Wafer defect detection apparatus
Patent Information
- Application Number
- CN202522560186.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-02
- Publication Date
- 2026-11-03
- Estimated Expiration
- 2035-12-02
AI Technical Summary
Traditional methods of manually inspecting semiconductor wafers for defects suffer from poor accuracy, inconsistent results, and are time-consuming and labor-intensive.
By employing a combination of a rotatable stage, optical components, and detectors, the rotatable stage drives the wafer to rotate, and the optical components emit and receive laser beams. Combined with the movement of the moving components, automated defect detection of the wafer is achieved.
It enables rapid, accurate, and comprehensive detection of defects in semiconductor wafers, improving detection efficiency and accuracy, especially with significant results in identifying minute defects.
Smart Images
Figure CN224933909U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of semiconductor wafer inspection technology, and in particular to a wafer defect detection device. Background Technology
[0002] Traditionally, defect detection on semiconductor wafers (such as silicon carbide wafers) relies on visual inspection by testers under strong light. This method has significant limitations, especially when dealing with minute or hidden defects. Visual inspection is susceptible to fatigue and misjudgment, potentially leading to incorrect defect counts. For large-area wafers, this manual defect counting method is extremely time-consuming and labor-intensive. Furthermore, each tester may have different judgment criteria, resulting in significant discrepancies in the inspection results for the same wafer by different testers. Overall, traditional manual defect inspection methods for semiconductor wafers suffer from poor accuracy, inconsistent inspection results, and are time-consuming and labor-intensive. Utility Model Content
[0003] To address the aforementioned technical problems, this application provides a wafer defect detection device to overcome the limitations of manual wafer defect detection and improve the detection speed, efficiency, and accuracy of semiconductor wafer defects.
[0004] To achieve the above objectives, this application provides the following technical solution:
[0005] A wafer defect detection device, comprising:
[0006] A rotatable stage is used to hold the wafer to be tested and can drive the wafer to be tested to rotate.
[0007] An optical component is used to emit an incident laser beam, focus the incident laser beam onto the wafer under test, and receive the reflected laser beam after being reflected by the wafer under test.
[0008] A movable component is used to move the optical component along a first direction, the first direction being parallel to the surface of the wafer to be tested;
[0009] A detector is used to acquire defect information of the wafer under test based on the reflected laser beam.
[0010] Optionally, the wafer to be tested is vacuum-adsorbed onto the rotatable stage.
[0011] Optionally, the optical component includes:
[0012] A laser emitter for emitting the incident laser beam;
[0013] A first optical component is used to focus the incident laser beam emitted by the laser emitter onto the wafer to be tested;
[0014] The second optical component is used to receive the reflected laser beam after it has been reflected by the wafer under test, and to transmit the reflected laser beam to the detector.
[0015] Optionally, the first optical component includes a polarizer, a first reflector, a filter, and a first focusing lens arranged along the optical path transmission direction.
[0016] Optionally, the second optical component includes a second focusing mirror, a second reflecting mirror, a convex lens, and a pinhole arranged along the optical path transmission direction.
[0017] Optionally, the second optical component further includes a beam splitter located behind the aperture along the optical path transmission direction.
[0018] Optionally, the detector includes a reflected light detector and a four-quadrant position detector;
[0019] The reflected photodetector is used to identify whether there is a defect and the type of defect at a corresponding position on the wafer to be inspected based on the reflected laser beam;
[0020] The four-quadrant position detector is used to determine the location and shape of defects on the wafer to be inspected based on the reflected laser beam.
[0021] Optionally, the optical component specifically focuses the incident laser beam onto the wafer to be tested at a preset angle, the preset angle being in the range of 40°-70°, including the endpoint value.
[0022] Optionally, the wavelength of the incident laser beam is in the range of 750nm-780nm, including the endpoint values.
[0023] Optionally, the wafer to be tested is a silicon carbide wafer.
[0024] Compared with existing technologies, the above technical solution has the following advantages:
[0025] The wafer defect detection apparatus provided in this application includes a rotatable stage, an optical component, a moving component, and a detector. When performing defect detection on a wafer, the wafer is placed on the rotatable stage. An incident laser beam is emitted by the optical component and focused onto a specific location on the wafer. The reflected laser beam is received after being reflected by the wafer and then transmitted to the detector. The detector identifies the defect information at the corresponding location on the wafer based on the reflected laser beam. Furthermore, during the detection process, the rotatable stage rotates the wafer, causing the incident laser beam emitted by the optical component to remain on the wafer at various points. At a certain radius, the detector can scan at least one ring of the wafer to be inspected, obtaining the reflected laser beams at at least one ring of the wafer's radius. Simultaneously, the moving component can drive the optical component to move along a first direction parallel to the surface of the wafer. For example, the moving component can drive the optical component to move the incident position of the incident laser beam on the wafer from the edge of the wafer to the center of the wafer in a stepwise manner along a diameter direction. In this way, the reflected laser beams at at least one ring of each radius of the wafer can be obtained, i.e., the entire surface of the wafer, and the detector can then acquire defect information of the entire surface of the wafer.
[0026] Therefore, firstly, the wafer defect detection device provided in this application emits a laser beam through an optical component to focus and scan the wafer to be detected, and obtains the defect information of the wafer to be detected based on the laser beam reflected by the wafer to be detected through a detector, thereby realizing the automated and rapid detection of defects in the wafer to be detected, overcoming the limitations of existing manual wafer defect detection, and improving the efficiency and accuracy of semiconductor wafer defect detection.
[0027] Secondly, in the process of defect detection of the wafer under test, the wafer defect detection device provided in this application can use a rotatable stage to drive the wafer under test to rotate, so that whenever the incident laser beam emitted by the optical component stops at a position of a certain radius on the wafer under test, the reflected laser beam at least one circle of that radius of the wafer under test can be obtained. In addition, the optical component is driven to move step by step along the first direction by the moving component, so that the incident position of the incident laser beam on the wafer under test only needs to move by a radius distance, for example, to obtain the reflected laser beam of the entire surface of the wafer under test, thereby further improving the speed and efficiency of semiconductor wafer defect detection.
[0028] Third, in the process of defect detection of the wafer to be inspected, the wafer defect detection device provided in this application uses a moving component to drive the optical component to move step by step along the first direction, and can also make the incident laser beam and the reflected laser beam move within the pre-adjusted focal plane, thereby ensuring the consistency of laser scanning focus at different radii and positions of the wafer to be inspected, avoiding detection errors caused by inconsistent focus of laser scanning at different positions of the wafer to be inspected, and further improving the precision and accuracy of semiconductor wafer defect detection.
[0029] Fourth, the wafer defect detection device provided in this application adopts the above-mentioned combination of wafer rotation and laser step scanning, which can continuously obtain reflected laser beams at different positions of the same radius and different radii of the wafer under test. This allows for subsequent analysis of the dynamic changes of the obtained reflected laser beams, providing more detailed and comprehensive wafer defect detection data. This is beneficial for extracting more defect feature information and further improving the comprehensiveness and accuracy of semiconductor wafer defect detection, especially for the identification of micro-defects (such as encapsulation defects in silicon carbide wafers). Attached Figure Description
[0030] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0031] Figure 1 This is a schematic diagram of the structure of a wafer defect detection device provided in an embodiment of this application;
[0032] Figure 2 This is a schematic diagram of the optical path transmission structure of a wafer defect detection device provided in an embodiment of this application;
[0033] Figure 3 The wafer defect detection device provided in this application provides a partial surface defect distribution map output after detecting encapsulation defects in a silicon carbide wafer;
[0034] Figure 4 The wafer defect detection device provided in this application detects encapsulation defects in a silicon carbide wafer and outputs another local surface defect distribution map.
[0035] Explanation of reference numerals in the attached figures:
[0036] Rotatable stage 100; wafer to be tested 110; incident laser beam S1; reflected laser beam S2; first direction X; optical assembly 200; laser emitter 210; first optical assembly 220; second optical assembly 230; polarizer 221; first reflector 222; filter 223; first focusing lens 224; second focusing lens 231; second reflector 232; convex lens 233; pinhole 234; beam splitter 235; moving assembly 300; moving track 310; support 320; detector 400; reflected light detector 410; four-quadrant position detector 420. Detailed Implementation
[0037] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0038] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms are interchangeable where appropriate; this is merely a way of distinguishing objects with the same attributes in the embodiments of this application. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, so that a process, method, system, product, or apparatus that comprises a series of elements is not necessarily limited to those elements but may include other elements not explicitly listed or inherent to those processes, methods, products, or apparatuses.
[0039] Secondly, this application provides a detailed description in conjunction with schematic diagrams. When detailing the embodiments of this application, for ease of explanation, the accompanying drawings illustrating the device structure may be partially enlarged, not to scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of this application. In addition, actual fabrication should include three-dimensional spatial dimensions of length, width, and depth.
[0040] As described in the background section, traditional methods of manually inspecting semiconductor wafers for defects suffer from poor inspection accuracy, poor inspection consistency, and are time-consuming and labor-intensive.
[0041] In view of this, embodiments of this application provide a wafer defect detection device. Figure 1 This paper shows a schematic diagram of the structure of a wafer defect detection device provided in an embodiment of this application, as shown below. Figure 1As shown, the wafer defect detection device includes a rotatable stage 100, an optical component 200, a moving component 300, and a detector 400. The rotatable stage 100 is used to carry the wafer 110 to be inspected and can drive the wafer 110 to rotate. The optical component 200 is used to emit an incident laser beam S1, focus the incident laser beam S1 onto the wafer 110 to be inspected, and receive the reflected laser beam S2 after being reflected by the wafer 110 to be inspected. The moving component 300 is used to drive the optical component 200 to move along a first direction X, the first direction X being parallel to the surface of the wafer 110 to be inspected. The detector 400 is used to acquire defect information of the wafer 110 to be inspected based on the reflected laser beam S2.
[0042] Understandably, when performing defect detection on the wafer 110, the wafer 110 is placed on a rotatable stage 100, and an incident laser beam S1 is emitted by an optical component 200. The incident laser beam S1 is focused onto a position of the wafer 110 and a reflected laser beam S2 is received after being reflected by the wafer 110. The reflected laser beam S2 is then transmitted to a detector 400 so that the detector 400 can identify the defect information at the corresponding position of the wafer 110 based on the reflected laser beam S2.
[0043] Furthermore, during the testing process, the rotatable stage 100 drives the wafer 110 under test to rotate, so that the incident laser beam S1 emitted by the optical component 200 stops at a position with a certain radius on the wafer 110 under test (e.g., Figure 1 At position A), the positions around the radius of the chip 110 to be detected can be determined (e.g., ...). Figure 1 The detector 400 scans the circumference L1 of the wafer 110 to obtain the reflected laser beam at least one ring position of the radius of the wafer 110 to be inspected. Then, the detector 400 can obtain the defect information of the wafer 110 to be inspected at one ring position of the radius based on the collected reflected laser beam at at least one ring position of the radius of the wafer 110 to be inspected.
[0044] Meanwhile, the moving component 300 can drive the optical component 200 to move along a first direction X parallel to the surface of the wafer to be inspected. For example, the moving component 300 can drive the optical component 200 so that the incident position of the incident laser beam S1 on the wafer to be inspected 110 moves step by step from the edge of the wafer to be inspected 110 along a radial direction to the center of the wafer to be inspected 110. In this way, the reflected laser beams of the entire surface of the wafer to be inspected 110 can be obtained at the positions of each radius of the wafer to be inspected 110. Then, the detector 400 can obtain the defect information of the entire surface of the wafer to be inspected 110 based on the collected reflected laser beams of the entire surface of the wafer to be inspected 110.
[0045] It is also understandable that before defect detection of the wafer 110, the optical component 200 can be adjusted so that the incident laser beam S1 emitted by the optical component 200 is focused onto the wafer 110 at a certain incident angle, and the reflected laser beam S2 after being reflected by the wafer 110 can be received by the optical component 200. After focusing, during the defect detection of the wafer 110, the moving component 300 drives the optical component 200 to move along the first direction X. The incident position of the incident laser beam S1 emitted by the optical component 200 on the wafer 110 also moves along the first direction X, and can move within the focused focal plane. Furthermore, during the process of the moving component 300 driving the optical component 200 to move along the first direction X and the rotatable stage 100 driving the wafer 110 to rotate, the positional relationship between the incident laser beam S1 and the reflected laser beam S2 remains unchanged, and the reflected laser beam S2 can always be received by the optical component 200.
[0046] During defect detection of the wafer 110 under test, the moving component 300 drives the optical component 200 to move along the first direction X. This allows the incident laser beam S1 to move its incident position on the wafer 110 along a radial direction of the wafer 110, for example, from the edge of the wafer 110 to its center, or from its center to its edge. In this case, the first direction X is parallel to the radial direction of the wafer 110. However, this application does not limit whether the first direction X is parallel to the radial direction of the wafer 110. It is conceivable that the first direction X could also be parallel to the surface of the wafer 110 but not parallel to its radial direction. Since the rotating stage 100 can rotate the wafer 110 during the detection process, the reflected laser beam from a local area of the wafer 110 can also be collected as needed.
[0047] Therefore, firstly, the wafer defect detection device provided in this application embodiment emits a laser beam through the optical component 200 to focus and scan the wafer 110 to be detected, and obtains the defect information of the wafer 110 to be detected based on the laser beam reflected by the detector 400, thereby realizing the automated and rapid detection of defects in the wafer to be detected, overcoming the limitations of existing manual wafer defect detection, and improving the efficiency and accuracy of semiconductor wafer defect detection.
[0048] Secondly, in the process of defect detection of the wafer 110 under test, the wafer defect detection device provided in this application embodiment can use the rotatable stage 100 to drive the wafer 110 under test to rotate, so that whenever the incident laser beam S1 emitted by the optical component 200 stops at a position of a certain radius on the wafer 110 under test, the reflected laser beam of at least one circle of that radius of the wafer 110 under test can be obtained. In conjunction with the use of the moving component 300 to drive the optical component 200 to move step by step along the first direction X, the incident position of the incident laser beam on the wafer 110 under test only needs to move by a radius distance to obtain the reflected laser beam of the entire surface of the wafer 110 under test, thereby further improving the speed and efficiency of semiconductor wafer defect detection.
[0049] Third, in the process of defect detection of the wafer 110 to be inspected, the wafer defect detection device provided in this application uses the moving component 300 to drive the optical component 200 to move step by step along the first direction X, and can also make the incident laser beam S1 and the reflected laser beam S2 move within the pre-adjusted focal plane, thereby ensuring the consistency of laser scanning focus at different radii and positions of the wafer 110 to be inspected, avoiding detection errors caused by inconsistent focus of laser scanning at different positions of the wafer 110 to be inspected, and further improving the precision and accuracy of semiconductor wafer defect detection.
[0050] Fourth, the wafer defect detection device provided in this application adopts the above-mentioned method of combining the rotation of the wafer 110 to be detected with laser step scanning, which can continuously obtain reflected laser beams S2 at different positions of the same radius and different radii of the wafer 110 to be detected. This allows for subsequent analysis of the dynamic changes of the obtained reflected laser beams S2, providing more detailed and comprehensive wafer defect detection data. This is beneficial for extracting more defect feature information and further improving the comprehensiveness and accuracy of semiconductor wafer defect detection, especially for the identification of small defects (such as encapsulation defects in silicon carbide wafers).
[0051] In this embodiment, the rotatable stage 100 drives the rotation of the wafer 110 to be tested, and the moving component 300 drives the optical component 200 to move along the first direction X. The coordination and control of the two can be manually controlled or controlled by a controller, depending on the situation.
[0052] In this embodiment, optionally, the rotatable stage 100 can drive the wafer 110 to be tested to rotate uniformly at high speed; alternatively, the rotatable stage 100 can also drive the wafer 110 to be tested to rotate intermittently when the moving component 300 drives the optical component 200 to stop in stages.
[0053] Optionally, in some embodiments of this application, such as Figure 1As shown, the wafer 110 to be tested is vacuum-adsorbed onto the rotatable stage 100. With this configuration, the wafer 110 is evenly adsorbed onto the rotatable stage 100 with uniform force on its entire surface, preventing damage to the wafer 110 due to uneven force. Furthermore, the vacuum adsorption between the wafer 110 and the rotatable stage 100 is relatively strong, avoiding separation when the rotatable stage 100 drives the wafer 110 to rotate at high speed.
[0054] Optionally, in some embodiments of this application, such as Figure 2 As shown, Figure 2 A schematic diagram of the optical path transmission structure of a wafer defect detection device provided in an embodiment of this application is shown. As can be seen, the optical component 200 includes a laser emitter 210, a first optical component 220, and a second optical component 230. The laser emitter 210 is used to emit an incident laser beam S1. The first optical component 220 is used to focus the incident laser beam S1 emitted by the laser emitter 210 onto the wafer 110 to be inspected. The second optical component 230 is used to receive the reflected laser beam S2 after being reflected by the wafer 110 to be inspected, and to transmit the reflected laser beam S2 to the detector 400.
[0055] Further optional, such as Figure 2 As shown, the first optical component 220 includes a polarizer 221, a first reflector 222, a filter 223, and a first focusing lens 224 arranged along the optical path transmission direction. That is, the incident laser beam S1 emitted by the laser emitter 210 can pass through the polarizer 221, the first reflector 222, the filter 223, and the first focusing lens 224 in sequence before being focused onto the wafer 110 to be tested. Among them, the polarizer 221 allows laser beams with a specific polarization direction to pass through; the first reflector 222 can change the transmission direction of the laser beam, which is beneficial to reducing the size of the first optical component 220; the filter 223 can filter out light of excess wavelengths, so that the incident laser beam illuminating the wafer 110 to be tested is a laser beam of a certain wavelength or a certain range of wavelengths; the first focusing lens 224 is an objective lens, and focusing can be achieved by adjusting the first focusing lens 224.
[0056] like Figure 2As shown, the second optical component 230 includes a second focusing mirror 231, a second reflecting mirror 232, a convex lens 233, and a pinhole 234 arranged along the optical path transmission direction. That is, the reflected laser beam S2 after being reflected by the chip 110 to be detected can be transmitted to the detector 400 after passing through the second focusing mirror 231, the second reflecting mirror 232, the convex lens 233, and the pinhole 234 in sequence. Among them, the second focusing mirror 231 focuses the reflected laser beam; the second reflecting mirror 232 can change the transmission direction of the laser beam, which is beneficial to reducing the size of the second optical component 230; the convex lens 233 and the pinhole 234 cooperate to amplify the focused reflected laser beam.
[0057] Considering that multiple detectors may be used to identify defect information of the wafer 110 under inspection based on the collected reflected laser beam S2, further alternatively, such as Figure 2 As shown, the second optical component 230 may further include a beam splitter 235 located behind the aperture 234 along the optical path transmission direction. The beam splitter 235 is used to split the amplified reflected laser beam S2 into at least two beams for transmission to different detectors.
[0058] Optionally, in some embodiments of this application, such as Figure 1 and Figure 2 As shown, the detector 400 includes a reflected light detector 410 and a four-quadrant position detector 420; wherein, the reflected light detector 410 is used to identify whether there is a defect and the type of defect at the corresponding position of the wafer 110 to be inspected based on the reflected laser beam S2; the four-quadrant position detector 420 is used to determine the position and shape of the defect on the wafer to be inspected based on the reflected laser beam.
[0059] Specifically, the reflected light detector 410 is mainly responsible for measuring the intensity, wavelength and other information of the reflected laser beam S2. It can provide the intensity information of the reflected laser beam over the entire range of the wafer 110 under test, so as to identify abnormal reflected light intensity by analyzing the intensity changes of the reflected laser beam S2, and then infer the possible defect location and nature in the wafer 110 under test.
[0060] The four-quadrant position detector 420 can accurately measure the angular change of the reflected laser beam. It divides the collected reflected laser beam into four quadrants and infers the offset direction and magnitude of the reflected laser beam by the light intensity difference of the reflected laser beam in each quadrant. It can accurately locate the offset and deformation of the reflected laser beam, thereby helping to determine the specific location of the defect in the wafer 110 to be inspected. The four-quadrant position detector 420 can provide high-precision positioning information. Through the fine detection of position changes, it can provide more detailed information such as the shape, size and depth of the defect. It is especially suitable for detecting small defects and analyzing the small offset of the beam (such as the angular change caused by the change of reflected light during scanning).
[0061] Suppose there is a tiny crack on a silicon carbide wafer. A reflective photodetector may detect a change in the intensity of the reflected laser beam, indicating an anomaly at the corresponding location on the silicon carbide wafer. However, the location and shape of the crack may be very small, and the reflective photodetector can only locate it roughly. In this case, a four-quadrant position detector can more accurately locate the crack by measuring the angular deviation of the reflected laser beam, and even help analyze the direction and depth of the crack.
[0062] Alternatively, detector 400 may include only reflective light detector 410, or only four-quadrant position detector 420, or other detectors, depending on the specific circumstances.
[0063] Based on any of the above embodiments, optionally, in some embodiments of this application, the optical component 200 specifically focuses the incident laser beam S1 onto the wafer 110 to be inspected at a preset angle. The preset angle can be understood as the angle between the incident laser beam S1 and the normal direction of the wafer 110 to be inspected. The preset angle can be in the range of 40°-70°, including the endpoint value. This setting can, on the one hand, increase the interaction between the incident laser beam S1 and the surface of the wafer 110 to be inspected, especially when detecting microcracks and surface defects of the wafer 110 to be inspected, because surface defects are highly sensitive to changes in the angle of incident light, thus providing more directional information. On the other hand, it can also make the reflected laser beam S2 after being reflected by the wafer 110 to be inspected more regular and the signal stronger. The correlation between the changes in the reflected laser beam S2 and the defects is more intuitive, thereby further improving the accuracy and precision of wafer defect detection.
[0064] Based on any of the above embodiments, optionally, in some embodiments of this application, the wavelength range of the incident laser beam S1 is 750nm-780nm, including the endpoint value. That is, the wavelength of the incident laser beam S1 can be relatively long. It is understood that a longer wavelength laser beam is less affected by surface impurities, contamination layers and complex reflection paths of the wafer to be tested, and the laser signal has stronger penetration ability. Therefore, a longer wavelength laser beam is more suitable for defect detection when the wafer surface is relatively rough or has an oxide layer.
[0065] Based on any of the above embodiments, optionally, in some embodiments of this application, such as Figure 1 As shown, the moving component 300 may include a moving track 310 and a support 320. The support 320 is used to connect the optical component 200 and the moving track 310, so that the support 320 can drive the optical component 200 to move on the moving track 310. However, this application does not limit the specific form of the moving component 300, as long as it can drive the optical component 200 to move.
[0066] In various embodiments of this application, the wafer to be tested 110 can be a silicon carbide wafer, and the wafer defect detection device can detect the encapsulation defects of the silicon carbide wafer, but this application does not limit this.
[0067] In various embodiments of this application, such as Figure 1 As shown, the wafer defect detection device can be placed in a vacuum space to perform defect detection on the wafer 110 to be inspected.
[0068] Optionally, the wafer defect detection apparatus provided in this application embodiment may further include a processor, which processes the defect information of the wafer 110 to be detected obtained by the detector 400 and outputs a surface defect distribution map of the wafer 110 to be detected. Figure 3 and Figure 4 The illustration shows a local surface defect distribution map output by the wafer defect detection device provided in this application after detecting encapsulation defects in a silicon carbide wafer.
[0069] The various parts of this manual are described in a combination of parallel and progressive methods. Each part focuses on the differences between the other parts, and the same or similar parts can be referred to each other.
[0070] The features described above regarding the disclosed embodiments can be substituted or combined with each other to enable those skilled in the art to implement or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A wafer defect detection device, characterized in that, include: A rotatable stage is used to hold the wafer to be tested and can drive the wafer to be tested to rotate. An optical component is used to emit an incident laser beam, focus the incident laser beam onto the wafer under test, and receive the reflected laser beam after being reflected by the wafer under test. A movable component is used to move the optical component along a first direction, the first direction being parallel to the surface of the wafer to be tested; A detector is used to acquire defect information of the wafer under test based on the reflected laser beam.
2. The wafer defect detection device according to claim 1, characterized in that, The wafer to be tested is vacuum-adsorbed onto the rotatable stage.
3. The wafer defect detection device according to claim 1, characterized in that, The optical components include: A laser emitter for emitting the incident laser beam; A first optical component is used to focus the incident laser beam emitted by the laser emitter onto the wafer to be tested; The second optical component is used to receive the reflected laser beam after it has been reflected by the wafer under test, and to transmit the reflected laser beam to the detector.
4. The wafer defect detection device according to claim 3, characterized in that, The first optical component includes a polarizer, a first reflector, a filter, and a first focusing lens arranged along the optical path transmission direction.
5. The wafer defect detection device according to claim 3, characterized in that, The second optical component includes a second focusing mirror, a second reflecting mirror, a convex lens, and a pinhole, all arranged along the optical path transmission direction.
6. The wafer defect detection device according to claim 5, characterized in that, The second optical component also includes a beam splitter located behind the aperture along the optical path transmission direction.
7. The wafer defect detection device according to claim 1, characterized in that, The detector includes a reflected light detector and a four-quadrant position detector; The reflected photodetector is used to identify whether there is a defect and the type of defect at a corresponding position on the wafer to be inspected based on the reflected laser beam; The four-quadrant position detector is used to determine the location and shape of defects on the wafer to be inspected based on the reflected laser beam.
8. The wafer defect detection apparatus according to any one of claims 1-7, characterized in that, Specifically, the optical component focuses the incident laser beam onto the wafer to be tested at a preset angle, the preset angle being in the range of 40°-70°, including the endpoint value.
9. The wafer defect detection apparatus according to any one of claims 1-7, characterized in that, The wavelength range of the incident laser beam is 750nm-780nm, including the endpoint values.
10. The wafer defect detection apparatus according to any one of claims 1-7, characterized in that, The wafer to be tested is a silicon carbide wafer.