JPH11351850A - End damage inspection method and device - Google Patents

Abstract

(57) [Problem] To provide a longitudinal flaw by measuring both scattered reflected light scattered due to a flaw in the regular reflection direction and scattered reflected light scattered in other directions in the case where there is no flaw. To provide an end flaw inspection method and apparatus capable of accurately detecting a flaw regarded as a defect generated at an end, such as a lateral flaw, an oblique flaw, and a rough surface roughness. . SOLUTION: Coherent light is applied to an inspected end of an object to be inspected, and the coherent light is scattered and reflected in a specular direction reflected by a flaw of the inspected end in the vicinity of the inspected end. The lateral end of the inspected end is detected and specified based on the amount of received light.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an edge flaw inspection method and apparatus for optically inspecting the edge of a plate-shaped article such as a silicon wafer or a semiconductor wafer.

[0002]

2. Description of the Related Art When inspecting the presence or absence of a large flaw, such as a crack, a chip, or a polishing flaw, on a narrow and long end such as an outer peripheral edge of a silicon wafer 1, which is recognized as a defect in the end. Specular reflection light generated by reflection of the irradiated laser light at the end is cut off, only scattered reflection light is received, and a flaw is specified based on the amount of scattered reflection light received.

When the end face 1a of the silicon wafer 1 is viewed from the front, as shown in FIG. 8, if the end face 1a has a flaw and the flaw is a vertical flaw 2 extending in the vertical direction (FIG. 8).
(A)) Generally, the incident laser light is more strongly scattered in the left-right direction (FIG. 8B). In this case, as shown in FIGS. 9 and 10, the elliptical mirror 3 having the position of the end face 1a as the first focal point is used, and the detector 4 disposed at the position of the second focal point is scattered and reflected in the left-right direction. By condensing the light and measuring the amount of light, the longitudinal flaw 2 can be detected and specified.

[0004] Similarly, as shown in FIG. 11, if the flaw generated on the end face 1a is a horizontal flaw 5 extending in the horizontal direction (FIG. 11).
(A)) Generally, the incident laser light is more strongly scattered in the vertical direction (FIG. 11B). In this case, as shown in FIGS. 12 and 13, the scattered reflected light is collected on the detector 4 disposed at the position of the second focal point, and the lateral flaw 5 is detected and specified based on the amount of the scattered reflected light.

[Problem] In such a conventional edge flaw inspection method, the light shielding means 7 for shielding the specularly reflected light from the edge is extended vertically to reach the inner surface of the elliptical mirror 3. Since the laser beam is formed in a band shape and provided between the light source 6 and the inspection object 1, when the defect is a lateral wound, the laser beam is applied to the lateral wound and the light is shielded by the light shielding means 7. Therefore, even if an attempt is made to condense the scattered reflected light on the detector 4 disposed at the position of the second focal point, the amount of condensed light is small, the detection sensitivity of the flaw becomes extremely low, and the lateral flaw is detected. There is a problem that cannot be specified accurately.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the problems in the prior art, and a specific problem set to solve the problems is to solve the problem in the case where there is no flaw. By measuring both the scattered reflected light scattered due to the presence of a scratch in the regular reflection direction and the scattered reflected light scattered in the other direction, vertical scratches, lateral scratches, oblique scratches, and rough surface roughness It is an object of the present invention to provide an edge flaw inspection method and apparatus capable of accurately detecting a flaw regarded as a defect generated at an edge.

[0007]

Means for Solving the Problems Claim 1 of the present invention
The end flaw inspection method according to the above, irradiates coherent light to the inspected end of the object to be inspected, scattered reflected light in the regular reflection direction reflected by the coherent light by the scratches of the inspected end, the inspected Light is received in the immediate vicinity of the end, and a lateral flaw of the inspected end is detected and specified based on the amount of received light.

[0008] According to a second aspect of the present invention, there is provided an end flaw inspection method.
Furthermore, the scattered reflected light other than the scattered reflected light in the specular reflection direction reflected by the flaw of the inspected end portion of the coherent light is received at a position different from the light receiving position of the scattered reflected light in the specular reflection direction, Based on the amount of each scattered reflected light received, vertical scratches, horizontal scratches,
In addition, oblique flaws are detected and specified.

[0009] Further, according to a third aspect of the present invention, there is provided an end flaw inspection apparatus.
An optical system for irradiating coherent light, a holding device for movably holding the object to be inspected relative to the optical system, and a device for irradiating coherent light to an inspected end of the object to be moved relatively. Second to receive scattered reflected light in the specular direction
And light receiving means.

[0010] Further, according to a fourth aspect of the present invention, there is provided an end flaw inspection apparatus.
It is characterized in that it comprises a first light receiving means for receiving scattered reflected light when coherent light is applied to the inspected end of the inspected object which moves relatively.

[0011] Further, according to a fifth aspect of the present invention, there is provided an end flaw inspection apparatus.
The second light receiving means is a combination of two or more light receiving elements or a light receiving element array in which two or more light receiving elements are combined.

[0012] The edge flaw inspection apparatus according to claim 6 is
When the second light receiving means arranges the inspected end portion at or near a first focal position of the elliptical mirror, the first light receiving section of the elliptical mirror is moved to the first position.
A light receiving element for receiving light immediately near the focal position is provided.

[0013] In addition, the edge flaw inspection device according to claim 7 is
The holding device is a rotary table for holding a disk-shaped wafer.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below. However, this embodiment is specifically described for better understanding of the gist of the invention, and does not limit the content of the invention unless otherwise specified. In addition, the same parts as those in the related art are denoted by the same reference numerals, and description thereof is omitted.

[Inspection Method] In the edge flaw inspection method according to the embodiment, a laser beam is irradiated as a coherent light to an inspection end of a silicon wafer 1 as an inspection object, and the laser light is irradiated at the inspection end. The end surface condition is analyzed based on the reflected light.

In the vicinity of the inspected end, scattered reflected light (hereinafter simply referred to as scattered reflected light in the regular reflection direction) reflected from the scratch in the regular reflection direction when there is no flaw is received. At a position different from the light receiving position of the scattered reflected light, the scattered reflected light in the other direction is received, and based on the received light amount of the received scattered reflected light, based on the presence or absence of a vertical flaw, a lateral flaw, or an oblique flaw, The surface condition of the inspected end portion is inspected, for example, the surface roughness is determined based on the amount of received regular reflection light and scattered reflection light.

[Optical System Measuring Unit] As an optical system measuring unit to which such an inspection method is applied, as shown in FIGS.
The elliptical mirror 3 is used as a reflecting mirror, and the inspected end 1b of the silicon wafer 1 is positioned at the first focal position of the elliptical mirror 3, and the second
A detector 4 for receiving scattered reflected light is arranged at the focal position,
A light source 6 is provided between the inspected end 1b and the detector 4, and scattered reflected light in the specular reflection direction is located immediately above and immediately below the inspected end 1b at the first focal position. Is formed by arranging a detector 11 that receives the light.

As for the relative positional relationship between the parts, the light source 6 is arranged so that the laser light is irradiated vertically on the end face 1a of the end 1b to be inspected. The axis of the elliptical mirror 3 in the major axis direction may be slightly shifted (about 4 °) with respect to the optical axis of the light source 6 so that the light receiving element of the arranged detector 4 does not overlap.

The light source 6 includes at least He having a wavelength of 633 nm.
Ne laser light or semiconductor laser light having a wavelength of 685 nm can be irradiated to the end 1b to be inspected.
The wavelength of the laser light may be a wavelength in the infrared region,
Those having a visible light wavelength are desirable from the viewpoint of easy adjustment. Further, it is desirable that the beam diameter when the laser beam is irradiated perpendicularly to the end face 1a of the silicon wafer 1 is slightly larger than the thickness of the silicon wafer 1 in consideration of the swing during rotation of the wafer.

The detector 4 disposed at the second focal point for measuring the general scattered reflected light is mainly used for inspection for longitudinal flaws, and is provided with a PD (photodiode; not shown).
The used detector is formed. The detector 11 arranged in the immediate vicinity of the first focal position to measure the scattered reflected light in the specular reflection direction is mainly used for a lateral damage inspection. As shown in FIG. Photodiode) 1
The photodetector arrays 11a in which 10 elements 2 are assembled in one row are combined in a chevron to form a detector in which a total of 40 PDs 12 are arranged in one row.

As shown in FIGS. 1 to 3, the detectors 11 are compactly arranged so as not to shield scattered reflected light other than scattered reflected light in the regular reflection direction, and are arranged one at each of the upper and lower parts. Almost all of the specularly reflected light from the inspected end 1b having no flaw can be shielded, and almost all of the scattered reflected light from the inspected end 1b in the specular reflection direction when there is a flaw can be shielded. It is placed and installed so that it can receive light.

[Inspection Apparatus] An end flaw inspection apparatus having such an optical system measuring section is formed so as to partially cover the silicon wafer 1 and has an optical system measuring section built in as shown in FIG. And a wafer rotating stage 2 on which the silicon wafer 1 is placed and rotated at a constant rotational speed about a vertical axis.
2, an image recognizing unit 23 having a CCD camera for recording defects of the inspected end 1b detected by the measuring unit 21 in an image form, and a robot arm for placing the silicon wafer 1 on the wafer rotating stage 22. 24, a wafer transfer device 25 for transferring the silicon wafer 1 transferred to the wafer rotation stage 22 to a position where it can be taken out by the robot arm 24, a normal wafer storage box 26 for storing the silicon wafer 1 that has passed the inspection, NG wafer storage box 27 for storing the converted silicon wafer 1
And a gantry 28 in which these are arranged on the upper surface side.

In order to make the measuring unit 21 compact, the plane mirror 6a is arranged at the position of the light source 6 shown in the optical system measuring unit, as shown in FIGS. By setting a direction of the plane mirror 6a so that a laser beam from the laser transmitter is reflected by the plane mirror 6a and hits the inspected end 1b, and fixed. You may make it possible to reduce the size of the housing part in the measuring unit.

As shown in FIG. 6, the measurement data processing unit of the end flaw inspection apparatus is divided into a scattered light measurement system and a scattered reflection light measurement system in the regular reflection direction, each of which is a DC (direct current signal).
It is divided into an amount measuring system and an AC (AC signal) amount measuring system. The DC amount measurement system of the scattered light measurement system performs an IV conversion of the output of the detector 4 to amplify the output, and a low-pass filter (LP) for cutting high frequency noise of the amplified signal.
F) 32 and A for converting an analog signal to a digital signal
It comprises a D conversion board 34 and a data processing device 35 which receives signals from the AD conversion board 34 and processes data. The AC amount measurement system of the scattered light measurement system is obtained by adding a high-pass filter (HPF) 33 that cuts a large swell of a signal and a DC component after the low-pass filter of the DC amount measurement system.

The DC amount measuring system in the system for measuring the scattered reflected light in the regular reflection direction includes a light receiving element array 11a of the detector 11,
An amplifier 36 that performs IV conversion and amplifies an output obtained by adding all outputs of the PDs 12 incorporated in the PD 11a, a low-pass filter 37 that cuts high-frequency noise of the amplified signal, and converts an analog signal into a digital signal. A to convert
It comprises a D conversion board 34 and a data processing device 35 which receives signals from the AD conversion board 34 and processes data. Further, the AC amount measuring system in the scattered reflected light measuring system in the specular reflection direction inputs the output signal of the detector 11 in such a manner as to individually correspond to each PD 12 incorporated in the light receiving element arrays 11a, 11a. Amplifier 3 to convert and amplify
, 36n, and a low-pass filter (LPF) 37 for cutting high-frequency noise of the amplified signal.
a, 37b,..., 37n and a high-pass filter (HPF) 38 for cutting large undulations and DC components of the signals.
a, 38b,..., 38n;
And a bias circuit 40 for applying a bias voltage of 2.5 V to each signal in order to process the captured AC signal in a range of 0 to 5 V, and an AD conversion for uniformly converting an analog signal of 2.5 V applied to a digital signal. Board 34 and AD
And a data processing device 35 for inputting a signal from the conversion board 34 and processing the data.

The wafer rotating stage 22 includes a motor 22a
Driven by the rotary encoder 41
And inputs it to the data processing device 35. The position of the flaw when the silicon wafer 1 is rotating is determined by the output signal from the rotary encoder 41 for detecting the rotation of the wafer rotating stage 22 and the position of the notch (or orientation flat) 1c provided in advance on the inspected end 1b. Is determined by the rotation angle from the position of the notch 1c based on the sensor output signal for detecting

The signal obtained by the AC amount measurement system has a detector for detecting a flaw and a signal intensity which differs depending on the type of a flaw such as a crack or a chip. Can also be performed. As for the surface roughness, the surface roughness of the inspection object can be detected by comparing the scattered reflected light and the specular reflected light of the signal obtained by the DC measurement system.

For example, to detect a flaw called a lateral flaw that enters a direction parallel to the wafer surface among cracks, when the detector 11 receives the scattered reflected light in the regular reflected light direction, the light is received by each PD 12. The signal is converted into an electric signal of a voltage corresponding to the amount of received light, amplified, noise is removed, large swells and DC components of the signal are cut, and each multi-channel signal is converted into one channel or an AD conversion board 34.
When the input range of the AD conversion board 34 is set to, for example, 5 V,
A 2.5V bias is applied, and the signal is converted into a digital signal and input to the data processing device 35.

On the other hand, to detect a flaw called a vertical flaw which enters the wafer surface in the direction perpendicular to the crack, when the scattered reflected light is received by the detector 4, it is converted into an electric signal of a voltage corresponding to the received light amount. Then, the signal is amplified, noise is removed, a large swell and a DC component of the signal are cut, and the signal is converted into a digital signal and input to the data processing device 35. When the measurement data is input as a digitized signal, the data processing device 35 evaluates the presence or absence of a flaw based on the measurement data.

As shown in FIG. 7A showing the signal obtained by the detector 4, the presence or absence of a flaw is determined by setting the upper limit value as a threshold value, and when there is data exceeding the threshold value, It is determined that a scratch exists at an angle corresponding to. Also, as shown in FIG. 7B showing the signals obtained by the PDs 12,..., 12 of the detector 11, the upper limit value and the lower limit value set in a certain width from the average value are input as threshold values. If the data deviates from the range of the threshold, it is determined that a flaw corresponding to the deviated data exists at a position of the deviated data.

In particular, a flaw detected only by the detector 4 is determined to be a vertical flaw, hardly detected by the detector 4, and detected by any one of the PDs 12,. The wound is determined to be a lateral injury. If there is a PD 12 that detects the surface roughness or polishing marks as scratches,
The detection sensitivity of the flaw can be set depending on how many PDs 12 are detected at the same angle. For example, when the number of detected PDs of a flaw at a certain angle is six, it is determined to be a lateral flaw and 5
In the two cases, it is not judged as a scratch because of surface roughness or polishing marks. In addition, when the detector 4 and the detector 11 detect a flaw at the same angle, it is determined that the flaw is an oblique flaw or a chipped flaw called a chip. In particular, in the case of a chip, since the output from the detector 4 is large, a chip with a small output from the detector 4 is determined as an oblique scratch, and a chip with a large output is determined as a chip.

The degree of the surface roughness is obtained by the amount of received light A of the scattered reflected light received by the detector 4 and obtained by the DC amount measuring system, and by the DC amount measuring system of PDs 12,... Based on the total received light amount B, as the surface roughness of the end portion becomes rougher, the amount of specular reflection light received by the detector 11 decreases and the amount of scattered light received by the detector 4 increases, so that A or B or A / B, B / A, etc.
The degree of roughness can be calculated. When calculated by adding the total amount of received light, the average surface roughness of the silicon wafer 1 is expressed, and by calculating for each angle, the distribution of the surface roughness of the wafer end surface can be obtained. Further, by knowing the distribution state of the surface roughness, the degree of the roughness can be reflected on the threshold value for flaw detection, thereby preventing erroneous determination. For example, if the surface roughness is a rough angle, the threshold value for scratch determination is increased, and the threshold value is automatically changed so that a signal due to the surface roughness is not detected as a scratch. The threshold can be automatically lowered to prevent the wound from being missed.

[Function and Effect] As described above, in the edge flaw inspection method according to the embodiment, the reflected light scattered in the vertical direction by the lateral flaw is detected by the detector 11 arranged at the vertical position immediately near the inspected end. Can be received, the detection sensitivity of the lateral flaw increases, and the lateral flaw can be accurately evaluated.

Also when specifying the surface roughness, the reflected light immediately near the inspected end is received by the detector 11 and the vicinity of the inspected end which cannot be measured by the detector 4 disposed at the second focal position. Can be compensated for the amount of reflected light received, and the inspection accuracy of surface roughness can be made more accurate.

In the edge flaw inspection apparatus, the disk-shaped silicon wafer 1 is mounted on a wafer rotating stage 22 and rotated at a constant rotation speed, and the laser light from the light source 6 is transmitted through a plane mirror 6a. Irradiating the end surface of the silicon wafer 1 makes it possible to easily inspect the end surface of the silicon wafer 1 over the entire circumference, thereby shortening the inspection time and improving the inspection efficiency.

The reflected light reflected by the end face of the silicon wafer 1 is received by a detector 11 provided in the optical measuring section, which is disposed in the vicinity of an end to be inspected, and the elliptical mirror 3
The light is condensed on the detector 4 through the detector, so that both the regular reflection light and the scattered reflection light do not generate a large amount of unreceived light. Scratches, lateral scratches, oblique scratches between them, surface roughness and the like can be evaluated.

Detector 11 disposed immediately near the end to be inspected
By forming a detector in which a combination of two or more light receiving elements or a combination of two or more light receiving elements are arranged substantially in the irradiation direction, the reflected light of the laser light applied to the end to be inspected is received. Even if the light is scattered in the vertical direction of the inspection end, the scattered reflected light is reliably received by the detector 11,
The amount of reflected light that is not received with respect to the total amount of reflected light is small enough to be within the range of error. The reliability of the edge flaw inspection can be improved.

[0038]

As described above, according to the present invention, in the edge flaw inspection method according to the first aspect, when the coherent light applied to the inspected end of the inspected object is reflected by the flaw of the inspected end, The scattered reflected light in the specular reflection direction is received in the immediate vicinity of the inspected end, and the lateral damage of the inspected end can be detected and specified based on the amount of received light. Scattered reflected light in the reflection direction can be measured without causing light reception failure due to light shielding, and the detection sensitivity of flaws, especially lateral flaws, is increased, and lateral flaw detection can be detected accurately, and edge flaw inspection can be performed accurately. it can.

In the edge flaw inspection method according to a second aspect of the present invention, in the specular reflection direction, the scattered reflection light other than the scattered reflection light in the specular reflection direction of the coherent light reflected by the flaw of the inspected end is reflected. Scattered reflected light in the specular direction by detecting and identifying vertical, horizontal, and oblique flaws based on the amount of scattered reflected light received. An oblique flaw is specified based on the ratio of the amount of scattered reflected light in the specular reflection direction and the amount of other scattered reflected light. Can be specified, and the accuracy of the edge flaw inspection can be improved, and the reliability of the inspection can be greatly improved.

Further, in the edge flaw inspection apparatus according to the third aspect, an optical system for irradiating coherent light, a holding device for holding the object to be inspected relatively movable with respect to the optical system, and And a second light receiving means for receiving the scattered reflected light in the specular reflection direction when the coherent light is applied to the inspected end of the inspected object, thereby detecting the lateral damage accurately and accurately. A possible end flaw inspection device can be realized.

Further, in the edge flaw inspection apparatus according to the fourth aspect, the first light receiving means for receiving the scattered reflected light when the coherent light is applied to the inspected end of the relatively moving inspected object is provided. With this arrangement, it becomes possible to measure both the general scattered light and the scattered reflected light in the regular reflection direction by the first and second light receiving means, and to measure both the longitudinal direction and the lateral direction of the flaw. The type and the direction of the flaw can be detected with high accuracy by enabling accurate detection.

Further, in the end flaw inspection apparatus according to claim 5, the second light receiving means is a light receiving element array combining two or more light receiving elements or a light receiving element array combining two or more light receiving elements. It is possible to receive the scattered reflected light in the specular reflection direction as much as possible, and it is possible to accurately detect the lateral flaw.

Further, in the edge flaw inspection apparatus according to claim 6, when the second light receiving means arranges the inspected end portion at or near the first focal position of the elliptical mirror, the second light receiving means can detect the position of the elliptical mirror. The provision of the light-receiving element that receives light in the immediate vicinity of one focal point position enables light to be scattered and reflected in the direction of specularly reflected light, and allows the evaluation of a scratch in the lateral direction based on the amount of received light.

Further, in the edge flaw inspection apparatus according to the seventh aspect, since the holding device is a rotary table for holding the disk-shaped wafer, the entire surface of the disk-shaped wafer can be easily inspected online and mass-produced. Inspection of a disk-shaped wafer can be performed quickly, processing efficiency can be improved, and inspection costs can be reduced by lowering inspection costs.

[Brief description of the drawings]

FIG. 1 is an explanatory side view showing an optical system measurement unit according to the present invention.

FIG. 2 is an explanatory plan view showing an optical system measurement unit according to the present invention.

FIG. 3 is an explanatory plan view showing a light receiving element array of the optical system measurement unit according to the embodiment of the present invention.

FIG. 4 is a perspective view showing an edge flaw inspection apparatus according to the embodiment of the present invention.

FIGS. 5A and 5B are schematic explanatory views showing an optical system measuring unit according to the embodiment of the present invention, wherein FIG. 5A is a plan explanatory view and FIG.

FIG. 6 is an explanatory block diagram showing a data processing system according to the embodiment of the present invention.

7A and 7B are graphs for explaining a flaw inspection evaluation method according to the embodiment of the present invention, in which FIG. 7A is a flaw inspection evaluation graph when an upper limit is set as a threshold, and FIG. It is a flaw inspection evaluation graph when an upper limit and a lower limit set by width are set as a threshold.

8A and 8B are front explanatory views showing a vertical flaw and light reflection state in a conventional vertical flaw inspection, wherein FIG. 8A is a front explanatory view showing an end face when there is a vertical flaw, and FIG. It is a front explanatory view showing a reflection situation.

FIG. 9 is an explanatory side view showing a vertical flaw inspection state in an optical system measurement section of a conventional edge flaw inspection apparatus.

FIG. 10 is an explanatory plan view showing a vertical flaw inspection state in an optical system measurement unit of a conventional edge flaw inspection apparatus.

11A and 11B are front explanatory views showing a state of a side flaw and light reflection in a conventional lateral flaw inspection, wherein FIG. 11A is a front view showing an end face when there is a lateral flaw, and FIG. It is a front explanatory view showing a reflection situation.

FIG. 12 is an explanatory side view showing a lateral flaw inspection state in an optical system measurement unit of a conventional edge flaw inspection apparatus.

FIG. 13 is an explanatory plan view showing a lateral flaw inspection state in an optical system measurement unit of a conventional edge flaw inspection apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Silicon wafer 1a End surface 2 Longitudinal flaw 3 Elliptic mirror 4 Detector 5 Lateral flaw 6 Light source 6a Planar mirror 11 Detector 11a Light receiving element array 12 PD (photodiode) 21 Flaw detection unit 22 Wafer rotation stage 23 Image recognition unit 24 Robot arm 25 Wafer transfer device 26 Normal wafer storage box 27 NG wafer storage box 28 Stand 31, 36, 36a, 36b, ..., 36n Amplifier 32, 37, 37a, 37b, ..., 37n Low-pass filter 33, 38a, 38b, ..., 38n High-pass Filter 34 AD conversion board 35 Data processing device 39 Multiplexer 40 Bias circuit 41 Rotary encoder

Continued on the front page (72) Inventor Nobuo Tomita 585 Tomicho, Funabashi-shi, Chiba Sumitomo Osaka Cement Co., Ltd. (72) Inventor Toshiharu Takei 585 Tomicho, Funabashi-shi, Chiba Sumitomo Osaka Cement Co., Ltd. Inside the research institute (72) Inventor Masahiko Takada 2201 Kamioda, Kota-cho, Kishima-gun, Saga Prefecture Inside Sumitomo Citix Co., Ltd.

Claims (7)

[Claims] 1. An inspected end of an object to be inspected is irradiated with coherent light, and the coherent light is scattered and reflected in a specular direction reflected by a flaw of the inspected end in the vicinity of the inspected end. And detecting and specifying a lateral flaw at the inspected end based on the amount of received light. 2. A method according to claim 1, wherein said coherent light is scattered reflected light other than scattered reflected light in the specular reflection direction reflected by said flaw of said inspected end. An edge flaw inspection method comprising: receiving light at a position different from a light receiving position of scattered reflected light in a direction; detecting and identifying a vertical flaw, a lateral flaw, and an oblique flaw based on the amount of received scattered reflected light. 3. An optical system for irradiating coherent light, a holding device for holding an object to be inspected movably with respect to the optical system, and a coherent light on an inspected end of the object to move relatively. And a second light receiving means for receiving scattered reflected light in the regular reflection direction when the light is irradiated. 4. The apparatus according to claim 3, further comprising a first light receiving means for receiving scattered reflected light when coherent light is applied to an inspected end of the inspected object which moves relatively. Edge scratch inspection device. 5. The edge flaw inspection apparatus according to claim 3, wherein said second light receiving means is a combination of two or more light receiving elements or a light receiving element array combining two or more light receiving elements. . 6. A light receiving element for receiving light in the vicinity of the first focal point of the elliptical mirror when the inspected end is located at or near the first focal point of the elliptical mirror. 6. The end flaw inspection apparatus according to claim 3, wherein: 7. An end flaw inspection apparatus according to claim 3, wherein said holding device is a rotary table for holding a disc-shaped wafer.