JPH11307603A - Inspecting method and device for foreign matters - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently inspect the size and quality of foreign matters. SOLUTION: In a foreign matter inspecting device 10 for inspecting a foreign matter by detecting the scattering beams 31 of inspecting beams 21 for a foreign matter 5, under a dark visual field using oblique irradiation of a wafer 1 in an inspection beam irradiation system 20, a regular reflection beam detector 42 is provided on the regular reflecting position of the inspecting beams 21 of the inspection beam irradiation system 20, while a comparator 43 for comparing mutual output signals on the same positions in different chips is connected to the output terminal of the regular reflection bean detector 42, while a size determining part 44 determines the size of foreign matters by the output signals connected to the comparator 43. Through these procedures, an operator can control the manufacturing process precisely and rapidly by specifying the size, shape, etc., of the foreign matters in addition to the coordinate positions of the same.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foreign matter inspection apparatus, and more particularly to a technique for detecting minute foreign matter on a surface to be inspected with high sensitivity. For example, foreign matter adhered to the surface of a semiconductor wafer (hereinafter, referred to as a wafer). The present invention relates to a technology that is effective for detecting and inspecting a target.

[0002]

2. Description of the Related Art Today, semiconductor integrated circuit devices (hereinafter, ICs)
That. )) And the miniaturization of circuit patterns has progressed, and the line width of the circuit patterns has been reduced to about 1 μm or less. In order to manufacture such ICs at a high yield, foreign substances adhering to the surface of the wafer are detected, their size, shape, physical properties, etc. are inspected, and the cleanliness of various semiconductor manufacturing equipment and processes is quantitatively determined. It is necessary to understand and properly manage the manufacturing process. Therefore, in a conventional IC manufacturing plant, a wafer foreign matter inspection method using a wafer foreign matter inspection apparatus has been implemented for a wafer as a work in order to accurately manage a manufacturing process.

[0003] Conventional wafer foreign matter inspection apparatuses are roughly classified into two.
Into two categories. The first is an image comparison type wafer foreign matter inspection apparatus (hereinafter, referred to as an apparatus) that compares an image in a bright field by vertical epi-illumination with a standard pattern stored in advance.
It is called a visual inspection device. ). Secondly, a wafer foreign matter inspection apparatus (hereinafter referred to as foreign matter inspection apparatus) of a type that detects scattered light in a dark field due to oblique illumination and recognizes presence / absence of foreign matter, position coordinates and number of foreign matter based on coordinates at the time of detecting scattered light. Device).

As an example describing a wafer foreign matter inspection apparatus, there is “Nikkei Micro Devices, March 1997”, pages P97 to P116, issued by Nikkei BP Co., Ltd.

[0005]

The above-described appearance inspection apparatus has the advantage of high inspection accuracy, but has the disadvantage of low throughput and high cost. Since the image data is obtained by the appearance inspection device, the appearance inspection device can execute a so-called review (confirmation or verification work using images). However, the present inventor has clarified that the appearance inspection apparatus has a problem that the number of inspection unnecessary information such as small defects is large in spite of the small number of inspection wafers, so that the critical defect capture rate is low and the review efficiency is extremely low. Was done.

The above-described foreign substance inspection apparatus has a disadvantage that the inspection accuracy is lower than that of the appearance inspection apparatus, but has the advantages that the throughput is higher and the price is lower than the appearance inspection apparatus. Since the data obtained from the foreign matter inspection apparatus is the position coordinates of the foreign matter in the wafer and the intensity of the scattered light, the foreign matter inspection apparatus cannot obtain information on the size (particle size) and shape of the foreign matter. Therefore, in order to obtain such information, it is necessary to use a visual inspection apparatus or a wafer foreign substance analyzer of an analysis system having a long inspection time such as an SEM (scanning electron beam microscope).

It is an object of the present invention to provide a foreign matter inspection technique capable of efficiently inspecting the size and shape of a foreign matter.

The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

[0009]

The outline of a typical invention among the inventions disclosed in the present application is as follows.

That is, a foreign matter inspection method for inspecting foreign matter by obliquely illuminating the object to be inspected by an inspection light irradiation device and detecting scattered light of inspection light in the object to be inspected in a dark field by a scattered light detector. Wherein a specular reflection light detector is provided at a specular reflection position of the inspection light of the scattered light irradiation device, and at least a size of a foreign substance is specified based on an output signal of the specular reflection light detector.

A foreign matter inspection method for inspecting foreign matter by obliquely illuminating the object to be inspected by an inspection light irradiation device and detecting scattered light of inspection light in the object to be inspected in a dark field by a scattered light detector. , Characterized in that at least the properties of the foreign matter are specified by taking in the scattered light and performing Fourier spectrum analysis.

According to the first means, since at least the size of the foreign matter can be recognized, the foreign matter can be efficiently reviewed.

According to the second means, since at least the property of the foreign substance can be recognized, the analysis of the foreign substance can be executed efficiently.

[0014]

FIG. 1 is a perspective view showing a foreign matter inspection apparatus according to one embodiment of the present invention. FIG. 2 is a flowchart showing the foreign matter inspection method. FIG. 3 et seq. Are explanatory diagrams for explaining the operation.

In the present embodiment, the foreign matter inspection apparatus according to the present invention detects scattered light in a dark field by oblique illumination on a wafer to be inspected, and detects presence or absence of foreign matter based on coordinates at the time of detecting the scattered light. The inspection apparatus 10 is configured as a foreign substance inspection apparatus 10 of a type that recognizes the position and the position coordinates and the number. A wafer 1 to be inspected has a first main surface 2 on which DR, which is an example of an IC, is provided.
AM is being manufactured for each chip portion 4, and the chip portions 4 are arranged regularly and horizontally and vertically with respect to an orientation flat (hereinafter, referred to as an orientation flat) 3 cut out on the wafer 1. Foreign matter 5 on first main surface 2 of wafer 1
If foreign matter adheres to the first main surface 2 of the wafer 1, the foreign matter 5 is detected by the foreign matter inspection device 10, and the position, number, size, shape,
Inspection of color and properties, quantitatively grasping the cleanliness of various semiconductor manufacturing equipment and processes, and appropriately managing the manufacturing process are performed. In the present embodiment, the position and the number, the size and the shape of the foreign matter are inspected.

The foreign matter inspection apparatus 10 includes a stage device 11, which includes an XY table 12 for scanning the wafer 1 as an object to be inspected, a θ table 13 for rotating in the θ direction, and an automatic focusing device. An alignment mechanism (not shown) and a controller 14 for controlling these mechanisms are provided. Then, in order to inspect the entire surface of the wafer 1, the stage apparatus 11 performs XY scanning of the wafer 1. During this scanning, the coordinate position information on the wafer 1 as the object to be inspected is sequentially input from the controller 14 to a foreign matter determination device described later.

An inspection light irradiation device 20 is provided diagonally above the stage device 11. The inspection light irradiation device 20 includes a laser light irradiation device 22 that irradiates the wafer 1 with laser light 21 as inspection light, and a condenser lens 23 that collects the laser light 21. By irradiating the wafer 1 as an object to be inspected held on the stage device 11 at a low angle, the wafer 1 is obliquely illuminated.

A scattered light detection device 30 is provided directly above the stage device 11. This scattered light detection device 30
The scattered light 31 irregularly reflected on the surface of the wafer 1 as the laser light 21 is obliquely irradiated on the surface of the wafer 1
Lens 32 for condensing light, a relay lens 33 for forming an image of the scattered light 31 condensed by the objective lens 32 on the light receiving surface of the scattered light detector 35, and a spatial filter for transmitting only a predetermined component of the scattered light 31 34, and a scattered light detector 35 for detecting the scattered light 31. That is, the scattered light detection device 30 is configured to detect the scattered light 31 in a dark field. In the present embodiment, the scattered light detector 35 is configured by a line sensor in which solid-state imaging photoelectric conversion elements are arranged in a slender manner, and is arranged to be longer in the Y direction orthogonal to the stage moving direction.

A foreign matter determination device 36 is connected to the scattered light detector 35, and the foreign matter determination device 36 determines the presence or absence of foreign matter on the wafer 1 based on the detection time point of the scattered light from the scattered light detector 35. At the same time, by comparing the determined data with the coordinate position data from the controller 14 of the stage device 11, the coordinate position of the foreign matter is specified. The scattered light detector 35 also transmits the scattered light intensity to the foreign matter determination device 36.

At the regular reflection position of the laser beam irradiation device 22 above the stage device 11, a foreign matter size specifying device 40 is provided.
The foreign matter size specifying device 40 is provided with a regular reflection light detector 42 for detecting the regular reflection light 41. The regular reflection light detector 42 is configured by a line sensor in which solid-state imaging photoelectric conversion elements are arranged in a slender manner, and is arranged so as to be longer in the X direction which is the stage moving direction.
One input terminal of the comparison unit 43 is connected to the output terminal of the regular reflection light detector 42, and the input terminal of the foreign matter size determination unit 44 is connected to the output terminal of the comparison unit 43. One input terminal of the verification unit 45 is connected to an output terminal of the foreign substance size determination unit 44, and a classification unit 46 is connected to one output terminal of the verification unit 45. A foreign matter determination device 36 is connected to another input terminal of the comparison unit 43 and another input terminal of the verification unit 45. The foreign matter determination device 36 includes a host computer 37 that controls the foreign matter inspection device 10, the comparison unit 43, and the verification unit 43. The determination result is transmitted to the unit 45.

Next, a foreign substance inspection method according to an embodiment of the present invention using the foreign substance inspection apparatus 10 having the above-described configuration will be described with reference to FIG.

When the inspection light irradiating device 20 irradiates the wafer 1 with the laser light 21 as inspection light at a low inclination angle, the irradiation of the laser light 21 causes foreign matter adhered to the first main surface 2 of the wafer 1. 5 and a circuit pattern generate scattered light 31 in a dark field (see FIG. 3). This scattered light 31
Is condensed by the objective lens 32 and is imaged on the scattered light detector 35 through the relay lens 33.

At this time, the scattered light 31 from the circuit pattern
Has regularity, so that the scattered light 31 from the circuit pattern can be shielded by the spatial filter 34. On the other hand,
Since the scattered light 31 from the foreign matter 5 is irregular, the scattered light 31 passes through the spatial filter 34 and forms an image on the scattered light detector 35. Therefore, only the foreign matter 5 can be detected.

A detection signal based on the scattered light 31 in the dark field from the foreign substance 5 detected by the scattered light detector 35 is input to the foreign substance determination device 36. Foreign matter determination device 36
Determines the presence / absence of the foreign matter 5 based on the detection signal, and specifies the coordinate position of the foreign matter 5 by comparing the determination data with the coordinate position data from the controller 14 of the stage device 11. The coordinate position of the foreign matter 5 specified in this way is output from the foreign matter determination device 36 to, for example, a host computer 37 that comprehensively executes the foreign matter inspection device 10, and the size determination unit 44 of the foreign matter size specification device 40 Sent to. Incidentally, the foreign matter determination device 36 temporarily stores data for at least one chip.

When the scattered light 31 is generated as shown in FIG. 3A by irradiating the foreign matter 5 with the laser light 21, the incident light of the regular reflection light 41 to the regular reflection light detector 42 is changed. Since it disappears or decreases, the output signal of the regular reflection light detector 42 changes irregularly as shown in FIG. By the way, as shown in FIG. 3C, when there is no foreign matter on the wafer 1, the laser beam 21 is regularly reflected by the circuit pattern 6, so that the regular reflection light detector 42
Output signal is in a state of maintaining regularity as shown in FIG.

With the movement of the wafer 1 in the X direction by the scanning of the stage device 11, the regular reflection light 41 of the laser light 21 from the wafer 1 continuously enters the regular reflection light detector 42. The reflected light detector 42 compares the detection signal with the comparing unit 43.
Output continuously. Normally, the regular reflection light detector 42 compares the regular detection signal shown in FIG.
Output to However, when the scattered light 31 is generated by irradiating the foreign matter 5 with the laser light 21, the output signal of the regular reflection light detector 42 changes irregularly as shown in FIG.

When the detection signal of the foreign matter 5 is sent from the foreign matter determination device 36 to the comparison section 43, the comparison section 43 outputs the output signal of the regular reflection light detector 42 at the time of transmission of the detection signal and the foreign matter 5 Are compared with the output signals from the specularly-reflected light detector 42 at a position separated by one chip interval from the coordinate position. That is, the comparing section 43 delays the output signal 42b including the foreign substance 5 shown in FIG. 3B by one chip by the detection signal from the foreign substance determination device 36, and outputs the output signal 42b and the output signal 42b shown in FIG. As shown in FIG. 3E, the output signal 42d not including the foreign matter 5 from the specular reflection light detector 42 at a position separated by the distance of one chip shown in FIG. .

In FIG. 3E, the change component signal 43e
Corresponds to the size of the foreign substance 5 in the X direction. Since the time t on the horizontal axis is proportional to the scanning speed of the stage device 11 in the X direction, the size of the foreign matter 5 can be determined by measuring the time of the change component signal 43e. Incidentally, the comparing section 43 temporarily stores the output signal of at least one chip. Therefore, the comparing unit 43 detects the foreign matter 5
Not only the size in the X direction but also the size in the Y direction can be measured.

Then, the comparing section 43 outputs the change component signal 43e.
Is transmitted to the foreign matter size determination unit 44. The foreign matter size determination unit 44 determines the size of the foreign matter 5 by measuring the time of the change component signal 43e. Foreign matter size determination unit 44
Transmits the determined size of the foreign substance 5 to the verification unit 45.

When a signal indicating the size of the coordinate position of the foreign matter 5 transmitted from the foreign matter determination device 36 is transmitted from the foreign matter size determination unit 44, the verification unit 45 determines that the foreign matter determination device 36 has a foreign matter. The judgment verifies that it is appropriate. On the other hand, when the signal is not transmitted from the foreign substance size determination unit 44 for the coordinate position of the foreign substance 5 transmitted from the foreign substance determination device 36, the verification unit 45
Recognizes that the determination of presence of foreign matter by the foreign matter determination device 36 is erroneous. If it is determined that the determination is erroneous, the verification unit 45
Transmits this to the host computer 37.

The size of the verified foreign material 5 is determined by the classification unit 46.
Is forwarded to The classification unit 46 classifies the size and shape of the foreign matter 5 according to a preset algorithm. For example, as shown in FIG. 4A, the vertical a and horizontal b dimensions of the foreign matter are specified. The area of the foreign matter 5 is specified as shown in FIG. 4B by the product (a × b) of the vertical a and the horizontal b of the foreign matter 5. The shape of the foreign matter 5 is specified by the quotient (a / b) of the vertical a and the horizontal b of the foreign matter 5. For example, when a / b = 1, the foreign matter 5 is specified as having a circular shape as shown in FIG. a / b
> 1 or a / b <1, the foreign matter 5
It is specified as having an elongated shape as shown in (d).

The classification result of the foreign matter 5 classified as described above is transmitted from the classification unit 46 to the host computer 37. The host computer 37 uses the classification data from the classification unit 46 and the coordinate position data and the number data of the foreign substance 5 from the foreign substance determination device 36 to appropriately create various analysis data shown in FIG. And output it in a timely manner by an output device such as a printer. The operator can accurately and quickly manage the IC manufacturing process based on the output various analysis data.

FIG. 5A is a map for each foreign matter size.
It is created based on the foreign matter size data and the coordinate position data of the foreign matter. FIG. 5B is a histogram for each foreign substance size. The horizontal axis represents the foreign substance size as a variable divided into sections, and the vertical axis represents the number of detected values as the number of measurement values belonging to each foreign substance size.

FIG. 5C shows a foreign matter shape-specific map, which is created from foreign matter shape data and coordinate position data of the foreign matter. FIG. 5D is a histogram for each foreign matter shape. The horizontal axis represents the foreign matter shape as a variable divided into sections, and the vertical axis represents the number of detected values as the number of measurement values belonging to each foreign matter shape.

FIG. 5E is an inspection result time-series transition graph, which is created based on the inspection date, foreign matter size data, foreign matter shape data (for example, elongated), and organic matter data as an example of foreign matter properties. In addition, not only the time series but also a lot number, a wafer number, and the like may be used.

According to the above embodiment, the following effects can be obtained.

By using specular reflection light to specify the size and shape of the foreign matter whose coordinate position has been identified by the foreign matter inspection device, the operator can accurately and quickly manage the IC manufacturing process. Therefore, the production yield of IC can be improved.

When specifying the size of the foreign matter based on the specular reflection light detection signal from the specular reflection light detector, the specular reflection light detection is performed by comparing the specular reflection light detection signals at the same position between chips at different positions. Since the noise included in the signal can be canceled, the size of the foreign matter can be accurately specified.

By verifying the determination of the foreign matter determination unit based on the scattered light detector by the foreign matter size specifying device,
Since the inspection accuracy of the foreign matter inspection device can be improved, the quality and reliability of the foreign matter inspection device can be improved in combination with the above.

Since the size and shape of the foreign matter can be specified in addition to the coordinate position of the foreign matter without using a visual inspection device that requires a long inspection time or an extremely expensive foreign matter analyzer, a unit area (one wafer) Per) inspection time and review time can be greatly reduced. As a result, the lot inspection can be implemented, and the operator can accurately and quickly manage the IC manufacturing process.

FIG. 6 is a perspective view showing a foreign substance inspection apparatus according to the second embodiment of the present invention. FIG. 7 is a flowchart showing the foreign substance inspection method.

The foreign substance inspection apparatus 10A according to the second embodiment differs from the foreign substance inspection apparatus 10 according to the first embodiment in that:
The configuration is such that the properties of the foreign matter can be specified. That is, the foreign matter property specifying device 50 is provided in the middle of the scattered light detection device 30 above the stage device 11. The foreign matter property identification device 50 is the scattered light detection device 30
A half mirror 51 for optically deriving a part of the scattered light 31 and a scattered light 31 which is installed optically behind the half mirror 51 to take in the scattered light 31 and perform a Fourier spectrum analysis process on the scattered light 31 to thereby remove foreign matter. And a foreign matter property determining unit 52 for determining the properties of the foreign matter. The foreign matter determination device 36 is connected to another input terminal of the foreign matter property determination unit 52.

Next, the foreign substance inspection apparatus 10A according to the above configuration
A foreign matter inspection method according to an embodiment of the present invention will be described with reference to FIG.

Here, it is known that the Fourier spectrum of the scattered light 31 scattered from the foreign matter 5 differs depending on the property of the foreign matter 5, and the property of the foreign matter 5 can be determined by analyzing the Fourier spectrum. Therefore,
When a detection signal of the foreign matter 5 is sent from the foreign matter determination device 36 to the foreign matter property determination unit 52, the foreign matter property determination unit 52 performs a Fourier spectrum analysis on the scattered light 31 captured through the half mirror 51. Then, the properties of the foreign matter 5 are determined. The foreign matter property determination unit 52 transmits the result of the determination to the host computer 37.

According to this embodiment described above, the properties of the foreign matter whose coordinate position has been identified by the foreign matter inspection apparatus can be specified by using Fourier spectrum analysis. Can be managed accurately and quickly, and the production yield of ICs can be increased.

FIG. 8 is a perspective view showing a foreign substance inspection apparatus according to Embodiment 3 of the present invention.

This embodiment is a combination of the first embodiment and the second embodiment.
And a foreign matter property specifying device 50 are mounted. The functions and effects of the foreign matter inspection method according to the present embodiment are the same as those of the first and second embodiments, and thus detailed description will be given to the first embodiment.

Although the invention made by the inventor has been specifically described based on the embodiment, the invention is not limited to the embodiment, and various modifications can be made without departing from the gist of the invention. Needless to say.

For example, the specification of the position of the foreign matter by detecting the scattered light in the dark field is not limited to the configuration using the light shielding element, and the configuration is also performed by comparing the detection data at the same position in the repeated pattern. May be. In this case, the data for comparison may be detection data of an adjacent chip, or may be design pattern data or standard pattern data stored in advance.

In the example in which the line sensor is used, the image pickup device is not limited to the line sensor, but may be an area sensor or an image pickup tube.

In the above description, the case where the invention made by the present inventor is mainly applied to the foreign matter inspection technology of a wafer, which is the background of the application, has been described. However, the present invention is not limited to this. The present invention can be applied to a general foreign matter inspection technique for a plate-like object such as a panel.

[0052]

The effects obtained by typical aspects of the invention disclosed in the present application will be briefly described as follows.

By specifying the size, shape, and properties of the foreign matter in addition to the coordinate position of the foreign matter using the foreign matter inspection device, the worker can accurately and quickly manage the manufacturing process, thereby increasing the manufacturing yield. it can.

Since the size, shape, and properties of the foreign matter can be specified in addition to the coordinate position of the foreign matter without using a visual inspection device or a foreign matter analyzer which requires a long inspection time, the unit area (per wafer) ) Inspection time and review time can be significantly reduced. as a result,
Not only the lot inspection can be realized, but also the operator can manage the manufacturing process accurately and quickly.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a foreign matter inspection apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a foreign matter inspection method.

FIGS. 3A and 3B show a specific action of a foreign matter size, wherein FIG. 3A is an explanatory view showing scattered light of the foreign matter, FIG. 3B is a waveform chart showing an output signal of a regular reflection light detector when scattered light is generated, FIG. 3C is an explanatory diagram showing specular reflected light, FIG. 4D is a waveform diagram showing an output signal of a regular reflected light detector when regular reflected light is generated, and FIG. 4E is a waveform diagram showing an output signal of a comparison unit.

FIGS. 4A and 4B are explanatory diagrams showing a classifying action, wherein FIG. 4A shows a function for specifying the vertical and horizontal dimensions of a foreign substance, FIG. 4B shows a function for specifying a foreign substance size, FIG. 4C shows a specific function for a circular foreign substance, and FIG. Indicates the specific action of the elongated foreign matter, respectively.

FIGS. 5A and 5B are explanatory diagrams showing various analysis data, wherein FIG. 5A is a map for each foreign substance size, FIG. 5B is a histogram for each foreign substance size, FIG. 5C is a map for each foreign substance shape, and FIG. , (E) are test result time series transition graphs.

FIG. 6 is a perspective view showing a foreign substance inspection device according to a second embodiment of the present invention.

FIG. 7 is a flowchart showing a foreign matter inspection method.

FIG. 8 is a perspective view showing a foreign substance inspection device according to a third embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Wafer (inspection object), 2 ... 1st main surface, 3 ... Ori-flat, 4 ... Chip part, 5 ... Foreign matter, 6 ... Circuit pattern, 1
0, 10A, 10B: Foreign matter inspection device, 11: Stage device, 12: XY table, 13: θ table, 14: Controller, 20: Inspection light irradiation device, 21: Laser light (inspection light), 22: Laser light irradiation Device, 23: condenser lens, 30: scattered light detector, 31: scattered light, 32: objective lens, 33: relay lens, 34: spatial filter, 3
5: Scattered light detector, 36: Foreign matter determination device, 37: Host computer, 40: Foreign matter size specifying device, 41: Regular reflection light, 42: Regular reflection light detector, 42b, 42d: Output signal, 43: Comparison unit Reference numeral 43e: change component signal; 44, foreign matter size determination unit; 45, verification unit; 46, classification unit; 50, foreign matter property specifying device; 51, half mirror; 52, foreign matter property determination unit.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masami Ikoda 6-16-16 Shinmachi, Ome-shi, Tokyo 3 Inside the Device Development Center, Hitachi, Ltd. (72) Inventor Yuko Inoue 3--16 Higashi-Higashi, Shibuya-ku, Tokyo 3 Hitachi Electronics Engineering Co., Ltd. (72) Inventor Tetsuya Watanabe 3-16-3 Higashi, Shibuya-ku, Tokyo Inside Hitachi Electronics Engineering Co., Ltd.

Claims (10)

[Claims] 1. A foreign matter inspection method for inspecting foreign matter by obliquely illuminating an inspection object by an inspection light irradiation device and detecting scattered light of inspection light in the inspection object in a dark field by a scattered light detector. In the foreign matter inspection method, a regular reflection light detector is provided at a regular reflection position of the inspection light of the scattered light irradiation device, and at least a size of the foreign matter is specified based on an output signal of the regular reflection light detector. . 2. The method according to claim 1, wherein, when specifying at least the size of the foreign matter based on the output signal of the specular reflection light detector, the output signals at the same position on different chips are compared. Foreign matter inspection method. 3. A method according to claim 1, wherein the presence or absence of a size signal of the foreign matter specified based on the output signal of the specular reflection light detector verifies the suitability for specifying the coordinate position of the foreign matter based on the detection of the scattered light detector. The foreign matter inspection method according to claim 1 or 2, wherein 4. A foreign matter inspection apparatus for inspecting foreign matter by obliquely illuminating the object to be inspected by an inspection light irradiation device and detecting scattered light of inspection light in the object to be inspected in a dark field by a scattered light detector. In the above, a regular reflection light detector is provided at a regular reflection position of the inspection light of the scattered light irradiation device, and is configured to specify at least a size of a foreign substance based on an output signal of the regular reflection light detector. Foreign matter inspection device characterized by the above-mentioned. 5. The output signal of the same position of a different chip is compared with each other when specifying at least the size of a foreign substance based on an output signal of the specular reflection light detector. Foreign matter inspection device. 6. A method according to claim 1, wherein the presence or absence of a size signal of the foreign matter specified based on the output signal of the specular reflection light detector verifies the suitability for specifying the coordinate position of the foreign matter based on the detection of the scattered light detector. The foreign matter inspection device according to claim 4, wherein the inspection device is configured. 7. A foreign matter inspection method for inspecting foreign matter by obliquely illuminating an inspection object by an inspection light irradiation device and detecting scattered light of inspection light in the inspection object in a dark field by a scattered light detector. 3. The foreign matter inspection method according to claim 1, wherein at least the properties of the foreign matter are specified by taking in the scattered light and performing Fourier spectrum analysis. 8. A foreign matter inspection device for inspecting foreign matter by obliquely illuminating the inspection object by an inspection light irradiation device and detecting scattered light of inspection light in the inspection object in a dark field by a scattered light detector. 3. The foreign matter inspection apparatus according to claim 1, further comprising a Fourier spectrum analyzing apparatus for identifying at least the properties of the foreign matter by taking in the scattered light and performing Fourier spectrum analysis. 9. The foreign matter inspection apparatus according to claim 8, wherein the scattered light is taken into the Fourier spectrum analyzer by a half mirror provided on an optical axis of the scattered light detector. 10. The foreign matter inspection device according to claim 8, wherein a regular reflection light detector is provided at a regular reflection position of the inspection light of the scattered light irradiation device, and based on an output signal of the regular reflection light detector. A foreign substance inspection device configured to specify at least the size of a foreign substance.