A sensor setting method for wafer detection

Abstract

The application relates to the technical field of semiconductor detection, and provides a sensor setting method for wafer detection, which comprises the following steps: S1, acquiring the angle range and the range range of a sensor; S2, acquiring a wafer edge contour type; S3, according to the wafer edge contour type and the angle range of the sensor, dividing the angle measurement range of each sensor and determining the angle posture of each sensor; S4, according to the wafer edge contour type and the range range of the sensor, dividing the range measurement range of each sensor; and S5, determining the number of sensors according to the angle measurement range and the range measurement range of each sensor. The application can set the sensors according to different wafer edge contour types, so that the minimum number of sensors capable of covering the whole wafer edge contour is determined, the sensors are accurately set, and the detection cost and the production cost are reduced to a certain extent.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor detection, and in particular relates to a sensor setting method for wafer detection. Background Art

[0002] During semiconductor wafer processing, the surface quality and edge quality of the wafer are key factors affecting chip performance and yield, so they need to undergo multiple rigorous inspections to ensure that there are no defects. Currently, edge detection mainly uses optical cameras (such as area array cameras or line scan cameras) in conjunction with specific light sources (such as ring lights or side lighting) to capture wafer edge images, and then uses image processing algorithms to identify information such as defect location, type, and size. However, due to the limitations of resolution and two-dimensional detection capabilities of optical imaging, it is difficult to accurately restore the three-dimensional morphology of the edge, especially defects such as micron-level chipping, cracks, or contamination. In addition, factors such as light source angle, reflection interference, and edge chamfer structure may lead to insufficient image contrast or morphological distortion, affecting the accurate assessment of defects.

[0003] When constructing three-dimensional morphology, some existing technologies use contact probes for detection, which can easily cause damage to the wafer. Some use an optical camera combined with a line structured light sensor for detection. This method is not accurate enough for three-dimensional morphology detection of wafers. Because the three-dimensional morphology detection of the wafer edge contour has certain particularities, high precision is the primary criterion. Moreover, the wafer edge contour has different shape types. For the three-dimensional morphology detection of different types of wafer edge contours, it is difficult to select sensors and set them reasonably and accurately.

[0004] In order to solve the above technical problems, the present invention designs a sensor setting method for wafer detection. Summary of the Invention

[0005] The present invention provides a sensor setting method for wafer detection, which aims to ensure that the total detection range of the set sensors can cover the entire wafer edge contour to detect contour data and restore the contour morphology. In addition, the sensors can be set according to different wafer edge contour types to determine the minimum number of sensors that can cover the entire wafer edge contour, accurately set the sensors, and reduce the detection cost and production cost to a certain extent.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a sensor setting method for wafer detection, comprising the following steps: S1, obtaining the angle range and range of the sensor; S2, obtaining the wafer edge profile type; S3, dividing the angle measurement range of each sensor according to the wafer edge profile type and the angle range of the sensor, and determining the angle posture of each sensor; S4, dividing the range measurement range of each sensor according to the wafer edge profile type and the range of the sensor; S5, determining the number of sensors according to the angle measurement range and range measurement range of each sensor.

[0007] Furthermore, in step S1, the angle range of the sensor is α, the error coefficient is set to ρ, the value range of ρ is (0, 1], the range of the sensor is L, the error coefficient is set to k, and the value range of k is (0, 1).

[0008] Optionally, in step S2, the wafer edge profile types include A-type profile, B-type profile, C-type profile and special-shaped profile.

[0009] Based on the above technical solution, step S3 includes the following steps: S3.1, obtaining a change curve 1 of the angle between the tangent corresponding to each point of the wafer edge contour line and the wafer radial direction; S3.2, dividing the total measurement angle range of the change curve 1 in sequence according to the angle range of the sensor to obtain the angle measurement range of each sensor; S3.3, determining the angle posture of each sensor and the first number of sensors based on the angle measurement range of each sensor.

[0010] Furthermore, in step S3.2, when dividing the angle measurement range of the sensor, the end point of the angle measurement range of a sensor coincides with the starting point of the angle measurement range of an adjacent sensor.

[0011] Optionally, in step S3.2, when dividing the angle measurement range of the sensor, an overlapping range is formed between the angle measurement range of the sensor and the angle measurement range of an adjacent sensor.

[0012] Based on the above technical solution, step S4 includes the following steps: S4.1, obtaining a second change curve of the distance between each point on the wafer edge contour line and the upper surface of the wafer; S4.2, setting the initial distance between the sensor and the wafer surface, and dividing it in sequence according to the sensor's range and the total measurement range of the change curve 2 to obtain the range measurement range of each sensor; S4.3, determining the second number of sensors based on the range measurement range of each sensor.

[0013] Based on the above technical solution, step S5 includes the following steps: S5.1, determining the set number of sensors based on the first number and the second number; S5.2, when the first number is equal to the second number, the set number of sensors is the first number or the second number; when the first number is greater than the second number, the set number of sensors is the first number, and when the first number is less than the second number, the set number of sensors is the second number.

[0014] Furthermore, the step S5 also includes the following steps: S5.3, when the first number is greater than the second number, adjusting the distance between the end sensor and the adjacent sensor and the wafer surface, so that the end sensor and the adjacent sensor divide the original range measurement range of the adjacent sensor according to a preset ratio; when the first number is less than the second number, adjusting the angular posture of the end sensor and the adjacent sensor, so that the end sensor and the adjacent sensor divide the original angle measurement range of the adjacent sensor according to a preset ratio.

[0015] Compared with the related art, the present invention has the following beneficial effects:

[0016] The present invention divides the angle measurement ranges of multiple sensors in sequence according to the wafer edge profile type and the angle range of the sensor, determines the angle posture of the sensor and the first number of sensors according to the angle measurement range of each sensor, divides the range measurement ranges of multiple sensors in sequence according to the wafer edge profile type and the range of the sensor, determines the second number of sensors according to the range measurement range of each sensor, and determines the final number of sensors to be set according to the first number and the second number. In this way, the number, angle posture and measurement range of the sensors are determined, and the sensors are set accordingly, which improves the accuracy and efficiency of subsequent detection to a certain extent. In addition, the sensors can be set according to different wafer edge profile types to determine the minimum number of sensors that can cover the entire wafer edge profile range, accurately set the sensors, and reduce the detection cost and production cost to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only one embodiment of the present invention. Those skilled in the art can also derive other implementation drawings based on the provided drawings without inventive effort.

[0018] Figure 1 It is a flow chart of the sensor setting method provided by the present invention;

[0019] Figure 2is a schematic diagram of the angular range and measuring range of the sensor provided by the present invention;

[0020] Figure 3 It is a structural schematic diagram of the moving direction of the sensor provided by the present invention;

[0021] Figure 4 Schematic diagram of the angle variation curve corresponding to the A-shaped profile of the wafer edge provided by the present invention;

[0022] Figure 5 Schematic diagram of the angle variation curve corresponding to the B-type profile of the wafer edge provided by the present invention;

[0023] Figure 6 Schematic diagram of the angle variation curve corresponding to the wafer edge profile provided by the present invention;

[0024] Figure 7 Schematic diagram of the angle variation curve corresponding to the A-type profile provided by the present invention when there is an overlap in the angle measurement ranges of adjacent sensors;

[0025] Figure 8 Schematic diagram of a distance variation curve between a point on a contour line corresponding to the A-shaped contour of a wafer edge and the upper surface of the wafer provided by the present invention;

[0026] Figure 9 Schematic diagram of a distance variation curve between a point on a contour line corresponding to a B-shaped contour of a wafer edge and the upper surface of the wafer provided by the present invention;

[0027] Figure 10 Schematic diagram of a distance variation curve between a point on a contour line corresponding to a wafer edge profile provided by the present invention and the upper surface of the wafer;

[0028] Figure 11 Schematic diagram of the measuring range of the sensor provided by the present invention;

[0029] Figure 12 is a schematic diagram of the measurement range when the first number and the second number of sensors provided by the present invention are equal;

[0030] Figure 13 is a schematic diagram of the present invention before the measurement range is adjusted when the first number of sensors is greater than the second number;

[0031] Figure 14 is a schematic diagram of the measurement range after adjustment when the first number of sensors provided by the present invention is greater than the second number;

[0032] Figure 15 This is a schematic diagram of the measurement range when the angle measurement range and the range measurement range of the sensor provided by the present invention have overlapping parts. DETAILED DESCRIPTION

[0033] The present invention will be further described below with reference to the accompanying drawings and examples:

[0034] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0035] In the description of the present invention, it should be noted that, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections or indirect connections through an intermediary. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0036] In the description of the present invention, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0037] In the present application, the sensor is a spectral confocal sensor. On the basis of the confocal sensor, the spectral confocal sensor uses the positional chromatic aberration of the objective lens to focus the monochromatic light of different wavelengths in the polychromatic light on different axial positions, so as to achieve a one-to-one correspondence between wavelength and position. When there is a measured object, the measuring light is reflected back after being irradiated on the surface of the measured object. At this time, only the monochromatic light focused on the surface of the measured object meets the confocal condition, and most of its energy can be detected by the spectrometer through the confocal aperture, while the rest of the monochromatic light in the defocused state on the surface of the measured object is blocked by the confocal aperture and cannot be detected by the spectrometer. Then in the spectral signal, the peak wavelength corresponds to the wavelength of the monochromatic light focused on the surface of the measured object, thereby determining the distance between the spectral confocal sensor and the measured point of the measured object at this time, moving the spectral confocal sensor, obtaining the distance information between multiple measured points and the sensor, analyzing and processing the distance information, and obtaining the surface morphology of the measured object.

[0038] Combine Figure 1 As shown, the embodiment of the present disclosure discloses a sensor setting method for wafer detection, comprising the following steps:

[0039] S1, obtain the angle range and measuring range of the sensor;

[0040] S2, obtaining the wafer edge profile type;

[0041] S3, dividing the angle measurement range of each sensor according to the wafer edge profile type and the angle range of the sensor, and determining the angle posture of each sensor;

[0042] S4, dividing the measurement range of each sensor according to the wafer edge profile type and the sensor range;

[0043] S5, determining the number of sensors according to the angle measurement range and the range measurement range of each sensor.

[0044] In the embodiment of the present disclosure, in step S1, the sensor is a spectral confocal sensor. The spectral confocal sensor has a fixed angle range and range during the detection process. The angle range of the sensor is obtained as α. To ensure the measurement accuracy, the error coefficient is set to ρ. The value range of ρ is (0, 1]. The precise angle range of the sensor is ρα. Preferably, ρ=0.8. Figure 2 As shown, the reference plane of the sensor is set to L0, the range of the sensor measurement is L, and to ensure the measurement accuracy, the error coefficient is set to k, the value range of k is (0, 1), preferably, k=0.9, and the precise range of the sensor is L0+kL.

[0045] like Figure 3 As shown, during the detection process, the moving direction of each sensor is perpendicular to the axial direction of the sensor. For example, the sensor arranged perpendicular to the upper or lower surface of the wafer, that is, the vertically arranged sensor, moves in a horizontal direction; the sensor arranged along the radial direction of the wafer, that is, the horizontally arranged sensor, moves in a vertical direction.

[0046] Among them, the spectral confocal sensor is limited by its own angular range during the detection of the wafer edge profile. During detection, it is necessary to determine whether the angle between the tangent at the detection point on the corresponding wafer edge profile and the side of the wafer close to the wafer in the radial direction is within the angular range of the sensor. If the angle is within the angular range of the sensor, it can be detected normally. If the angle exceeds the angular range of the sensor, it cannot be detected.

[0047] Based on the above technical solution, step S3 includes the following steps: S3.1, obtaining a change curve 1 of the angle between the tangent corresponding to each point of the wafer edge contour line and the wafer in the radial direction; S3.2, dividing the total measurement range of the change curve 1 in sequence according to the angle range of the sensor to obtain the angle measurement range of each sensor; S3.3, determining the angle posture of each sensor and the first number of sensors based on the angle measurement range of each sensor.

[0048] (1) In step S3.1, Figure 4-6 As shown, it is a curve of the change of the angle between the tangent line corresponding to each point of the wafer edge contour line of different types and the wafer radial direction, with the sequential sampling points of the wafer edge contour as the x-axis and the angle between the tangent line corresponding to the sequential sampling points and the side of the wafer close to the wafer in the radial direction as the y-axis.

[0049] The wafer edge profile types include type A, type B, type C and special shapes, among which the type A profile is an arc surface, the type B profile is a combination of an arc chamfer and a vertical surface, and the type C profile is similar to the type B profile, the only difference being the length of the vertical surface. The description of the type C profile is omitted in this embodiment. The special-shaped profile is formed when multiple type A, type B or type C wafers are bonded, and may form wafer edge profiles such as step surfaces.

[0050] Wafer A-type profile: Figure 4 As shown, when the first sensor is set vertically toward the upper surface of the wafer, the intersection of the axis of the first sensor and the upper surface of the wafer is the origin O, and the clockwise rotation is the positive direction. The angle between the tangent line of each point corresponding to the wafer edge contour line in the clockwise direction and the wafer radial direction is β. The variation curve of β is shown in Figure 4 As shown in the figure, β gradually increases from 0° to 90°, and from 90° to 180°. The value range of β is (0°, 180°).

[0051] Wafer B-type profile: Starting from the origin O on the wafer edge contour line, the change curve of the angle β between the tangent line of each corresponding point in the clockwise direction and the wafer radial direction is as follows: Figure 5 As shown, the difference compared with the A-type profile is that it gradually increases from 0° to 90°, maintains a certain distance at 90°, and then gradually increases from 90° to 180°. The value range of β is (0°, 180°).

[0052] Wafer profile: β change curve is as follows Figure 6 As shown in the figure, β gradually increases from 0° to 90°, maintains a certain distance at 90°, then gradually decreases from 90° to 0°, maintains a certain distance at 0°, then gradually increases from 0° to 90°, maintains a certain distance at 90°, then gradually decreases from 90° to 0°, maintains a certain distance at 0°, then gradually increases from 0° to 90°, and then gradually increases from 90° to 180°. The value range of β is (0°, 180°).

[0053] In steps S3.2 and S3.3, the angle measurement range and the angle posture of each sensor are determined:

[0054] When the angular range of all sensors is ρα, the angular measurement range of the first sensor is (0, ρα).

[0055] When the end point of the first sensor's angular measurement range is the start point of the second sensor's angular measurement range, the second sensor's angular measurement range is (ρα, 2ρα). Similarly, the angular measurement range of the Nth sensor is ((N-1)*ρα, 180°). At this point, the angle between the axis of the second sensor and the axis of the first sensor is γ, where γ = ρα.

[0056] The angular attitude of each sensor is the median of the sensor's angular measurement range. Therefore, the angular attitude of the first sensor is ρα / 2, the angular attitude of the second sensor is 3ρα / 2, and the angular attitude of the Nth sensor is ((N-1)*ρα+180°) / 2.

[0057] In order to ensure the accuracy of measurement and avoid the problem of ambiguity when the sensor detects at the end of the angle measurement range, the angle measurement ranges of adjacent sensors can be overlapped. When the angle measurement ranges of adjacent sensors have overlapping parts, the preset overlapping part is b% of the angle range of the corresponding sensor, such as Figure 7 As shown in the figure, the angle measurement range of the first sensor is (0, ρα), the angle measurement range of the second sensor is (ρα*(1-b%), ρα*(1-b%)+ρα), and the angle measurement range of the Nth sensor is (Nρα-(N-1)ρα*(1-b%), 180°). At this time, the angle between the axis of the second sensor and the axis of the first sensor is γ, where γ = ρα.

[0058] The angular attitude of each sensor is the median of the angular measurement range of the sensor. Therefore, the angular attitude of the first sensor is ρα / 2, the angular attitude of the second sensor is ρα*b%+3ρα / 2, and the angular attitude of the Nth sensor is (Nρα-(N-1)ρα*(1-b%)+180°) / 2.

[0059] When the angle range of the first sensor is ρα1, the angle range of the second sensor is ρα2, and the angle range of the Nth sensor is ρα n When the angle measurement range of each sensor is adjusted accordingly, it will not be described in detail here.

[0060] In addition, after obtaining the angular posture of the sensor and the angle between it and the adjacent sensors, when setting the sensor subsequently, one can determine its position by the angular posture of the sensor, and the other can determine its position by the angle between the sensor and the adjacent sensors. The two can verify each other and improve the accuracy of sensor setting.

[0061] In step S3.3, the first number of sensors is determined:

[0062] like Figure 4As shown, taking wafer A profile as an example, the total y-axis measurement range is divided according to the angular measurement range of each sensor, so that the angular measurement ranges of the multiple sensors completely cover (0°, 180°). This determines the first number of sensors. Taking α = 60° and ρ = 0.8 as an example, the angular measurement ranges of the multiple sensors are (0°, 48°), (48°, 96°), (96°, 144°), and (144°, 180°), respectively. In this case, the first number of sensors is 4.

[0063] The division method corresponding to the wafer B-type profile is the same as the division method of the wafer A-type profile, and the first number of sensors determined is the same, such as Figure 5 shown.

[0064] The division method of wafer profile is the same as that of A-type and B-type profile, but the first number of sensors is different. Figure 6 As shown, taking α = 60° and ρ = 0.8 as an example, the angle measurement ranges of multiple sensors are (0°, 48°), (48°, 96°) in sequence. Figure 6 The first platform appears at 90°, so the angle measurement range of the second sensor is (48°, 90°), followed by (90°, 42°), (42°, 0°), (0°, 48°), (48°, 90°), (90°, 42°), (42°, 0°), (0°, 48°), (48°, 96°), (96°, 144°), (144°, 180°), and the first number of sensors is 12.

[0065] Based on the above technical solution, step S4 includes the following steps: S4.1, obtaining a second change curve of the distance between each point on the wafer edge contour line and the upper surface of the wafer; S4.2, setting the initial distance between the sensor and the wafer surface, and dividing it in sequence according to the sensor's range and the total measurement range of the change curve 2 to obtain the range measurement range of each sensor; S4.3, determining the second number of sensors based on the range measurement range of each sensor.

[0066] (2) In step 4.1, Figure 7-9 As shown, it is a second curve of the change of the distance between each point on the edge contour line of different types of wafers and the upper surface of the wafer, with the sequential sampling points of the wafer edge contour as the x-axis and the distance between the sequential sampling points and the upper surface of the wafer as the y-axis.

[0067] Wafer A-type profile: Figure 8As shown, when the first sensor is set vertically toward the upper surface of the wafer, the intersection of the axis of the first sensor and the upper surface of the wafer is the origin O, and the clockwise rotation is the positive direction. The distance between each corresponding point along the wafer edge contour line in the clockwise direction and the upper surface of the wafer is S, and the variation curve of S is shown in FIG. Figure 8 As shown, the distance between the upper and lower surfaces of the wafer is L S , S gradually increases from 0 to L S The value range of S is (0, L S ).

[0068] Wafer B-type profile: The distance S between each point on the wafer edge contour line and the wafer top surface is a changing curve as shown in Figure 2. Figure 9 As shown, the difference compared with the A-type profile is that S gradually increases from 0 and increases rapidly within a certain distance until it increases to L S The value range of S is (0, L S ).

[0069] Wafer profile: Figure 10 As shown, S gradually increases from 0, and increases rapidly within a certain distance until it increases to L S , and then by L S Gradually increase, increasing rapidly over a certain distance until it reaches 2L S , then by 2L S Gradually increase, increasing rapidly over a certain distance until it reaches 3L S It no longer changes after that.

[0070] In step S4.2, the distance between the reference plane L0 and the wafer surface when the sensor is in the initial position is set to l 1. In this embodiment l 1 is 0, that is, the reference plane of the sensor in the initial position coincides with the upper surface of the wafer to determine the range measurement range of each sensor:

[0071] Take the A-type profile as an example, Figure 11 As shown, when the measuring range of the first sensor is kL1, the measuring range of the second sensor is kL2, and the measuring range of the Nth sensor is kL N When the range of the first sensor is (0, kL1), the corresponding range of the wafer edge contour line is (O, O1), the range of the second sensor is (kL1, kL1+kL2), the corresponding range of the wafer edge contour line is (O1, O2) and the range of the Nth sensor is (kL1+…+kL N , L S ), the corresponding wafer edge contour line range is (O N-1 , O N).

[0072] In step S4.3, the second number of sensors is determined:

[0073] Take the A-type profile as an example, Figure 8-11 As shown, the variation curve is divided into two parts according to the range measurement range of each sensor to determine the second number of sensors. The steps are as follows: the detection starting point of the first sensor is set to O, that is, the reference plane of the first sensor is the upper surface of the wafer, and the distance between point O and the upper surface of the wafer is 0, and the distance between point O1 and the upper surface of the wafer is kL1. When the range measurement ranges of the sensors do not overlap, the detection starting point of the second sensor is O1. At this time, the reference plane of the second sensor is the horizontal line passing through point O1, and the distance between the detection end point O2 of the second sensor and the upper surface of the wafer is kL1+kL2. When the range measurement ranges of the sensors do not overlap, the detection starting point of the third sensor is O2. At this time, the reference plane of the third sensor is the horizontal line passing through O2, and the distance between the detection end point O3 of the third sensor and the upper surface of the wafer is kL1+kL2+kL3. Similarly, the distance between the detection end point of the Nth sensor and the upper surface of the wafer is kL1+…+kL N , combined with the change curve 2 to determine kL1+…+kL N Whether the distance L between the upper and lower surfaces of the wafer is met S , such as kL1+…+kL N ≥L S , then the second number of sensors is determined to be N.

[0074] When the measuring range of each sensor is kL, the measuring range of each sensor is adjusted accordingly, which will not be described in detail here.

[0075] (3) In step S5, the final number of sensors to be set is determined based on the first number of sensors determined by the angle measurement range of the sensors and the second number of sensors determined by the range measurement range:

[0076] The angle measurement range of the multiple sensors is the x-axis, and the range measurement range of the multiple sensors is the y-axis. When the first number is equal to the second number, the number of sensors set is the first number or the second number, such as Figure 12 As shown, taking the number of sensors determined according to the sensor angle measurement range as 3 and the number of sensors determined according to the sensor range measurement range as 3 as an example, the measurement ranges of the first sensor, the second sensor and the third sensor are the corresponding shaded parts respectively.

[0077] When the first number is greater than the second number, the set number of sensors is the first number; when the first number is less than the second number, the set number of sensors is the second number. That is, the final set number of sensors is the larger of the first and second numbers. Figure 13 As shown, taking the first number of sensors determined according to the sensor angle measurement range as 4 and the second number of sensors determined according to the sensor range measurement range as 3 as an example, the measurement ranges of the first to third sensors are the corresponding shaded parts. In this case, the final number of sensors is determined to be 4. At this time, the range measurement ranges of the third sensor and the fourth sensor are adjusted by increasing the distance between the third sensor and the wafer surface respectively. As the distance between the sensor and the wafer surface increases, the effective range of the sensor decreases, and the range measurement range of the sensor is controlled in turn, as shown in FIG. Figure 14 As shown, part of the measuring range of the third sensor is divided into the fourth sensor, and the third sensor and the fourth sensor jointly detect the original measuring range of the third sensor according to a preset ratio. Preferably, the ratio is 1:1.

[0078] When the first number is 3 and the second number is 4, the final number of sensors is determined to be 4. By adjusting the angular postures of the third and fourth sensors, the angular measurement ranges of the third and fourth sensors are adjusted. Part of the angular measurement range of the third sensor is allocated to the fourth sensor, and the third and fourth sensors jointly detect the original angular measurement range of the third sensor in a preset ratio. Preferably, this ratio is 1:1. This fully utilizes the sensor's range and angular range, improving sensor utilization while ensuring measurement accuracy.

[0079] When the angle measurement range and range measurement range of the sensor overlap, the sensor's measurement range is as follows: Figure 15 As shown in the middle shaded area, the area surrounded by the same color corresponding to each sensor is the angle measurement range and range measurement range of the sensor.

[0080] The present invention has been described above by way of examples, but the present invention is not limited to the above specific embodiments. Any changes or modifications based on the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A sensor setting method for wafer detection, characterized in that: The following steps are involved: S1, obtain the angle range and measuring range of the sensor; S2, obtaining the wafer edge profile type; S3, dividing the angle measurement range of each sensor according to the wafer edge profile type and the angle range of the sensor, and determining the angle posture of each sensor; S4, dividing the measurement range of each sensor according to the wafer edge profile type and the sensor range; S5, determining the number of sensors according to the angle measurement range and the range measurement range of each sensor.

2. The sensor setting method for wafer detection according to claim 1, characterized in that: In step S1, the angle range of the sensor is α, the error coefficient is set to ρ, and the value range of ρ is (0, 1]. The range of the sensor is L, the error coefficient is set to k, and the value range of k is (0, 1).

3. The sensor setting method for wafer detection according to claim 1, characterized in that: In step S2, the wafer edge profile types include A-type profile, B-type profile, C-type profile and special-shaped profile.

4. The sensor setting method for wafer detection according to claim 1, wherein: The step S3 comprises the following steps: S3.1, obtaining a first curve of the change in angle between the tangent line corresponding to each point of the wafer edge contour and the wafer radial direction; S3.2, dividing the total measurement range of the variation curve 1 in sequence according to the angular range of the sensor to obtain the angular measurement range of each sensor; S3.3, determining the angular posture of each sensor and a first number of sensors according to the angular measurement range of each sensor.

5. The sensor setting method for wafer detection according to claim 4, characterized in that: In step S3.2, when dividing the angle measurement range of the sensor, the end point of the angle measurement range of the sensor coincides with the start point of the angle measurement range of the adjacent sensor.

6. The sensor setting method for wafer detection according to claim 4, characterized in that: In step S3.2, when dividing the angle measurement range of the sensor, an overlapping range is formed between the angle measurement range of the sensor and the angle measurement range of an adjacent sensor.

7. The sensor setting method for wafer detection according to claim 4, characterized in that: The step S4 comprises the following steps: S4.1, obtaining a second curve of the distance between each point on the wafer edge contour line and the wafer top surface; S4.2, setting an initial distance between the sensor and the wafer surface, and dividing the distance in sequence according to the sensor's measuring range and the total measuring range of the second variation curve to obtain the measuring range of each sensor; S4.

3. Determine a second number of sensors based on the measurement range of each sensor.

8. The sensor setting method for wafer detection according to claim 7, characterized in that: The step S5 comprises the following steps: S5.1, determining a set number of sensors based on the first number and the second number; S5.2, when the first number is equal to the second number, the set number of sensors is the first number or the second number; when the first number is greater than the second number, the set number of sensors is the first number; when the first number is less than the second number, the set number of sensors is the second number.

9. The sensor setting method for wafer detection according to claim 8, characterized in that: The step S5 further comprises the following steps: S5.

3. When the first number is greater than the second number, the distance between the end sensor and the adjacent sensor and the wafer surface is adjusted so that the end sensor and the adjacent sensor divide the original range measurement range of the adjacent sensor according to a preset ratio. When the first number is less than the second number, the angular posture of the end sensor and the adjacent sensor is adjusted so that the end sensor and the adjacent sensor divide the original angle measurement range of the adjacent sensor according to a preset ratio.

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