SUBSTRATE PROCESSING SYSTEM, ALIGNMENT DEVICE, AND SUBSTRATE SHAPE MONITORING METHOD

Abstract

To provide a technique capable of suppressing erroneous detection of a contour of a substrate when detecting a contour position by rotating the substrate.SOLUTION: A substrate processing system includes: a mounting table on which a substrate is mounted; a rotation mechanism unit which rotates the mounting table; a sensor which detects a contour of the substrate during the rotation of the substrate; and a control device. The control device controls the steps of: (a) rotating the mounting table at a first speed and a first acceleration when first rotating the substrate; (b) referring to information about a contour position of the substrate detected by the sensor when the mounting table is once rotated from a rotation start point to a rotation end point, to determine whether or not a deviation amount of the contour position of the substrate at the rotation start point and the rotation end point is equal to or greater than a threshold; and (c) rotating the mounting table at a second speed lower than the first speed and / or a second acceleration lower than the first acceleration in a case where it is determined that the deviation amount of the contour position of the substrate is equal to or greater than the threshold, and performing a retry operation of the determination in (b).SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present disclosure relates to a substrate processing system, an alignment apparatus, and a method for monitoring a substrate shape. [Background technology]

[0002] Patent Document 1 discloses a substrate alignment device that calculates the amount and direction of eccentricity of a wafer relative to a mounting table by rotating the substrate (wafer) placed on the mounting table and detecting the outer peripheral position of the wafer. A wafer placed on the mounting table may slip from the mounting table due to centrifugal force or the like when the mounting table rotates. When a slip occurs in the wafer, the rotation start point and rotation end point do not match when detecting the outer peripheral position of the wafer, and the alignment device erroneously detects the slip as a chip (error) in the wafer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-47654 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a technique that can suppress erroneous detection of the outer shape of a substrate when detecting the outer shape position by rotating the substrate. [Means for solving the problem]

[0005] According to one aspect of the present disclosure, there is provided a substrate processing system for processing a substrate, the substrate processing system including a mounting table for mounting the substrate, a rotation mechanism for rotating the mounting table, a sensor for detecting the outer position of the substrate while the substrate is rotating, and a control device, wherein the control device controls the following steps: (a) when rotating the substrate for the first time, rotating the mounting table at a first speed and a first acceleration; (b) when rotating the mounting table once from the rotation start point to the rotation end point, referring to information on the outer position of the substrate detected by the sensor, determining whether the deviation amount of the outer position of the substrate between the rotation start point and the rotation end point is equal to or greater than a threshold; and (c) when it is determined that the deviation amount of the outer position of the substrate is equal to or greater than the threshold, rotating the mounting table at a second speed lower than the first speed and / or a second acceleration lower than the first acceleration, and performing a retry operation of the determination of (b). [Effects of the Invention]

[0006] According to one aspect, when detecting the outer shape position by rotating the substrate, erroneous detection of the outer shape of the substrate can be suppressed. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a plan view schematically illustrating an overall configuration of a substrate processing system according to an embodiment. [Figure 2] FIG. 2 is a schematic perspective view showing a state in which a wafer is placed on a placement table inside the alignment device. [Figure 3] FIG. 2 is a schematic perspective view showing a partial configuration of the alignment device when no wafer is present. [Figure 4] FIG. 2 is a block diagram illustrating an example of a hardware configuration of a control device. [Figure 5] 10A and 10B are diagrams illustrating an example of inspection of the outer shape of a wafer by a sensor. [Figure 6] FIG. 2 is a block diagram showing functional blocks of the control device according to the first embodiment. [Figure 7] FIG. 10 is a diagram showing settings of rotation speeds of a mounting table and a wafer. [Figure 8]3 is a flowchart showing a processing flow of a substrate shape monitoring method according to the first embodiment. [Figure 9] FIG. 10 is a block diagram showing functional blocks of a control device of a substrate processing system according to a second embodiment. [Figure 10] 10 is a flowchart showing a processing flow of board shape monitoring broadcasting according to the second embodiment. [Figure 11] 11 is a flowchart showing a speed determination process subroutine of FIG. 10. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and redundant explanations may be omitted.

[0009] [Common embodiment] 1 is a plan view schematically illustrating the overall configuration of a substrate processing system 1 according to one embodiment. As shown in FIG. 1, the substrate processing system 1 is configured as a multi-chamber type having multiple process modules PM. The substrate processing system 1 is used in one process of semiconductor manufacturing, and transfers a substrate from a front module FM via a transfer module TM to a predetermined process module PM, where the substrate is subjected to appropriate substrate processing in the process module PM.

[0010] The substrate to be subjected to the substrate processing may be a silicon semiconductor wafer, a compound semiconductor wafer, an oxide semiconductor wafer, or the like (hereinafter, the substrate may also be referred to as a wafer W). The wafer W is formed into a circular disk having a perfect circular shape in a plan view. The wafer W may have a recess pattern such as a trench or a via.

[0011] The substrate processing system 1 loads the wafer W from an atmospheric atmosphere into a vacuum atmosphere and unloads the wafer W from the vacuum atmosphere into the atmospheric atmosphere in order to perform substrate processing on the wafer W in a vacuum atmosphere. Specifically, the substrate processing system 1 includes a front module FM (e.g., an Equipment Front End Module (EFEM)) and a load lock module LLM. The substrate processing system 1 also includes a control device 80 that controls the operation of the entire system.

[0012] The front module FM has a plurality of load ports 11, a series of loaders 12 adjacent to each load port 11, an atmospheric transfer device 13 provided within the loader 12, and an alignment device (orienter) 14 provided adjacent to the loader 12.

[0013] A FOUP (Front Opening Unified Pod) containing wafers W or an empty FOUP is set in each load port 11. The loader 12 has a rectangular box body with a clean space inside. The loader 12 is equipped with an airflow mechanism (not shown) that supplies clean air to the clean space. The load ports 11 are arranged side by side along the long side of the loader 12. A gate door 11a that opens and closes the clean space is provided between each load port 11 and the loader 12.

[0014] The atmospheric transfer device 13 has a pair of bifurcated forks 13a that support the outer periphery of the backside of the wafer W, and transfers the wafer W in an atmospheric atmosphere. For example, the atmospheric transfer device 13 removes the wafer W from a FOUP set in each load port 11 and transfers the wafer W into a clean space in the loader 12. The atmospheric transfer device 13 then transfers the wafer W from the loader 12 to the alignment device 14, which aligns the wafer W. The atmospheric transfer device 13 then receives the wafer W aligned by the alignment device 14 and transfers the wafer W into the load lock module LLM via the clean space. When a processed wafer W is transferred from the transfer module TM to the load lock module LLM, the atmospheric transfer device 13 transfers the wafer W out of the load lock module LLM and places the wafer W into the FOUP via the clean space in the loader 12.

[0015] The load lock module LLM is provided between the front module FM and the transfer module TM. The load lock module LLM has two load lock vessels 21 that can be switched between an atmospheric atmosphere and a vacuum atmosphere. A gate 22 equipped with a valve (not shown) that airtightly closes the load lock vessels 21 is provided between the load lock module LLM and the front module FM. A gate 23 equipped with a valve (not shown) that airtightly closes the load lock vessels 21 is provided between the load lock module LLM and the transfer module TM. Furthermore, the load lock module LLM has a stage 24 inside the load lock vessel 21 on which a wafer W can be placed.

[0016] One of the two load lock containers 21 accommodates a wafer W transferred from the front module FM in an atmospheric atmosphere and then depressurizes it to a vacuum atmosphere, thereby enabling the wafer W to be transferred to the transfer module TM. The other of the two load lock containers 21 accommodates a wafer W transferred from the transfer module TM in a vacuum atmosphere and then increases the pressure to an atmospheric atmosphere, thereby enabling the wafer W to be transferred to the front module FM. Note that the load lock module LLM may be configured to include one load lock container 21 between the front module FM and the transfer module TM.

[0017] The transfer module TM and the multiple process modules PM transfer wafers W and perform substrate processing in a vacuum atmosphere. In the substrate processing system 1 according to this embodiment, four process modules PM (first process module PM1, second process module PM2, third process module PM3, and fourth process module PM4) are connected to one transfer module TM. It should be noted that the number of process modules PM in the substrate processing system 1 is not particularly limited.

[0018] The transfer module TM includes a transfer container 31 that can be depressurized to a vacuum atmosphere, and a vacuum transfer device 32 installed inside the transfer container 31. The transfer container 31 is formed as a flat hexagonal (polygonal) box in a plan view. A plurality of (two) process modules PM are arranged on each of a pair of long sides of the transfer container 31.

[0019] The vacuum transfer device 32 is configured to be movable horizontally and vertically and to be rotatable by θ in the horizontal direction within the transfer container 31. The vacuum transfer device 32 also includes two transfer arms that can operate independently of each other to exchange an unprocessed wafer W with a processed wafer W for the load lock module LLM or each process module PM.

[0020] The multiple process modules PM are connected to the side of the transfer container 31 in the X-axis direction, which extends in the Y-axis direction. Specifically, the first process module PM1 and the second process module PM2 are provided side by side on one side of the transfer container 31. Furthermore, the third process module PM3 and the fourth process module PM4 are provided side by side on the other side of the transfer container 31.

[0021] Each process module PM has a processing chamber 51 that accommodates a wafer W and performs substrate processing therein. Between the transfer chamber 31 and each processing chamber 51, a gate 52 is provided that communicates with the spaces between them and allows the wafer W to pass through. A valve (not shown) is installed inside each gate 52 to open and close the processing chamber 51. The substrate processing performed by each process module PM may be any of a film formation process, an etching process, an ashing process, a cleaning process, etc. Furthermore, each process module PM may perform the same substrate processing or may perform different substrate processing. The substrate processing system 1 may be configured to perform multiple substrate processing operations (multiple types) consecutively via each process module PM, or may be configured to immediately unload a substrate from the substrate processing system 1 after one substrate processing operation has been performed in any of the process modules PM.

[0022] Next, the alignment device 14 provided in the front module FM of the substrate processing system 1 will be described with reference to Figures 2 and 3. Figure 2 is a schematic perspective view showing a state in which a wafer W is placed on a mounting table 141 inside the alignment device 14. Figure 3 is a schematic perspective view showing a partial configuration of the alignment device 14 in a state in which the wafer W is not present.

[0023] The alignment device 14 includes a mounting table 141 on which the wafer W is placed, a spindle 142 that supports the mounting table 141, and a rotation mechanism 143 connected to the lower end of the spindle 142. The alignment device 14 rotates the mounting table 141 and the spindle 142 about a vertical axis by the rotation drive of the rotation mechanism 143. Inside the rotation mechanism 143, there are provided a motor 143a serving as a drive source, a rotation transmission mechanism (not shown) that transmits the rotation drive of the motor 143a, and an encoder 144 that detects the rotation angle (rotation speed) of the motor 143a or the spindle 142.

[0024] The planar shape of the mounting table 141 is formed into a circular shape that is smaller than the planar shape of the wafer W. The diameter of the mounting table 141 is set smaller than the distance between the pair of forks 13a of the atmospheric transfer device 13 (see FIG. 1). Therefore, when the atmospheric transfer device 13 carries the wafer W into the alignment device 14, the pair of forks 13a are lowered from above to below the mounting table 141, thereby mounting the wafer W on the mounting table 141. As a result, the center of the back surface of the wafer W is mounted on the upper surface of the mounting table 141.

[0025] The mounting table 141 is made of, for example, aluminum, and has a plurality of holding members 145 provided on its upper surface 141s, as shown in FIG. 3. Each holding member 145 is fitted into a plurality of recesses (not shown) formed in the upper surface 141s of the mounting table 141, and protrudes slightly from the upper surface 141s. The holding members 145 are arranged at equal intervals on the same circumference, with the center of rotation of the upper surface 141s of the mounting table 141 as the base point. Each holding member 145 is made of, for example, a material such as rubber or resin that is elastic and has a high coefficient of friction. Each holding member 145 generates friction between itself and the wafer W, thereby suppressing slippage.

[0026] 2, the alignment device 14 includes a sensor 146 that detects the outer shape (shape of the outer peripheral edge) of the wafer W on the radially outer side of the mounting table 141. The sensor 146 may be, for example, a transmissive optical sensor including a light-emitting unit 147 formed by a light-emitting element such as a light-emitting diode, and a light-receiving unit 148 formed by a light-receiving element such as a photodiode, a CCD sensor, or a CMOS sensor. The configuration of the sensor 146 is not particularly limited, and may be, for example, a reflective optical sensor.

[0027] The light receiving unit 148 has a plurality of light receiving elements arranged along the radial direction of the mounting table 141, and generates a voltage drop corresponding to the number of light receiving elements that receive light. That is, in detecting the outer shape position of the wafer W, a portion of the light emitted from the light emitting unit 147 is blocked by the wafer W placed on the mounting table 141, while the remainder of the emitted light is received by the light receiving unit 148. The output value of the light receiving unit 148 of the sensor 146 is the amount of light received that reaches the light receiving unit 148 without being blocked by the wafer W, i.e., a value corresponding to the position of the outer shape (outer periphery) of the wafer W.

[0028] Next, the configuration of the control device 80 of the substrate processing system 1 will be described with reference to Fig. 4. Fig. 4 is a block diagram illustrating an example of the hardware configuration of the control device 80.

[0029] The control device 80 may be a computer in which a processor 81, memory 82, timer 83, an input / output interface (not shown), etc. are connected via a bus 54. The processor 81 is one or a combination of a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), a circuit made up of a plurality of discrete semiconductors, etc. The memory 82 is an appropriate combination of volatile memory and non-volatile memory (for example, a compact disc, a DVD (Digital Versatile Disc), a hard disk, a flash memory, etc.).

[0030] The memory 82 stores a program P for operating the substrate processing system 1 and a recipe for the process conditions of the substrate processing, etc. A storage unit for storing the type of wafer W and the rotation speed of the mounting table 141 when it is determined that the amount of deviation of the wafer W, which will be described later, is less than a threshold value, may be realized by the memory 82. The processor 81 controls each component of the substrate processing system 1 by reading and executing the program P from the memory 82. The substrate processing system 1 may be configured such that a control unit (not shown) is provided for each module, and the control device 80 issues commands to each control unit to control the entire system, or such that the control device 80 centrally controls the operation of each module. The control device 80 may be configured as a host computer or multiple client computers that communicate with each other via a network.

[0031] A user interface 86, a motor 143a, an encoder 144, a sensor 146, and the like are connected to the control device 80 via an input / output interface. A detection signal detected by a light receiving unit 148 of the sensor 146 is transmitted to the control device 80 via an A / D converter (analog / digital conversion unit) 85 and stored in a memory 82 of the control device 80. The information on the outer shape of the wafer W stored in the memory 82 is used to determine whether the outer shape of the wafer W is normal or abnormal, and to calculate the amount and direction of eccentricity.

[0032] 5A and 5B are diagrams illustrating an example of inspection of the outer shape of the wafer W by the sensor 146, in which (A) is an image diagram showing the positional deviation of the wafer W as the wafer W rotates, and (B) is a graph illustrating outer shape data based on the outer shape information of the wafer W detected by the sensor 146. As shown in Fig. 5, the control device 80 controls the alignment device 14 to rotate the wafer W once (360°) at a set rotation speed. Then, while the wafer W is rotating, the control device 80 detects the outer shape position of the wafer W along the circumferential direction of the wafer W using the sensor 146.

[0033] The control device 80 receives the detection signal (information on the outer peripheral position of the wafer W) detected by the sensor 146 and stores the signal in the memory 82 in association with the position of the wafer W in the rotational direction. For example, the control device 80 calculates the position of the wafer W in the rotational direction based on the rotation speed and the sampling period by repeating the detection by the sensor 146 for each predetermined sampling period. This allows the control device 80 to store in the memory 82 outer peripheral data that associates the position of the wafer W in the rotational direction for each sampling period with the outer peripheral position of the wafer W received from the sensor 146.

[0034] Furthermore, the wafer W according to this embodiment has a notch n at a predetermined location on the outer periphery, which is formed by cutting the outer periphery radially inward. The control device 80 can recognize the position of the notch n of the wafer W by detecting a large positional change Rc of the wafer W at the notch n when the outer shape is detected by the sensor 146. The recognized position of the notch n of the wafer W is used by the alignment device 14 to align the circumferential position (rotational position) of the wafer W with respect to the atmospheric transfer device 13.

[0035] Although the alignment device 14 prevents the wafer W from slipping using the holding members 145 of the mounting table 141, the wafer W may slip relative to the mounting table 141 during rotation due to factors such as the position of the wafer W placed on the mounting table 141 and centrifugal force associated with rotation. When the wafer W does not slip relative to the mounting table 141 during rotation, the outer position of the wafer W is detected as shown by the dotted line in FIG. 5(B) during one rotation of the mounting table 141. In this case, the outer position of the wafer W at the start of rotation (hereinafter referred to as the rotation start point Rs) and the outer position of the wafer W at the end of rotation (hereinafter referred to as the rotation end point Re) approximately coincide with each other. However, if the wafer W slips, the outer position of the wafer W is detected as shown by the solid line in FIG. 5(B) during one rotation of the mounting table 141, and the rotation start point Rs and the rotation end point Re are misaligned, as shown by the solid lines in FIGS. 5(A) and 5(B).

[0036] That is, due to the slip of the wafer W, the detection signal (voltage value) output by the light receiving portion 148 of the sensor 146 also changes, and the outer peripheral position of the wafer W received from the sensor 146 is stored in the memory 82 as outer peripheral data showing different heights at the start and end of rotation, as shown in Fig. 5(B). When a positional deviation occurs between the rotation start point Rs and the rotation end point Re in this way, the control device 80 cannot determine whether or not the change in outer peripheral position is due to the notch n of the wafer W, and will erroneously detect an abnormality in the position of the notch n or the shape of the wafer W.

[0037] Specifically, slippage of the wafer W will be described in detail using the contour data illustrated in FIG. 5B. The contour data indicated by the solid line, in which slippage occurs as the wafer W rotates, deviates from ideal contour data (see the dotted line) in which no slippage occurs in the wafer W at the beginning of the wafer W's rotation and at an intermediate stage of the wafer W's rotation. The slippage of the wafer W at the beginning of the rotation occurs during an acceleration period in which the mounting table 141 is increasing its rotation speed to a target rotation speed. That is, the force (change in kinetic energy: impulse) due to the large acceleration during rotation of the mounting table 141 becomes greater than the frictional force between each holding member 145 and the wafer W, which can cause the wafer W to slip from the mounting table 141. On the other hand, the slippage of the wafer W at an intermediate stage of the rotation occurs during a constant speed period in which the mounting table 141 is rotating at a constant rotation speed (target speed). In this case, the deviation occurs due to the centrifugal force acting on the wafer W due to the rotation speed of the mounting table 141. That is, the slip of the wafer W may occur due to the acceleration of the mounting table 141 (including the deceleration when the rotation is stopped) or due to the constant speed of the mounting table 141. In some cases, both factors are combined as shown in FIG. 5B, and in other cases, only one of the factors is involved.

[0038] Such misalignment between the rotation start point Rs and the rotation end point Re is caused by a high rotation speed or acceleration of the wafer W. Therefore, if a misalignment between the rotation start point Rs and the rotation end point Re occurs when the controller 80 rotates the wafer W at an initial speed (first speed) and initial acceleration (first acceleration) to initially detect the outer shape position of the wafer W, the controller 80 rotates the wafer W at a second speed and / or a second acceleration slower than the initial speed. The second speed and second acceleration may be set to gradually lower speeds and accelerations, or may be set to the minimum speed and acceleration at which slip of the wafer W does not occur relative to the mounting table 141 by performing experiments, simulations, or the like. The controller 80 then redetects the outer shape of the wafer W while rotating at the second speed and / or the second acceleration using the sensor 146. As a result, if the rotation start point Rs and the rotation end point Re coincide with each other, it can be recognized that a misalignment of the wafer W occurred due to slip during the previous rotation.

[0039] [First embodiment] To perform the above processing, the control device 80 according to the first embodiment forms functional units as shown in FIG. 6 when the alignment device 14 detects the outer shape position of the wafer W. FIG. 6 is a block diagram showing functional blocks of the control device 80 according to the first embodiment. Specifically, the control device 80 includes a speed acquisition unit 90, a rotation control unit 91, an outer shape data acquisition unit 92, a data storage area 93, a judgment processing unit 94, and a correction amount calculation unit 95.

[0040] The speed acquisition unit 90 acquires information (actual speed) of the rotation speed of the motor 143 a or the support shaft 142 detected by the encoder 144 , stores it in the memory 82 , and outputs it to the rotation control unit 91 .

[0041] The rotation control unit 91 generates speed command information based on a preset target speed and the actual speed acquired by the speed acquisition unit 90 so that the actual speed becomes the target speed. The target speed is, for example, an initial speed (first speed) stored in the data storage area 93 at the initial stage after the wafer W is placed on the mounting table 141, which is read by the rotation control unit 91. The initial speed is information including initial acceleration, such as the speed increase until the speed reaches a constant speed (target speed) and the speed decrease from the constant speed until the wafer W stops. Furthermore, in a "retry operation" in which the detection of the outer peripheral position of the wafer W and the determination of whether the deviation amount between the rotation start point Rs and the rotation end point Re is within an allowable range are performed again, a second speed (minimum speed in this embodiment) set by the determination processing unit 94 is acquired and used as the target speed. The minimum speed is also information including minimum acceleration, such as the speed increase until the speed reaches a constant speed (target speed) and the speed decrease from the constant speed until the wafer W stops. The rotation control unit 91 then transmits the generated speed command information to a driver (not shown), which adjusts the amount of power supplied to the motor 143a to control the rotation speed of the motor 143a. This allows the rotation mechanism 143 of the alignment device 14 to rotate the mounting table 141 and the wafer W at the commanded target speed.

[0042] The outer shape data acquisition unit 92 acquires the detection signal (information on the outer shape of the wafer W) detected by the sensor 146 and stores it in the data storage area 93 of the memory 82 as outer shape data linking the rotational position of the wafer W with the outer shape position of the wafer W.

[0043] The determination processing unit 94 reads the contour data stored in the data storage area 93, determines the contour position of the wafer W, calculates the amount of eccentricity of the wafer W, and, if necessary, resets the rotation speed of the mounting table 141. To this end, the determination processing unit 94 includes a shape determination unit 94a, a speed determination unit 94b, a speed setting unit 94c, and an eccentricity determination unit 94d.

[0044] Based on the outer shape data read from the data storage area 93, the shape determination unit 94a determines whether the rotation start point Rs and the rotation end point Re coincide with each other or whether the amount of deviation between the rotation start point Rs and the rotation end point Re is within an allowable range. For example, the shape determination unit 94a calculates the difference Δr (amount of positional deviation: see FIG. 5) between the rotation start point Rs and the rotation end point Re and determines whether the calculated difference Δr is equal to or greater than a shape determination threshold (not shown). Because the direction of deviation of the wafer W is unknown, it is preferable to calculate the difference Δr as an absolute value. Then, if the difference Δr is less than the shape determination threshold, the shape determination unit 94a determines that the outer shape of the wafer W is normal. If the difference Δr is equal to or greater than the shape determination threshold, the shape determination unit 94a determines that the outer shape of the wafer W is abnormal depending on the result of the retry operation.

[0045] The speed determination unit 94b determines whether the target rotation speed of the mounting table 141 set in the rotation control unit 91 is the initial speed (first speed) or the minimum speed (second speed). The minimum speed is a speed at which slip does not occur in the wafer W. Therefore, when the target speed is the minimum speed and the difference Δr is equal to or greater than the shape determination threshold, no slip occurs in the wafer W, and the speed determination unit 94b determines that there is an abnormality in the outer shape of the wafer W. In this case, the control device 80 notifies the user of the abnormality in the outer shape of the wafer W via the user interface 86. The control device 80 may also stop the operation of the alignment device 14, or may have the atmospheric transfer device 13 remove the wafer W for which an abnormality has been detected from the alignment device 14 and return it to the load port 11.

[0046] When the target speed determined by the speed determination unit 94b is the initial speed, the speed setting unit 94c resets the rotation speed of the mounting table 141 to perform a retry operation. For example, the speed setting unit 94c reads out the minimum speed (including the minimum acceleration) pre-stored in the data storage area 93 and outputs this information to the rotation control unit 91. As a result, the rotation control unit 91 sets a new target speed (minimum speed) and rotates the mounting table 141 and the wafer W at this target speed.

[0047] FIG. 7 is a diagram showing the setting of the rotation speeds of the mounting table 141 and the wafer W. (A) illustrates the speed change according to the first embodiment, and (B) illustrates the speed change according to the second embodiment. As shown in the left diagram of FIG. 7(A), the rotation speeds of the mounting table 141 and the wafer W are set to a high rotation speed and acceleration at the initial speed. And when an abnormality in the outer shape position of the wafer W is determined at this initial speed, since there is a possibility that the wafer W slips, the control device 80 switches to a second speed (minimum speed and minimum acceleration) slower than the initial speed and rotates the mounting table 141 and the wafer W (see the right diagram of FIG. 7(A)). Note that the control device 80 lowers both the constant speed (target speed) and the acceleration (including deceleration) as the second speed slower than the initial speed. Alternatively, the control device 80 may lower only the constant speed without changing the acceleration, or conversely, may lower only the acceleration without changing the constant speed.

[0048] The minimum speed and the minimum acceleration are set to appropriate values according to the mechanical characteristics of each holding member 145 and the rotation mechanism portion 143. For example, the minimum speed is preferably 1 / 3 or less of the initial speed, and more preferably set in the range of 1 / 5 to 1 / 20 of the initial speed. If the minimum speed is greater than 1 / 3 of the initial speed, the centrifugal force applied to the wafer W is large and the wafer W may slip again. On the other hand, if the minimum speed is less than 1 / 20 of the initial speed, the entire operation of the alignment device 14 may be slowed down, which may interfere with the processing of the substrate processing system 1 or reduce productivity.

[0049] When the control device 80 determines that the deviation amount between the rotation start point Rs and the rotation end point Re is outside the allowable range at the first speed in the left diagram of FIG. 7(A), it detects the outer shape position of the wafer W when rotating at the minimum speed, compares the positional deviation between the rotation start point Rs and the rotation end point Re based on the outer shape data, and executes a retry operation to determine whether the deviation amount between the rotation start point Rs and the rotation end point Re is within the allowable range. Thereby, the control device 80 can accurately determine the abnormality of the outer shape of the wafer W excluding slip.

[0050] Furthermore, the eccentricity determination unit 94d of the determination processing unit 94 calculates the amount of eccentricity, which is the positional deviation of the center of the wafer W from the center of rotation of the mounting table 141, and the eccentricity direction based on the outer shape data, and compares the calculated amount of eccentricity with an eccentricity threshold to determine whether the wafer W is normal or abnormal. The eccentricity determination unit 94d determines that the wafer W is normal when the amount of eccentricity of the wafer W is less than the eccentricity threshold, and determines that the wafer W is abnormal when the amount of eccentricity of the wafer W is equal to or greater than the eccentricity threshold. Then, the control device 80 notifies the user of the abnormality of the wafer W via the user interface 86 when the amount of eccentricity of the wafer W is equal to or greater than the eccentricity threshold.

[0051] Based on the calculated eccentricity amount and eccentricity direction of the wafer W, the correction amount calculation unit 95 calculates a correction amount for correcting the movement of the atmospheric transfer device 13 when the atmospheric transfer device 13 receives the wafer W from the mounting table 141. This enables the substrate processing system 1 to hold the wafer W by the atmospheric transfer device 13 in a state where the wafer W is aligned with high precision.

[0052] The substrate processing system 1 according to this embodiment is basically configured as described above, and its operation will be described below.

[0053] In substrate processing of a wafer W, the control device 80 of the substrate processing system 1 first controls the atmospheric transfer device 13 to remove the wafer W from the FOUP placed on the load port 11. The control device 80 then causes the atmospheric transfer device 13 to transfer the wafer W to the alignment device 14 through the clean space of the loader 12, and delivers the wafer W to the mounting table 141. As described above, the pair of forks 13a of the atmospheric transfer device 13 are formed larger in diameter than the mounting table 141, and are configured not to interfere with the mounting table 141. The atmospheric transfer device 13 can place the wafer W on the mounting table 141 by lowering the pair of forks 13a holding the wafer W from above the mounting table 141.

[0054] 8 is a flowchart showing a process flow of the substrate shape monitoring method according to the first embodiment. After the wafer W is placed on the mounting table 141, the control device 80 performs the substrate shape monitoring method in accordance with the process flow shown in FIG.

[0055] The rotation control unit 91 of the control device 80 sets a target speed for rotation of the mounting table 141, and controls the rotation mechanism unit 143 to rotate the mounting table 141 and the wafer W around the vertical axis (step S1). When rotating the wafer W for the first time after the wafer W is placed on the mounting table 141, the rotation control unit 91 sets the target speed to an initial speed (including initial acceleration) pre-stored in the data storage area 93. Then, while the mounting table 141 is rotating, the speed acquisition unit 90 acquires the actual speed detected by the encoder 144, and the rotation control unit 91 controls the rotation speed of the motor 143a so that the acquired actual speed becomes the target speed.

[0056] Furthermore, while the wafer W is rotating, the outer shape data acquisition unit 92 detects the outer shape position of the wafer W using the sensor 146, and continuously stores outer shape data in the data storage area 93, which associates the position of the wafer W in the rotational direction with the transmitted outer shape position of the wafer W (step S2). Hereinafter, the outer shape data of the wafer W rotated at the initial speed will be referred to as the first outer shape data, and the outer shape data of the wafer W rotated at the minimum speed will be referred to as the second outer shape data. As described above, the position of the wafer W in the rotational direction can be calculated based on the rotational speed acquired by the speed acquisition unit 90 and the sampling period of the sensor 146. Furthermore, acquisition of the outer shape data continues until the wafer W has made one rotation. After acquiring the outer shape data, the control device 80 temporarily stops the rotation of the wafer W.

[0057] Then, the shape determination unit 94a of the determination processing unit 94 reads out the first outer shape data stored in the data storage area 93 and determines whether the outer shape position of the wafer W is normal (step S3). At this time, the shape determination unit 94a compares the rotation start point Rs and the rotation end point Re of the first outer shape data and determines whether the rotation start point Rs and the rotation end point Re deviate by a predetermined amount or more (the difference Δr is equal to or greater than the shape determination threshold). If the outer shape position of the wafer W is normal (step S3: YES), the process proceeds to step S4. If the outer shape position of the wafer W is abnormal (step S3: NO), the process proceeds to step S8.

[0058] In step S4, the eccentricity determination unit 94d of the determination processing unit 94 calculates the eccentricity amount and eccentricity direction of the wafer W, and determines whether the eccentricity amount of the wafer W is normal. If the eccentricity amount of the wafer W is normal (step S4: YES), the process proceeds to step S5, and if the eccentricity amount of the wafer W is abnormal (step S6).

[0059] In step S5, the correction amount calculation unit 95 calculates a correction amount for correcting the movement of the atmospheric transfer device 13 based on the amount and direction of eccentricity of the wafer W.

[0060] On the other hand, in step S6, the determination processing unit 94 determines that there is an abnormality in the outer shape of the wafer W, and notifies the user of the abnormality (error) of the wafer W via the user interface 86. This allows the user of the substrate processing system 1 to recognize the abnormality of the wafer W at an early stage.

[0061] Then, the control device 80 resets the setting state of the rotation speed of the mounting table 141 set by the rotation control unit 91 (step S7), thereby ending the current substrate shape monitoring method. In the substrate shape monitoring method, if there is no abnormality in the outer shape of the wafer W, the notch n has been recognized, and the amount and direction of eccentricity of the wafer W have been calculated, the substrate processing system 1 aligns the wafer W with the atmospheric transfer device 13 based on this information. At this time, the control device 80 rotates the mounting table 141 and the wafer W based on the position of the notch n to position the notch n at a predetermined circumferential position. Furthermore, the control device 80 controls the atmospheric transfer device 13 based on the correction amount and the eccentricity direction to move the atmospheric transfer device 13 to a position where the center of the wafer W mounted on the mounting table 141 and the center of the pair of forks 13a coincide. Then, the atmospheric transfer device 13 raises the pair of forks 13a, thereby being able to hold the wafer W with the wafer W accurately aligned.

[0062] Furthermore, when the controller 80 determines in step S3 that there is an abnormality in the outer peripheral position of the wafer W, the speed determination unit 94b determines whether the target speed of the wafer W is the minimum speed (step S8). Here, when the wafer W is rotated for the first time after being placed on the mounting table 141, the target speed is set to the initial speed. Therefore, the speed determination unit 94b determines that the rotation speed of the wafer W is not the minimum speed (step S8: NO), and the process proceeds to step S9.

[0063] In step S9, the speed setting unit 94c reads the minimum speed stored in the data storage area 93 and outputs it to the rotation control unit 91, thereby setting the target speed of the rotation control unit 91 to the minimum speed (including the minimum acceleration). After step S9, the control device 80 returns to step S1 and performs a retry operation of repeating steps S1 and S2. In this retry operation, the rotation control unit 91 rotates the wafer W at the set minimum speed to prevent the wafer W from slipping relative to the mounting table 141. As a result, in step S2, second outer shape data of the wafer W, which excludes factors that may cause slip, is stored in the data storage area 93. In step S3, the shape determination unit 94a can determine whether the outer shape of the wafer W is normal based on the second outer shape data. Therefore, if the outer shape of the wafer W is normal in step S3, the wafer W can be properly aligned by performing the processes from step S4 onward.

[0064] On the other hand, if the rotation start point Rs and the rotation end point Re also deviate by more than the predetermined amount in the second contour data in step S3, the process proceeds to step S8, where the speed determination unit 94b again determines whether the rotation speed of the wafer W is the minimum speed. If the rotation speed of the wafer W is the minimum speed (step S8: YES), it can be determined that the contour of the wafer W is abnormal, excluding the cause of the wafer W slip. Therefore, the determination processing unit 94 proceeds to step S6, and notifies the user of the wafer W of an abnormality (error) via the user interface 86. This allows the user of the substrate processing system 1 to reliably recognize the abnormality of the wafer W.

[0065] As described above, in the substrate shape monitoring method according to the first embodiment, when the wafer W is rotated at the initial speed and it is determined that there is an abnormality in the outer shape of the wafer W, the rotation speed of the wafer W is reset to the minimum speed and the outer shape of the wafer W is determined again. This makes it possible to eliminate factors that may cause the wafer W to slip relative to the mounting table 141 and accurately determine the outer shape of the wafer W. As a result, the substrate processing system 1 can improve the yield of wafers W without significantly reducing the efficiency of substrate processing.

[0066] Second Embodiment The substrate processing system 1 and the substrate shape monitoring method according to the present disclosure are not limited to the above-described embodiment, and various embodiments are possible. Next, a substrate processing system 1A and a substrate shape monitoring method according to a second embodiment will be described.

[0067] FIG. 9 is a block diagram showing functional blocks of a control device 80A of a substrate processing system 1A according to the second embodiment. As shown in FIG. 9, the substrate processing system 1A according to the second embodiment differs from the control device 80 according to the second embodiment in the processing contents of the control device 80A. That is, in the second embodiment, when a retry operation determines that the deviation amount of the outer position of the substrate is equal to or greater than a threshold, the second speed is set to multiple speeds (intermediate speed, minimum speed) so that the rotation speed is gradually reduced. The control device 80A then repeats the retry operation of reducing the second speed until it determines that the deviation amount of the outer position of the wafer W is less than the shape determination threshold or until it reaches a preset minimum speed. Alternatively, the control device 80A may have multiple accelerations (intermediate acceleration, minimum acceleration), and when a retry operation determines that the deviation amount of the outer position of the substrate is equal to or greater than a threshold, the control device 80A may repeat the retry operation so that the acceleration (including deceleration) during rotation is gradually reduced. That is, the control device 80A may be configured to gradually reduce either one or both of the multiple rotation speeds and the multiple accelerations. Alternatively, the control device 80A may alternately reduce the rotation speed and the acceleration in stages.

[0068] Specifically, the control device 80A includes a speed acquisition unit 90, a rotation control unit 91, an outer shape data acquisition unit 92, a data storage area 93, a judgment processing unit 94, a correction amount calculation unit 95, as well as a user setting unit 96 and a next speed setting unit 98. The control device 80A allows the user to set the rotation speed of the wafer W in the alignment device 14.

[0069] The user setting unit 96 allows the user to set an intermediate speed and / or intermediate acceleration, which are the rotation speed of the wafer W, by, for example, displaying a speed setting screen (not shown) via the user interface 86. The intermediate speed is a speed between the initial speed and the minimum speed. For example, the speed setting screen may be configured to display a range of settable intermediate speeds and allow the user to input or select. Alternatively, the speed setting screen may not allow input of rotation speeds higher than the initial speed or lower than the minimum speed. If slippage occurs in the wafer W at the initial speed, the control device 80A can rotate the wafer W at the set intermediate speed, thereby suppressing slippage in the wafer W and successfully acquiring outer shape data of the wafer W.

[0070] By allowing the user to set the intermediate speed in this manner, the control device 80A can determine an abnormality in the outer shape position of the wafer W while gradually decreasing the rotation speed of the wafer W in the order of the initial speed, the intermediate speed, and the minimum speed, as shown in Fig. 7(B). Note that the control device 80A is not limited to a configuration in which only one intermediate speed is set, and may be configured to be able to set multiple intermediate speeds.

[0071] Furthermore, the user setting unit 96 is not limited to setting a constant speed portion (target speed) when setting the intermediate speed, but may also be configured to set an acceleration period or deceleration period (i.e., acceleration) during the rotation of the wafer W. As described above, slippage of the wafer W may occur due to a large acceleration or deceleration during rotation of the wafer W. Therefore, by making the acceleration period and deceleration period variable, the control device 80A can reduce factors that cause slippage due to acceleration or deceleration. The user setting unit 96 may, for example, display a trapezoidal speed pattern (see the center diagram in FIG. 7(B)) on the speed setting screen, allowing the user to adjust or select the acceleration period and deceleration period through operation.

[0072] Alternatively, the control device 80A may include an automatic setting unit 97 that automatically sets the intermediate speed and / or acceleration, as indicated by the dotted lines in FIG. 9 . For example, the automatic setting unit 97 may set the intermediate speed and / or the intermediate acceleration based on the contour data obtained when the wafer W is rotated at the initial speed. As an example, the automatic setting unit 97 may set the intermediate speed close to the minimum speed when the difference Δr between the rotation start point Rs and the rotation end point Re is large, and may set the intermediate speed close to the initial speed when the difference Δr is small. Also, for example, the automatic setting unit 97 may set the intermediate speed based on the eccentricity of the wafer W when the wafer W is rotated at the initial speed.

[0073] The automatic setting unit 97 may estimate the timing of slippage using past contour data and adjust the intermediate speed and / or intermediate acceleration according to the estimated timing of slippage. For example, if it is determined based on the contour data that slippage occurs at the initial stage of rotation of the wafer W, the automatic setting unit 97 may set an intermediate speed with a longer acceleration period and a lower acceleration. The timing of slippage can be estimated by extracting a point where the waveform (sine wave, cosine wave) of the contour data suddenly changes from the normal waveform (the dotted waveform in FIG. 5(B)). Alternatively, the automatic setting unit 97 may learn using multiple contour data stored in the data storage area 93, and may estimate the timing of slippage by calculating the correlation between the learned data and the current contour data.

[0074] The next speed setting unit 98 is a functional unit that determines whether the current rotation speed of the wafer W should be applied to the speed at which the wafer W is first rotated after the next wafer W is placed on the mounting table 141, and appropriately sets the rotation speed of the next wafer W. For example, if the next speed setting unit 98 determines that the outer shape of the wafer W is normal when the wafer W is rotated at an intermediate speed, it sets the rotation speed of the next wafer W to the intermediate speed. This makes it possible to rotate the wafer W and acquire outer shape data of the wafer W in a state where the possibility of the next wafer W slipping is reduced.

[0075] At this time, the next speed setting unit 98 may adopt the rotation speed of the current wafer W for wafers W taken out from the same FOUP (load port 11), and may perform processing to return the speed to the initial speed if the FOUP is changed.

[0076] The substrate processing system 1A according to the second embodiment is basically configured as described above, and its operation will be described below with reference to Figures 10 and 11. Figure 10 is a flowchart showing the processing flow for substrate shape monitoring broadcasting according to the second embodiment. Figure 11 is a flowchart showing the speed determination processing subroutine of Figure 10.

[0077] The processing flow from steps S11 to S16 in the substrate shape monitoring method according to the second embodiment is the same as steps S1 to S6 in the substrate shape monitoring method according to the first embodiment (see FIG. 8). Therefore, a description of the specific processing will be omitted. On the other hand, if it is determined in step S13 that there is an abnormality in the outer shape position of the wafer W (step S13: NO), the control device 80A proceeds to step S17 and executes a speed determination processing subroutine.

[0078] 11, in the speed determination process subroutine, the speed determination unit 94b first determines whether the rotation speed of the wafer W is the initial speed (including the initial acceleration) (step S171). If the rotation speed of the wafer W is the initial speed (step S171: YES), the process proceeds to step S172, and if the rotation speed of the wafer W is other than the initial speed (step S171: NO), the process proceeds to step S176.

[0079] In step S172, the speed determination unit 94b determines whether or not there is an intermediate speed and / or intermediate acceleration that has been set by the user setting unit 96 or the automatic setting unit 97. If there is an intermediate speed and / or intermediate acceleration that has been set (step S172: YES), the process proceeds to step S173, and if there is no intermediate speed that has been set, the process proceeds to step S175.

[0080] In step S173, the speed setting unit 94c sets the intermediate speed and / or intermediate acceleration to the set intermediate speed and / or intermediate acceleration. The intermediate speed is a target speed (constant speed) between the initial speed and the minimum speed, and the intermediate acceleration is a speed in which an acceleration period and a deceleration period are appropriately set between the initial acceleration and the minimum acceleration. The following describes a case in which an intermediate speed including an intermediate acceleration is set. After setting the intermediate speed, the control device 80A performs processing returning to step S11 (step S174) to end the speed determination processing subroutine. As a result, when the control device 80A rotates the wafer W again in the retry operation, it rotates the wafer W at the intermediate speed. Then, in step S12, the outer shape data (second outer shape data) of the wafer W rotating at the intermediate speed is stored.

[0081] On the other hand, if it is determined in step S172 that there is no intermediate speed set, the speed setting unit 94c sets the minimum speed and / or minimum acceleration stored in the data storage area 93 (step S175). The following describes the case where the minimum speed including the minimum acceleration is set. After setting the minimum speed, the control device 80A returns to step S11 (step S174) to end the speed determination process subroutine. As a result, when the control device 80A rotates the wafer W again in the retry operation, it rotates the wafer W at the minimum speed. Then, in step S12, the outer shape data (third outer shape data) of the wafer W rotating at the minimum speed is stored.

[0082] Furthermore, if the rotation speed of the wafer W is not the initial speed in step S171, the speed determination unit 94b next determines whether the rotation speed of the wafer W is the intermediate speed (step S176). If the rotation speed of the wafer W is the intermediate speed (step S176: YES), it means that slip has occurred in the wafer W even if the rotation speed of the wafer W was set to the intermediate speed. Therefore, the speed setting unit 94c proceeds to step S175 and changes the rotation speed of the wafer W to the minimum speed. From step S175 onwards, the same process flow as above is performed. This allows the control device 80A to obtain outer shape data (third outer shape data) of the wafer W rotating at the minimum speed, and to determine whether the outer shape of the wafer W is normal or abnormal while eliminating the cause of slip.

[0083] On the other hand, if the rotation speed of the wafer W is not the intermediate speed (step S176: NO), it is determined that the rotation speed was the minimum speed at which slip does not occur on the wafer W. Therefore, the determination processing unit 94 notifies the user via the user interface 86 that there is an abnormality in the outer peripheral position of the wafer W (step S177). This allows the user of the substrate processing system 1 to stably recognize the abnormality of the wafer W. After notifying the error, the control device 80A may stop the operation of the substrate processing system 1 or the alignment device 14 alone, or may perform an operation to remove the erroneous wafer W using the atmospheric transfer device 13. In this way, by executing the speed determination processing subroutine, the control device 80A can smoothly set multiple speeds (initial speed, intermediate speed, minimum speed, initial acceleration, intermediate acceleration, minimum acceleration) and accurately recognize whether the outer peripheral position of the wafer W is normal or abnormal.

[0084] 10, when the determination of the amount of eccentricity of the wafer W indicates that the wafer W is normal and the correction amount has been calculated, the next speed setting unit 98 determines whether or not a retry operation was performed in the current alignment of the wafer W (step S18). If a retry operation was not performed (step S18: YES), the next speed setting unit 98 determines to use the initial speed, which was the current rotation speed of the wafer W, as is, and ends the current processing flow.

[0085] On the other hand, if the retry operation has been performed (step S18: NO), it is determined whether the rotation speed of the wafer W during the retry operation should be used in the next alignment of the wafer W (step S19). For example, when the wafer W is taken out from the same FOUP (step S118: YES), that is, when the wafer W is from the same lot, the next speed setting unit 98 sets the rotation speed to the rotation speed during the retry operation. This allows the substrate processing system 1 to rotate the wafer W at the rotation speed during the retry operation after the next wafer W is placed on the placement table 141, thereby preventing the wafer W from slipping.

[0086] Conversely, in a situation where the next wafer W is from a different lot, it is determined that the rotation speed of the wafer W should not be set to the rotation speed during the retry operation (step S18: NO). As a result, the next speed setting unit 98 resets the rotation speed of the wafer W (step S20). As a result, the substrate processing system 1A can initially rotate the wafer W at the initial speed when rotating the next wafer W.

[0087] As described above, the substrate processing system 1A and the substrate shape monitoring method according to the second embodiment, like the first embodiment, can avoid erroneous detection due to slippage of the wafer W and accurately monitor the outer shape position of the wafer W. In particular, by setting an intermediate speed and / or intermediate acceleration, the substrate processing system 1A can perform a retry operation without significantly reducing the speed during alignment, thereby suppressing a decrease in processing efficiency of the entire system.

[0088] The substrate processing system 1 is not limited to installing the alignment device 14 in the front module FM, and the alignment of the wafer W may be performed at another location in the substrate processing system 1. For example, as shown by the dotted line in FIG. 1 , the substrate processing system 1 may install the alignment device 14A inside the transfer module TM. In the transfer module TM, the wafer W tends to slip easily when the transfer container 31 is depressurized to a vacuum atmosphere. Therefore, the alignment device 14A can prevent the wafer W from slipping by appropriately changing the rotation speed during alignment of the wafer W.

[0089] Alternatively, the substrate processing system 1 may provide the stage 24 of the load lock module LLM with a function for aligning the wafer W, and the load lock module LLM may detect the outer position of the wafer W. In this case, too, by appropriately changing the rotation speed during alignment of the wafer W, slip of the wafer W can be suppressed.

[0090] Furthermore, if the wafer W does not slip during one or more initial rotations of the wafer W after being placed on the mounting table 141, the control device 80 may increase the rotation speed and / or acceleration of the wafer W to be detected next. This allows the substrate processing system 1 and the substrate shape monitoring method to further improve processing efficiency. For example, after performing a retry operation at the minimum speed, the control device 80 may gradually increase the rotation speed without continuously using the minimum speed for subsequent detection of the outer peripheral position of the wafer W, thereby suppressing slip and promoting processing efficiency. Furthermore, for example, if the wafer W does not slip at the current initial speed, the control device 80 may, of course, change the next initial speed and / or acceleration to a rotation speed higher than the current initial speed. If the wafer W slips due to the increased speed, the control device 80 may reduce the rotation speed to the previous level when detecting the outer peripheral position of the next wafer W.

[0091] In short, the control device 80 is preferably configured to search for optimal values ​​of the rotational speed and / or acceleration when the wafer W is first rotated after being placed on the mounting table 141, which allow the wafer W to be rotated quickly while suppressing the occurrence of slips. For example, the optimal values ​​of the rotational speed and / or acceleration can be adjusted to appropriate values ​​by decreasing the rotational speed and / or acceleration by a predetermined speed unit when a slip occurs, and increasing the rotational speed and / or acceleration by a predetermined speed unit when a slip occurs. Alternatively, the control device 80 may calculate the optimal values ​​of the rotational speed and / or acceleration by learning the tendency of the rotational speed and / or acceleration at which slips occur in the wafer W based on multiple rotational speeds and / or accelerations at which slips occurred in the past.

[0092] Furthermore, the control device 80 may store information on the type of wafer W detected in the past, and information on the rotational speed and / or acceleration at the time of detection, in association with each other. When the outer position of the wafer W is first detected, the control device 80 may search for the type of wafer W and, if the same wafer W has been detected in the past, set the rotational speed and / or acceleration to a value at which no slip occurred. This allows the control device 80 to quickly set an appropriate rotational speed and / or acceleration for the same type of wafer W, further improving processing efficiency. For example, the control device 80 can easily obtain information on the type of wafer W by identifying an identification number for each lot (FOUP) and store it in memory. Alternatively, the identification information may be embedded in the wafer W itself, and the control device 80 may read the identification information when the wafer W is transported.

[0093] In addition, if the wafer W slips multiple times at a rotation speed at which the wafer W has not slipped in the past (e.g., the lowest speed), the control device 80 may estimate deterioration of the holding member 145 and prompt the user to perform maintenance.

[0094] The technical ideas and effects of the present disclosure explained in the above embodiments will be described below.

[0095] A first aspect of the present disclosure is a substrate processing system 1, 1A for processing a substrate (wafer W), which includes a mounting table 141 for mounting the substrate, a rotation mechanism 143 for rotating the mounting table 141, a sensor 146 for detecting the outline of the substrate while the substrate is rotating, and a control device 80, 80A, wherein the control device 80, 80A controls the following steps: (a) when rotating the substrate for the first time, rotating the mounting table at a first speed and a first acceleration; (b) when rotating the mounting table once from the rotation start point to the rotation end point, referring to information on the outline position of the substrate detected by the sensor, determining whether the deviation amount of the outline position of the substrate between the rotation start point Rs and the rotation end point Re is greater than or equal to a threshold value (shape determination threshold); and (c) when it is determined that the deviation amount of the outline position of the substrate is greater than or equal to the threshold value, rotating the mounting table 141 at a second speed lower than the first speed and / or a second acceleration lower than the first acceleration, and performing a retry operation of the determination of (b).

[0096] As described above, when a substrate (wafer W) is rotated at a first speed and a first acceleration and the substrate slips, causing the rotation start point Rs and the rotation end point Re to deviate by more than a threshold value (shape determination threshold), the substrate processing system 1, 1A can rotate the substrate at a second speed and / or a second acceleration to detect its outer shape position. Therefore, the outer shape position is detected by rotating the substrate while suppressing substrate slippage, thereby suppressing erroneous detection of the outer shape position of the substrate. As a result, the substrate processing system 1, 1A can suppress a decrease in yield due to errors in the outer shape position of the substrate.

[0097] Furthermore, the second speed and / or the second acceleration are set to be gradually lower in step (c) when the retry operation determines that the deviation amount of the outer position of the substrate (wafer W) is equal to or greater than a threshold (shape determination threshold), and the control devices 80, 80A repeat the retry operations of steps (c) and (b) until it is determined that the deviation amount of the outer position of the substrate is less than the threshold, or until the second speed reaches a preset minimum speed and the second acceleration reaches a preset minimum acceleration. This enables the substrate processing system 1 to detect the outer position of the substrate by lowering the rotation speed to a speed at which the substrate does not slip, thereby improving detection accuracy.

[0098] Furthermore, when the control device 80, 80A determines that the deviation amount of the outer shape position of the substrate (wafer W) is equal to or greater than a threshold value (shape determination threshold value) as a result of repeating the retry operation of the steps (c) and (b) until the second speed becomes the minimum speed and the second acceleration becomes the preset minimum acceleration, it determines that there is an abnormality in the outer shape of the substrate and notifies the user of error information. This allows the substrate processing system 1, 1A to smoothly make the user aware of an abnormality in the outer shape of the substrate when the rotation start point Rs and the rotation end point Re are misaligned even after excluding causes of substrate slip.

[0099] Furthermore, when the controller 80, 80A determines that the amount of deviation of the substrate (wafer W) between the rotation start point Rs and the rotation end point Re is less than a threshold value (shape determination threshold value) as a result of repeating the retry operations of the steps (c) and (b), the controller 80, 80A determines that a slip has occurred during the rotation of the substrate. This allows the substrate processing system 1, 1A to recognize the occurrence of a slip of the substrate, and for example, by accumulating slip data, it becomes possible to adjust the rotation speed of the substrate (first speed, etc.) to an optimal value that does not cause a slip.

[0100] The second speed value and / or the second acceleration value, which are set to be gradually lower, can be set by the user, thereby allowing the substrate processing system 1A to set the rotation speed of the substrate (wafer W) to an appropriate speed as desired by the user.

[0101] Furthermore, when the control device 80, 80A determines in steps (d) and (b) that the deviation amount of the outer shape position of the substrate (wafer W) is less than a threshold value (shape determination threshold), it performs a step of calculating the eccentricity amount of the substrate. This enables the substrate processing system 1, 1A to accurately set the correction amount for the movement of the atmospheric transfer device 13 relative to the substrate based on the eccentricity amount of the substrate, thereby enabling accurate alignment of the atmospheric transfer device 13 and the substrate.

[0102] Furthermore, the control device 80, 80A controls the detection of the outer position of the substrate (wafer W) to be repeatedly performed for multiple substrates, and in step (a), when detecting the outer position of each of the multiple substrates, sets a predetermined initial speed to the first speed and a predetermined initial acceleration to the first acceleration, and initially rotates the mounting table 141 at the first speed and the first acceleration. By rotating each of the multiple substrates at the first speed in this manner, the substrate processing system 1, 1A can maintain processing efficiency and slow down the rotation speed only when an abnormality is detected in the outer position of the substrate.

[0103] Furthermore, the control device 80 controls the detection of the outer position of the substrate (wafer W) to be repeatedly performed for multiple substrates, and if it determines that the deviation of the outer position of the substrate is less than the threshold value (shape determination threshold) as a result of performing a retry operation by setting the second speed and / or the second acceleration for any of the multiple substrates prior to the previous one, it sets the first speed to the second speed or a third speed higher than the second speed, and / or sets the first acceleration to the second acceleration or a third acceleration higher than the second acceleration, when detecting the outer position of the substrate from this time onwards, and rotates the mounting table 141 at the first speed in step (a). As a result, the substrate processing system 1, 1A can prevent slippage of the substrate by rotating the substrate at a slow rotation speed from the beginning when detecting the outer position of the next substrate.

[0104] The control device 80 also stores in a storage unit (memory 82) the type of substrate (wafer W) and the rotation speed at which it is determined that the amount of substrate misalignment is less than a threshold (shape determination threshold). When the type of substrate for which the current outer shape position is to be detected is acquired and a previous substrate of the same type is found, the control device 80 sets the rotation speed of the previous substrate of the same type when the substrate is first rotated after being placed on the mounting table 141. This allows the rotation speed of the current substrate to be easily adjusted to the rotation speed of the previous substrate when the substrate type is the same. Substrate types include product wafers, dummy wafers, etc. The control device 80 can identify the substrate when it is loaded by the identification information provided on the substrate itself.

[0105] Furthermore, a second aspect of the present disclosure is an alignment device 14 that aligns a substrate (wafer W) based on information about the outer shape position of the substrate, and includes a mounting table 141 on which the substrate is placed, a rotation mechanism 143 that rotates the mounting table 141, and a sensor 146 that detects the outer shape of the substrate while the substrate is rotating. The rotation mechanism 143 rotates the mounting table 141 once from a rotation start point Rs to a rotation end point Re at a first speed and a first acceleration, while the sensor 146 detects the outer shape position of the substrate. If the information about the outer shape position of the substrate detected by the sensor 146 indicates that the rotation start point Rs and the rotation end point Re deviate by more than a threshold value, the rotation mechanism 143 rotates the mounting table once from the rotation start point Rs to the rotation end point Re at a second speed lower than the first speed and / or a second acceleration lower than the first acceleration, while the sensor 146 performs a retry operation to detect the outer shape position of the substrate.

[0106] Furthermore, a substrate shape monitoring method according to a third aspect of the present disclosure includes the steps of: (a) rotating a mounting table 141 carrying a substrate (wafer W) at a first speed and a first acceleration when initially detecting the outer shape position of the substrate; (b) determining whether the deviation amount of the outer shape position of the substrate between the rotation start point Rs and the rotation end point Re is equal to or greater than a threshold value (shape determination threshold value) by referring to information on the outer shape position of the substrate detected by a sensor 146 when the mounting table 141 is rotated once from the rotation start point Rs to the rotation end point Re; and (c) if it is determined that the deviation amount of the outer shape position of the substrate is equal to or greater than the threshold value, rotating the mounting table 141 at a second speed lower than the first speed and / or a second acceleration lower than the first acceleration, and performing a retry operation of the determination in (b).

[0107] In the second and third aspects described above, it is also possible to suppress erroneous detection of the outer shape of the substrate when the outer shape position is detected by rotating the substrate (wafer W).

[0108] The substrate processing systems 1, 1A, alignment devices 14, and substrate shape monitoring methods according to the presently disclosed embodiments are illustrative in all respects and are not limiting. The embodiments may be modified and improved in various ways without departing from the spirit and scope of the appended claims. The features described in the above embodiments may be configured differently and may be combined within the scope of the appended claims. [Explanation of symbols]

[0109] 1. 1A Substrate Processing System 80, 80A control device 141 Mounting table 143 Rotation mechanism 146 Sensors Re rotation end point Rs Starting point of rotation W wafer

Claims

1. A substrate processing system for processing a substrate, a mounting table on which the substrate is placed; a rotation mechanism that rotates the mounting table; a sensor for detecting an outer position of the substrate while the substrate is rotating; a control device; The control device (a) rotating the mounting table at a first speed and a first acceleration when initially rotating the substrate; (b) determining whether or not the deviation of the outer position of the substrate between the rotation start point and the rotation end point is equal to or greater than a threshold value, by referring to information on the outer position of the substrate detected by the sensor when the mounting table is rotated once from the rotation start point to the rotation end point; (c) when it is determined that the deviation amount of the outer shape position of the substrate is equal to or greater than a threshold value, rotating the mounting table at a second speed lower than the first speed and / or at a second acceleration lower than the first acceleration, and performing a retry operation of the determination in (b). Substrate processing system.

2. the second speed and / or the second acceleration are set to be gradually lower in the step (c) when it is determined that the deviation amount of the outer position of the substrate is equal to or greater than a threshold value as a result of the retry operation, the control device repeats the retry operations of the steps (c) and (b) until it is determined that the deviation amount of the outer shape position of the substrate is less than a threshold value, or until the second speed becomes a preset minimum speed and the second acceleration becomes a preset minimum acceleration. The substrate processing system of claim 1 .

3. the control device repeats the retry operations of the steps (c) and (b) until the second speed becomes the minimum speed and the second acceleration becomes a preset minimum acceleration, and when it determines that the deviation amount of the outer shape position of the substrate is equal to or greater than a threshold, it determines that there is an abnormality in the outer shape of the substrate and notifies error information. The substrate processing system of claim 2 .

4. When the control device determines that the deviation amount of the outer shape position of the substrate is less than a threshold value as a result of repeating the retry operations of the step (c) and the step (b), the control device determines that the substrate is not slipping during rotation. The substrate processing system of claim 2 .

5. The value of the second speed and / or the value of the second acceleration, which are set to be gradually decreased, can be set by a user. The substrate processing system of claim 2 .

6. The control device (d) performing a step of calculating an amount of eccentricity of the substrate when it is determined in the step (b) that the amount of deviation of the outer shape position of the substrate is less than a threshold value; The substrate processing system according to claim 1 .

7. The control device controlling the detection of the outer shape position of the substrate so as to be repeatedly performed for a plurality of the substrates; In the step (a), when detecting the outer position of each of the plurality of substrates, a predetermined initial velocity is set as the first velocity and a predetermined initial acceleration is set as the first acceleration, and the mounting table is initially rotated at the first velocity and the first acceleration. The substrate processing system of claim 1 .

8. The control device controlling the detection of the outer shape position of the substrate so as to be repeatedly performed for a plurality of the substrates; and when the retry operation is performed with the second speed and / or the second acceleration set for any of the substrates prior to the previous retry and it is determined that the deviation amount of the outer peripheral position of the substrate is less than the threshold value, when detecting the outer peripheral positions of the substrates from this time onwards, the first speed is set to the second speed or a third speed higher than the second speed, and / or the first acceleration is set to the second acceleration or a third acceleration higher than the second acceleration, and in step (a), the mounting table is rotated at the first speed. The substrate processing system of claim 1 .

9. The control device the type of the substrate and the rotation speed at which it was determined that the amount of deviation of the substrate was less than a threshold are stored in a storage unit, and when the type of the substrate for which the outer position is to be detected this time is obtained and there is a previous substrate of the same type, the rotation speed of the previous substrate of the same type is set when the substrate is rotated for the first time after being placed on the mounting table. The substrate processing system of claim 1 .

10. An alignment device that aligns a position of a substrate based on information about the outer shape position of the substrate, a mounting table on which the substrate is placed; a rotation mechanism that rotates the mounting table; a sensor for detecting an outer peripheral position of the substrate while the substrate is rotating; the rotation mechanism rotates the mounting table once at a first speed and a first acceleration from a rotation start point to a rotation end point, while the sensor detects an outer position of the substrate; when the information on the outer position of the substrate detected by the sensor indicates a deviation of a predetermined amount between the rotation start point and the rotation end point, the rotation mechanism rotates the mounting table once from the rotation start point to the rotation end point at a second speed lower than the first speed and / or a second acceleration lower than the first acceleration, while performing a retry operation in which the sensor detects the outer position of the substrate. Alignment device.

11. (a) rotating a mounting table on which a substrate is placed at a first speed and a first acceleration when detecting an outer shape position of the substrate for the first time; (b) determining whether or not the deviation of the outer position of the substrate between the rotation start point and the rotation end point is equal to or greater than a threshold value by referring to information on the outer position of the substrate detected by a sensor when the mounting table is rotated once from the rotation start point to the rotation end point; (c) when it is determined that the deviation amount of the outer shape position of the substrate is equal to or greater than a threshold, rotating the mounting table at a second speed lower than the first speed and / or at a second acceleration lower than the first acceleration, and performing a retry operation of the determination in (b), Board shape monitoring method.

Images