Wafer processing system, method, electronic device, and computer medium

Abstract

The application provides a wafer processing system, method, electronic device and computer medium. The wafer processing system comprises a wafer polishing assembly including a polishing disc; an eddy current sensor arranged on the polishing disc, during wafer polishing, the eddy current sensor rotates with the polishing disc to form a circular track, a first line connecting the horizontal projection of the center of the polishing disc and the horizontal projection of the center of the wafer intersects with the horizontal projection of the circular track, and the horizontal projection of a preset marker intersects with the horizontal projection of the circular track, the position of the marker remains unchanged, and the eddy current sensor is used to collect an eddy current signal during wafer polishing; a controller is used to determine the signal included angle of the marker based on the marker signal, determine the angle deviation value of the signal included angle and the actual included angle of the marker, calibrate the wafer topography characteristic signal according to the angle deviation value, and control the wafer polishing assembly to polish the wafer. The application can improve the accuracy of determining the thickness of the wafer film.

Description

Technical Field

[0001] This application belongs to the field of semiconductor manufacturing technology, and more specifically, relates to a wafer processing system, method, electronic device and computer medium. Background Technology

[0002] In the integrated circuit manufacturing process, a conductive layer is deposited on a silicon wafer, and CMP (chemical mechanical polishing) is used to planarize the wafer surface. During CMP, eddy current signals and corresponding position signals from eddy current sensors need to be acquired in real time. Based on the eddy current signals acquired by the eddy current sensors and their position signals, the film thickness on the wafer is determined. The measured film thickness is then used to detect the polishing endpoint or to adjust the polishing parameters.

[0003] In related technologies, the eddy current signal and the position signal of the eddy current sensor are prone to being out of sync, resulting in low accuracy in determining the thickness of the wafer thin film. Summary of the Invention

[0004] The purpose of this application is to provide a wafer processing system, method, electronic device, and computer medium to solve or at least alleviate one or more of the above-mentioned and other problems existing in the prior art.

[0005] A first aspect of this application provides a wafer fabrication system, comprising:

[0006] Wafer polishing assembly, including a polishing disk for use as a wafer polishing base;

[0007] An eddy current sensor is mounted on a polishing pad. During wafer polishing, the eddy current sensor forms a circular trajectory as the polishing pad rotates. The first line connecting the horizontal projection of the polishing pad center and the horizontal projection of the wafer center intersects with the horizontal projection of the circular trajectory. The horizontal projection of a preset marker also intersects with the horizontal projection of the circular trajectory. The position of the marker remains unchanged. The eddy current sensor is used to collect eddy current signals during wafer polishing. The eddy current signals include: marker signals and wafer morphology feature signals.

[0008] The controller is used to determine the signal angle of the marker based on the marker signal, wherein the signal angle is the angle between the first line and the second line, and the second line is the line connecting the intersection of the horizontal projection of the polishing disk center and the horizontal projection of the marker determined based on the marker signal and the horizontal projection of the circular trajectory; determine the angular deviation value between the signal angle and the actual angle of the marker; calibrate the wafer morphology feature signal according to the angular deviation value; and control the wafer polishing assembly to polish the wafer.

[0009] In one embodiment, when the controller is used to determine the signal angle of a marker based on the marker signal, it specifically performs the following:

[0010] The distance between the intersection point and the horizontal projection of the wafer center is determined based on the peak value of the signal amplitude in the marker signal;

[0011] Obtain the distance between the horizontal projection of the polishing pad center and the horizontal projection of the wafer center;

[0012] Obtain the distance between the horizontal projection of the polishing disk center and the intersection point;

[0013] The signal angle of the marker is calculated based on the distance between the intersection point and the horizontal projection of the wafer center, the distance between the horizontal projection of the polishing pad center and the horizontal projection of the wafer center, and the distance between the horizontal projection of the polishing pad center and the intersection point.

[0014] In one embodiment, when the controller is used to determine the signal angle of a marker based on the marker signal, it specifically performs the following:

[0015] Determine the average value of the signal amplitude in the marker signal;

[0016] Determine the angle corresponding to the average value during the rising phase of the signal amplitude and the angle corresponding to the average value during the falling phase of the signal amplitude in the signal of the marker.

[0017] The average of the angles corresponding to the average value during the rising phase of the signal amplitude and the average value during the falling phase of the signal amplitude is taken as the signal angle of the marker.

[0018] In one embodiment, when the controller is used to calibrate the wafer morphology feature signal based on the angle deviation value, it is specifically used to:

[0019] The deviation distance of the wafer morphology feature signal is determined based on the angle deviation value;

[0020] The wafer morphology feature signal is calibrated based on the deviation distance.

[0021] A second aspect of this application provides a wafer fabrication method, including:

[0022] Control the wafer polishing assembly to polish the wafer;

[0023] The eddy current signal collected by the eddy current sensor during the wafer polishing process is obtained. The eddy current signal includes: marker signal and wafer morphology feature signal.

[0024] The signal angle of the marker is determined based on the marker signal. The signal angle is the angle between the first line connecting the horizontal projection of the polishing pad center and the horizontal projection of the wafer center, and the second line connecting the second line. The second line is the line connecting the intersection of the horizontal projection of the polishing pad center and the horizontal projection of the marker determined based on the marker signal and the horizontal projection of the circular trajectory.

[0025] Determine the angular deviation between the signal angle and the actual angle between the marker;

[0026] The wafer morphology feature signal is calibrated based on the angle deviation value;

[0027] Among them, the eddy current sensor is set on the polishing disk. During the wafer polishing process, the eddy current sensor forms a circular trajectory as the polishing disk rotates. The first line intersects with the horizontal projection of the circular trajectory, and the horizontal projection of the marker intersects with the horizontal projection of the circular trajectory. The position of the marker remains unchanged.

[0028] In one embodiment, determining the signal angle of the marker based on the marker signal includes:

[0029] The distance between the intersection point and the horizontal projection of the wafer center is determined based on the peak value of the signal amplitude in the marker signal;

[0030] Obtain the distance between the horizontal projection of the polishing pad center and the horizontal projection of the wafer center;

[0031] Obtain the distance between the horizontal projection of the polishing disk center and the intersection point;

[0032] The signal angle of the marker is calculated based on the distance between the intersection point and the horizontal projection of the wafer center, the distance between the horizontal projection of the polishing pad center and the horizontal projection of the wafer center, and the distance between the horizontal projection of the polishing pad center and the intersection point.

[0033] In one embodiment, the method further includes:

[0034] When the eddy current sensor detects no marker signal within a preset time period, or detects an angular deviation value greater than a preset deviation range, the position of the marker is calibrated.

[0035] A third aspect of this application provides an eddy current monitoring method, comprising:

[0036] Controlling the relative motion between the wafer and the polishing pad;

[0037] During the relative motion between the wafer and the polishing pad, an eddy current sensor mounted on the polishing pad monitors eddy current signals, which include marker signals and wafer morphology feature signals. The signal angle of the marker is determined based on the marker signal, and the angular deviation value between the signal angle and the actual angle of the marker is determined. The wafer morphology feature signals are then calibrated based on the angular deviation value.

[0038] During the wafer polishing process, the eddy current sensor forms a circular trajectory as the polishing disk rotates. The first line connecting the horizontal projection of the polishing disk center and the horizontal projection of the wafer center intersects with the horizontal projection of the circular trajectory. The horizontal projection of the preset marker intersects with the horizontal projection of the circular trajectory, and the position of the marker remains unchanged.

[0039] A fourth aspect of this application provides a chemical mechanical polishing apparatus, comprising: a polishing head, a polishing disc, and a liquid supply module, wherein an eddy current sensor is disposed on the polishing disc, and a marker is disposed on the liquid supply arm of the liquid supply module. The marker is used to enable the eddy current sensor to acquire the marker signal, and the marker signal is used to calibrate the wafer morphology feature signal acquired by the eddy current sensor.

[0040] In one embodiment, the surface of the marker is smooth; the marker is connected to the liquid supply arm and the connection is smoothly transitioned.

[0041] A fifth aspect of this application provides an electronic device including a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor executes the computer program to implement the steps of the methods described above.

[0042] A sixth aspect of the embodiments of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the methods described above.

[0043] A seventh aspect of this application provides a computer program product, including a computer program or computer executable instructions, wherein when the computer program or computer executable instructions are executed by a processor, the steps of the methods described above are implemented.

[0044] The beneficial effects of the embodiments of this application are as follows: In the solution of this application, by adding markers, the marker signals contained in the eddy current signals are used to calibrate the wafer morphology feature signals, thereby realizing the alignment of the position signal of the eddy current sensor with the eddy current signal, improving the synchronization between the position signal of the eddy current sensor and the acquired eddy current signal, and thus making the wafer thin film thickness determined based on the synchronization between the position signal and the eddy current signal more accurate, and also making the determination of the polishing endpoint and the dynamic adjustment of process parameters more accurate. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of this application, 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.

[0046] Figure 1 This is a schematic diagram illustrating the delay between the eddy current signal and the position signal before calibration of the wafer morphology feature signal, provided in an embodiment of this application.

[0047] Figure 2 This is a schematic diagram of an eddy current signal provided in an embodiment of this application;

[0048] Figure 3 This is a schematic diagram illustrating the impact of the offset between the eddy current signal and the position signal on the compensation accuracy of the wafer edge region, as provided in an embodiment of this application.

[0049] Figure 4 This is a schematic diagram illustrating the delay between the eddy current signal and the position signal after calibration of the wafer morphology feature signal, as provided in an embodiment of this application.

[0050] Figure 5 This is a schematic diagram of the structure of a wafer polishing system provided in one embodiment of this application;

[0051] Figure 6 A top view of a wafer polishing system in one of the positions during the wafer polishing process provided in an embodiment of this application;

[0052] Figure 7 This is a top view of a wafer polishing system provided in an embodiment of this application;

[0053] Figure 8 A top view of a wafer polishing system when the position of a marker provided in an embodiment of this application is shifted;

[0054] Figure 9 A schematic diagram of an eddy current signal provided in an embodiment of this application;

[0055] Figure 10 A schematic diagram of the signal angle of a marker provided in one embodiment of this application;

[0056] Figure 11 A schematic diagram of a marker signal provided in an embodiment of this application;

[0057] Figure 12 This is a schematic diagram of the eddy current signal before calibration of the wafer morphology feature signal, provided in an embodiment of this application.

[0058] Figure 13 This is a schematic diagram of the eddy current signal after calibration of the wafer morphology feature signal, provided in an embodiment of this application.

[0059] Figure 14 This is a schematic diagram illustrating the change in the offset between the eddy current signal and the position signal before and after calibration of the wafer morphology feature signal, according to an embodiment of this application.

[0060] Figure 15 A schematic flowchart of a wafer fabrication method provided in an embodiment of this application;

[0061] Figure 16 A schematic flowchart of an eddy current monitoring method provided in an embodiment of this application;

[0062] Figure 17 This is a schematic block diagram of an electronic device provided in an embodiment of this application. Detailed Implementation

[0063] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0064] During data transmission, the transmission of eddy current signals and position signals can be affected by factors such as transmission delay and polishing head oscillation, leading to data jitter. Even with software synchronization methods, discrepancies in transmission time can introduce deviations (e.g., ...). Figure 1 (D1 / D2 time in the data).

[0065] Using hardware position calibration (such as Hall sensors) also introduces unpredictable delays during hardware triggering and signal transmission (e.g., Figure 1 The transmission delay between the eddy current signal and the position signal can cause them to be out of sync, especially in the wafer edge region. Due to the oscillation of the polishing head and the dynamics of the process, the delay effect is significantly amplified, ultimately manifesting as shown in the wafer surface topography map. Figure 2 The 2-3mm horizontal jitter shown is an example. This jitter directly interferes with the real-time measurement accuracy of wafer thin film thickness, thus affecting the determination of the polishing endpoint and the dynamic adjustment of process parameters. It also affects the edge compensation accuracy, as shown in the example. Figure 3 As shown, the offset between the eddy current signal and the position signal has a significant impact on the compensation accuracy of the wafer edge region.

[0066] Therefore, a solution is needed to address the issue of asynchrony between the eddy current signal and the position signal of the eddy current sensor, so as to improve the accuracy of wafer thin film thickness determination based on the synchronization of the position signal and the eddy current signal, and to make the determination of polishing endpoint and dynamic adjustment of process parameters more accurate.

[0067] This application primarily improves the accuracy of endpoint detection by adding markers to establish the correspondence between position signals and eddy current signals. This corrects the offset caused by communication transmission delays, thereby enhancing edge compensation accuracy and voltage regulation stability. The proposed solution reduces the jitter between position and eddy current signals to below 1 mm. After calibrating the wafer morphology feature signals using this solution, the delay between the eddy current and position signals can be as follows: Figure 4 As shown, the solution of this application effectively improves the problem of asynchrony between eddy current signals and position signals.

[0068] To make the objectives, technical solutions, and advantages of this application clearer, the following description will be provided in conjunction with the accompanying drawings and specific embodiments.

[0069] Figure 5 This is a schematic diagram of a wafer polishing system according to an embodiment of this application. The wafer processing system includes a wafer polishing assembly 110, an eddy current sensor 116, and a controller (not shown). The wafer polishing assembly 110 includes a polishing disk 111 serving as a wafer polishing base. The wafer polishing assembly 110 also includes a polishing pad 112, a polishing head 113, and a liquid supply module 114. Figure 5 The arrows in the diagram are used to indicate the corresponding rotation direction during wafer polishing;

[0070] Among them, the polishing disk 111 is used to provide mechanical motion power and stability support for the wafer polishing process, drive the polishing pad 112 to rotate at high speed, and achieve wafer polishing through friction.

[0071] Polishing pad 112 is used as the working surface for mechanical polishing, directly contacting the wafer to ensure consistent force on the wafer surface.

[0072] Polishing head 113 is used to hold the wafer and precisely control the polishing pressure and movement.

[0073] The liquid supply module 114 is used to continuously deliver polishing liquid and maintain the chemical reaction environment during the wafer polishing process.

[0074] Eddy current sensor 116 is mounted on polishing disc 111. Further, see... Figure 6As shown, during wafer polishing, the eddy current sensor 116 rotates with the polishing disk 111, forming a circular trajectory. The first line connecting the horizontal projection O of the polishing disk center and the horizontal projection P of the wafer center intersects with the horizontal projection of the circular trajectory. Furthermore, the horizontal projection of the preset marker 115 intersects with the horizontal projection of the circular trajectory, and the intersection point is... Figure 6 In section B, the position of marker 115 remains unchanged. Eddy current sensor 116 is used to acquire eddy current signals during wafer polishing, including marker signals and wafer topography feature signals.

[0075] Specifically, the intersection point of the horizontal projection of marker 115 and the horizontal projection of the circular trajectory refers to the center point of the intersection line between the horizontal projection of marker 115 and the circular trajectory.

[0076] Further, see Figure 7 As shown, during the wafer polishing process, wafer 117 rotates while moving along the first connection line. Figure 6 This is a top view of the wafer polishing system when wafer 117 is in one of the positions during the wafer polishing process.

[0077] In one embodiment, the first line connecting the horizontal projection of the polishing pad center and the horizontal projection of the wafer center can refer to a ray extending from the horizontal projection of the polishing pad center to the horizontal projection of the wafer center.

[0078] In one embodiment, the point where the first line connecting the horizontal projection of the polishing pad center and the horizontal projection of the wafer center intersects with the horizontal projection of the circular trajectory coincides with the horizontal projection of the wafer center.

[0079] Before wafer polishing, the position of marker 115 needs to be calibrated to ensure that the actual included angle of marker 115 is known and stable. During wafer polishing, if the position of marker 115 shifts due to shaking of the wafer polishing system or other reasons, the actual included angle of marker 115 will change. For example... Figure 8 As shown, the offset of the position of marker 115 leads to an offset of the actual included angle of marker 115, such as the offset angle e. This results in poor accuracy and low reliability in the calibration of the wafer morphology feature signal.

[0080] Therefore, when the eddy current sensor fails to detect the marker signal within a preset time period, or detects an angular deviation value exceeding a preset deviation range, the position of marker 115 needs to be calibrated. Calibration of marker 115 can be performed by first moving it to the initial calibration position, or by calibrating at the current position or a new position, updating the actual included angle of marker 115 accordingly. This ensures that the calibration of wafer morphology feature signals maintains high accuracy during wafer polishing, improving the reliability of the wafer processing system. A tooling fixture can be used for calibration of marker 115.

[0081] In one embodiment, it can also be determined whether the position of the marker 115 has shifted by observing the eddy current signal; however, this application does not limit this.

[0082] The position of marker 115 is set such that the eddy current sensor can pass over marker 115 during its rotation, that is, the marker signal can be collected.

[0083] The actual included angle of marker 115 is the angle between the first connecting line and the line connecting the center of the polishing disk and the intersection of the actual horizontal projection of marker 115 and the horizontal projection of the circular trajectory.

[0084] In one embodiment, the marker 115 is made of metal and can be disposed on the liquid supply arm of the liquid supply module 114 or fixed by a bracket.

[0085] In one embodiment, the marker 115 has a shape that is wider at the top and narrower at the bottom. This structure ensures that when the eddy current sensor 116 passes over the marker 115, only a relatively obvious peak signal can be detected.

[0086] In one embodiment, the surface of the marker 115 is smooth; the marker 115 is connected to the liquid supply arm and the connection is smoothly transitioned. In one embodiment, the marker 115 may be embedded in the liquid supply arm.

[0087] In one embodiment, the marker 115 may be encased in plastic to prevent its metallic properties from contaminating the chemical environment of wafer polishing. Furthermore, it also prevents the marker 115 itself from being corroded in the chemical environment of wafer polishing, thus affecting the magnitude of the marker signal. The marker is made of a material with high insulation strength and low dielectric constant, such as Teflon or Pyrene C.

[0088] In one embodiment, during the wafer polishing process, as the polishing disk 111 rotates, the eddy current signal of the eddy current sensor 116 can be the signal collected by the eddy current sensor 116 as it rotates one revolution with the polishing disk.

[0089] In one embodiment, the eddy current signal can be seen as... Figure 9 As shown. The horizontal axis represents the distance between the corresponding signal point in the eddy current signal and the horizontal projection of the wafer center, and the vertical axis represents the amplitude of the eddy current signal. The distance between the signal point and the horizontal projection of the wafer center refers to the distance between the horizontal projection of the eddy current sensor and the horizontal projection of the wafer center when the eddy current sensor collects the amplitude of the signal point.

[0090] In this application, distance and connection refer to distance and connection on the corresponding horizontal projection.

[0091] When the eddy current sensor 116 rotates into the wafer edge, the eddy current signal shows a rising edge; when it rotates away from the wafer edge, the eddy current signal shows a falling edge. In addition to the marker signal and wafer morphology feature signal, the eddy current signal also includes a baseline signal. The baseline signal refers to the signal collected when the rotation trajectory of the eddy current sensor 116 does not cross the wafer 117 or the marker 115.

[0092] The following steps S101-S104 can be executed by the controller.

[0093] S101. Determine the signal angle of the marker based on the marker signal. The signal angle is the angle between the first connecting line and the second connecting line. The second connecting line is the line connecting the intersection of the horizontal projection of the polishing disk center and the horizontal projection of the marker determined based on the marker signal and the horizontal projection of the circular trajectory.

[0094] like Figure 10 As shown, the signal angle Let P be the angle between the first line and the horizontal projection O of the polishing pad center, and the second line connecting the intersection point B of the horizontal projection of the marker 115 determined based on the marker signal and the horizontal projection of the circular trajectory, and let P be the horizontal projection of the wafer center.

[0095] S102. Determine the angular deviation between the signal angle and the actual angle between the marker;

[0096] S103. Calibrate the wafer morphology feature signal based on the angle deviation value;

[0097] S104. Control the wafer polishing assembly 110 to polish the wafer.

[0098] In some embodiments, when the controller is used to perform the aforementioned S101, that is, to perform the determination of the signal angle of the marker based on the marker signal, it is specifically used to perform the following steps S1011-S1014:

[0099] S1011. Determine the distance between the intersection point and the horizontal projection of the wafer center based on the peak value of the signal amplitude in the marker signal. The distance between the intersection point and the horizontal projection of the wafer center refers to the distance between the eddy current sensor and the horizontal projection of the wafer center when the eddy current sensor passes through the intersection point. The location of the peak value of the signal amplitude in the marker signal can be found in [reference needed]. Figure 11 As shown.

[0100] Specifically, the amplitude of each signal point included in the eddy current signal corresponds to the distance of the horizontal projection of that signal point to the center of the wafer.

[0101] Accordingly, the peak value of the marker signal can be determined based on the amplitude of each signal point included in the eddy current signal; the distance between the signal point corresponding to the peak value and the horizontal projection of the wafer center is taken as the distance between the intersection point and the horizontal projection of the wafer center. Figure 9 L in the figure represents the distance between the intersection point and the horizontal projection of the wafer center.

[0102] S1012. Obtain the distance between the horizontal projection of the polishing pad center and the horizontal projection of the wafer center;

[0103] Specifically, the distance between the horizontal projection of the polishing pad center and the horizontal projection of the wafer center is a known value and can be pre-stored in memory. Figure 10 The length of op in the figure is the distance between the horizontal projection O of the polishing pad center and the horizontal projection P of the wafer center.

[0104] S1013. Obtain the distance between the horizontal projection of the polishing disk center and the intersection point;

[0105] Figure 10 The length of ob in the equation is the distance between the horizontal projection of the center O of the polishing disk and the intersection point B.

[0106] S1014. Calculate the signal angle of the marker based on the distance between the intersection point and the horizontal projection of the wafer center, the distance between the horizontal projection of the polishing pad center and the horizontal projection of the wafer center, and the distance between the horizontal projection of the polishing pad center and the intersection point.

[0107] Specifically, each included angle can be calculated and determined using geometric algorithms, which will not be elaborated here.

[0108] In other embodiments, when the controller is used to perform the aforementioned S101, that is, to perform the determination of the signal angle of the marker based on the marker signal, it is specifically used to perform the following steps S011-S013:

[0109] S011. Determine the average value of the signal amplitude in the marker signal;

[0110] The average value of the signal amplitude in the marker signal is the ratio of the sum of the amplitudes of all signal points to the number of signal points in the marker signal.

[0111] S012. Determine the angle corresponding to the average value during the rising phase of the signal amplitude and the angle corresponding to the average value during the falling phase of the signal amplitude in the signal of the marker.

[0112] The positions of the corresponding signal points for the average value during the rising phase and the average value during the falling phase of the signal amplitude in the marker signal can be found in [reference needed]. Figure 11 As shown.

[0113] In one embodiment, determining the angle corresponding to the average value during the rising phase of the signal amplitude in the aforementioned S012 includes the following steps S121-S122:

[0114] S121. Determine the distance information corresponding to the average value during the rising phase of the signal amplitude in the signal of the marker. The distance information corresponding to the average value is the distance between the signal point with the average signal amplitude and the horizontal projection of the wafer center.

[0115] Specifically, the distance information corresponding to the average value during the rising phase of the signal amplitude in the marker signal can be determined based on the eddy current signal.

[0116] S122. Based on the distance information corresponding to the average value during the signal amplitude rise phase, determine the included angle corresponding to the average value during the signal amplitude rise phase in the marker's signal.

[0117] In one embodiment, determining the included angle of the marker signal based on the distance information corresponding to the average value during the signal amplitude rise phase includes: obtaining the distance between the horizontal projection of the polishing pad center and the horizontal projection of the wafer center; obtaining the distance between the horizontal projection of the polishing pad center and the intersection point; and calculating the included angle of the marker signal based on the distance information corresponding to the average value during the signal amplitude rise phase, the distance between the horizontal projection of the polishing pad center and the horizontal projection of the wafer center, and the distance between the horizontal projection of the polishing pad center and the intersection point.

[0118] In one embodiment, determining the angle corresponding to the average value during the decreasing phase of the signal amplitude in the aforementioned S012 includes the following steps S21-S22:

[0119] S21. Determine the distance information corresponding to the average value of the signal amplitude during the decreasing phase of the signal from the marker.

[0120] Specifically, distance information corresponding to the average value during the decreasing phase of the signal amplitude in the marker signal can be determined based on the eddy current signal.

[0121] S22. Based on the distance information corresponding to the average value during the signal amplitude decline phase, determine the included angle corresponding to the average value during the signal amplitude decline phase in the marker's signal.

[0122] In one embodiment, determining the included angle of the marker's signal based on the distance information corresponding to the average value during the signal amplitude decline phase includes: obtaining the distance between the horizontal projection of the polishing pad center and the horizontal projection of the wafer center; obtaining the distance between the horizontal projection of the polishing pad center and the intersection point; and calculating the signal included angle of the marker based on the distance information corresponding to the average value during the signal amplitude decline phase, the distance between the horizontal projection of the polishing pad center and the horizontal projection of the wafer center, and the distance between the horizontal projection of the polishing pad center and the intersection point.

[0123] S013. The average of the angles corresponding to the average value during the rising phase of the signal amplitude and the average value during the falling phase of the signal amplitude is taken as the signal angle of the marker.

[0124] In some embodiments, in S102, determining the angle deviation value between the signal angle and the actual angle between the marker includes: taking the difference between the signal angle and the actual angle between the marker as the angle deviation value.

[0125] When the signal angle is greater than the actual angle of the marker, the angle deviation value is positive; when the signal angle is less than the actual angle of the marker, the angle deviation value is negative.

[0126] In some embodiments, when the controller is used to perform the aforementioned step S103, i.e., to calibrate the wafer morphology feature signal according to the angle deviation value, it is specifically used to perform the following steps S1031-S1032:

[0127] S1031. Determine the deviation distance of the wafer morphology characteristic signal based on the angle deviation value;

[0128] Specifically, determining the deviation distance of the wafer morphology feature signal based on the angle deviation value may include: determining the deviation value of the distance from the intersection point to the horizontal projection of the wafer center based on the angle deviation value; and using the deviation value of the distance from the intersection point to the horizontal projection of the wafer center as the deviation distance of the wafer morphology feature signal.

[0129] S1032. Calibrate the wafer morphology feature signal according to the deviation distance.

[0130] In one embodiment, calibrating the wafer morphology feature signal based on the deviation distance includes: shifting the wafer morphology feature information accordingly based on the deviation distance to calibrate the wafer morphology feature signal.

[0131] The eddy current signal before calibration of the wafer morphology feature signal can be found in [reference]. Figure 12 As shown, the eddy current signal after calibration of the wafer morphology feature signal can be found in [reference needed]. Figure 13 As shown.

[0132] Furthermore, the changes in the degree of offset between the eddy current signal and the position signal before and after calibration of the wafer morphology feature signal can be found in [reference needed]. Figure 14 As shown.

[0133] In this application, by adding markers, the wafer morphology feature signals are calibrated using the marker signals contained in the eddy current signals. This achieves alignment between the position signal and the eddy current signal of the eddy current sensor, improving the synchronization between the position signal and the acquired eddy current signal. As the eddy current sensor rotates with the polishing disk, the signals acquired by the eddy current sensor in each rotation are synchronized signals. This results in higher accuracy of the wafer thin film thickness determined based on the synchronization between the position signal and the eddy current signal, and also makes the determination of the polishing endpoint and the dynamic adjustment of process parameters more accurate.

[0134] Please refer to Figure 15 , Figure 15 This is a schematic flowchart of a wafer fabrication method provided in an embodiment of the present application, which can be executed by the aforementioned controller. The method may include the following steps S501-S505:

[0135] S501, Control the wafer polishing assembly to polish the wafer;

[0136] S502. Acquire eddy current signals collected by the eddy current sensor during the wafer polishing process. The eddy current signals include: marker signals and wafer morphology feature signals.

[0137] S503. Determine the signal angle of the marker based on the marker signal. The signal angle is the angle between the first line connecting the horizontal projection of the polishing disk center and the horizontal projection of the wafer center and the second line connecting the two lines. The second line is the line connecting the intersection of the horizontal projection of the polishing disk center and the horizontal projection of the marker determined based on the marker signal and the horizontal projection of the circular trajectory.

[0138] S504. Determine the angular deviation between the signal angle and the actual angle between the marker;

[0139] S505. Calibrate the wafer morphology feature signal based on the angle deviation value;

[0140] Among them, the eddy current sensor is set on the polishing disk. During the wafer polishing process, the eddy current sensor forms a circular trajectory as the polishing disk rotates. The first line intersects with the horizontal projection of the circular trajectory, and the horizontal projection of the marker intersects with the horizontal projection of the circular trajectory. The position of the marker remains unchanged.

[0141] In some optional embodiments of this application, the determination of the signal angle of the marker based on the marker signal in S503 includes the following steps S51-S54:

[0142] S51. Determine the distance between the intersection point and the horizontal projection of the wafer center based on the peak value of the signal amplitude in the marker signal. The distance between the intersection point and the horizontal projection of the wafer center refers to the distance between the eddy current sensor and the horizontal projection of the wafer center when the eddy current sensor passes through the intersection point.

[0143] S52. Obtain the distance between the horizontal projection of the polishing pad center and the horizontal projection of the wafer center;

[0144] S53. Obtain the distance between the horizontal projection of the polishing disk center and the intersection point;

[0145] S54. Calculate the signal angle of the marker based on the distance between the intersection point and the horizontal projection of the wafer center, the distance between the horizontal projection of the polishing pad center and the horizontal projection of the wafer center, and the distance between the horizontal projection of the polishing pad center and the intersection point.

[0146] In one embodiment, the method further includes:

[0147] When the eddy current sensor detects that it has not detected a marker signal within a preset time period, or when the detected angular deviation value is greater than the preset deviation value range, the position of the marker is calibrated.

[0148] For details on the specific implementation of this embodiment, please refer to the foregoing content, which will not be repeated here.

[0149] Please refer to Figure 16 , Figure 16 This is a flowchart illustrating an embodiment of an eddy current monitoring method provided in this application. The method may include the following steps S601-S602:

[0150] S601 controls the relative motion between the wafer and the polishing pad;

[0151] S602. During the relative motion between the wafer and the polishing pad, an eddy current sensor mounted on the polishing pad monitors the eddy current signal, which includes a marker signal and a wafer morphology feature signal. The signal angle of the marker is determined based on the marker signal, and the angular deviation value between the signal angle and the actual angle of the marker is determined. The wafer morphology feature signal is calibrated based on the angular deviation value.

[0152] During the wafer polishing process, the eddy current sensor forms a circular trajectory as the polishing disk rotates. The first line connecting the horizontal projection of the polishing disk center and the horizontal projection of the wafer center intersects with the horizontal projection of the circular trajectory. The horizontal projection of the preset marker intersects with the horizontal projection of the circular trajectory, and the position of the marker remains unchanged.

[0153] The specific implementation method in this embodiment can be found in the foregoing content, and will not be repeated here.

[0154] This application also provides a chemical mechanical polishing apparatus, including: a polishing head, a polishing disc, and a liquid supply module, wherein an eddy current sensor is provided on the polishing disc, and a marker is provided on the liquid supply arm of the liquid supply module. The marker is used to enable the eddy current sensor to collect the marker signal, and the marker signal is used to calibrate the wafer morphology feature signal collected by the eddy current sensor.

[0155] In one embodiment, the surface of the marker is smooth; the marker is connected to the liquid supply arm and the connection is smoothly transitioned.

[0156] The specific implementation method in this embodiment can be found in the foregoing content, and will not be repeated here.

[0157] See Figure 17 , Figure 17 This is a schematic block diagram of an electronic device provided according to an embodiment of this application. Figure 17 The electronic device 900 in this embodiment may include one or more processors 901, one or more input devices 902, one or more output devices 903, and one or more memories 904. The processors 901, input devices 902, output devices 903, and memories 904 communicate with each other via a communication bus 905. The memory 904 stores computer programs, including program instructions. The processor 901 executes the program instructions stored in the memory 904. Specifically, the processor 901 is configured to invoke the program instructions to execute the steps in the methods described above.

[0158] It should be understood that, in the embodiments of this application, the processor 901 may be a central processing unit (CPU), or it may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0159] The memory 904 may include read-only memory and random access memory, and provides instructions and data to the processor 901. A portion of the memory 904 may also include non-volatile random access memory.

[0160] In specific implementations, the processor 901, input device 902, and output device 903 described in the embodiments of this application can execute the implementation methods described in the embodiments of this application, or they can execute the implementation methods of the electronic devices described in the embodiments of this application, which will not be repeated here.

[0161] In another embodiment of this application, a computer-readable storage medium is provided. This computer-readable storage medium stores a computer program, which includes program instructions. When executed by a processor, the program instructions implement all or part of the processes in the methods described above. Alternatively, the computer program can instruct related hardware to complete the process. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include any entity or device capable of carrying computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc.

[0162] The computer-readable storage medium can be an internal storage unit of the electronic device in any of the foregoing embodiments, such as a hard disk or memory of the electronic device. The computer-readable storage medium can also be an external storage device of the electronic device, such as a plug-in hard disk, smart media card (SMC), secure digital card (SD) card, flash card, etc., equipped on the electronic device. Furthermore, the computer-readable storage medium can include both internal and external storage units of the electronic device. The computer-readable storage medium is used to store computer programs and other programs and data required by the electronic device. The computer-readable storage medium can also be used to temporarily store data that has been output or will be output.

[0163] This application provides a computer program product, which includes computer-executable instructions or a computer program. The computer-executable instructions or computer program are stored in a computer-readable storage medium. The processor of an electronic device reads the computer-executable instructions from the computer-readable storage medium and executes the computer-executable instructions, causing the electronic device to perform the methods described in the embodiments of this application.

[0164] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this application.

[0165] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the electronic devices and units described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0166] In the several embodiments provided in this application, it should be understood that the disclosed electronic devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces or units, or it may be an electrical, mechanical, or other form of connection.

[0167] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of the embodiments of this application, depending on actual needs.

[0168] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0169] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A wafer fabrication system, characterized in that, include: Wafer polishing assembly, including a polishing disk for use as a wafer polishing base; An eddy current sensor is disposed on the polishing disk. During the wafer polishing process, the eddy current sensor forms a circular trajectory as the polishing disk rotates. The first line connecting the horizontal projection of the polishing disk center and the horizontal projection of the wafer center intersects the horizontal projection of the circular trajectory, and the horizontal projection of a preset marker intersects the horizontal projection of the circular trajectory. The position of the marker remains unchanged. The eddy current sensor is used to collect eddy current signals during the wafer polishing process. The eddy current signals include: marker signals and wafer morphology feature signals. The controller is configured to determine the signal angle of the marker based on the marker signal, wherein the signal angle is the angle between the first connecting line and the second connecting line, and the second connecting line is the line connecting the intersection of the horizontal projection of the polishing disk center and the horizontal projection of the marker determined based on the marker signal and the horizontal projection of the circular trajectory; determine the angular deviation value between the signal angle and the actual angle of the marker; calibrate the wafer morphology feature signal according to the angular deviation value; and control the wafer polishing assembly to polish the wafer.

2. The system as described in claim 1, characterized in that, When the controller is used to determine the signal angle of the marker based on the marker signal, it is specifically used for: The distance between the intersection point and the horizontal projection of the wafer center is determined based on the peak value of the signal amplitude in the marker signal; Obtain the distance between the horizontal projection of the center of the polishing pad and the horizontal projection of the center of the wafer; Obtain the distance between the horizontal projection of the center of the polishing pad and the intersection point; The signal angle of the marker is calculated based on the distance between the intersection point and the horizontal projection of the wafer center, the distance between the horizontal projection of the polishing pad center and the horizontal projection of the wafer center, and the distance between the horizontal projection of the polishing pad center and the intersection point.

3. The system as described in claim 1, characterized in that, When the controller is used to determine the signal angle of the marker based on the marker signal, it is specifically used for: Determine the average value of the signal amplitude in the marker signal; Determine the angle corresponding to the average value during the rising phase of the signal amplitude of the marker, and the angle corresponding to the average value during the falling phase of the signal amplitude; The average of the angle corresponding to the average value during the signal amplitude rise phase and the angle corresponding to the average value during the signal amplitude fall phase is taken as the signal angle of the marker.

4. The system as described in claim 1, characterized in that, When the controller is used to calibrate the wafer morphology feature signal according to the angle deviation value, it is specifically used for: The deviation distance of the wafer morphology feature signal is determined based on the angle deviation value; The wafer morphology feature signal is calibrated based on the deviation distance.

5. A wafer fabrication method, characterized in that, include: Control the wafer polishing assembly to polish the wafer; The eddy current signal collected by the eddy current sensor during the wafer polishing process is obtained. The eddy current signal includes: marker signal and wafer morphology feature signal. The signal angle of the marker is determined based on the marker signal. The signal angle is the angle between the first line connecting the horizontal projection of the polishing disk center and the horizontal projection of the wafer center, and the second line connecting the second line. The second line is the line connecting the intersection of the horizontal projection of the polishing disk center and the horizontal projection of the marker determined based on the marker signal and the horizontal projection of the circular trajectory. Determine the angular deviation between the signal angle and the actual angle between the marker and the object. The wafer morphology feature signal is calibrated based on the angle deviation value; The eddy current sensor is mounted on the polishing disk. During the wafer polishing process, the eddy current sensor rotates with the polishing disk to form a circular trajectory. The first connecting line intersects with the horizontal projection of the circular trajectory, and the horizontal projection of the marker intersects with the horizontal projection of the circular trajectory. The position of the marker remains unchanged.

6. The method as described in claim 5, characterized in that, Determining the signal angle of the marker based on the marker signal includes: The distance between the intersection point and the horizontal projection of the wafer center is determined based on the peak value of the signal amplitude in the marker signal; Obtain the distance between the horizontal projection of the center of the polishing pad and the horizontal projection of the center of the wafer; Obtain the distance between the horizontal projection of the center of the polishing pad and the intersection point; The signal angle of the marker is calculated based on the distance between the intersection point and the horizontal projection of the wafer center, the distance between the horizontal projection of the polishing pad center and the horizontal projection of the wafer center, and the distance between the horizontal projection of the polishing pad center and the intersection point.

7. The method as described in claim 5, characterized in that, The method further includes: When the eddy current sensor detects that it has not detected the marker signal within a preset time period, or when the angular deviation value is detected to be greater than a preset deviation value range, the position of the marker is calibrated.

8. A method for monitoring eddy currents, characterized in that, include: Controlling the relative motion between the wafer and the polishing pad; During relative motion between the wafer and the polishing pad, an eddy current sensor mounted on the polishing pad monitors eddy current signals, which include marker signals and wafer morphology feature signals. The system determines the signal angle of the marker based on the marker signals and determines the angular deviation between the signal angle and the actual angle of the marker. The wafer morphology feature signals are then calibrated based on the angular deviation. During wafer polishing, the eddy current sensor forms a circular trajectory as the polishing disk rotates. The first line connecting the horizontal projection of the polishing disk center and the horizontal projection of the wafer center intersects the horizontal projection of the circular trajectory, and the horizontal projection of a preset marker intersects the horizontal projection of the circular trajectory. The position of the marker remains unchanged. The signal angle is the angle between the first line and the second line, where the second line is the line connecting the intersection of the horizontal projection of the polishing disk center and the horizontal projection of the marker determined based on the marker signal with the horizontal projection of the circular trajectory.

9. A chemical mechanical polishing apparatus, characterized in that, A wafer processing system applicable to any one of claims 1-4 includes: a polishing head, a polishing disk, and a liquid supply module, wherein an eddy current sensor is disposed on the polishing disk, and a marker is disposed on the liquid supply arm of the liquid supply module, the marker being used to enable the eddy current sensor to acquire the marker signal, and the marker signal being used to calibrate the wafer morphology feature signal acquired by the eddy current sensor.

10. The apparatus as claimed in claim 9, characterized in that, The surface of the marker is smooth; the marker is connected to the liquid supply arm and the connection is smoothly transitioned.

11. An electronic device comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 5-7 or 8.

12. A computer storage medium, characterized in that, It stores a computer program that, when executed by a processor, implements the steps of the method as described in any one of claims 5-7 or 8.

13. A computer program product, characterized in that, Includes computer instructions that instruct a computing device to perform the steps of the method as described in any one of claims 5-7 or 8.

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