Wafer positioning device and method

Abstract

The present invention provides a wafer positioning device, wherein a controller receives image data of the wafer's outer edge and calculates the precise position of a positioning feature on the wafer's outer edge using the first-order and second-order derivatives of the image data in conjunction with a polynomial regression operation. After excluding the positioning feature from the image data, the center offset of the wafer is calculated based on the image data excluding the positioning feature, and then a correction angle and an X-Y correction amount are calculated. The controller then controls a drive device to rotate a rotary platform module based on the correction angle to rotate the positioning feature to a specified angle, and controls a drive device of the wafer positioning device based on the X-Y correction amount to move the wafer in the horizontal plane of the rotary platform module of the wafer positioning device so that the center of the wafer is aligned with the specified position of the rotary platform module.

Description

Technical Field

[0001] The present invention relates to a wafer positioning device and method, and in particular to a wafer positioning device and method that can detect non-transparent silicon wafers and semi-transparent wafers made of special materials and can support the judgment of different positioning characteristics. Background Art

[0002] Before the wafer enters the semiconductor manufacturing equipment, it needs to be positioned first. Therefore, the outer edge of the wafer will be designed with positioning features, such as notch-type positioning features. The wafer positioning device for wafer positioning is also called a wafer edge finder, and the wafer positioning device is mainly used to find the position of the positioning feature on the outer edge of the wafer (which is the angle of the positioning feature) and perform eccentricity correction (including correction of the XY correction amount (XY axis) and correction of the correction angle (θ axis)). After the wafer is corrected, its center will be aligned with the specified position of the rotating platform carrying the wafer, and the wafer will be rotated to the specified angle, and then the rotating platform carrying the wafer will send the wafer to the semiconductor manufacturing equipment for subsequent processes, where the specified position usually refers to the home position of the rotating platform, which is a fixed position, and when the wafer is scheduled to enter the next process, the positioning feature needs to be rotated to the specified angle.

[0003] Taiwan Patent No. TW I735315 provides a method and system for detecting wafer position. The detection method is described as follows: First, a rotating platform rotates in one direction at a relatively high speed to drive a wafer placed on the rotating platform and having an outer edge containing a positioning feature to rotate. Simultaneously, a detector detects the outer edge of the wafer and generates a detection result for a controller. Each detection result corresponds to a rotation angle of the rotating platform. After the positioning feature passes the detector, the rotating platform rotates in the opposite direction at a relatively slow speed to drive the wafer in the opposite direction. Simultaneously, the detector detects the outer edge of the wafer during the reverse rotation and generates a detection result for the controller. Finally, when the wafer's positioning feature passes the detector again, the rotating platform stops rotating. The controller estimates the wafer's eccentric position and the position of the positioning feature based on the accumulated detection results and the corresponding rotation angle.

[0004] However, the detection method of the aforementioned patent requires the rotating platform to rotate at least twice. Furthermore, according to the detailed description of the aforementioned patent, the wafers in the aforementioned patent cannot be translucent wafers, and the positioning features must be notched-type positioning features. Therefore, the industry still needs a wafer positioning device and method that can reduce the number of rotations of the rotating platform and can support various types of wafers and various types of positioning features. Summary of the Invention

[0005] In order to solve the above-mentioned technical problems, the present invention provides a wafer positioning device and method, which mainly calculates the first-order derivative and second-order derivative of the image data of the outer edge of the wafer to find the approximate position of the positioning feature on the outer edge of the wafer, and then calculates the precise position (i.e., the precise angle) of the positioning feature through polynomial regression. After that, after excluding the positioning feature from the image data, the center offset of the wafer is calculated based on the image data excluding the positioning feature. The correction angle is calculated based on the precise position of the positioning feature and the center offset, and the XY correction amount is calculated based on the correction angle and the center offset. Finally, the X-axis movement mechanism, Y-axis movement mechanism, and θ-axis rotation mechanism of the rotating platform are controlled based on the calculated correction angle and XY correction amount to align the center of the wafer with the specified position of the rotating platform and rotate the positioning feature of the wafer to the specified angle.

[0006] Based on at least one purpose of the present invention, the present invention provides a wafer positioning device, and the wafer positioning device includes a rotating platform module, a light source, an image capture device, a controller and a drive device. The rotating platform module is used to carry the wafer and to rotate the wafer. The light source is arranged on the outside of the rotating platform module and is used to emit light to illuminate the outer edge of the wafer. The image capture device is arranged on the outside of the rotating platform module and faces the light source, and is used to obtain image data of the outer edge of the wafer. The controller is electrically connected to the light source and the image capture device, and is used to receive the image data and calculate the precise position of the positioning feature on the outer edge of the wafer through the first-order derivative and second-order derivative of the image data combined with a polynomial regression operation. After excluding the positioning feature from the image data, the center offset of the wafer is calculated based on the image data excluding the positioning feature, the correction angle is calculated based on the precise position of the positioning feature and the center offset, and the XY correction amount is calculated based on the correction angle and the center offset. The drive device is electrically connected to the controller and connected to the rotating platform module. The controller controls the driving device to drive the rotating platform module to rotate according to the correction angle so that the positioning feature rotates to the specified angle (the positioning feature needs to be rotated to the specified angle when the wafer is scheduled to enter the next process), and the controller controls the driving device to drive the rotating platform module according to the XY correction amount so that the wafer moves in the horizontal plane of the rotating platform module so that the center of the wafer is aligned with the specified position of the rotating platform module (the specified position refers to the home position of the rotating platform module).

[0007] Optionally, in the embodiment of the above-mentioned wafer positioning device, the controller calculates the approximate position of the positioning feature based on the first-order derivative and the second-order derivative of the image data, and then performs multiple iterative calculations using polynomial regression operations based on the approximate position to calculate the precise position of the positioning feature, where the precise position is the precise angle of the positioning feature.

[0008] Optionally, in the above embodiment of the wafer positioning device, the controller excludes the positioning features at the precise positions in the image data, and finds the corresponding circle equation based on the image data excluding the positioning features to obtain the center offset.

[0009] Optionally, in the embodiment of the wafer positioning device, the wafer (WF) is a non-transparent silicon wafer or a wafer made of a semi-transparent material.

[0010] Optionally, in the embodiment of the wafer positioning device, the positioning feature of the wafer (WF) is a notch type positioning feature, a double flat edge type positioning feature, or a single flat edge type positioning feature.

[0011] Optionally, in the above-mentioned embodiment of the wafer positioning device, the controller controls the driving device to drive the rotating platform module to rotate at least 360 degrees, and the image data captured by the image capture device is image data of the outer edge of the wafer rotated at least 360 degrees.

[0012] Optionally, in the above-mentioned embodiment of the wafer positioning apparatus, the controller sets the brightness of the light source and the sensitivity of the image capture device according to instructions input by an operator, wherein the operator determines the input instructions according to the type of wafer.

[0013] Optionally, in the embodiment of the above-mentioned wafer positioning device, the rotating platform module includes a θ-axis rotation mechanism, a Y-axis movement mechanism and an X-axis movement mechanism, wherein the θ-axis rotation mechanism is used to be driven by a driving device to rotate the rotating platform module, and the Y-axis movement mechanism and the X-axis movement mechanism are used to be driven by the driving device to move the wafer in the horizontal plane of the rotating platform module.

[0014] Based on at least one purpose of the present invention, the present invention provides a wafer positioning method, which includes the following steps: starting a light source and an image capture module, wherein the light source and the image capture module are arranged relative to each other and face the outer edge of the wafer carried by the rotating platform module, and are located on the outside of the rotating platform module; using a controller to control a driving device to drive the rotating platform module to rotate at least 360 degrees, so as to drive the wafer carried by the rotating platform module to rotate at least 360 degrees; using an image capture device to obtain image data of the outer edge of the wafer; using a controller to calculate the approximate position of the positioning feature based on the first-order derivative and the second-order derivative of the image data, and then using a polynomial regression operation to perform multiple iterative calculations based on the approximate position to calculate the precise position of the positioning feature. position, wherein the precise position is the precise angle of the positioning feature; using a controller to exclude the positioning feature at the precise position in the image data, and finding the corresponding circle equation based on the image data excluding the positioning feature to obtain the center offset of the wafer; using the controller to calculate the correction angle based on the precise position of the positioning feature and the center offset, and calculating the XY correction amount based on the center offset and the correction angle; and using the controller to control the driving device to drive the rotating platform module to rotate according to the correction angle so that the positioning feature rotates to a specified angle, and using the controller to control the driving device to drive the rotating platform module according to the XY correction amount so that the wafer moves in the horizontal plane of the rotating platform module so that the center of the wafer is aligned with the specified position of the rotating platform module.

[0015] Optionally, in the embodiment of the wafer positioning method, the wafer is a non-transparent silicon wafer or a semi-transparent wafer, and the positioning feature of the wafer is a notch type positioning feature, a double flat edge type positioning feature or a single flat edge type positioning feature.

[0016] In summary, compared to prior art methods, the wafer positioning device and method of the present invention can reduce the number of rotations of the rotating platform and can support various types of wafers and various types of positioning features. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of a wafer positioning device according to an embodiment of the present invention.

[0018] Figure 2 It is a flowchart of a wafer positioning method according to an embodiment of the present invention.

[0019] Figure 3 It is a detailed flowchart of the steps of finding wafer positioning features and calculating the precise position and center offset of the wafer in the wafer positioning method according to an embodiment of the present invention.

[0020] Figure 4 FIG. 4 is a schematic diagram of a wafer correction angle in a wafer positioning method according to an embodiment of the present invention.

[0021] Figure 5 FIG. 4 is another schematic diagram of the wafer correction angle in the wafer positioning method according to an embodiment of the present invention.

[0022] Figure 6 FIG. 1 is a schematic diagram of XY correction amounts of a wafer in a wafer positioning method according to an embodiment of the present invention.

[0023] Figure 7 FIG. 4 is a schematic diagram of another XY correction amount of a wafer in the wafer positioning method according to an embodiment of the present invention.

[0024] Description of the figure number:

[0025] 1: Wafer positioning device

[0026] 11: Rotating platform module

[0027] 111: θ-axis rotation mechanism

[0028] 112: Y-axis moving mechanism

[0029] 113: X-axis moving mechanism

[0030] 12: Light Source

[0031] 13: Image capture device

[0032] 14: Controller

[0033] 15: Drive device

[0034] S21~S27, S251~S256: Steps

[0035] θ: Correction angle

[0036] θ a ,θ e ,θ b :angle

[0037] d: triangle height

[0038] D: Center offset

[0039] R: Radius

[0040] θ O : Exact location

[0041] θ t : Target angle

[0042] θ n : direction angle

[0043] WF: wafer. DETAILED DESCRIPTION

[0044] Please refer to Figure 1 , Figure 1 Figure 1 is a schematic diagram of a wafer positioning device according to an embodiment of the present invention. The wafer positioning device 1 includes a rotating platform module 11, a light source 12, an image capture device 13, a controller 14, and a drive device 15. In addition to being a rotatable platform for supporting the wafer WF, the rotating platform module 11 also includes a θ-axis rotation mechanism 111, a Y-axis movement mechanism 112, and an X-axis movement mechanism 113. The controller 14 is electrically connected to the light source 12, the image capture device 13, and the drive device 15. Furthermore, the θ-axis rotation mechanism 111, the Y-axis movement mechanism 112, and the X-axis movement mechanism 113 are electrically connected to the drive device 15.

[0045] The light source 12 is arranged at the lower outer side of the rotating platform module 11, and the image capture device 13 is arranged at the upper outer side of the rotating platform module 11, and the light source 12 and the image capture device 13 are arranged corresponding to each other. When the wafer WF is placed on the rotating platform module 11, the light emitted by the light source 12 will be directed to the outer edge of the wafer WF, and the image capture device 13 will capture the image data of the outer edge of the wafer WF. The light source 12 can be a laser diode or other directional light source, for example, a directional light source formed by a light-emitting diode and a convex lens. The image capture device 13 can be a charge coupled device (CCD) imaging device or other type of imaging device. In addition, the present invention does not limit the types of the light source 12 and the image capture device 13.

[0046] The controller 14 can rotate the θ-axis rotation mechanism 111 by controlling the drive device 15 (e.g., a drive motor or other type of actuator), thereby driving the platform of the rotating platform module 11 to rotate, causing the wafer WF carried by the rotating platform module 11 to rotate accordingly. In addition, the controller 14 can also control the Y-axis movement mechanism 112 and the X-axis movement mechanism 113 by controlling the drive device 15 to move the wafer WF carried by the rotating platform module 11 in the horizontal plane (XY axis plane) of the platform. The Y-axis movement mechanism 112 and the X-axis movement mechanism 113 can, for example, move the platform and the wafer WF in the horizontal plane (XY axis plane), and the θ-axis rotation mechanism 111 can be a central rotating shaft disposed below and connected to the platform. However, the present invention is not limited to the implementation method of the θ-axis rotation mechanism 111, the Y-axis movement mechanism 112, and the X-axis movement mechanism 113.

[0047] Furthermore, the controller 14 can also be used to set the intensity of the light source 12 and the sensitivity of the image capture device 13. In this way, the wafer positioning device 1 of the present invention can have a more precise positioning accuracy for different types of wafers WF. Please note that since the wafer positioning device 1 of the present invention mainly calculates the precise position of the positioning feature of the wafer WF (i.e., the precise angle of the positioning feature) through the first-order derivative and second-order derivative of the image data of the outer edge of the wafer in combination with a polynomial regression operation, the controller 14 is used to set the intensity of the light source 12 and the sensitivity of the image capture device 13 only to further improve the positioning accuracy, and this practice is not a necessary limitation of the present invention.

[0048] Please continue to Figures 1 to 3 , Figure 2 is a flow chart of a wafer positioning method according to an embodiment of the present invention, and Figure 3 This is a detailed flowchart illustrating the steps of finding the wafer positioning feature and calculating the precise position and center offset of the wafer positioning feature in a wafer positioning method according to an embodiment of the present invention. Controller 14 is typically a microcontroller unit capable of being programmed with firmware (although the present invention is not limited thereto and may also be implemented using pure hardware circuitry). The wafer positioning method of the present invention is primarily executed by controller 14.

[0049] In step S21, the light source 12 and the image capture device 13 are started. The wafer positioning device 1 of the present invention can support different types of wafers WF. The wafer WF can be a non-transparent silicon wafer or a translucent wafer of a special material. In order to improve the accuracy of positioning, in step S21, the operator can also input instructions into the controller 14 according to the type of wafer WF to set the intensity of the light source 12 and the sensitivity of the image capture device 13. Then, in step S22, the fixture will place the wafer WF on the platform of the rotating platform module 11. At this time, the center of the wafer WF may deviate from the specified position of the rotating platform module 11 (usually referred to as the home position), and the positioning feature has not yet turned to the specified angle when entering the next process. Therefore, the positioning device 4 is required to detect the wafer WF to position the wafer WF.

[0050] In step S23, the controller 14 controls the drive device 15 to drive the θ-axis rotation mechanism 111 to rotate the platform of the rotating platform module 11 from 360 degrees to 720 degrees, thereby allowing the image capture device 13 to obtain image data of the wafer WF outer edge in step S24. Next, in step S25, the controller 14 uses the obtained image data of the wafer WF outer edge to find the approximate position of the wafer WF's locating feature. The approximate position of the wafer WF's locating feature is found by first calculating the first and second derivatives of the wafer WF outer edge image data to eliminate center offset (i.e., XY offset). The approximate position of the wafer WF's locating feature is then determined by the rate of change of the first and second derivatives. Then, a polynomial regression operation is performed based on the approximate position to calculate the precise position of the locating feature through multiple iterations. The precise position of the locating feature is the angle of the locating feature. The locating feature is not limited to a notch-type locating feature and can also be a single flat edge, double flat edge, or other type of locating feature. In step S25 , the controller 14 excludes the positioning features at the precise positions in the image data, and finds the center offset based on the image data excluding the positioning features.

[0051] Then, in step S26, the controller 14 calculates the correction angle of the wafer WF based on the precise position of the positioning feature and the center offset, and calculates the XY correction amount based on the correction angle and the center offset. Finally, in step S27, the controller 14 corrects the wafer offset via the X-axis movement mechanism 113, the Y-axis movement mechanism 112, and the θ-axis rotation mechanism 111. Specifically, the controller 14 controls the drive device 15 to drive the θ-axis rotation mechanism 111 to rotate the platform based on the calculated correction angle of the wafer WF, thereby rotating the positioning feature of the wafer WF to a specified angle. The controller 14 also controls the drive device 15 to drive the Y-axis movement mechanism 112 and the X-axis movement mechanism 113 to move the wafer WF in the horizontal plane based on the calculated XY correction amount, thereby aligning the center of the wafer WF with the specified position of the platform.

[0052] In step S24, the controller 14 also checks whether the image data index is continuous and the angular difference between the wafer WF before and after rotation. If the image data index is not continuous (because if the rotation speed is too fast, image data may be missing, so this check is necessary) or the angular difference between the wafer WF before and after rotation is less than 360 degrees (because the platform of the rotation platform module 11 may not rotate more than 360 degrees due to an operational error or other factors), steps S23 and S24 must be performed again to re-acquire valid image data of the wafer WF outer edge.

[0053] Furthermore, if Figure 3Step S25 includes steps S251 to S256. In step S251, the controller 14 performs a moving average on the image data to filter out most of the noise in the image data. Please note that step S251 is not a required step, but in most cases, it is performed to increase positioning accuracy. Next, in step S252, the controller 14 calculates the first and second derivatives of the image data. The first derivative of the image data is the slope function of the image data. Where the slope function is 0, it is likely where the extreme value occurs, which is the possible location of the positioning feature. The second derivative of the image data can be used to determine where the slope changes the most. Typically, the location of the positioning feature occurs where the slope changes the most. Furthermore, before performing step S252, the controller 14 can first check whether the brightness setting of the light source 12, the sensitivity setting of the image capture device 13, and the angular difference before and after the platform rotation are correct to avoid unnecessary calculations.

[0054] In step S253, the controller 14 determines the maximum and minimum values ​​of the first-order derivative of the image data. In step S253, the controller 14 also determines whether the rotation angles corresponding to the maximum and minimum values ​​of the first-order derivative are similar, that is, whether the difference between the two locations where the maximum and minimum values ​​of the first-order derivative occur is less than a specified threshold. Only if the rotation angles corresponding to the maximum and minimum values ​​of the first-order derivative are similar will further calculations be performed. In step S253, the controller 14 also checks whether the maximum and minimum values ​​of the image data are out of range. If so, subsequent calculations are not performed.

[0055] Next, in step S254, the controller 14 uses the second-order derivative and the first-order derivative of the image data to find the approximate location of the locating feature. Furthermore, the maximum and minimum values ​​of the first-order derivative found previously may be the locations of the greatest change in the image data. Therefore, the locations of the maximum and minimum values ​​of the first-order derivative can be used to narrow the range for searching for the locating feature. Simply put, the controller 14 uses the first-order derivative of the image data to narrow the range for searching for the locating feature, and then uses the second-order derivative of the image data to find the approximate location of the locating feature within this narrowed range.

[0056] Next, in step S255, the controller 14 performs multiple iterative calculations using a polynomial regression operation based on the approximate position of the locating feature to determine the precise position of the locating feature (including the angle of the locating feature). Then, in step S256, the controller 14 excludes the portion of the locating feature at the precise position from the image data and finds the corresponding circle equation based on the image data excluding the locating feature to obtain the center offset of the wafer WF.

[0057] The polynomial regression operation in step S255 is described as follows: The approximate position θ of the positioning feature can be obtained by calculating the first and second derivatives of the image data. coarse , and the difference Diff between the maximum and minimum values ​​near the approximate position in the image data can also be calculated. Furthermore, when the positioning feature falls on the approximate position θ coarse When the wafer WF center point and the specified position (home position) are offset D coarse It is known that the approximate position of the positioning feature θ coarse The image value CCD is also known, and the radius R of the wafer WF is also known, so the following expression is used:

[0058] ccd=Diff+D coarse *cos(θ O )-[R 2 -D coarse 2 *sin 2 (θ O )] 1 / 2 , and find the exact position θ of the positioning feature O In the present invention, the number of iterations is 1000, but the present invention is not limited to this. Next, the precise position θ of the positioning feature is calculated. O After that, the controller 14 can exclude the positioning features of the precise position in the image data, find the corresponding circle equation based on the image data excluding the positioning features, and calculate the center offset D.

[0059] After calculating the exact position of the positioning feature θ O The correction angle θ and the XY correction amount D are calculated in step S26. x 、D y The details are as follows, supplementary explanation, D x is the X-axis correction component of the correction amount D, D y It is the Y-axis correction component of the correction amount D. Please refer to Figure 4 and Figure 5 , the radius R of the wafer WF, the center offset D, and the precise position of the positioning feature θ O (precise angle), target angle θ of the positioning feature relative to the horizontal axis of the wafer WF center point t and the orientation angle θ of the positioning feature n is known, so we can calculate θ a =θ O -θ n , d=D*sin(θ a ) and θ e =θ b =sin -1(d / R), without considering the error caused by the positioning characteristics of the notch type, the correction angle θ can be calculated as t -θ n +θ e Next, please refer to Figure 6 Then, the XY correction amount D can be calculated based on the correction angle θ and the center offset x =D*cos(θ+θ O ) and D y =D*sin(θ+θ O ). Figures 4 to 6 The calculation is for the positioning feature of the notch type, but the present invention does not limit the type of positioning feature. Please refer to Figure 7 , the correction angle θ and XY correction amount D of the positioning feature of the single flat edge type x 、D y The calculation method and the correction angle θ and XY correction amount D of the positioning feature of the notch type x 、D y The calculation method is the same, but θ e will be equal to 0, so the correction angle θ=θ t -θ n .

[0060] In summary, because the wafer positioning apparatus and method provided by the present invention primarily locates positioning features through the combination of first- and second-order derivatives of wafer periphery image data with polynomial regression, there is no need for the rotary platform to rotate more than twice, and there are no restrictions on the type of wafer or positioning features. In other words, compared to prior art methods, the wafer positioning apparatus and method of the present invention can achieve a lower number of rotary platform rotations and support various types of wafers and positioning features.

Claims

1. A wafer positioning device, characterized in that: include: a rotating platform module (11) for carrying a wafer (WF) and for rotating to rotate the wafer (WF); a light source (12) disposed on an outer side of the rotating platform module (11) and configured to emit light to illuminate an outer edge of the wafer (WF); an image capturing device (13), disposed on the outer side of the rotating platform module (11) and facing the light source (12), for acquiring image data of the outer edge of the wafer (WF); a controller (14) electrically connected to the light source (12) and the image capture device (13), for receiving the image data, and calculating a precise position of a positioning feature of the outer edge of the wafer (WF) through a first-order derivative and a second-order derivative of the image data in conjunction with a polynomial regression operation, excluding the positioning feature from the image data, calculating a center offset of the wafer (WF) based on the image data excluding the positioning feature, calculating a correction angle based on the precise position of the positioning feature and the center offset, and calculating an XY correction value based on the center offset and the correction angle; and A driving device (15) is electrically connected to the controller (14) and the rotating platform module (11), wherein the controller (14) controls the driving device (15) to drive the rotating platform module (11) to rotate according to the correction angle so that the positioning feature rotates to a specified angle, and the controller (14) controls the driving device (15) to drive the rotating platform module (11) according to the XY correction amount so that the wafer (WF) moves in a horizontal plane of the rotating platform module (11) so that a center of the wafer (WF) is aligned with a specified position of the rotating platform module (11).

2. The wafer positioning device according to claim 1, wherein: The controller (14) calculates an approximate position of the positioning feature based on the first-order derivative and the second-order derivative of the image data, and then performs multiple iterative calculations using the polynomial regression operation based on the approximate position to calculate a precise position of the positioning feature, wherein the precise position is a precise angle of the positioning feature.

3. The wafer positioning device according to claim 2, wherein: The controller (14) excludes the positioning feature of the precise angle in the image data and finds a corresponding circle equation based on the image data excluding the positioning feature to obtain the center offset.

4. The wafer positioning device according to claim 1, wherein: The wafer (WF) is a non-transparent silicon wafer or a wafer made of a semi-transparent material.

5. The wafer positioning device according to claim 1, wherein: The positioning feature of the wafer (WF) is a notch type positioning feature, a double flat edge type positioning feature, or a single flat edge type positioning feature.

6. The wafer positioning device according to claim 1, wherein: The controller (14) controls the driving device (15) to drive the rotating platform module (11) to rotate at least 360 degrees, and the image data captured by the image capture device (13) is image data of the outer edge of the wafer (WF) rotating at least 360 degrees.

7. The wafer positioning device according to claim 1, wherein: The controller (14) sets the brightness of the light source (12) and the sensitivity of the image capture device (13) according to an instruction input by an operator, wherein the operator determines the input instruction according to a type of the wafer (WF).

8. The wafer positioning device according to claim 1, wherein: The rotating platform module (11) includes a θ-axis rotating mechanism (111), a Y-axis moving mechanism (112) and an X-axis moving mechanism (113), wherein the θ-axis rotating mechanism (111) is used to be driven by the driving device (15) to rotate the rotating platform module (11), and the Y-axis moving mechanism (112) and the X-axis moving mechanism (113) are used to be driven by the driving device (15) to move the wafer (WF) in the horizontal plane of the rotating platform module (11).

9. A wafer positioning method, characterized in that: include: activating a light source (12) and an image capturing module (13), wherein the light source (12) and the image capturing module (13) are disposed opposite to each other and face an outer edge of a wafer (WF) carried by the rotating platform module (11), and are located outside a rotating platform module (11); Using a controller (14) to control a driving device (15) to drive the rotating platform module (11) to rotate at least 360 degrees, so as to drive the wafer (WF) carried by the rotating platform module (11) to rotate at least 360 degrees; Using the image capture device (13) to acquire image data of the outer edge of the wafer (WF); The controller (14) is used to calculate an approximate position of a positioning feature according to a first-order derivative and a second-order derivative of the image data, and then a polynomial regression operation is used to perform multiple iterative calculations according to the approximate position to calculate an accurate position of the positioning feature, wherein the accurate position is an accurate angle of the positioning feature; Using the controller (14) to exclude the positioning feature of the precise angle in the image data, and finding a corresponding circle equation based on the image data excluding the positioning feature to obtain a center offset of the wafer (WF); Using the controller (14) to calculate a correction angle according to the precise position of the positioning feature and the center offset, and to calculate an XY correction amount according to the correction angle and the center offset; and The controller (14) is used to control the driving device (15) according to the correction angle to drive the rotating platform module (11) to rotate so that the positioning feature rotates to a specified angle, and the controller (14) is used to control the driving device (15) according to the XY correction amount to drive the rotating platform module (11) so that the wafer (WF) moves in a horizontal plane of the rotating platform module (11) so that a center of the wafer (WF) is aligned with a specified position of the rotating platform module (11).

10. The wafer positioning method according to claim 9, wherein: The wafer (WF) is a non-transparent silicon wafer or a wafer made of a translucent material, and the positioning feature of the wafer (WF) is a notch type positioning feature, a double flat edge type positioning feature or a single flat edge type positioning feature.

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