Deposition system and wafer placement detection method
By designing a combination of multiple support members and detection devices in the semiconductor deposition system, the problem of abnormal wafer placement is solved, stable support and safe grasp of wafers are achieved, and the reliability and production capacity of equipment are improved.
Patent Information
- Application Number
- CN202411960103.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-27
- Publication Date
- 2025-04-18
AI Technical Summary
In semiconductor deposition systems, breakage or tilt of the lifting device leads to abnormal wafer placement, which in turn can lead to wafer fragmentation and chamber contamination.
A deposition system including a device body, a stage, a support and a detection device is designed. The wafer is supported to the grab position by at least three movable support members, and the detection device is used to monitor whether there is a occlusion on the optical path to determine whether the wafer is placed abnormally.
By stably supporting the wafer and real-time monitoring of its placement status, the wafer is avoided tilt and fragmentation, ensuring the safe placement and grabbing of the wafer, and improving the production capacity and reliability of the equipment.
Smart Images
Figure CN119843251A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of semiconductor technology, and in particular to a deposition system and a wafer placement detection method. Background Art
[0002] In semiconductor deposition systems, the lifting device can assist the rise and fall of the wafer, making it easier for the robot to grab and place the wafer. In related technologies, the lifting device may break, causing the wafer to tilt and be placed abnormally. In this case, if the wafer is continued to be grabbed, it will cause the wafer to break and the chamber to be contaminated. Summary of the invention
[0003] The embodiments of the present application provide a deposition system and a wafer placement detection method, which can detect whether the wafer is placed abnormally to avoid damaging the wafer.
[0004] A first aspect. An embodiment of the present application provides a deposition system. The deposition system includes an equipment body, a carrier, a support member, and a detection device. A process chamber is formed in the equipment body. The carrier is disposed in the process chamber. At least three supports are movably disposed on the carrier, and at least three supports are used to support the wafer to a grasping position. The detection device is used to detect whether there is an obstruction on the optical path, and the optical path of the detection device is lower or higher than the wafer at the grasping position.
[0005] Optionally, the height difference between the optical path of the detection device and the wafer at the gripping position is less than 1 mm.
[0006] Optionally, the detection device and the device body are separate devices.
[0007] Optionally, the deposition system further includes a gripping device, which is used to transfer the wafer in the process chamber, and the detection device is installed on the gripping device.
[0008] Optionally, when the wafer is in the grasping position, the detection device can switch between the first position and the second position by lifting; the first position is higher than the second position; when the detection device is in the first position, the upper surface of the support is lower than the optical path of the detection device, and the wafer blocks the light path; when the detection device is in the second position, the upper surface of the support is higher than the optical path of the detection device.
[0009] Optionally, the height difference between the detection device at the first position and the support member at the second position is less than 1 mm.
[0010] Optionally, the detection device includes a transmitter and a receiver, the receiver is used to receive the light emitted by the transmitter and reflected; the transmitter and the receiver are arranged in opposite directions, or the transmitter and the receiver are facing the same direction.
[0011] Optionally, a film transfer port is provided on one side of the process chamber for allowing the grabbing device to extend into the process chamber.
[0012] In a second aspect, an embodiment of the present application provides a wafer placement detection method. The method comprises:
[0013] Verification, including:
[0014] The stage is moved to the wafer transfer position, and the support member is extended so that the wafer can be placed at the gripping position, and the test wafer with the correct position is placed at the gripping position;
[0015] Move the detection device to a first position so that the optical path of the detection device is higher than the upper surface of the support member and lower than the upper surface of the test wafer, and obtain a first detection result;
[0016] Move the detection device to a second position so that the optical path of the detection device is lower than the upper surface of the support member, and obtain a second detection result;
[0017] If the first detection result is occlusion and the second detection result is no occlusion, the verification is successful; in other cases, the verification fails;
[0018] In case of verification failure, output the information of troubleshooting and restart the above verification steps;
[0019] If the verification is successful, proceed to the normal detection steps.
[0020] Optionally, routine detection steps include
[0021] When the wafer position needs to be detected, the detection device is set at the second position to obtain a third detection result;
[0022] determining a third test result;
[0023] When the third detection result is occlusion, outputting a result of wafer placement abnormality;
[0024] When the third detection result is that there is no obstruction, a result indicating that the wafer is placed normally is output.
[0025] The beneficial effects of the present application are as follows: Different from the prior art, by providing at least three support members, the wafer can be stably supported. The wafer can be switched between the process position and the gripping position by the cooperation of the support member and the stage, thereby realizing the placement and gripping of the wafer. Further, by providing a detection device, it is possible to monitor whether there is an obstruction on the optical path, thereby determining whether the wafer is tilted, so as to achieve the purpose of detecting whether the wafer is placed abnormally and avoiding damage to the wafer. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1It is a structural schematic diagram of the deposition system of the present application in which the wafer is normally placed and the support member is in the first position;
[0027] Figure 2 is a schematic diagram of the structure of the support member in the deposition system of the present application in the process position;
[0028] Figure 3 It is a schematic diagram of abnormal wafer placement of the deposition system of the present application;
[0029] Figure 4 is a schematic structural diagram of the support member of the deposition system of the present application in the second position;
[0030] Figure 5 It is a flow chart of the wafer placement detection method of the present application.
[0031] Reference numerals:
[0032] Deposition system, 1; equipment body, 11; process chamber, 111; stage, 12; support, 13; gripping device, 15; detection device, 14;
[0033] Wafer, 20. DETAILED DESCRIPTION
[0034] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0035] In existing semiconductor thin film deposition equipment, the wafer lifting device is one of the indispensable devices. In the process of placing the wafer, performing the process and removing the wafer, the lifting device may sometimes break due to some unexpected reasons, which in turn causes the wafer to tilt or break, affecting the production capacity of the equipment. In related equipment, because the breakage or tilt of the lifting device cannot be detected, when taking out the wafer, if the wafer is tilted, the robot will still directly grab the wafer, causing the wafer to break and causing contamination of the chamber. In order to improve the above technical problems, the present application may provide the following embodiments.
[0036] Combination Figures 1 to 4, an embodiment of the present application provides a deposition system 1. The deposition system 1 includes an equipment body 11, a carrier 12, a support 13 and a detection device 14. A process chamber 111 is formed in the equipment body 11. The carrier 12 is arranged in the process chamber 111. The carrier 12 can be a heater. The wafer 20 can be placed on the carrier 12. Process gas can be introduced into the process chamber 111, a radio frequency field can be fed into the process chamber 111, and the wafer 20 can be heated to the process temperature under the action of the heating element. A film transfer port is provided on one side of the process chamber 111, and the wafer 20 can enter the process chamber 111 through the film transfer port.
[0037] At least three support members 13 are movably disposed on the carrier 12, and at least three support members 13 are used to support the wafer 20 to the grasping position (combined with Figure 1 As shown in FIG. 1 ). When the stage 12 is lowered, the support member 13 can be raised relative to the stage 12 and extended, so as to be used to receive the wafer 20 introduced into the process chamber 111. When the stage 12 is raised, the support member 13 is lowered relative to the stage 12, and the wafer 20 falls on the stage 12 and is placed in the process position (combined with FIG. 1 ). Figure 2 As shown) for coating.
[0038] The support member 13 has a support position (combined Figure 1 shown) and process location (combined Figure 2 When the support member 13 is in the supporting position, it can be used to receive the wafer 20 when there is no wafer 20 placed, and it can facilitate the removal of the wafer 20 when there is a wafer 20 placed. When the support member 13 is in the process position, the wafer 20 is placed on the carrier 12, and is in the process position, and can be coated. Among them, the grasping position means that when the support member 13 is in the supporting position, the wafer 20 can be supported in a position for grasping.
[0039] The deposition system 1 further includes a detection device 14. The detection device 14 may be a photoelectric sensor. The detection device 14 is used to detect whether there is an obstruction on the optical path. The optical path of the detection device 14 is lower than or higher than the wafer 20 at the gripping position. The following is an exemplary description of the case where the optical path is lower than the wafer 20 at the gripping position (for example Figure 1 When the support 13 is not damaged and the wafer 20 is placed normally, the wafer 20 will not tilt or the tilt angle is not enough to block the optical path of the detection device 14. When the support 13 is broken or the placement is offset, the wafer 20 is placed abnormally (combined with Figure 3 Schematic diagram), the wafer 20 will be tilted, blocking the light path of the detection device 14. By setting the light path of the detection device 14 lower than the wafer 20 at the grasping position, the light path can be prevented from being blocked when the wafer 20 is placed normally. However, when the wafer 20 is tilted, the light path of the detection device 14 is blocked.
[0040] In some embodiments, the detection device 14 includes a transmitter (not shown) and a receiver (not shown), and the receiver is used to receive the light reflected after being emitted by the transmitter. The transmitter and the receiver are arranged in opposite directions, or the transmitter and the receiver are facing the same direction. The transmitter emits light, and the receiver can receive the light. Through the emission and reception of light, it is possible to detect whether there is an object blocking the light path.
[0041] When the transmitter and the receiver are arranged in opposite directions, the transmitter and the receiver can be placed on both sides of the wafer 20, respectively. When the optical path is not blocked, the light emitted by the transmitter can be received by the receiver. When the optical path is blocked, the light emitted by the transmitter cannot be received by the receiver. In this way, when it is detected that the receiver cannot receive the light, it can be determined that the placement of the wafer 20 is abnormal, so that timely adjustments can be made.
[0042] When the transmitter and the receiver are facing the same direction, the light emitted by the transmitter can be received by the receiver after being reflected by the object on the optical path. In some embodiments, the light may be reflected by the side wall of the process chamber 111, or it may be reflected by the wafer 20. Since the travel time of the light reflected by the wafer 20 and the light reflected by the side wall of the process chamber 111 is different, it can be determined whether it is blocked by the wafer 20 according to the time it takes for the light to return. Optionally, the detection device 14 can be a distance measuring device, which can directly measure the distance between the detection device 14 and the obstruction on the optical path. Since the distance after the wafer 20 is blocked is different from the distance blocked by the side wall of the process chamber 111, it can also be determined by detecting the distance whether the wafer 20 is placed tilted. In other embodiments, the optical path of the detection device 14 will be blocked except when the wafer 20 is placed tilted. In other cases, the receiver cannot receive the returned light because there is no obstruction or the side wall of the process chamber 111 reflects the light to other directions. In this case, it can be determined that the placement of the wafer 20 is abnormal by detecting that the receiver receives the light.
[0043] Among them, the distance between the detection light path and the wafer 20 at the grasping position can affect the sensitivity of the detection device 14 in detecting the placement of the wafer 20. If the distance between the detection light path and the wafer 20 at the grasping position is 0, any slight tilt of the wafer 20 may trigger the detection device 14 and identify that the wafer 20 is tilted. If the distance between the detection light path and the wafer 20 at the grasping position is large, the wafer 20 needs to be tilted to a greater extent to trigger the detection device 14 and identify that the wafer 20 is tilted. The specific embodiment of the detection device 14 can be referred to the following exemplary description. Among them, the distance between the detection light path and the wafer 20 at the grasping position refers to the distance between the two in the height direction, that is, the distance in the up and down directions in the accompanying drawings. Optionally, the distance between the detection light path and the wafer 20 at the grasping position refers to the distance in a direction perpendicular to the detection light path.
[0044] In some embodiments, the distance between the optical path of the detection device 14 and the wafer 20 at the grasping position is less than 1 mm. The distance between the optical path of the detection device 14 and the preset grasping unknown can be 0.1 mm, 0.3 mm, 0.5 mm, 0.7 mm or 0.9 mm. If the distance between the optical path of the detection device 14 and the wafer 20 at the grasping position is too large, the detection device 14 can only be triggered when the wafer 20 is tilted at a large angle, which will cause the detection device 14 to be unable to recognize a slight tilt of the wafer 20, resulting in the wafer 20 still being grasped in a tilted state, which can easily cause the wafer 20 to break.
[0045] In other embodiments, the distance between the optical path of the detection device 14 and the wafer 20 at the gripping position is greater than 0.1 mm. If the distance between the optical path of the detection device 14 and the wafer 20 at the gripping position is too small, any slight tilt of the wafer 20 may cause the detection device 14 to be triggered. However, due to certain tolerances of parts such as the wafer 20 and the support 13 during the manufacturing process, the wafer 20 can be allowed to tilt at a smaller angle within a limited range. By setting the distance between the optical path of the detection device 14 and the wafer 20 at the gripping position to be greater than 0.1 mm, it can match the manufacturing tolerance of the equipment, thereby increasing the effectiveness of detection.
[0046] In some embodiments, the deposition system 1 further includes a gripping device 15, which is used to transfer the wafer 20 in the process chamber 111, and the detection device 14 is installed on the gripping device 15. In some embodiments, a film transfer port is provided on one side of the process chamber 111 for the gripping device 15 to extend into the process chamber 111. The gripping device 15 may be, for example, a manipulator or a clamping fixture. The process chamber 111 requires sufficient cleanliness and good sealing performance. And the process chamber 111 needs to be heated to a higher temperature. The installation of the detection device 14 may affect the cleanliness and sealing. And high temperature is also a great challenge for the detection device 14 itself. Since the gripping device 15 can accurately grasp the wafer 20 according to PLC control, the detection device 14 is installed on the gripping device 15, which can avoid the detection device 14 being installed in the process chamber 111 without losing the accuracy of the position of the detection device 14. That is, the gripping device 15 can move the detection device 14 to a set position when gripping, so that the optical path is lower than the wafer 20 at the gripping position. During the process, the detection device 14 can follow the gripping device 15 out of the process chamber 111 to reduce the impact on the process.
[0047] In some embodiments, the detection device 14 is separately provided, and when it is necessary to detect the wafer 20 in the process chamber 111, the detection device 14 can be used to detect the position of the wafer 20 in the process chamber 111 through the wafer transfer port. Through the detection of the detection device 14, it can be confirmed whether the placement of the wafer 20 is normal. If it is detected that the placement is abnormal, a corresponding prompt can be issued. If it is detected that the placement is normal, the wafer 20 can be transferred by the gripping device 15.
[0048] Optionally, when the transmitter and the receiver need to be arranged relative to each other, one of the transmitter and the receiver of the detection device 14 is installed on the device body 11, and the other is installed on the grasping device 15. When the transmitter and the receiver need to face the same direction, the transmitter and the receiver of the detection device 14 are both installed on the grasping device 15.
[0049] Combination Figure 1 and Figure 4 In some embodiments, the detection device 14 can be raised and lowered in the first position (combined with Figure 1 ) and the second position (combined Figure 4). The first position is higher than the second position. When the support 13 is in the supporting position and the detection device 14 is in the first position. The upper surface of the support 13 is lower than the optical path of the detection device 14, and when the support 13 is in the supporting position and the detection device 14 is in the second position, the upper surface of the support 13 is higher than the optical path of the detection device 14. When the detection device 14 is in the first position, the wafer 20 can block the optical path of the detection device 14. In this case, the detection device 14 can be in the first position first, and then in the second position. If the wafer 20 is placed normally, the detection device 14 should block the optical path when it is in the first position, and should not block the optical path when it is in the second position.
[0050] In this way, the first position and the second position can verify the placement of the wafer in the deposition system 1. If an obstruction different from the above situation occurs, it means that the deposition system 1 is abnormal, and timely adjustments are made. The obstruction different from the above situation includes detecting that the light path is blocked at both the first position and the second position, not detecting that the light path is blocked at both the first position and the second position, and not detecting an obstruction at the first position, but detecting an obstruction at the second position. If the above situation occurs, the positioning of the support 13 and the stage 12 may be abnormal, or the detection device 14 may be abnormal. By verifying the first position and the second position, the operator can be prompted to check the position of the support 13 and the stage 12 or the detection device 14 itself.
[0051] On the other hand, when the detection device 14 is in the second position and the wafer 20 is placed normally, it should be the edge of the wafer 20 that blocks the light path, which is different from the blocking of the light path after the wafer 20 is tilted. When the detection device 14 is in the second position and the wafer 20 is placed normally, the distance between the edge of the wafer 20 and the detection device 14 is smaller than the distance between the blocking part of the wafer 20 and the detection device 14 after the wafer 20 is tilted. Therefore, the addition of the second position can also evaluate the placement of the wafer 20 from another angle, so as to detect the abnormal state of the wafer 20 in time.
[0052] In some embodiments, the height difference between the optical path of the detection device 14 at the first position and the optical path of the detection device 14 at the second position is less than 1 mm, for example, 0.1 mm, 0.3 mm, 0.5 mm, 0.7 mm or 0.9 mm.
[0053] After the support member 13 is switched between the first position and the second position and the detection device 14 passes the verification, it is possible to detect whether the wafer 20 is tilted in the manner described in the above embodiment, so as to timely confirm whether the support member 13 is broken.
[0054] The following is an example of a process.
[0055] After the coating process of the previous wafer 20 is completed, the carrier 12 can be lowered to correspond to the film transfer port and be in the film transfer position. At this time, the support member 13 rises relative to the carrier 12 and is in the supporting position to support the wafer 20. At this time, the gripping device 15 can extend into the process chamber 111 to transfer the wafer 20 that has been coated, and the wafer 20 to be coated can be placed in the process chamber 111. After the above steps, the carrier 12 can rise to the position of the coating process, and the support member 13 descends relative to the carrier 12 to place the wafer 20 in the process position for coating. In the process of placing and removing the wafer 20, the following wafer 20 placement detection method can be used.
[0056] Combination Figure 5 , the embodiment of the present application provides a wafer placement detection method:
[0057] S100: Verification:
[0058] The verification steps include:
[0059] S110: Move the carrier 12 to the wafer transfer position, and extend the support member 13 so that the wafer 20 can be in the grasping position, and place the correctly positioned test wafer 12 at the grasping position.
[0060] Before the process is carried out, it is necessary to verify whether the detection device 14 can normally detect the placement of the wafer. In this case, the test wafer can be placed in the process chamber 111, and the detection device 14 can detect whether the test wafer is placed normally. Among them, whether the placement of the test wafer is normal can be carried out by manual detection or other methods to ensure that the test wafer is placed normally. The detection device 14 can detect whether the detection result of the detection device 14 is valid by detecting the normally placed wafer 20 to determine whether the detection result of the normal placement can be obtained.
[0061] S120: Move the detection device 14 to a first position so that the optical path of the detection device 14 is higher than the upper surface of the support 13 and lower than the upper surface of the test wafer, and obtain a first detection result.
[0062] In the above manner, the optical path of the detection device 14 should be blocked. In the case of normal detection, the first detection result should be that the optical path is blocked. In the case of distance detection, the first detection result should be a distance parameter, which is smaller than the distance parameter in the unblocked case.
[0063] S130: Move the detection device to a second position so that the optical path of the detection device is lower than the upper surface of the support member, and obtain a second detection result.
[0064] In the above manner, the optical path of the detection device 14 should be blocked, and in the case of normal detection, the first detection result should be that the optical path is blocked. In the case where the detection device 14 is a rangefinder, the first detection result should be a distance parameter, which is smaller than the distance parameter in the unblocked case.
[0065] In other embodiments, S130 may be performed first and then S120, that is, the detection device may be first at the second position and then at the first position.
[0066] S140: When the first detection result is occlusion and the second detection result is no occlusion, the verification is successful; in other cases, the verification fails.
[0067] Whether the detection device 14 can work normally can be determined by judging the first detection result and the second detection result. If the first detection result is blocked and the second detection result is not blocked, and the wafer 20 is placed normally, it means that the verification is successful. If the first detection result is not blocked and the second detection result is not blocked, it means that the detection device 14 cannot detect normally.
[0068] S141: In case of verification failure, output troubleshooting information and restart the above verification steps.
[0069] If the verification fails, the operator needs to recheck the deposition system 1 to eliminate the fault. After that, the detection device 14 can be re-verified in the above-mentioned manner to see if it can detect normally.
[0070] S142: If the verification is successful, perform routine detection steps.
[0071] If the verification is successful, it means that the detection device 14 can perform detection normally, and the deposition system 1 can perform subsequent process steps. Before and after the wafer 20 is transferred, conventional detection steps can be used to detect whether the wafer is placed normally.
[0072] S200: Routine testing, the routine testing steps include:
[0073] S210: When wafer position detection is required, the detection device 14 is set at the second position to obtain a third detection result.
[0074] When the detection device 14 is in the second position, the third detection result may be that the wafer 20 is placed normally, and the detection light path is not blocked. The third detection result may also be that the wafer 20 is placed tilted, and the detection light path is blocked.
[0075] S220: Determine whether the third detection result is occlusion.
[0076] S221: When the third detection result is obstruction, output the result that the wafer 20 is placed abnormally.
[0077] If the third detection result is an obstruction, the result of abnormal wafer placement needs to be output to the operator or the gripper 15 to promptly troubleshoot the deposition system 1 or prevent the gripper 15 from gripping a tilted wafer 20 to avoid possible breakage of the wafer 20.
[0078] S222: When the third detection result is that there is no obstruction, output the result that the wafer 20 is placed normally.
[0079] If the third detection result is no obstruction, the result that the wafer 20 is placed normally can be output, and the next process step can be performed. For example, the gripping device 15 can transfer the wafer 20 or the stage 112 can rise to carry the wafer 20 .
[0080] In summary, when the support 13 is normal, the detection device 14 receives the reflected signal and the calculated distance is guaranteed to be within the normal range, indicating that the support 13 is normal and the wafer 20 is placed normally. When the support 13 is broken or the wafer 20 is placed eccentrically, the wafer 20 will tilt to one side, causing the detection device 14 to fail to receive the reflected signal or the monitored distance is not within the normal range, indicating that the wafer 20 is placed abnormally. By setting the movement of the carrier 12 so that the support 13 can be in the first position and the second position, and the support 13 blocks the light path of the wafer 20 in the first position, and when the carrier 12 rises and the support 13 is in the second position, the detection device 14 and the equipment can be calibrated to ensure the normal operation of the deposition system 1.
[0081] The above are merely embodiments of the present application and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.
Claims
1. A deposition system, characterized in that: include: An equipment body, wherein a process cavity is formed in the equipment body; A carrier, disposed in the process chamber; Support members, at least three of which are movably disposed on the stage, and at least three of which are used to support the wafer to a grasping position; The detection device is used to detect whether there is an obstruction on the optical path, and the optical path of the detection device is lower or higher than the wafer at the grasping position.
2. The deposition system according to claim 1, characterized in that: The height difference between the optical path of the detection device and the wafer at the gripping position is less than 1 mm.
3. The deposition system according to claim 1, characterized in that: The detection device is arranged separately from the equipment body.
4. The deposition system according to claim 1, characterized in that: The deposition system further comprises a grabbing device, which is used to transfer the wafer in the process chamber, and the detection device is installed on the grabbing device.
5. The deposition system according to claim 4, characterized in that: When the wafer is in the grasping position, the detection device can switch between the first position and the second position by lifting; the first position is higher than the second position; when the detection device is in the first position, the upper surface of the support is lower than the optical path of the detection device, and the wafer blocks the light path; when the detection device is in the second position, the upper surface of the support is higher than the optical path of the detection device.
6. The deposition system according to claim 5, characterized in that: The height difference between the optical path of the detection device at the first position and the optical path of the support member at the second position is less than 1 mm.
7. The deposition system according to claim 1, characterized in that: The detection device comprises a transmitter and a receiver, wherein the receiver is used to receive the light emitted by the transmitter and then reflected; the transmitter and the receiver are arranged in opposite directions, or the transmitter and the receiver face the same direction.
8. The deposition system according to claim 1, characterized in that: A film conveying port is arranged on one side of the process chamber, for allowing a grabbing device to extend into the process chamber.
9. A wafer placement detection method, characterized in that: Verification, including: The stage is moved to the wafer transfer position, and the support member is extended so that the wafer can be in the gripping position, and the test wafer with the correct position is placed at the gripping position; Move the detection device to a first position so that the optical path of the detection device is higher than the upper surface of the support member and lower than the upper surface of the test wafer, and obtain a first detection result; Move the detection device to a second position so that the optical path of the detection device is lower than the upper surface of the support member, and obtain a second detection result; When the first detection result is occlusion and the second detection result is no occlusion, the verification is successful; in other cases, the verification fails; In case of verification failure, output the information of troubleshooting and restart the above verification steps; If the verification is successful, proceed to the normal detection steps.
10. The method according to claim 9, characterized in that: The conventional detection steps include When the wafer position needs to be detected, the detection device is set at the second position to obtain a third detection result; determining a third test result; When the third detection result is occlusion, outputting a result that the wafer placement is abnormal; When the third detection result is that there is no obstruction, a result indicating that the wafer is placed normally is output.