Atomic layer deposition equipment
By creating through-holes at the edge of the wafer placement station in the atomic layer deposition equipment and adding laser sensors, the problems of uneven coating and material waste caused by wafer position misalignment were solved, enabling timely detection and prevention of equipment damage and reducing costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- QINGDAO SIFANG SRI INTELLECTUAL TECHNOLOGY CO LTD
- Filing Date
- 2025-05-19
- Publication Date
- 2026-05-19
AI Technical Summary
In atomic layer deposition equipment, there is a risk of wafer misalignment on the workpiece disk, which can lead to problems such as uneven coating, transfer errors, wafer breakage, and material waste. Existing technologies are difficult to detect and prevent in a timely manner.
At least three through holes are opened at the edge of each wafer placement station on the workpiece tray, and a laser sensor is added. The laser sensor and the through holes work together to form a device for detecting wafer offset. The laser sensor projects a beam of light and determines whether the wafer is offset based on the reflection result.
This enables timely detection of wafer position deviations during the process, avoiding material waste and equipment damage, and reducing operating and maintenance costs.
Smart Images
Figure CN224258777U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of general control or regulation systems, and more particularly to an atomic layer deposition apparatus. Background Technology
[0002] In spatial atomic layer deposition (ALD) equipment, the workpiece disk within the cavity is a rotating mechanism that processes six wafers at a time. During the process, the workpiece disk rotates at a constant angular velocity. Due to factors such as centrifugal force and purge gas pressure, and the instability in pressure caused by the gas source within the cavity during acceleration / deceleration and after reaching a constant velocity, there is a risk of wafer displacement (or deviation) on the workpiece disk. Excessive displacement may lead to wafer breakage, uneven deposition, and other problems. Therefore, how to promptly detect wafer displacement on the workpiece disk is a critical issue that needs to be addressed in semiconductor chip manufacturing. Utility Model Content
[0003] This application provides an atomic layer deposition apparatus capable of timely detecting whether there is a positional shift in the wafer on the workpiece disk. The technical solution is as follows:
[0004] According to one aspect of this application, an atomic layer deposition apparatus is provided, the atomic layer deposition apparatus including a chamber system, a transport system, a gas path system, a drive system, a laser sensor and a target controller, the chamber system including a spray device and a workpiece tray, the workpiece tray including at least one wafer placement station, each wafer placement station having at least three vias on its edge, and the number of laser sensors deployed being consistent with the number of vias provided on each wafer placement station;
[0005] The transmission system is used to transfer the wafer to be processed to the wafer placement station on the workpiece tray, and each wafer placement station is used to place a single wafer;
[0006] The workpiece disk rotary motor in the drive system is used to drive the workpiece disk to rotate at a preset speed.
[0007] The gas path system is used to inject a precursor into the chamber system, the precursor being deposited on the wafer surface of each of the rotating wafers via the spray device;
[0008] The laser sensor is used to project a target beam into the via and output an obstruction detection signal, which is used to indicate whether the via is obstructed by the wafer.
[0009] The target controller is used to determine whether the wafer is offset from the wafer placement station based on the occlusion detection signal.
[0010] The beneficial effects of the technical solutions provided in this application include at least the following:
[0011] By structurally improving each wafer placement station in the workpiece tray—by creating at least three vias on the edge of each station and adding a laser sensor to the original atomic layer deposition equipment—a detection device is formed to detect whether the wafer has shifted off-station. During the actual process, the laser sensor projects a target beam onto the vias. Based on the reflection of the target beam, the laser sensor can distinguish whether the via is blocked by the wafer, thus outputting a corresponding blocking detection signal. This allows the target controller to determine whether the wafer has shifted off-station based on different blocking detection signals. This achieves the goal of timely detection of wafer shift during the process, enabling timely interruption of the process and avoiding waste of precursor and wafer materials caused by continuing the process, as well as preventing further damage to the equipment. Attached Figure Description
[0012] Further details, features, and advantages of this application are disclosed in the following description of exemplary embodiments in conjunction with the accompanying drawings, in which:
[0013] Figure 1 This is a schematic diagram of the device structure of the ALD device provided in the embodiments of this application;
[0014] Figure 2 This is a schematic diagram of the offset detection result provided in an exemplary embodiment of this application;
[0015] Figure 3 This is a schematic diagram of a position offset detection process provided in an exemplary embodiment of this application;
[0016] Explanation of icon numbers:
[0017] 110-Cavity system; 120-Transmission system; 130-Pneumatic system; 140-Drive system; 150-Laser sensor; 160-Target controller; 111-Spray device; 112-Workpiece tray; 113-Wafer placement station; 114-Through hole. Detailed Implementation
[0018] Embodiments of this application will now be described in more detail with reference to the accompanying drawings. While some embodiments of this application are shown in the drawings, it should be understood that this application can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this application. It should be understood that the drawings and embodiments of this application are for illustrative purposes only and are not intended to limit the scope of protection of this application.
[0019] It should be understood that the steps described in the method embodiments of this application may be performed in different orders and / or in parallel. Furthermore, the method embodiments may include additional steps and / or omit the steps shown. The scope of this application is not limited in this respect.
[0020] The term "comprising" and its variations as used herein are open-ended, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Definitions of other terms will be given in the following description. It should be noted that the concepts of "first", "second", etc., mentioned in this application are only used to distinguish different devices, modules, or units, and are not intended to limit the order of functions performed by these devices, modules, or units or their interdependencies. It should be noted that the modifications "a" and "a plurality" mentioned in this application are illustrative and not restrictive, and those skilled in the art should understand that unless explicitly indicated in the context, they should be understood as "one or more". The names of messages or information exchanged between multiple devices in the embodiments of this application are for illustrative purposes only and are not intended to limit the scope of these messages or information.
[0021] The present invention will now be described with reference to the accompanying drawings. The technical solutions provided by the embodiments of the present invention will be explained in detail through specific examples and application scenarios.
[0022] In spatial atomic layer deposition (ALD) equipment, the workpiece disk within the cavity is a rotating mechanism that processes six wafers at a time. During the process, the workpiece disk rotates at a constant angular velocity. Due to factors such as centrifugal force and purge gas pressure, and under conditions of pressure instability caused by the gas source within the cavity during acceleration / deceleration and after reaching a constant velocity, there is a risk of wafer displacement (or deviation) on the workpiece disk. This risk can easily lead to the following effects:
[0023] (1) When the position is too large, the transmission robot may make a transmission error or even collide with the wafer, which may cause damage to the equipment. In severe cases, it may lead to wafer breakage, affecting operating costs and running costs.
[0024] (2) When the position is offset, the wafer may be rated as defective due to uneven surface coating, resulting in waste of precursor and wafer materials.
[0025] (3) If the problem is not detected in time when the position is off, it will also cause a waste of production time and cost.
[0026] To enable timely detection of wafer misalignment on the workpiece disk during the manufacturing process, this application improves upon the original ALD (Alternating Displacement) equipment by creating openings at preset positions and adding laser sensors to achieve timely detection of wafer misalignment during the process. Please refer to... Figure 1 , Figure 1 This is a schematic diagram of the device structure of the ALD device provided in the embodiments of this application. For example... Figure 1 As shown, the atomic layer deposition apparatus includes a chamber system 110, a transport system 120, a gas path system 130, a drive system 140, a laser sensor 150, and a target controller 160.
[0027] The chamber system 110 includes a spray device 111 and a workpiece tray 112, the workpiece tray 112 including at least one wafer placement station 113. For example... Figure 1 As shown, the workpiece tray includes six wafer placement stations: STATION1, STATION2, STATION3, STATION4, STATION5, and STATION6, i.e., STATION1 to STATION6. Optionally, each wafer placement station is used to place a single wafer.
[0028] In actual manufacturing processes, after a wafer is placed in each wafer placement station, the workpiece tray rotates at a set speed. However, due to factors such as centrifugal force and purge gas pressure, the wafer may deviate from its designated wafer placement station, leading to problems such as uneven wafer coating, transport errors, and wafer breakage. Therefore, to detect wafer positional deviation during actual manufacturing processes, it is crucial to determine whether the wafer has deviated from its designated wafer placement station. In this embodiment, a structural improvement is made to each wafer placement station in the workpiece tray: at least three through-holes are opened on the edge of each wafer placement station, and a laser sensor is added to the original atomic layer deposition equipment. This laser sensor, in conjunction with the three through-holes on the wafer placement station, forms a detection device to determine whether the wafer has deviated from its designated wafer placement station. Specifically, the detection principle of this device is as follows: After setting at least three vias at the edge of each wafer placement station, a laser sensor projects a target beam into the vias. If the wafer deviates from the wafer placement station, it will inevitably block at least one via, causing the target beam to be reflected before passing through the via. The laser sensor detects a shorter distance based on the reflected light of the projected target beam. If the wafer does not deviate from the wafer placement station, it will not block any via, allowing the target beam to pass through. The laser sensor detects a longer distance based on the reflected light of the projected target beam. Based on the difference in detection distance, the laser sensor can distinguish whether the via is blocked by the wafer, thereby outputting a corresponding blocking detection signal. This allows the target controller to determine whether the wafer has deviated from the wafer placement station based on different blocking detection signals.
[0029] Since each wafer placement station has at least three vias, and the wafer's deviation direction is unknown, a laser sensor is installed in each via to ensure the accuracy of detecting unknown wafer offset. That is, the number of laser sensors deployed is the same as the number of vias in each wafer placement station. For example, if each wafer placement station has three vias, three laser sensors need to be deployed so that each laser sensor can project a target beam onto its corresponding via.
[0030] Furthermore, considering the offset position of the wafer, when at least three vias are opened at the edge of the wafer placement station, it is necessary to ensure that at least one via is blocked when the wafer is offset from the wafer placement station. For example, if four vias are opened at the edge of the wafer placement station, the four vias are used to divide the perimeter of the wafer placement station into four equal parts. Conversely, it is also necessary to ensure that no via is blocked by the wafer when it is not offset from the wafer placement station. As shown in Figure 1, the wafer placement station 113 has four vias 114.
[0031] Based on the above improvements to the atomic layer deposition equipment (opening vias at the edge of the wafer placement station + adding laser sensors matching the number of vias), the inspection process of the new atomic layer deposition equipment in actual process is as follows:
[0032] The transfer system 120 is used to transfer the wafer to be processed to the wafer placement station 113 on the workpiece tray 112, and each wafer placement station 113 is used to place a single wafer.
[0033] In one possible embodiment, the transmission system mainly includes a transmission robot ( Figure 1 In the process described in section ①ROBOT, before the process begins, the workpiece tray rotates STATION1 to the workpiece tray pick-up position, the PIN tray is lifted, the chamber door opens, and the transfer robot transfers the wafer into the chamber and places it on the PIN tray before retracting. The PIN tray then descends, placing the wafer on the wafer placement station - STATION1. This process is repeated until STATION1 to STATION6 on the workpiece tray are filled with wafers. In other words, the transfer robot in the transfer system sequentially transfers wafers to multiple wafer placement stations on the workpiece tray, with each wafer placement station holding a single wafer. After placement is complete, the chamber door closes.
[0034] The workpiece disk rotary motor in the drive system 140 is used to drive the workpiece disk to rotate at a preset speed.
[0035] After the wafer transfer is completed, the workpiece disk rotation motor in the drive system starts to operate, driving the workpiece disk to rotate until it reaches the set speed. Then the workpiece disk rotates at the set speed to start the subsequent process flow.
[0036] Optionally, the drive system also includes a PIN lifting motor for controlling the lifting and lowering of the tray during wafer transfer to place the wafer in the wafer placement station.
[0037] The gas path system 130 is used to inject precursors into the chamber system 110, and the precursors are deposited on the wafer surface of each rotating wafer by the spray device 111.
[0038] The gas path system includes a precursor, a carrier gas, and an inert gas, and is connected to the chamber system. It is used to inject the precursor into the chamber system. The precursor is deposited on the surface of each rotating wafer through the spray device of the chamber system to form a monolayer adsorption layer on the substrate surface.
[0039] For example, such as Figure 1 As shown, precursors A and B are introduced into different regions of the chamber, and inert gas is introduced into these regions as well. The precursors are deposited onto the surface of the rotating workpiece disk wafer via a spraying device, forming a single-layer adsorption layer on the substrate surface. After the inert gas is introduced, unadsorbed precursor molecules and byproducts are cleaned and purged, and then discharged from the reaction chamber through a vacuum system. Each rotation of the workpiece disk constitutes one cycle, forming one atomic layer. After rotating for a set value of N revolutions, the process requirements are met, and the process is complete.
[0040] The laser sensor 150 is used to project a target beam into the via and to output an obstruction detection signal, which is used to indicate whether the via is obstructed by the wafer.
[0041] During the process of rotating the workpiece disk, in order to detect in a timely manner whether the wafer has deviated from its wafer placement station, the laser sensor projects a target beam into the via and then outputs an obstruction detection signal to indicate whether the via is blocked by the wafer based on the reflection result of the target beam.
[0042] Specifically, when the via is not blocked by the wafer, the blocking detection signal output by the laser sensor is the first detection signal, such as "true," indicating that the wafer has not shifted from the wafer placement station. When the via is blocked by the wafer, the blocking detection signal output by the laser sensor is the second detection signal, such as "false," indicating that the wafer has shifted from the wafer placement station. This allows the target controller (PLC) to determine whether the wafer has shifted from its wafer placement station based on different blocking detection signals.
[0043] Because the positions of the wafer placement stations in the workpiece tray are different, in order to distinguish between different wafer placement stations and further identify which wafer has an offset problem during the actual process, it is necessary to obtain the rotation angle range corresponding to the laser sensor mounting position of each wafer placement station before proceeding with the process flow. In one possible embodiment, when no wafers are placed in the workpiece tray, the workpiece tray rotary motor is also used to drive each wafer placement station in the workpiece tray to rotate to the target position where the laser sensor outputs the first detection signal, and to record the rotation angle range of the workpiece tray rotary motor when rotating to the target position. Different wafer placement stations correspond to different rotation angle ranges. Specifically, when a wafer placement station rotates to the position where multiple laser sensors simultaneously output the first detection signal, it indicates that the wafer placement station has moved to the mounting position of multiple laser sensors, allowing the projected beam of each laser sensor to directly pass through multiple through-holes on the edge of the wafer placement station, enabling multiple laser sensors to simultaneously output the first detection signal (without obstruction).
[0044] For example, the rotation angle range corresponding to each wafer placement station can be shown in Table 1:
[0045] Table 1
[0046] STATION1 STATION 2 STATION 3 STATION 4 STATION 5 STATION 6 5°±1° 65°±1° 125°±1° 185°±1° 245°±1° 305°±1°
[0047] As shown in Table 1, when the encoder feedback value of the workpiece disk rotary motor is 6° > encoder value > 4°, STATION 1 moves to the laser sensor detection range; when the encoder feedback value is 66° > encoder value > 64°, STATION 2 moves to the laser sensor detection range; when the encoder feedback value is 126° > encoder value > 124°, STATION 3 moves to the laser sensor detection range; when the encoder feedback value is 186° > encoder value > 184°, STATION 4 moves to the laser sensor detection range; when the encoder feedback value is 246° > encoder value > 244°, STATION 5 moves to the laser sensor detection range; and when the encoder feedback value is 306° > encoder value > 304°, STATION 6 moves to the laser sensor detection range. Here, the encoder value represents the rotation angle of the workpiece disk rotary motor, and the range in which the encoder value is located represents the rotation angle range.
[0048] After obtaining the rotation angle range corresponding to the different wafer placement stations rotating to the laser sensor installation position, it can be transmitted to the target controller (PLC) so that the target controller can acquire and store the rotation angle range corresponding to each wafer placement station for subsequent determination of wafer position offset.
[0049] Since wafer placement stations correspond to different rotation angle ranges, and the occlusion detection signal output by the laser sensor is only valuable within these ranges, to reduce the power consumption of the laser sensor, it can be controlled to project the target beam only within these rotation angle ranges. In some possible embodiments, the target controller can also control the laser sensor to project the target beam into the via within each rotation angle range corresponding to each wafer placement station; outside of these rotation angle ranges, the laser sensor can stop projecting the target beam to reduce its power consumption.
[0050] For example, taking the rotation angle range shown in Table 1 as an example, the target controller can control the laser sensor to project the target beam within the range of the workpiece disk rotary motor's encoded values of 4°~6°, 64°~66°, 124°~126°, 184°~186°, and 244°~246° respectively; while at other encoded values, the projection of the target beam can be stopped.
[0051] Each laser sensor projects a target beam into the via at each rotation angle interval and outputs a corresponding occlusion detection signal based on the reflection result of the target beam. The corresponding target controller can receive the occlusion detection signal output by the laser sensor in each rotation angle interval. Then, the target controller can determine whether the wafer has deviated from the wafer placement station corresponding to the rotation angle interval based on the correspondence between each occlusion detection signal, the rotation angle interval, and the wafer placement position.
[0052] For example, taking a wafer placement station 1 (i.e., STATION 1) with 4 vias and 4 laser sensors, laser sensors 1 to 4 project target beams into the vias of wafer placement station 1 at angles of 4° to 6° respectively, and output 4 occlusion detection signals based on the reflection results of the target beams. If all 4 occlusion detection signals are first detection signals, it means that none of the 4 vias of wafer placement station 1 are occluded and the wafer has not deviated from wafer placement station 1; if at least one of the 4 occlusion detection signals is a second detection signal, it means that at least one of the 4 vias of wafer placement station 1 is occluded by the wafer and the wafer has deviated from wafer placement station 1.
[0053] Because the chamber system operates under vacuum, the laser sensor may not function properly. Therefore, the laser sensor is located outside the chamber system. To allow the laser sensor to project the target beam into the vias within the chamber system, multiple transparent glass panes, sufficient to meet vacuum requirements, are installed in the original atomic layer deposition equipment. These panes allow the target beam projected by each laser sensor to pass through the transparent glass and through multiple vias on the wafer placement station. In other words, the transparent glass panes are installed along the propagation path of the target beam projected by the laser sensor into the vias, and the number of transparent glass panes is the same as the number of laser sensors deployed, ensuring that each laser sensor can project its target beam into the via through its corresponding transparent glass pane.
[0054] The target controller 160 is used to determine whether the wafer is offset from the wafer placement station based on the occlusion detection signal.
[0055] Based on the above description, the target controller can receive the occlusion detection signal output by the laser sensor and determine whether the wafer has shifted off-center from the wafer placement station based on the occlusion detection signal. Since each wafer placement station corresponds to a rotation angle range, when the workpiece disk rotates to each rotation angle range, the target controller can acquire the occlusion detection signal within that rotation angle range and determine whether a second detection signal exists within the occlusion detection signal. If at least one second detection signal is acquired, the target controller determines the wafer placement station corresponding to the wafer shifted off-center from the rotation angle range; if no second detection signal is acquired, the target controller determines the wafer placement station corresponding to the wafer not shifted off-center from the rotation angle range.
[0056] To distinguish between wafers with offset issues and normal wafers, the target controller will set an anomaly flag for the target wafer at the offset wafer placement station when it determines that the wafer has a positional offset; or, it will set an anomaly flag for the wafer placement station itself.
[0057] When a wafer misalignment or abnormal marking is detected, the target controller will immediately stop the pneumatic and drive systems to avoid wasting precursors during process continuity, and transmit an alarm signal to the host computer. This alarm signal may include the wafer placement station or wafer with the abnormal marking, allowing the user to view the wafer with the abnormal marking via the host computer.
[0058] Please refer to Figure 2 This is a schematic diagram of the offset detection result marker provided in an exemplary embodiment of this application. For example... Figure 2 As shown, if the wafer on wafer placement station 1 in the workpiece tray has a positional offset, a gray mark (abnormal mark) will be added to wafer placement station 1 in the workpiece tray.
[0059] After the control air system and drive system stop working, the transfer system is also used to remove wafers except for those marked with anomalies. Wafers with anomalies need to be handled manually to avoid loss of equipment and wafers due to wafer misalignment.
[0060] For example, taking a workpiece tray containing 6 wafer placement stations as an example, if a wafer on wafer placement station 1 is detected to have a positional offset, the host computer will alarm and interrupt the process. At this time, the transfer robot in the transfer system will automatically remove all wafers on the workpiece tray except for wafer placement station 1, and the remaining wafers on wafer placement station 1 will wait for manual operation.
[0061] In summary, this application embodiment improves the structure of each wafer placement station in the workpiece tray by creating at least three vias on the edge of each station and adding a laser sensor to the original atomic layer deposition equipment. This laser sensor, in conjunction with the at least three vias on the wafer placement station, forms a detection device to detect whether the wafer has shifted off the wafer placement station. During the actual process, the laser sensor projects a target beam onto the vias, and based on the reflection of the target beam, the laser sensor can distinguish whether the vias are blocked by the wafer, thus outputting a corresponding blocking detection signal. This allows the target controller to determine whether the wafer has shifted off the wafer placement station based on different blocking detection signals. This achieves the goal of timely detection of wafer shift during the process, allowing for timely interruption of the process and avoiding waste of precursor and wafer materials caused by continuing the process, as well as preventing further damage to the equipment.
[0062] Please refer to Figure 3 This is a schematic diagram of a position offset detection process provided in an exemplary embodiment of this application. Figure 3 As shown, the testing process is as follows:
[0063] a. When the workpiece disk rotates, the PLC determines whether the signals of the four newly added laser sensors are all true when the wafers of STATION1 to 6 pass by.
[0064] After the transfer robot feeds six wafers onto the workpiece tray, the process begins, and the workpiece tray rotates. During the rotation, when each wafer placement station X rotates into the laser sensor's position range, the PLC determines whether wafer placement station X is marked. If not marked, it checks whether all four laser sensor signals are true. If all are true, the workpiece tray continues to rotate; if not all are true, meaning any laser sensor signal is false, the process pauses, and the host computer issues an alarm signal.
[0065] b. When STATION1 to STATION6 move sequentially to the laser sensor mounting positioner interval, if any one or more laser sensors detect a false signal, the process is immediately paused, the input of the precursor is stopped, the host computer alarms, and the current STATIONX (wafer placement station X) is marked as abnormal.
[0066] c. After receiving an alarm from the host computer, the technician restores the equipment on-site and determines whether the process can continue.
[0067] d. If the process is terminated due to an abnormality, the process will stop, and the ROBOT will automatically remove the unmarked wafers from the STATION in sequence. The marked wafers will need to be handled manually by the transfer robot.
[0068] If the technician restores the equipment and selects process continuation, the workpiece tray rotation continues. This application overcomes the shortcomings of existing ALD equipment, which suffers from wasted precursors and equipment damage due to the failure to detect wafer offset in a timely manner during the process, allowing for timely problem detection and preventing greater losses. When a wafer on a wafer placement station in the workpiece tray is detected to be offset, the host computer alarms and marks it in gray. At this point, the technician determines whether the process can continue and confirms on the host computer. Wafers on unmarked wafer placement stations are automatically returned, while marked wafers are handled manually, avoiding equipment damage and wafer breakage caused by wafer offset.
Claims
1. An atomic layer deposition apparatus, characterized in that, The atomic layer deposition equipment includes a chamber system, a transport system, a gas path system, a drive system, laser sensors, and a target controller. The chamber system includes a spray device and a workpiece tray. The workpiece tray includes at least one wafer placement station. Each wafer placement station has at least three vias on its edge. The number of laser sensors deployed is the same as the number of vias on each wafer placement station. The transmission system is used to transfer the wafer to be processed to the wafer placement station on the workpiece tray, and each wafer placement station is used to place a single wafer; The workpiece disk rotary motor in the drive system is used to drive the workpiece disk to rotate at a preset speed. The gas path system is used to inject a precursor into the chamber system, the precursor being deposited on the wafer surface of each of the rotating wafers via the spray device; The laser sensor is used to project a target beam into the via and output an obstruction detection signal, which is used to indicate whether the via is obstructed by the wafer. The target controller is used to determine whether the wafer is offset from the wafer placement station based on the occlusion detection signal.
2. The atomic layer deposition apparatus according to claim 1, characterized in that, When the via is not blocked by the wafer, the blocking detection signal output by the laser sensor is the first detection signal; When the via is blocked by the wafer, the blocking detection signal output by the laser sensor is a second detection signal.
3. The atomic layer deposition apparatus according to claim 2, characterized in that, When no wafer is placed in the workpiece tray, the workpiece tray rotary motor is also used to drive each wafer placement station in the workpiece tray to rotate to the target position where the laser sensor outputs the first detection signal, and to determine the rotation angle range of the workpiece tray rotary motor when rotating to the target position, with different wafer placement stations corresponding to different rotation angle ranges; The target controller is used to acquire and store the rotation angle range corresponding to each of the wafer placement stations.
4. The atomic layer deposition apparatus according to claim 3, characterized in that, The target controller is also configured to control the laser sensor to project the target beam into the through-hole in each rotation angle range according to the rotation angle range; The target controller is also used to acquire the occlusion detection signal within each of the rotation angle intervals.
5. The atomic layer deposition apparatus according to claim 4, characterized in that, The target controller is also used to determine whether the wafer is offset from the wafer placement station corresponding to the rotation angle interval based on the occlusion detection signal within each rotation angle interval.
6. The atomic layer deposition apparatus according to claim 5, characterized in that, For each rotation angle interval, if at least one of the second detection signals is obtained, the target controller is further configured to determine the wafer placement station corresponding to the wafer offset from the rotation angle interval; If the second detection signal is not acquired for each rotation angle interval, the target controller is further configured to determine that the wafer has not deviated from the wafer placement station corresponding to the rotation angle interval.
7. The atomic layer deposition apparatus according to claim 6, characterized in that, The target controller is also used to set an anomaly flag for a target wafer that is offset from the wafer placement station.
8. The atomic layer deposition apparatus according to claim 7, characterized in that, Upon detecting the abnormal marker, the target controller is also used to control the pneumatic system and drive system to stop working, and to transmit an alarm signal to the host computer.
9. The atomic layer deposition apparatus according to claim 7, characterized in that, After the gas path system and the drive system stop working, the transmission system is also used to remove the wafers except for the abnormal markings.
10. The atomic layer deposition apparatus according to any one of claims 1 to 9, characterized in that, The atomic layer deposition apparatus further includes transparent glass, which is mounted on the propagation path of the target beam projected by the laser sensor, and the number of transparent glass is the same as the number of laser sensors deployed. The laser sensor is also used to project the target beam through the transparent glass into the through-hole.