Multi-channel visual imaging device and wafer defect detection system

Abstract

The invention relates to the technical field of wafer detection, and discloses a multi-channel visual imaging device and a wafer defect detection system. The device comprises a light source assembly, a differential interference imaging assembly, a dark field imaging assembly, an inclined imaging assembly and a photoluminescence imaging assembly. The light source assembly is used for generating linearly polarized light; the differential interference imaging assembly is used for splitting the linearly polarized light and converging the linearly polarized light to a wafer to be detected, so that two light beams returned from the wafer to be detected interfere with each other and form a corresponding optical image; the dark field imaging assembly is used for collecting light beams deviated and scattered from the to-be-detected wafer and forming corresponding optical images; the inclined imaging assembly is used for irradiating the irradiation light beam to a to-be-detected wafer at a certain angle, collecting the light beam reflected from the to-be-detected wafer and forming a corresponding optical image; and the photoluminescence imaging assembly is used for filtering the light beams generating the fluorescence effect on the wafer to be detected, collecting the filtered light beams and forming a corresponding optical image. According to the embodiment of the invention, the integration level of the visual imaging device can be improved.

Description

Technical Field

[0001] The present application relates to the field of wafer inspection technology, and in particular to a multi-channel visual imaging device and a wafer defect inspection system. Background Art

[0002] Wafer defect detection refers to detecting whether there are defects such as pits, particles, scratches, etc. in the wafer and recording the location and number of defects. It is widely used in wafer manufacturing, pattern wafer lithography and other links.

[0003] In the related technologies, the wafer production process has many steps, the product structure is complex, precise and the manufacturing cost is high. Different types of defects will cause corresponding functional problems in the product. Wafer defect detection not only needs to find the defects on the wafer surface, but also needs to classify the defects and mark the specific location of the defects on the wafer.

[0004] However, in order to adapt to various types of wafer defect detection, the wafer defect detection system needs to be equipped with multiple types of visual imaging devices, and each visual imaging device is respectively equipped with a corresponding light source for illumination, resulting in a complex structure of the wafer defect detection system and not being light enough. Summary of the invention

[0005] The purpose of this application is to provide a multi-channel visual imaging device and a wafer defect detection system, aiming to improve the integration of the visual imaging device to simplify the structure of the wafer defect detection system.

[0006] The present application provides a multi-channel visual imaging device, comprising:

[0007] A light source assembly for generating linearly polarized light;

[0008] A differential interference imaging component, used for splitting the linearly polarized light into two illumination light beams with a phase difference, converging the two illumination light beams onto the wafer to be tested, and causing the two light beams returned from the wafer to be tested to interfere and form a corresponding optical image;

[0009] A dark field imaging component, used for collecting light beams deviated and scattered from the wafer to be tested and forming a corresponding optical image when the two illumination light beams converge to the wafer to be tested;

[0010] an oblique imaging component, used for extracting a light beam from the two irradiation light beams and irradiating the wafer to be tested at a certain angle, collecting the light beam reflected from the wafer to be tested and forming a corresponding optical image; and

[0011] The photoluminescence imaging component is used to filter the light beams generated by the fluorescence effect of the two irradiation light beams on the wafer to be tested, collect the filtered light beams and form corresponding optical images.

[0012] In some embodiments, the dark field imaging component collects the light beam that is deviated and scattered from the wafer to be tested from the side of the transmission path of the two illumination light beams emitted and converged by the differential interference imaging component; the tilt imaging component draws out the light beam from the transmission path of the two illumination light beams emitted by the differential interference imaging component; and the photoluminescence imaging component collects the light beam generated by the fluorescence effect from the transmission path of the light beam that is incident on the differential interference imaging component and returned from the wafer to be tested.

[0013] In some embodiments, the angle between the light output path of the differential interference imaging component and the wafer to be measured is greater than the angle between the light input path of the dark field imaging component and the wafer to be measured, and the angle between the light input path of the dark field imaging component and the wafer to be measured is greater than the angle between the light output path of the tilted imaging component and the wafer to be measured.

[0014] In some embodiments, the light source assembly comprises:

[0015] Laser, used to generate laser light source;

[0016] an optical scribing prism, located in the transmission path of the laser light source, and used for shaping the light spot of the laser light source into a line light spot; and

[0017] The polarizer is located in the transmission path of the shaped laser light source and is used to convert the shaped laser light source into the linearly polarized light.

[0018] In some embodiments, the differential interference imaging component includes:

[0019] A first reflective mirror, located in the transmission path of the linearly polarized light, and used for reflecting the linearly polarized light;

[0020] a differential interference prism, located in the transmission path of the reflected light of the first reflective mirror, for splitting the reflected light of the first reflective mirror into the two irradiation light beams and for merging the two light beams returned from the wafer to be tested;

[0021] a second reflective mirror, located in the transmission path of the illumination light beam, and used for reflecting the illumination light beam;

[0022] A first condensing lens, located in the transmission path of the reflected light of the second transflective mirror, and used for converging the irradiation light beam onto the wafer to be tested;

[0023] A polarizer is located in the transmission path of the two light beams returned from the wafer to be tested and merged, and is used to cause interference between the two light beams returned from the wafer to be tested and merged;

[0024] A second condensing lens, located in the transmission path of the transmitted light of the analyzer, for converging the light beam emitted by the analyzer; and

[0025] The first image acquisition device is located in the transmission path of the light transmitted from the second condensing lens, and is used to receive the light beam emitted from the second condensing lens and form a corresponding optical image.

[0026] In some embodiments, the first image acquisition device, the second condensing lens, the analyzer, the first reflector, the differential interference prism and the second reflector are arranged in sequence along a direction perpendicular to the transmission direction of the linearly polarized light, so that the linearly polarized light can be reflected or refracted by the first reflector, the differential interference prism and the second reflector in sequence to form the two illumination light beams and converge to the wafer to be tested through the first condensing lens, and the two light beams returned from the wafer to be tested can be reflected or refracted by the first condensing lens, the second reflector, the differential interference prism and the first reflector in sequence, and converge to the first image acquisition device through the analyzer and the second condensing lens in sequence.

[0027] In some embodiments, the dark field imaging component comprises:

[0028] a third condenser lens, located at a position deviating from the incident path of the irradiation light beam by a certain angle, and used for converging the light beam deviated and scattered on the wafer to be tested; and

[0029] The second image acquisition device is located in the transmission path of the transmitted light of the third condensing lens, and is used for the light beam emitted from the third condensing lens to form a corresponding optical image.

[0030] In some embodiments, the tilted imaging assembly comprises:

[0031] a third transflective mirror, located in the transmission path of the illumination light beam, and used for reflecting the illumination light beam;

[0032] a fourth transflective mirror, located in a transmission path of the reflected light of the third transflective mirror, and used for reflecting the reflected light of the third transflective mirror and irradiating the reflected light to the wafer to be tested at an angle;

[0033] a fourth condensing lens, located on a reflection path of the light reflected from the fourth reflective mirror, and used for converging the light beam obliquely reflected on the wafer to be tested; and

[0034] The third image acquisition device is located in the transmission path of the transmitted light of the fourth condensing lens, and is used to receive the light beam emitted from the fourth condensing lens and form a corresponding optical image.

[0035] In some embodiments, the photoluminescence imaging assembly comprises:

[0036] A filter device, provided with a plurality of filters having different radiation bands, capable of switching the corresponding filters to the transmission path of the light beam generated by the fluorescence effect, for filtering the light beam generated by the fluorescence effect through the corresponding filters;

[0037] a fifth condensing lens, located in the transmission path of the light emitted by the filter device, and used for converging the light beam emitted after being filtered by the filter device; and

[0038] The fourth image acquisition device is located in the transmission path of the transmitted light of the fifth condensing lens, and is used to receive the light beam emitted from the fifth condensing lens and form a corresponding optical image.

[0039] An embodiment of the present application also provides a wafer defect detection system, including the above-mentioned multi-channel visual imaging device.

[0040] The beneficial effects of the present application are as follows: a light source component and a differential interference imaging component, a dark field imaging component, a tilt imaging component and a photoluminescence imaging component are configured; the differential interference imaging component, the dark field imaging component, the tilt imaging component and the photoluminescence imaging component can all utilize the light source of the light source component to perform corresponding detection on the wafer to be tested and generate corresponding optical images; one light source and four different types of optical detection channels are used to achieve full coverage detection of defects on the wafer to be tested, thereby improving the integration of the visual imaging device and simplifying the structure of the wafer defect detection system. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic diagram of the optical principle of the multi-channel visual imaging device provided in an embodiment of the present application.

[0042] Figure 2 It is a schematic diagram of the optical principle of the differential interference imaging component provided in an embodiment of the present application.

[0043] Figure 3 It is a schematic diagram of the optical principle of the dark field imaging component provided in an embodiment of the present application.

[0044] Figure 4 It is a schematic diagram of the optical principle of the tilted imaging assembly provided in an embodiment of the present application.

[0045] Figure 5 It is a schematic diagram of the optical principle of the photoluminescence imaging component provided in the embodiment of the present application. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0047] It should be noted that the terms "first", "second", "third", "fourth", etc. (if any) in the specification of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a system, product or device that includes a series of circuits is not necessarily limited to those circuits clearly listed, but may include other circuits that are not clearly listed or inherent to these systems, products or devices.

[0048] An embodiment of the present application provides a multi-channel visual imaging device.

[0049] See also Figure 1 In one embodiment, the multi-channel visual imaging device includes a light source component 1, a differential interference imaging component 2, a dark field imaging component 3, a tilt imaging component 4 and a photoluminescence imaging component 5.

[0050] The light source assembly 1 is used to generate linearly polarized light. The light-incoming side of the differential interference imaging assembly 2 is arranged on the transmission path of the linearly polarized light. The differential interference imaging assembly 2 is used to split the linearly polarized light into two irradiation light beams with a phase difference, converge the two irradiation light beams to the wafer to be tested, and cause the two light beams returned from the wafer to be tested to interfere and form a corresponding optical image. The light-incoming side of the dark-field imaging assembly 3 is arranged beside the transmission path of the two light beams returned from the wafer to be tested. The dark-field imaging assembly 3 is used to collect the light beams deviated and scattered from the wafer to be tested when the two irradiation light beams converge to the wafer to be tested and form a corresponding optical image. The light-incoming side of the tilted imaging assembly 4 is arranged on the transmission path of the two irradiation light beams. The light-emitting side of the tilted imaging assembly 4 is symmetrically arranged with the light-incoming side of the tilted imaging assembly 4 along the normal line of the wafer to be tested. The tilted imaging assembly 4 is used to draw out light beams from the two irradiation light beams and irradiate the wafer to be tested at a certain angle, collect the light beams reflected from the wafer to be tested and form a corresponding optical image. On the transmission path of the two light beams returned from the wafer to be tested on the light input side of the photoluminescence imaging component 5, the photoluminescence imaging component 5 is used to filter the light beams generated by the fluorescence effect of the two irradiation light beams on the wafer to be tested, collect the filtered light beams and form a corresponding optical image.

[0051] The multi-channel visual imaging device provided in the embodiment of the present application is used for defect detection of wafers. After the wafer to be tested is placed in the detection station, the light source component 1 generates linear polarized light, the differential interference imaging component 2 splits the linear polarized light into two irradiation beams with a phase difference and converges the two irradiation beams obtained by the splitting to the wafer to be tested, and the irradiation beams converged to the wafer to be tested are reflected by the wafer to be tested and returned to the differential interference imaging component 2, and the differential interference imaging component 2 causes the two beams returned from the wafer to be tested to interfere and form a corresponding optical image, which presents the details of the wafer to be tested with a three-dimensional relief effect, and the details of the wafer to be tested become light and dark contrast enhanced due to the interference of the beams and the change of amplitude. When the differential interference imaging component 2 converges the two irradiation beams obtained by the splitting to the wafer to be tested, the dark field imaging component 3 collects the light beams scattered from the wafer to be tested and forms a corresponding optical image, which is displayed as a visual effect of dark background and bright defects, so as to collect the reflected light of the defects and achieve the effect of dark field detection of defects. When the differential interference imaging component 2 converges the two irradiation light beams obtained by splitting to the wafer to be tested, the light input side of the tilted imaging component 4 draws out a light beam from the two irradiation light beams and irradiates the wafer to be tested at a certain angle, and the light output side of the tilted imaging component 4 collects the light beam reflected from the wafer to be tested and forms a corresponding optical image, which is composed of the reflected light on the upper surface and the reflected light on the lower surface of the wafer to be tested, and can reflect the micropipe defects in the wafer to be tested. When the differential interference imaging component 2 converges the two irradiation light beams obtained by splitting to the wafer to be tested, the photoluminescence imaging component 5 obtains the light beam generated by the fluorescence effect on the wafer to be tested from the transmission path of the two light beams returned from the wafer to be tested, and filters the light beam generated by the fluorescence effect on the wafer to be tested, collects the filtered light beam and forms a corresponding optical image, which displays the defects on the wafer to be tested as bright colors.

[0052] See again Figure 1In a specific embodiment, the dark field imaging component 3 collects the light beam deviated and scattered from the wafer to be tested from the side of the transmission path of the two irradiation light beams emitted and converged by the differential interference imaging component 2, the tilt imaging component 4 leads the light beam from the transmission path of the two irradiation light beams emitted by the differential interference imaging component 2, and the photoluminescence imaging component 5 collects the light beam generated by the fluorescence effect from the transmission path of the light beam incident on the differential interference imaging component 2 and returned from the wafer to be tested. Specifically, the dark field imaging component 3 is arranged beside the light emitting side of the differential interference imaging component 2, and is illuminated beside the transmission path of the two irradiation light beams emitted and converged by the differential interference imaging component 2, so as to collect the light beams deviated and scattered from the wafer to be tested. The light input side of the tilt imaging component 4 is arranged on the transmission path of the differential interference imaging component 2 transmitting the irradiation light beam, so as to lead the light beam from the transmission path of the two irradiation light beams emitted by the differential interference imaging component 2. The light emitting side of the tilt imaging component 4 and the light input side of the tilt imaging component 4 are arranged symmetrically along the normal line of the wafer to be tested, so as to collect the light beams obliquely incident on the wafer to be tested and emitted. The photoluminescence imaging component 5 is arranged on the transmission path of the light beam incident on the differential interference imaging component 2 and returned from the wafer to be tested, so as to collect the light beams generated by the fluorescence effect. The dark field imaging component 3, the tilt imaging component 4 and the photoluminescence imaging component 5 are arranged with the differential interference imaging component 2 as the center, so as to make the multi-channel visual imaging device more compact.

[0053] More specifically, the angle between the light output path of the differential interference imaging component 2 and the wafer to be measured is greater than the angle between the light input path of the dark field imaging component 3 and the wafer to be measured, and the angle between the light input path of the dark field imaging component 3 and the wafer to be measured is greater than the angle between the light output path of the tilted imaging component 4 and the wafer to be measured.

[0054] See again Figure 1 In a specific embodiment, the light source assembly 1 includes a laser 11, an optical scribing prism 12 and a polarizer 13. The laser 11 is used to generate a laser light source. The optical scribing prism 12 is located in the transmission path of the laser light source and is used to shape the spot of the laser light source into a linear spot. The polarizer 13 is located in the transmission path of the shaped laser light source and is used to convert the shaped laser light source into linear polarized light.

[0055] Preferably, the laser 11 is a 355 nm ultraviolet laser, and the optical scribing prism 12 is a Powell prism.

[0056] Specifically, the laser 11 generates a laser light source as an illumination light source and an excitation light source in the optical path. When the laser light source is irradiated to the optical marking prism 12, the optical marking prism 12 shapes the incident laser light source so that the laser beam with a circular spot is shaped into a laser beam with a linear spot. When the shaped laser beam is irradiated to the polarizer 13, the polarizer 13 converts the incident laser beam into linear polarized light.

[0057] Combined with reference Figure 1 and Figure 2 In a specific embodiment, the differential interference imaging assembly 2 includes a first reflector 21, a differential interference prism 22, a second reflector 23, a first condensing lens 24, an analyzer 25, a second condensing lens 26 and a first image acquisition device 27. The first reflector 21 is located in the transmission path of the linearly polarized light, and is used to reflect the linearly polarized light. The differential interference prism 22 is located in the transmission path of the reflected light of the first reflector 21, and is used to split the reflected light of the first reflector 21 into two irradiation light beams and to merge the two light beams returned from the wafer to be measured. The second reflector 23 is located in the transmission path of the irradiation light beam, and is used to reflect the irradiation light beam. The first condensing lens 24 is located in the transmission path of the reflected light of the second reflector 23, and is used to converge the irradiation light beam to the wafer to be measured. The analyzer 25 is located in the transmission path of the two light beams returned from the wafer to be measured and merged, and is used to interfere the two light beams returned from the wafer to be measured and merged. The second condenser lens 26 is located in the transmission path of the transmitted light of the analyzer 25, and is used to converge the light beam emitted by the analyzer 25. The first image acquisition device 27 is located in the transmission path of the transmitted light of the second condenser lens 26, and is used to receive the light beam emitted from the second condenser lens 26 and form a corresponding optical image.

[0058] Preferably, the differential interference prism 22 is a Wollaston prism or a Nomarski prism, and the first condensing lens 24 is an ultraviolet objective lens adapted to an ultraviolet laser.

[0059] Specifically, the first reflective mirror 21 reflects the linearly polarized light generated by the light source assembly 1 to the differential interference lens, and the differential interference lens decomposes the incident linearly polarized light into two illuminating light beams that vibrate perpendicularly to each other and have a certain phase difference (the essence of the illuminating light beam is also linearly polarized light). The two illuminating light beams obtained by the splitting are reflected by the second reflective mirror 23 and then refracted by the first condensing lens 24 and converged to the surface of the wafer to be measured. When the two illuminating light beams are irradiated to the wafer to be measured, the tiny bumps and different refractive indexes at each point on the surface of the wafer to be measured will cause an optical path difference between the two illuminating light beams. The illuminating light beams converged on the wafer to be measured are reflected by the wafer to be measured and returned, and are sequentially passed through the first condensing lens 24. The two light beams are refracted and diverged by 24 and reflected by the second reflective mirror 23, and then enter the differential interference prism 22. After being refracted and reunited by the differential interference prism 22, the two reunited light beams are refracted by the first reflective mirror 21 and then reach the analyzer 25. The analyzer 25 causes the two incident light beams to interfere with each other, so that the details of the wafer to be measured present a three-dimensional relief effect. The details of the wafer to be measured have enhanced light and dark contrast due to the interference of the light beams and the change of amplitude. The two interfering light beams are refracted by the second condensing lens 26 and converged to the light incident side of the first image acquisition device 27. The first image acquisition device 27 receives the light beam emitted from the second condensing lens 26 and forms a corresponding optical image.

[0060] More specifically, the first image acquisition device 27, the second condensing lens 26, the analyzer 25, the first reflector 21, the differential interference prism 22 and the second reflector 23 are arranged in sequence along a direction perpendicular to the transmission direction of the linear polarized light, so that the linear polarized light can be reflected or refracted by the first reflector 21, the differential interference prism 22 and the second reflector 23 in sequence to form two irradiation light beams and converge to the wafer to be tested through the first condensing lens 24, and the two light beams returned from the wafer to be tested can be reflected or refracted by the first condensing lens 24, the second reflector 23, the differential interference prism 22 and the first reflector 21 in sequence and converge to the first image acquisition device 27 through the analyzer 25 and the second condensing lens 26 in sequence.

[0061] Combined with reference Figure 1 and Figure 3 In a specific embodiment, the dark field imaging assembly 3 includes a third condenser lens 31 and a second image acquisition device 32. The third condenser lens 31 is located at a position that deviates from the incident path of the irradiation light beam by a certain angle, and is used to converge the light beam that deviates and scatters on the wafer to be measured. The second image acquisition device 32 is located in the transmission path of the transmitted light of the third condenser lens 31, and is used to collect the light beam emitted from the third condenser lens 31 and form a corresponding optical image.

[0062] Specifically, when the differential interference imaging component 2 converges the two illumination beams obtained by the splitting to the wafer to be tested, the third condensing lens 31 receives the light beam that deviates from the incident path of the illumination beam by a certain angle, and the light beam is refracted by the third condensing lens 31 and converged to the second image acquisition device 32. The second image acquisition device 32 receives the light beam emitted from the third condensing lens 31 and forms a corresponding optical image. The optical image is displayed as a visual effect of dark background and bright defects. When there are uneven defects on the surface of the wafer to be tested, according to the propagation law of light in geometric optics, part of the light will be scattered everywhere. Therefore, the reflected light of the defect can be collected at a certain angle deviating from the incident light, so as to achieve the purpose of dark field defect detection, and the visual effect of dark background and bright defects is displayed in the imaging.

[0063] Combined with reference Figure 1 and Figure 4In a specific embodiment, the oblique imaging assembly 4 includes a third reflective mirror 41, a fourth reflective mirror 42, a fourth condenser lens 43 and a third image acquisition device 44. The third reflective mirror 41 is located in the transmission path of the irradiation light beam, and is used to reflect the irradiation light beam. The fourth reflective mirror 42 is located in the transmission path of the reflected light of the third reflective mirror 41, and is used to reflect the reflected light of the third reflective mirror 41 and obliquely irradiate it to the wafer to be tested. The fourth condenser lens 43 is located in the reflection path of the reflected light of the fourth reflective mirror 42, and is used to converge the light beam obliquely reflected on the wafer to be tested. The third image acquisition device 44 is located in the transmission path of the transmitted light of the fourth condenser lens 43, and is used to receive the light beam emitted from the fourth condenser lens 43 and form a corresponding optical image.

[0064] Specifically, the third reflective mirror 41 reflects a part of the irradiated light beam to the fourth reflective mirror 42, and the fourth reflective mirror 42 reflects the incident light beam to the wafer to be tested at a certain angle. The light beam irradiated to the wafer to be tested at a certain angle is reflected by the wafer to be tested and then irradiated to the fourth condenser lens 43, refracted by the fourth condenser lens 43 and converged to the light-incoming side of the third image acquisition device 44. The third image acquisition device 44 receives the light beam emitted from the fourth condenser lens 43 and forms a corresponding optical image. The optical image is composed of the reflected light on the upper surface and the reflected light on the lower surface of the wafer to be tested, and can reflect the micropipe defects in the wafer to be tested. Among them, the micropipe defect is a defect that penetrates the wafer at a certain angle. When light is irradiated to different positions on the surface of the wafer to be tested at a certain angle, reflected light on the upper surface and reflected light on the lower surface are formed. The position where the micropipe defect exists will be blocked to varying degrees, which appears as a dark spot in the imaging. The third image acquisition device 44 collects the light intensity of the two beams of reflected light, and the formed optical image presents an inverted V shape at different angles, which can effectively distinguish micropipe defects from other surface defects that appear as points.

[0065] Combined with reference Figure 1 and Figure 5 In a specific embodiment, the photoluminescent imaging component 5 includes a filter device 51, a fifth condenser lens 52 and a fourth image acquisition device 53. The filter device 51 is provided with a plurality of filters having different radiation bands, respectively, and the corresponding filters can be switched to the transmission path of the light beam generated by the fluorescence effect, so as to filter the light beam generated by the fluorescence effect through the corresponding filter. The fifth condenser lens 52 is located in the transmission path of the light output of the filter device 51, and is used to converge the light beam emitted after being filtered by the filter device 51. The fourth image acquisition device 53 is located in the transmission path of the transmitted light output of the fifth condenser lens 52, and is used to receive the light beam emitted from the fifth condenser lens 52 and form a corresponding optical image.

[0066] Specifically, the light input side of the filter device 51 is arranged on the transmission path of the light beam generated by the fluorescence effect. The filter device 51 filters the light beam generated by the fluorescence effect through the corresponding filter, so that the fluorescence photons caused by the defects of the corresponding wafer to be tested can pass through. By switching the filters of different radiation bands, the fluorescence photons caused by the defects of different wafers to be tested can pass through. The fourth image acquisition device 53 receives the light beam emitted from the filter and forms a corresponding optical image.

[0067] An embodiment of the present application also provides a wafer defect detection system.

[0068] The wafer defect detection system includes the above-mentioned multi-channel visual imaging device. The specific structure of the multi-channel visual imaging device refers to the above-mentioned embodiment. Since the wafer defect detection system provided by the embodiment of the present application adopts all the technical solutions of all the above-mentioned embodiments, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here one by one.

[0069] In summary, the multi-channel visual imaging device and wafer defect detection system provided in the embodiments of the present application are configured with a light source component and a differential interference imaging component, a dark field imaging component, a tilted imaging component and a photoluminescence imaging component. The differential interference imaging component, the dark field imaging component, the tilted imaging component and the photoluminescence imaging component can all use the light source of the light source component to perform corresponding detection on the wafer to be tested and generate corresponding optical images. By using one light source and four different types of optical detection channels, full coverage detection of defects on the wafer to be tested can be achieved, the integration of the visual imaging device can be improved, and the structure of the wafer defect detection system can be simplified.

[0070] It should be understood that in the present application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0071] The preferred embodiments of the present invention are described above with reference to the accompanying drawings, but the scope of the rights of the present invention is not limited thereto. Any modification, equivalent substitution and improvement made by a person skilled in the art without departing from the scope and essence of the present invention should be within the scope of the rights of the present invention.

Claims

1. A multi-channel visual imaging device, characterized in that: include: A light source assembly for generating linearly polarized light; A differential interference imaging component, used for splitting the linearly polarized light into two illumination light beams with a phase difference, converging the two illumination light beams onto the wafer to be tested, and causing the two light beams returned from the wafer to be tested to interfere and form a corresponding optical image; A dark field imaging component, used for collecting light beams deviated and scattered from the wafer to be tested and forming a corresponding optical image when the two illumination light beams converge to the wafer to be tested; an oblique imaging component, used for extracting a light beam from the two irradiation light beams and irradiating the wafer to be tested at a certain angle, collecting the light beam reflected from the wafer to be tested and forming a corresponding optical image; and The photoluminescence imaging component is used to filter the light beams generated by the fluorescence effect of the two irradiation light beams on the wafer to be tested, collect the filtered light beams and form corresponding optical images.

2. The multi-channel visual imaging device according to claim 1, characterized in that: The dark field imaging component collects the light beam deviated and scattered from the wafer to be tested from the side of the transmission path of the two irradiation light beams emitted and converged by the differential interference imaging component; the tilt imaging component draws out the light beam from the transmission path of the two irradiation light beams emitted by the differential interference imaging component; the photoluminescence imaging component collects the light beam generated by the fluorescence effect from the transmission path of the light beam incident on the differential interference imaging component and returned from the wafer to be tested.

3. The multi-channel visual imaging device according to claim 1, characterized in that: The angle between the light output path of the differential interference imaging component and the wafer to be tested is greater than the angle between the light input path of the dark field imaging component and the wafer to be tested, and the angle between the light input path of the dark field imaging component and the wafer to be tested is greater than the angle between the light output path of the tilted imaging component and the wafer to be tested.

4. The multi-channel visual imaging device according to any one of claims 1 to 3, characterized in that: The light source assembly comprises: Laser, used to generate laser light source; an optical scribing prism, located in the transmission path of the laser light source, and used for shaping the light spot of the laser light source into a line light spot; and The polarizer is located in the transmission path of the shaped laser light source and is used to convert the shaped laser light source into the linearly polarized light.

5. The multi-channel visual imaging device according to any one of claims 1 to 3, characterized in that: The differential interference imaging component comprises: A first reflective mirror, located in the transmission path of the linearly polarized light, and used for reflecting the linearly polarized light; a differential interference prism, located in the transmission path of the reflected light of the first reflective mirror, for splitting the reflected light of the first reflective mirror into the two irradiation light beams and for merging the two light beams returned from the wafer to be tested; a second reflective mirror, located in the transmission path of the illumination light beam, and used for reflecting the illumination light beam; A first condensing lens, located in the transmission path of the reflected light of the second transflective mirror, and used for converging the irradiation light beam onto the wafer to be tested; A polarizer is located in the transmission path of the two light beams returned from the wafer to be tested and merged, and is used to cause interference between the two light beams returned from the wafer to be tested and merged; A second condensing lens, located in the transmission path of the transmitted light of the analyzer, for converging the light beam emitted by the analyzer; and The first image acquisition device is located in the transmission path of the light transmitted from the second condensing lens, and is used to receive the light beam emitted from the second condensing lens and form a corresponding optical image.

6. The multi-channel visual imaging device according to claim 5, characterized in that: The first image acquisition device, the second condensing lens, the analyzer, the first reflector, the differential interference prism and the second reflector are arranged in sequence along a direction perpendicular to the transmission direction of the linearly polarized light, so that the linearly polarized light can be reflected or refracted by the first reflector, the differential interference prism and the second reflector in sequence to form the two irradiation light beams and converge to the wafer to be measured through the first condensing lens, and the two light beams returned from the wafer to be measured can be reflected or refracted by the first condensing lens, the second reflector, the differential interference prism and the first reflector in sequence, and converge to the first image acquisition device through the analyzer and the second condensing lens in sequence.

7. The multi-channel visual imaging device according to any one of claims 1 to 3, characterized in that: The dark field imaging component comprises: a third condenser lens, located at a position deviating from the incident path of the irradiation light beam by a certain angle, and used for converging the light beam deviated and scattered on the wafer to be tested; and The second image acquisition device is located in the transmission path of the transmitted light of the third condensing lens, and is used for the light beam emitted from the third condensing lens to form a corresponding optical image.

8. The multi-channel visual imaging device according to any one of claims 1 to 3, characterized in that: The tilt imaging assembly comprises: a third transflective mirror, located in the transmission path of the illumination light beam, and used for reflecting the illumination light beam; a fourth transflective mirror, located in a transmission path of the reflected light of the third transflective mirror, and used for reflecting the reflected light of the third transflective mirror and irradiating the reflected light to the wafer to be tested at an angle; a fourth condensing lens, located on a reflection path of the light reflected from the fourth reflective mirror, and used for converging the light beam obliquely reflected on the wafer to be tested; and The third image acquisition device is located in the transmission path of the transmitted light of the fourth condensing lens, and is used to receive the light beam emitted from the fourth condensing lens and form a corresponding optical image.

9. The multi-channel visual imaging device according to any one of claims 1 to 3, characterized in that: The photoluminescence imaging component comprises: A filter device, provided with a plurality of filters having different radiation bands, capable of switching the corresponding filters to the transmission path of the light beam generated by the fluorescence effect, for filtering the light beam generated by the fluorescence effect through the corresponding filters; a fifth condensing lens, located in the transmission path of the light emitted by the filter device, and used for converging the light beam emitted after being filtered by the filter device; and The fourth image acquisition device is located in the transmission path of the transmitted light of the fifth condensing lens, and is used to receive the light beam emitted from the fifth condensing lens and form a corresponding optical image.

10. A wafer defect detection system, characterized in that: A multi-channel visual imaging device comprising any one of claims 1 to 9.

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