Wafer cutting method and system and wafer cutting equipment

Abstract

The invention discloses a wafer cutting method and system and wafer cutting equipment, and the wafer cutting method comprises the following steps: S1, obtaining a circle of distance measured by distance measuring sensors arranged at the periphery of a wafer bearing table, measuring the distance between each distance measuring sensor and a wafer ring frame by each distance measuring sensor, and concentrically arranging a wafer where the wafer ring frame is located on the wafer bearing table; s2, determining a difference value between a maximum value and a minimum value in a group of distances measured by the distance measuring sensor in a circle, and determining whether the difference value is greater than a difference value threshold value or not; s3, when it is determined that the difference value is larger than a difference value threshold value, machining is stopped, and an alarm is given; and S4, when it is determined that the difference value is smaller than or equal to a difference value threshold value, processing of the wafer is continued. According to the method, abnormal conditions can be found in time, machining is stopped, the possible problems caused by continuous wafer ring frame fixing and wafer cutting when the wafer ring frame is abnormal are effectively avoided, and the cutting quality is guaranteed.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor device processing, in particular to a wafer cutting method, system and wafer cutting equipment. Background Art

[0002] During wafer processing, the wafer body is concentrically attached to the wafer ring frame through a film as one wafer, and then the wafer is placed on the wafer stage of a dicing machine to cut the wafer body.

[0003] The patent document with the authorization announcement number CN218614808U discloses a commonly used workbench structure. In this structure, a set of fixing components are arranged on the periphery of the wafer stage (base) to fix the wafer ring frame.

[0004] However, in actual processing, there are abnormal conditions such as large deformation of the wafer ring frame itself, loose tilting of the support block of the fixing component, and uneven top surface height. These abnormal conditions will cause uneven force on different areas of the wafer ring frame when the wafer ring frame is fixed by the fixing component, causing the wafer ring frame to deform and pull the film. When the film is pulled, there are the following risks: (1) The overall position of the wafer moves slightly, causing the wafer to be unable to remain concentric with the wafer stage, affecting subsequent accurate cutting.

[0005] (2) The film becomes locally thinner due to pulling, causing different locations on the upper surface of the wafer to be uneven, resulting in deep and shallow cuts during cutting. Summary of the invention

[0006] The purpose of the present invention is to solve the above problems existing in the prior art and to provide a wafer cutting method, system and wafer cutting equipment.

[0007] The purpose of the present invention is achieved through the following technical solutions: The wafer cutting method comprises the following steps: S1, obtaining the distance measured by a circle of distance measuring sensors arranged on the periphery of the wafer stage, each distance measuring sensor measures the distance between itself and a wafer ring frame, and the wafer where the wafer ring frame is located is concentrically arranged on the wafer stage; S2, determining a difference between a maximum value and a minimum value in a set of distances measured by the distance measuring sensor in a circle, and determining whether the difference is greater than a difference threshold; S3, when it is determined that the difference is greater than the difference threshold, the processing is stopped and an alarm is issued; S4: When it is determined that the difference is less than or equal to the difference threshold, continue processing the wafer.

[0008] Preferably, a mounting ring is concentrically arranged on the outer periphery of the wafer support table, a circle of clamping mechanisms are evenly arranged on the mounting ring in a circle, the ranging sensor is arranged at or beside each clamping mechanism, and the clamping mechanism can be arranged on the mounting ring in a radially adjustable position along the wafer support table.

[0009] Preferably, the clamping mechanism includes a movable seat movably arranged on the mounting ring, the movable seat is provided with a pad and a pressing assembly for pressing the wafer ring frame onto the pad, the pressing assembly includes a pressing block and a clamping drive device for driving the pressing block to move axially and horizontally along the wafer table.

[0010] Preferably, the cushion block is connected to the movable seat by bolts whose axes are parallel to the axis of the wafer support platform, and a group of adjusting top screws are also passed through the cushion block, and the axes of the adjusting top screws are parallel to the axis of the wafer support platform.

[0011] Preferably, a group of clamping mechanisms are driven and adjusted synchronously by a synchronous driving mechanism; When the size information of the wafer to be processed is obtained, the synchronous driving mechanism is controlled to drive a group of the clamping mechanisms to adjust positions according to the size information of the wafer to be processed.

[0012] Preferably, the synchronous drive mechanism includes a drive ring concentrically arranged at the bottom of the mounting ring, the drive ring is connected to a rotation drive assembly that drives its rotation, and the drive ring is connected to a group of the clamping mechanisms through a group of linkage rods.

[0013] Preferably, a pressure sensor is provided on each of the pads. When it is determined that the difference is less than or equal to a difference threshold, the clamping mechanism is activated to fix the wafer ring frame, a group of pressure values ​​of the pressure sensor are obtained, and it is determined whether the minimum value in a group of pressure values ​​is greater than the pressure threshold. If so, the processing of the wafer continues; if not, the processing is stopped and an alarm is issued.

[0014] Preferably, during the cutting process, Acquire in real time a detection signal of a first detection component for detecting the working state of a first coupling in a lifting drive mechanism at a cutting mechanism, and determine whether the working state of the first coupling is normal; if it is determined that the working state of the first coupling is normal, continue processing the wafer; if it is determined that the working state of the first coupling is abnormal, stop processing; and / or obtaining in real time a detection signal of a second detection component for detecting the working state of a second coupling in a first direction translation mechanism at a cutting mechanism, and determining whether the working state of the second coupling is normal; if it is determined that the working state of the second coupling is normal, continuing the processing of the wafer; if it is determined that the working state of the second coupling is abnormal, stopping the processing; And / or obtain in real time a detection signal of a third detection component for detecting the working state of a third coupling in a second-direction translation mechanism connected to the wafer stage, and determine whether the working state of the third coupling is normal; if it is determined that the working state of the third coupling is normal, continue processing the wafer; if it is determined that the working state of the third coupling is abnormal, stop processing.

[0015] Wafer dicing system, including: A data acquisition unit is used to obtain the distance measured by a circle of distance measuring sensors arranged on the periphery of the wafer stage, each distance measuring sensor measures the distance between itself and a wafer ring frame, and the wafer on which the wafer ring frame is located is concentrically arranged on the wafer stage; a difference determination and comparison unit, used to determine the difference between the maximum value and the minimum value in a set of distances measured by the distance measuring sensor in a circle, and determine whether the difference is greater than a difference threshold; An alarm unit, used to stop processing and issue an alarm when it is determined that the difference is greater than a difference threshold; A processing unit is used to continue processing the wafer when it is determined that the difference is less than or equal to a difference threshold.

[0016] A wafer cutting device comprises a processor and a memory, wherein the memory stores a program executable by the processor, and when the program is executed, any of the wafer cutting methods described above is implemented.

[0017] The advantages of the technical solution of the present invention are mainly reflected in: The method of the present invention uses a group of distance measuring sensors to detect the distances from each of the sensors to different positions of the wafer ring frame before the wafer ring frame is fixed to determine whether there is any abnormality in the wafer ring frame when the wafer is concentrically placed on the wafer stage. The abnormality can be discovered in time and the processing can be stopped, which effectively avoids the problems that may be caused by continuing to fix the wafer ring frame and cut the wafer when the wafer ring frame is abnormal, and is beneficial to ensuring the cutting quality and cutting safety.

[0018] The clamping mechanism of the present invention changes the conventional method of using a flip cylinder in the prior art. The up and down movement method can effectively avoid the problem that the flip cylinder is not flipped into place, which may cause insufficient contact between the pressure plate and the surface of the wafer ring frame and failure to clamp. This is beneficial to ensure that the bottom surface of the pressure block is in full contact with the wafer ring frame.

[0019] The multiple clamping mechanisms of the present invention are driven and adjusted synchronously by a synchronous driving mechanism, which can effectively meet the needs of fixing wafer ring frames on wafers of different sizes, can be automatically adjusted, and reduce manual intervention; and only one power source is set, so the equipment cost and the use cost are lower; at the same time, the consistency of the adjustment of several clamping mechanisms can be effectively guaranteed.

[0020] The present invention arranges a pressure sensor at each pad block, which can effectively detect whether each clamping mechanism has fully clamped the wafer ring frame, and can timely discover the situation of not clamping, which is conducive to ensuring the reliability of clamping.

[0021] During the processing, the present invention detects the working status of the couplings of each moving mechanism in real time, can promptly discover the abnormal status of the coupling and stop processing, can avoid processing when the moving positions of the wafer table and the main shaft are inaccurate, and is beneficial to ensuring the processing quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a three-dimensional diagram of the wafer holding platform and its surrounding structures of the present invention; Figure 2 is a flow chart of a wafer cutting method according to Embodiment 1 of the present invention; Figure 3 It is a partial schematic diagram of the distance measuring sensor and the clamping mechanism arranged on the mounting ring of the present invention, in which the clamping block is hidden; Figure 4 is a stereogram of a mounting ring of the present invention; Figure 5 It is a schematic diagram of the clamping mechanism of the present invention being connected to the driving ring via a linkage rod; Figure 6 is a perspective view of a drive ring of the present invention; Figure 7 is a flow chart of the wafer cutting method in Embodiment 2 of the present invention; Figure 8 It is a three-dimensional diagram of the wafer holding platform and its surrounding structures of the present invention, in which the pressing blocks of each pressing mechanism are hidden; Fig. 9 is a flow chart of a wafer cutting method according to Embodiment 3 of the present invention; Fig.10 It is an exploded view of the wafer cutting mechanism of the present invention, in which the wafer stage and its surrounding structures are hidden; Fig.11 It is a first perspective stereogram of the third detection assembly and the third coupling area in the present invention; Fig.12 It is a second perspective stereogram of the third detection component and the third coupling area in the present invention. DETAILED DESCRIPTION

[0023] The purpose, advantages and features of the present invention will be illustrated and explained by the non-limiting description of the following preferred embodiments. These embodiments are only typical examples of the application of the technical solution of the present invention, and any technical solution formed by equivalent replacement or equivalent transformation falls within the scope of protection claimed by the present invention.

[0024] In the description of the scheme, it should be noted that the terms "center", "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience and simplification of description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance. Example 1

[0025] The wafer cutting method disclosed in the present invention is described below in conjunction with the accompanying drawings. The wafer cutting method is based on a wafer cutting device. Like the prior art, the wafer cutting device generally includes a wafer stage 100 for carrying and fixing the wafer.

[0026] Different from the prior art: As attached Figure 1 As shown, in the present invention, a mounting ring 200 concentric with the wafer stage 100 is arranged on the outer periphery of the wafer stage 100, and the top surface of the mounting ring 200 is lower than the top surface of the wafer stage 100. A group of clamping mechanisms 300 are evenly distributed circumferentially on the mounting ring 200. The clamping mechanisms 300 are used to fix the wafer ring frame A on the wafer placed on the wafer stage 100. The number of the clamping mechanisms 300 can be designed as needed, preferably 3-6. In this embodiment, 4 clamping mechanisms 300 are taken as an example for description.

[0027] Each of the pressing mechanisms 300 includes a pad 310 and a pressing assembly 320 for pressing the wafer ring frame A of the wafer on the wafer stage 100 onto the pad 310. The pad 310 is located above the mounting ring, and the top surface of the pad 310 is slightly lower than the top surface of the wafer stage 100, so that when the wafer ring frame A is pressed onto the pad 310, the film on the wafer can be fully sealed with the edge of the wafer stage 100 to ensure that the wafer stage 100 reliably adsorbs the film.

[0028] The pressing assembly 320 includes a pressing block 321 and a pressing drive device 322 that drives the pressing block 321 to move along the axis of the wafer stage 100 and to move horizontally. The pressing drive device 322 passes through the mounting ring 200 and is preferably a rotary clamping cylinder. The cylinder shaft of the rotary clamping cylinder can rotate 90° and stretch up and down. When the wafer ring frame A does not need to be fixed, the cylinder shaft of the rotary clamping cylinder extends upward and the pressing block 321 is located outside the wafer ring frame A, which can avoid interfering with the loading and unloading of the wafer; when the wafer ring frame A needs to be fixed, the cylinder shaft of the rotary clamping cylinder retracts downward and rotates 90° so that the pressing block 321 is pressed on the top surface of the wafer ring frame A so that the wafer ring frame A is pressed against the cushion block 310. Of course, the pressing drive device 322 can also adopt other feasible structures, such as a structure in which a rotary cylinder and a cylinder cooperate.

[0029] As attached Figure 1 As shown, a circle of distance measuring sensors 400 are also arranged on the mounting ring 200. The distance measuring sensors 400 detect the distance upward. At least one distance measuring sensor 400 can be arranged beside each clamping mechanism 300. Of course, one distance measuring sensor 400 can also be arranged on each cushion block 310. The distance measuring sensor 400 is, for example, a laser distance measuring sensor, which is not limited here. When the wafer is placed concentrically on the wafer stage 100, the wafer ring frame A of the wafer is located above a circle of distance measuring sensors 400, so that each distance measuring sensor 400 can measure the distance between itself and the wafer ring frame A.

[0030] Correspondingly, as attached Figure 2 As shown, the wafer cutting method comprises the following steps: S0, manually place the wafer to be processed on the wafer stage 100 or place the wafer to be processed on the wafer stage 100 through known automated equipment. After that, the wafer can be adjusted to a position concentric with the wafer stage 100 through a centering mechanism. The centering mechanism and its specific adjustment process are known technologies and will not be described in detail here.

[0031] S1, obtaining the distance between the wafer stage and the wafer ring frame A measured by a circle of the distance measuring sensors 400 arranged on the periphery of the wafer stage; S2, determining the difference between the maximum value and the minimum value in a set of distances measured by the distance measuring sensor 400 in one circle, and determining whether the difference is greater than a difference threshold, wherein the difference threshold is preferably 3 microns; S3. When it is determined that the difference is greater than the difference threshold, this indicates that there is a height difference at different positions of the wafer ring frame A, and the height difference exceeds the acceptable range. If the wafer ring frame A continues to be fixed by the clamping mechanism 300, there will be a problem of excessive stretching of the film. Therefore, the processing should be stopped and an alarm should be issued to remind the staff to handle it.

[0032] S4. When it is determined that the difference is less than or equal to the difference threshold, this indicates that the heights of different positions of the wafer ring frame A are the same or approximately the same. When the clamping mechanism 300 fixes the wafer ring frame A, the influence of the deformation of the film can be ignored. Therefore, the processing of the wafer can continue, that is, the wafer ring frame A can be fixed by the clamping mechanism 300 and subsequent cutting can be performed.

[0033] In S3, common reasons why the difference exceeds the difference threshold are as follows: one reason is that the top surface heights of several pads 310 are not uniform; another reason is that the wafer ring frame A itself has obvious deformation.

[0034] When it is determined that the top surface height of the cushion block 310 is not uniform, the cushion block 310 needs to be adjusted. Specifically, as shown in the attached Figure 3 As shown, the pad 310 is connected to the mounting ring 200 by means of a bolt (not shown in the figure) passed through a connection hole 311 of the pad, the axis of the bolt is parallel to the axis of the wafer support table 100, and at the same time, a group of adjusting top screws 340 are passed through the pad 310, the axis of the adjusting top screws 340 is parallel to the axis of the wafer support table 100, when it is necessary to adjust the top surface height of a pad 310, it can be achieved by adjusting the connection depth between the bolt and the mounting ring 200 and the distance that the adjusting top screws 340 extend below the pad 310.

[0035] When it is determined that the wafer ring frame A itself has obvious deformation, the wafer body can be removed from the film and re-filmed before cutting. At the same time, the abnormal wafer ring frame A can be corrected by correction equipment, such as punching the deformed wafer frame by stamping equipment. Example 2

[0036] In the above-mentioned embodiment 1, the position of each clamping mechanism 300 is fixed. In actual processing, the sizes of wafers are various. Therefore, in order to better adapt to the processing of wafers of different sizes, each of the clamping mechanisms 300 can be set on the mounting ring 200 along the radial adjustment position of the wafer stage 100. At the same time, at least two ranging sensors 400 are set next to each of the clamping mechanisms 300. The ranging sensors 400 are arranged along the moving direction of the clamping mechanism 300 next to it. Of course, if the ranging sensor 400 is set on the pad, only one ranging sensor 400 needs to be set at each clamping mechanism.

[0037] Specifically, as attached Figure 4 , Attachment Figure 5 As shown, the mounting ring 200 is a circular ring, and four notches 210 are evenly spaced on the outer edge of the circular ring. A clamping mechanism 300 is movably disposed at each notch 210. At this time, the clamping mechanism 300 includes a moving seat 330 slidably disposed at the notch 210, and the pressing assembly 320 and the cushion block 310 are disposed on the moving seat 330. In addition, the moving seat 330 of each clamping mechanism 300 can be connected to a driver that drives it to move along the notch 210. The driver is, for example, a known linear module, a rodless cylinder, etc., which is not limited here.

[0038] Further, in order to reduce the driving source, in a more preferred embodiment, as shown in the attached Figure 5 As shown, a group of clamping mechanisms 300 are driven and adjusted synchronously by a synchronous driving mechanism 500; the synchronous driving mechanism 500 includes a driving ring 510 concentrically arranged at the bottom of the mounting ring 200, the driving ring 510 is connected to a self-rotation driving assembly 520 that drives its self-rotation, and the driving ring 510 is connected to a group of clamping mechanisms 300 through a group of linkage rods 530. The self-rotation driving assembly 520 is, for example, arranged on the hollow turntable; or the self-rotation driving assembly 520 includes a roller, the roller is connected to a rotary driving motor that drives its self-rotation and the wheel surface of the roller is in contact with the outer peripheral surface of the driving ring 510, so that when the roller rotates, the roller drives the driving ring 510 to rotate to achieve adjustment; of course, the roller can also be a gear, and the outer periphery of the driving ring is formed with teeth that mesh with the gear.

[0039] As attached Figure 5 As shown, a group of connecting plates 511 are provided on the outer edge of the driving ring 510, each of the connecting plates 511 is pivotally connected to one end of an L-shaped linkage rod 530, and the other end of the linkage rod 530 is pivotally connected to the movable seat 330 of the clamping mechanism 300, so that when the driving ring 510 rotates, several clamping mechanisms 300 can be driven to adjust synchronously through a group of linkage rods 530.

[0040] In order to ensure the position accuracy of the driving ring 510 when rotating, a group of positioning pins 220 are provided on one of the driving ring 510 and the mounting ring 200, and an arc groove or arc hole 512 corresponding to each positioning pin 220 is provided on the other.

[0041] As attached Figure 4 -Attached Figure 6As shown, three locating pins 220 are evenly distributed on the circumference at the bottom of the mounting ring 200, and the circle where the three locating pins 220 are located is concentric with the mounting ring 200. At the same time, three arc holes 512 are concentrically arranged on the driving ring 510, and each of the locating pins 220 is embedded in an arc hole 512, so that when the driving ring 510 rotates, the three locating pins 220 can move along the arc holes 512 where they are located, and realize the limiting of the driving ring 510 to ensure the synchronization of multiple linkage rods 530.

[0042] When processing a wafer of a certain size, the size information of the wafer can be manually input first. Of course, the size information of the wafer to be processed can also be automatically acquired through other methods. For example, the size information of the wafer can be determined by detecting the size of the material box used to hold the wafer, or the size of the wafer can be determined through image recognition after loading. This is not limited here.

[0043] As attached Figure 7 As shown, when the size information of the wafer to be processed is obtained, the synchronous driving mechanism 500 is controlled to drive a group of the clamping mechanisms 300 to adjust the position according to the size information of the wafer to be processed. For example, the current position of the clamping mechanism can fix the wafer ring frame of an 8-inch wafer. When a 12-inch wafer needs to be processed, several clamping mechanisms 300 can be adjusted toward the outer edge of the mounting ring 200. Example 3

[0044] When the pressing mechanism 300 is pressed, there is a problem that the wafer ring frame A cannot be stably fixed due to unstable gas source, slight deformation of the wafer ring frame A, deformation of the pressing block 321, etc. Therefore, as shown in the attached Figure 8 As shown, a pressure sensor 350 is provided on each cushion block 310 , and the pressure sensor 350 is located in the middle of the cushion block 310 , and a detection point of the pressure sensor 350 slightly protrudes above the top surface of the cushion block 310 .

[0045] As attached Fig. 9 As shown, when it is determined that the difference does not exceed the difference threshold and the clamping mechanism can be started, the clamping mechanism 300 is started to fix the wafer ring frame A of the wafer. At this time, a group of pressure values ​​of the pressure sensor 350 is obtained, and it is determined whether the minimum value in a group of pressure values ​​is greater than the pressure threshold. If so, the processing of the wafer continues, and the cutting of the wafer on the wafer stage can be started. If not, the processing is stopped and an alarm is issued. At this time, manual inspection and processing are performed. For example, the position of the magnetic switch of the rotary clamping cylinder can be adjusted so that the pressing block 321 of the pressing assembly 320 can be pressed tighter. The specific processing measures can be selected according to needs and are not limited here. Example 4

[0046] In the wafer cutting equipment, as shown in the attached Fig.10 As shown, the wafer table 100 is arranged on a second direction translation mechanism 600 that drives it to translate in the second direction. At the same time, the main shaft 710 of the cutting mechanism 700 is arranged on a lifting drive mechanism 720 that drives it to move up and down and a first direction translation mechanism 730 that drives the lifting drive mechanism 720 to translate in the first direction, and the first direction is perpendicular to the second direction. During processing, it is necessary to drive the wafer table 100 to move by the second direction translation mechanism 600 and drive the main shaft 710 to move by the lifting drive mechanism 720 and the first direction translation mechanism 730 to achieve cutting.

[0047] The first direction translation mechanism 730, the lifting drive mechanism 720 and the second direction translation mechanism 600 all use a motor and a lead screw to produce linear motion, and the power output shaft of the motor is connected to the screw of the lead screw through a coupling. That is, the lifting drive mechanism 720 includes a first coupling, the first direction translation mechanism 730 includes a second coupling, and the second direction translation mechanism 600 includes a third coupling.

[0048] The connection stability between the coupling and the power output shaft and the screw of the lead screw will have a significant impact on the position accuracy of the wafer table 100 and the position accuracy of the main shaft 710, which will greatly affect the cutting accuracy. Therefore, it is necessary to detect the working state of each coupling, and correspondingly, a first detection component is set to detect the working state of the first coupling, a second detection component is set to detect the working state of the second coupling, and a third detection component is set to detect the working state of the third coupling.

[0049] The first detection component, the second detection component and the third detection component have the same principle for detecting the working status of the first coupling, the second coupling and the third coupling. The following is an example of detecting the working status of the third coupling 610 by the third detection component.

[0050] As attached Fig.11 , Attachment Fig.12As shown, the third detection assembly at least includes a first detector arranged on the motor seat 620 where the motor is located. There are two first detectors and they correspond to the position of a hub 611 of the third coupling respectively. The first detector can be a known cross-beam sensor, which includes a transmitter 630 and a receiver 640 arranged on two support plates of the motor seat 620. The detection light emitted by the transmitter 630 is close to or tangent to the edge of the outer peripheral surface of the hub 611 in the locked state. At this time, the detection light emitted by the transmitter 630 can be received by the receiver 640. When the fastening screws of the locking hub 611 are loosened, the outer peripheral surface of the hub 611 will expand outward due to the loosening, thereby blocking the detection light emitted by the transmitter 630. At this time, the receiver 640 cannot receive the detection light, so it can be determined that the fastening screws are loose, that is, it can be determined that the working state of the third coupling is abnormal. Of course, in other embodiments, the first detector can also be a structure in which a proximity sensor or a self-reflection sensor cooperates with a reflector, which is not limited here.

[0051] As attached Fig.11 As shown, the third detection assembly may also include a second detector disposed on the motor seat 620, and the second detection sensor is used to detect the hub 611 of the third coupling away from the motor. The second detector is, for example, a visual recognition device, and the visual recognition device, for example, uses a CCD (charge coupled device) for image acquisition. The motor seat 620 is also provided with a light source 660 located on the same side as the CCD 650, and the support plate is provided with perforations corresponding to the light source and the CCD. In addition, feature points are set on the outer peripheral surface of the hub 611, and the feature points are, for example, a groove or a convex point or a specific pattern, etc., which are not limited here.

[0052] When the motor is in the initial position, the characteristic points on the hub 611 are facing the CCD, and the image of the hub 611 at this time is collected as the standard image. Subsequently, after the motor is started, when it is determined that the power output shaft rotates one circle, the CCD is controlled to collect an image, and the collected image is compared with the standard image to determine whether the positions of the characteristic points on the collected image are consistent with the characteristic points on the standard image or whether the position difference meets the requirements. If they are inconsistent or the position difference does not meet the requirements, that is, the synchronization between the third coupling and the power output shaft does not meet the requirements, then it can be determined that the working state of the third coupling is abnormal; otherwise, it can be determined that the working state of the third coupling is normal.

[0053] Of course, in other embodiments, the second detector may also adopt a proximity sensor or a ranging sensor 400. For example, when a proximity sensor is adopted, a characteristic point is provided on the wheel hub 611. The characteristic point is, for example, a convex point protruding from the outer peripheral surface of the wheel hub 611. When the convex point is directly opposite to the proximity sensor, the proximity sensor can detect the convex point. When other positions of the outer peripheral surface of the wheel hub 611 are directly opposite to the proximity sensor, the proximity sensor cannot detect the outer peripheral surface of the wheel hub 611.

[0054] When the motor is in the initial position, the proximity sensor can detect the convex point. Subsequently, each time the power output shaft rotates one circle, it can be determined whether the proximity sensor detects the convex point again or whether the difference between the duration of the power output shaft rotating one circle and the duration of the coupling rotating one circle determined by the proximity sensor is within the threshold range. The time interval between the proximity sensor detecting the convex point twice in a row is the duration of the third coupling rotating one circle. If the power output shaft rotates one circle, the proximity sensor detects the convex point again or the difference between the duration of the power output shaft rotating one circle and the duration of the third coupling rotating one circle is within the difference threshold, it is determined that the synchronization of the third coupling and the power output shaft meets the requirements and the working state of the third coupling is normal; otherwise, it is determined that the working state of the third coupling is abnormal.

[0055] Therefore, during the wafer cutting process, the detection signal of the first detection component is obtained in real time, and it is determined whether the working state of the first coupling is normal; if it is determined that the working state of the first coupling is normal, the processing of the wafer continues; if it is determined that the working state of the first coupling is abnormal, the processing is stopped.

[0056] And / or obtain the detection signal of the second detection component in real time, and determine whether the working state of the second coupling is normal; if it is determined that the working state of the second coupling is normal, continue to process the wafer; if it is determined that the working state of the second coupling is abnormal, stop processing.

[0057] And / or obtain the detection signal of the third detection component in real time, and determine whether the working state of the third coupling is normal; if it is determined that the working state of the third coupling is normal, continue to process the wafer; if it is determined that the working state of the third coupling is abnormal, stop processing. Example 5

[0058] This embodiment discloses a wafer cutting system, comprising: A data acquisition unit, used to obtain the distance measured by a circle of distance measuring sensors 400 arranged on the periphery of the wafer stage 100, each distance measuring sensor measures the distance between itself and a wafer ring frame, and the wafer where the wafer ring frame is located is concentrically arranged on the wafer stage; A difference determination and comparison unit, used to determine the difference between the maximum value and the minimum value in a set of distances measured by the distance measuring sensor 400 in a circle, and determine whether the difference is greater than a difference threshold; An alarm unit, used to stop processing and issue an alarm when it is determined that the difference is greater than a difference threshold; A processing unit is used to continue processing the wafer when it is determined that the difference is less than or equal to a difference threshold. Example 6

[0059] This embodiment discloses a wafer cutting device, including a processor and a memory, wherein the memory stores a program executable by the processor, and when the program is executed, the wafer cutting method described above is implemented.

[0060] There are many implementation methods of the present invention, and all technical solutions formed by equivalent transformation or equivalent transformation fall within the protection scope of the present invention.

Claims

1. A wafer cutting method, characterized in that: The steps include: S1, obtaining the distance measured by a circle of distance measuring sensors arranged on the periphery of the wafer stage, each distance measuring sensor measures the distance between itself and a wafer ring frame, and the wafer where the wafer ring frame is located is concentrically arranged on the wafer stage; S2, determining a difference between a maximum value and a minimum value in a set of distances measured by the distance measuring sensor in a circle, and determining whether the difference is greater than a difference threshold; S3, when it is determined that the difference is greater than the difference threshold, the processing is stopped and an alarm is issued; S4: When it is determined that the difference is less than or equal to the difference threshold, continue processing the wafer.

2. The wafer cutting method according to claim 1, characterized in that: A mounting ring is concentrically arranged on the outer circumference of the wafer support table, a circle of clamping mechanisms are evenly arranged on the mounting ring, and the distance measuring sensor is arranged at or beside each clamping mechanism. The clamping mechanism can be arranged on the mounting ring in a radially adjustable position along the wafer support table.

3. The wafer cutting method according to claim 2, characterized in that: The clamping mechanism includes a movable seat movably arranged on the mounting ring, the movable seat is provided with a pad and a pressing assembly for pressing the wafer ring frame onto the pad, the pressing assembly includes a pressing block and a clamping drive device for driving the pressing block to move axially and horizontally along the wafer stage.

4. The wafer cutting method according to claim 3, characterized in that: The cushion block is connected to the movable seat by bolts whose axes are parallel to the axes of the wafer support platform. A group of adjusting top screws are also passed through the cushion block, and the axes of the adjusting top screws are parallel to the axes of the wafer support platform.

5. The wafer cutting method according to claim 2, characterized in that: A set of clamping mechanisms is driven and adjusted synchronously by a synchronous driving mechanism; When the size information of the wafer to be processed is obtained, the synchronous driving mechanism is controlled to drive a group of the clamping mechanisms to adjust positions according to the size information of the wafer to be processed.

6. The wafer cutting method according to claim 5, characterized in that: The synchronous drive mechanism comprises a drive ring concentrically arranged at the bottom of the mounting ring, the drive ring is connected to a rotation drive assembly that drives its rotation, and the drive ring is connected to a group of the clamping mechanisms through a group of linkage rods.

7. The wafer cutting method according to claim 3, characterized in that: A pressure sensor is provided on each of the pads. When it is determined that the difference is less than or equal to the difference threshold, the clamping mechanism is started to fix the wafer ring frame, a group of pressure values ​​of the pressure sensor are obtained, and it is determined whether the minimum value in a group of pressure values ​​is greater than the pressure threshold. If so, the processing of the wafer continues; if not, the processing is stopped and an alarm is issued.

8. The wafer cutting method according to any one of claims 1 to 7, characterized in that: During the cutting process, Acquire in real time a detection signal of a first detection component for detecting the working state of a first coupling in a lifting drive mechanism at a cutting mechanism, and determine whether the working state of the first coupling is normal; if it is determined that the working state of the first coupling is normal, continue processing the wafer; if it is determined that the working state of the first coupling is abnormal, stop processing; and / or obtaining in real time a detection signal of a second detection component for detecting the working state of a second coupling in a first direction translation mechanism at a cutting mechanism, and determining whether the working state of the second coupling is normal; if it is determined that the working state of the second coupling is normal, continuing the processing of the wafer; if it is determined that the working state of the second coupling is abnormal, stopping the processing; And / or obtain in real time a detection signal of a third detection component for detecting the working state of a third coupling in a second-direction translation mechanism connected to the wafer stage, and determine whether the working state of the third coupling is normal; if it is determined that the working state of the third coupling is normal, continue processing the wafer; if it is determined that the working state of the third coupling is abnormal, stop processing.

9. A wafer cutting system, characterized in that: include: A data acquisition unit is used to obtain the distance measured by a circle of distance measuring sensors arranged on the periphery of the wafer stage, each distance measuring sensor measures the distance between itself and a wafer ring frame, and the wafer on which the wafer ring frame is located is concentrically arranged on the wafer stage; a difference determination and comparison unit, used to determine the difference between the maximum value and the minimum value in a set of distances measured by the distance measuring sensor in a circle, and determine whether the difference is greater than a difference threshold; An alarm unit, used to stop processing and issue an alarm when it is determined that the difference is greater than a difference threshold; A processing unit is used to continue processing the wafer when it is determined that the difference is less than or equal to a difference threshold.

10. A wafer cutting device, comprising a processor and a memory, wherein the memory stores a program executable by the processor, wherein: When the program is executed, the wafer cutting method as described in any one of claims 1 to 8 is implemented.

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