JP2000216208A - Appearance inspection method and apparatus, and semiconductor device manufacturing method - Google Patents

Abstract

[PROBLEMS] To realize high-throughput discrimination between particles and COP (pseudo particles) in the appearance inspection of a semiconductor wafer. SOLUTION: A plurality of measuring lasers 3 and 4 are provided on a wafer 1 at an incident angle θ1 (of particles and COPs) having different detection sensitivities (light generation amounts of reflected / scattered light A and B) for each of COP and particles. The scanning is performed while alternately irradiating in a pulse shape at the incident angle θ2 (detecting only the particles) and the incident angle θ2, and the photodetector 15 and the determination unit 1 are detected.
In 2, the defect detected by both of the measurement lasers 3 and 4 is determined as a particle from the combination of the respective detection results, and the defect detected by the measurement laser 3 and not detected by the measurement laser 4 is determined to be COP. By doing so, the appearance inspection is performed while discriminating whether the detected defect is a particle such as an attached foreign substance or a COP such as a pit formed on the surface of the wafer 1 by one scan.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a visual inspection technique and a semiconductor device manufacturing technique, and more particularly to a technique which is effective when applied to a visual inspection step for inspecting a surface condition of a semiconductor wafer or the like.

[0002]

2. Description of the Related Art For example, a Si CZ crystal wafer is
When washed with C-1 (a mixture of ammonia and hydrogen peroxide solution), etc., fine pits (dents) counted by a surface defect measuring instrument as if particles exist in a size of 0.1 to 0.2 μm. Is known to appear. In a normal light scattering system as described below, such pseudo particles which cannot be distinguished from real particles (particles) such as adhered foreign substances are CO 2
P (Crystal Originated Part)
icle).

[0003] Currently used wafer appearance inspection apparatuses mainly include one Ar or He-Ne laser,
A laser is irradiated to the wafer from the direction, the scattered light of the wafer is detected by a detector, and the scattered light of the particles and pits adhering to the wafer is separated from the scattered light of the wafer, so that the particles and pits adhering to the wafer are separated. It has a structure that quantifies the size and number.

As devices utilizing this technology, there are a laser surface inspection device LS-6500 manufactured by Hitachi Electronics Co., Ltd. and ADE Optical Systems Corpo.
Wafer Inspection
Many similar devices exist, including the Systems WIS-CR82.

[0005]

The conventional method of irradiating a wafer with a laser from one direction has a technical problem that both particles and pits are detected and cannot be distinguished from each other. As a method to solve this technical problem, after irradiating the laser irradiation angle in the vertical direction and measuring the entire surface, setting the irradiation angle to bevel, again measuring the entire surface, irradiating from the vertical direction and irradiating from the oblique direction A technique for separating particles and pits such as COPs from the difference between the results has been established. As an apparatus having a function capable of changing the laser irradiation angle, there is LS-6500 manufactured by Hitachi Electronics Co., Ltd. or the like.

However, since the LS-6500 and the like have only one laser oscillator, particles and COP
In order to separate the pits, etc., the same wafer must be measured twice with different irradiation angles, and the time required for the appearance inspection process becomes longer than necessary and the other technical problem that the throughput decreases. Will happen.

In the semiconductor device manufacturing process, the appearance of the wafer must be inspected everywhere. Therefore, a decrease in the throughput of the appearance inspection process greatly affects the throughput of the entire semiconductor device manufacturing process.

An object of the present invention is to provide a visual inspection technique capable of distinguishing and detecting different kinds of defects of an object by one measurement.

Another object of the present invention is to provide a visual inspection technique capable of improving the throughput in the visual inspection step.

Another object of the present invention is to provide a semiconductor device manufacturing technique capable of improving a yield and a throughput in a semiconductor device manufacturing process.

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.

[0012]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows.

According to the visual inspection technique of the present invention, when at least two first and second lasers are irradiated on the surface of the object, the light is generated from each of the first and second laser irradiation sites of the object. By detecting the magnitude of the amount of scattered light, the type of defect existing on the surface of the object is discriminated.

More specifically, it is characterized by having the following structure as an example. That is, two oscillators are provided as measurement lasers, and the wafer is irradiated with lasers at different irradiation angles. One of the oscillators has an irradiation angle set substantially perpendicular to the wafer, and irradiates a laser from an angle at which scattered light is generated by both particles and pits such as COPs. The other oscillator is set at an inclined irradiation angle with respect to the wafer, and the laser emitted from the inclined oscillator is installed so that scattered light is less in pits such as a COP than in a laser irradiated from the vertical direction. .

Further, the lasers to be irradiated are all pulse oscillations, and the laser oscillation timing is shifted so that the other laser does not oscillate while one laser is irradiating the wafer. The laser irradiation area irradiates the area irradiated by the laser oscillated first, and the laser irradiation area irradiates the area advanced by the time when the oscillation timing is shifted in the wafer scanning direction. And this is repeated alternately.

That is, assuming that the time of the deviation of the oscillation timing is Δt, the scan speed of the wafer is v, and the area S1 irradiated by one laser, the irradiated laser is OF
F, the area S2 irradiated with the other laser is
The region S1 is set at a position moved by Δt at the scan speed v from the region S1, and the laser irradiation on the region S1 and the region S2 is alternately repeated by two lasers.

The difference in the number of detections when the same location is measured by a laser whose irradiation angle has been changed is determined. The number of particles having a small number of detections in both results is the number of particles, and the difference between the number of large and small results is detected as the number of pits such as COPs.

Thus, in the present invention, by measuring the wafer once, particles adhering to the wafer and COP are measured.
Pits can be separated.

Further, a method of manufacturing a semiconductor device according to the present invention
The above-described visual inspection technique is applied to visual inspection of a semiconductor wafer. As a result, the inspection accuracy of defects such as adhered foreign substances and COPs in the appearance inspection of the semiconductor wafer is improved, the yield is prevented from lowering due to these defects, the yield is improved, and the time required for the appearance inspection is shortened. An improvement in throughput in a semiconductor device manufacturing process is achieved.

[0020]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a conceptual diagram showing an example of the configuration of a visual inspection apparatus for performing a visual inspection method according to an embodiment of the present invention.

The wafer 1 to be measured is placed on a stage 2, and this stage 2 is supported by a rotary motor 2a and a linear motor 2b, and the table driver 16 synchronizes the rotary motor 2a and the linear motor 2b. By performing the control, it is possible to perform a displacement in which the rotational movement by the rotary motor 2a and the linear movement by the linear motor 2b are combined, and the surface of the wafer 1 is spirally scanned by a measuring laser described later. I do.

Above the stage 2, two laser light sources 13 and 14 controlled by the oscillation timing control unit 11 and having different incident angles θ1 and θ2 with respect to the surface of the wafer 1 on the stage 2 are provided. And a measuring laser 3 (measuring laser a) for detecting pits such as particles and COPs, and a measuring laser 4 for detecting particles from two different directions with respect to the wafer 1. (Measurement laser b).

The photodetector 1 is located above the stage 2.
5 for measuring a laser a on the wafer 1
And reflected / scattered light A generated from an irradiated portion of the measurement laser b and composed of at least one of reflected light and scattered light
And reflected / scattered light B are detected. The light amounts of the reflected / scattered light A and the reflected / scattered light B detected by the photodetector 15 are compared with different predetermined thresholds by the determination unit 12, and the presence or absence of particles or pits is determined. The result is input to the main control unit 10 that controls the whole, and is recorded in the inspection result table 20 of the storage device 10a as necessary.

In the example of FIG. 1, one photodetector 15
Is commonly used for detecting the reflected / scattered light A and B of the measuring lasers a and b. However, a plurality of photodetectors 15 are provided at different positions to separate the reflected / scattered light A and B from each other. The light may be detected by the photodetector 15. Also,
Although the determination unit 12 and the main control unit 10 are provided separately, they may be integrated. The determination unit 12 and the main control unit 10
May be configured by dedicated hardware, or may be implemented as a control program for a general-purpose microprocessor.

The measuring laser a is irradiated onto the surface of the wafer 1 at an incident angle θ1 substantially perpendicular to the surface of the wafer 1, and the measuring laser b
Is irradiated onto the surface of the wafer 1 at an incident angle θ2 inclined to, for example, 20 degrees or less.

When the irradiation angle is set as described above, as shown in FIG. 5, the measuring laser a having a substantially perpendicular incident angle θ1 is largely reflected / scattered on both the particles and the pits on the wafer 1. , The amount of the reflected / scattered light A increases both for the particles and the pits. Accordingly, by setting the threshold value to be equal to or less than the amount of the reflected / scattered light A detected by each of the particles and the pits in the determination unit 12, it is possible to detect both the particles and the pits with the measuring laser a. Become.

On the other hand, as shown in FIG. 5, the quantity of the reflected / scattered light B of the measuring laser b irradiated at an inclined incident angle θ2 with respect to the surface of the wafer 1 protrudes from the surface of the wafer 1. Larger for existing particles but smaller for concave pits. Therefore, by setting the threshold value in the middle of the amount of the reflected / scattered light B in the case of each of the particles and the pits in the determination unit 12, the measurement laser b can detect only the particles.

The two laser light sources 13 and 14 used here are both pulse oscillations, and as shown in the diagram of FIG. 3, by the timing control signals 11a and 11b from the oscillation timing control unit 11, The oscillation timing of each is shifted, and while the measurement laser a is irradiating the wafer 1, the oscillation of the measurement laser b is turned off and the measurement laser b is not irradiated to the wafer 1, and the measurement laser b is irradiated to the wafer 1. During the irradiation, the oscillation of the measuring laser a is turned off so that the measuring laser a is not irradiated to the wafer 1. Also, the determination unit 12 determines the timing control signal 1
The determination operation is performed in synchronization with 1a and 11b.

FIG. 2 shows a wafer 1 according to this embodiment.
FIG. 4 is a plan view showing an example of a method of irradiating a laser beam for measurement a and a laser beam for measurement b. In this embodiment, in order to classify particles and pits such as COPs in one measurement by shifting the oscillation timing of the two lasers for measurement of pulse oscillation a and laser b for measurement, the respective laser irradiation regions are as follows. Set as shown.

When the measurement laser b is OFF, the irradiation area of the measurement laser a is 5 (S1), and the measurement laser a is OF
The irradiation area of the measurement laser b at F is set to 6 (S2). That is, assuming that the time lag between the laser oscillation timings of the measurement lasers a and b is Δt and the scan speed of the wafer 1 is v, when the measurement laser a irradiates the irradiation area 5, the next measurement laser b Is set to be an area advanced from the irradiation area 5 by Δt at the scan speed v. In this state, stage 2
A spiral scan combining rotation and linear displacement of is performed to measure the entire area of the wafer 1.

Note that under the control of the table driver 16,
By changing the rotation speed of the stage 2 by the rotation motor 2a in accordance with the linear displacement by the linear motor 2b, the linear speed in the circumferential direction of the irradiated portion of the wafer 1 with the measurement lasers a and b is kept constant. Lasers a and b
While the deviation time Δt of the laser oscillation timing is kept constant, the entire area of the wafer 1 can be spirally scanned by the measuring lasers a and b with uniform detection accuracy.

Hereinafter, an example of the operation of the appearance inspection method and apparatus of the present embodiment will be described.

First, while the stage 2 supporting the wafer 1 is rotated by the rotary motor 2a and linearly displaced in the radial direction by the linear motor 2b, the distance (Δt × scan speed v) in the scanning direction is as described above. The spiral scanning is started by alternately irradiating the shifted laser beams with the measuring lasers a and b. During this scanning, the determination unit 12 outputs a timing control signal 11a obtained from the oscillation timing control unit 11.
And the photodetector 1 in synchronization with the timing control signal 11b.
By comparing the magnitude of the amount of reflected / scattered light A and B of each of the measuring lasers a and b detected at 5 with the threshold value set as described above, a defect detected by the measuring laser a (particle Or a detection signal of each detection defect (only particles) by the measurement laser b to the main control unit 10. The main control unit 10 outputs the detection result by the measurement laser a to N1 and the measurement laser b.
Is set as N2, and the respective detection numbers are individually accumulated.

After one scan of the wafer 1 is completed, the main control unit 10 outputs N1−N2 as the number of detected COPs and N2 as the number of detected particles, and the storage device 10a.
Is recorded in the inspection result table 20. Thus, the number of particles and COPs can be individually measured by one scan.

In addition, as described below, the inspection can be performed while individually determining the type of each defect during scanning.

During the scanning of the wafer 1 by the measuring lasers a and b as described above, the judging unit 12 sends a signal from the oscillation timing control unit 11 according to the logic illustrated in the flowchart of FIG. 4 and FIG. In synchronization with the obtained timing control signal 11a and timing control signal 11b, a determination is made based on the magnitude of each detected light amount of the reflected / scattered light A and B of the measuring lasers a and b.

That is, it is determined whether or not a defect has been detected by the measuring laser a (step 101).
Further, it is determined whether or not the defect is detected by the measuring laser b (step 102). If it is, the defect corresponds to case III in FIG. 6, so that the defect is determined to be a particle, and the detection signal of the particle is used as the main control signal. The main control unit 10 transmits the particle detection information together with the current scanning position obtained from the table driver 16, that is, the detected coordinates in the wafer 1 to the storage unit 10 a. It is recorded in the inspection result table 20.

On the other hand, in step 102, the measurement laser b
If not detected, the case corresponds to case IV in FIG. 6, the defect is determined to be a COP, and a detection signal of the COP is transmitted to the main control unit 10 (step 104), and the main control unit 10 The COP detection information is recorded in the inspection result table 20 of the storage device 10a together with the scanning position at that time obtained from the table driver 16 as needed, that is, the detection coordinates in the wafer 1.

If no defect is detected in step 101, it corresponds to either case I or case II in FIG. 6, but no special operation is performed in case I since there is no defect. In addition, since the case II is not possible, the presence / absence of the case II can be applied to the error detection of the appearance inspection apparatus (determining an error when the case II appears) and the sensitivity adjustment.

This determination process is performed while the entire area of the wafer 1 is scanned once by the measuring lasers a and b, so that the presence / absence (number), position, etc. of a defect in the wafer 1 that distinguishes the particle from the COP are determined. Can be obtained.

Further, since the appearance inspection is completed only by scanning the entire area of the wafer 1 once, compared with the conventional case where the scanning is performed a plurality of times for the individual detection of the particles and the COPs. Thus, it is possible to greatly improve the throughput in the appearance inspection process.

In the above description, the measuring lasers a and b
The technique of separating the inspection results of the two by shifting the irradiation timings of the two is exemplified. However, lasers of different wavelengths are used as the measurement laser a and the measurement laser b, and the photodetector 1 is used.
On the side of No. 5, the present invention includes discriminating the inspection results of the two by detecting each of the reflected / scattered light A and the reflected / scattered light B through a filter that selectively transmits the wavelength. When lasers having different wavelengths are used, it is not necessary to shift the irradiation timing and position, and the result can be determined in parallel by continuous irradiation on the same portion of the wafer 1.

Next, an example of a method of manufacturing a semiconductor device of the present invention in which the above-described appearance inspection technique of the present invention is applied to a manufacturing process of a semiconductor device will be described with reference to the flowchart of FIG.

In the wafer process, the presence of COPs (pits) on the surface of the CZ crystal wafer, which is a material, in addition to the adhering foreign matter such as particles that can be removed by cleaning, indicates the quality of the wafer process formed thereon. And causes a decrease in yield. Therefore, it is necessary to control the number of COPs, which cannot be removed by cleaning, on the surface of the CZ wafer used as a material for the wafer process to a predetermined value or less.

Therefore, the wafer 1 before the wafer process is used.
By applying the above-described appearance inspection technique of the present invention to the COP inspection, an improvement in the throughput of the entire process can be expected.

First, a single crystal ingot of a semiconductor such as Si is manufactured by the single crystal pulling (CZ) method (step 20).
1) A wafer is prepared by slicing the single crystal ingot (Step 202), and the surface of the wafer is mirror-polished (Step 203).

After that, first, the polished wafer is cleaned by a method such as RCA cleaning (Step 204), and then a visual inspection is performed using the visual inspection method and apparatus of the present invention as described above (Step 205).

Then, based on the result of the appearance inspection in step 205, it is determined whether or not the number of COPs is equal to or less than a predetermined value (step 206). If it is determined that the value is equal to or more than the specified value, the wafer 1 is determined to be unusable for the wafer process and is excluded (step 212). On the other hand, COP
If the number is less than or equal to the specified value, it is further determined whether or not the number of attached foreign matters such as particles is equal to or less than a predetermined specified value (step 207). Again, the process returns to the cleaning and visual inspection steps of step 204 and subsequent steps.

On the other hand, the wafer 1 for which it is determined in step 207 that the number of adhered foreign substances is smaller than the specified value is subjected to a well-known wafer process for forming a circuit pattern by photolithography and the like, and a predetermined semiconductor circuit pattern is formed. After the step (Step 208), a dicing step for dividing the wafer 1 into pellets (Step 209), a bonding step such as pellet bonding or wire bonding (Step 210), and a packaging step for sealing the pellet (Step 211) , Etc., and shipped as a desired semiconductor device.

As described above, according to the method of manufacturing a semiconductor device of the present embodiment, in the appearance inspection step in which the COP needs to be discriminated from foreign matter such as particles and inspected, the COP of the wafer 1 is scanned by one scan. Since the number can be accurately inspected separately from the particles, it is possible to quickly obtain an accurate inspection result such as the number of COPs, thereby improving the yield and the throughput in the semiconductor device manufacturing process.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the above-described embodiments, and can be variously modified without departing from the gist thereof. Needless to say, there is.

For example, in the description of the above embodiment,
Although the case where the irradiation angles of the two measurement lasers are made different as a method of giving a difference in the detection sensitivity to particles and COP has been described, other methods capable of giving a difference in the detection sensitivity may be adopted. .

[0054]

Advantageous effects obtained by typical ones of the inventions disclosed in the present application will be briefly described.
It is as follows.

According to the appearance inspection method of the present invention, it is possible to obtain an effect that different kinds of defects of an object can be distinguished and detected by one measurement.

Further, according to the appearance inspection method of the present invention, it is possible to improve the throughput in the appearance inspection step.

According to the appearance inspection apparatus of the present invention,
An effect is obtained in that different types of defects of the object can be distinguished and detected by the measurement of each time.

Further, according to the appearance inspection apparatus of the present invention, there is an effect that the throughput in the appearance inspection step can be improved.

According to the method of manufacturing a semiconductor device of the present invention,
The effect that the yield and the throughput in the manufacturing process of the semiconductor device can be improved can be obtained.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram illustrating an example of a configuration of a visual inspection device that performs a visual inspection method according to an embodiment of the present invention.

FIG. 2 is a plan view showing an example of the operation of a visual inspection device that performs a visual inspection method according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating an example of an operation of a visual inspection device that performs a visual inspection method according to an embodiment of the present invention.

FIG. 4 is a flowchart illustrating an example of an operation of a determination logic of a visual inspection device that performs a visual inspection method according to an embodiment of the present invention.

FIG. 5 is an explanatory diagram showing an example of the operation of the determination logic of the appearance inspection device that performs the appearance inspection method according to the embodiment of the present invention;

FIG. 6 is an explanatory diagram showing an example of the operation of the determination logic of the visual inspection device that performs the visual inspection method according to one embodiment of the present invention.

FIG. 7 is a flowchart illustrating an example of a method of manufacturing a semiconductor device employing an appearance inspection apparatus that performs an appearance inspection method according to an embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 wafer 2 stage 2a rotation motor 2b linear motor 3 measurement laser (a) 4 measurement laser (b) 5 measurement laser (a) irradiation area 6 measurement laser (b) irradiation area 10 main control unit 10a storage Apparatus 11 Oscillation timing control unit 11a Timing control signal 11b Timing control signal 12 Judgment unit 13 Laser light source 14 Laser light source 15 Photodetector 16 Table driver 20 Inspection result table A Reflection / scattered light of measurement laser (a) B Measurement laser (B) Reflected / scattered light θ1 Irradiation angle of measurement laser (a) θ2 Irradiation angle of measurement laser (b)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2G051 AA51 AB01 AB02 AB07 BA01 BA08 BA10 CA02 CB01 CB05 CC07 DA07 EA14 EB01 EB02 EC01 4M106 AA01 BA05 CA19 CA41 CB19 DB03 DB08 DB09 DB15 DB21 DJ18 DJ20

Claims (10)

[Claims] 1. A light amount of scattered light generated from an irradiated portion of each of the first and second lasers of the object when the surface of the object is irradiated with at least two first and second lasers. A visual inspection method characterized by detecting the size of the defect to discriminate the type of a defect present on the surface of the object. 2. The appearance inspection method according to claim 1, wherein
An appearance inspection method, wherein the object is irradiated with the first and second lasers at different incident angles. 3. The appearance inspection method according to claim 1, wherein the first and second lasers are alternately radiated to the object in pulses at different timings, and the illuminated part is irradiated with the first and second lasers. A method of individually detecting the magnitude of the amount of scattered light generated from each irradiation site of the first and second lasers by shifting the object in the scanning direction of the object by the first and second lasers, or Lasers having a plurality of wavelengths different from each other are used as the first and second lasers, and the scattered lights having different wavelengths generated from the irradiation portions of the first and second lasers having different wavelengths are selectively converted to the wavelengths. And selectively detecting the magnitude of the amount of scattered light generated from each of the irradiated portions of the first and second lasers by selectively detecting through a filter that transmits or blocks light. Law, appearance inspection method which comprises using any of the methods. 4. The appearance inspection method according to claim 1, wherein the defect is one of particles attached to the surface of the object and pits formed on the surface of the object. The particle and the pit are both detected by the first laser irradiated at the incident angle substantially perpendicular to the surface of the object, and at the incident angle inclined with respect to the surface of the object. Only the particles are selectively detected by the irradiated second laser, and the combination of the detection results of the defects by the first and second lasers indicates that the defect is one of the particles and the pits. A visual inspection method characterized in that it is discriminated whether or not it is. 5. A plurality of laser sources for irradiating at least two first and second lasers on a surface of an object; and moving the supported object relative to the laser source. An inspection table that scans the object with the first and second lasers, and a photodetector that detects scattered light generated from each of the irradiated portions of the object with the first and second lasers. And a determination logic for discriminating a type of a defect existing on the surface of the object based on the magnitude of the amount of the scattered light detected by the photodetector. . 6. The visual inspection device according to claim 5, wherein the plurality of laser sources are arranged so that the first and second lasers have different incident angles with respect to the object. A visual inspection device characterized by the following. 7. The appearance inspection apparatus according to claim 5, wherein the laser sources are different such that the first and second lasers are alternately applied to the object in pulses at different timings. With pulse oscillation at the timing,
The irradiation part is set so as to be shifted in a scanning direction of the object by the first and second lasers, and the photodetector is configured to synchronize the first and second laser sources with each other in synchronization with the pulse oscillation of each of the plurality of laser sources. And a configuration for individually detecting the magnitude of the amount of scattered light generated from each irradiation site of the second laser, or each of the plurality of laser sources emits the first and second lasers having different wavelengths from each other. Oscillates, and the photodetector emits the scattered light having different wavelengths generated from the irradiation sites of the first and second lasers having different wavelengths,
A configuration in which the wavelength is selectively detected through a filter that selectively transmits or blocks the wavelength to individually detect scattered light generated from each irradiation site of the first and second lasers. A visual inspection device characterized by comprising: 8. The visual inspection device according to claim 5, wherein the defect is one of particles adhered to the surface of the object and pits formed on the surface of the object. The particle and the pit are both detected by the first laser irradiated at the incident angle substantially perpendicular to the surface of the object, and at the incident angle inclined with respect to the surface of the object. The second laser that is irradiated selectively detects only the particles, and the determination logic determines that the defect is the particle and the defect based on a combination of the detection results of the defect by the first and second lasers. An appearance inspection device that distinguishes between pits. 9. A method for manufacturing a semiconductor device for forming a circuit pattern on a semiconductor wafer, the method comprising: inspecting an appearance of the semiconductor wafer according to claim 1, 2, 3, or 4; A method for manufacturing a semiconductor device, comprising using the visual inspection device described in 6, 7, or 8. 10. The method of manufacturing a semiconductor device according to claim 9, wherein the appearance inspection is performed by discriminating and inspecting a foreign substance attached to a polishing wafer to be subjected to a wafer process and a pit present on the surface of the polishing wafer. A method for manufacturing a semiconductor device, which is an inspection.