 3...Exposure device, 30...Housing, 31...Holding unit, 32...Linear drive unit, 40...Imaging unit, 41...Camera, 50...Reflection unit, 51...First light source unit, 52...Second light source unit, 53...Optical filter, 54...Half mirror, 100...Control device (control unit), 101...Imaging instruction acquisition unit, 102...Imaging control unit, 103...RGB image acquisition unit, 104...NIR image acquisition unit, 105...Image holding unit, 106...Inspection instruction acquisition unit, 107...Image inspection unit, 108...Display instruction acquisition unit, 109...Channel setting change unit.

Claims

1. A substrate inspection apparatus that inspects a substrate using an image of the substrate's surface, A holding portion for holding the substrate, A first light source unit that emits visible light to the substrate held in the holding unit, A second light source unit emits infrared light to the substrate held in the holding unit, A first imaging sensor that receives first reflected light emitted from the substrate by irradiating it with visible light and captures a visible light image of the surface of the substrate, A second imaging sensor receives a second reflected light emitted from the substrate by irradiating it with the aforementioned infrared light and captures an infrared light image of the surface of the substrate. A control unit controls the holding unit, the first light source unit, the second light source unit, the first image sensor, and the imaging unit housing the second image sensor to capture the visible light image with the first image sensor and the infrared light image with the second image sensor, and to detect defects on the surface of the substrate by comparing the visible light image and the infrared light image. It has, The second imaging sensor is a substrate inspection device that is sensitive to light with a wavelength of at least 780 to 1000 nm.

2. The device further includes a direction-changing unit that changes the direction of the first reflected light and the second reflected light to the same direction. The first imaging sensor receives the first reflected light whose direction has been changed by the direction changing unit, The substrate inspection apparatus according to claim 1, wherein the second imaging sensor receives the second reflected light whose direction has been changed by the direction changing unit.

3. The substrate inspection apparatus according to claim 1 or 2, wherein the first imaging sensor and the second imaging sensor are housed in the same camera.

4. A substrate inspection apparatus according to any one of claims 1 to 3, further comprising an incidence direction adjustment unit for adjusting the visible light from the first light source and the infrared light from the second light source to be incident in the same direction with respect to the substrate.

5. A substrate inspection apparatus according to any one of claims 1 to 4, wherein the visible light incident on the substrate, the infrared light incident on the substrate, the first reflected light emitted from the substrate, and the second reflected light emitted from the substrate are on the same optical axis.

6. The holding portion is movable horizontally within the imaging unit, Controlled by the control unit, The substrate inspection apparatus according to any one of claims 1 to 5, wherein while the holding portion is moving, the imaging of the visible light image by the first imaging sensor and the imaging of the infrared light image by the second imaging sensor are performed in parallel.

7. The visible light image is an image obtained by combining multiple color component images that have different color components from each other, The substrate inspection apparatus according to any one of claims 1 to 6, wherein the control unit causes the display unit to display an image obtained by combining the infrared light image and at least one of the multiple types of color component images.

8. A substrate inspection method for inspecting a substrate using an image of the substrate's surface, The substrate is held by the holding part, The first light source emits visible light to the substrate held in the holding portion, The second light source emits infrared light to the substrate held in the holding part, The first reflected light emitted from the substrate by irradiating it with visible light is received by the first imaging sensor to capture a visible light image of the surface of the substrate. The infrared light is irradiated onto the substrate, and the second reflected light emitted from the substrate is received by a second imaging sensor that is sensitive to light with a wavelength of at least 780 to 1000 nm, thereby capturing an infrared light image of the surface of the substrate. The control unit acquires the visible light image and the infrared light image, and by comparing the visible light image and the infrared light image, it detects defects on the surface of the substrate. A circuit board inspection method, including the following.

9. The direction changing unit further includes changing the direction of the first reflected light and the second reflected light to the same direction, In capturing the visible light image, the first imaging sensor receives the first reflected light whose direction has been changed by the direction changing unit. The substrate inspection method according to claim 8, wherein, in capturing the infrared light image, the second imaging sensor receives the second reflected light whose direction has been changed by the direction changing unit.

10. The substrate inspection method according to claim 8 or 9, wherein the first imaging sensor and the second imaging sensor are housed in the same camera.

11. A substrate inspection method according to any one of claims 8 to 10, further comprising adjusting the visible light from the first light source and the infrared light from the second light source with an incidence direction adjustment unit so that they are incident on the substrate in the same direction.

12. The substrate inspection method according to any one of claims 8 to 11, wherein the visible light incident on the substrate, the infrared light incident on the substrate, the first reflected light emitted from the substrate, and the second reflected light emitted from the substrate are on the same optical axis.

13. The holding part is movable in the horizontal direction, A substrate inspection method according to any one of claims 8 to 12, wherein, under control by the control unit, while the holding unit is moving, the imaging of the visible light image by the first imaging sensor and the imaging of the infrared light image by the second imaging sensor are performed in parallel.

14. The visible light image is an image obtained by combining multiple color component images that have different color components from each other, The substrate inspection method according to any one of claims 8 to 13, further comprising the control unit displaying on a display unit an image obtained by synthesizing the infrared light image and at least one of the multiple types of color component images.

15. A circuit board inspection program for a circuit board inspection apparatus, which causes a computer to perform an inspection of the circuit board using an image of the surface of the circuit board, The substrate is held by the holding part, The first light source emits visible light to the substrate held in the holding portion, The second light source emits infrared light to the substrate held in the holding part, The first reflected light emitted from the substrate by irradiating it with visible light is received by the first imaging sensor to capture a visible light image of the surface of the substrate. The infrared light is irradiated onto the substrate, and the second reflected light emitted from the substrate is received by a second imaging sensor that is sensitive to light with a wavelength of at least 780 to 1000 nm, thereby capturing an infrared light image of the surface of the substrate. The control unit acquires the visible light image and the infrared light image, and by comparing the visible light image and the infrared light image, it detects defects on the surface of the substrate. A circuit board inspection program that causes the aforementioned computer to execute.

Images