Substrate transfer device and substrate transfer method

Abstract

To provide a transfer technique advantageous for improving throughput.SOLUTION: A substrate transfer device includes a transfer mechanism that transfers and places a substrate on a mounting table along a transfer path, a detector for detecting an edge of the substrate while the substrate is being transferred along the transfer path by the transfer mechanism, a positioning mechanism that positions the mounting table, and a controller that obtains a predicted stop position of the substrate being transferred by the transfer mechanism on the basis of information output from the detector, and causes the positioning mechanism to start an operation for positioning the mounting table for the predicted stop position while the substrate is being transferred by the transfer mechanism.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a substrate transfer device and a substrate transfer method.

Background Art

[0002] In a system having an exposure apparatus for transferring a pattern such as a circuit pattern onto a substrate, alignment of the substrate may be performed before the substrate is transferred to a substrate chuck in order to transfer the substrate to a predetermined position of the substrate chuck. The substrate has a notch such as a notch or an orientation flat as an azimuth reference, and the alignment of the substrate may include an operation of matching the position and azimuth of the substrate with a target position and a target azimuth by detecting the notch. The alignment of the substrate may be performed in a device that detects the notch, or may be performed when transferring the substrate based on the detection result by the device.

[0003] As a method for detecting the position and azimuth of a substrate, a method is known in which the edge of the substrate is detected while rotating the substrate, and the position (center position) and azimuth of the substrate are obtained from a waveform indicating the edge. To implement this method, a device having a detector for detecting the edge of the substrate, a mounting table for holding the substrate, and a mechanism for rotating the mounting table can be used. In such a device, the measurement error due to distortion components or the like of the detector can increase as the amount of deviation of the center of the substrate from the rotation center of the mounting table increases. Therefore, the substrate should be placed on the mounting table with a small deviation amount.

[0004] Patent Document 1 describes that when a wafer is being transferred by a transfer means, the amount of deviation between the center position of the wafer and a reference position is calculated, and the wafer is placed at the center position of the mounting table by the transfer means so as to correct the deviation amount.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0006] However, in the apparatus described in Patent Document 1, for example, when the distance for the transport means to transport the wafer so as to correct the deviation amount is larger than the designed transport distance (the transport distance when the deviation amount is 0), the transport time becomes longer by that amount, and the throughput may decrease.

[0007] An object of the present invention is to provide a transport technique advantageous for improving throughput.

MEANS FOR SOLVING THE PROBLEMS

[0008] A first aspect of the present invention relates to a substrate transport apparatus, the substrate transport apparatus transporting a substrate along a transport path to a mounting table su a transport mechanism for transporting, a detector for detecting an edge of the substrate while the substrate is being transported along the transport path by the transport mechanism multiple times detecting ru a detector, a positioning mechanism for positioning the mounting table, and a controller for causing the positioning mechanism to start an operation of positioning the mounting table with respect to the predicted stop position while the substrate is being transported by the transport mechanism. but based on the results of detecting the edge of the substrate multiple times, corresponding to each result the substrate stops position determine the predicted stop position of the substrate based on this, and while the substrate is being transported by the transport mechanism. A second aspect of the present invention relates to a substrate transfer device. The substrate transfer device includes a transfer mechanism that transfers a substrate along a transfer path to a mounting table, a detector that detects an edge of the substrate while the substrate is being transferred along the transfer path by the transfer mechanism, a positioning mechanism that positions the mounting table, obtains a predicted stop position of the substrate being transferred by the transfer mechanism based on information output from the detector, and a controller that causes the positioning mechanism to start an operation of positioning the mounting table with respect to the predicted stop position while the substrate is being transferred by the transfer mechanism. The positioning mechanism rotates the substrate by rotating the mounting table, the detector detects the edge of the substrate when the substrate is rotating, and the controller executes a detection process of detecting an arrangement error of the substrate placed on the mounting table based on a detection result of the edge of the substrate by the detector when the substrate is rotating. A third aspect of the present invention relates to a substrate transfer method for transferring a substrate along a transfer path to a mounting table by a transfer mechanism. The substrate transfer method includes a determination step of determining a predicted stop position of the substrate being transferred by the transfer mechanism based on information output from a detector that detects an edge of the substrate multiple times while the substrate is being transferred by the transfer mechanism, and a positioning step of positioning the mounting table with respect to the predicted stop position. In the determination step, the predicted stop position of the substrate is determined based on positions where the substrate stops corresponding to each result of the detector detecting the edge of the substrate multiple times, and the positioning step is started while the substrate is being transferred by the transfer mechanism. A fourth aspect of the present invention relates to a substrate transfer method for transferring a substrate to a mounting table along a transfer path by a transfer mechanism. The substrate transfer method includes a step of obtaining a predicted stop position of the substrate being transferred by the transfer mechanism based on information output from a detector that detects an edge of the substrate while the substrate is being transferred by the transfer mechanism, a step of positioning the mounting table with respect to the predicted stop position, and a step of executing a detection process for detecting a placement error of the substrate placed on the mounting table by detecting the edge of the substrate while rotating the mounting table on which the substrate is placed. The step of positioning the mounting table at the predicted stop position is started while the substrate is being transferred by the transfer mechanism.

EFFECTS OF THE INVENTION

[0009] According to the present invention, a transport technique advantageous for improving throughput is provided.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are essential for the invention, and the plurality of features may be arbitrarily combined. Further, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant explanations are omitted. In this specification and the drawings, relative directions are described according to the XYZ coordinate system for convenience.

[0012] FIG. 1 schematically shows the configuration of a substrate transfer apparatus 1 according to the first embodiment. The substrate transfer apparatus 1 may include a scalar robot 150 (transfer mechanism), a detector DT, a positioning mechanism 100, and a controller CNT. The scalar robot 150 has a hand 155, holds a substrate S with the hand 155, and is a transfer mechanism or a transfer robot that transfers and places the substrate S along a transfer path onto a mounting table 120 of the positioning mechanism 100. The detector DT is used to detect the edge of the substrate while the substrate S is being transferred along the transfer path by the scalar robot 150. The detector DT can include a plurality of sensors 111, 112, 113, and can detect the edge of the substrate S using the plurality of sensors 111, 112, 113. The plurality of sensors 111, 112, 113 can be, for example, line sensors or area sensors. The sensors 111, 112 can be arranged such that the directions having resolution (in the case of line sensors, their longitudinal directions) are orthogonal to each other.

[0013] The positioning mechanism 100 may include a mounting table 120 and a drive mechanism 122 that drives the mounting table 120. The drive mechanism 122 can include, for example, a mechanism that rotationally drives the mounting table 120 around an axis parallel to the Z axis, and a mechanism that linearly drives the mounting table 120 in at least one direction within the XY plane. The drive mechanism 122 may further include a mechanism that drives the mounting table 120 in a direction parallel to the Z axis, that is, a lifting mechanism. The detector DT and the positioning mechanism 100 can constitute an alignment apparatus. Here, two directions along the mounting surface of the mounting table 120 on which the substrate S is placed and orthogonal to each other are defined as the directions of the X axis and the Y axis, and the direction orthogonal to the XY plane parallel to the X axis and the Y axis is defined as the direction of the Z axis.

[0014] After the substrate S is placed on the placement table 120, the positioning mechanism 100 rotates the substrate S by rotating the placement table 120, and the detector DT can detect the edge of the substrate S when the substrate S is rotating. The controller CNT can execute a detection process for detecting the arrangement error of the substrate S with respect to the placement table 120. The detection process is, for example, a process of detecting the arrangement error of the substrate S placed on the placement table 120 based on the detection result of the edge of the substrate S by the detector DT when the substrate S is rotating. The controller CNT can control the positioning mechanism 100 so that the position of the substrate S placed on the placement table 120 coincides with the reference position based on the arrangement error detected in the detection process. The detection of the arrangement error of the substrate S may include the detection of the orientation of the substrate S using the notch of the substrate S. In this case, the controller CNT can control the positioning mechanism 100 so that the position and orientation of the substrate S placed on the placement table 120 coincide with the reference position and reference orientation, respectively.

[0015] Alternatively, the controller CNT may perform alignment of the substrate S by controlling the transfer mechanism that transfers the substrate S placed on the placement table 120 based on the arrangement error detected in the detection process. The transfer mechanism may be the scalar robot 150 or another transfer mechanism (not shown).

[0016] The controller CNT can be configured to obtain the predicted stop position of the substrate being transferred by the scalar robot 150 based on the information output from the detector DT. Further, the controller CNT can be configured to cause the positioning mechanism 100 to start an operation of positioning the placement table 120 with respect to the predicted stop position while the substrate is being transferred by the scalar robot 150.

[0017] Figures 2(a) and 2(b) illustrate the operation in which a substrate S having a known diameter is conveyed and placed on the mounting table 120 of the positioning mechanism 100 by the scalar robot 150. Figure 2(a) shows the state where the conveyance of the substrate S to the mounting table 120 is almost completed and the substrate S has entered the detectable regions of the sensors 111 and 112. Figure 2(b) shows the state where the substrate S is placed on the mounting table 120.

[0018] Figure 3(a) shows the driving timing of the mounting table 120 in the first mode. Figure 3(a) also shows, as the detection result by the detector DT, the detection result of the position of the edge of the substrate S using the sensor 112. Here, the "center side" means the side closer to the origin position of the mounting table 120, and the "outer side" means the side farther from the origin position of the mounting table 120. The position of the edge of the substrate S detected using the sensor 112 during the period including the state of Figure 2(a) and the state of Figure 2(b) changes like the curve 201.

[0019] In the first mode, the controller CNT controls the scalar robot 150 so that the substrate S is conveyed onto the mounting table 120, then detects the position of the substrate S by the detector DT, and positions the mounting table 120 with respect to the substrate S based on the detection result. Then, the controller CNT controls the scalar robot 150 so that the substrate S is placed on the mounting table 120.

[0020] Figure 3(b) illustrates the driving timing of the mounting table 120 in the second mode. Figure 3(b) also shows, as the detection result by the detector DT, the detection result of the position of the edge of the substrate S using the sensor 112. Here, the "center side" means the side closer to the origin position of the mounting table 120, and the "outer side" means the side farther from the origin position of the mounting table 120. The position of the edge of the substrate S detected using the sensor 112 during the period including the state of Figure 2(a) and the state of Figure 2(b) changes like the curve 201.

[0021] The controller CNT can be configured to determine a predicted stop position based on the information provided by the scalar robot 150 and the information output from the detector DT in the detection section 231 (information indicating the position of the edge of the substrate S). The predicted stop position is the position of the substrate S at the timing when the conveyance of the substrate S by the scalar robot 150 is stopped (the timing of "conveyance stop" in the figure). Also, the controller CNT can be configured to cause the positioning mechanism 100 to start an operation of positioning the mounting table 120 with respect to the predicted stop position while the substrate S is being conveyed by the scalar robot 150. In the example of FIG. 3(b), immediately after the end of the detection section 231, more specifically, immediately after determining the predicted stop position, an operation of positioning the mounting table 120 with respect to the predicted stop position is started. Such a configuration is advantageous for improving throughput. Here, it is desirable for the controller CNT to control the positioning mechanism 100 so that the positioning of the mounting table 120 with respect to the predicted stop position is completed while the substrate S is being conveyed by the scalar robot 150, which is advantageous for further improving throughput.

[0022] In one example, the controller CNT can determine a predicted stop position based on the information provided by the scalar robot 150 and the information output from the detector DT in the detection section 231 (information indicating the position of the edge of the substrate S). In this example, the controller CNT can determine the relative position between the position of the hand 155 (the position representing the hand 155) and the position of the substrate S (the representative position of the substrate S) based on the position of the hand 155 and the information output from the detector DT in the detection section 231. Then, the controller CNT can determine the predicted stop position based on the position where the hand 155 stops on the mounting table 120 and the relative position. The information provided from the scalar robot 150 to the controller CNT may be, for example, information indicating the position of the hand 155 in real time. Alternatively, the information provided from the scalar robot 150 to the controller CNT may be a drive profile of the hand 155 (for example, time-series data indicating the position of the hand 155), or other information.

[0023] In other examples, the controller CNT may have a prediction model for determining a predicted stop position and may predict or determine the predicted stop position using the prediction model. Inputs to the prediction model may include, for example, the time from the start of conveyance of the substrate S by the scalar robot 150 to the start of the detection section 231, and the position of the edge of the substrate S in the detection section 231. The scalar robot 150 conveys the hand 155 (substrate S) according to a predetermined drive profile. Therefore, the time from the start of conveyance of the substrate S by the scalar robot 150 to the start of the detection section 231 may provide the position of the hand 155 at the timing when the substrate S enters the detection section 231. Inputs to the prediction model may further include the speed of the substrate S obtained from the amount of change in the position of the edge of the substrate S in the detection section 231. This speed may be used to correct the predicted stop position estimated based on the time from the start of conveyance of the substrate S by the scalar robot 150 to the start of the detection section 231 and the position of the edge of the substrate S in the detection section 231, in order to improve the prediction accuracy. The output from the prediction model is the predicted stop position.

[0024] With reference to FIG. 4, the positioning of the mounting table 120 with respect to the predicted stop position will be described. FIG. 4 illustrates the positional relationship between the substrate S and the sensors 111 and 112 in a state where the substrate S is placed (transported) at the predicted stop position by the scalar robot 150. The sensors 111 and 112 are arranged such that their longitudinal directions (the directions having resolution) have angles θ1 and θ2 with respect to the X direction. The position of the edge of the substrate S detected by the sensor 111 is indicated by reference numeral 171, and the deviation of the edge with respect to the reference position R1 is ΔL1. The position of the edge of the substrate S detected by the sensor 112 is indicated by reference numeral 172, and the deviation of the edge with respect to the reference position R2 is ΔL2. The reference positions R1 and R2 coincide with the positions of the edges of the substrate S when the substrate S is arranged such that the center of the substrate S coincides with the origin O of the positioning mechanism 100. Let the position of the center of the substrate S be O'. Then, the vector representing the deviation amount of the representative position (origin O) of the mounting table 120 with respect to the predicted stop position is given by the sum of the vectors of ΔL1 and ΔL2. The X component ΔX and the Y component ΔY of the deviation amount of the representative position (origin O) of the mounting table 120 with respect to the predicted stop position are given by Expressions (1) and (2), respectively. ΔX and ΔY are the driving amounts for driving the mounting table 120 so that the representative position of the mounting table 120 coincides with the predicted stop position.

[0025] ΔX = ΔL1 cos θ1 + ΔL2 cos θ2 ···(1) ΔY = ΔL1 sin θ1 + ΔL2 sin θ2 ···(2) In the second mode, after the detection section 231 and preferably before the completion of the transfer of the substrate S by the scalar robot 150, the controller CNT positions the mounting table 120 in the positioning mechanism 100 so that the representative position of the mounting table 120 coincides with the predicted stop position.

[0026] Here, an example of obtaining the driving amount of the mounting table 120 using the sensors 111 and 112 of the detector DT has been described. However, the number of sensors for obtaining the driving amount may be one or three or more.

[0027] The notch (or orientation flat) of the substrate S may enter the fields of view of the sensors 111 and 112. FIG. 5 shows the operation when the notch of the substrate S enters the field of view of the sensor 112 after the end of the detection section 231. In this case, the position of the edge of the substrate S detected using the sensor 112 changes as shown by the curve 202. However, in the detection section 231, since the notch of the substrate S does not enter the field of view of the sensor 112, the predicted stop position obtained based on the detection result in the detection section 231 is a position following the curve 211 indicating the actual position change of the substrate S and is not affected by the notch. Therefore, the mounting table 120 can be positioned at the predicted stop position without being affected by the notch. Such a form is advantageous when the substrate S to be conveyed by the scalar robot 150 is prepared so that the notch of the substrate S does not enter the field of view of the detector DT (sensors 111 and 112) in the detection section 231.

[0028] FIG. 6 illustrates a method for obtaining a predicted stop position based on information excluding the information on the notch of the substrate S among the information output from the detector DT. In the example shown in FIG. 6, the detection section 231 includes a plurality of detection sections (first detection section 232, second detection section 233, third detection section 234). Therefore, the detector DT detects the edge of the substrate S multiple times while the substrate S is being conveyed along the conveyance path by the scalar robot 150. The controller CNT obtains the positions where the substrate S stops multiple times based on the information output multiple times from the detector DT by detecting the edge of the substrate S multiple times. Then, the controller CNT determines the predicted stop position based on the positions obtained multiple times and controls the alignment mechanism 100 so that the mounting table 120 is positioned at the predicted stop position.

[0029] In the example of FIG. 6, first, in the first detection section 232, the notch portion of the substrate S enters the field of view of the sensor 112. At this point, the change in the position of the edge of the substrate S obtained based on the information output from the sensor 112 is as shown by the curve 212. In the subsequent second detection section 233 and third detection section 234, the notch portion of the substrate S exits the field of view of the sensor 112, and the position of the edge of the substrate S obtained based on the information output from the sensor 112 becomes a position following the curve 203 indicating the actual position of the substrate S. Therefore, the predicted stop position obtained based on the detection results in the second detection section 233 and the third detection section 234 becomes a position following the curve 211 indicating the change in the actual position of the substrate S.

[0030] As described above, the controller CNT can obtain the positions where the substrate S stops multiple times based on the information output multiple times from the detector DT by detecting the edges of the substrate S multiple times by the detector DT. Then, the controller CNT can determine the predicted stop position based on the positions obtained multiple times. The controller CNT may be configured to determine the predicted stop position based on the positions among those obtained multiple times where the variation is within the reference value, and the positioning mechanism 100 can be controlled so that the mounting table 120 is positioned with respect to the predicted stop position. The number of detection sections is, for example, 3 or more.

[0031] The determination of the predicted stop position based on the positions obtained multiple times may be changed or maintained according to the detection results in each detection section, as exemplified below. Here, for the sake of convenience of explanation, the positions where the substrate S stops determined based on the measurement results of the first detection section 232, the second detection section 233, and the third detection section 234 are referred to as the first position, the second position, and the third position, respectively. In the example of FIG. 6, since the second position is different from the first position, the stop prediction position can be changed from the first position to the second position after the end of the second detection section 234. Also, since the third position coincides with the second position, the stop prediction position can be maintained at the second position even after the end of the third detection section 234.

[0032] In another example, when the second position is different from the first position and the third position coincides with the first position, the predicted stop position may be changed from the first position to the second position after the end of the second detection section 234, and may be changed from the second position to the third position (the first position) after the end of the second detection section 234.

[0033] In yet another example, when the second position coincides with the first position and the third position is different from the first and second positions, the predicted stop position may be maintained at the first position even after the end of the second detection section 234, and may be maintained at the first position even after the end of the third detection section 234.

[0034] Intervals 241 and 242 may be provided between adjacent detection sections among the first detection section 232, the second detection section 233, and the third detection section 234. The first detection section 232, the second detection section 233, the third detection section 234, and the intervals 241 and 242 are set to be able to detect changes caused by the notch portion.

[0035] The substrate transfer device 1 may constitute a part of a lithography device or a pattern transfer device typified by, for example, an exposure device and an imprint device.

[0036] FIG. 7 illustrates the operation of the substrate transfer device 1 in the second mode. The operation shown in FIG. 7 can be controlled by the controller CNT. In step S301, the controller CNT causes the scalar robot 150 to start transferring the substrate S. The scalar robot 150 can receive the substrate S from, for example, a cassette or a substrate supply unit (not shown) and start its transfer. In step S302, the detector DT detects the position of the substrate S being transferred by the scalar robot 150. In step S303, while the substrate S is being transferred by the scalar robot 150, the controller CNT obtains a predicted stop position at which the substrate S being transferred by the scalar robot 150 will stop, based on the information output from the detector DT. In step S304, the controller CNT causes the positioning mechanism 100 to start an operation of positioning the mounting table 120 at the predicted stop position obtained in step S303. In step S305, the controller CNT controls the scalar robot 150 so that the substrate S is placed on the mounting table 120. In step S306, the controller CNT causes the alignment device constituted by the detector DT and the positioning mechanism 100 to perform alignment of the substrate S. The alignment of the substrate S may include a detection process of detecting the edge of the substrate S by the detector DT while rotating the substrate S by rotating the mounting table 120 by the drive mechanism 122, and detecting the arrangement error of the substrate S based on the detection result. Further, the alignment of the substrate S may include a process of driving the mounting table 120 (substrate S) so that the position of the substrate S placed on the mounting table 120 coincides with the reference position, based on the arrangement error detected in the detection process.

[0037] In step S306, the controller CNT obtains the placement error detected in the detection process. In step S307, the controller CNT determines whether the placement error is within the tolerance. If the placement error is within the tolerance, the operation shown in FIG. 7 ends. If the placement error is outside the tolerance, the process proceeds to step S309. In step S309, the controller CNT determines whether the number of consecutive times the placement error has been outside the tolerance is less than a specified number. If the number of consecutive times is less than the specified number, the operation shown in FIG. 7 ends. If the number of consecutive times is greater than or equal to the specified number, the process proceeds to step S310. Instead of determining whether the number of consecutive times is less than the specified number, it may be determined whether the number of consecutive times is less than a specified frequency. The determination in step S309 takes into account the possibility that the placement error is due to an abnormality in an individual substrate, such as the adhesion of foreign matter to the substrate S or a defect in the edge of the substrate S.

[0038] In step S310, the controller CNT corrects a prediction model for determining a predicted stop position based on the placement error. In step S311, the controller CNT determines whether the correction amount of the prediction model in step S310 is less than or equal to an acceptable amount. If the correction amount is less than or equal to the acceptable amount, the operation shown in FIG. 7 ends. On the other hand, if the correction amount exceeds the acceptable amount, in step S312, the controller CNT notifies of the occurrence of an abnormality. Instead of the above operation, the controller CNT may notify at the time when the prediction model is corrected in step S310.

[0039] The second embodiment will be described with reference to FIGS. 8 and 9. Matters not mentioned as the second embodiment may follow the first embodiment. In the second embodiment, the substrate S is conveyed in the direction indicated by the arrow in FIG. 8(a). In this case, at the position where the conveyance of the substrate S stops, as shown in FIG. 8(b), the arm or hand 155 of the scalar robot 150 is disposed between the sensor 112 and the substrate S, and the edge of the substrate S cannot be detected by the sensor 112.

[0040] In the second embodiment, the substrate transfer device 1 has different detection sections by the sensor 111 and the sensor 112. In FIG. 9(a), the detection section 247 by the sensor 112 is illustrated, and in FIG. 9(b), the detection section 248 by the sensor 111 is illustrated. In FIGS. 9(a) and 9(b), the horizontal axis represents the same time. When the transfer of the substrate S by the scalar robot 150 is started, first, as illustrated in FIG. 9(a), the controller CNT can obtain a waveform 245 indicating the edge of the substrate S using the sensor 112. In the detection section 247, the controller CNT can compare the preset reference waveform 249 with the detected waveform 245 to detect the position of the substrate S or the relative position between the hand 155 and the substrate S. Next, as illustrated in FIG. 9(b), the controller CNT can obtain a waveform 246 indicating the edge of the substrate S using the sensor 111. In the detection section 248, the controller CNT can compare the preset reference waveform 250 with the detected waveform 246 to detect the position of the substrate S or the relative position between the hand 155 and the substrate S. In this example, the controller CNT detects the position of the substrate S in a direction orthogonal to the transfer direction of the substrate S. The controller CNT may detect the XY-direction position of the substrate S by using the output of the sensor 113.

[0041] The controller CNT can detect the position of the substrate S based on the information excluding the information on the notch portion of the substrate S among the information output from the detector DT, and can obtain the predicted stop position based on that position. Thereby, the controller CNT can obtain the position of the substrate S and the predicted stop position without being affected by the notch portion.

[0042] In the first embodiment, the detection sections by the sensor 111 and the sensor 112 may be made different. Also, the predicted stop position may be determined using the sensors 111, 112, and 113, and in this case, the detection sections by the sensors 111, 112, and 113 may be different detection sections from each other.

[0043] The third embodiment will be described with reference to FIGS. 10 and 11. Matters not mentioned as the third embodiment may follow the first or second embodiment. In the third embodiment, the sensor 161 of the detection unit DT is arranged so as to be able to detect the shape of at least a part of the edges over the entire circumference of the substrate S. The sensor 161 is, for example, a line sensor or an area sensor. When the sensor 161 is a line sensor, the direction of the line sensor and the conveyance direction of the substrate S can be determined so that the edges of the substrate S are continuously detected by the line sensor in a part of the section during the conveyance of the substrate S. Thereby, the controller CNT can detect the shape of at least a part of the edges over the entire circumference of the substrate S based on the output of the line sensor. In a configuration where the sensor 161 is an area sensor and an image of the edge of the substrate S is projected onto the area sensor, the shape of the edge can be detected by imaging the edge of the substrate S with the area sensor.

[0044] FIG. 11(a) shows an example in which the edge of the substrate S conveyed by the scalar robot 150 is detected by a line sensor as the sensor 161. The horizontal axis represents the position of the hand 155 of the scalar robot 150, and the vertical axis represents the position of the edge of the substrate S. By the conveyance of the substrate S by the scalar robot 150, the position of the edge detected by the line sensor changes, and a curve 251 indicating the position of the edge of the substrate S corresponding to the position of the hand 155 of the scalar robot 150, that is, the shape of the edge, can be obtained. The controller CNT can approximate the curve 251 by the quadratic least squares method or the like to determine an approximate curve 252.

[0045] When the edge of the notch portion of the substrate S is detected, the curve 251 may be distorted under the influence of the notch portion. The controller CNT can extract information 261 and 262 excluding the information of the notch portion from the information output from the detector DT as illustrated in FIG. 11(b) by comparing the designed shape of the substrate S with the curve 251. Further, the controller CNT can obtain a predicted stop position based on the extracted information 261 and 262.

[0046] The invention is not limited to the above embodiments, and various changes and modifications are possible without departing from the spirit and scope of the invention. Therefore, the claims are appended to disclose the scope of the invention.

Explanation of Reference Numerals

[0047] 1: Substrate transfer device, 100: Positioning mechanism, 120: Mounting table, 150: Scalar robot, DT: Detector DT, CNT: Controller

Claims

1. A transport mechanism for transporting a substrate along a transport path to a mounting table, a detector for detecting an edge of the substrate a plurality of times while the substrate is being transported along the transport path by the transport mechanism, a positioning mechanism for positioning the mounting table, a controller that determines a predicted stop position of the substrate based on positions where the substrate stops corresponding to each result of the detector detecting the edge of the substrate a plurality of times, and starts an operation of positioning the mounting table with respect to the predicted stop position while the substrate is being transported by the transport mechanism; A substrate transfer device, characterized by comprising the above.

2. The controller controls the positioning mechanism so that positioning of the mounting table with respect to the predicted stop position is completed while the substrate is being transported by the transport mechanism. The substrate transfer device according to claim 1, characterized by the above.

3. The controller obtains the predicted stop position based on information other than information on a notch portion of the substrate among information output from the detector. The substrate transfer device according to claim 1 or 2, characterized by the above.

4. The controller determines the predicted stop position based on a position among positions where a plurality of the substrates stop and whose variation is within a reference value. The substrate transfer device according to claim 1, characterized by the above.

5. The controller extracts information excluding information on the notch portion from information output from the detector, and obtains the predicted stop position based on the extracted information. The substrate transfer device according to claim 3, characterized by the above.

6. The positioning mechanism rotates the substrate by rotating the mounting table, the detector detects an edge of the substrate while the substrate is rotating, and the controller executes a detection process for detecting a placement error of the substrate placed on the mounting table based on a detection result of the edge of the substrate by the detector while the substrate is rotating. The substrate transfer device according to any one of claims 1 to 5, characterized by the above.

7. The controller is configured to determine the predicted stop position based on information output from the detector and a prediction model, and the controller corrects the prediction model based on the placement error detected in the detection process. The substrate transfer device according to claim 6, characterized by the above.

8. The controller controls the positioning mechanism so that the position of the substrate placed on the placement table coincides with a reference position based on the placement error detected in the detection process. The substrate transfer device according to claim 7, characterized in that.

9. A transfer mechanism that transfers a substrate along a transfer path to a placement table, A detector that detects an edge of the substrate while the substrate is being transferred along the transfer path by the transfer mechanism, A positioning mechanism that positions the placement table, A controller that obtains a predicted stop position of the substrate being transferred by the transfer mechanism based on information output from the detector, and starts an operation of positioning the placement table with respect to the predicted stop position while the substrate is being transferred by the transfer mechanism. The positioning mechanism rotates the substrate by rotating the placement table, and the detector detects an edge of the substrate when the substrate is rotating. The controller executes a detection process of detecting a placement error of the substrate placed on the placement table based on a detection result of the edge of the substrate by the detector when the substrate is rotating. A substrate transfer device characterized by that.

10. A substrate transfer method for transferring a substrate along a transfer path to a placement table by a transfer mechanism, A determination step of determining a predicted stop position of the substrate being transferred by the transfer mechanism based on information output from a detector that detects an edge of the substrate a plurality of times while the substrate is being transferred by the transfer mechanism, A positioning step of positioning the placement table with respect to the predicted stop position, including In the determination step, the predicted stop position of the substrate is determined based on positions where the substrate stops corresponding to each result of the detector detecting the edge of the substrate a plurality of times. The positioning step is started while the substrate is being transferred by the transfer mechanism. A substrate transfer method characterized by that.

11. The step of positioning the placement table ends while the substrate is being transferred by the transfer mechanism. The substrate transfer method according to claim 10, characterized in that.

12. In the step of obtaining the predicted stop position, the predicted stop position is obtained based on information excluding information on a notch portion of the substrate among information output from the detector while the substrate is being transferred by the transfer mechanism. The substrate transfer method according to claim 10 or 11, characterized in that...

13. In the step of positioning the mounting table, the predicted stop position is determined based on a position among the positions where a plurality of the substrates stop, and the variation at the position is within a reference value. The substrate transfer method according to claim 10, characterized in that...

14. In the step of obtaining the predicted stop position, information excluding the information of the notch portion is extracted from the information output from the detector, and the predicted stop position is obtained based on the extracted information. The substrate transfer method according to claim 12, characterized in that...

15. The method further includes a step of executing a detection process for detecting an arrangement error of the substrate placed on the mounting table by detecting an edge of the substrate while rotating the mounting table on which the substrate is placed. The substrate transfer method according to any one of claims 10 to 14, characterized in that...

16. In the step of positioning the mounting table, the predicted stop position is predicted based on the information output from the detector and a prediction model. The substrate transfer method further includes a step of correcting the prediction model based on the arrangement error detected in the detection process. The substrate transfer method according to claim 15, characterized in that...

17. The method further includes a step of positioning the substrate so that the position of the substrate coincides with a reference position based on the arrangement error detected in the detection process. The substrate transfer method according to claim 16, characterized in that...

18. A substrate transfer method for transferring a substrate along a transfer path to a mounting table by a transfer mechanism, including: a step of obtaining a predicted stop position of the substrate being transferred by the transfer mechanism based on information output from a detector that detects an edge of the substrate while the substrate is being transferred by the transfer mechanism; a step of positioning the mounting table with respect to the predicted stop position; a step of executing a detection process for detecting an arrangement error of the substrate placed on the mounting table by detecting an edge of the substrate while rotating the mounting table on which the substrate is placed; and the step of positioning the mounting table at the predicted stop position is started while the substrate is being transferred by the transfer mechanism. The substrate transfer method, characterized in that...

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