Wafer transmission monitoring system and wafer transmission monitoring method

Abstract

The invention provides a wafer transfer monitoring system and a wafer transfer monitoring method, the wafer transfer monitoring system comprises a wafer bearing device, an emission sensing device, a transfer device and a processing system, the wafer bearing device is used for bearing a plurality of wafers, the transfer device is used for taking and conveying the wafers in the wafer bearing device, and the processing system is used for processing the wafers in the wafer bearing device. The emission sensing device is arranged on the wafer bearing device, can generate a light beam parallel to the wafer near each wafer, is connected with the processing system and outputs an electric signal to the processing system in real time according to the transmission condition of the light beam under the interference of the transmission device, and the processing system monitors whether the wafer transmission is normal or not according to the electric signal; and an alarm is given out when the wafer is abnormal, so that the mechanical arm can be monitored in real time in the wafer conveying process, and the abnormal conveying condition in the conveying process is avoided.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to a wafer transfer monitoring system and a wafer transfer monitoring method. Background Art

[0002] Ion implanters are primarily used in the ion implantation process within semiconductor manufacturing. During the ion implantation process, the ion implanter uses a magnetic field to screen an ion beam with the required charge. It then accelerates or decelerates the ion beam using a DC voltage to impart the appropriate energy. Finally, the ion beam is implanted into the substrate at the appropriate dose, angle, and depth, thereby altering the electrical properties of the substrate material. Currently, mainstream ion implanters utilize single-wafer implantation systems, characterized by high implantation accuracy and high single-wafer speeds. Consequently, a single machine can produce thousands of wafers per day, placing high demands on wafer transport accuracy and stability.

[0003] like Figure 1 As shown, during the wafer transfer process, the dual-arm transfer robot arm 21 picks and places the wafer from the wafer loader 1 into the wafer vacuum loading chamber 3. The vacuum transfer robot arm 22 then picks and places the wafer from the wafer vacuum loading chamber 3 into the process chamber 4 of the ion implanter. Since the wafer picking space position of the robot arm (i.e., the dual-arm transfer robot arm and the vacuum transfer robot arm) in the wafer loader 1 or the wafer vacuum loading chamber 3 is set according to the robot arm technology (i.e., the robot arm position when picking and placing the first wafer), the remaining wafer picking and placing positions are set based on the home point position. Since there is no real-time monitoring system to monitor the robotic arm in real time during the above transmission process, if abnormal transmission conditions such as robotic arm position deviation, wafer jumping, wafer sticking, etc. occur during the transmission process, it is impossible to detect and stop the action in time, resulting in the risk of wafer scratches or even breakage. Summary of the Invention

[0004] The purpose of the present invention is to provide a wafer transfer monitoring system and a wafer transfer monitoring method, which can monitor the robot arm in real time during the wafer transfer process to avoid abnormal transfer situations such as robot arm position deviation, wafer jumping, wafer sticking, etc. during the transfer process.

[0005] In order to solve the above problems, the present invention provides a wafer transmission monitoring system, including a wafer carrying device, an emitting sensing device, a conveying device and a processing system, wherein the wafer carrying device is used to carry multiple wafers, and the conveying device is used to take and deliver the wafers in the wafer carrying device. The emitting sensing device is arranged on the wafer carrying device and can generate a light beam parallel to the wafer near each wafer. The emitting sensing device is connected to the processing system and is used to output an electrical signal to the processing system in real time according to the transmission status of the light beam under the interference of the conveying device. The processing system is used to monitor whether the transmission of the wafer is normal based on the electrical signal and to issue an alarm in case of abnormality.

[0006] Optionally, the emitting and sensing device includes multiple laser emitters and multiple laser sensors, each of the laser emitters is arranged opposite to one of the laser sensors, so that each of the laser emitters can emit a light beam, and each of the laser sensors can receive the light beam emitted by the corresponding laser emitter, and during the process of taking or placing the wafer, output an electrical signal to the processing system in real time according to the reception status of the light beam caused by the position change between the conveying device and the light beam.

[0007] Furthermore, the wafer carrying device includes a plurality of wafer placement positions, all of which are arranged in sequence from bottom to top at fixed intervals, and each of the wafer placement positions can hold a wafer;

[0008] Each of the laser emitters is placed below the wafer on a corresponding wafer placement position, and a longitudinal distance between a light beam emitted by each of the laser emitters and the corresponding wafer is less than 5 mm.

[0009] Furthermore, the number of the laser emitters is the same as the number of the laser sensors and the number of the wafer placement positions.

[0010] Optionally, the diameter of the light beam is within 1 mm, and the transmission speed of the electrical signal is in milliseconds or below.

[0011] Optionally, the processing system includes a data processing module, which generates a data graph in real time according to the electrical signal, and monitors whether the conveying device is normal during the wafer conveying process according to the data graph, and issues an early warning in case of abnormality, and can also control the wafer to stop transmission while issuing an early warning.

[0012] In another aspect, the present invention provides a wafer transfer monitoring method, which uses the wafer transfer monitoring system, comprising the following steps:

[0013] When the conveyor device takes or delivers wafers from the wafer carrier device, the transmitting and sensing device generates a light beam parallel to each wafer near the wafer, and the transmitting and sensing device outputs an electrical signal to the processing system in real time according to the transmission status of the light beam under the interference of the conveyor device;

[0014] The processing system monitors whether the wafer transfer is normal according to the electrical signal and issues an alarm when an abnormality occurs.

[0015] Optionally, the specific steps for the conveyor to remove the wafer are:

[0016] The robotic arm of the conveying device extends into the wafer carrying device and approaches the wafer from below the wafer to be taken, and contacts the corresponding light beam. At this time, the transmission of the light beam is not blocked, and the transmitting sensing device outputs an electrical signal in real time according to the reception status of the light beam;

[0017] The robotic arm continues to approach the wafer and lifts the wafer, and the robotic arm blocks the light beam. At this time, the transmission of the light beam is blocked, and the transmitting sensing device outputs an electrical signal according to the reception status of the light beam.

[0018] The robotic arm continues to move upward and takes out the wafer from the wafer carrying device. The robotic arm does not contact the light beam. At this time, the transmission of the light beam is not blocked. At the same time, the transmitting sensing device outputs an electrical signal in real time according to the light beam reception situation.

[0019] Optionally, the wafer carrying device includes a plurality of wafer placement positions, all of which are arranged in sequence from bottom to top at fixed intervals, and each of the wafer placement positions can hold a wafer. Meanwhile, the specific steps of placing the wafer by the conveying device are as follows:

[0020] The robotic arm of the conveying device holds a wafer to be placed and extends into the wafer carrying device, and gradually approaches the wafer placement position where the wafer is to be placed from above the wafer placement position, and contacts the corresponding light beam. At this time, the transmission of the light beam is not blocked, and the transmitting sensing device outputs an electrical signal in real time according to the reception status of the light beam;

[0021] The robotic arm continues to move downward and places the wafer, and the robotic arm blocks the light beam. At this time, the transmission of the light beam is blocked, and at the same time, the transmitting sensing device outputs an electrical signal according to the light beam reception situation;

[0022] The robotic arm continues to move downward and leaves the wafer carrier, and the robotic arm is not in contact with the light beam. At this time, the light beam transmission is not blocked, and the transmitting sensing device outputs an electrical signal in real time according to the light beam reception situation.

[0023] Optionally, the processing system monitors whether wafer transfer is normal according to the electrical signal in the following steps:

[0024] The data processing module of the processing system generates a data graph in real time according to the electrical signal, and compares the generated data graph with the data graph when the robot arm is in a normal position as a reference. When the generated data graph is abnormal, the processing system issues an early warning in time and controls the wafer to stop transmission.

[0025] Compared with the prior art, the present invention has the following beneficial and unexpected technical effects:

[0026] The present invention provides a wafer transmission monitoring system and a wafer transmission monitoring method. The wafer transmission monitoring system includes a wafer carrying device, an emitting sensing device, a transmission device and a processing system. The wafer carrying device is used to carry multiple wafers, and the transmission device is used to take and send wafers in the wafer carrying device. The emitting sensing device is arranged on the wafer carrying device and can generate a light beam parallel to the wafer near each wafer. The emitting sensing device is connected to the processing system and is used to output an electrical signal to the processing system in real time according to the transmission status of the light beam under the interference of the transmission device. The processing system is used to monitor whether the transmission of the wafer is normal according to the electrical signal and to issue an alarm when an abnormality occurs. The risk of wafer scratches or even wafer breakage caused by abnormalities in the wafer transmission process can be monitored in real time, potential risks can be prevented, and the success rate of wafer transmission is increased. When the transmission is abnormal, an alarm is issued in time and the wafer transmission action is stopped, thereby avoiding the risk of wafer scrapping caused by abnormalities in the transmission device, improving the normal operation time of the machine, and ensuring the quality of the wafer, delaying the stable production time of the machine, and reducing the workload of the on-duty engineer. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The figure is a block diagram of a wafer transfer system.

[0028] Figure 2 A schematic structural diagram of a wafer transfer monitoring system provided by one embodiment of the present invention.

[0029] Figure 3 A schematic diagram of a structure for monitoring normal and abnormal robot arm positions during wafer transfer provided by one embodiment of the present invention.

[0030] Description of reference numerals:

[0031] Figure 1 Middle: 1-wafer loading equipment; 21-double-arm wafer transfer robot; 22-vacuum wafer transfer robot; 3-wafer vacuum loading chamber; 4-process chamber;

[0032] Figure 2-Figure 3 Middle: 10-wafer; 100-wafer carrier; 110-wafer placement position; 120-carrying part; 210-laser emitter; 220-light beam; 230-laser sensor; 300-robotic arm; 400-processing system; 410-data processing module; 500-alarm device. DETAILED DESCRIPTION

[0033] The following is a further detailed description of a wafer transfer monitoring system and wafer transfer monitoring method of the present invention. The present invention will be described in more detail below with reference to the accompanying drawings, which illustrate preferred embodiments of the present invention. It should be understood that those skilled in the art may modify the present invention described herein while still achieving the beneficial effects of the present invention. Therefore, the following description should be understood as a general guideline for those skilled in the art and is not intended to limit the present invention.

[0034] For the sake of clarity, not all features of actual embodiments are described. In the following description, well-known functions and structures are not described in detail because they would obscure the present invention with unnecessary detail. It should be understood that in the development of any actual embodiment, numerous implementation details must be made to achieve the developer's specific goals, such as adapting from one embodiment to another to accommodate system or business constraints. Furthermore, it should be understood that such development work may be complex and time-consuming, but is nevertheless a routine undertaking for those skilled in the art.

[0035] In order to make the purpose and features of the present invention more obvious and easy to understand, the specific embodiments of the present invention are further described below with reference to the accompanying drawings. It should be noted that the drawings are all in a very simplified form and use non-precise ratios, which are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. It should be noted that Figure 3 The first three figures in a are flow charts of the wafer transfer process when the robot arm is in a normal position, and the last figure is a data graph generated after the optical signals of the first three figures are converted into electrical signals; Figure 3 Figures b, c, and d are flow charts of the wafer transfer process when the robot arm is in different abnormal positions, and the last figure is a data graph generated after the optical signals of the first three figures are converted into electrical signals.

[0036] like Figure 2As shown, this embodiment provides a wafer transmission monitoring system, including a wafer carrier 100, an emitting sensing device, a transmission device and a processing system 400, wherein the wafer carrier 100 is used to carry multiple wafers 10, and the transmission device is used to take and deliver the wafers 10 in the wafer carrier 100, and the emitting sensing device is arranged on the wafer carrier 100, and can generate a light beam 220 parallel to the wafer 10 near each wafer 10, and the emitting sensing device is connected to the processing system 400, and is used to output an electrical signal to the processing system 400 in real time according to the transmission status of the light beam 220 under the interference of the transmission device, and the processing system 400 is used to monitor whether the transmission of the wafer 10 is normal according to the electrical signal, and to issue an alarm in case of abnormality.

[0037] The wafer transfer monitoring system of this embodiment can monitor in real time the risk of scratches or even breakage of the wafer 10 caused by abnormalities in the transfer process of the wafer 10, and can prevent potential risks. It also increases the success rate of wafer 10 transfer, and promptly alarms when transmission abnormalities occur, and stops the wafer 10 transfer action, avoiding the risk of wafer 10 scrapping due to abnormalities in the transfer device, improving the normal operation time of the machine, and at the same time ensuring the quality of the wafer 10, delaying the stable production time of the machine, and reducing the workload of the on-duty engineer.

[0038] In detail, the wafer carrier 100 can be a wafer vacuum loading chamber or a wafer loading device. The wafer carrier 100 includes a carrier 120 and a plurality of wafer placement positions 110. The carrier 120 as a whole is a cylindrical structure with an axial through groove. The axial through groove is located on the side wall of the cylindrical structure, so that the cross-section of the cylindrical structure is an open ring. The opening size of the axial through groove is larger than the diameter of the wafer 10, so that the wafer 10 can enter the interior of the carrier 120 through the axial through groove. The plurality of wafer placement positions 110 are arranged in sequence from bottom to top at fixed intervals and fixed on the inner wall of the carrier 120. It should be noted that the axial through groove is a notch located on the side wall of the carrier 120, and the notch passes through the side wall of the carrier 120 along the axial direction of the carrier 120, so that the length of the notch is the same as the axial length of the carrier 120.

[0039] The conveying device may be a dual-arm wafer conveyor or a vacuum wafer conveyor, both of which include a robotic arm 300, and the robotic arm 300 is used to place each wafer 10 on a wafer placement position 110, or to remove each wafer 10 from the corresponding wafer placement position 110. The conveying device can convey one wafer 10 at a time.

[0040] When the wafer carrier 100 is a wafer loading device, the conveying device is a double-arm wafer conveyor, and the conveying device is used to take the wafer 10 out of the wafer loading device and place it in the wafer vacuum loading chamber; when the wafer carrier 100 is a wafer vacuum loading chamber, the conveying device is a vacuum wafer conveyor, and the conveying device is used to take the wafer 10 out of the wafer vacuum loading chamber and place it in the process chamber.

[0041] The emitting and sensing device includes multiple laser emitters 210 and multiple laser sensors 230. Each of the laser emitters 210 is arranged opposite to one of the laser sensors 230, so that each of the laser emitters 210 can emit a light beam 220, and each of the laser sensors 230 can receive the light beam 220 emitted by the corresponding laser emitter 210. In the process of picking up the wafer 10 or placing the wafer 10, the receiving status of the light beam 220 caused by the position change between the robot arm 300 of the conveying device and the light beam 220 is output to the processing system 400 in real time. That is to say, each of the laser sensors 230 is connected to the processing system 400 in parallel, so that the processing system 400 draws a data graph for the electric signal output by each laser sensor 230.

[0042] The diameter of the light beam 220 is within 1 mm, so that when the robot arm 300 takes and places the wafer 10, the emission sensing device can accurately monitor the position change of the wafer, reduce the impact of other factors on the data, and avoid monitoring errors. The transmission speed of the electrical signal is in the millisecond level or below, and the electrical signal can be obtained as uninterruptedly as possible. The number of the laser emitters 210 is the same as the number of laser sensors 230. Furthermore, the number of the laser emitters 210 is the same as the number of wafer placement positions 110, so that each laser emitter 210 is placed near one of the wafers 10. Preferably, each laser emitter 210 is placed below the wafer 10 on a corresponding wafer placement position 110, and the longitudinal spacing between the light beam 220 emitted by each laser emitter 210 and the corresponding wafer 10 (i.e., the spacing along the axial direction of the support portion 120) is less than 5 mm. This also allows the emission sensing device to accurately monitor the position change of the wafer when the robot arm 300 takes and places the wafer 10, reduce the impact of other factors on the data, and avoid monitoring errors. Furthermore, the distance between the light beam 220 emitted by each laser emitter 210 and the wafer 10 above it is less than 3 mm.

[0043] In this embodiment, each laser emitter 210 and the corresponding laser sensor 230 are disposed in the axial through-slot of the carrier portion 120 and aligned with a wafer placement position 110. The number of laser emitters 210 can be 5, 10, 15, 20, 25, or any other number.

[0044] The processing system 400 includes a data processing module 410, which is used to generate a data graph in real time based on the electrical signal, such as a curve of the electrical signal changing with time, and to monitor whether the conveying device has abnormal conveying conditions such as position deviation of the robot arm 300, wafer 10 picking, wafer 10 sticking, etc. during the conveying process of the wafer 10 based on the curve of the electrical signal changing with time, and to issue an early warning when an abnormal conveying condition occurs, and can also control the wafer 10 to stop conveying at the same time as issuing an early warning.

[0045] The wafer transfer monitoring system further includes an alarm device 500 , which is connected to the processing system 400 and issues an alarm based on the early warning to notify the on-duty engineer to come for maintenance as soon as possible.

[0046] Please continue reading Figure 1 This embodiment further provides a wafer transfer monitoring method, which uses the wafer transfer monitoring system and includes the following steps:

[0047] Step S1: When the conveyor device is transferring wafers 10, the transmitting and sensing device generates a light beam 220 parallel to the wafer 10 near each wafer 10. The transmitting and sensing device outputs an electrical signal to the processing system 400 in real time based on the transmission status of the light beam 220 under the interference of the conveyor device.

[0048] Step S2: The processing system 400 monitors whether the wafer 10 is being transported normally according to the electrical signal, and issues an alarm if an abnormality occurs.

[0049] In step S1, when the wafer carrier 100 is a wafer loading device, the conveying device is a double-arm wafer conveyor, and the conveying device takes the wafer 10 out of the wafer loading device, or places the wafer 10 in the wafer vacuum loading chamber; when the wafer carrier 100 is a wafer vacuum loading chamber, the conveying device is a vacuum wafer conveyor, and the conveying device takes the wafer 10 out of the wafer vacuum loading chamber.

[0050] Step S1 is as follows: when the conveying device takes each wafer 10 out from the corresponding wafer placement position 110, since the wafer 10 is placed on the corresponding wafer placement position 110 of the wafer carrier 100, and each wafer 10 has a light beam 220 parallel to it near (for example, below), when the robot arm 300 of the conveying device approaches the wafer 10 from below the wafer 10 to be taken, the robot arm 300 does not contact the light beam 220 below the wafer 10, and the transmission of the light beam 220 is not blocked during this process. At the same time, the transmitting sensing device outputs a corresponding electrical signal in real time according to the reception status of the light beam 220; when the robot arm 300 When the robot arm 300 approaches the wafer 10 further, the robot arm 300 first contacts the light beam 220, and when the robot arm 300 moves upward to lift the wafer 10, the robot arm 300 blocks the light beam 220. During this process, the transmission of the light beam 220 is blocked, and the transmitting sensing device outputs a corresponding electrical signal according to the reception status of the light beam 220. In the process of the robot arm 300 moving further upward and taking out the wafer 10 from the wafer carrier 100, since the robot arm 300 is away from the light beam 220, that is, the robot arm 300 is not in contact with the light beam 220, the transmission of the light beam 220 is not blocked, and the transmitting sensing device outputs a corresponding electrical signal in real time according to the reception status of the light beam 220.

[0051] When the conveying device places the wafer 10 in the wafer carrier 100, the robotic arm 300 of the conveying device holds a wafer 10 to be placed and extends into the wafer carrier 100, and gradually approaches the wafer placement position 110 from above the wafer placement position 110 where the wafer 10 needs to be placed, and contacts the corresponding light beam 220. At this time, the transmission of the light beam 220 is not blocked, and the transmitting sensing device outputs a corresponding electrical signal in real time according to the reception situation of the light beam 220; the robotic arm 300 continues to move downward and places the wafer 10, and the robotic arm 300 blocks the light beam 220. At this time, the transmission of the light beam 220 is blocked, and the transmitting sensing device outputs a corresponding electrical signal according to the reception situation of the light beam 220; the robotic arm 300 continues to move downward and leaves the wafer carrier 100, and the robotic arm 300 is not in contact with the light beam 220. At this time, the transmission of the light beam 220 is not blocked, and the transmitting sensing device outputs a corresponding electrical signal in real time according to the reception situation of the light beam.

[0052] In step S2, the data processing module 410 of the processing system 400 generates a data graph in real time based on the electrical signal, such as a curve of the electrical signal changing over time, and uses the data graph when the position of the robot arm 300 is normal as a reference to compare the generated data graph with it. If there is no abnormality in the generated data graph, that is, the processing system 400 does not interfere with the transmission of the wafer 10. If there is an abnormality in the generated data graph, the processing system 400 promptly issues an early warning and can control the wafer 10 to stop transmitting. In other embodiments, if there is an abnormality in the generated data graph, the processing system 400 promptly issues an early warning and the on-site maintenance engineer controls the wafer 10 to stop transmitting.

[0053] The following description will be made by taking as an example that the conveying device is a vacuum wafer conveyor, the wafer carrier 100 is a wafer vacuum loading chamber, and the conveying device takes the wafer 10 out of the wafer carrier 100 .

[0054] First, the robotic arm 300 extends into the wafer carrier 100 and is located below the wafer 10 that needs to be taken out, and gradually approaches the corresponding light beam 220 until the robotic arm 300 contacts the light beam 220. During this process, the laser sensor 230 below the wafer 10 that needs to be taken out (that is, the corresponding laser sensor 230) can receive the light beam 220 emitted by the laser emitter 210. At the same time, all laser sensors 230 receive the light beam 220 emitted by the laser emitter 210, and the corresponding laser emitter 210 outputs the corresponding electrical signal to the data processing module 410 in real time according to the reception status of the light beam 220. Next, the robotic arm 300 moves upward and lifts the wafer 10. The robotic arm 300 blocks the light beam 220. During this process, the corresponding laser sensor 230 cannot receive the light beam 220 emitted by the laser emitter 210. The other laser sensors 230 all receive the light beam 220 emitted by the laser emitter 210. The corresponding laser emitter 210 outputs a corresponding electrical signal to the data processing module 410 in real time based on the reception of the light beam 220. Next, the robotic arm 300 continues to lift the wafer 10 upward so that the robotic arm 300 is not in contact with the light beam 220. The robotic arm 300 further moves away from the wafer carrier 100. During this process, the corresponding laser sensor 230 can receive the light beam 220. At the same time, all laser sensors 230 receive the light beam 220 emitted by the laser emitter 210. The corresponding laser emitter 210 outputs a corresponding electrical signal to the data processing module 410 in real time based on the reception of the light beam 220.

[0055] exist Figure 3In a, with the normal position of the robot arm 300 as a reference, before the robot arm 300 approaches the wafer 10 and contacts the light beam 220 (i.e., time period 0 to A), since the corresponding laser sensor 230 can receive the light beam 220 emitted by the laser emitter 210, the processing system 400 draws the data diagram based on the electrical signal provided by the corresponding laser sensor 230, and the electrical signal outputs a high level in the time period 0 to A; during the process of the robot arm 300 blocking the light beam 220 (i.e., time period A to B), since the corresponding laser sensor 230 does not receive the light beam 220 emitted by the laser emitter 210, the processing system 400 outputs a high level in the data diagram based on the electrical signal provided by the corresponding laser sensor 230. In the data graph drawn by the processing system 400 based on the electrical signal provided by the laser sensor 230, the electrical signal outputs a low level, and at time point A, the electrical signal changes from a high level to a low level; in the process of the robotic arm 300 moving away from the beam 220 (the time is greater than the time period B), since the corresponding laser sensor 230 can receive the beam 220 emitted by the laser emitter 210, the electrical signal outputs a high level in the data graph drawn by the processing system 400 based on the electrical signal provided by the laser sensor 230, that is, at time point B, the electrical signal changes from ground frequency to high level.

[0056] exist Figure 3In figure b, the position of the robot arm 300 is tilted (that is, the side surface of the robot arm 300 facing the wafer 10 is not parallel to the surface of the wafer 10 to be taken out), and the tilt is slight. At this time, when the robot arm 300 gradually approaches the light beam 220 under the wafer 10 to be taken out, the robot arm 300 will contact the light beam 220 in advance, that is, the robot arm 300 will contact the light beam 220 between time points A, that is, the time before contact is shortened and the high level maintenance time is shortened, and the time when the robot arm 300 lifts the wafer 10 to block the light beam 220 will also be advanced, that is, the total time of blocking the light beam 220 has not changed, but the start time and end time of the blocking are advanced. Similarly, the time when the robot arm 300 is away from the light beam 220 is advanced, that is, the time when the electrical signal changes from high level to low level is earlier than A, and the time when the electrical signal changes from low level to high level is earlier than B. During this process, due to the tilted position of the robotic arm 300, the raised side of the wafer 10 when being lifted can easily touch the wafer 10 or the wafer placement position 110 above the wafer 10 to be removed, which can easily cause scratches or even damage to the wafer 10. The data processing system 400 draws a data graph based on the electrical signal and compares the data graph with the data graph when the robot arm 300 is in a normal position; or finds the electrical signal change time points A and B from the data graph when the robot arm 300 is in a normal position, and compares the level change time points in the data graph with them, so as to obtain abnormal data (for example, when compared with the electrical signal change time point A, the level change time point in the data graph is less than 85% of the electrical signal change time point A, or greater than 115% of the electrical signal change time point A; when compared with the electrical signal change time point B, the level change time point in the data graph is less than 85% of the electrical signal change time point B, or greater than 115% of the electrical signal change time point B), that is, the processing system 400 monitors the abnormal transmission of the wafer 10. At this time, the processing system 400 performs alarm processing through the alarm device to prompt the on-site maintenance engineer to arrive in time for processing, and at the same time control the machine to stop the transmission of the wafer 10.

[0057] In addition, due to the real-time output of the electrical signal, the processing system 400 also draws the data graph in real time. In this way, when the electrical level changes before time point A, the processing system 400 will detect it in real time and respond in time, thereby preventing the wafer 10 from being scratched or damaged, so that the abnormality can be handled in time, and equipment with potential risks can be handled. It also increases the success rate of wafer 10 transmission, while avoiding machine downtime caused by abnormalities, improving the normal operation time of the machine, and ensuring the quality of the wafer 10, delaying the stable production time of the machine, and reducing the workload of the on-duty engineer.

[0058] Similarly, in Figure 3In c, the position of the robot arm 300 is upward, that is, closer to the wafer 10 than the normal position. In this way, the robot arm 300 may have contacted the light beam 220 when it was inserted into the wafer carrier 100, so that it has started to contact the light beam 220 before time point A, or even at time point 0. This will cause the electrical signal to change from a high level to a low level in advance, and the level will change again at time B. At this time, since the level changes to a low level in advance before time point A, the data processing system 400 promptly discovers this abnormality based on the data graph drawn by the electrical signal and takes the following measures: Figure 3 The same action as in step b (control shutdown and alarm) is performed.

[0059] exist Figure 3 In d, the position of the robot arm 300 is lower, and the robot arm 300 will delay contacting the light beam 220, that is, contacting the light beam 220 after time point A and starting to block the light beam 220. In this way, the entire blocking time remains unchanged, the time when the electrical signal changes from high level to low level is later than time point A, and the time when the electrical signal changes from low level to high level is later than time point B. The processing system 400 will discover the impending risk in time at time point A. Therefore, at this time, the following measures can also be taken Figure 3 The same action as in step b (control shutdown and alarm) is performed.

[0060] In addition, the data graph of abnormal occurrence of wafer 10 adjustment or wafer 10 sticking is similar to Figure 3 That is, after time point A, the light beam 220 is contacted and begins to be blocked. In this way, the entire blocking time remains unchanged, the time when the electrical signal changes from high level to low level is later than time point A, and the time when the electrical signal changes from low level to high level is later than time point B. The processing system 400 will discover the impending risk in time at time point A. Therefore, at this time, the following measures can also be taken: Figure 3 The same action as in step b (control shutdown and alarm) is performed.

[0061] In summary, the present invention provides a wafer transmission monitoring system and a wafer transmission monitoring method. The wafer transmission monitoring system includes a wafer carrying device, an emitting sensing device, a transmission device and a processing system. The wafer carrying device is used to carry multiple wafers, and the transmission device is used to take and deliver the wafers in the wafer carrying device. The emitting sensing device is arranged on the wafer carrying device and can generate a light beam parallel to the wafer near each wafer. The emitting sensing device is connected to the processing system and is used to output an electrical signal to the processing system in real time according to the transmission status of the light beam under the interference of the transmission device. The processing system is used to monitor whether the transmission of the wafer is normal according to the electrical signal and to issue an alarm in case of an abnormality. It can monitor in real time the risk of wafer scratches or even wafer breakage caused by abnormalities in the wafer transmission process, can prevent potential risks, and also increase the success rate of wafer transmission. It can timely alarm when the transmission is abnormal and stop the wafer transmission action, avoiding the risk of wafer scrapping caused by abnormalities in the transmission device, improving the normal operation time of the machine, while also ensuring the quality of the wafer, delaying the stable production time of the machine, and reducing the workload of the on-duty engineer.

[0062] In addition, it should be noted that, unless otherwise specified or indicated, the terms "first" and "second" in the specification are only used to distinguish the various components, elements, steps, etc. in the specification, and are not used to indicate the logical relationship or sequential relationship between the various components, elements, steps, etc.

[0063] It is understood that although the present invention has been disclosed above with reference to preferred embodiments, the above embodiments are not intended to limit the present invention. For any person skilled in the art, without departing from the scope of the technical solution of the present invention, the technical content disclosed above can be used to make many possible changes and modifications to the technical solution of the present invention, or to modify it into an equivalent embodiment with equivalent changes. Therefore, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A wafer transfer monitoring system, characterized in that: It includes a wafer carrying device, an emitting sensing device, a conveying device and a processing system. The wafer carrying device is used to carry multiple wafers, and the conveying device is used to take and deliver the wafers in the wafer carrying device. The emitting sensing device is arranged on the wafer carrying device and can generate a light beam parallel to the wafer near each wafer. The emitting sensing device is connected to the processing system and is used to output an electrical signal to the processing system in real time according to the transmission status of the light beam under the interference of the conveying device. The processing system is used to monitor whether the transmission of the wafer is normal based on the electrical signal and to issue an alarm in case of abnormality.

2. The wafer transfer monitoring system according to claim 1, wherein: The emitting and sensing device includes multiple laser emitters and multiple laser sensors. Each of the laser emitters is arranged opposite to a laser sensor, so that each of the laser emitters can emit a light beam, and each of the laser sensors can receive the light beam emitted by the corresponding laser emitter. During the process of taking or placing the wafer, the device outputs an electrical signal to the processing system in real time based on the reception status of the light beam caused by the position change between the conveying device and the light beam.

3. The wafer transfer monitoring system according to claim 2, wherein: The wafer carrying device includes a plurality of wafer placement positions, all of which are arranged in sequence from bottom to top at fixed intervals, and each of the wafer placement positions can hold a wafer; Each of the laser emitters is placed below the wafer on a corresponding wafer placement position, and a longitudinal distance between a light beam emitted by each of the laser emitters and the corresponding wafer is less than 5 mm.

4. The wafer transfer monitoring system according to claim 2, wherein: The number of the laser emitters is the same as the number of the laser sensors and the number of the wafer placement positions.

5. The wafer transfer monitoring system according to claim 1, wherein: The diameter of the light beam is within 1 mm, and the transmission speed of the electrical signal is at or below the millisecond level.

6. The wafer transfer monitoring system according to claim 1, wherein: The processing system includes a data processing module, which is used to generate a data graph in real time according to the electrical signal, and to monitor whether the conveying device is normal during the wafer conveying process according to the data graph, and to issue an early warning in case of abnormality, and can also control the wafer to stop transmission while issuing an early warning.

7. A wafer transfer monitoring method, using the wafer transfer monitoring system according to claim 1, characterized in that: The following steps are involved: When the conveyor device takes or delivers wafers from the wafer carrier device, the transmitting and sensing device generates a light beam parallel to each wafer near the wafer, and the transmitting and sensing device outputs an electrical signal to the processing system in real time according to the transmission status of the light beam under the interference of the conveyor device; The processing system monitors whether the wafer transfer is normal according to the electrical signal and issues an alarm when an abnormality occurs.

8. The wafer transfer monitoring method according to claim 7, wherein: The specific steps for the conveyor to remove the wafer are: The robotic arm of the conveying device extends into the wafer carrying device and approaches the wafer from below the wafer to be taken, and contacts the corresponding light beam. At this time, the transmission of the light beam is not blocked, and the transmitting sensing device outputs an electrical signal in real time according to the reception status of the light beam; The robotic arm continues to approach the wafer and lifts the wafer, and the robotic arm blocks the light beam. At this time, the transmission of the light beam is blocked, and the transmitting sensing device outputs an electrical signal according to the reception status of the light beam. The robotic arm continues to move upward and takes out the wafer from the wafer carrying device. The robotic arm does not contact the light beam. At this time, the transmission of the light beam is not blocked. At the same time, the transmitting sensing device outputs an electrical signal in real time according to the light beam reception situation.

9. The wafer transfer monitoring method according to claim 7, wherein: The wafer carrying device includes a plurality of wafer placement positions, all of which are arranged in sequence from bottom to top at fixed intervals, and each of the wafer placement positions can hold a wafer. At the same time, the specific steps of placing the wafer by the conveying device are as follows: The robotic arm of the conveying device holds a wafer to be placed and extends into the wafer carrying device, and gradually approaches the wafer placement position where the wafer is to be placed from above the wafer placement position, and contacts the corresponding light beam. At this time, the transmission of the light beam is not blocked, and the transmitting sensing device outputs an electrical signal in real time according to the reception status of the light beam; The robotic arm continues to move downward and places the wafer, and the robotic arm blocks the light beam. At this time, the transmission of the light beam is blocked, and at the same time, the transmitting sensing device outputs an electrical signal according to the light beam reception situation; The robotic arm continues to move downward and leaves the wafer carrier, and the robotic arm is not in contact with the light beam. At this time, the light beam transmission is not blocked, and the transmitting sensing device outputs an electrical signal in real time according to the light beam reception situation.

10. The wafer transfer monitoring method according to claim 8 or 9, wherein: The specific steps of the processing system monitoring whether the wafer transfer is normal according to the electrical signal are as follows: The data processing module of the processing system generates a data graph in real time according to the electrical signal, and compares the generated data graph with the data graph when the robot arm is in a normal position as a reference. When the generated data graph is abnormal, the processing system issues an early warning in time and controls the wafer to stop transmission.

Images