TW201632868A - Substrate examination device - Google Patents

Abstract

Provided is a substrate examination device such that even if a substrate to be examined becomes thin, the device can exam the front surface-side and the rear surface-side of the substrate, separately for the front and the rear, and do so with high accuracy and quickly. More specifically, the substrate examination device is provided with the following: a substrate retaining part; an illumination unit; a splitting and polarizing unit; an S polarization image pickup unit; a P polarization image pickup unit; and a foreign matter examination unit. The foreign matter examination unit is provided with a foreign matter adhered surface determination unit that compares the results of image pickup by the S polarization image pickup unit and examination and the results of image pickup by the P polarization image pickup unit and examination, and from the magnitude relation of scattered light intensity at the same position on the substrate to be examined, determines whether foreign matter has adhered to either the front surface-side or the rear surface-side of the substrate to be examined.

Description

Substrate inspection device

The present invention relates to an apparatus for optically inspecting the presence or absence of defects such as foreign matter or damage attached to the front side or the back side of a transparent body (so-called substrate) such as a glass substrate.

In the surface defect inspection of the conventional liquid crystal panel, the detection optical system was disposed symmetrically on each of the front side and the back side of the substrate, and the defects on the front side and the defects on the back side were separately examined. (for example, Patent Document 1).

In addition, the following technique is applied to illuminate linear illumination light obliquely from the inspection target substrate, and the imaging optical system having a depth of focus smaller than the thickness of the inspection target substrate is disposed at a light receiving angle of 90 degrees with respect to the front surface of the substrate. On the other hand, the inspection can be performed at one time without confusing the front side and the back side of the inspection target substrate (for example, Patent Document 2).

Fig. 10 is a perspective view showing an example of a conventional substrate inspection apparatus. In the previous inspection apparatus 1z, the illumination light 32z is irradiated from the illumination unit 3z toward the inspection target region Rz of the substrate Wz to be inspected, and the imaging camera 42z and the lens 43z disposed in the imaging unit 4z disposed above the substrate Wz are imaged. The scattered light emitted by the area Rz is checked based on the captured image. Further, the substrate Wz is held on the substrate stage 20, and the substrate stage 20 is mounted on the X-axis stage 61 and the Y-axis stage 62 mounted on the apparatus frame 11z, and is movable at a specific speed in the XY direction. The specific location stops. In addition, the imaging camera 42z is attached to 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, the direction perpendicular to the front surface of the substrate Wz). Therefore, the substrate Wz can be opposed to the imaging portion 4z (that is, the substrate Wz as a whole) The image is cut and divided by dividing into a plurality of X directions and repeating the scanning operation at a fixed speed in the Y direction.

At this time, in the imaging unit 4, first, scanning and imaging are performed in a state where the front side of the substrate Wz is focused, and then scanning and imaging are performed while focusing on the back side of the substrate Wz. That is, in the previous substrate inspection apparatus 1z, the so-called second scanning is performed to perform inspection.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 3-188491

[Patent Document 2] Japanese Patent No. 4104924

[Patent Document 3] Japanese Patent Laid-Open No. Hei 5-52762

When it is desired to quickly check for the presence of defects such as foreign matter or damage on the front side and the back side of the substrate to be inspected, if it is a device that requires two sets of optical systems for inspection as shown in Patent Document 1, This leads to an increase in cost or an increase in size of the inspection device itself.

On the other hand, in the case where one inspection optical system is provided, and the apparatus for inspecting the front side and the back side of the inspection target substrate separately can be photographed and inspected in one scan, as shown in the patent document 2 At this time, if the inspection target substrate becomes thinner (for example, if the thickness becomes thinner than 0.4 mm), it is difficult to separate the front and back due to the reason described below.

FIG. 11 is a conceptual view showing a state in which the front and back surfaces of the substrate are inspected using the conventional substrate inspection device, and the substrate Wz to be inspected is irradiated with the illumination light 32z in a composite manner, and is photographed on the foreign matter attached to the substrate. The case of the scattered light reflected and the intensity of the scattered light from the foreign objects X1 and X2 captured by the imaging unit. Again, the map 11(a) shows the case where the substrate Wz (thickness tz: 0.5 to 0.7 mm) which has been inspected since the previous inspection is performed, and FIG. 11(b) shows the substrate W (thickness t: 0.4 mm) which is thinner than the previous one. The following is the case for inspection. The illumination light 32z irradiated from the illumination unit is diffused and reflected on the surface of the foreign matter X1 adhering to the front side of the substrates Wz and W and the foreign matter X2 adhering to the back side of the substrates Wz and W, respectively, and the scattered light passes through the imaging unit 4z. The lens 43z is imaged and photographed by the camera camera 42z.

In the case of the previous substrate Wz, the scattered light of the foreign material X1 on the front side and the foreign matter X2 on the back side are respectively imaged at the separated position, so that the detection can be performed in the separated state. However, in the case of the substrate W which is thinner than the previous one, the foreign matter X1 on the front side and the scattered light X2 on the back side overlap with each other, and thus it is difficult to detect separately.

Further, in the configuration shown in Patent Document 3, the light receiving angle of the light receiving system is set to be about 80 degrees with respect to the normal line of the front surface of the substrate. However, in this case, since the scattered light from the back surface side of the substrate is reflected by the inner surface of the substrate, the light observed by the light receiving system becomes extremely weak, and it is difficult to stably inspect the foreign matter on the back side.

In view of the above, it is an object of the present invention to provide a substrate inspection apparatus capable of inspecting the front side and the back side of a substrate with high precision and speed, even when the inspection target substrate is thinned.

In order to solve the above problems, the present invention provides a substrate inspection apparatus including: a substrate holding portion that holds a substrate to be inspected; and an illumination portion that irradiates illumination light toward an inspection target region set on the substrate; and separates the polarizing portion. The S-polarized imaging unit captures the S-polarized light that is separated from the scattered light, and the P-polarized imaging unit And photographing the separated P-polarized light of the scattered light; And a foreign matter inspection unit that checks a position and a size of a foreign matter attached to a front side or a back side of the substrate to be inspected based on an image captured by the S-polarized image capturing unit and the P-polarized image capturing unit; The foreign matter inspection unit is provided with a foreign matter attachment surface determination unit that compares the result obtained by the S-polarization imaging unit and the result of the inspection, and the result of the inspection by the P-polarization imaging unit. Based on the magnitude relationship of the scattered light intensity at the same position on the substrate to be inspected, it is determined which of the front side or the back side of the substrate to be inspected is attached to the object to be inspected.

According to this configuration, light that is separated into the S-polarized state and the P-polarized state is imaged once on the front side and the back side of the substrate to be inspected, and the S-polarized component can be determined as the portion of the scattered light emitted from the substrate. If it is strong, foreign matter is present on the front side, and if the P-polarized component is strong, foreign matter is present on the back side. Furthermore, this determination is based on the physical phenomenon of the interface between substances having different refractive indices (ie, the substrate material and the environment around them), and can be applied even if the thickness of the substrate is thin.

Further, according to the configuration described above, it is possible to determine which of the foreign matter at the same position that is photographed at one time is attached to the front side or the back side of the substrate, so that erroneous detection such as erroneous counting or double counting can be prevented. In other words, it is only necessary to perform one-time imaging for the same inspection target portion, so that a quick inspection can be performed.

Even if the inspection target substrate is thinned, the front side and the back side of the substrate can be inspected with high precision and speed with respect to the front and back separation.

1‧‧‧Substrate inspection device

1z‧‧‧Previous substrate inspection device

2‧‧‧Substrate retention department

3‧‧‧Lighting Department

3B‧‧‧Lighting Department

3z‧‧‧Lighting Department

4‧‧‧Photography Department

4p‧‧‧P Polarized Camera

4s‧‧‧S polarized camera

4z‧‧·Photography Department

5‧‧‧ Separation of polarized parts

5B‧‧‧ Separation of polarized parts

7‧‧‧ Foreign Body Inspection Department

8‧‧‧ Relative Mobile Department

11‧‧‧ device framework

11z‧‧‧ device framework

15‧‧‧Connected components

15z‧‧‧Connected components

20‧‧‧Substrate mounting table

21‧‧‧ Positioning reference pin

31‧‧‧Lighting unit

32‧‧‧Lights

32z‧‧‧Lights

33‧‧‧Arrows (light forward)

35‧‧‧Mirror

36‧‧‧ illumination light (light reflected by mirror)

42p‧‧‧ camera (for P-polarization inspection)

42s‧‧‧ Camera Camera (for S-polarization inspection)

42z‧‧‧ camera camera

43‧‧‧ lens

43p‧‧‧Lens (for P-polarization inspection)

43s‧‧‧Lens (for S-polarization inspection)

43z‧‧ lens

44‧‧‧Connect

50‧‧‧Polarizing beam splitter

50B‧‧·half mirror

51a‧‧‧Scattered light from foreign object X1

51b‧‧‧ part of the incident light

51c‧‧‧ part of the incident light

51p‧‧‧scattered light from foreign matter X1 by P-polarized light

51p', 52p'‧‧‧Light through P-polarized filter

51s‧‧‧Scattered light from foreign matter X1 by S-polarization

51s', 52s' ‧ ‧ light through S polarizing filter

52a‧‧‧Scattered light from foreign body X2

52b‧‧‧ part of the incident light

52c‧‧‧ part of the incident light

52p‧‧‧scattered light from foreign matter X2 via P-polarized light

52s‧‧‧Scattered light from foreign matter X2 by S-polarization

54p‧‧‧P polarizing filter

54s‧‧‧S polarizing filter

61‧‧‧X-axis platform

62‧‧‧Y-axis platform

81‧‧‧X-axis platform

82‧‧‧Y-axis platform

H1‧‧‧ normal

R‧‧‧ inspection area

R1‧‧‧ inspection area (1st main side)

R2‧‧‧ inspection area (2nd main side)

Rz‧‧‧ inspection area

The first main surface of the S1‧‧‧ substrate (front side of the substrate)

S2‧‧‧2nd main surface of the substrate (back side of the substrate)

T‧‧‧thickness

Tz‧‧‧ thickness

W‧‧‧Substrate

Wz‧‧‧ substrate

X1‧‧‧ Foreign objects

X2‧‧‧ Foreign objects

X3‧‧‧ Foreign objects

X4‧‧‧ Foreign objects

X‧‧‧X axis

Y‧‧‧Y axis

Z‧‧‧Z axis

θ1‧‧‧Specific angle (angle of polarized illumination)

Θ2‧‧‧specific angle (angle of camera)

Fig. 1 is a perspective view showing an example of a form for realizing the present invention.

Figure 2 is a composite view showing the main part of an embodiment of the present invention and photographing A plot of the intensity of the scattered light.

3(a) and 3(b) are correlation diagrams for comparing scattered light intensities from foreign matter attached to the front and back surfaces of the substrate.

Fig. 4 is a flow chart showing the inspection process for realizing an embodiment of the present invention in time series.

Fig. 5 is a plan view showing an example of a substrate to be inspected in an example of the embodiment of the present invention.

Fig. 6 (a) to (d) are conceptual views showing an example of the results obtained by inspection in an example of the embodiment of the present invention.

Fig. 7 is a perspective view showing another example of the embodiment of the present invention.

Fig. 8 is a view showing, in combination, a main part of another example for realizing the embodiment of the present invention and a captured scattered light intensity.

Fig. 9 is a front elevational view showing the main part of still another example of the embodiment of the present invention.

Fig. 10 is a perspective view showing an example of a conventional substrate inspection apparatus.

11(a) and 11(b) are conceptual views showing a state in which the front and back sides of the substrate are inspected using the previous substrate inspection device.

The drawings will be described with reference to the drawings for carrying out the invention.

Fig. 1 is an external view showing an example of a form for realizing the present invention.

In FIG. 1, a substrate inspection apparatus 1 that performs optical inspection based on an image obtained by photographing a substrate is collectively described with a perspective view of each constituent device and a configuration necessary for acquiring an image and performing inspection. In addition, in each figure, the three axes of the orthogonal coordinate system are set to X, Y, and Z, the XY plane is set to a horizontal plane, and the Z direction is set to a vertical direction. In particular, the direction of the arrow is set to the upper direction in the Z direction, and the opposite direction is expressed as the lower side. Moreover, the substrate W to be inspected has the first main surface S1 and the second main surface S2 which is in front and back relationship with the first main surface S1. Furthermore, in the present case, the first main surface S1 side is called The first main surface side or the front side is referred to as a second main surface side or a back side in the relationship between the front surface and the back surface. In addition, the first main surface side which is set in the inspection target region R of the substrate W is referred to as a first main surface side inspection target region R1, and the second main surface side is referred to as a second main surface side inspection target region R2. In addition, the inspection target region R set on the substrate W is set for each size or type of the substrate, and a specific region on the substrate or the entire surface of the substrate other than the peripheral portion can be set.

The substrate inspection device 1 that realizes an embodiment of the present invention includes a substrate holding unit 2, an illumination unit 3, a separation polarizing unit 5, an S polarization imaging unit 4s, a P-polarized imaging unit 4p, and a foreign object inspection unit 7. The substrate inspection apparatus 1 irradiates the illumination light toward the inspection target region R set to the substrate W, and separates the scattered light from the foreign matter located in the inspection target region R into the S-polarized state and the P-polarized state, respectively. The light in the polarized state and the P-polarized state individually acquires a captured image, and the foreign matter inspecting unit 7 extracts the foreign matter. Further, in the foreign matter inspection unit 7, the intensity of the scattered light when the light in the S-polarized state is captured and the intensity of the scattered light when the light in the P-polarized state is captured are compared with respect to the extracted foreign matter, and the foreign matter is determined to be located on the substrate according to the magnitude relationship. W is on the first main surface S1 side (that is, on the front side) or on the second main surface S2 side (that is, on the back side). Further, the substrate inspection apparatus 1 may be configured to include the relative movement unit 8 as needed.

The substrate holding portion 2 holds the substrate W to be inspected.

Specifically, the substrate holding portion 2 can be configured by the substrate placing table 20 . The substrate mounting table 20 has a shape slightly smaller than the outer surface of the substrate W and has a cavity or a recessed cross-sectional shape outside the portion of the substrate W which is the inspection target region. Moreover, the substrate mounting table 20 is provided with the positioning reference pin 21 on the outer side slightly outside the substrate W.

The illumination unit 3 illuminates the illumination light 32 toward the inspection target region R set on the substrate W. Specifically, the illuminating unit 3 can be exemplified by a lamp light source such as a xenon lamp, a halogen lamp, or a metal halide lamp, or a semiconductor laser or an LED (Light Emitting Diode), and the like, and a lens, a mirror, or the like. The illumination light is illuminated toward the inspection target area.

Here, a configuration in which a xenon lamp is used as the illumination unit 3 will be described. Further, an illuminating light is irradiated from the illuminating unit 3 toward the inspection target region R in an elongated strip shape (so-called sheet shape), and a line sensor is provided as an imaging camera in the imaging unit 5 described below. element.

The illumination unit 3 includes a light source unit, a light guiding fiber unit, and an illumination unit 31.

The light source unit (not shown) includes a xenon lamp, a power source for causing the xenon lamp to emit light, and an elliptical mirror for efficiently reflecting the emitted light. The light guiding fiber portion is provided with a bundle of optical fibers that guide light emitted from the light source portion to the outside. The illumination unit 31 is provided with a cylindrical lens inside, and can irradiate the guided light to the inspection target region R as sheet light.

The separation polarizing unit 5 separates the scattered light into light in a S-polarized state and light in a P-polarized state. Specifically, the polarizing unit 5 includes an optical element called a polarization beam splitter 50. The polarization beam splitter 50 can be configured by combining an optical element such as a crucible to which a multilayer film coating is applied, and passing the light of the P-polarized component in the incident light straight, and reflecting the light of the S-polarized component (ie, bending the optical path 90) Degree) and pass.

Fig. 2 is a view showing, in combination, a main part of an embodiment of the present invention and a captured scattered light intensity. 2 is a conceptual view showing a case where a substrate inspection apparatus embodying the present invention is used to inspect a front surface and a back surface of a substrate which is thinner than before, and a substrate W to be inspected is collectively illuminated to emit illumination light and imaged and attached thereto. The scattered light of the foreign matter X1 and X2 of the substrate W is diffusely reflected, and the intensity of the scattered light from the foreign matter X1 and X2 captured by the imaging unit.

The illumination unit 31 is disposed such that the illumination light 32 for inspection is irradiated with the illumination light 32 at a specific angle θ1 with respect to the normal line H1 of the first principal surface S1 of the substrate W and in the direction of the arrow 33. That is, the illumination light 32 is irradiated obliquely upward from the first main surface S1 of the substrate W. Further, the illumination light 32 is respectively attached to the surface of the foreign matter X1 on the first main surface side of the substrate W and the surface of the foreign matter X2 adhering to the second main surface side of the substrate W (that is, the second main surface side of the substrate W). Diffuse reflection, such as scattered light is separated into S-polarized state and P-polarized by separating the polarizing section 5 The light state is captured by the S polarized light imaging unit 4s and the P polarized light imaging unit 4p.

Therefore, the polarization beam splitter 50 can separate the scattered light 51a and 52a emitted from the foreign matter X1 and X2 attached to the inspection target region R into the light 51s and 52s which are in the S-polarized state, and the light 51p which is in the P-polarized state. , 52p. In addition, the S-polarized light refers to light that travels while oscillating in the horizontal direction (ie, the X direction). On the other hand, the P-polarized light refers to light that travels while oscillating in a direction orthogonal to the horizontal direction (ie, the X direction) and the direction in which the light advances. In addition, the S-polarized state is not limited to a state in which light of only the S-polarized component is completely limited, and is a state in which light containing a small amount of P-polarized component is used and light of the S-polarized component is mainly composed. In the same manner, the P-polarized state is not limited to the state of completely forming only the light of the P-polarized component, but is a state in which the light of the S-polarized component is included and the light of the P-polarized component is the main component.

Further, the ratio of the light in the P-polarized state to the light in the S-polarized state by the polarization beam splitter can be appropriately set by the material or film thickness of the multilayer film coating, and the example of separation by 1:1 is shown here ( Refer to Figure 1).

The S-polarized image capturing unit 4s is a light that is separated from the scattered light by the separation polarizing unit 5 and is set to the S-polarized state among the scattered light emitted from the inspection target region. The P-polarized light-receiving unit 4p is a light that is separated from the scattered light by the separation polarizing unit 5 and is set to a P-polarized state among the scattered light emitted from the inspection target region. Specifically, the S-polarized image capturing unit 4s and the P-polarized light-receiving unit 4p are imaged on the first main surface side inspection target region R1 set on the first main surface S1 side of the substrate W from the first main surface S1 side or set on the substrate W. The second main surface side inspection target region R2 on the second main surface S2 side. Further, the separation polarizing unit 5 and the P-polarized imaging unit 4p are arranged such that the first main surface side inspection target region R1 is imaged at a specific angle θ2 with respect to the first main surface S1 of the substrate W, and the S-polarized imaging unit 4s is configured. The first main surface side inspection target region R1 is placed by bending the optical path by 90 degrees and separating the polarizing portion 5 . In other words, the S-polarized image capturing unit 4s and the P-polarized light-receiving unit 4p are configured to image the inspection target region R from the obliquely upper side of the first main surface S1 of the substrate W.

More specifically, the S-polarized image capturing unit 4s includes an imaging camera 42s and a lens 43s. On the other hand, the P-polarized light imaging unit 4p includes an imaging camera 42p and a lens 43p. The image pickup camera 42s and 42p output an image signal or image data corresponding to the image received by the image pickup device to the outside. As the image pickup device, a CCD (Charge Coupled Device) or a CMOS (Complementary) can be exemplified. Metal Oxide Semiconductor, a complementary metal oxide semiconductor linear sense sensor. The lenses 43s and 43p collect the scattered light from the foreign matter attached to the substrate W on the imaging elements of the imaging cameras 42s and 42p to form an image.

Furthermore, the imaging elements of the camera cameras 42s and 42p are not limited to the line type sensor, and may be a TDI (Transport Driver Interface) sensor. Alternatively, the imaging elements of the camera cameras 42s and 42p may also employ a surface sensor.

The S-polarized image capturing unit 4s and the P-polarized light-receiving unit 4p are configured such that the depth of field of the lenses 43s and 43p is equal to or greater than the thickness t of the substrate W, and the distance from the substrate W is fixed via the connecting member 15 in a state where the distance from the substrate W is fixed. Mounted to the device frame 11. At this time, the S-polarized image capturing unit 4s and the P-polarized light-receiving unit 4p are in a state in which the first main surface S1 of the substrate W and the second main surface S2 of the substrate W are in focus.

Fig. 3 is a correlation diagram comparing the intensity of scattered light from foreign matter attached to the front and back surfaces of the substrate. In FIG. 3( a ), the standard particles having different particle diameters as foreign substances are attached only to the first main surface S1 side of the substrate W, and the S-polarized component and the P-polarized component of the illumination light for inspection are used. The intensity of the scattered light when the intensity is the same as that of the S-polarized imaging unit 4s and the P-polarized imaging unit 4p. On the other hand, in FIG. 3(b), the standard particles having different particle diameters as foreign substances are attached only to the side of the back surface S2 of the substrate W, and the S-polarized component and the P-polarized component of the illumination light for inspection are respectively shown. The intensity of the scattered light is the same as that of the S-polarized imaging unit 4s and the P-polarized imaging unit 4p.

At this time, the light is directed from the illumination unit 3 with respect to the normal line H1 of the first main surface S1 of the substrate W. The angle θ1 of the light 32 to be irradiated by the inspection target region R is within 80 degrees ± 5 degrees, and the illumination unit 3 and the separation polarization unit 5 are disposed such that the angle θ2 captured by the imaging camera 42 is within 45 degrees ± 5 degrees. Each of the S polarized light imaging unit 4s and the P polarized light imaging unit 4p.

3(a) and (b), it is understood that the scattered light intensity in the S-polarized state is stronger than the scattered light intensity in the P-polarized state as long as the foreign matter adheres to the front surface S1 side of the substrate W even if the particle diameter is different. On the other hand, it is understood that the scattered light intensity in the P-polarized state is stronger than the scattered light intensity in the S-polarized state as long as the foreign matter adheres to the back surface S2 side of the substrate W even if the particle diameter is different.

Therefore, as shown in FIG. 2, the scattered light 51a from the foreign matter X1 attached to the first principal surface of the substrate W is strong in the S-polarized component, and the intensity of the P-polarized component is weak. Therefore, the intensity of the S-polarized light 51s separated by the polarization beam splitter 50 is stronger than the intensity of the separated P-polarized light 51p. On the other hand, the scattered light 52a from the foreign matter X2 attached to the second principal surface of the substrate W is strong in the intensity of the P-polarized component, and the intensity of the S-polarized component is weak. Therefore, the intensity of the light 52p in the P-polarized state separated by the polarization beam splitter 50 is stronger than the intensity of the light 52s in the S-polarized state in which the separation is performed.

Furthermore, such characteristics are based on physical phenomena at the interface of substances having different refractive indices (i.e., the substrate material and the environment around them), even if the thickness of the substrate W is thin.

The foreign object inspection unit 7 checks the first main surface S1 side (ie, the front side) and the second main surface S2 side of the substrate W based on the images captured by the S polarized light imaging unit 4s and the P polarized light imaging unit 4p ( That is, the position and size of the foreign matter on the back side. Further, the details of the foreign matter inspection unit 7 are described below, and it is determined that the detected foreign matter is located on the first main surface S1 side (ie, the front side) of the substrate W or on the second main surface S2 side (that is, the back side).

The foreign matter inspection unit 7 includes an S-polarized image inspection unit, a P-polarized image inspection unit, an inspection result comparison unit, and a foreign matter attachment surface determination unit.

The S-polarized image inspection unit detects foreign matter based on an image obtained by separating the light of the S-polarized state of the polarizing unit 5 (that is, an image output from the imaging camera 42s).

The P-polarized image inspection unit detects the foreign matter based on the image obtained by the light of the P-polarized state in which the polarizing unit 5 is separated (that is, the image output from the imaging camera 42p).

Further, the S-polarized image inspection unit and the P-polarized image inspection unit perform calculation processing for obtaining the position or size of the detected foreign matter as needed, and output the result as an inspection result.

The inspection result comparison unit compares the inspection results of the S-polarized image inspection unit and the P-polarized image inspection unit.

The foreign matter adhering surface determining unit determines which of the positive side or the back side of the substrate to be inspected is attached to the foreign object. Specifically, the foreign matter adhering surface determining unit compares the intensity of the scattered light at the same position on the substrate to be inspected by the inspection result comparing unit.

If the intensity of the scattered light in the S-polarized state is > the intensity of the scattered light in the P-polarized state, it is determined that the foreign matter adheres to the front side of the substrate to be inspected.

When the intensity of the scattered light in the P-polarized state is the intensity of the scattered light in the S-polarized state, it is determined that the foreign matter adheres to the back side of the substrate to be inspected.

More specifically, the foreign matter inspection unit 7 and the S-polarized image inspection unit, the P-polarized image inspection unit, the inspection result comparison unit, and the foreign matter attachment surface determination unit can be represented by a so-called image processing device (hardware) and Like a processing program (software). Further, after the video signal or the image data output from the imaging cameras 42s and 42p is input to the image processing apparatus, the S-polarized image inspection unit, the P-polarized image inspection unit, and the inspection result comparison unit of the foreign object inspection unit 7 are used. The foreign matter attachment surface determination unit performs inspection based on a predetermined inspection standard while performing specific image processing.

Specific image processing of the S-polarized image inspection unit and the P-polarized image inspection unit of the foreign matter inspection unit 7 may be exemplified by detecting bright spots included in the image, and according to brightness information of each bright spot or the number of occupied pixels. When it is determined that the particle diameter of the foreign matter is associated with the coordinate information in the imaging field of view, the labeling process is performed, and the foreign matter having a particle size of several sizes on the substrate is inspected (so-called foreign matter detection inspection). Furthermore, it will be The inspection result of the S-polarized image inspection unit is referred to as the S-polarization inspection result, and the inspection result by the P-polarized image inspection unit is referred to as a P-polarization inspection result.

By the inspection result comparison unit of the foreign matter inspection unit 7, the foreign matter marked and processed on the same coordinate on the substrate is read for the S-polarization inspection result and the P-polarization inspection result, and the S-polarization inspection result and P are compared for each. Which of the polarized light inspection results has a strong scattered light intensity.

The foreign matter adhering surface determining unit of the foreign matter detecting unit 7 processes the strong scattered light intensity as a foreign matter, and determines which of the first main surface S1 side or the second main surface S2 side of the substrate W is attached to the substrate W. on. Then, the foreign matter inspection unit 7 converts the intensity of the scattered light corresponding to the size of the foreign matter into the foreign matter particle diameter, and outputs it as a result of the foreign matter inspection. In addition, as a result of the S-polarization inspection result and the P-polarization inspection result, when the intensity of the scattered light is converted into a particle diameter and output as a result of the inspection, it is comparatively larger which particle diameter is larger.

[Processing by the Foreign Body Inspection Department]

Fig. 4 is a flowchart showing an inspection process for realizing an example of the present invention in time series, and shows an example of inspection processing by the foreign matter inspection unit of the present invention.

First, the substrate W to be inspected is placed on the substrate stage 20 (step s10).

Then, the illumination light 32 is irradiated from the illumination unit 31 toward the inspection target region R (step s11), and the scattered light from the foreign matter attached to the front surface of the substrate W is separated and polarized by the separation polarizing portion 5 (step s12).

Then, the image captured in the S-polarized state is acquired to the image processing apparatus (step s13), and the inspection is performed based on the image, and the inspection result (that is, the S-polarization inspection result) is acquired (step s14).

At the same time, the image captured in the P-polarized state is acquired to the image processing apparatus (step s15), and an inspection is performed based on the image, and the inspection result is acquired (ie, P-polarization inspection) Result) (step s16).

Then, in the image processing apparatus, the S-polarization inspection result and the P-polarization inspection result are compared (step s17). At this time, the imaging cameras 42s and 42p of the S-polarized imaging unit 4s and the P-polarized imaging unit 4p are disposed at an angle θ2 with respect to the normal line of the substrate W. Therefore, the position information of the detected foreign matter is not caused by the substrate. The thickness of W is shifted on the first main surface S1 side (that is, the front side) and the second main surface S2 side (that is, the back side), and the position is corrected in advance in the coordinate system of the substrate W in plan view.

Then, the foreign matter at the same position in the coordinate system of the substrate W is compared, and if the scattered light intensity in the S-polarized state is > the scattered light intensity in the P-polarized state, it is determined that the foreign matter adheres to the front side of the substrate. When the intensity of the scattered light in the P-polarized state is the intensity of the scattered light in the S-polarized state, it is determined that the foreign matter adheres to the back side of the substrate (step s18).

Then, if necessary, the inspection result of the surface state such as the size or the number of the foreign matter attached to the first main surface S1 side and the second main surface S2 side of the substrate W is output (step s19).

[Example of inspection object and inspection result]

Fig. 5 is a plan view showing an example of a substrate to be inspected in an example of the embodiment of the present invention. In FIG. 5, a large foreign matter X1 and a small foreign matter X2 are attached to the first main surface S1 side (ie, the front side) of the substrate W to be inspected, and the second main surface S2 side of the substrate W is attached ( That is, the back side is attached with a large foreign matter X3 and a small foreign matter X4.

Fig. 6 is a conceptual diagram showing an example of the results obtained by inspection in an example of the embodiment of the present invention. In Fig. 6(a), the captured image in the above step s13 (i.e., the S-polarized state) is shown, and in Fig. 6(b), the captured image in the above-described step s14 (i.e., the P-polarized state) is shown.

Further, in Fig. 6(c), the inspection results of the first main surface S1 side (i.e., the front side) of the substrate W outputted by the above-described step s18 are shown, and a large foreign matter X1 and a small foreign matter are adhered. The case of X3.

Further, in Fig. 6(d), the inspection results of the second main surface S2 side (i.e., the back side) of the substrate W outputted in the above step s18 are shown, and a large foreign matter X2 and a small foreign matter X4 are attached. The situation.

Further, as an example of the output of the inspection result, in the form of (c) and (d) of FIG. 6 , the foreign matter X1 to the fourth embodiment are illustrated on the XY coordinates of the substrate W. However, the present invention is not limited to this embodiment, and may be The form of output of numerical data.

The relative movement unit 8 maintains the positional relationship between the illumination unit 3, the separation polarization unit 5, the S polarization imaging unit 4s, and the P polarization imaging unit 4p, and relatively moves the substrate W to be inspected relative to the above. The illuminating unit 3, the S-polarized imaging unit 4s, and the P-polarized imaging unit 4p, which are configured to capture only a partial region of the substrate W, can be photographed by the scanning operation or the step-and-repeat operation. The inspection target area of the substrate W.

Specifically, the relative moving portion 8 can be realized by using a so-called XY stage, and is configured to include an X-axis stage 81 and a Y-axis stage 82 which are attached to the apparatus frame 11 and which are arranged in the X direction. Moving at a particular speed and stationary at a particular location, the Y-axis platform 82 is mounted on the slider of the X-axis platform 81 and moves the slider at a particular speed in the Y direction and is stationary at a particular location. A substrate mounting table 20 is mounted on the slider of the Y-axis stage 82. Thereby, the substrate W placed on the substrate stage 20 can be relatively moved with respect to the illumination unit 3, the separation polarization unit 5, the S polarization imaging unit 4s, and the P polarization imaging unit 4p, and the entire substrate W can be divided into multiple times. Scan and shoot and check.

Further, a rotary table mechanism may be provided between the slider of the Y-axis stage 82 and the substrate stage 20 as needed. Thereby, the angle of the substrate W can be changed, and the positional deviation of the substrate W can be corrected, or the direction of photographing, inspection, reception, and transfer of the substrate can be changed to 90 degrees, 180 degrees, or 270 degrees.

Further, in the case of applying the present invention, in the above description, a configuration is shown in which the substrate W is continuously moved while the sheet-shaped illumination light is irradiated from the illumination unit 3, and S-polarized light is used. The linear sensor of the imaging unit 4s and the P-polarized imaging unit 4p performs imaging. According to this configuration, since the substrate W can be imaged while continuously moving in the Y direction, the time can be shortened, and no special correction of the optical property is required. Therefore, rapid inspection can be realized.

Since the substrate inspection apparatus 1 of the present invention has such a configuration, it is possible to detect the position and size of the foreign matter adhering to the inspection target region R set on the substrate W, and accurately determine that the foreign matter adheres to the front surface S1 side of the substrate W. Which one of the back side S2 side. In addition, even if the inspection target substrate is thinned, the result obtained by the S-polarized imaging unit 4s and being inspected and the result of the inspection by the P-polarized imaging unit 4p can be compared with the result obtained by the P-polarized imaging unit 4p, and based on the substrate to be inspected. The magnitude relationship of the intensity of the scattered light at the same position is examined by which the foreign matter adhering to the substrate adheres to the front side and the back side of the substrate.

[Lighting and camera angle setting]

In the above, the configuration is such that the angle θ1 of the light 32 irradiated from the illumination unit 3 toward the inspection target region R is 80 degrees ± 5 with respect to the normal line H1 of the first principal surface S1 of the substrate W. The illuminating unit 3, the separated polarizing unit 5, the S-polarized imaging unit 4s, and the P-polarized imaging unit 4p are disposed so that the angle θ2 of the imaging by the imaging camera 42 is within 45 degrees ± 5 degrees.

In general, the scattered light from foreign matter generates a difference in strength and weakness depending on the angle, and the difference between the strong and the weak differs depending on the difference in the particle diameter of the foreign matter. However, it is understood that the present invention can be applied to foreign matter of various particle diameters by setting the angles θ1 and θ2 as described above.

Further, it is also known that the same result can be obtained if the angle formed by the angles θ1 and θ2 (that is, θ1 + θ2) is within 125 degrees ± 10 degrees.

[Another angle setting for illumination and video]

In addition, it is also known that the case where the distribution tendency of the foreign matter is desired or the case where the strictness is not required is high, and the particle size of the foreign matter to be inspected is determined in advance is not limited to the above conditions. The present invention is applied under the conditions shown below.

In other words, the angle θ1 of the light 32 irradiated from the illumination unit 3 toward the inspection target region R in the range of 40 to 85 degrees with respect to the normal line H1 of the first principal surface S1 of the substrate W is 40 to 85 degrees in advance, and by the camera 42 Each of the illumination unit 3, the separation polarization unit 5, the S polarization detection unit 4s, and the P polarization imaging unit 4p is disposed such that the angle θ2 of the imaging is in the range of 0 to 60.

Further, the substrate W is exemplified by the use of an alkali-free glass having a thickness t of 0.3 mm, but the present invention can be applied even to an alkali-free glass having another thickness. Further, even when a film such as ITO (Indium Tin Oxide) or SiO _{2 is} applied to the front surface S1 side or the back surface S2 side of the substrate W, it may be applied as long as it does not affect the intensity of scattered light from foreign matter. this invention.

In addition, the conditions of the angles θ1 and θ2 as described above, or the material and thickness of the substrate W, and other conditions are as long as the foreign matter adhering to the front surface S1 side of the substrate is in the S-polarized state. The intensity of the scattered light is > the intensity of the scattered light in the P-polarized state, and the relationship between the scattered light intensity in the P-polarized state and the intensity of the scattered light in the S-polarized state (prerequisite) is established with respect to the foreign matter adhering to the back surface S2 of the substrate. In the same manner as the above-described determination program, the result obtained by the S-polarized imaging unit 4s and the result of the inspection, and the result obtained by the P-polarized imaging unit 4p and being inspected can be compared with the result of the inspection, and based on the substrate to be inspected. The relationship between the intensity of the scattered light at the same position, if the intensity of the scattered light in the S-polarized state is > the intensity of the scattered light in the P-polarized state, it is determined that the foreign matter adheres to the front side of the substrate, and if the intensity of the scattered light in the P-polarized state is >S The intensity of the scattered light in the polarized state is determined to be that the foreign matter adheres to the back side of the substrate, and the present invention is applied.

[Application in the form of the second aspect]

In the above description, the polarization beam splitter 50 is an example in which the light in the S-polarized state and the light in the P-polarized state are separated by 1:1, and the scattering light intensity in the S-polarized state and the scattering in the P-polarized state. The light intensity is described only in the form of the size comparison (that is, the form of the first aspect).

However, in the production of the polarization beam splitter 50, it is difficult to completely align the S-polarized/P-polarized light. The ground is separated into 1:1 and the deviation occurs. In order to cope with such a situation, the substrate inspecting apparatus of the present invention may be in the form as shown below (that is, in the form of the second aspect).

In other words, the multiplier coefficient may be multiplied by any one of the scattered light intensity in the S-polarized state and the scattered light intensity in the P-polarized state, and then compared by the inspection result comparing unit of the foreign matter inspection unit. Alternatively, each of the scattered light intensity in the S-polarized state and the scattered light intensity in the P-polarized state is multiplied by a different magnification factor, and then compared by the inspection result comparing unit of the foreign matter inspection unit.

Moreover, the foreign matter attachment surface determination unit of the foreign matter inspection unit is

The result of comparison between the inspection result comparison unit of the foreign matter inspection unit by the intensity of the scattered light at the same position on the substrate to be inspected

When the intensity of the scattered light in the S-polarized state ÷P is less than the condition of the scattered light intensity > k (k is a constant), it is determined that the foreign matter adheres to the front side of the substrate to be inspected, and if it is S When the intensity of the scattered light in the polarized state ÷P is less than the condition of the scattered light intensity <k (k is a constant) in the polarized state, it is determined that the foreign matter adheres to the back side of the substrate to be inspected.

In this case, the standard particle is spread on the front surface S1 or the back surface S2 of the substrate W with respect to the magnification factor or the value of the constant k which is the criterion for determination, and the scattered light intensity and the P-polarized state in the S-polarized state are measured. The scattered light intensity or the like is set in advance in the foreign matter inspection unit after being grasped in advance.

Therefore, even if the conditions other than the magnitude of the scattered light intensity shown in the form of the first aspect are compared, the result obtained by the S-polarized image capturing unit 4s and inspected can be compared with the P-polarized imaging unit. 4p was taken and the result obtained was examined, and the size of the scattered light intensity at the same position on the substrate to be inspected was examined, and the foreign matter adhering to the substrate was attached to the front side and the back side by the back. As a result, the present invention can be applied to substrates of various materials or thicknesses.

[variation]

In the above, the configuration includes a relative moving unit 8 that causes the illumination unit 3, the separation polarization unit 5, the S polarization imaging unit 4s, and the P polarization imaging unit 4p to be aligned with the substrate W to be inspected. The S-polarized imaging unit 4s and the P-polarized imaging unit 4p are provided with a linear sensor having a specific length in a direction orthogonal to the direction in which the lens is relatively moved, and the illumination unit 3 is configured to move relative to each other. The sheet-shaped illumination light is irradiated to the inspection target area photographed by the line sensor.

According to this configuration, it is possible to perform inspection using a linear sensor having a high resolution, and it is possible to minimize the irradiation range of the illumination light, and thus it is easy to achieve cost reduction or size reduction. Further, it is possible to prevent other foreign matter from being present on the same surface (the first main surface if the first main surface is inspected) or the opposite side (the second main surface if the first main surface is inspected) The scattered light does not correctly obtain the desired inspection result, so it is a better form.

However, the present invention is not limited to this embodiment, and may be configured as described below. In other words, the surface sensor is used for the S-polarized image capturing unit 4s and the P-polarized image capturing unit 4p, and the illuminating unit 3 illuminates the range of the region including the inspection target region captured by the surface sensor. In this case, the relative movement unit 8 is configured to relatively move the illumination unit 3, the S-polarized imaging unit 4s, and the P-polarized imaging unit 4p with respect to the substrate W to be inspected. The S-polarized imaging unit 4s and the P-polarized imaging unit 4p are relatively moved while the illumination device emits illumination light, and the imaging is repeated (that is, the divided imaging is performed).

Alternatively, the substrate W may be moved and stopped in a step-and-repeat manner with respect to the moving portion 8, and the illumination portion may be provided with surface illumination, and the imaging unit may be provided with a surface sensor, which is intermittently set to The inspection target region R of the substrate W is divided and imaged.

Alternatively, the configuration may be such that the relative movement unit 8 is not provided and the surface sensing is used. The camera photographs the inspection target area R at one time.

Further, when the image is captured by the step-and-repeat method or the single image capturing method, the separation polarizing unit 5, the S-polarized image capturing unit 4s, and the P-polarized image capturing unit 4p are aligned with respect to the setting on the substrate W at a specific angle θ2. Since the normal line H1 of the target region R is inclined, it is only necessary to correct the image captured on the trapezoidal shape to a rectangular shape or to use a skew correction lens for imaging.

In addition, it is possible to adopt a configuration in which the imaging is performed as described above, and the entire surface of the substrate W is set as the inspection target region R, and the illumination is applied to the inspection target region R at a time. The light illumination unit and the imaging unit including the surface sensor camera and the lens that captures the inspection target region R are imaged at one time.

Further, the relative moving portion 8 is not limited to the above-described configuration, and may be configured to convey the substrate W using a rotating roller (that is, convey the belt) or to be transported using a walking beam and a holding portion. (ie shuttle transfer), etc.

[variation]

In the above description, the configuration in which the polarization beam splitter 50 is provided as the separation polarizing unit 5 is exemplified. According to this configuration, it is possible to efficiently separate the incident scattered light into the S-polarized state and the P-polarized state. Therefore, when the intensity of the illumination light cannot be made strong or the intensity of the scattered light is weak, it is preferable. . However, when the intensity of the illumination light is strong or the intensity of the scattered light is strong, the separation of the present invention can be constituted not only by such a configuration but also by the following configuration. Polarized section.

Fig. 7 is a perspective view showing another example of the embodiment of the present invention.

Fig. 8 is a view showing, in combination, a main part of another example for realizing the embodiment of the present invention and a captured scattered light intensity.

In Figs. 7 and 8, the separation polarizing portion 5B having a configuration different from that of the separation polarizing portion 5 shown in Figs. 1 and 2 is shown.

The separation polarizing unit 5B includes a half mirror 50B, an S polarizing filter 54s, and a P polarizing filter 54p.

The half mirror 50B bends one of the portions 51b, 52b of the incident light 51a, 52a by 90 degrees, and passes the portions 51c, 52c straight through. Here, a description will be given of a configuration in which one half of the incident light is bent and reflected, and the other half is passed straight (that is, the incident light is separated into 1:1).

One of the separated lights (here, the bending reflection sides) 51b, 52b passes through the S polarizing filter, and the other (here, the straight passing side) 51c, 52c passes through the P polarizing filter. The S-polarized filter transmits light of the S-polarized component efficiently, and efficiently absorbs or reflects the light of the P-polarized component. On the other hand, the P-polarized filter transmits light of the P-polarized component efficiently, and efficiently absorbs or reflects the light of the S-polarized component.

The light 51s' and 52s' passing through the S-polarized filter are respectively imaged by the S-polarized imaging unit 4s, and the light 51p' and 52p' of the P-polarized filter are respectively captured by the P-polarized imaging unit 4p. The subsequent inspection flow is the same as described above, and thus the description is omitted.

Furthermore, when the intensity of the illumination light 32 is strong or when the intensity of the scattered light is large, such as when the intensity of the scattered light is relatively strong, even if it is separated by a half mirror (that is, the amount of light is attenuated to half) After that, the intensity of the light passing through the S-polarized or P-polarized filter can also be ensured, so that the correct inspection can be performed.

[variation]

In the above description, the light source unit of the illumination unit is configured to include a xenon lamp or the like. However, the present invention is not limited to such a configuration, and may be configured to include other light source devices. As the light source device of the illumination unit, for example, a fluorescent lamp, an LED, a semiconductor laser oscillator, or the like can be exemplified. More preferably, the illumination unit includes a semiconductor laser oscillator, and the illumination light that is emitted from the illumination unit toward the inspection target region is light that is excited by the semiconductor laser oscillator.

The light system excited by the semiconductor laser oscillator has less deviation in wavelength or amplitude than the other light source devices and has the same phase, that is, the same dimming. Therefore, the phase plate can be easily used to adjust the polarization direction.

For example, when the illumination light from the illumination unit including the semiconductor laser oscillator is linearly polarized in the X direction, it is converted into circularly polarized light and is irradiated toward the inspection target region. Alternatively, the linearly polarized light in a state in which the light advance direction is a rotation center from the horizontal direction of the X direction by 45 degrees (that is, a state in which the S polarized light and the P polarized light are 1:1) is irradiated toward the inspection target region. The linearly polarized light in a state of being rotated by 45 degrees can be disposed in a state where the semiconductor laser oscillator is rotated by 45 degrees, or can be realized by using a phase plate.

Further, it is not limited to the configuration using one semiconductor laser oscillator, and two semiconductor laser oscillators having different polarization directions may be used, and the state in which the light of the S-polarized component and the P-polarized component are mixed may be used. Check the target area for illumination.

Further, it is preferable that the illumination light irradiated from the illumination unit including the semiconductor laser oscillator has the same ratio of the S-polarized component and the P-polarized component. In this case, it is possible to compare only the scattered light intensity of the S-polarized state captured by the S-polarized imaging unit and the scattered light intensity of the P-polarized state captured by the P-polarized imaging unit. It is easy to determine which of the first main surface or the second main surface of the substrate the foreign matter adheres to.

However, even if the S-polarized component and the P-polarized component of the illumination light irradiated from the illumination unit including the semiconductor laser oscillator are not at the same ratio, the intensity of the scattered light in the S-polarized state captured by the S-polarized imaging unit can be At least one of the scattered light intensities of the P-polarized state captured by the P-polarized imaging unit is multiplied by a magnification factor and compared, and based on the magnitude relationship, it is easy to determine that the foreign matter adheres to the first main surface or the second surface of the substrate. Which of the main faces?

[variation]

In the above, as shown in FIGS. 1, 2, 7, and 8, the illumination light 32 that is irradiated toward the inspection target region R from the illumination unit 3 is directly irradiated to the inspection target region R. However, the present invention is not limited to this configuration, and may be configured as shown in FIG.

Fig. 9 is a front elevational view showing the main part of still another example of the embodiment of the present invention.

In Fig. 9, an illumination unit different from the configuration of the illumination unit 3 shown in Figs. 1 and 2 is shown. 3B, light 33 irradiated from the irradiation unit 3B, and the like.

Specifically, the illuminating unit 3B includes a sheet light illumination unit 31 that illuminates the sheet-shaped illumination light 32 downward in a substantially vertical direction, and a mirror 35 disposed below the sheet illumination unit 31. The mirror 35 changes the direction of the sheet-shaped illumination light 32 to illuminate it as the reflected illumination light 36 to the inspection target region R. Then, the illumination light 36 is irradiated onto the inspection target region R of the substrate W, and the scattered light 51a, 52a emitted from the foreign matter X1, X2 is incident on the separation polarizing portion 5.

[variation]

In the above description, the S-polarized imaging unit 4s and the P-polarized imaging unit 4p are provided with individual lenses 43s and 43p. However, the configuration is not limited to this, and a common lens 43 (indicated by a broken line in FIG. 1) may be provided on the incident side of the separation polarizing unit 5 instead of using the individual lenses 43s and 43p.

1‧‧‧Substrate inspection device

2‧‧‧Substrate retention department

3‧‧‧Lighting Department

4p‧‧‧P Polarized Camera

4s‧‧‧S polarized camera

5‧‧‧ Separation of polarized parts

7‧‧‧ Foreign Body Inspection Department

8‧‧‧ Relative Mobile Department

11‧‧‧ device framework

15‧‧‧Connected components

20‧‧‧Substrate mounting table

31‧‧‧Lighting unit

32‧‧‧Lights

33‧‧‧Arrows (light forward)

42p‧‧‧ camera (for P-polarization inspection)

42s‧‧‧ Camera Camera (for S-polarization inspection)

43‧‧‧ lens

43p‧‧‧Lens (for P-polarization inspection)

43s‧‧‧Lens (for S-polarization inspection)

50‧‧‧Polarizing beam splitter

81‧‧‧X-axis platform

82‧‧‧Y-axis platform

R‧‧‧ inspection area

W‧‧‧Substrate

X‧‧‧X axis

Y‧‧‧Y axis

Z‧‧‧Z axis

Claims (8)

A substrate inspection device including: a substrate holding portion that holds a substrate to be inspected; an illumination portion that emits illumination light toward an inspection target region set on the substrate; and a separation polarizing portion that emits from the inspection target region The scattered light is separated into light in a S-polarized state and light in a P-polarized state; an S-polarized imaging unit that captures light in a S-polarized state in which the scattered light is separated; and a P-polarized imaging unit that separates the captured scattered light And a foreign matter inspection unit that checks the front side or the back side of the substrate to be inspected based on the image captured by the S-polarized image capturing unit and the P-polarized image capturing unit; The foreign matter inspection unit includes a foreign matter attachment surface determination unit that compares the result of the image detection by the S-polarization imaging unit and the P-polarization imaging unit. Shooting and checking the obtained result, and determining the foreign matter adhesion according to the magnitude relationship of the scattered light intensity at the same position on the substrate to be inspected Which of the front side or the back side of the substrate to be inspected is the one to be examined. The substrate inspection apparatus according to claim 1, wherein the foreign object inspection unit compares the result obtained by the S-polarized image capturing unit and the result of the inspection, and the result of the inspection by the P-polarized image capturing unit, and the result is a substrate to be inspected. on When the magnitude of the scattered light intensity at the same position is the scattered light intensity in the S-polarized state > the scattered light intensity in the P-polarized state, it is determined that the foreign matter adheres to the front side of the substrate to be inspected, and if it is in the P-polarized state When the intensity of the scattered light is less than the intensity of the scattered light in the S-polarized state, it is determined that the foreign matter adheres to the back side of the substrate to be inspected. The substrate inspection device according to claim 1, wherein the foreign object inspection unit includes a foreign matter attachment surface determination unit that captures and inspects the result obtained by the S polarization detection unit and the P-polarized image. The result of photographing and checking the result is obtained by multiplying at least one by the magnification factor, and the magnitude of the scattered light intensity at the same position on the substrate to be inspected is the scattered light intensity of the S-polarized state ÷P polarized state. When the intensity of the scattered light is > k (k is a constant), it is determined that the foreign matter adheres to the front side of the substrate to be inspected, and if the intensity of the scattered light in the S-polarized state is ÷P, the scattered light intensity of the polarized state is <k (k is In the case of the constant, it is determined that foreign matter adheres to the back side of the substrate to be inspected. The substrate inspection apparatus according to any one of claims 1 to 3, wherein the illumination unit includes a semiconductor laser oscillator, and the illumination light emitted from the illumination unit is light excited by the semiconductor laser oscillator. The substrate inspection device according to claim 4, wherein the S-polarized component and the P-polarized component of the illumination light irradiated from the illumination portion are at the same ratio. The substrate inspection apparatus according to any one of claims 1 to 5, wherein The substrate to be inspected is a transparent glass substrate, and the illumination unit is disposed such that illumination light irradiated from the illumination unit is irradiated at an angle of 40 to 85 degrees with respect to a normal line of the inspection target region, and the imaging is performed. The part is arranged such that the inspection target area is imaged at an angle of 0 to 60 degrees with respect to the normal line of the inspection target area. The substrate inspection apparatus according to any one of claims 1 to 5, wherein the substrate to be inspected is a transparent glass substrate, and the light irradiated toward the inspection target region by the polarizing portion is polarized, and the imaging unit The scattered light of the image is set to be within 125 degrees ± 10 degrees with the normal line of the inspection target region interposed therebetween. The substrate inspection apparatus according to claim 7, wherein the substrate to be inspected is a transparent glass substrate, and the substrate inspection device is configured to emit light directed toward the inspection target region by the polarization of the polarizing portion with respect to the inspection target region. The normal line is arranged to be irradiated at an incident angle of 80 degrees ± 5 degrees, and the imaging unit is disposed such that the inspection target region is imaged at an angle of 45 degrees ± 5 degrees with respect to a normal line of the inspection target region.