Defect detection device and shading assembly setting device

Abstract

The invention discloses a defect detection device and a shading assembly setting device. The defect detection device comprises a bright-field light source, a dark-field light source, an objective lens, a tube lens, a bright-field camera, a dark-field camera and a shading assembly; the bright-field light source emits a first illumination light beam, the first part of first illumination light is transmitted by the objective lens and then enters the surface of a sample to be detected, the sample to be detected is reflected to form a bright-field signal light beam, and the bright-field signal light beam is transmitted by the objective lens and the tube lens in sequence and then enters the bright-field camera; the second part of the first illumination light beam is reflected by the lens surface in the objective lens to form stray light, and the stray light is shielded by the shading assembly; the dark field light source outputs a second illumination light beam, the second illumination light beam enters the surface of the to-be-detected sample, the to-be-detected sample is scattered to form a dark field signal light beam, and the dark field signal light beam enters the dark field camera after being sequentially transmitted by the objective lens and the tube lens. The influence of stray light on dark field detection is reduced, and the effect of eliminating stray light on the periphery of the exit pupil plane of the objective lens and generated by reflection of lenses in the objective lens is achieved.

Description

Technical Field

[0001] This invention relates to the field of optical inspection technology, and in particular to a defect detection device and a light-shielding component setting device. Background Technology

[0002] Unavoidable contamination and manufacturing errors during semiconductor chip processing are significant causes of chip failure. Performing wafer defect detection during semiconductor manufacturing can improve yield.

[0003] Among existing wafer defect detection methods, optical imaging-based methods are the most commonly used. To improve the detection sensitivity of defect detection devices, a dark-field detection device is usually configured within a bright-field detection device to construct a bright-dark-field defect detection system. To eliminate stray light interference with imaging, an illumination modulation component is typically used to suppress reflections of illumination light around the exit pupil of the objective lens.

[0004] Devices that simultaneously scan bright and dark fields not only need to prevent crosstalk through reasonable field-of-view offset design, but also face the impact of stray light from bright field illumination on the dark field, resulting in a brighter dark field background and a reduced signal-to-noise ratio. In addition to stray light reflected from the outer periphery of the objective lens exit pupil, much stray light also originates from reflections by the internal lenses of the objective lens. Methods that use illumination modulation components to suppress reflections of illumination light from the outer periphery of the objective lens exit pupil cannot suppress stray light reflected from the internal lenses of the objective lens. Summary of the Invention

[0005] This invention provides a defect detection device and a light-shielding component setting device. The device sets a light-shielding component to block stray light generated by bright field illumination, thereby eliminating stray light and reducing the impact of stray light on dark field detection.

[0006] In a first aspect, the present invention provides a defect detection device, comprising a bright field light source, a dark field light source, an objective lens, a tube lens, a bright field camera, a dark field camera, and a light-shielding component;

[0007] The bright field light source is used to emit the first illumination beam. The first part of the first illumination beam is transmitted through the objective lens and then incident on the surface of the sample to be tested. The sample to be tested reflects the light to form a bright field signal beam. The bright field signal beam is transmitted through the objective lens and the tube lens in sequence and then incident on the bright field camera. The second part of the first illumination beam is reflected by the lens surface inside the objective lens to form stray light. The stray light is blocked by the light shielding component.

[0008] The dark field light source is used to output a second illumination beam. The second illumination beam is incident on the surface of the sample to be tested. The sample to be tested scatters the beam to form a dark field signal beam. The dark field signal beam passes through the objective lens and the tube lens in sequence before being incident on the dark field camera.

[0009] Optionally, the defect detection device may further include a relay lens group located in the optical path between the objective lens and the tube lens.

[0010] Optionally, the light-shielding component is located on the focal plane of the relay lens group on the side away from the objective lens, and the second part of the first illumination beam reflected by the lens surface inside the objective lens is converged to the light-shielding component after being transmitted through the relay lens group.

[0011] Optionally, the defect detection device further includes a semi-transparent and semi-reflective mirror, which is located in the optical path between the objective lens and the tube lens. The first illumination beam emitted from the bright field light source is reflected by the semi-transparent and semi-reflective mirror and then incident on the objective lens.

[0012] Optionally, the objective lens includes an aperture stop and at least two lenses, the aperture stop being located on the side of the lenses away from the sample to be tested.

[0013] Optionally, the aperture of the aperture stop is smaller than the aperture of the lens.

[0014] Optionally, the first illumination beam reflected from the two surfaces of each lens forms a second portion of the first illumination beam.

[0015] Optionally, the light-shielding component includes a light-shielding plate.

[0016] Secondly, the present invention provides a light-shielding component setting device for determining the size and position of the light-shielding component in the above-mentioned defect detection device. The light-shielding component setting device includes an illumination source, a first objective lens, a first tube lens, a dark-field imaging plane aperture, a second tube lens, and a camera. The parameters of the first objective lens are the same as those of the objective lens in the defect detection device, the parameters of the first tube lens are the same as those of the tube lens in the defect detection device, and the parameters of the dark-field imaging plane aperture are the same as those of the dark-field camera in the defect detection device. The first tube lens and the second tube lens are symmetrically distributed and form a 4F system.

[0017] The illumination beam emitted from the illumination source is incident on the first objective lens. After being reflected by the lens surface inside the first objective lens, transmitted through the first tube mirror, transmitted through the dark field imaging surface aperture, and transmitted through the second tube mirror, it is incident on the camera. The size of the light-shielding component is determined according to the size of the camera's light spot, and the position of the light-shielding component is determined according to the 4F system.

[0018] Optionally, the light-shielding assembly device further includes a first relay lens group, which is located between the first objective lens and the first tube endoscope.

[0019] The defect detection device provided in this invention utilizes bright-field imaging, which is suitable for scenes with obvious surface features and high contrast, and dark-field imaging, which has high sensitivity to small particles, scratches, and changes in surface roughness. By using dark-field scattered light imaging, it compensates for the detection defects of bright-field imaging for weak contrast samples, improves the sensitivity of wafer defect detection, and places a light-shielding component at an appropriate position in the imaging optical path to block stray light generated by bright-field illumination, thereby eliminating stray light interference and reducing the impact of stray light on dark-field detection. At the same time, the setting of the light-shielding component can effectively suppress stray light reflected from the internal lenses of the objective lens, thereby eliminating stray light generated by reflection from the periphery of the objective lens exit pupil and stray light generated by reflection from the internal lenses of the objective lens.

[0020] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of a defect detection device provided in an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of another defect detection device provided in an embodiment of the present invention;

[0024] Figure 3 This is a schematic diagram of the objective lens structure of a defect detection device provided in an embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of a light-shielding component setting device provided in an embodiment of the present invention.

[0026] In this embodiment of the invention, the reference numerals and corresponding feature names are as follows:

[0027] 1-Objective lens, 2-Tube lens, 3-Dark field camera, 4-Bright field camera, 5-Semi-transparent mirror, 6-Sample to be tested, 7-Dark field light source, 8-Bright field light source, 9-Light shielding assembly, 10-Lens, 11-Relay lens group, 12-Entry pupil plane of objective lens, 13-Aperture stop, 14-Illumination light source, 15-First objective lens, 16-First relay lens group, 17-First tube lens, 18-Second tube lens, 19-Camera, 20-Relay pupil plane, 21-Dark field imaging plane aperture stop, 22-First illumination beam of the first part, 23-Second illumination beam, 24-First illumination beam of the second part, 25-Stray light. Detailed Implementation

[0028] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0029] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0030] Figure 1 This is a schematic diagram of a defect detection device according to an embodiment of the present invention. This embodiment of the present invention is applicable to situations where stray light generated by bright-field illumination affects dark-field detection in wafer bright-dark-field defect detection.

[0031] like Figure 1As shown, the defect detection device provided in this embodiment of the invention includes a bright-field light source 8, a dark-field light source 7, an objective lens 1, a tube lens 2, a bright-field camera 4, a dark-field camera 3, and a light-shielding component 9. The bright-field light source 8 emits a first illumination beam 22. A first portion of the first illumination beam 22 is transmitted through the objective lens 1 and then incident on the surface of the sample 6 to be tested. The sample 6 reflects the beam to form a bright-field signal beam. The bright-field signal beam is transmitted through the objective lens 1 and the tube lens 2 sequentially before being incident on the bright-field camera 4. A second portion of the first illumination beam 24 is reflected by the lens 10 inside the objective lens 1 to form stray light 25, which is blocked by the light-shielding component 9. The dark-field light source 4 outputs a second illumination beam 23. The second illumination beam 23 is incident on the surface of the sample 6 to be tested. The sample 6 scatters the beam to form a dark-field signal beam. The dark-field signal beam is transmitted through the objective lens 1 and the tube lens 2 sequentially before being incident on the dark-field camera 3.

[0032] In this embodiment, the bright-field light source 8 can be understood as light directly entering the objective lens 1, passing through the objective lens 1 to illuminate the sample 6 under test, and the transmitted light from the sample 6 enters the objective lens 1 for imaging, emitting the first illumination beam. The dark-field light source 7 can be understood as light not directly entering the objective lens 1, but illuminating the sample 6 under test at an angle. After the light is scattered by the microstructures on the surface of the sample 6, the scattered light can enter the objective lens 1 for imaging, emitting the second illumination beam 23. The objective lens 1 can be understood as the optical lens closest to the sample 6 under test in the microscope, directly responsible for collecting the light reflected or scattered by the sample 6. The tube lens 2 is an optical lens located between the objective lens 1 and the imaging device, which can be used in conjunction with the objective lens to correct the aberrations of the objective lens, ensure the clarity and accuracy of the image, and guide the light to the imaging device to complete the final image. The bright-field camera 4 can be understood as a device that uses bright-field illumination and captures light differences through a camera sensor to form an image. The dark-field camera 3 can be understood as a device that uses dark-field illumination and captures scattered light to form an image. The light-shielding component 9 can be understood as a device that blocks light. For example, the light-shielding component 9 can be a baffle, but this embodiment of the present invention does not limit it.

[0033] Specifically, the bright-field light source 8 emits a first illumination beam, which is divided into two parts. The first part, the first illumination beam 22, is transmitted through the objective lens 1 and then incident on the surface of the sample 6 under test. After being reflected by the sample 6, it forms a bright-field signal beam. The bright-field signal beam is transmitted through the objective lens 1 and the tube lens 2 in sequence and then incident on the bright-field camera 4. The second part, the first illumination beam 24, is reflected by the surface of the lens 10 inside the objective lens 1 to form bright-field illumination stray light 25, which is then incident on the light-shielding component 9. The bright-field illumination stray light 25 is blocked by the light-shielding component 9, preventing it from entering the dark-field camera 3. The dark-field light source 7 outputs a second illumination beam 23, which is incident on the surface of the sample 6 under test. After being scattered by the sample 6, it forms a dark-field signal beam. The dark-field signal beam is transmitted through the objective lens 1 and the tube lens 2 in sequence and then incident on the dark-field camera 3.

[0034] The defect detection device provided in this embodiment of the invention utilizes bright-field imaging, which is suitable for scenes with obvious surface features and high contrast, and dark-field imaging, which has high sensitivity to minute particles, scratches, and surface roughness changes of the sample 6 under test. By using dark-field scattered light imaging, the detection defects of bright-field imaging for weak contrast samples are compensated, thereby improving the sensitivity of wafer defect detection. By setting a light-shielding component 9 in the defect detection device, stray light 25 generated by the reflection of the bright-field illumination beam through the lens 10 in the objective lens 1 is blocked, thus solving the problem that stray light 25 affects the dark-field detection accuracy in bright and dark-field defect detection. This achieves the effect of reducing the influence of stray light 25 and improving the accuracy and speed of sample detection.

[0035] Figure 2 This is a schematic diagram of another defect detection device provided in an embodiment of the present invention. Figure 2 As shown, the defect detection device also includes a relay lens group 11, which is located in the optical path between the objective lens 1 and the tube lens 2.

[0036] Optionally, the light-shielding component 9 is located on the focal plane of the relay lens group 11 on the side away from the objective lens 1. The second part of the first illumination beam 24, after being reflected by the surface of the lens 10 inside the objective lens 1, is focused onto the light-shielding component 9 after being transmitted through the relay lens group 11.

[0037] Optional, continue to refer to Figure 1 or Figure 2 The defect detection device also includes a semi-transparent mirror 5, which is located in the optical path between the objective lens 1 and the tube lens 2. The first illumination beam emitted from the bright field light source 8 is reflected by the semi-transparent mirror 5 and then incident on the objective lens 1.

[0038] In this embodiment, the relay lens group 11 can be understood as an optical component composed of multiple lenses, used to transmit optical images or light paths, maintain the clarity, position or orientation of the image, extend the light path, change the direction of the light path, or adapt to different optical components. The semi-transparent and semi-reflective mirror 5 can be understood as an optical element capable of transmitting part of the incident light and reflecting part of it, used to split the light beam into two parts.

[0039] Specifically, when the pupil plane is inside the objective lens 1, placing a light-shielding component at the entrance pupil plane 12 of the objective lens would cause some operational inconvenience. In this case, a relay lens group 11 is placed in the optical path between the objective lens 1 and the tube lens 2. The relay lens group 11 generates a relay pupil plane, and a light-shielding component 9 can be placed at the position of the relay pupil plane. A semi-transparent mirror 5 is placed in the optical path between the objective lens 1 and the tube lens 2. After the first illumination beam emitted from the bright field light source 8, the first illumination beam is split into two parts by the semi-transparent mirror 5. The first part, the first illumination beam 22, is transmitted through the objective lens 1 and then incident on the surface of the sample 6 under test. After reflection by the sample 6, it forms a bright field signal beam. The second part, the first illumination beam 24, is reflected by the surface of the lens 10 inside the objective lens 1 to form bright field illumination stray light that enters the relay lens group 11. The light-shielding component 9 is located on the focal plane of the relay lens group 11 on the side away from the objective lens 1. The bright field illumination stray light 25 formed by the second part of the first illumination beam 24 after being reflected by the surface of the lens 10 inside the objective lens 1 is converged to the light-shielding component 9 after being transmitted through the relay lens group 11.

[0040] For example, the bright field light source 8 emits a first illumination beam. After passing through the semi-transparent mirror 5 in the optical path between the objective lens 1 and the tube lens 2, the first illumination beam is split into two parts. The first part, the first illumination beam 22, is transmitted through the objective lens 1 and then incident on the surface of the sample 6 to be tested. After being reflected by the sample 6, it forms a bright field signal beam. The second part, the first illumination beam 24, is reflected by the surface of the lens 10 in the objective lens 1 to form bright field illumination stray light, which is then incident on the relay lens group 11 between the objective lens 1 and the tube lens 2. The bright field illumination stray light 25 formed by the second part, the first illumination beam 24, is transmitted through the relay lens group 11 and then converges to the light shielding component 9, where it is blocked. At this time, the stray light 25 cannot pass through the tube lens 2 and be captured by the dark field camera 3 because it is blocked.

[0041] The defect detection device provided in this embodiment of the invention generates a relay pupil surface by setting a semi-transparent mirror 5 and a relay lens group 11. A light-shielding component 9 is set at the relay pupil surface to block the stray light 25 generated by the reflection of bright field illumination light through the lens 10 in the objective lens 1, cutting off the propagation path of the stray light 25 and preventing it from reaching the image plane, thus eliminating the influence of stray light 25 on dark field detection. At the same time, the setting of the relay lens group solves the problem that it is inconvenient to add a light-shielding component 9 at the entrance pupil surface 12 of the objective lens when the pupil surface is inside the objective lens. This achieves the elimination of stray light 25 generated by reflection from the outer periphery of the exit pupil surface of the objective lens and the reflection of internal lenses of the objective lens 1, thus achieving the effect of suppressing the stray light 25 generated by reflection from the internal lenses of the objective lens 1.

[0042] Optionally, the light-shielding component 9 includes a light-shielding plate.

[0043] Figure 3 This is a schematic diagram of the objective lens structure of a defect detection device provided in an embodiment of the present invention. Figure 3 As shown, the objective lens 1 includes an aperture stop 13 and at least two lenses, with the aperture stop 13 located on the side of the lens 10 away from the sample 6 to be tested.

[0044] In this embodiment, the aperture stop 13 can be understood as an optical element used to limit the range of light beams, adjust the luminous flux, or control the imaging quality. It is typically composed of an opening or light-blocking edge with a certain shape. Only light from a specific area or angle is allowed to pass through. For example, the aperture stop 13 can be an aperture stop, but this embodiment of the invention does not impose any limitations on this. The lens 10 can be understood as an optical element made of a transparent material. Light passing through the lens 10 will be refracted, changing its propagation direction and forming different imaging effects.

[0045] Specifically, an aperture 13 is set on the side of the lens 10 in the objective lens 1 away from the sample 6. The aperture of the aperture 13 is smaller than the aperture of the lens 10. Under the premise of satisfying the energy requirements of bright field illumination, the aperture of the aperture 13 is as small as possible. Only part of the bright field illumination stray light 25 reflected by the lens 10 from the second part of the first illumination beam 24 can pass through the aperture of the aperture 13 and reach the relay lens group 11.

[0046] For example, the bright-field light source 8 emits a first illumination beam. After passing through the semi-transparent mirror 5 in the optical path between the objective lens 1 and the tube lens 2, the first illumination beam is split into two parts. The first part, the first illumination beam 22, is transmitted through the objective lens 1 and then incident on the surface of the sample 6 under test. After being reflected by the sample 6, it forms a bright-field signal beam. The second part, the first illumination beam 24, is reflected by the surface of the lens 10 inside the objective lens 1 to form bright-field illumination stray light 25. A portion of the reflected bright-field illumination stray light 25 that passes through the aperture of the aperture 13 will enter the relay lens group 11 between the objective lens 1 and the tube lens 2. The other portion of the stray light 25 that does not pass through the aperture of the aperture 13 will not enter the relay lens group 11. The bright-field illumination stray light 25 that passes through the relay lens group 11 is transmitted and then converges to the light-shielding component 9, where it is blocked. At this time, the stray light 25 cannot pass through the tube lens 2 and be captured by the dark-field camera 3 because it is blocked.

[0047] In this embodiment of the invention, by setting an aperture stop 13 in the objective lens 1 with a aperture smaller than that of the lens 10, some of the stray light 25 formed by the bright-field illumination after the second portion of the first illumination beam 24 is reflected by the lens 10 is filtered by the aperture stop 13 before entering the relay lens group 11. Only the stray light 25 that passes through the aperture stop 13 can continue to pass through the relay lens group 11 and reach the light-shielding component 9 to be blocked. This embodiment of the invention establishes a "filtering" and "blocking" structure in the entire optical path, which has a double-layer blocking effect on the bright-field illumination stray light 25, thereby achieving the effect of minimizing the stray light 25 and reducing its impact on dark-field detection.

[0048] Optional, for reference Figure 3 The aperture of aperture 13 is smaller than that of lens 10.

[0049] This setting can reduce the aperture of the stray light 25 reflected by the bright field illumination, so that some of the stray light 25 cannot pass through the light-transmitting aperture of the aperture 13 and is filtered out, thereby improving the effect of eliminating stray light 25.

[0050] Optionally, the first illumination beam reflected from the two surfaces of each lens forms a second portion of the first illumination beam 24.

[0051] Figure 4 This is a schematic diagram of a light-shielding component setting device provided in an embodiment of the present invention. This embodiment optimizes and expands upon the above-described optional implementation methods. A light-shielding component setting device is provided, which realizes the above-described optional implementation methods by setting the position, size, and structure of the light-shielding component 9.

[0052] like Figure 4As shown, the light-shielding component setting device is used to determine the size and position of the light-shielding component 9 in any of the above-mentioned defect detection devices. The light-shielding component setting device includes an illumination source 14, a first objective lens 15, a first tube lens 17, a dark-field imaging aperture 12, a second tube lens 18, and a camera 19. The first objective lens 15 has the same parameters as the objective lens 1 in the defect detection device in the above embodiment, the first tube lens 17 has the same parameters as the tube lens 2 in the defect detection device in the above embodiment, and the dark-field imaging aperture 21 has the same parameters as the dark-field camera 3 in the defect detection device in the above embodiment. The first tube lens 17 and the second tube lens 18 are symmetrically distributed and form a 4F system. The illumination beam emitted from the illumination source 14 is incident on the first objective lens 15, and after reflection from the surface of the lens 10 inside the first objective lens 15, transmission through the first tube lens 17, transmission through the dark-field imaging aperture 21, and transmission through the second tube lens 18, it is incident on the camera 19. The size of the light-shielding component 9 is determined according to the size of the light spot of the camera 19, and the position of the light-shielding component 9 is determined according to the 4F system.

[0053] In this embodiment of the invention, the dark field imaging aperture 21 can be understood as an aperture element used to achieve a dark field illumination effect, used to block direct light and only allow scattered light or oblique light to enter the imaging system. The 4F system can be understood as an optical system that can filter, enhance, or suppress the spatial frequency components of the input light field.

[0054] Specifically, the dark field camera 3 of the defect detection device is replaced with a dark field imaging aperture 21, with the aperture's transmission position corresponding to the target surface position of the dark field camera 3. The first tube mirror 17 is placed at a distance F in front of the dark field imaging aperture 21, and the second tube mirror 18 is placed at a distance F behind the dark field imaging aperture 21. The second tube mirror 18 has the same parameters as the first tube mirror 17, but is an inverted version of the first tube mirror 17, forming a symmetrical distribution with it. The second tube mirror 18 and the first tube mirror 17 form a 4F system. The image plane of the second tube mirror 18 is conjugate to the pupil plane of the first tube mirror 17, and the images formed on the two planes are of equal size but opposite in direction. The position and size of stray light on the relay pupil plane 20 are obtained by rotational symmetry of the position and size of the light spot of the camera 19 on the image plane of the second tube mirror 18, thereby obtaining the position and size of the light-shielding component 9.

[0055] In this embodiment of the invention, a first tube lens 17, a second tube lens 18, and a dark-field imaging plane aperture 21 are arranged so that the first tube lens 17 and the second tube lens 18 are symmetrically distributed, forming a 4F system. The position and size of stray light 25 on the relay pupil plane 20 are obtained by rotationally symmetrically determining the position and size of the light-shielding component 9 based on the position and size of the stray light 25 on the relay pupil plane 20. This method of arranging the position and size of the light-shielding component 9 according to the position and size of the stray light 25 on the relay pupil plane 20 can accurately lock the spatial range of the stray light 25, achieving the effect of only blocking useless stray light rays, reducing the obstruction of the effective beam of normal imaging, effectively eliminating the influence of stray light 25 without affecting normal imaging detection.

[0056] Optional, continue to refer to Figure 4 The light-shielding assembly device also includes a first relay lens group 16, which is located between the first objective lens 15 and the first tube lens 17.

[0057] This configuration allows the relay pupil surface 20 generated by the first relay lens group 16 to provide a precise working surface for the setting of the light-shielding component 9, solving the problem that it is inconvenient to add the light-shielding component 9 at the pupil surface position when the pupil surface is inside the objective lens, thus achieving a simple and convenient operation.

[0058] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A defect detection apparatus characterized by comprising: The device comprises a bright field light source, a dark field light source, an objective lens, a tube lens, a bright field camera, a dark field camera and a light shielding assembly; The bright field light source is used to emit a first illumination light beam, a first part of the first illumination light beam is transmitted through the objective lens and then is incident on the surface of a sample to be measured, the sample to be measured reflects to form a bright field signal light beam, the bright field signal light beam is transmitted through the objective lens and then is transmitted through the tube lens and is incident on the bright field camera, a second part of the first illumination light beam is reflected by the lens surface in the objective lens to form stray light, and the stray light is shielded by the light shielding assembly; The dark field light source is used to output a second illumination light beam, the second illumination light beam is incident on the surface of the sample to be measured, the sample to be measured scatters to form a dark field signal light beam, and the dark field signal light beam is transmitted through the objective lens and then is transmitted through the tube lens and is incident on the dark field camera.

2. The defect detection apparatus according to claim 1, characterized by The device further comprises a relay lens group, which is located on the optical path between the objective lens and the tube lens.

3. The defect detection apparatus according to claim 2, characterized by The light shielding assembly is located on the focal plane of the side of the relay lens group away from the objective lens, and the second part of the first illumination light beam reflected by the lens surface in the objective lens is transmitted through the relay lens group and then converges on the light shielding assembly.

4. The defect detection apparatus according to claim 1, characterized by The device further comprises a half-transmission half-reflection mirror, which is located on the optical path between the objective lens and the tube lens, and the first illumination light beam emitted by the bright field light source is reflected by the half-transmission half-reflection mirror and then is incident on the objective lens.

5. The defect detection apparatus according to claim 1, characterized by The objective lens comprises a diaphragm and at least two lenses, and the diaphragm is located on the side of the lens away from the sample to be measured.

6. The defect detection apparatus according to claim 5, characterized by The clear aperture of the diaphragm is smaller than the clear aperture of the lens.

7. The defect detection apparatus according to claim 5, wherein The first illumination light beam reflected by the two surfaces of each lens forms the second part of the first illumination light beam.

8. The defect detection apparatus according to claim 1, characterized by The light shielding assembly comprises a light shielding plate.

9. A device for setting a light-shielding assembly, characterized by comprising: The device for determining the size and position of the light shielding assembly in the defect detection device of any one of claims 1-8 comprises an illumination light source, a first objective lens, a first tube lens, a dark field imaging plane diaphragm, a second tube lens and a camera, the first objective lens has the same parameters as the objective lens in the defect detection device of any one of claims 1-8, the first tube lens has the same parameters as the tube lens in the defect detection device of any one of claims 1-8, the dark field imaging plane diaphragm has the same parameters as the dark field camera in the defect detection device of any one of claims 1-8, the first tube lens and the second tube lens are symmetrically distributed and form a 4F system; The illumination light beam emitted by the illumination light source is incident on the first objective lens, is reflected by the lens surface in the first objective lens, is transmitted through the first tube lens, is transmitted through the dark field imaging plane diaphragm, is transmitted through the second tube lens and is incident on the camera, the size of the light shielding assembly is determined according to the spot size of the camera, and the position of the light shielding assembly is determined according to the 4F system.

10. The device of claim 9, wherein The device further comprises a first relay lens group, which is located between the first objective lens and the first tube lens.

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