Substrate conveying system and method for monitoring conveying deviation of substrate conveying system

Abstract

The invention provides a substrate conveying system and a method for monitoring conveying deviation of the substrate conveying system. In the monitoring method, the deviation state of the substrate is obtained by detecting the substrate from the transmission equipment, so that the transmission deviation of the transmission system is reflected according to the deviation state of the substrate, automatic monitoring of the transmission system is realized, the monitoring efficiency is improved, transmission abnormity can be monitored in time, feedback processing is carried out, and the monitoring accuracy is improved. And the problem of large-scale scrapping or yield reduction caused by the fact that the transmission abnormity is not found in time is reduced.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a substrate conveying system and a method for monitoring conveying deviation thereof. Background Art

[0002] In the field of semiconductor processing, a series of transmission equipment is usually required to transmit the substrate to be processed to various processing equipment for the corresponding processing steps. Therefore, in order to achieve high processing accuracy of the processing equipment for the substrate placed therein, one of the important links is to ensure that the substrate is accurately placed in the processing equipment, which requires that each transmission equipment on the substrate transmission path meet the transmission accuracy requirements. In particular, for the production equipment of nano-scale integrated circuits, there are extremely high requirements for transmission deviation and repeatability.

[0003] However, since the stability of the hardware cannot be guaranteed, the equipment needs to be regularly pre-maintained (PM) to avoid product scratches or scrapping due to hardware failure, usually once a month. Due to the long time, timeliness cannot be guaranteed, so when problems with the transmission equipment are discovered, hundreds or thousands of wafers have been affected, resulting in huge losses; in addition, increasing the frequency of downtime inspections will greatly affect the utilization rate of semiconductor equipment and the productivity of products. Summary of the invention

[0004] The object of the present invention is to provide a method for monitoring the transmission deviation of a transmission system, so as to realize a real-time and efficient monitoring process of the transmission system.

[0005] In this regard, the present invention provides a method for monitoring the transmission deviation of a transmission system, comprising: utilizing at least one transmission device to transmit a substrate, including transmitting the substrate to a detection platform of a detection device to detect an actual position of the substrate on the detection platform; and obtaining an offset state of the substrate according to the actual position and theoretical position of the substrate, and judging the transmission deviation of the transmission device along the transmission path of the substrate according to the offset state of the substrate.

[0006] Optionally, the method for obtaining the offset state of the substrate includes: using the image sensor of the detection device to identify at least one measurement mark on the substrate, and when identifying the measurement mark, the center of the camera field of view of the image sensor is opposite to the theoretical position of the measurement mark, so as to obtain the offset state of the actual position of the measurement mark relative to the center of the camera field of view, and obtain the offset state of the actual position and theoretical position of the substrate.

[0007] Optionally, a control interval is also set based on the camera field of view of the image sensor, the center of the control interval coincides with the center of the camera field of view and is located within the range of the camera field of view, and is used to generate warning information when the identified measurement mark exceeds the control interval.

[0008] Optionally, the control area covers 2 / 3 of the camera field of view.

[0009] Optionally, the camera field of view is a rectangle, and the control interval has two first control lines opposite to each other in a first direction and two second control lines opposite to each other in a second direction, and the two first control lines and the two second control lines surround a rectangular control interval.

[0010] Optionally, the monitoring method further comprises: recording the offset detection results of the detection device on multiple substrates, and generating a warning message when the offset values ​​of multiple detection results gradually increase for a predetermined number of consecutive times on the same side of the center line.

[0011] Optionally, a measurement mark is set at the center point of the substrate. When identifying the measurement mark at the center point of the substrate, the camera field of view of the image sensor is facing the center of the detection platform to obtain the offset state of the center point of the substrate relative to the center point of the camera field of view in the substrate image.

[0012] Optionally, the detection device determines the offset state of the actual coordinate system of the substrate relative to the theoretical coordinate system by acquiring a coordinate system with the center of the substrate as the origin.

[0013] Optionally, at least two measurement marks are set on the substrate, and the actual position of each measurement mark is obtained by identifying the at least two measurement marks, and the actual position of each identified measurement mark is matched with the theoretical position one by one to obtain the offset state of the substrate.

[0014] Optionally, the offset state of the substrate includes a translation amount of the substrate in a two-dimensional direction; and / or a deflection angle of the substrate.

[0015] Optionally, at least two measurement marks are set on the substrate, and the actual positions of the at least two measurement marks are identified, and the translation amount of the substrate in the first direction and the second direction, and the deflection angle of the substrate are obtained according to the following formula;

[0016] X A '=X A *cosθ-Y A *sinθ+△X

[0017] Y A '=X A *sinθ+Y A *cosθ+△Y

[0018] X B '=X B *cosθ-Y B *sinθ+△X

[0019] Y B '=X B *sinθ+Y B *cosθ+△Y

[0020] Among them, X A is the theoretical value of the first measurement mark in the X direction;

[0021] X B is the theoretical value of the second measurement mark in the X direction;

[0022] Y A is the theoretical value of the first measurement mark in the Y direction;

[0023] Y B is the theoretical value of the second measurement mark in the Y direction;

[0024] X A ' is the actual value of the first measurement mark in the X direction;

[0025] X B ' is the actual value of the second measurement mark in the X direction;

[0026] Y A ' is the actual value of the first measurement mark in the Y direction;

[0027] Y B ' is the actual value of the second measurement mark in the Y direction;

[0028] △X is the translation of the substrate in the X direction;

[0029] △Y is the translation of the substrate in the Y direction;

[0030] θ is the deflection angle of the substrate.

[0031] The present invention also provides a substrate conveying system, comprising: at least one conveying device for conveying the substrate; a detection device, arranged on the conveying path of the conveying system, for receiving the substrate transmitted from the conveying device and detecting the actual position of the substrate on the detection platform; and a data processing unit, for performing data processing on the actual position and theoretical position of the substrate to obtain the offset state of the substrate, and judging the conveying deviation of the conveying device along the conveying path of the substrate according to the offset state of the substrate.

[0032] Optionally, the detection device includes an image sensor for identifying at least one measurement mark on the substrate, and when identifying the measurement mark, the center of the camera field of view of the image sensor is aligned with the theoretical position of the measurement mark to obtain the offset state of the actual position of the measurement mark relative to the center of the camera field of view, and obtain the offset state of the actual position and theoretical position of the substrate.

[0033] Optionally, the data processing unit is also used to generate a warning message when the identified measurement mark exceeds a control interval, wherein the control interval is set based on the camera field of view of the image sensor, and the center of the control interval coincides with the center of the camera field of view and is within the range of the camera field of view.

[0034] Optionally, the data processing unit is further used to record the offset detection results of the detection equipment on multiple substrates, and when the offset values ​​of multiple detection results gradually increase for a predetermined number of consecutive times on the same side of the center line, an early warning message is generated.

[0035] Optionally, the conveying system further comprises a pre-alignment mechanism for pre-aligning the substrate, including adjusting the deflection direction of the substrate to a predetermined direction.

[0036] In the method for monitoring the transmission deviation of the transmission system provided by the present invention, a detection device is set in the transmission path of the substrate, and the detection device is used to detect the substrate from the transmission device to obtain the offset state of the substrate, so that the transmission deviation of the transmission system can be reflected according to the offset state of the substrate. The monitoring method can realize automatic monitoring of the transmission system, without the need to perform precision detection on a series of transmission devices in the transmission system one by one, effectively improving the monitoring efficiency, facilitating timely monitoring of transmission anomalies and feedback processing, and reducing the problem of large-scale scrapping or yield reduction caused by failure to timely discover transmission anomalies. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the structure of a transmission system in one embodiment of the present invention.

[0038] Figure 2 The figure is an example of the imaging field of view of the image sensor of the detection device in one embodiment of the present invention and an image of a substrate captured thereby.

[0039] Figure 3 The image sensor's field of view and the set control range of the detection device in one embodiment of the present invention.

[0040] Figure 4 It is a result of position deviation of a substrate in the X direction collected during the monitoring of a conveying system in one embodiment of the present invention.

[0041] Figure 5 It is a result of position deviation of a substrate in the Y direction collected during the monitoring of a conveying system in one embodiment of the present invention.

[0042] Figure 6 and Figure 7 It is a structural schematic diagram when the actual position of the substrate is offset relative to the theoretical position.

[0043] Figure 8-Figure 9 A schematic diagram to assist in deriving the formula for calculating the translation and deflection angle of the substrate.

[0044] The reference numerals are as follows:

[0045] 110-transmission equipment;

[0046] 120-Detection equipment;

[0047] 121-Detection platform;

[0048] 122- Image sensor;

[0049] 130-pre-alignment mechanism;

[0050] 200-Substrate. DETAILED DESCRIPTION

[0051] The core concept of the present invention is to provide a method for monitoring the transmission deviation of a transmission system, which specifically includes: utilizing at least one transmission device in the transmission system to transmit a substrate, including transmitting the substrate to a detection platform of a detection device to detect the actual position of the substrate on the detection platform; and obtaining the offset state of the substrate according to the actual position and theoretical position of the substrate, so as to judge the transmission deviation of the transmission device along the transmission path of the substrate according to the offset state of the substrate.

[0052] That is, in the method for monitoring the transmission deviation of the transmission system provided by the present invention, a detection device is arranged in the transmission path of the substrate, so that the substrate can be further transmitted to the detection device after passing through at least a part of the transmission device, so that the offset state of the substrate can be detected by the detection device, thereby reflecting the overall transmission deviation of the transmission device located before the detection device on the transmission path.

[0053] The following is a further detailed description of the substrate conveying system and the method for monitoring its conveying deviation proposed by the present invention in conjunction with specific embodiments. According to the following description, the advantages and features of the present invention will become clearer. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. It should be recognized that relative terms such as "above", "below", "top", "bottom", "above" and "below" shown in the drawings can be used to describe the relationship between various elements. These relative terms are intended to cover different orientations of elements other than the orientations depicted in the drawings. For example, if the device is inverted relative to the view in the drawing, an element described as being "above" another element will now be below the element.

[0054] Figure 1 is a schematic diagram of the structure of a transmission system in one embodiment of the present invention, Figure 1 Only one transmission system is shown as an example. Figure 1 The transmission system shown in the figure is used as an example to explain the method of monitoring its transmission deviation. Figure 1 As shown, the conveying system includes at least one conveying device 110, and the specific conveying device 110 is, for example, a conveying arm, which is used to convey the substrate 200 to a predetermined position (for example, it can be used to convey the substrate 200 to a predetermined processing equipment or testing equipment, etc.).

[0055] Furthermore, the conveying system also includes a detection device 120. The substrate 200 can be conveyed to the detection platform 121 of the detection device 120 via one or more transmission devices 110. The detection device 120 is used to detect the substrate 200 to obtain the offset state of the substrate 200 on the detection platform 121 relative to the theoretical position, so that the transmission deviation of the transmission device 110 along the transmission path of the substrate can be judged according to the offset state of the substrate 200.

[0056] Specifically, when it is detected that the substrate 200 has no offset or only a slight offset and the offset is still within the specification range, it can be reflected that the transmission deviation of each transmission device 110 on the transmission path meets the requirements, and the overall transmission accuracy of the transmission system is high, so it can be ensured that the substrate 200 is finally accurately transmitted to the detection platform 121. On the contrary, when it is detected that the substrate 200 has an offset and the offset exceeds the specification range, it is reflected that the transmission deviation of at least part of the transmission devices 110 on the transmission path exceeds the allowable deviation range, and the overall transmission accuracy of the transmission system is low, resulting in a large degree of deviation when the substrate 200 is finally transmitted to the detection platform 121.

[0057] In practical applications, a threshold range of the substrate offset value can be set. When the substrate offset value exceeds the threshold range, it indicates that the current transmission system has a large error, and a warning signal can be generated to prompt the transmission system to be checked and corrected; conversely, when the substrate offset value does not exceed the threshold range, it indicates that the transmission deviation of the current transmission system meets the requirements, allowing the transmission system to continue to operate. The threshold range of the substrate offset value can be set according to specific equipment, specific usage scenarios, etc., and is not limited here.

[0058] Continue to refer Figure 1 As shown, the detection device 120 in this embodiment has an image sensor 122 , so as to utilize the image sensor 122 to obtain an image of a substrate located on a detection platform 121 , and then determine the offset state of the substrate 200 .

[0059] Specifically, at least one measurement mark may be set on the substrate 200. When the substrate 200 is inspected, the measurement mark is identified by the image sensor 122, so that the actual position of the substrate 200 is reflected according to the actual position of the measurement mark. When identifying each measurement mark, the center of the camera field of view FOV of the image sensor 122 may be further aligned with the theoretical position of the measurement mark currently required to be measured. In this way, the position of the measurement mark in the acquired substrate image may be compared with the center position of the camera field of view FOV to obtain the offset state of the measurement mark in the substrate image relative to the center of the camera field of view FOV. That is, before inspecting the substrate 200, a detection program may be set in the inspection device 120 in priority. The detection program may locate the theoretical position of each measurement mark, and when inspecting, the image sensor 122 may be controlled so that the center of the camera field of view FOV may be aligned with the theoretical position of the measurement mark currently required to be measured.

[0060] In one example, a measurement mark may be set at the center point of the substrate 200. Since the center point of the substrate 200 theoretically coincides with the center point of the detection platform 121, the theoretical position corresponding to the measurement mark at the center position of the substrate coincides with the center point of the detection platform 121. When identifying the measurement mark at the center point of the substrate 200, the image sensor 122 may be positioned directly above the center of the detection platform 121 so that the camera field of view FOV of the image sensor 122 is directly facing the center of the detection platform 121 (i.e., the center of the camera field of view FOV coincides with the center height of the detection platform 121). Based on this, the center point of the substrate 200 may be identified when capturing the substrate image, and the offset state of the center point of the substrate relative to the center point of the camera field of view FOV in the acquired substrate image may be compared to obtain the offset state of the substrate. For example, reference may be made to Figure 2, which illustrates an example of a substrate image captured by the image sensor 122 and the imaging field of view FOV. In this example, it can be seen from the captured substrate image that the center point of the substrate is offset in the upper left direction relative to the center point of the imaging field of view FOV, thereby reflecting the offset state of the substrate 200.

[0061] In a further solution, a control interval can be set based on the camera field of view FOV, and a warning message is generated when the identified measurement mark exceeds the control interval. The center of the control interval coincides with the center of the camera field of view FOV and is located within the area of ​​the camera field of view FOV. For example, the control interval covers about 2 / 3 of the camera field of view FOV.

[0062] For example, reference Figure 3 As shown, the camera field of view FOV is a rectangle, and the control interval has a first control line UCL_X / LCL_X opposite to each other in the first direction (X direction) and a second control line UCL_Y / LCL_Y opposite to each other in the second direction (Y direction). The two first control lines and the two second control lines surround a rectangular control interval, that is, the two first control lines are equidistantly located on both sides of the center line of the camera field of view FOV, and the two second control lines are equidistantly located on both sides of the center line of the camera field of view FOV. For example, combined with Figure 4 and Figure 5 As shown, when the measurement mark in the camera field of view FOV is located within the control interval in both the X direction and the Y direction, the detection device 120 can continue the current measurement process; on the contrary, when the measurement mark in the camera field of view FOV exceeds the control interval in any direction (for example, Figure 4 The measurement mark represented by the solid square exceeds the control line in the X direction; Figure 5 If the measurement mark represented by the solid square exceeds the control line in the Y direction, it means that the transmission error of the substrate 200 is large. At this time, an early warning message can be directly generated to prompt the transmission system to be checked and corrected.

[0063] In a specific example, the offset detection results of the detection device 120 for multiple substrates can be continuously tracked and recorded, which can not only monitor the transmission deviation of the transmission system in real time, but also help to judge the equipment stability of the transmission system. As described above, when the identified measurement mark exceeds the control interval, a warning message can be generated; or, in the tracked offset detection results, when the offset values ​​of multiple detection results are found to be gradually increasing for a predetermined number of times on the same side of the center line, a warning message can also be generated. For example, in the continuously tracked offset detection results, if it is found that the offset value is offset in the positive direction of the X-axis for seven consecutive times and the offset increases successively; or, the offset value is offset in the negative direction of the X-axis for seven consecutive times and the offset increases successively; or, the offset value is offset in the positive direction of the Y-axis for seven consecutive times and the offset increases successively; or, the offset value is offset in the negative direction of the Y-axis for seven consecutive times and the offset increases successively, a warning message can be generated when any of them is met to prompt the transmission system to be checked and corrected.

[0064] In addition, it is mentioned above that a threshold range can be set for the offset value of the substrate, and the threshold range can, for example, represent the maximum transmission deviation allowed by the transmission system. In this embodiment, the control interval set for the camera field of view FOV can be smaller than the threshold range of the offset value of the substrate, so that the transmission deviation of the device can be discovered earlier under the monitoring of the control interval. Therefore, in practical applications, there is no need to set an additional threshold range for the offset value of the substrate.

[0065] The above example describes in detail that a measurement mark is set at the center of the substrate 200 to determine the offset state according to the center position of the substrate 200. In other examples, the measurement mark can be set at any position of the substrate 200, and the measurement mark can be set at one or more positions. Figure 6 As shown, at least two measurement marks may be set on the substrate 200, and corresponding position information is obtained by identifying at least two measurement marks, and data processing is performed on the actual position and theoretical position of each identified measurement mark, for example Figure 6 The actual position A' of the first measurement mark is aligned with the theoretical position A, and the actual position B' of the second measurement mark is aligned with the theoretical position B, thereby obtaining the offset state of the substrate.

[0066] It should be noted that by setting at least two measurement marks on the substrate, not only the translation direction and translation amount of the substrate 200 on the two-dimensional plane can be obtained according to the alignment matching result, but also the deflection angle of the substrate 200 can be obtained. Figure 6According to the actual position A' and the theoretical position A of the first measurement mark, and the actual position B' and the theoretical position B of the second measurement mark, it can be obtained that the actual position of the substrate 200 relative to the theoretical position not only has a translation along the first direction and the second direction, but also has a clockwise deflection.

[0067] Continue to refer Figure 1 As shown, the conveying system further includes a pre-aligner 130, such as a flat edger, for pre-aligning the substrate 200 (for example, for pre-aligning the deflection direction of the substrate 200) to reduce the error of the conveying process. In a specific example, the conveying system is used to convey wafers, and the edges of the wafers are usually provided with notches (for example, Figure 2 As shown), the notch is used to indicate the direction of the wafer; wherein, after the wafer is placed on the pre-alignment mechanism 130, the pre-alignment mechanism 130 can position the notch on the edge of the wafer and rotate the notch on the edge of the wafer to a predetermined direction, so that the deflection direction of each wafer in the subsequent transmission path is consistent, so that it can be transmitted to the processing equipment or the detection equipment 120 in a predetermined direction.

[0068] In this embodiment, the substrate may be preferentially transferred to the pre-alignment mechanism 130, and then the substrate may be transferred to the detection device 120. On this basis, when the detection device 120 is used to measure the substrate 200, the offset direction of the substrate may be roughly determined directly according to the offset direction of the measurement mark. Of course, even if the pre-alignment mechanism 130 is provided in the transmission system, the detection device 120 may still be used to simultaneously detect the deflection angle and the translation amount on the two-dimensional plane of the substrate 200, so as to facilitate more accurate monitoring of the transmission deviation of the substrate.

[0069] It should be noted that, in practical applications, the offset state of the substrate can be directly determined based on the detection results of each measurement mark. Alternatively, the detection results of each measurement mark can be used to further obtain a coordinate system of the substrate with its center as the origin, and the offset state of the substrate can be obtained based on the offset state of the actual coordinate system of the substrate relative to the theoretical coordinate system. Specifically, at least two measurement marks on the substrate can be identified, and the actual position and theoretical position of each measurement mark can be matched one by one, thereby obtaining the offset state of the actual coordinate system of the substrate relative to the theoretical coordinate system. For example, refer to Figure 7 As shown, the offset state of the actual coordinate system (X'O'Y') of the substrate relative to the theoretical coordinate system (XOY) can be obtained according to the actual position A' and theoretical position A of the first measurement mark, and the actual position B' and theoretical position B of the second measurement mark.

[0070] It should be recognized that, according to the offset state of the actual coordinate system of the substrate relative to the theoretical coordinate system, it can also simultaneously reflect the translation direction and translation amount of the substrate 200 in the two-dimensional plane (for example, the translation amount in the X direction and the Y direction), and the deflection angle of the substrate 200 can also be obtained.

[0071] As described above, in this embodiment, by setting at least two measurement marks on the substrate, it can not only be used to determine whether the current offset condition of the substrate 200 meets the requirements, but also can further calculate the specific offset amount of the substrate 200, including the translation direction and translation amount of the substrate 200 on the two-dimensional plane, and the deflection angle of the substrate 200.

[0072] Specifically, the translation amount ΔX of the substrate 200 in the first direction (X direction), the translation amount ΔY in the second direction (Y direction), and the deflection angle θ of the substrate can be further calculated by the following equation group (including Formula 1-Formula 4).

[0073] X A '= X A *cosθ- Y A *sinθ+△X Formula 1

[0074] Y A '= X A *sinθ+ Y A *cosθ+△Y Formula 2

[0075] X B '= X B *cosθ- Y B *sinθ+△X Formula 3

[0076] Y B '= X B *sinθ+ Y B *cosθ+△Y Formula 4

[0077] Among them, X A is the theoretical value of the first measurement mark in the X direction;

[0078] X B is the theoretical value of the second measurement mark in the X direction;

[0079] Y A is the theoretical value of the first measurement mark in the Y direction;

[0080] Y B is the theoretical value of the second measurement mark in the Y direction;

[0081] X A ' is the actual value of the first measurement mark in the X direction;

[0082] X B ' is the actual value of the second measurement mark in the X direction;

[0083] Y A ' is the actual value of the first measurement mark in the Y direction;

[0084] Y B ' is the actual value of the second measurement mark in the Y direction;

[0085] △X is the translation of the substrate in the X direction;

[0086] △Y is the translation of the substrate in the Y direction;

[0087] θ is the deflection angle of the substrate.

[0088] Combine the following Figure 8-Figure 9 , the formulas in the equation group are derived and explained. In this derivation process, only the relationship between the actual position of one measurement mark and the theoretical position is derived and explained, and the derivation process of the relationship between the actual position of other measurement marks and the theoretical position is similar.

[0089] First reference Figure 8 As shown, assuming that the substrate is only deflected and its deflection angle is θ, the following formulas 5 to 8 can be obtained.

[0090] X=r*cosα Formula 5

[0091] Y=r*sinα Formula 6

[0092] X'=r*cos(α+θ) Formula 7

[0093] Y'=r*sin(α+θ) Formula 8

[0094] According to the equation group of Formula 5-Formula 8, the relationship between the actual position of the deflected measurement mark in the X direction and the theoretical position, and the relationship between the actual position in the Y direction and the theoretical position can be further obtained, as shown in the following Formula 9-Formula 10.

[0095] X'=r* cosαcosθ-r* sinαsinθ=X*cosθ-Y*sinθ Formula 9

[0096] Y'=r* cosαsinθ+r *sinαcosθ=X*sinθ+Y*cosθ Formula 10

[0097] Next reference Fig. 9As shown, when the substrate is deflected and the translation amount in the X direction is △X, and the translation amount in the Y direction is △Y, the following formula can be obtained.

[0098] X'=X*cosθ-Y*sinθ+ΔX Formula 11

[0099] Y'=X*sinθ+Y*cosθ+△Y Formula 12

[0100] Therefore, when two measurement marks are set on the substrate 200, the equation group of Formula 1 to Formula 4 can be obtained, so that the translation amount and deflection angle of the substrate can be calculated.

[0101] It should be recognized that when the image of the substrate is acquired by using the image sensor 122, when the actual position of the measurement mark in the substrate image is greatly offset relative to the center position of the camera field of view FOV, it may be caused only by the translation of the substrate on the two-dimensional plane, or it may be caused by the deflection of the substrate, or it may be caused by the translation and deflection of the substrate at the same time. In other words, when the substrate deflects, the measurement mark in the camera field of view FOV is manifested as a translation in the two-dimensional direction (that is, the translation in the X direction and the Y direction). When the measurement mark exceeds the control range of the camera field of view FOV, it means that at least one of the deflection angle, the X-direction translation amount and the Y-direction translation amount of the substrate is offset.

[0102] In summary, the method for monitoring the transmission deviation of the transmission system provided in this embodiment specifically uses the offset state of the substrate being transmitted to reflect whether the transmission deviation meets the requirements. When the detection result of the offset state of the substrate is abnormal, an early warning signal can be generated, so that the transmission system can be checked and corrected in time. The monitoring method can realize fully automatic measurement and monitoring, improve monitoring efficiency, and can provide feedback processing in time when abnormalities are monitored, thereby reducing the problem of large-scale scrapping or yield reduction caused by abnormal transmission deviation.

[0103] Based on the above-mentioned method for monitoring the transmission deviation of the transmission system, this embodiment also provides a substrate transmission system, which can be specifically referred to in Figure 1As shown, the conveying system includes at least one conveying device 110 for conveying a substrate 200, and the conveying device 110 includes, for example, a conveying arm, etc. Also, the conveying system also includes a detection device 120 and a data processing unit (not shown in the figure), the detection device 120 is arranged on the conveying path of the conveying system, and is used to receive the substrate transmitted from the transmission device 110, and detect the actual position of the substrate 200 on the detection platform 121; and the data processing unit is used to perform data processing on the actual position and theoretical position of the substrate 200 to obtain the offset state of the substrate 200, and determine the transmission deviation of the conveying device along the conveying path of the substrate 200 according to the offset state of the substrate 200. In practical applications, the data processing unit can be directly arranged in the detection device 120; or, the data processing unit can also be externally arranged on other hardware devices, and the data processing unit is connected to the detection device 120 for communication to receive the detection data of the detection device 120.

[0104] In a specific example, the detection device 120 in the conveying system may include an image sensor for identifying at least one measurement mark on the substrate, and when identifying the measurement mark, the center of the image sensor's camera field of view is aligned with the theoretical position of the measurement mark to obtain the offset state of the actual position of the measurement mark relative to the center of the camera field of view, thereby obtaining the offset state of the actual position and theoretical position of the substrate. Furthermore, the data processing unit in the conveying system is also used to generate an early warning message when the identified measurement mark exceeds the control interval. The control interval is specifically set based on the camera field of view of the image sensor, and the center of the control interval coincides with the center of the camera field of view and is within the range of the camera field of view.

[0105] For example, the control area covers about 2 / 3 of the camera field of view FOV. Figure 3 For example, the camera field of view FOV is a rectangle, and the control interval has first control lines UCL_X / LCL_X relative to each other in a first direction (X direction) and second control lines UCL_Y / LCL_Y relative to each other in a second direction (Y direction), and the two first control lines and the two second control lines surround a rectangular control interval, that is, the two first control lines are equidistantly located on both sides of a center line of the camera field of view FOV, and the two second control lines are equidistantly located on both sides of the center line of the camera field of view FOV.

[0106] In addition, the data processing unit can also be used to record the offset detection results of the detection equipment on multiple substrates, which can not only monitor the transmission deviation of the transmission system in real time, but also help to judge the equipment stability of the transmission system. Specifically, when the offset values ​​of multiple detection results gradually increase for a predetermined number of times on the same side of the center line, an early warning message can be generated. For example, seven consecutive offset detection results all show that the offset is continuously and gradually away from the center line.

[0107] In this embodiment, the data processing unit can not only be used to determine whether the offset state of the substrate meets the requirements, but also can further calculate the deflection angle of the substrate, the translation amount in the first direction and the translation amount in the second direction. The specific calculation formulas can refer to Formula 1-Formula 4, which will not be repeated here.

[0108] Furthermore, the conveying system further includes a pre-alignment mechanism 130 for pre-aligning the substrate, including adjusting the deflection direction of the substrate to a predetermined direction, so that each substrate 200 can be conveyed in substantially the same direction in the subsequent conveying path, so that it can reach the target device in the predetermined direction. In this embodiment, the substrate 200 can be preferentially conveyed to the pre-alignment mechanism 130 to pre-align the deflection direction of each substrate 200, and then the substrate is conveyed to the detection device 120, so that each substrate 200 can be placed in the detection device 120 in substantially the same deflection direction.

[0109] The following describes the conveying process of the conveying system and the method for implementing deviation monitoring during the conveying process by giving a specific example. First, the conveying device 110 (such as a conveying arm) can be used to grab the wafer from the wafer box (Foup); then, the wafer is conveyed to the pre-alignment mechanism 130 for pre-alignment processing, and the deflection angle of the wafer is adjusted; then, the conveying device 110 is used to place the wafer on the detection platform 121 of the detection device 120; then, the image sensor 122 in the detection device 120 is used to obtain the substrate image and identify the measurement mark therein to obtain the actual position of the measurement mark. Then, the detection result of the detection device can be sent to the data processing unit (not shown in the figure) to obtain the offset state of the substrate through data processing.

[0110] In a specific example, when the image sensor 122 identifies the measurement mark, the data processing unit can also be used to determine whether the measurement mark exceeds the control interval. If it exceeds the control interval, it means that the transmission system has a large deviation, and an early warning message can be generated at this time. Furthermore, the data processing unit can also continuously collect the detection results of each substrate and save the corresponding data information of the transmission deviation, which is conducive to further determining the equipment stability of the transmission system. At the same time, the data processing unit can also be used to determine whether the offset value of multiple detection results has been gradually increased for a predetermined number of consecutive times on the same side of the center line. If so, an early warning message can be generated to warn the transmission system in advance of the risk of transmission deviation.

[0111] It should be noted that, although the present invention has been disclosed as a preferred embodiment, the above embodiment is not intended to limit the present invention. For any technician familiar with 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 modified into equivalent embodiments of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still belongs to the scope of protection of the technical solution of the present invention.

[0112] It should also be understood that, unless otherwise specified or indicated, the terms "first", "second", "third", etc. in the specification are only used to distinguish the various components, elements, steps, etc. in the specification, rather than to represent the logical relationship or sequential relationship between the various components, elements, steps, etc. It should also be recognized that the terms described herein are only used to describe specific embodiments, rather than to limit the scope of the present invention. It must be noted that the singular forms "one" and "a kind" used herein and in the appended claims include plural references unless the context clearly indicates the opposite meaning. For example, a reference to "a step" or "a device" means a reference to one or more steps or devices, and may include secondary steps and secondary devices. All conjunctions used should be understood in the broadest sense. And, the word "or" should be understood to have the definition of a logical "or", rather than a logical "exclusive or" definition, unless the context clearly indicates the opposite meaning.

Claims

1. A method for monitoring transmission deviation of a transmission system, characterized in that: include: Using at least one transmission device to transfer the substrate, including transferring the substrate to a detection platform of a detection device to detect an actual position of the substrate on the detection platform; as well as, The offset state of the substrate is obtained according to the actual position and theoretical position of the substrate, and the transmission deviation of the transmission device along the transmission path of the substrate is determined according to the offset state of the substrate.

2. The method for monitoring the transmission deviation of a transmission system according to claim 1, characterized in that: The method of obtaining the offset state of the substrate includes: At least one measurement mark on the substrate is identified by using the image sensor of the detection device. When identifying the measurement mark, the center of the camera field of view of the image sensor faces the theoretical position of the measurement mark, so as to obtain the offset state of the actual position of the measurement mark relative to the center of the camera field of view, and obtain the offset state of the actual position and the theoretical position of the substrate.

3. The method for monitoring the transmission deviation of a transmission system according to claim 2, characterized in that: A control interval is also set based on the camera field of view of the image sensor. The center of the control interval coincides with the center of the camera field of view and is located within the range of the camera field of view, and is used to generate warning information when the identified measurement mark exceeds the control interval.

4. The method for monitoring the transmission deviation of a transmission system according to claim 3, characterized in that: The control area covers 2 / 3 of the camera field of view.

5. The method for monitoring the transmission deviation of a transmission system according to claim 4, characterized in that: The camera field of view is a rectangle, and the control interval has two first control lines opposite to each other in a first direction and two second control lines opposite to each other in a second direction, and the two first control lines and the two second control lines surround a rectangular control interval.

6. The method for monitoring the transmission deviation of a transmission system according to claim 2, characterized in that: The monitoring method further includes: recording the offset detection results of the detection device on multiple substrates, and generating warning information when the offset values ​​of multiple detection results gradually increase for a predetermined number of consecutive times on the same side of the center line.

7. The method for monitoring the transmission deviation of a transmission system according to claim 2, characterized in that: A measurement mark is set at the center point of the substrate. When identifying the measurement mark at the center point of the substrate, the camera field of view of the image sensor faces the center of the detection platform to obtain the offset state of the center point of the substrate relative to the center point of the camera field in the substrate image.

8. The method for monitoring the transmission deviation of a transmission system according to claim 1, characterized in that: The detection device determines the offset state of the actual coordinate system of the substrate relative to the theoretical coordinate system by acquiring the coordinate system of the substrate with its center as the origin.

9. The method for monitoring the transmission deviation of a transmission system according to claim 2 or 8, characterized in that: At least two measurement marks are set on the substrate, and the actual position of each measurement mark is obtained by identifying the at least two measurement marks, and the actual position of each identified measurement mark is matched with the theoretical position one by one to obtain the offset state of the substrate.

10. The method for monitoring the transmission deviation of a transmission system according to claim 1, characterized in that: The offset state of the substrate includes a translation amount of the substrate in two-dimensional directions; and / or a deflection angle of the substrate.

11. The method for monitoring the transmission deviation of a transmission system according to claim 1, characterized in that: At least two measurement marks are set on the substrate, the actual positions of the at least two measurement marks are identified, and the translation amount of the substrate in the first direction and the second direction, and the deflection angle of the substrate are obtained according to the following formulas; X A ’=X A *cosθ-Y A *sinθ+△X Y A ’=X A *sinθ+Y A *cosθ+△Y X B ’=X B *cosθ-Y B *sinθ+△X Y B ’=X B *sinθ+Y B *cosθ+△Y Among them, X A is the theoretical value of the first measurement mark in the X direction; X B is the theoretical value of the second measurement mark in the X direction; Y A is the theoretical value of the first measurement mark in the Y direction; Y B is the theoretical value of the second measurement mark in the Y direction; X A ' is the actual value of the first measurement mark in the X direction; X B ' is the actual value of the second measurement mark in the X direction; Y A ' is the actual value of the first measurement mark in the Y direction; Y B ' is the actual value of the second measurement mark in the Y direction; △X is the translation of the substrate in the X direction; △Y is the translation of the substrate in the Y direction; θ is the deflection angle of the substrate.

12. A substrate conveying system, characterized in that: include: at least one transport device for transporting the substrate; A detection device, arranged on a conveying path of the conveying system, for receiving a substrate conveyed from the transmission device and detecting an actual position of the substrate on the detection platform; and The data processing unit is used to process the actual position and theoretical position of the substrate to obtain the offset state of the substrate, and determine the transmission deviation of the transmission device along the transmission path of the substrate according to the offset state of the substrate.

13. The conveying system according to claim 12, characterized in that The detection device includes an image sensor for identifying at least one measurement mark on the substrate, and when identifying the measurement mark, the center of the camera field of view of the image sensor is aligned with the theoretical position of the measurement mark to obtain the offset state of the actual position of the measurement mark relative to the center of the camera field of view, and obtain the offset state of the actual position and theoretical position of the substrate.

14. The conveying system according to claim 13, characterized in that The data processing unit is also used to generate warning information when the identified measurement mark exceeds a control interval, wherein the control interval is set based on the camera field of view of the image sensor, and the center of the control interval coincides with the center of the camera field of view and is within the range of the camera field of view.

15. The conveying system according to claim 14, characterized in that The control area covers 2 / 3 of the camera field of view.

16. The conveying system according to claim 13, characterized in that The data processing unit is also used to record the offset detection results of the detection device on multiple substrates, and generate warning information when the offset values ​​of multiple detection results gradually increase for a predetermined number of consecutive times on the same side of the center line.

17. The conveying system according to claim 12, characterized in that The conveying system further comprises a pre-alignment mechanism for pre-aligning the substrate, including adjusting the deflection direction of the substrate to a predetermined direction.

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