WO2015174114A1

WO2015174114A1 - Substrate inspection device

Info

Publication number: WO2015174114A1
Application number: PCT/JP2015/054909
Authority: WO
Inventors: 洋行上田; 善洋橘; 彰秀今村; 年弘木村
Original assignee: 東レエンジニアリング株式会社
Priority date: 2014-05-16
Filing date: 2015-02-23
Publication date: 2015-11-19
Also published as: JP2015219085A; TW201546443A

Abstract

Provided is an optical inspection device capable of separating a front and back side of a substrate under inspection and maintaining inspection accuracy even if the substrate becomes thin. More specifically, a substrate inspection device provided with a substrate holding part, illumination unit, imaging unit, and inspection unit, wherein: the illumination unit is disposed so as to irradiate illumination light at a prescribed angle with respect to a first surface of a substrate; the imaging unit is provided with a substrate first surface imaging unit for observing, from the side of the first surface, a first-surface-side area under inspection set on the first surface side of the substrate and a substrate second surface imaging unit for observing, from the side of the first surface, a second-surface-side area under inspection set on a second surface side that faces and is opposite from the first surface of the substrate; the first surface imaging unit is disposed so as to image the first-surface-side area under inspection at a prescribed angle with respect to the first surface of the substrate; and the second surface imaging unit is disposed so as to image the second-surface-side area under inspection at a prescribed angle with respect to the second surface of the substrate.

Description

Board inspection equipment

The present invention relates to an apparatus for optically inspecting for the presence or absence of defects such as foreign matter and scratches attached to the front or back side of a transparent body such as a glass substrate.

In the conventional surface defect inspection of the liquid crystal panel, the detection optical system is symmetrically arranged on each of the front side and the back side, and the front side defect and the back side defect are separately inspected. (For example, patent document 1).

In addition, the illumination light is irradiated to the inspection target substrate from the oblique direction, and an imaging optical system having a focal depth smaller than the thickness of the inspection target substrate is disposed at a light receiving angle of 90 degrees with respect to the substrate surface, A technique capable of inspecting at a time without confusing the front side and the back side of the substrate to be inspected has been put into practical use (for example, Patent Document 2).

FIG. 4 is an external view showing an example of a conventional substrate inspection apparatus. The conventional substrate inspection apparatus 1z irradiates the illumination light 32 from the illumination unit 3 toward the inspection target region Rz of the substrate Wz to be inspected, and the scattered light emitted from the inspection target region Rz is located above the substrate Wz. An image is captured using the imaging camera 42z of the observation unit 4z provided, and an inspection is performed based on the captured image. The substrate Wz is held on the substrate mounting table 20, and the substrate mounting table 20 is mounted on the X-axis stage 61 and the Y-axis stage 62 mounted on the apparatus frame 11z. It can move in a direction at a predetermined speed and stop at a predetermined position. In addition, the imaging camera 42z has the apparatus frame 11z via the connecting member 15z so that the normal line of the inspection target region Rz of the substrate Wz coincides with the optical axis direction (that is, in the direction perpendicular to the surface of the substrate Wz). Is attached. For this reason, the entire substrate Wz is divided and scanned multiple times while the substrate Wz and the imaging unit 4z are opposed to each other for imaging and inspection.

Japanese Patent Laid-Open No. 3-189491 Japanese Patent No. 4104924

If you want to quickly inspect for defects such as foreign matter and scratches attached to the front and back sides of the substrate to be inspected, two sets of optical systems for inspection are arranged on the front and back sides as shown in Patent Document 1. In such a device configuration, the cost and size of the inspection device itself are increased.

On the other hand, as shown in Patent Document 2, even if a single inspection optical system is used and a device that can inspect the front side and the back side of the inspection target substrate separately is used, the substrate becomes thinner as the inspection target substrate becomes thinner. It becomes difficult to separate the front surface side and the back surface side (that is, front / back separation).

FIG. 5 is a conceptual diagram showing a state in which the front and back surfaces of a substrate are inspected using a conventional substrate inspection apparatus, and the scattered light irregularly reflected by a foreign substance attached to the substrate by irradiating illumination light onto the substrate to be inspected. A state in which an image is captured and the intensity of the captured scattered light are illustrated in a composite manner. FIG. 5A shows a state in which a substrate Wz (thickness: tz) that has been conventionally inspected is inspected, and FIG. 5B shows a substrate W (thickness: t) that is thinner than the conventional one. ) Is shown. The illumination light 32z emitted from the illumination unit is irregularly reflected on the surface of the foreign matter X1 attached to the front side of the substrates Wz and W and the surface of the foreign matter X2 attached to the back side of the substrates Wz and W, and the scattered light is imaged. The image is captured by the imaging camera 42z of the unit 4z.

In the case of the conventional substrate Wz, the scattered light intensities of the foreign matter X1 on the front surface side and the foreign matter X2 on the back surface side do not interfere with each other, and thus can be detected in a separated state. However, in the case of the substrate W thinner than the conventional one, since the scattered light intensities of the foreign matter X1 on the front surface side and the foreign matter X2 on the back surface side interfere with each other, it is difficult to separate the front and back and maintain the inspection accuracy.

Therefore, an object of the present invention is to provide an optical inspection apparatus capable of maintaining inspection accuracy by separating the front and back sides even when the inspection target substrate becomes thin.

In order to solve the above problems, an aspect of the present invention is as follows.
A substrate holding unit, an illumination unit, an imaging unit, and an inspection unit;
The illumination unit is arranged to irradiate light sheet-shaped illumination light at a predetermined angle with respect to the first surface of the substrate,
The imaging unit
A first surface side inspection object region set on the first surface side of the substrate or a second surface side inspection object region set on the second surface side opposite to the first surface of the substrate; An imaging unit that images from the first surface side of the substrate,
The imaging unit is a substrate inspection apparatus arranged at a predetermined angle with respect to a normal line of the first surface of the substrate.

According to this configuration, if the image is acquired by imaging the front surface side of the substrate, a predetermined inspection can be performed without being affected by the state of the back surface side of the substrate. Or if it is the image acquired by imaging the back surface side of a board | substrate, a predetermined test | inspection can be performed without being influenced by the state of the surface side of a board | substrate.

Another aspect of the present invention is as follows.
A substrate holding unit, an illumination unit, an imaging unit, and an inspection unit;
The illumination unit is arranged to irradiate light sheet-shaped illumination light at a predetermined angle with respect to the first surface of the substrate,
The imaging unit
A substrate first surface side imaging unit for observing a first surface side inspection target region set on the first surface side of the substrate from the first surface side;
A substrate second surface side imaging unit configured to image from the first surface side a second surface side inspection target region set on the second surface side opposite to the first surface of the substrate;
The substrate first surface imaging unit and the substrate second surface imaging unit are arranged so as to image the first surface side inspection target region at a predetermined angle with respect to a normal line of the first surface of the substrate. It is a substrate inspection apparatus.

According to this configuration, the front side and the back side of the substrate can be separately imaged separately, and the image acquired by imaging the front side of the substrate is not affected by the state of the back side of the substrate, and a predetermined inspection is performed. It can be carried out. On the other hand, an image acquired by imaging the back surface side of the substrate is not affected by the state of the front surface side of the substrate, and a predetermined inspection can be performed.

¡Even when the inspection target substrate becomes thinner, the inspection accuracy can be maintained by separating the front and back.

The external view which shows an example of the form which embodies this invention. The conceptual diagram which shows a mode that the front and back of a board | substrate thinner than before is inspected using the board | substrate inspection apparatus which embodies this invention. Sectional drawing which shows the variation of the board | substrate holding part which comprises this invention. The external view which shows an example of the conventional board | substrate inspection apparatus. The conceptual diagram which shows a mode that the front and back of a board | substrate is test | inspected using the conventional board | substrate inspection apparatus.

DESCRIPTION OF EMBODIMENTS Embodiments for carrying out the present invention will be described with reference to the drawings.
FIG. 1 is an external view showing an example of a form embodying the present invention.
FIG. 1 is a composite view of a perspective view of each component device and a block diagram of a configuration necessary for acquiring and inspecting an image of a substrate inspection apparatus 1 that performs an optical inspection based on an image obtained by imaging a substrate. Has been. In each figure, the three axes of the orthogonal coordinate system are X, Y, and Z, the XY plane is the horizontal plane, and the Z direction is the vertical direction. In particular, in the Z direction, the direction of the arrow is represented as the top, and the opposite direction is represented as the bottom. Further, the substrate W to be inspected has a first surface S1 and a second surface S2 facing the first surface, and the first surface S1 side is referred to as the first surface side or the surface side and is opposed thereto. The second surface S2 side is referred to as the second surface side or the back surface side.

A substrate inspection apparatus 1 according to an example of a form embodying the present invention includes a substrate holding unit 2, an illumination unit 3, an imaging unit 4, and an inspection unit 5. Furthermore, the board inspection apparatus 1 may be configured to include the relative movement unit 6 as necessary.

The substrate holding unit 2 holds the substrate W to be inspected.
Specifically, the substrate holding unit 2 can be configured by the substrate mounting table 20. The substrate mounting table 20 has a cross-sectional shape in which the inside is slightly hollow or recessed from the outer dimension of the substrate W. The substrate mounting table 20 is provided with positioning reference pins 21 slightly outside the outer dimensions of the substrate W. Alternatively, the configuration shown in FIG.

The illuminating unit 3 irradiates illumination light toward the inspection target region set on the substrate W. Further, the illumination unit 3 is arranged to irradiate the illumination light at a predetermined angle with respect to the normal line H1 of the first surface S1 of the substrate W. That is, for the first surface S1 of the substrate W,
Illumination light is irradiated from an oblique direction.

Specifically, the illumination unit 4 can be exemplified by a semiconductor laser, an LED, a lamp light source, or the like, and illumination light is irradiated toward the inspection target region through a lens, a mirror, or the like. More specifically, in the case of using a semiconductor laser, a configuration in which light is irradiated as light sheet-like illumination light through a cylindrical lens or the like can be exemplified. Further, as shown in FIG. 1, the illumination light emitted from the illuminating unit 4 may be directly applied to the inspection target region, or may be applied to the inspection target region after being reflected by a reflection mirror or the like.

The imaging unit 4 images the inspection target area. And the imaging part 4 is the 1st surface side inspection object area | region set to the 1st surface S1 side of the board | substrate W, or the 2nd surface side inspection object area | region set to the 2nd surface S2 side of the board | substrate W, It is observed from the first surface S1 side. The substrate first surface imaging unit 4 is arranged to image the first surface-side inspection target region V1 at a predetermined angle θ1 with respect to the first surface S1 of the substrate. That is, the inspection target region is imaged from the oblique direction with respect to the first surface S1 of the substrate W.

Specifically, the imaging unit 4 includes an imaging camera 42 and a lens 43. More specifically, the imaging camera 42 can be exemplified by an imaging device 44 that includes an area sensor such as a CCD or CMOS, a line sensor, or a TDI sensor. The imaging camera 42 can output a video signal and image data corresponding to the image received by the imaging device 44 to the outside. FIG. 1 shows a configuration including a line sensor as the image sensor 49.

Note that the imaging unit 4 is configured to perform imaging while focusing on either the first surface S1 of the substrate W or the second surface of the substrate W.

For example, the imaging unit 4 is configured to be attached to the apparatus frame 11 with the distance from the substrate W being fixed. By doing so, the imaging unit 4 can inspect either the first surface S1 of the substrate W or the second surface of the substrate W.

Alternatively, the imaging unit 4 may be configured to be attached to the device frame 15 via a mechanism (for example, a camera position changing unit) that changes the imaging position. In this case, the camera position changing unit shifts and shifts the optical path difference calculated from the thickness of the substrate W, the refractive index of the substrate W, and the predetermined angle θ1 where the imaging camera 42 is mounted obliquely with respect to the normal line H1. It is set as the structure which can be performed. The direction of this shift movement is the thickness of the substrate W, the refractive index of the substrate W, the predetermined angle θ1 at which the imaging camera 42 is mounted obliquely with respect to the normal H1, and the working distance of the lens 43 of the imaging unit 4 Calculated by (so-called working distance).

As a specific configuration of the camera position changing unit, a manual actuator including a guide rail extending in the shift movement direction, a ball screw, and a handwheel handle, or an electric motor including a rotation motor instead of the handwheel handle is provided. An actuator etc. can be illustrated. The actuator described above is not only a mechanism that moves only in the shift movement direction (that is, the uniaxial direction), but also in a direction (X direction) parallel to the surface of the substrate W and a thickness direction (the Z direction) (that is, It may be a mechanism that moves in two axial directions.

Since the imaging unit 4 is attached via the camera position changing unit having such a configuration, the first surface S1 or the second surface S2 of the substrate W is selected by changing the setup, and one of the inspections is performed. Inspection can be performed with a focus on the target area.

The inspection unit 5 inspects the surface state of the substrate W based on the image captured by the imaging unit 4. At this time, the inspection unit 5 captures an image of the first surface S1 or the second surface S2 of the substrate W and inspects the surface state thereof. Specifically, the inspection unit 5 can be configured by a so-called image processing device (hardware) and an image processing program (software). Then, after the video signal and image data output from the imaging camera 42 and the imaging camera 47 are input to the image processing apparatus IM, the inspection unit 5 performs predetermined image processing, and sets a predetermined inspection standard. Based on the inspection.

Specifically, the inspection unit 5 detects the bright spot included in the image, determines the particle size as a foreign substance from the brightness information of each bright spot, the number of occupied pixels, and the like, performs a labeling process, and how large the size is. An inspection (so-called foreign object detection inspection) is performed to determine how many foreign substances having a particle size of 5 are present.

The relative movement unit 6 moves the illumination unit 3 and the imaging unit 4 relative to the substrate W to be inspected.

Specifically, the relative moving unit 6 can be realized by using a so-called XY stage, and is attached on the apparatus frame 11 to move the slider in the X direction at a predetermined speed and to stop at a predetermined position. An axis stage 61 and a Y-axis stage 62 mounted on the slider of the X-axis stage 61 and moving the slider in the Y direction at a predetermined speed and stopping at a predetermined position are configured. On the slider of the Y-axis stage 62, the substrate mounting table 20 is attached. By doing so, the illumination unit 3 and the imaging unit 4 can be moved relative to the substrate W placed on the substrate mounting table 20, and the entire substrate W is imaged and inspected by being divided and scanned a plurality of times. be able to.

Further, if necessary, a configuration in which a rotary table mechanism is provided between the slider of the Y-axis stage 62 and the substrate mounting table 20 may be used. By doing so, it is possible to change the angle of the substrate W, correct the positional deviation of the substrate W, and change the direction of imaging / inspection and receipt / delivery of the substrate to 90 degrees, 180 degrees, and 270 degrees. Can be.

FIG. 2 is a conceptual diagram showing a state in which the front and back surfaces of a substrate thinner than the conventional one are inspected by using the substrate inspection apparatus embodying the present invention, and the substrate to be inspected is irradiated with illumination light to the substrate. The state of imaging scattered light that has been diffusely reflected by an attached foreign object and the intensity of the captured scattered light are illustrated in a composite manner. The illumination light 32 irradiated from the illumination unit is irregularly reflected on the surface of the foreign matter X1 attached to the front surface side of the substrate W and the surface of the foreign matter X2 attached to the back surface side of the substrate WW (thickness: t). The image is captured by the imaging camera 42 of the imaging unit 4. In this case, the observation unit 4 is arranged at a predetermined angle θ1 with respect to the normal H1 on the surface side of the substrate W (that is, the first surface S1 side).

In applying the present invention, the light sheet-like illumination light thickness 32t (that is, the width in the XZ direction) is 1/3 or less (preferably 1/4 or less) of the thickness of the substrate W to be inspected. ). This is because the illumination light is made sufficiently thin relative to the thickness of the substrate W so that the same surface (the first surface when the first surface is inspected) or the opposite side (the first surface). It is possible to prevent scattered light from other foreign substances existing on the second surface) at the time of inspection from being simultaneously imaged and obtain a desired inspection result.

Since it has such a configuration, an image acquired by imaging the front side of the substrate (that is, the first surface S1 side) by inspecting using the substrate inspection apparatus 1 is the back side ( That is, the predetermined inspection can be performed without being affected by the state on the second surface S2 side. Furthermore, the image acquired by imaging the back side of the substrate (that is, the second surface S2 side) is not affected by the state of the surface side of the substrate (that is, the first surface S1 side), and is subjected to a predetermined inspection. It can be performed. Therefore, even if the inspection target substrate becomes thin, the inspection accuracy can be maintained by separating the front and back.

[Another form]
In the above description, as an embodiment of the present invention, the substrate inspection apparatus 1 having a configuration in which the imaging unit 4 includes a pair of the imaging camera 42 and the lens 43 has been exemplified. However, the present invention can also be embodied using the substrate inspection apparatus 1B having the following configuration.

That is, the substrate inspection apparatus 1B has a basic configuration similar to that of the substrate inspection apparatus 1, but includes an imaging unit 4B and an inspection unit 5B instead of the imaging unit 4 and the inspection unit 5. The imaging unit 4B is configured to include a substrate first surface side imaging unit 41 and a substrate second surface side imaging unit 46 separately.

The substrate first surface side imaging unit 41 observes the first surface side inspection target region set on the first surface S1 side of the substrate W from the first surface S1 side. The substrate first surface imaging unit 41 is arranged to image the first surface-side inspection target region V1 at a predetermined angle θ1 with respect to the normal H1 of the first surface S1 of the substrate. .

The substrate second surface side imaging unit 46 sets the second surface side inspection target region set on the second surface S2 side opposite to the first surface S1 of the substrate W from the first surface S1 side. The image is taken. And the board | substrate 2nd surface imaging part 46 is arrange | positioned so that the predetermined angle (theta) 1 may be made with respect to the normal line H1 of the 1st surface S1 of the said board | substrate, and 2nd surface side inspection object area | region V2 may be imaged. .

Specifically, the board first surface imaging unit 41 is configured to include an imaging camera 42 and a lens 43 similar to the imaging unit 4 described above, and the board second surface imaging unit 46 is configured with the imaging camera 42. A similar imaging camera 47 and a lens 48 similar to the lens 43 are included.

If there is no change in the type of the substrate W (that is, if the thickness and refractive index are constant), the imaging camera 42 of the substrate first surface side imaging unit 41 and the imaging camera of the substrate second surface side imaging unit 46 will be described. 47 is fixed to each other. On the other hand, when there is a product type change of the substrate W (that is, the thickness or the refractive index is not constant), at least one of the imaging cameras 42 and 47 passes through a mechanism that changes the position in the thickness direction of the substrate W. It is good also as a structure attached to the apparatus flame | frame 15.

In the case of this embodiment, the inspection unit 5B has the same basic configuration as the above-described inspection unit 5, but images both the first surface S1 and the second surface S2 of the substrate W, and their surface states. It is set as the structure which inspects.

[Another form]
In the above description, the relative movement unit 6 that moves the illumination unit 3 and the imaging unit 4 relative to the substrate to be inspected is provided.
The imaging unit 4 includes a line sensor having a predetermined length in a direction orthogonal to the direction of relative movement,
The illumination unit 3 has been described with respect to a configuration that irradiates a light sheet-like illumination light onto an inspection target region imaged by a line sensor.

With this configuration, inspection can be performed using a line sensor with high resolution, and the irradiation range of illumination light can be minimized, so that cost reduction and size reduction are facilitated. Furthermore, the scattered light from other foreign substances existing on the same surface (first surface when inspecting the first surface) or on the opposite side (second surface when inspecting the first surface) is simultaneously imaged. Therefore, it is possible to prevent a problem that a desired inspection result cannot be obtained correctly.

However, in order to embody the present invention, the present invention is not limited to this configuration, and the following configuration may be used.
That is, an area sensor is used for the imaging unit 4, and the illumination unit 3 is configured to irradiate illumination light to a range including an inspection target region imaged by the area sensor. In this case, the illumination unit 3 and the imaging unit 4 are relatively moved with respect to the substrate W to be inspected, and the illumination light is stroboscopically emitted to repeat imaging (so-called divided imaging), or the illumination light is continuously applied. It is set as the structure which image-shoots intermittently (it is also a kind of division | segmentation imaging), irradiating. Or it is good also as a structure which is not provided with a relative movement part and image | photographs test object area | region R collectively using an area sensor camera.

[Another form]
In embodying the present invention, the illuminating unit 3 is arranged so that the illumination light is irradiated within a range of 10 to 20 degrees with respect to the normal H1 of the first surface S1 of the substrate W. The imaging camera 42 of the imaging unit 4 is arranged so that the angle θ1 with respect to the normal H1 of the first surface S1 of the substrate W is set within a range of 40 to 80 degrees and the inspection target region is observed. Preferably it is.

As the set angle θ1 of the imaging unit 4 becomes smaller than 90 degrees, the front / back separation characteristics are improved. However, if it is too small (inclined), the surface reflection component on the first surface S1 increases, and the amount of light necessary for the inspection of the second surface S2 decreases. Therefore, the angle θ1 for inclining the imaging unit 4 is preferably within the above-described range.

With such a configuration, the scattered light can be accurately imaged without being affected by regular reflection. Furthermore, when performing the inspection on the second surface side, the inspection accuracy can be maintained by separating the front and back without causing a decrease in the amount of light.

Note that if the imaging unit 4B has a configuration in which the substrate first surface side imaging unit 41 and the substrate second surface side imaging unit 46 are separately provided, the imaging cameras 42 and 47 both have the first of the substrate W. It is preferable that the angle of the surface S1 with respect to the normal H1 is set within a range of 40 to 80 degrees and the inspection target region is observed.

[Another form]
The substrate holding unit 2 is not limited to the above-described configuration, and can be configured by substrate mounting tables 20B and 20C as shown in FIG. FIG. 3 is a cross-sectional view showing a variation of the substrate holding portion constituting the present invention.
FIG. 3A is a cross-sectional view of the substrate mounting table 20 described above. The substrate mounting table 20 is provided with a recess 22 below the surface of the substrate W to be inspected. The substrate mounting table 20 is configured to support the outer periphery of the substrate W from below.

3B has a so-called drop-in structure in which there is a recess 23 in the outer peripheral portion of the substrate instead of the positioning reference pin 21. The substrate mounting table 20B shown in FIG. Similar to the substrate mounting table 20 described above, a recess 22 is provided below the surface of the substrate W to be inspected.

The substrate mounting table 20C shown in FIG. 3C is configured to support the lower surface of the substrate W with a large number of support pins 25.

The relative movement unit 6 is not limited to the above-described configuration, but is configured to transfer the substrate W using a rotating roller (so-called conveyor transfer), or configured to transfer using a walking beam and a gripping unit ( So-called shuttle transport) may be used.

DESCRIPTION OF SYMBOLS 1 Substrate inspection apparatus 2 Substrate holding part 3 Illumination part 4 Imaging part 5 Inspection part 11 Apparatus frame 15 Connecting member 20 Substrate mounting table 20B Substrate mounting table 20C Substrate mounting table 21 Positioning reference pin 22 Recess 23 Recess 25 Support pin 31 Light sheet illumination Unit 32 Light sheet-like illumination light 32t Light sheet-like illumination light thickness 41 Substrate first surface side imaging unit 42 Imaging camera 42z Imaging camera 43 Lens 43z Lens 44 Imaging element 46 Substrate second surface side imaging unit 47 Imaging camera 48 Lens 49 Image sensor R Inspection target region W Substrate S1 First surface of substrate S2 Second surface of substrate θ1 Predetermined angle (angle of imaging camera of substrate first surface imaging unit)
θ2 Predetermined angle (angle of the imaging camera of the substrate second surface imaging unit)
X1 Foreign object X2 Foreign object

Claims

A substrate holding unit for holding a substrate to be inspected;
An illumination unit that irradiates illumination light toward the inspection target region set on the substrate;
An imaging unit for imaging the inspection target region;
An inspection unit that inspects the surface state of the substrate based on an image captured by the imaging unit;
The illumination unit is arranged to irradiate light sheet-like illumination light at a predetermined angle with respect to the normal line of the first surface of the substrate,
The imaging unit
A first surface side inspection object region set on the first surface side of the substrate or a second surface side inspection object region set on the second surface side opposite to the first surface of the substrate; An imaging unit that images from the first surface side of the substrate,
The said imaging part is a board | substrate inspection apparatus arrange | positioned at a predetermined angle with respect to the normal line of the 1st surface of the said board | substrate.
A substrate holding unit for holding a substrate to be inspected;
An illumination unit that irradiates illumination light toward the inspection target region set on the substrate;
An imaging unit for imaging the inspection target region;
An inspection unit that inspects the surface state of the substrate based on an image captured by the imaging unit;
The illumination unit is arranged to irradiate light sheet-like illumination light at a predetermined angle with respect to the normal line of the first surface of the substrate,
The imaging unit
A substrate first surface side imaging unit for observing a first surface side inspection target region set on the first surface side of the substrate from the first surface side;
A substrate second surface side imaging unit configured to image from the first surface side a second surface side inspection target region set on the second surface side opposite to the first surface of the substrate;
The substrate first surface imaging unit and the substrate second surface imaging unit are arranged so as to image the first surface side inspection target region at a predetermined angle with respect to a normal line of the first surface of the substrate. ing,
Board inspection equipment.
A relative movement unit that moves the illumination unit and the imaging unit relative to the substrate;
The imaging unit includes a line sensor having a predetermined length in a direction orthogonal to the relatively moving direction,
The substrate inspection apparatus according to claim 1, wherein the illumination unit irradiates the light sheet-shaped illumination light onto an inspection target region imaged by the line sensor.
The illumination unit is arranged such that illumination light is irradiated within a range of 10 to 20 degrees with respect to a normal line of the first surface of the substrate,
The imaging unit is arranged so that an angle with respect to a normal line of the first surface of the substrate is set within a range of 40 to 80 degrees and the inspection target region is observed. 4. The substrate inspection apparatus according to any one of 1 to 3.