Wafer defect detection method, device and storage medium

Abstract

The application discloses a wafer defect detection method, equipment and a storage medium. The wafer defect detection method comprises the following steps: obtaining a relationship between a reflection surface height and a collection module height; the relationship between the reflection surface height and the collection module height is a relationship between a height coordinate of a wafer to be measured and a height coordinate of reflected light irradiated to a reflected light signal collection module; outputting a pre-scanning signal to a motion module and receiving pre-scanning coordinate information; determining fine scanning coordinate information according to the pre-scanning coordinate information and the relationship between the reflection surface height and the collection module height; and adjusting a motion path of the motion module according to the fine scanning coordinate information and generating wafer defect information according to the obtained scattered light. The technical scheme of the application avoids the problems of inaccurate wafer defect detection size and positioning when the wafer to be measured is in a non-flat state, and improves the accuracy of wafer defect detection.

Description

Technical Field

[0001] This invention relates to the field of wafer defect detection technology, and in particular to a wafer defect detection method, device and storage medium. Background Technology

[0002] Various defects are inevitably generated during semiconductor manufacturing. In order to detect defects on wafers, existing technologies generally use wafer defect detection devices to identify the defect structure on the wafer surface.

[0003] In wafer defect detection equipment, the original light generated by a laser is shaped into a probe light that illuminates the wafer surface. When this probe light hits a defect, it scatters, and the defect is identified by collecting this scattered light. The scattering from the defect can be considered a point light source; the collection system gathers the scattered light within a certain scattering angle range and focuses it onto the detector. During defect detection, the contact point between the probe light and the wafer must always be located at the front focal plane of the defect signal collection system. Simultaneously, to ensure the defect signal strength and stability, the wafer surface must always be at the focal point of the probe light. However, due to factors such as bending, warping, and thickness variations on the wafer surface, the wafer is not in an ideally flat state, resulting in low accuracy in wafer defect detection. Summary of the Invention

[0004] This invention provides a wafer defect detection method, device, and storage medium to solve the problem of low accuracy in wafer defect detection caused by the non-flatness of the wafer in the prior art.

[0005] According to a first aspect of the present invention, a wafer defect detection method is provided, characterized in that it is applied in a wafer inspection device; the wafer inspection device includes: an optical module, a motion module, a scattered light signal acquisition module, a reflected light signal acquisition module, and a control module;

[0006] The optical module emits probe light to the wafer under test; the motion module carries the wafer under test and moves it; the scattered light signal acquisition module receives the scattered light from the wafer under test; and the reflected light signal acquisition module receives the reflected light from the wafer under test.

[0007] The control module is communicatively connected to the motion module, the scattered light signal acquisition module, and the reflected light signal acquisition module, respectively.

[0008] Wafer defect detection methods include:

[0009] Obtain the relationship between the height of the reflective surface and the height of the acquisition module; wherein, the relationship between the height of the reflective surface and the height of the acquisition module is the relationship between the height coordinates of the wafer under test and the height coordinates of the reflected light illuminating the reflected light signal acquisition module;

[0010] Output the pre-scan signal to the motion module and receive the pre-scan coordinate information;

[0011] The fine scan coordinate information is determined based on the pre-scan coordinate information and the relationship between the height of the reflective surface and the height of the acquisition module.

[0012] The motion path of the motion module is adjusted based on the fine scan coordinate information, and wafer defect information is generated based on the acquired scattered light.

[0013] Optionally, the motion module includes a vertical motion motor and a height calibration column;

[0014] The relationship between the height of the reflective surface and the height of the acquisition module is obtained, including:

[0015] Obtain the coordinates of the reference origin The reference origin coordinates are the height coordinates of the reflected light illuminating the reflected light signal acquisition module when the reflective surface of the height calibration column is located at the focal plane of the scattered light signal acquisition module.

[0016] The vertical motion motor is controlled to move, thereby moving the height calibration column and obtaining the moving distance dy and calibration height coordinate z of the height calibration column; where the calibration height coordinate z is the height coordinate of the reflected light illuminating the reflected light signal acquisition module corresponding to the moving distance dy.

[0017] Based on the coordinates of the reference origin The relationship between the height of the reflector and the height of the acquisition module is determined by the moving distance dy and the calibration height coordinate z.

[0018] Optionally, the relationship between the height of the reflective surface and the height of the acquisition module is as follows: ;

[0019] Where y is the height of the reflecting surface; a is a constant.

[0020] Optionally, the fine scan coordinate information is determined based on the pre-scan coordinate information and the relationship between the height of the reflective surface and the height of the acquisition module, including:

[0021] Based on pre-scan coordinate information The relationship between the height of the reflective surface and the height of the acquisition module determines the fine scan coordinate information. ;

[0022] Where r is the distance from the point where the probe light is incident on the wafer under test to the center of the wafer under test; The angle between the line connecting the point where the probe light is incident on the wafer under test to the center of the wafer under test and the polar axis.

[0023] Optionally, the motion path of the motion module can be adjusted based on the fine scan coordinate information, including:

[0024] Based on the fine scan coordinate information Determine each detection point The corresponding adjustment height is -y;

[0025] According to each testing point The corresponding height-y adjustment controls the motion path of the motion module.

[0026] Optionally, receive pre-scan coordinate information, including:

[0027] Receive height information from the reflected light signal acquisition module;

[0028] The pre-scan coordinate information is determined based on the motion path and height information of the motion module.

[0029] Optionally, after generating wafer defect information based on the acquired scattered light, the process further includes:

[0030] The location and size of wafer defects are determined based on wafer defect information.

[0031] According to a second aspect of the present invention, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement a wafer defect detection method.

[0032] According to a third aspect of the present invention, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements a wafer defect detection method.

[0033] The technical solution of this invention obtains pre-scanning coordinate information by acquiring the relationship between the height of the reflective surface and the height of the acquisition module in advance and performing pre-scanning. The fine scan coordinate information is determined by combining the pre-scanning coordinate information and the relationship between the height of the reflective surface and the height of the acquisition module. Based on the fine scan coordinate information, the motion path of the motion module is adjusted in real time during the fine scan process. This avoids the problem of inaccurate detection size and positioning of wafer defects when the wafer under test is in a non-flat state, and improves the accuracy of wafer defect detection.

[0034] 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

[0035] 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.

[0036] Figure 1This is a connection diagram of a wafer inspection device according to an embodiment of the present invention;

[0037] Figure 2 This is a schematic diagram of the structure of a motion module according to an embodiment of the present invention;

[0038] Figure 3 This is a schematic diagram of reflected light collection provided in an embodiment of the present invention;

[0039] Figure 4 This is a schematic diagram of the first type of scattered light acquisition provided in the embodiments of the present invention;

[0040] Figure 5 This is a schematic diagram of the second type of scattered light collection provided in the embodiments of the present invention;

[0041] Figure 6 This is a flowchart of a first wafer inspection method provided according to an embodiment of the present invention;

[0042] Figure 7 This is a schematic diagram of a wafer motion trajectory provided by an embodiment of the present invention;

[0043] Figure 8 This is a flowchart of a second wafer inspection method provided according to an embodiment of the present invention;

[0044] Figure 9 This is a flowchart of the third wafer inspection method provided according to an embodiment of the present invention;

[0045] Figure 10 This is a flowchart of the fourth wafer inspection method provided according to an embodiment of the present invention;

[0046] Figure 11 This is a flowchart of the fifth wafer inspection method provided according to an embodiment of the present invention;

[0047] Figure 12 This is a flowchart of the sixth wafer inspection method provided in the embodiments of the present invention;

[0048] Figure 13 This is a schematic diagram of an electronic device structure applied to a wafer defect detection method according to an embodiment of the present invention. Detailed Implementation

[0049] 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 of the present invention. 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.

[0050] 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.

[0051] Figure 1 This is a connection diagram of a wafer inspection device provided according to an embodiment of the present invention. Figure 1 As shown, the wafer inspection device includes: an optical module 1, a motion module 2, a scattered light signal acquisition module 3, a reflected light signal acquisition module 4, and a control module 5;

[0052] Optical module 1 is used to emit probe light to the wafer under test 6; motion module 2 is used to carry the wafer under test 6 and drive the wafer under test 6 to move; scattered light signal acquisition module 3 is used to receive the scattered light of the wafer under test 6; reflected light signal acquisition module 4 is used to receive the reflected light of the wafer under test 6.

[0053] The control module 5 is communicatively connected to the motion module 2, the scattered light signal acquisition module 3, and the reflected light signal acquisition module 4, respectively.

[0054] The optical module 1 can consist of a laser and a beam shaping system. The laser can be used to generate the original collimated light; the beam shaping system shapes the original collimated light into focused light.

[0055] Figure 2 This is a structural schematic diagram of a motion module provided according to an embodiment of the present invention, combined with... Figure 1 and Figure 2 As shown, the motion module 2 may include a wafer chuck 21 and a motion module 22; the wafer chuck 21 can be used to carry and fix the wafer 6 to be tested; the motion module 22 can drive the wafer 6 to be tested to move in three dimensions along the horizontal direction, the vertical direction and the rotation direction.

[0056] Figure 3 This is a schematic diagram of reflected light collection provided in an embodiment of the present invention, combined with... Figure 1 and Figure 3As shown, the reflected light signal acquisition module 4 can be composed of a reflected light shaping system 41 and a spot position detector 42; the reflected light shaping system 41 collimates and focuses the reflected diverging light and then transmits it to the spot position detector 42; the spot position detector 42 can be a linear array charge-coupled device to detect changes in the position of the reflected light.

[0057] The scattered light signal acquisition module 3 is used to receive the scattered light from the wafer 6 under test. Figure 4 This is a schematic diagram of the first type of scattered light acquisition provided in the embodiments of the present invention, combined with... Figure 1 and Figure 4 As shown, it can be composed of a scattered light collector 31, an aperture 32, and a photomultiplier tube 33. The scattered light collector 31 can be used to collect scattered light within a certain range and focus it onto the aperture 32. The aperture 32 only blocks other stray light by focusing the scattered light. The photomultiplier tube 33 can be used to detect the scattered light signal and convert it into an electrical signal input to the control module 5. Specifically, the probe light is incident on the defect location on the surface of the wafer 6 under test and is scattered at the defect location. After being collected and focused by the scattered signal collector, it passes through the aperture 32 and enters the photomultiplier tube 33. However, when the height of the wafer 6 under test deviates from the focal plane of the scattered signal collector, Figure 5 This is a schematic diagram of the second type of scattered light collection provided in the embodiments of the present invention, as shown below. Figure 5 As shown, with the probe light position unchanged, the increased height of the wafer under test (6) leads to an increased defect height, which in turn causes the scattered light propagation path to deviate. This results in a change in the angle range of the scattered light received by the scattered light collector 31, and a decrease in the signal strength received by the photomultiplier tube 33, ultimately leading to low defect detection accuracy. Therefore, this embodiment of the invention provides a wafer defect detection method. Figure 6 This is a flowchart of the first wafer inspection method provided according to an embodiment of the present invention, combined with... Figures 1 to 6 As shown, it includes:

[0058] S10. Obtain the relationship between the height of the reflective surface and the height of the acquisition module. This relationship refers to the relationship between the height coordinates of the wafer under test 6 and the height coordinates of the reflected light illuminating the reflected light signal acquisition module 4.

[0059] The reflecting surface can be the plane reflecting the probe light. The height coordinates of the reflected light signal acquisition module 4 can be the height coordinates detected by the spot position detector 42 in the reflected light signal acquisition module 4. When the height of the reflecting surface changes, the height coordinates of the reflected light illuminating the reflected light signal acquisition module 4 will change. By obtaining the relationship between the height of the reflecting surface and the height of the acquisition module, the height of the reflecting surface can be determined by the height coordinates of the reflected light illuminating the reflected light signal acquisition module 4.

[0060] S11. Output the pre-scan signal to the motion module and receive the pre-scan coordinate information.

[0061] The pre-scan signal controls the activation of the motion module 2. It is understood that in this embodiment of the invention, the probe light does not move; only the wafer 6 under test moves, causing its surface to pass through the probe light spot to complete the scanning of the wafer surface. In some embodiments, Figure 7 This is a schematic diagram of a wafer motion trajectory provided according to an embodiment of the present invention, such as... Figure 7 As shown, the wafer under test 6 moves in a spiral trajectory via motion module 2. Additionally, during the pre-scanning process, only the reflected light signal acquisition module 4 can be activated, while the scattered light signal acquisition module 3 remains unactivated.

[0062] Among them, the pre-scan coordinate information can be the plane coordinate information of the probe light incident on the wafer 6 under test and the height coordinate information of the reflected light irradiating the reflected light signal acquisition module 4.

[0063] S12. Determine the fine scan coordinate information based on the pre-scan coordinate information and the relationship between the height of the reflective surface and the height of the acquisition module.

[0064] Among them, the fine scan coordinate information can be the plane coordinate information of the probe light incident on the wafer 6 under test and the height coordinate information of the wafer 6 under test.

[0065] Since the pre-scan coordinate information includes the plane coordinate information of the probe light incident on the wafer 6 under test and the height coordinate information of the reflected light signal acquisition module 4 corresponding to each plane coordinate information, the height of the wafer 6 under test is obtained by combining the height coordinate information of the reflected light signal acquisition module 4 with the relationship between the height of the reflecting surface and the height of the acquisition module, and then the fine scan coordinate information is determined.

[0066] S13. Adjust the motion path of the motion module according to the fine scan coordinate information and generate wafer defect information based on the acquired scattered light.

[0067] Since the fine scan coordinate information includes the height coordinate information of the wafer 6 under test, the motion path of the motion module 2 can be adjusted according to the fine scan coordinate information during the fine scan process. This ensures that the probe light irradiation point of the wafer 6 under test is always located at the focal plane of the scattered light collector 31, thereby ensuring the intensity of the scattered light signal and avoiding the problem of the defect size being calculated too small due to the decrease in the intensity of the scattered light signal. This improves the accuracy and reliability of wafer defect detection.

[0068] The technical solution of this invention obtains pre-scanning coordinate information by acquiring the relationship between the height of the reflective surface and the height of the acquisition module in advance and performing pre-scanning. The fine scan coordinate information is determined by combining the pre-scanning coordinate information and the relationship between the height of the reflective surface and the height of the acquisition module. The motion path of the motion module is adjusted in real time during the fine scan based on the fine scan coordinate information. This avoids the problem of inaccurate detection size and positioning of wafer defects when the wafer under test is in a non-flat state, and improves the accuracy of wafer defect detection.

[0069] Based on the above embodiments, Figure 8 This is a flowchart of a second wafer inspection method provided according to an embodiment of the present invention, combined with... Figures 1 to 5 and Figure 8 As shown, motion module 2 includes a vertical motion motor 220 and a height calibration column 23. The vertical motion motor 220 can drive the wafer 6 under test to move in the y-direction. The height calibration column 23 follows the motion module 22 and can be used for vertical motion calibration.

[0070] The wafer defect detection method includes:

[0071] S20. Obtain the coordinates of the reference origin. The reference origin coordinates are the height coordinates of the reflected light illuminating the reflected light signal acquisition module 4 when the reflective surface of the height calibration column 23 is located at the focal plane of the scattered light signal acquisition module 3.

[0072] Specifically, the reflective surface of the height calibration column 23 can be adjusted to be located at the focal plane of the scattered light signal acquisition module 3, and this height can be recorded as point 0. The height coordinates of the reflected light illuminating the reflected light signal acquisition module 4 at this time can then be obtained. That is, the coordinates of the reference origin are obtained. .

[0073] For example, the motion module 22 moves the height calibration column 23 to the vicinity of the probe light so that the probe light illuminates the upper surface of the height calibration column 23; the vertical motion motor 220 is then adjusted so that the height of the upper surface of the height calibration column 23 is located at the focal plane of the scattered light collector 31. After the adjustment is completed, this position is recorded as the reference origin coordinates.

[0074] S21. Control the vertical motion motor to move, thereby moving the height calibration column and acquiring the moving distance dy and calibration height coordinate z of the height calibration column. The calibration height coordinate z is the height coordinate of the reflected light illuminating the reflected light signal acquisition module 4 corresponding to the moving distance dy.

[0075] Specifically, the vertical motion motor 220 is controlled to move, causing the height calibration column 23 to move upward or downward a distance dy relative to the reference origin. The calibration height coordinate z is recorded at this point, and the coordinates of this position relative to the reference origin are: The vertical motion motor 220 can be continuously moved based on this, and the coordinates of each position can be recorded, thus obtaining (0, z0), (y1, z1), (y2, z2)... (y... n , z n ), where z1 is the height coordinate of the reflected light illuminating the reflected light signal acquisition module 4 corresponding to the first moving distance dy; z2 is the height coordinate of the reflected light illuminating the reflected light signal acquisition module 4 corresponding to the second moving distance dy; z n y1 represents the height coordinate of the reflected light illuminating the reflected light signal acquisition module 4 corresponding to the nth moving distance dy; y2 represents the height of the reflective surface of the first moving height calibration column 23 relative to the origin; y3 represents the height of the reflective surface of the second moving height calibration column 23 relative to the origin; y4 represents the height of the reflective surface of the second moving height calibration column 23 relative to the origin; y5 represents the height of the reflective surface of the second moving height calibration n The height of the reflective surface of column 23 relative to the origin is used to calibrate the height of the nth movement.

[0076] S22. Based on the coordinates of the reference origin. The relationship between the height of the reflector and the height of the acquisition module is determined by the moving distance dy and the calibration height coordinate z.

[0077] Among them, based on the coordinates of the reference origin By fitting the moving distance dy and the calibration height coordinates, a functional relationship can be derived, which can then determine the relationship between the height of the reflective surface and the height of the acquisition module.

[0078] In some embodiments, the relationship between the height of the reflective surface and the height of the acquisition module is as follows: Where y is the height of the reflecting surface; a is a constant.

[0079] S23, Output the pre-scan signal to the motion module and receive the pre-scan coordinate information.

[0080] S24. Determine the fine scan coordinate information based on the pre-scan coordinate information and the relationship between the height of the reflective surface and the height of the acquisition module.

[0081] S25. Adjust the motion path of the motion module according to the fine scan coordinate information and generate wafer defect information based on the acquired scattered light.

[0082] The technical solution of this invention obtains the reference origin coordinates, the moving distance dy, and the calibration height coordinates z by controlling the vertical motion motor and the height calibration column. Then, a fitting function is used to obtain the relationship between the height of the reflective surface and the height of the acquisition module, thereby realizing the precise adjustment of the motion path during the fine scanning process.

[0083] Based on the above embodiments, Figure 9 This is a flowchart of the third wafer inspection method provided according to an embodiment of the present invention, combined with... Figures 1 to 5 and Figure 9 As shown, the wafer defect detection method includes:

[0084] S30. Obtain the relationship between the height of the reflective surface and the height of the acquisition module. This relationship refers to the relationship between the height coordinates of the wafer under test 6 and the height coordinates of the reflected light illuminating the reflected light signal acquisition module 4.

[0085] S31, output the pre-scan signal to the motion module and receive the pre-scan coordinate information.

[0086] S32. Based on the pre-scan coordinate information The relationship between the height of the reflective surface and the height of the acquisition module determines the fine scan coordinate information. Where r is the distance from the center of the wafer 6 to the point where the probe light is incident on it; The angle between the line connecting the position of the probe light incident on the wafer 6 under test to the center of the wafer 6 under test and the polar axis.

[0087] The position of the probe light incident on the wafer 6 under test can be represented in polar coordinates. During the pre-scan, the position of the probe light incident on the wafer 6 under test and the height coordinates of the reflected light illuminating the reflected light signal acquisition module 4 are obtained through the horizontal movement of the motion module 2. The relationship between the height of the reflecting surface and the height of the acquisition module is then established. Calculate the fine scan coordinate information .

[0088] S33. Adjust the motion path of the motion module according to the fine scan coordinate information and generate wafer defect information based on the acquired scattered light.

[0089] The technical solution of this invention uses pre-scan coordinate information, the relationship between the height of the reflective surface and the height of the acquisition module, and fine scan coordinate information to accurately calculate the height of the reflective surface of the wafer under test corresponding to each probe light position, thereby accurately adjusting the movement path of the wafer under test in defect detection.

[0090] Based on the above embodiments, Figure 10 This is a flowchart of the fourth wafer inspection method provided according to an embodiment of the present invention. Figures 1 to 5 and Figure 10 As shown, the wafer defect detection method includes:

[0091] S40. Obtain the relationship between the height of the reflective surface and the height of the acquisition module. This relationship refers to the relationship between the height coordinates of the wafer under test 6 and the height coordinates of the reflected light illuminating the reflected light signal acquisition module 4.

[0092] S41, output the pre-scan signal to the motion module and receive the pre-scan coordinate information.

[0093] S42. Determine the fine scan coordinate information based on the pre-scan coordinate information and the relationship between the height of the reflective surface and the height of the acquisition module.

[0094] S43. Based on the fine scan coordinate information Determine each detection point The corresponding adjustment height is -y.

[0095] The detection point can be the polar coordinates on the wafer 6 under test where the probe light is incident. When the wafer 6 under test moves along an Archimedean spiral trajectory, the detection point can be a point on that trajectory. When the fine scan coordinate information is calculated... Then, during the fine scanning process, when the probe light is incident on the detection point... If the height of the reflective surface of the wafer 6 under test is y, then in order to ensure that the reflective surface is at the focal plane of the scattering signal collector, the height is adjusted to -y, that is, reverse adjustment is performed.

[0096] S44. According to each detection point The corresponding height-y adjustment adjusts the motion path of the motion module and generates wafer defect information based on the acquired scattered light.

[0097] Among them, according to each detection point The corresponding height-y adjustment of the motion path of the motion module 2 ensures that the reflective surface of the probe light incident during the fine scanning process is maintained at the reference origin coordinates, thereby obtaining more accurate wafer defect information.

[0098] Based on the above embodiments, Figure 11 This is a flowchart of the fifth wafer inspection method provided according to an embodiment of the present invention. Figures 1 to 5 and Figure 11 As shown, the wafer defect detection method includes:

[0099] S50. Obtain the relationship between the height of the reflective surface and the height of the acquisition module. This relationship refers to the relationship between the height coordinates of the wafer under test 6 and the height coordinates of the reflected light illuminating the reflected light signal acquisition module 4.

[0100] S51, output the pre-scan signal to the motion module and receive the height information from the reflected light signal acquisition module.

[0101] The height information can be the height coordinates of the reflected light illuminating the reflected light signal acquisition module 4.

[0102] S52. Determine the pre-scan coordinate information based on the motion path and height information of the motion module.

[0103] In this embodiment of the invention, since the position of the probe light does not change and only the movement of the wafer 6 under test is controlled, the planar coordinate information of the probe light incident on the wafer 6 under test can be determined according to the movement path of the motion module 2. Pre-scanning coordinate information is then determined based on the planar coordinate information and height information.

[0104] S53. Determine the fine scan coordinate information based on the pre-scan coordinate information and the relationship between the height of the reflective surface and the height of the acquisition module.

[0105] S54. Adjust the motion path of the motion module according to the fine scan coordinate information and generate wafer defect information based on the acquired scattered light.

[0106] Based on the above embodiments, Figure 12 This is a flowchart of the sixth wafer inspection method provided according to an embodiment of the present invention. Figures 1 to 5 and Figure 12 As shown, the wafer defect detection method includes:

[0107] S60. Obtain the relationship between the height of the reflective surface and the height of the acquisition module.

[0108] S61, output the pre-scan signal to the motion module and receive the pre-scan coordinate information.

[0109] S62. Determine the fine scan coordinate information based on the pre-scan coordinate information and the relationship between the height of the reflective surface and the height of the acquisition module.

[0110] S63. Adjust the motion path of the motion module according to the fine scan coordinate information and generate wafer defect information based on the acquired scattered light.

[0111] S64. Determine the location and size of wafer defects based on wafer defect information.

[0112] In this invention, because the scattered light deviates from its focal point after being collected and focused by the scattered light collector 31, and some light is blocked by the aperture 32, the intensity of the scattered light signal detected by the photomultiplier tube 33 decreases, resulting in a smaller calculated defect size. Changes in the height of the wafer surface also cause the detected defect coordinates to deviate from the actual coordinates. Therefore, the wafer defect information collected by the fine scanning in this embodiment avoids the problem of inaccurate detection size and positioning of wafer defects when the wafer 6 under test is in a non-flat state, thus improving the accuracy of wafer defect detection.

[0113] Since the wafer defect detection device provided in this embodiment of the invention includes the wafer defect detection method provided in the above embodiment, and has the same or corresponding technical effects as the wafer defect detection method, it will not be described in detail here.

[0114] Based on the same inventive concept, embodiments of the present invention also provide a computer device. Figure 13 This is a schematic diagram of an electronic device structure applied to a wafer defect detection method according to an embodiment of the present invention, as shown below. Figure 13 As shown, it includes a memory, a processor, and a computer program stored in the memory and capable of running on the processor. When the processor executes the program, it implements a wafer defect detection method.

[0115] The term "electronic device" is intended to refer to various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. Electronic devices can also refer to various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices (e.g., helmets, glasses, watches), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0116] like Figure 13 As shown, the electronic device 50 includes at least one processor 51 and a memory, such as a read-only memory (ROM) 52 and a random access memory (RAM) 53, communicatively connected to the at least one processor 51. The memory stores computer programs executable by the at least one processor. The processor 51 can perform various appropriate actions and processes based on the computer program stored in the ROM 52 or loaded from storage unit 58 into the RAM 53. The RAM 53 can also store various programs and data required for the operation of the electronic device 50. The processor 51, ROM 52, and RAM 53 are interconnected via a bus 54. An input / output (I / O) interface 55 is also connected to the bus 54.

[0117] Multiple components in electronic device 50 are connected to I / O interface 55, including: input unit 56, such as keyboard, mouse, etc.; output unit 57, such as various types of monitors, speakers, etc.; storage unit 58, such as disk, optical disk, etc.; and communication unit 59, such as network card, modem, wireless transceiver, etc. Communication unit 59 allows electronic device 50 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0118] Processor 51 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 51 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, digital signal processors (DSPs), and any suitable processor, controller, microcontroller, etc. Processor 51 performs the various methods and processes described above, such as those applied to wafer defect detection methods.

[0119] Based on the same inventive concept, embodiments of the present invention also provide a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a wafer defect detection method.

[0120] Of course, the computer-readable storage medium provided in the embodiments of the present invention has computer-executable instructions that are not limited to the method operations described above, and can also perform related operations in the wafer defect detection method provided in any embodiment of the present invention. (Continue to refer to...) Figure 13 As shown, it is tangibly contained in a computer-readable storage medium, such as storage unit 58. In some embodiments, part or all of the computer program may be loaded and / or mounted on electronic device 50 via ROM 52 and / or communication unit 59. When the computer program is loaded into RAM 53 and executed by processor 51, one or more steps of the wafer defect detection method described above may be performed. Alternatively, in other embodiments, processor 51 may be configured to perform the wafer defect detection method by any other suitable means (e.g., by means of firmware).

[0121] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0122] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0123] In the context of embodiments of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0124] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0125] 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 method for detecting wafer defects, characterized in that, It is used in a wafer inspection device; the wafer inspection device includes: an optical module, a motion module, a scattered light signal acquisition module, a reflected light signal acquisition module, and a control module; The optical module emits probe light to the wafer under test; the motion module carries the wafer under test and moves it; the scattered light signal acquisition module receives the scattered light from the wafer under test; the reflected light signal acquisition module receives the reflected light from the wafer under test; the motion module includes a vertical motion motor and a height calibration column. The control module is communicatively connected to the motion module, the scattered light signal acquisition module, and the reflected light signal acquisition module, respectively. The wafer defect detection method includes: The relationship between the height of the reflective surface and the height of the acquisition module is obtained; wherein, the relationship between the height of the reflective surface and the height of the acquisition module is the relationship between the height coordinates of the wafer under test and the height coordinates of the reflected light illuminating the reflected light signal acquisition module; Output a pre-scan signal to the motion module and receive pre-scan coordinate information; The fine scan coordinate information is determined based on the pre-scan coordinate information and the relationship between the height of the reflective surface and the height of the acquisition module; The motion path of the motion module is adjusted according to the fine scan coordinate information, and wafer defect information is generated according to the acquired scattered light. The relationship between the height of the reflective surface and the height of the acquisition module is obtained, including: Obtain the coordinates of the reference origin Wherein, the reference origin coordinates are the height coordinates of the reflected light illuminating the reflected light signal acquisition module when the reflecting surface of the height calibration column is located at the focal plane of the scattered light signal acquisition module; The vertical motion motor is controlled to move to drive the height calibration column to move and the moving distance dy and calibration height coordinate z of the height calibration column are obtained; wherein, the calibration height coordinate z is the height coordinate of the reflected light illuminating the reflected light signal acquisition module corresponding to the moving distance dy; Based on the coordinates of the reference origin The moving distance dy and the calibration height coordinate z determine the relationship between the height of the reflective surface and the height of the acquisition module; The relationship between the height of the reflective surface and the height of the acquisition module is as follows: ; Where y is the height of the reflective surface; a is a constant.

2. The wafer defect detection method according to claim 1, characterized in that, The fine scan coordinate information is determined based on the pre-scan coordinate information and the relationship between the height of the reflective surface and the height of the acquisition module, including: According to the pre-scan coordinate information The relationship between the height of the reflective surface and the height of the acquisition module determines the fine scanning coordinate information. ; Where r is the distance from the center of the wafer to which the probe light is incident; The angle between the line connecting the position where the probe light is incident on the wafer under test to the center of the wafer under test and the polar axis.

3. The wafer defect detection method according to claim 2, characterized in that, Adjusting the motion path of the motion module based on the fine scan coordinate information includes: Based on the fine scan coordinate information Determine each detection point The corresponding adjustment height is -y; According to each of the detection points The corresponding adjustment height -y adjusts the motion path of the motion module.

4. The wafer defect detection method according to claim 1, characterized in that, Receive pre-scan coordinate information, including: Receive the height information from the reflected light signal acquisition module; The pre-scan coordinate information is determined based on the motion path of the motion module and the height information.

5. The wafer defect detection method according to claim 1, characterized in that, After generating wafer defect information based on the obtained scattered light, the method further includes: The location and size of the wafer defects are determined based on the wafer defect information.

6. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the wafer defect detection method as described in any one of claims 1-5.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the wafer defect detection method as described in any one of claims 1-5.

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